U.S. GOVERNMENT PRINTING OFFICE

68–499 WASHINGTON : 2011

112th Congress, 1st Session – – – – – – – – – – – – – House Document 112–43 

RECOMMENDATIONS FOR THE IMPLEMENTATION OF 

FOUR PROJECTS 

COMMUNICATION

FROM

THE ASSISTANT SECRETARY OF THE ARMY, 

CIVIL WORKS, THE DEPARTMENT OF DEFENSE

TRANSMITTING

RECOMMENDATIONS FOR THE IMPLEMENTATION OF FOUR 

PROJECTS BY THE SECRETARY OF THE ARMY 

PART 1 OF VOLUME V OF VI 

JULY 12, 2011.—Referred to the Committee on Transportation and 

Infrastructure and ordered to be printed 

LOUISIANA COASTAL AREA (LCA)

ECOSYSTEM RESTORATION STUDY

Volume V of VI

Integrated Feasibility Study and

Final Environmental Impact Statement

for the

Terrebonne Basin Barrier Shoreline Restoration

Terrebonne Parish, Louisiana

October 2010

U.S Army Corps of Engineers

New Orleans District

Coastal Protection and

Restoration Authority

(1)
LOUISIANA COASTAL AREA (LCA)

ECOSYSTEM RESTORATION STUDY

Volume V of VI

Integrated Feasibility Study and

Final Environmental Impact Statement

for the

Terrebonne Basin Barrier Shoreline Restoration

Terrebonne Parish, Louisiana

The responsible lead Federal agency for this study is the U. S. Army Corps of

Engineers- Mississippi Valley, New Orleans District (CEMVN). The non-Federal

sponsor for the study is Coastal Protection and Restoration Authority (CPRA).

This report is a combined feasibility report and environmental impact statement

complying with requirements of the U.S. Army Corps of Engineers (USACE) and

the Council of Environmental Quality (CEQ), and is intended to reduce duplication

and paperwork. An asterisk (*) in the table of contents notes paragraphs that are

required for the National Environmental Policy Act (NEPA) compliance.

October 2010

U.S Army Corps of Engineers

New Orleans District

Coastal Protection and

Restoration Authority

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Integrated Feasibility Study and Final Environmental Impact Statement

for the

Terrebonne Basin Barrier Shoreline Restoration

LEAD AGENCY: United States Army Corps of Engineers  Mississippi Valley

Division, New Orleans District

ABSTRACT: The United States Army Corps of Engineers (USACE), New Orleans

District (CEMVN), proposes to restore approximately 1,272 acres of dune,

supratidal, and intertidal habitat on the Terrebonne Basin Barrier Shoreline.

Without action, this critical geomorphic feature that isolates the Terrebonne Basin

estuaries from the Gulf of Mexico will continue to degrade, existing breaches will

widen and new breaches will form, and portions of the Study Area will disappear in

the near-term. Six alternative plans, including the No Action plan, were developed

and evaluated as the Final Array. Alternative 5 (Raccoon with Terminal Groin

(Plan E) / Whiskey (Plan C) / Trinity (Plan C) / and Timbalier (Plan E)) was selected

as the National Ecosystem Restoration (NER) Plan because it is a Best Buy plan

that fulfills the planning objectives of the Study. The alternative increases the

longevity of the geomorphologic form and ecologic function of the four islands in the

Terrebonne Basin barrier system by creating a total of 472 acres of dune habitat,

4320 acres of supratidal habitat, and 1048 acres of intertidal habitat immediately

after construction. However, the NER Plan cannot be constructed within the

maximum project cost as authorized by Water Resources Development Act (WRDA)

2007 and modified according to section 902 of WRDA 1986, as amended. Therefore,

Whiskey Plan C, a subset of the NER Plan, was selected as the recommended

component of construction. The USACE will seek additional authorization in order

to construct additional increments of the NER Plan. Immediately after construction

(Target Year 1), the recommended component of construction will add 469 acres of

habitat (dune, supratidal, and intertidal) to the existing island footprint, increasing

the size of the island to 1,272 acres. The fully funded cost of the Whiskey Plan C is

approximately $119,000,000, without renourishment. The two renourishment

cycles will cost an additional $341,000,000. However, renourishment is considered

an operation and maintenance cost that will be fully-funded by the non-Federal

sponsor and does not count toward the maximum project cost of $189,900,000 as

authorized by WRDA 2007 and modified according to section 902 of WRDA 1986.

Comments: Please send comments or questions on this Final Environmental

Impact Statement (FEIS) to the United States Army Corps of Engineers, New

Orleans District, Attention: William P. Klein, Jr., P.O. Box 60267, New Orleans,

Louisiana 70160-0267. Telephone: (504) 862-2540; FAX: (504) 862-2088. The

official closing date for receipt of comments will be 30 days from the date

on which the Notice of Availability of the FEIS appeared in the Federal

Register.

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EXECUTIVE SUMMARY

ES 1 Summary Introduction and Study Information

The United Sates Army Corps of Engineers (USACE), Mississippi Valley Division,

New Orleans District (CEMVN), proposes to restore approximately 1,272 acres of

dune, supratidal, and intertidal habitat on the Terrebonne Basin Barrier Shoreline

in lower Terrebonne and Lafourche Parishes, Louisiana. The Terrebonne Basin

Barrier Shoreline is comprised of two barrier island reaches: the Isles Dernieres and

the Timbalier Islands.

The Isles Dernieres reach includes Raccoon, Whiskey, Trinity, East, and Wine

Islands. The Timbalier Island reach includes Timbalier and East Timbalier

Islands. These barrier islands have undergone significant reductions in size due to a

number of natural processes and human actions including lack of sediment, storminduced erosion and breaching, subsidence, sea level rise and hydrologic

modifications such as navigation and oil and gas canals. These habitat losses have

had a direct adverse impact on wildlife and fisheries resources including threatened

and endangered species. Loss of the barrier island habitat also leaves the fragile

saline, brackish, and fresh marshes in the upper reaches of the Terrebonne Basin

more vulnerable to the high energy marine coastal processes which have

exacerbated wetland loss in these areas. The barrier islands also protect oil and gas

infrastructure investments including hundreds of wells and pipelines which are of

regional and national importance. Furthermore, numerical modeling has

demonstrated that the barrier islands reduce storm surges which can mitigate the

damage associated with tropical storms on human populations and infrastructure in

Terrebonne and Lafourche Parishes.

Without action, these critical geomorphic features that isolate the Terrebonne Basin

estuaries from the Gulf of Mexico will continue to degrade, existing breaches will

widen and new breaches will form, and portions of the Study Area will disappear in

the near-term. Raccoon, Whiskey, Trinity, East, and Wine Island are expected to

completely disappear by 2052 if no action is taken. By 2062, Timbalier and East

Timbalier will only have 6 acres of subaerial habitat left.

ES 2 Need for, and Objectives of Action *

Ecosystem restoration is one of the primary missions of the USACE Civil Works

program. The USACE objective in ecosystem restoration planning is to contribute to

National Ecosystem Restoration (NER) Plan. Contributions to national ecosystem

restoration (NER outputs) are increases in the net quantity and/or quality of

desired ecosystem resources. Measurement of the NER Plan is based on changes in

ecological resource quality as a function of improvement in habitat quality and/or

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quantity and expressed quantitatively in physical units or indexes. These net

changes are measured in the planning area and in the rest of the Nation.

Louisiana contains one of the largest expanses of coastal wetlands in the contiguous

United States and accounts for 90% of the total coastal marsh loss occurring in the

nation. The Terrebonne Basin Barrier Shoreline Restoration (TBBSR) Study Area

is an essential ecosystem since it includes wetland habitats, essential fish habitat,

and has high fish and wildlife values. The barrier islands protect the interior

coastal wetlands, which also have high fish and wildlife value as well as great

economic value as commercial and recreational fisheries. These ecosystems provide

habitat for migratory birds, wildlife, finfish, shellfish, and other aquatic organisms

including threatened or endangered species. Port Fourchon, located just east of the

Study Area handles approximately 18% of the nations oil supply and is the land

base for the Louisiana Offshore Oil Port (LOOP). LOOP handles approximately

15% of the nations foreign oil imports and is connected to 50% of the United States

refinery capacity. The estuaries landward of the Terrebonne Basin Barrier

Shoreline are productive oyster habitat and have traditionally supported important

fisheries. The restoration of these barrier shorelines will protect these national

assets from further degradation.

For the Louisiana Coastal Area (LCA) 2004 Study, two tiers of planning objectives

were established  hydrogeomorphic and ecosystem objectives. The

hydrogeomorphic objectives were:

 Establish dynamic salinity gradients that reflect natural cycles of

freshwater availability and marine forcing.

 Increase sediment input from sources outside estuarine basins, and

manage existing wetlands and rebuild marsh substrate.

 Maintain or establish natural landscape features and hydrologic processes

that are critical to sustainable ecosystem structure and function.

The ecosystem objectives were:

 Sustain productive and diverse fish and wildlife habitats.

 Reduce nutrient delivery to the Continental shelf by routing Mississippi

river waters through estuarine basins while minimizing potential adverse

effects.

The LCA TBBSR Study objectives are a localized and project specific delineation of

the LCA objectives. The Terrebonne Basin barrier shoreline is a unique ecosystem

that helps to maintain the integrity of the gulf shoreline and protects the interior

coast from further degradation. Aside from supporting coastal habitats, the coastal

barrier chains in Louisiana are the first line of defense for protecting wetlands,

inland bays, and mainland regions from direct effects of wind, waves, and storms.

The barrier systems serve multiple defensive purposes to:

 Reduce coastal flooding during periods of storm surge.

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 Prevent direct ocean wave attack, which would accelerate rates of erosion

and degradation of marshes and other wetlands; and

 Help maintain gradients between saline and freshwater, thereby

preserving estuarine systems.

Natural processes and human actions, such as the construction of oil field canals

and the containment of waterways, have threatened the long-term viability of the

Study Area. These processes and activities have caused significant adverse impacts

to the Terrebonne Basin barrier island shoreline, resulting in extensive barrier

island habitat loss and ecosystem degradation (USACE, 2004). Based on the

function of these barrier islands and problems identified for the Terrebonne islands

during this study, the following planning objectives were developed to assist the

development and evaluation of alternative plans.

 Provide an expanded footprint of minimized barrier island sections to

provide the geomorphic form and ecologic function of the Terrebonne

Basin barrier island, reducing volume loss within the LCA TBBSR Study

Area below the historic average (1880 through 2005)

 Restore and improve various barrier island habitats that provide essential

habitats for fish, migratory birds, and other terrestrial and aquatic

species, mimicking, as closely as possible, conditions which would occur

naturally in the area for the 50 year period of analysis.

 Increase sediment input to supplement longshore sediment transport

processes along the gulf shoreline by mechanically introducing compatible

sediment, and increasing the ability of the restored area to continue to

function and provide habitat for the 50 year period of analysis with

minimum continuing intervention.

ES 3 Alternatives *

An initial list of measures was developed including 19 hard structural measures

(i.e. revetments, groins, canal plugs, etc.) and 12 soft-structural measures (i.e. dune

restoration, marsh creation, herbivore control, etc). Qualitative screening of these

measures resulted in the elimination of 15 measures and the retention of 16

measures to be carried forward for a more detailed evaluation in the second level of

screening. These management measures were determined to be consistent with

specific USACE policies for ecosystem restoration, and Federal laws, regulations,

and Executive Orders.

The second level screening effort built on the initial screening process, with an

emphasis on the combinations of measures that could be used to meet the specific

objectives of the Study. As a result of the second level of screening, it was

determined that a combination of beach, dune, and marsh restoration measures

would be needed to achieve the primary objective of restoring geomorphic form and

ecologic function. This screening process resulted in the elimination of seven

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additional measures. The beach, dune, and marsh components, as well as the

measures that could provide supplemental benefits were carried forward.

The final screening effort, which built upon the second level screening process,

evaluated the use of supplementary measures including sand fences, vegetative

planning, herbivory control, breakwaters, terminal groins, and continuous

revetments that would complement the beach, dune, and marsh measures. These

measures were evaluated on an island-by-island basis.

After screening of the measures, five restoration plans, each consisting of a beach,

dune, and marsh component, were developed for the seven islands. The plans were

denoted as Plans A through E:

 Plan A  No-Action Alternative

 Plan B  Minimum Design Plan

 Plan C  Minimum Design Plan plus 5 years of advanced fill

 Plan D  Minimum Design Plan plus 10 years of advanced fill

 Plan E  Minimum Design Plan plus 25 years of advanced fill

Various combinations of islands, restoration plans (Plans A through E) and

supplementary measures (breakwaters, terminal groins, etc.) were evaluated to

determine the best combinations of features (i.e. alternatives) that would meet the

planning objectives and that would be consistent with the 2004 LCA Study and

2007 WRDA authorization. Through an iterative process of plan formulation and

screening, six alternatives were originally recommended for inclusion in the Final

Array of Alternatives. Each alternative is described below.

Alternative 1

Alternative 1, which is the No-Action Alternative, assumes there would be no future

barrier island restoration within the Study Area. The barrier islands will continue

to be subjected to the factors and processes that are contributing to the loss of the

Timbalier and Isles Dernieres barrier island reaches and will result in a direct loss

of the barrier islands to open water. By 2062, Timbalier and East Timbalier will

only have 6 acres of subaerial habitat left. All other islands in the reach will have

disappeared within the 50-year period of analysis.

Alternative 2

Alternative 2 includes the restoration of Timbalier Island to its minimal

geomorphologic form and ecologic function along with 25 years of advanced fill.

Approximately 2,630 acres would be restored for Alternative 2.

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Alternative 3

Alternative 3 includes the restoration of Whiskey Island to its minimal

geomorphologic form and ecologic function along with five (5) years of advanced fill

combined with restoration of Timbalier Island to its minimal geomorphologic form

and ecologic function along with twenty-five (25) years of advanced fill.

Approximately 3,902 acres would be restored for Alternative 3.

Alternative 4

Alternative 4 includes the restoration of Whiskey and Trinity Islands to their

minimal geomorphologic form and ecologic function along with five (5) years of

advanced fill combined with restoration of Timbalier Island to its minimal

geomorphologic form and ecologic function along with twenty-five (25) years of

advanced fill. Approximately 5,051 acres would be restored for Alternative 4.

Alternative 5 (NER Plan)

Alternative 5 (NER Plan) includes the restoration of Raccoon Island to its minimal

geomorphologic form and ecologic function along with twenty-five (25) years of

advanced fill and construction of a terminal groin. This plan also includes

restoration of Whiskey and Trinity Islands to their minimal geomorphologic form

and ecologic function along with five (5) years of advanced fill and restoration of

Timbalier Island to its minimal geomorphologic form and ecologic function along

with twenty-five (25) years of advanced fill. Approximately 5,840 acres would be

restored for Alternative 5 (NER Plan).

Alternative 11

Alternative 11 includes the restoration of Whiskey Island to its minimal

geomorphologic form and ecologic function along with five (5) years of advanced fill.

Approximately 1,272 acres would be restored for Alternative 11.

ES 4 Affected Environment *

The Study Area includes the Isles Dernieres and Timbalier Island reaches located

in Terrebonne and Lafourche Parishes, Louisiana. These barrier islands define the

southern boundary of the Terrebonne Basin and separate the shallow estuarine

bays and saline marshes from the Gulf of Mexico.

Isles Dernieres

The Isles Dernieres reach is approximately 22 miles long and extends from Caillou

Bay east to Wine Island Pass. Raccoon Island, Whiskey Island, Trinity Island, East

Island, and Wine Island, the primary islands that comprise the Isles Dernieres

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barrier island reach, are backed by Bay Blanc, Bay Round, Caillou Bay, and

Terrebonne Bay, and bordered by the Gulf of Mexico on the seaward side. The

islands range from approximately 0.1 to 1.2 miles wide and are typically composed

of a thin sand cap over a thick mud platform. Elevations are generally low and the

islands are frequently overwashed.

Timbalier Islands

The Timbalier reach is comprised of Timbalier Island and East Timbalier Island.

Timbalier and East Timbalier islands are on the western edge of the Lafourche

barrier shoreline and are located about 60 miles southwest of New Orleans,

Louisiana. This barrier island shoreline is approximately 20 miles long and backed

by Terrebonne and Timbalier Bay to the north and delimited by Raccoon Pass to the

east and Cat Island Pass to the west. The islands range from 0.1 to 0.6 miles wide,

with low elevations. The Timbalier Islands support onshore and offshore oil and gas

development and production. Oil and gas production facilities are prevalent in the

East Timbalier Islands, while only a few scattered facilities are present along

Timbalier Island. Oil and gas canals are present on both islands.

The impacts of the Deepwater Horizon oil spill on coastal Louisiana are uncertain

at this time (October 2010). This spill could potentially adversely impact factors

such as changes to existing or baseline conditions.

ES 5 Environmental Consequences *

Six alternative plans (including the No Action Alternative) were carried forward for

detailed analysis based on the results of a cost effectiveness/incremental cost

analysis (CE/ICA). Potential environmental consequences of implementing these

alternatives were compared to the No-Action Alternative (Future Without Project

Conditions). These alternatives were evaluated in terms of potential direct, indirect,

and cumulative impacts to soils, hydrology, water quality and salinity, air quality,

noise, vegetation resources, wildlife and habitat, aquatic resources, fisheries,

essential fish habitat, threatened and endangered species, cultural resources,

aesthetics, recreation, socioeconomics and human resources, and hazardous, toxic,

and radioactive wastes. The following alternatives were evaluated:

 Alternative 1: No Action Alternative

 Alternative 2: Timbalier (Plan E) would restore a net total of 1100 average

annual habitat units (AAHUs).

 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E) would restore a net

total of 1,778 AAHUs.

 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

would restore a net total of 2,406 AAHUs.

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 Alternative 5 (NER Plan): Raccoon with TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E) would restore a net total of 2,883

AAHUs.

 Alternative 11: Whiskey (Plan C) would restore a net total of 678 AAHUs.

The impacts of the Deepwater Horizon oil spill on coastal Louisiana are uncertain

at this time (October 2010). This spill could potentially adversely impact factors

such as changes to Future Without and Future With Project conditions.

ES 6 Public Involvement *

The USACE published a notice of intent to prepare a Supplemental Environmental

Impact Statement (SEIS) for the LCA TBBSR Study in the Federal Register on

December 22, 2008. A public scoping meeting was held on February 10, 2009, in

Houma, Louisiana. A Scoping Report was prepared that compiled comments

received during the meeting as well as written comments submitted during the

comment period.

In addition to the Scoping Meeting, Study updates were provided to the Terrebonne

Parish Coastal Zone Committee and Restore or Retreat, a local non-governmental

coastal advocacy group.

ES 7 Coordination and Compliance *

Following completion of the Final Integrated Feasibility Study and Final

Environmental Impact Statement (FEIS), the Assistant Secretary of the Army for

Civil Works will issue a Record of Decision (ROD) concerning the proposed action.

Full compliance with statutory authorities will be accomplished upon review of the

Final Integrated Feasibility Study (FEIS) by appropriate agencies and the public

and the signing of the ROD, in compliance with the National Environmental Policy

Act (NEPA). The USACE has coordinated with the U.S. Fish and Wildlife Service,

National Marine Fisheries Service and the Louisiana Department of Wildlife and

Fisheries (LDWF) as per the Fish and Wildlife Coordination Act. A coordination act

letter report has been received and the comments incorporated into the Integrated

Feasibility Study and Final Environmental Impact Statement.

ES 8 Areas of Controversy and Unresolved Issues

An area of controversy that exists is the cost-effectiveness of hardened structures,

most notably, rock breakwaters and revetments, in achieving the Study goals.

These measures are supported by the local Parish Government as well as groups

and individuals in the scientific community. Additionally, because the

recommended component of construction does not stop the problems that cause

coastal erosion, there is concern that it is not sustainable.

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The impacts of the Deepwater Horizon oil spill on coastal Louisiana are uncertain

at this time (October 2010). The impacts of the oil spill as well as the various

emergency actions taken to address oil spill impacts (e.g., use of oil dispersants,

creation of sand berms, use of Hesco baskets, rip-rap, sheet piling and other actions)

could potentially impact USACE water resources projects and studies within the

Louisiana coastal area, including the LCA TBBSR Study. Potential impacts could

include factors such as changes to existing, Future Without, and Future With

Project conditions, as well as increased project costs and implementation delays.

The USACE will continue to monitor and closely coordinate with other Federal and

State resource agencies and local sponsors in determining how to best address any

potential problems associated with the oil spill that may adversely impact Study

implementation. Supplemental planning and environmental documentation may be

required as information becomes available. If at any time petroleum or crude oil is

discovered on Study lands, all efforts will be taken to seek clean up by the

responsible parties, pursuant to the Oil Pollution Act of 1990 (33 U.S.C. 2701 et

seq.).

ES 9 Conclusions and Recommendations *

The NER Plan was selected because it represents a system-wide and cost-effective

approach of restoring as many islands within the Terrebonne Basin barrier system

which can be constructed with available sediment sources. A renourishment plan

was also developed for the island to maintain their geomorphologic form and

ecologic function throughout the 50-year period of analysis.

Alternative 5 (Raccoon with Terminal Groin (Plan E) / Whiskey (Plan C) / Trinity

(Plan C) / and Timbalier (Plan E)) was selected as the NER Plan because it is a Best

Buy plan that fulfills the planning objectives of this study. Best Buy plans are the

most efficient plans because they provide the greatest increase in output for the

least increase in costs. The alternative restores the geomorphologic form and

ecologic function of the four islands in the Terrebonne Basin barrier system.

Immediately after construction (Target Year [TY] 1), the NER Plan will add 3,283

acres of habitat (dune, supratidal, and intertidal) to the existing island footprints of

Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing the total size of the

islands to 5,840 acres. This includes approximately 472 acres of dune, 4,320 acres

of supratidal habitat, and 1,048 acres of intertidal habitat. The NER Plan will

require approximately 27.3 mcy of beach material and 18.7 mcy of marsh material

for initial construction. This material will be dredged from a number of offshore

borrow areas designated as South Pelto, Whiskey 3, New Cut, Raccoon, and Ship

Shoal.

The creation of dune, supratidal, and intertidal habitats will provide essential

habitats for fish, migratory birds, and other terrestrial and aquatic species.

Furthermore, by using the proposed borrow areas, the project would increase

sediment input to supplement longshore sediment transport processes along the

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gulf shoreline by mechanically introducing compatible sediment, and increasing the

ability of the restored area to continue to function and provide habitat with

minimum continuing intervention. Sediment placed on Trinity Island would

eventually be transported to Whiskey Island and Raccoon Island as the sediment

moves westward through the system. Raccoon Island would also receive sediment

directly from Whiskey Island.

The NER Plan was also selected because it protects existing critical habitat on

Raccoon and Whiskey Islands. Raccoon Plan E and Whiskey Plan C were designed

to avoid approximately 58 and 286 acres of existing mangroves on the islands,

respectively. This was done in order to minimize the ecologic impact during

construction. Since these two islands are considered to be valuable wildlife habitats

(Isles Dernieres Barrier Islands Wildlife Refuge) and the LDWF is reestablishing a

pelican rookery on Whiskey Island, maintaining adequate areas of healthy beach,

dune, and marsh is particularly important. Raccoon, Whiskey, Trinity, and

Timbalier are also a critical habitat for endangered species including the piping

plover and are a valuable stopover habitat for migratory birds.

In addition to protecting and maintaining precious ecological benefits, the NER

Plan protects existing State investments on the island. For example, Whiskey Plan

C was designed to complement TE-50, which is an existing Coastal Wetlands

Planning, Protection and Restoration Act (CWPPRA) project that was constructed

in 2009. TE-50 created approximately 316 acres of intertidal back-barrier marsh

between the two existing mangrove stands. Restoration of the beach and dune

gulfward of TE-50 will supplement the existing CWPPRA investment.

Raccoon Plan E was designed to complement two separate CWPPRA projects, TE-29

and TE-48. The TE-29 project, which was completed in July 1997, included the

construction of eight segmented breakwaters along the eastern end of the island.

The TE-48 project consists of two phases. Phase A, which included the construction

of eight additional segmented breakwaters and a terminal groin on the eastern end

of the island, was completed in September of 2005. Phase B, which is currently in

the pre-construction phase, will include the construction of a 53-acre marsh along

the backside of the island. The resilience of Raccoon Island Plan E is partially due

to the existing breakwaters from both CWPPRA projects. The plan will help

protected the marsh that will be constructed as part of TE-48.

The mangrove stands and CWPPRA projects on Raccoon and Whiskey Island can be

avoided without undermining the project because they are the only areas of

sufficient elevation to complement the design template and to contribute to the

geomorphologic form and ecologic function of the islands. Avoidance of other

pockets of existing habitat could potentially undermine the project by providing

weak spots in the template. These areas could be more susceptible to breaching

and could accelerate erosion. Therefore, the remaining 124 acres of habitat on

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Raccoon Island and 201 acres on Whiskey Island will be covered with fill material

during construction of the template. Existing habitat on Trinity and Timbalier

Islands can not be avoided without undermining the project. Therefore, the entire

footprints of the islands (564 acres on Trinity and 955 acres on Timbalier) will be

covered with fill material, but will be restored through the vegetative planting

efforts following construction.

Raccoon Island will be renourished at TY30 by adding adequate sediment such that

the dune and supratidal beach acres would be equivalent to that of a newly

constructed Plan B template. Whiskey Island will require two renourishment

intervals. The first will occur at TY20 and will include the addition of the same

amount of dune and supratidal beach habitat that was originally created in TY1.

The second renourishment interval will occur at TY40 and will include the addition

of the same amount of dune and supratidal beach habitat needed to construct a

Plan B template. Trinity Island will be renourished at TY25 by adding the same

amount of dune and supratidal beach habitat that was originally added in TY1.

Timbalier Island will be renourished at TY30 by adding adequate sediment such

that the dune and supratidal beach habitat acres would be equivalent to the acres of

a newly constructed Plan B template.

However, the NER Plan cannot be constructed within the maximum project cost as

authorized by WRDA 2007 and modified according to section 902 of WRDA 1986, as

amended. Therefore, a subset of the NER Plan was selected as the recommended

component of construction. The recommended component of construction

represents an implementable and separable element of the NER Plan, is costeffective, and within the cost and scope of the current authorization. The USACE

will seek additional authorization in order to construct additional increments of the

NER Plan. Due to the highly variable nature of the coastal processes within the

Terrebonne Basin and the limitations of modeling barrier island restoration

performance and response to structures with the modeling program completed in

this study, it is recommended that combined wave and current modeling be

conducted in the preconstruction, engineering, and design (PED) phase on a systemwide level to support the NER Plan.

In order to determine the recommended component of construction from the NER

Plan, the PDT performed additional cost refinements on each island in the NER

Plan. These analyses determined that Trinity Island Plan C and Whiskey Island

Plan C were the only islands plans that could be constructed within the maximum

project cost as authorized by WRDA 2007 and modified according to section 902 of

WRDA 1986, as amended. Previous CE/ICA analysis revealed that both islands

plans, when analyzed separately, were cost-effective. The plans also proved to be

cost-effective when analyzed as a separate alternative (Alternatives 11 and 12) in

the final array.

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The barrier islands provide a critical component of the estuary structure, and are

the first line of defense against marine and weather influences. Whiskey Island is

the closest of the seven barrier islands to the critical marsh habitat located in the

southern-most portion of Terrebonne Parish. If the island were to disappear, the

marsh habitat on the mainland would be susceptible to the direct impacts of

tropical storms and hurricanes.

Although Whiskey Plan C provides slightly fewer Average Annual Habitat Units

(AAHUs) than Trinity Island Plan C (379 net AAHUs vs. 387 net AAHUs), it was

selected as the recommended component of construction due to a number of

qualitative benefits provided by the plan. Whiskey Plan C was designed to avoid

approximately 286 acres of existing mangroves on the island in order to minimize

the ecologic impact during construction. Since the island is considered a valuable

wildlife habitat and the Louisiana Department of Wildlife and Fisheries (LDWF) is

reestablishing a pelican rookery on the island, maintaining adequate areas of

healthy beach, dune, and marsh is particularly important. The island is also a

critical habitat for threatened species including the piping plover and is a valuable

stopover habitat for migratory birds. Furthermore, Whiskey Plan C was designed

to complement TE-50, which is an existing CWPPRA project that was constructed in

2009. TE-50 created approximately 316 acres of intertidal back-barrier marsh

between the two existing mangrove stands. Restoration of the beach and dune

gulfward of TE-50 will help to protect the existing CWPPRA project. Raccoon

Island, which also contains a rare mangrove habitat and is an important rookery,

will benefit from increased sediment deposition as the longshore sediment transport

moves some of the sediment from Whiskey Island westward to Raccoon Island.

Table ES-1 shows a comparison of the NER Plan and recommended component of

construction alternatives.

Table ES-1: LCA TBBSR Study: Comparison of NER Plan and

Recommended Component of Construction

Alt. 11

(Recommend

Component of

Construction)

Alt. 5

(NER Plan)

Net AAHUs 678 2,883

Cost-effective (Yes/No/Best Buy) Yes Best Buy

$Annualized Cost/AAHU * $10,740 $10,100

Project First Cost** $113,000,000 $647,000,000

Federal Share Cost Total $74,000,000 $421,000,000

Non-Federal Share Cost Total $40,000,000 $226,000,000

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Alt. 11

(Recommend

Component of

Construction)

Alt. 5

(NER Plan)

Authorized Cost in WRDA Title VII, Section

7006 (e)(3)(A)

$124,600,000

Maximum Cost Limited by Section 902*** $180,900,000

* Based on preliminary cost estimate, not MCACES cost.

** Includes MCACES costs plus contingency

*** Includes inflation and monitoring and adaptive management costs.

Immediately after construction (TY1), the recommended component of construction

will add 469 acres of habitat (dune, supratidal, and intertidal) to the existing 803-

acre island footprint, increasing the size of the island to 1,272 acres. This includes

65 acres of dune, 830 acres of supratidal, and 377 acres of intertidal habitat.

Components of the recommended component of construction:

 Constructed dune to a height of +6.4 ft North American Vertical Datum

(NAVD) 88 with dune crown of 100 ft

 Beach fill to an elevation of +4.2 ft NAVD 88 with a width of approximately

1300 ft on the gulfward side of the dune and a width of 100 ft on the bay side

of the dune.

 Marsh fill (landward side of the dunes) to an elevation of +2.4 ft NAVD 88.

 Approximately 18,075 ft of sand fencing would be installed

Initial construction of the recommended component of construction will require 8.3

mcy of beach material dredged from Ship Shoal and 0.6 mcy of marsh material

dredged from the Whiskey 3 borrow area.

The recommended component of construction meets the goal of the 2004 LCA Plan

to address critical near-term needs for shoreline restoration for Terrebonne Basin

through simulating historical conditions by enlarging the barrier island (width and

dune crest) and reducing the current number of breaches to ensure the continuing

geomorphic and ecological form and function of the barrier islands. The

recommended component of construction also meets the USACE Principles and

Guidelines of completeness, effectiveness, efficiency, and acceptability, as well as

the Environmental Operating Principles of environmental sustainability,

interdependence, balance and synergy, accountability, knowledge, respect, and

assessing and mitigating cumulative impacts.

A renourishment event will be conducted on Whiskey Island in TY20 and in TY40 in

order to maintain the geomorphic form and ecologic function of the island

throughout the 50-year period of analysis.

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The fully funded cost of the recommended component of construction is

approximately $119,000,000, without renourishment. The two renourishment cycles

will cost an additional $341,000,000. However, renourishment is considered an

O&M cost that will be fully-funded by the non-Federal sponsor and does not count

toward the maximum project cost of $180,900,000 as authorized by WRDA 2007 and

modified according to section 902 of WRDA 1986, as amended.

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TABLE OF CONTENTS

VOLUME VTERREBONNE BASIN BARRIER SHORELINE RESTORATION

INTEGRATED FEASIBILITY STUDY AND FINAL ENVIRONMENTAL IMPACT STATEMENT

1.0 STUDY INFORMATION ................................................................................1-1

1.1 Study Authority .................................................................................... 1-1

1.2 Purpose and Scope ................................................................................ 1-2

1.3 Study Area............................................................................................. 1-2

1.3.1 Isles Dernieres Reach................................................................. 1-3

1.3.2 Timbalier Reach ......................................................................... 1-3

1.4 History of Investigation ........................................................................ 1-5

1.5 Prior Studies, Reports, and Existing Projects ..................................... 1-5

1.5.1 Federal........................................................................................ 1-9

1.5.2 State.......................................................................................... 1-33

1.6 Planning Process and Report Organization....................................... 1-35

1.7 USACE Campaign Plan...................................................................... 1-36

2.0 NEED FOR AND OBJECTIVES OF ACTION ..............................................2-1

2.1 National Objectives............................................................................... 2-1

2.2 Public Concerns..................................................................................... 2-1

2.3 Problems, Needs, and Opportunities ................................................... 2-2

2.3.1 General Problem Statement ...................................................... 2-2

2.3.2 Subsidence .................................................................................. 2-2

2.3.3 Needs .......................................................................................... 2-6

2.3.4 Study Area Opportunities.......................................................... 2-7

2.4 Planning Objectives .............................................................................. 2-8

2.5 Planning Constraints............................................................................ 2-9

2.6 Future Without Project......................................................................... 2-9

3.0 ALTERNATIVES............................................................................................3-1

3.1 Plan Formulation Rationale ................................................................. 3-1

3.1.1 Plan Formulation Rationale ...................................................... 3-1

3.1.2 Plan Formulation Criteria ......................................................... 3-1

3.1.3 Environmental Operating Principles ........................................ 3-1

3.2 Management Measures......................................................................... 3-2

3.2.1 Development of Management Measures ................................... 3-2

3.2.2 Description of Management Measures...................................... 3-3

3.2.3 Screening/Evaluation of Management Measures ..................... 3-7

3.2.4 Value Engineering Analysis .................................................... 3-30

3.2.5 Screening / Evaluation of Borrow Areas ................................. 3-31

3.3 Preliminary Alternative Plans ........................................................... 3-42

3.3.1 Development of Alternative Plans........................................... 3-42

3.3.2 Description of Alternative Plans ............................................. 3-43

3.3.3 Screening/Evaluation of Alternative Plans............................. 3-48

3.3.4 Alternative Plans not Carried Over for Further Analysis...... 3-58

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3.4 Intermediate Array of Alternatives.................................................... 3-59

3.4.1 Alternative 1............................................................................. 3-61

3.4.2 Alternative 2............................................................................. 3-63

3.4.3 Alternative 3............................................................................. 3-63

3.4.4 Alternative 4............................................................................. 3-64

3.4.5 Alternative 5............................................................................. 3-65

3.4.6 Alternative 6............................................................................. 3-66

3.4.7 Alternative 7............................................................................. 3-67

3.4.8 Alternative 8............................................................................. 3-67

3.4.9 Alternative 9............................................................................. 3-68

3.4.10 Alternative 10........................................................................... 3-69

3.5 Comparison of Alternative Plans ....................................................... 3-73

3.5.1 Benefit Analysis ....................................................................... 3-73

3.5.2 Cost Effectiveness and Incremental Cost Analyses................ 3-78

3.6 NER Plan............................................................................................. 3-83

3.6.1 Renourishment ......................................................................... 3-85

3.6.2 Costs.......................................................................................... 3-89

3.6.3 Significance of Ecosystem Outputs.......................................... 3-90

3.6.4 Acceptability, Completeness, Effectiveness, and Efficiency... 3-95

3.6.5 Sustainability ........................................................................... 3-99

3.6.6 Components ............................................................................ 3-100

3.6.7 Design, Environmental, and Construction Considerations.. 3-111

3.6.8 Real Estate Requirements ..................................................... 3-120

3.6.9 Operations and Maintenance Considerations....................... 3-123

3.6.10 Monitoring Plan and Adaptive Management........................ 3-124

3.6.11 Effectiveness of the NER Plan in Meeting Goals and Objectives3-124

3.6.12 Effectiveness of NER Plan in Meeting Environmental Operating

Principles ................................................................................ 3-125

3.6.13 Compensatory Mitigation Measures ..................................... 3-125

3.7 Recommended Component of Construction ..................................... 3-125

3.7.1 Renourishment ....................................................................... 3-127

3.7.2 Costs........................................................................................ 3-129

3.7.3 Significance of Ecosystem Outputs........................................ 3-130

3.7.4 Acceptability, Completeness, Effectiveness, and Efficiency. 3-134

3.7.5 Sustainability ......................................................................... 3-138

3.7.6 Components ............................................................................ 3-139

3.7.7 Design, Environmental, and Construction Considerations.. 3-141

3.7.8 Real Estate Requirements ..................................................... 3-150

3.7.9 Operations and Maintenance Considerations....................... 3-152

3.7.10 Monitoring Plan and Adaptive Management........................ 3-152

3.7.11 Effectiveness of the Recommended Component of Construction in

Meeting Goals and Objectives................................................ 3-152

3.7.12 Effectiveness of Recommended Component of Construction in Meeting

Environmental Operating Principles .................................... 3-153

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3.7.13 Compensatory Mitigation Measures ..................................... 3-153

3.8 Final Array Impacts.......................................................................... 3-153

3.9 Risk and Uncertainty........................................................................ 3-185

3.9.1 Simulation Uncertainties....................................................... 3-185

3.9.2 Weather-related Risks ........................................................... 3-185

3.9.3 Relative Sea-Level Rise Uncertainties.................................. 3-185

3.9.4 Cost Estimate Uncertainties.................................................. 3-188

3.9.5 Recommendations for Future Research ................................ 3-191

3.10 Implementation Requirements......................................................... 3-192

3.10.1 Schedule.................................................................................. 3-192

3.10.2 Implementation Responsibilities........................................... 3-195

3.10.3 Cost Sharing ........................................................................... 3-198

3.10.4 Environmental Commitments ............................................... 3-200

3.10.5 Financial Requirements......................................................... 3-202

3.10.6 Views of Non-Federal Sponsor............................................... 3-203

4.0 AFFECTED ENVIRONMENT .......................................................................4-1

4.1 Environmental Setting of the Study Area ........................................... 4-2

4.1.1 Location ...................................................................................... 4-2

4.1.2 Climate ....................................................................................... 4-3

4.1.3 Geomorphic and Physiographic Setting .................................... 4-5

4.2 Significant Resources.......................................................................... 4-17

4.2.1 Soils and Water bottoms .......................................................... 4-17

4.2.2 Hydrology.................................................................................. 4-25

4.2.3 Water Quality and Salinity...................................................... 4-37

4.2.4 Air Quality................................................................................ 4-40

4.2.5 Noise ......................................................................................... 4-41

4.2.6 Vegetation Resources ............................................................... 4-42

4.2.7 Wildlife and Habitat................................................................. 4-46

4.2.8 Aquatic Resources .................................................................... 4-49

4.2.9 Fisheries ................................................................................... 4-55

4.2.10 Essential Fish Habitat (EFH).................................................. 4-60

4.2.11 Threatened and Endangered Species...................................... 4-64

4.2.12 Cultural and Historic Resources ............................................. 4-76

4.2.13 Aesthetics.................................................................................. 4-83

4.2.14 Recreation................................................................................. 4-85

4.2.15 Socioeconomics and Human Resources ................................... 4-90

4.2.16 Hazardous, Toxic, and Radioactive Wastes .......................... 4-108

5.0 ENVIRONMENTAL CONSEQUENCES.......................................................5-1

5.1 Soils and Water bottoms....................................................................... 5-1

5.1.1 Soils............................................................................................. 5-1

5.1.2 Water bottoms ............................................................................ 5-8

5.2 Coastal Processes and Hydrology....................................................... 5-16

5.2.1 Flow and Water Levels ............................................................ 5-16

5.2.2 Sediment and Erosion .............................................................. 5-25

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5.2.3 Water Use and Supply ............................................................. 5-33

5.2.4 Groundwater............................................................................. 5-35

5.3 Water Quality and Salinity ................................................................ 5-37

5.3.1 Water Quality........................................................................... 5-37

5.3.2 Salinity...................................................................................... 5-43

5.4 Air Quality........................................................................................... 5-48

5.5 Noise .................................................................................................... 5-52

5.6 Vegetation Resources.......................................................................... 5-56

5.6.1 Riparian Vegetation Resources................................................ 5-56

5.6.2 Wetland Vegetation Resources ................................................ 5-62

5.6.3 Upland Vegetation Resources.................................................. 5-70

5.6.4 Submerged Aquatic Vegetation (SAV) .................................... 5-76

5.6.5 Invasive Species  Vegetation.................................................. 5-82

5.7 Wildlife and Habitat ........................................................................... 5-85

5.8 Aquatic Resources............................................................................... 5-95

5.8.1 Benthic...................................................................................... 5-95

5.8.2 Plankton.................................................................................. 5-105

5.9 Fisheries ............................................................................................ 5-110

5.10 Essential Fish Habitat (EFH) .......................................................... 5-118

5.11 Threatened and Endangered Species............................................... 5-126

5.12 Cultural and Historic Resources ...................................................... 5-140

5.13 Aesthetics .......................................................................................... 5-145

5.14 Recreation.......................................................................................... 5-147

5.15 Socioeconomics and Human Resources............................................ 5-152

5.15.1 Population and Housing......................................................... 5-152

5.15.2 Employment and Income ....................................................... 5-155

5.15.3 Community Cohesion ............................................................. 5-158

5.15.4 Environmental Justice........................................................... 5-160

5.15.5 Infrastructure......................................................................... 5-163

5.15.6 Business and Industry ........................................................... 5-166

5.15.7 Traffic and Transportation .................................................... 5-169

5.15.8 Public Facilities and Services ................................................ 5-171

5.15.9 Local Government Finance .................................................... 5-173

5.15.10 Tax Revenue and Property Values ........................................ 5-174

5.15.11 Community and Regional Growth......................................... 5-177

5.15.12 Land Use Socioeconomics....................................................... 5-178

5.15.13 Water Use and Supply ........................................................... 5-185

5.15.14 Navigation .............................................................................. 5-187

5.15.15 Man-Made Resources ............................................................. 5-189

5.15.16 Natural Resources.................................................................. 5-197

5.16 Hazardous, Toxic, and Radioactive Wastes ..................................... 5-202

6.0 PUBLIC INVOLVEMENT..............................................................................6-1

6.1 NEPA Scoping ....................................................................................... 6-1

6.2 Scoping Comments................................................................................ 6-2

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6.2.1 Landowner Involvement ............................................................ 6-4

6.2.2 Non-Governmental Organization (NGO) Involvement............. 6-4

6.2.3 Parish Involvement .................................................................... 6-5

6.3 Public Comments on the Supplemental EIS........................................ 6-5

7.0 COORDINATION AND COMPLIANCE........................................................7-1

7.1 USACE Principles and Guidelines (P&G) ........................................... 7-1

7.2 Environmental Coordination and Compliance .................................... 7-1

7.2.1 U.S. Fish and Wildlife Coordination Act................................... 7-1

7.2.2 Clean Water Act  Section 401 .................................................. 7-5

7.2.3 Clean Water Act  Section 404(b)(1) ......................................... 7-5

7.2.4 Section 122 of the Rivers and Harbors Act ............................... 7-7

7.2.5 Coastal Zone Management Act of 1972 ..................................... 7-7

7.2.6 Endangered Species Act of 1973................................................ 7-7

7.2.7 Magnuson-Stevens Fishery Conservation and Management Act of

1996; and the Magnuson-Stevens Act Reauthorization of 2006

(Essential Fish Habitat)............................................................. 7-8

7.2.8 Clean Air Act  Air Quality Determination .............................. 7-9

7.2.9 National Historic Preservation Act of 1966 .............................. 7-9

7.2.10 Farmland Protection Policy Act (Prime and Unique Farmlands)7-10

7.2.11 Executive Order 13186  Migratory Bird Habitat Protection 7-10

7.2.12 Executive Order 12898  Environmental Justice................... 7-10

7.2.13 Executive Order 13112  Invasive Species ............................. 7-11

7.2.14 Executive Order 11988  Floodplain Management ................ 7-12

7.2.15 Executive Order 11990  Protection of Wetlands ................... 7-12

7.2.16 Uniform Relocation Assistance and Real Property Acquisition Policies

Act of 1970 ................................................................................ 7-12

7.2.17 Louisiana State Rare, Threatened, and Endangered Species, and

Natural Communities Coordination........................................ 7-12

7.2.18 Coastal Barrier Resources Act of 1982.................................... 7-13

8.0 CONCLUSIONS AND DETERMINATIONS.................................................8-1

8.1 Areas of Controversy and Unresolved issues....................................... 8-1

8.2 Conclusions............................................................................................ 8-5

8.3 Recommendations ................................................................................. 8-6

9.0 DISTRIBUTION LIST AND OTHER.............................................................9-1

9.1 Distribution List.................................................................................... 9-1

9.2 List of Preparers ................................................................................... 9-1

9.3 Literature Cited .................................................................................... 9-3

9.4 Glossary............................................................................................... 9-18

9.5 Acronyms, Abbreviations, Symbols, and Initialisms......................... 9-27

ATTACHMENT

ATTACHEMENT 1: NON-FEDERAL SPONSORS LETTER OF INTENT

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APPENDICES

Appendix A  Biological Assessment

Appendix B  USFWS Coordination Letter and Report

Appendix C  NOAA Fisheries Service Coordination Letter

Appendix D  404(b)(1) Water Quality Report

Appendix E  Louisiana Coastal Resources Program Consistency Determination

Appendix F  Programmatic Agreement among USACE, CPRA, SHPO, and ACHP

Appendix G  Responses to Comments

Appendix H  Value Engineering Report

Appendix I  Adaptive Management and Monitoring Plan

Appendix J  Real Estate Plan

Appendix K  Cost Effectiveness / Incremental Cost Analysis

Appendix L  Engineering

Appendix M  Hazardous, Toxic, and Radioactive Waste (HTRW)

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1.0 STUDY INFORMATION

1.1 STUDY AUTHORITY

Title VII of the Water Resources Development Act (WRDA) 2007 authorizes the

Louisiana Coastal Area (LCA) ecosystem restoration program. Included within that

authority are requirements for comprehensive coastal restoration planning,

program governance, a Science and Technology Program, a program for the

beneficial use of dredged material, feasibility studies for restoration plans, project

modification investigations, and restoration project construction, in addition to

other program elements. This authorization was recommended by the Chief of

Engineers Report, dated January 31, 2005.

Under Section 7006 of WRDA 2007, the LCA program has authority for feasibilitylevel reports of six near-term critical restoration features. The excerpt below from

WRDA 2007 outlines the study authority for this report for the LCA Terrebonne

Basin Barrier Shoreline Restoration (TBBSR) Study:

SEC. 7003. LOUISIANA COASTAL AREA.

(a) IN GENERAL.-The Secretary may carry out a program for ecosystem

restoration, Louisiana Coastal Area, Louisiana, substantially in accordance

with the report of the Chief of Engineers, dated January 31, 2005.

SEC. 7006. CONSTRUCTION.

(3) PROJECTS SUBJECT TO REPORTS.

(A) FEASIBILITY REPORTS.Not later than December

31, 2008, the Secretary shall submit to Congress feasibility

reports on the following projects referred to in the restoration

plan:

(i) Multipurpose Operation of Houma Navigation

Lock at a total cost of $18,100,000.

(ii) Terrebonne Basin Barrier Shoreline Restoration

at a total cost of $124,600,000.

(iii) Small Diversion at Convent/Blind River at a

total cost of $88,000,000.

(iv) Amite River Diversion Canal Modification at a

total cost of $5,600,000.

(v) Medium Diversion at Whites Ditch at a total

cost of $86,100,000.

(vi) Convey Atchafalaya River Water to Northern

Terrebonne Marshes at a total cost of $221,200,000.

(B) CONSTRUCTION.The Secretary may carry out the

projects under subparagraph (A) substantially in accordance

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with the plans and subject to the conditions, recommended

in a final report of the Chief of Engineers if a

favorable report of the Chief is completed by not later than

December 31, 2010.

(4) CONSTRUCTION.No appropriations shall be made to

construct any project under this subsection if the report under

paragraph (2) or paragraph (3), as the case may be, has not

been approved by resolutions adopted by the Committee.,

This report is an integrated feasibility study and final environmental impact

statement (FEIS) conducted for the LCA TBBSR Study. This report fulfills the

reporting requirement to Congress of Section 7006(e)(3) which directs the Secretary

of the Army to submit feasibility reports on the six projects included in that section

by December 31, 2008 and authorizes implementation of the projects provided a

favorable Chief of Engineers Report is completed no later than December 31, 2010.

1.2 PURPOSE AND SCOPE

The purpose of the proposed action is to address the goal of the 2004 LCA Plan;

specifically, to address the critical near-term needs for shoreline restoration in

Terrebonne Basin through simulation of historical conditions, which will be

achieved by enlarging the existing barrier islands (width and dune crest) and

reducing the current number of breaches. Additional objectives include analyzing

the current conditions of the barrier islands, assessing impacts from the hurricanes

of 2005 and 2008, and reaffirming the validity of the findings of the Final

Environmental Impact Statement (FEIS) (USACE, 2004b).

The Integrated Feasibility Study and FEIS is based on a thorough review of

existing scientific and engineering reports, as well as geospatial, survey, and

geotechnical data. The report provides a description of the planning process used

to identify the National Ecosystem Restoration (NER) Plan and recommended

component of construction; identifies implementation responsibilities and cost

estimates; and presents a recommendation for construction of the LCA TBBSR

Study. Project planning was of sufficient scope and detail to effectively quantify the

impacts of the NER Plan and recommended component of construction. The Study

considers all reasonable alternatives including alternatives considered in previous

studies, alternatives of varying widths and configurations of barrier shorelines,

consideration of marsh restoration as a platform for barrier shoreline rollover, and

recommendations from interested parties submitted during scoping, public, and

stakeholder meetings.

1.3 STUDY AREA

The Study Area, located in LCA Subprovince 3, provides for the restoration of the

Isles Dernieres and Timbalier Island reaches located in Terrebonne Parish and

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Lafourche Parish, Louisiana. The Study Area is located in the 3rd Congressional

District. The Study Area is shown on Figure 1-1.

1.3.1 Isles Dernieres Reach

The Isles Dernieres Reach represents a barrier island arc approximately 22 miles

long in Terrebonne Parish and extends from Caillou Bay east to Cat Island Pass.

Raccoon Island, Whiskey Island, Trinity Island, East Island, and Wine Island, the

primary islands that comprise the Isles Dernieres barrier island reach, are backed

by Bay Blanc, Bay Round, Caillou Bay, and Terrebonne Bay, and bordered by the

Gulf of Mexico (GOM) on the seaward side. The islands range from approximately

0.1 to 1.2 miles wide and are generally composed of a thin sand cap over a thick

mud platform. Elevations are generally low and the islands are frequently

overwashed (USACE, 2004c).

The Isles Dernieres have been and continue to be an important commercial and

recreational resource for Louisiana and the nation for more than 150 years. The

islands support habitats that are critical to the States commercial fishing industry.

Furthermore, the mineral-rich subsurface below Terrebonne Bay, Lake Pelto, and

Timbalier Bay has supported a high concentration of oil and gas wells.

The first major coastal resort in Louisiana was located here and was washed away

by the great hurricane of 1856 (USACE, 2004c). The Isles Dernieres are also the

location of five Coastal Wetland Planning, Protection, and Restoration Act

(CWPPRA) projects. These projects included: Raccoon Island (TE-29), Whiskey

Island (TE-27), Trinity Island (TE-24), East Island (TE-20), and New Cut (TE-37).

1.3.2 Timbalier Reach

The Timbalier Reach is comprised of Timbalier Island and East Timbalier Island.

The two islands are on the western edge of the Lafourche barrier shoreline and are

located about 60 miles southwest of New Orleans, Louisiana (Figure 1-1). This

barrier island shoreline is approximately 20 miles long and backed by Terrebonne

and Timbalier Bay to the north and delimited by Raccoon Pass to the east and Cat

Island Pass to the west. The islands range from 0.1 to 0.6 miles wide and have low

elevations. The Timbalier Islands support onshore and offshore oil and gas

development and production. Oil and gas production facilities are prevalent along

East Timbalier Island, while only a few scattered facilities are present along

Timbalier Island. Oil and gas canals are present on both islands (USACE, 2004c).

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Figure 1-1. Terrebonne Basin Barrier Shoreline Restoration Study Area

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1.4 HISTORY OF INVESTIGATION

This study was designed to address general barrier island and estuarine ecosystem

restoration problems and opportunities in the Study Area. Numerous regional and

site-specific investigations of erosion and shoreline loss have been conducted along

the Terrebonne Basin barrier island chains. Five of the most comprehensive studies

conducted are listed below:

 Coast 2050 Plan: Toward a Sustainable Coastal Louisiana (LDNR, 1989);

 LCA, Louisiana Ecosystem Restoration Study (USACE, 2004a);

 Louisiana Coastal Protection and Restoration (LACPR) Final Technical Report

(USACE, 2009);

 Ecosystem Restoration and Hurricane Protection in Louisiana (CPRA, 2007);

and

 Evaluation and Recommendation of the Barrier Shoreline Feasibility Study (T.

Baker Smith, 1997).

These comprehensive planning studies are discussed below. Planning for this Study

utilized data from these reports and alternative plans were formulated in

coordination with these plans.

1.5 PRIOR STUDIES, REPORTS, AND EXISTING PROJECTS

A number of prior water resources development efforts are relevant to the LCA

Program. Restoration feature type and location, engineering design, construction

techniques, and performance metrics from these prior efforts have been assessed

and are being considered throughout the project plan formulation process. Table 1-

1 lists these efforts and denotes how each is relevant to the LCA TBBSR Study.

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Table 1-1. Relevance of Prior Studies, Reports, Programs, and Water

Projects to the LCA TBBSR Study

Prior Studies, Reports, Programs, and Water

Projects

Relevance to Terrebonne

Basin Barrier Shoreline

Restoration

Data Sourcea

Consistencyb

HardStructural

Measuresc

Soft-Structural

Measuresd

Comprehensive Planning Studies

Coast 2050 Plan, 1999 XXXX

Louisiana Coastal Area (LCA), Louisiana Ecosystem

Restoration Study, 2004

XXXX

Louisianas Comprehensive Master Plan for a Sustainable

Coast, 2010

XXXX

Louisiana Coastal Protection and Restoration (LACPR)

Technical Plan, 2009

XXX

Ecosystem Restoration and Hurricane Protection in

Louisiana (CPRA), 2007

XXXX

Barrier Island Plan, Evaluation and Recommendation of

the Barrier Shoreline Feasibility Study, T. Baker Smith,

1997

XXXX

Prior Studies, Reports and Water Projects

CWPPRA TE-18, Timbalier Island Planting

Demonstration, NRCS, Completed 1996

XXXX

CWPPRA TE-20, Isles Dernieres Restoration of East

Island, EPA, Completed 1999

XXXX

CWPPRA TE-24, Isles Dernieres Restoration of Trinity

Island, EPA, Completed 1999

XXXX

CWPPRA TE-25, East Timbalier Island Sediment

Restoration, Phase 1, NMFS, Completed 2000

XXXX

CWPPRA TE-30, East Timbalier Island Sediment

Restoration, Phase 2, NMFS, Completed 2000

XXXX

CWPPRA TE-27, Whiskey Island Restoration, EPA,

Completed 2000

XX X

CWPPRA TE-29, Raccoon Island Breakwater

Demonstration, NRCS, Completed 1997

XXX

CWPPRA TE-37, New Cut Dune and Marsh Restoration, XXXX

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Prior Studies, Reports, Programs, and Water

Projects

Relevance to Terrebonne

Basin Barrier Shoreline

Restoration

Data Sourcea

Consistencyb

HardStructural

Measuresc

Soft-Structural

Measuresd

EPA, Completed 2007

CWPPRA TE-40, Timbalier Island Dune and Marsh

Creation, EPA, Completed 2004

XXXX

CWPPRA TE-47, Ship Shoal  Whiskey West Flank

Restoration, EPA, Currently in Engineering & Design

XXXX

CWPPRA TE-48, Raccoon Island Shoreline Protection /

Marsh Creation, NRCS, Under Construction

XXXX

CWPPRA TE-50, Whiskey Island Back-Barrier Marsh

Creation, EPA, Construction Funds Awarded

XXXX

CWPPRA TE-52, West Belle Pass Barrier Headland

Restoration, NMFS/COE, Currently in Engineering &

Design

XX X

CWPPRA TE-53, Enhancement of Barrier Island

Vegetation Demonstration, EPA,

X X

CIAP Nomination  Raccoon Island Breakwaters X X

CIAP Nomination  East Timbalier Island Sediment

Restoration

X X

CIAP Nomination  Ship Shoal: Whiskey West Flank

Restoration

XXXX

CIAP Nomination  Beach and Back Barrier Marsh

Restoration, East and Trinity Islands

X X

CIAP Nomination  Wine Island Restoration X X

CIAP Nomination  East Island Beach, Dune & Marsh

Restoration

X X

CIAP Nomination  East Timbalier Island (Eastern

Section) Restoration

X X

CIAP Nomination  East Timbalier Island Restoration X X

USACE Navigation Projects  Houma Navigation Canal XX X

Beneficial Use of Dredged Material X X

Scoping Study to Evaluate Deepening of Houma

Navigation Channel at Cat Island Pass, Louisiana,

XX X

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Prior Studies, Reports, Programs, and Water

Projects

Relevance to Terrebonne

Basin Barrier Shoreline

Restoration

Data Sourcea

Consistencyb

HardStructural

Measuresc

Soft-Structural

Measuresd

USACE, 2008

Environmental Assessment  Issuance of NonCompetitive Leases for the use of Outer Continental Shelf

Sand Resources from Ship Shoal, Offshore Central

Louisiana for Coastal and Barrier Island Nourishment

and Hurricane Levee Construction, MMS, Draft - 2004

XX X

Laws and Programs

The Coastal Wetlands Planning, Protection and

Restoration Act (CWPPRA), 1990

XXXX

USACE Continuing Authorities Program, 1996 X

The Coastal Impact Assistance Program (CIAP), 2001 &

2005

XXXX

Second Emergency Supplemental Appropriations Act to

Meet the Immediate Needs Arising from the

Consequences of Hurricane Katrina, 2005 (Public Law

109-062)

X X

Department of Defense, Emergency Supplemental

Appropriations to Address Hurricanes in the Gulf of

Mexico, and Pandemic Influenza Act, 2006 (Public Law

109-148)

XXXX

Louisiana Coastal Wetlands Conservation, Restoration

and Management Act, 1989

X

Act 8 of the First Extraordinary Session of 2005 (CPRA) X X

a Relevance of LCATBBSR Study data sources to data sources of prior projects

b Consistency of LCA TBBSR Study measures with prior projects

c Relevance of LCA TBBSR Study hard-structural measures including breakwaters, revetments,

groins, terminal groins, barges/ships, sand fencing, sheet pile, pass closures, and canal plugs, to

hard-structural measures of prior projects

d Relevance of LCA TBBSR Study soft-structural measures including dune/beach restoration, marsh

creation, beach nourishment, subtidal sediment placement, beach closure, vegetation planting,

oyster reefs, spit creation, and canal backfilling to soft-structural measures of prior projects

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1.5.1 Federal

1.5.1.1 Coast 2050 Plan, 1999

In 1998, Federal and State agencies, local governments, academia, numerous nongovernmental groups, and private citizens participated in developing the Coast

2050 Plan (LDNR, 1989), a conceptual plan for restoration of the Louisiana coast.

The Plan was a direct outgrowth of lessons learned from implementation of

restoration projects through CWPPRA and other related programs, and reflected a

growing recognition that a more comprehensive systematic approach to restoring

coastal wetlands was needed. The Plan formed the basis for the May 1999 905(b)

reconnaissance report that preceded the LCA Ecosystem Restoration Study.

1.5.1.2 LCA Ecosystem Restoration Study, 2004

In 2000, the USACE and State of Louisiana initiated the 2004 LCA Plan to address

Louisianas severe coastal land loss problem. The goal of the 2004 LCA Plan is to

achieve and sustain a coastal ecosystem that can support and protect the

environment, economy, and culture of coastal Louisiana and thus, contribute to the

economy and well-being of the Nation. The 2004 LCA Plan focused on lessons

learned from previous Louisiana coastal restoration efforts, the Coast 2050

restoration strategies, and the best available science and technology to develop a

plan addressing the most critical coastal ecological needs. A Final Programmatic

Environmental Impact Statement (FPEIS) was prepared for this study. The

Record of Decision (ROD) for the FPEIS was signed on November 18, 2005. The

FPEIS is hereby incorporated by reference.

The LCA plan maximizes the use of restoration strategies that reintroduce historic

flows of river water, nutrients, and sediment to coastal wetlands, and that maintain

the structural integrity of the coastal ecosystem. Execution of the 2004 LCA Plan

would make significant progress towards achieving and sustaining a coastal

ecosystem that can support and protect the environment, economy, and culture of

southern Louisiana and thus, contribute to the economy and well-being of the

Nation (USACE, 2004a). The 2004 LCA Plan included:

 Specific authorization for implementation of five near-term critical

restoration features for which construction can begin within 5 to 10 years,

subject to approval of feasibility-level decision documents by the Secretary of

the Army;

 Programmatic Authorization of a Science and Technology Program;

 Programmatic Authorization of Science and Technology Program

Demonstration Projects;

 Programmatic Authorization for the Beneficial Use of Dredged Material;

 Programmatic Authorization for Investigations of Modification of Existing

Structures;

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 Approval of ten (10) additional near-term critical restoration features and

authorization for investigations to prepare necessary feasibility-level reports

to be used to present recommendations for potential future Congressional

authorizations; and

 Approval of investigations for assessing six potentially promising large-scale

and long-term restoration concepts.

The LCA TBBSR Study was selected as one of the near-term critical restoration

features for which construction could begin within 5 to 10 years. This feature

originally considered restoration elements for all the major reaches of the

Terrebonne barrier shoreline, however, for inclusion in the near-term plan some

consideration was given to the most critically needed elements of the reach. This

restoration feature provides for the restoration of the Isles Dernieres and Timbalier

Island reaches. This would simulate historical conditions by reducing the current

number of breaches, enlarging (width and dune crest) of the Isles Dernieres and

Timbalier Islands.

1.5.1.3 LACPR Technical Plan, 2009

In response to the destruction caused by Hurricanes Katrina and Rita, the U.S.

Congress directed the Secretary of the Army to develop plans for hurricane risk

reduction and coastal restoration in both Louisiana and Mississippi. In Louisiana,

Congress directed the Secretary of the Army (Public Laws 109-103 and 109-148),

acting through the Chief of Engineers, to:

 Conduct a comprehensive hurricane protection analysis and design in close

coordination with the State of Louisiana and its appropriate agencies;

 Develop and present a full range of flood control, coastal restoration, and

hurricane protection measures exclusive of normal policy considerations for

South Louisiana;

 Consider providing protection for a storm surge equivalent to a Category 5

hurricane; and

 Submit preliminary and final technical reports.

The LACPR Final Technical Report was prepared by the USACE New Orleans

District in response to the Congressional direction for Louisiana. The identification,

selection, and implementation of comprehensive, long range plans for the reduction

and management of hurricane storm damage risk is a highly complex and

collaborative effort. Decisions on these plans will require a high level of engagement

and cooperation at the Federal, State, local, and even individual level. The technical

information to inform some of these long-term decisions is now available through

the LACPR report. Congress directed a technical report rather than a

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reconnaissance or feasibility report as described by normal USACE policy. The

LACPR report presents an array of alternatives for further consideration and

informs decision makers, stakeholders, and the public of the tradeoffs among these

alternatives that should be considered in future decisions in order to maintain

existing risk levels and/or reduce risk along the Louisiana coast.

1.5.1.4 Barrier Shoreline Feasibility Study, 1997

The Barrier Shoreline Feasibility Study (T. Baker Smith, 1992) is the result of a

multi-year barrier shoreline feasibility study authorized by CWPPRA, covering the

barrier islands between the Atchafalaya and Mississippi Rivers. The Final Report

brought together the 12 individual reports that addressed the 11 steps of the

feasibility study. The study addressed both qualitative and quantitative aspects of

the natural/environmental and socioeconomic resources, forecasted trends in those

resources if no actions are taken, identified and assessed various management

alternatives to solve the identified problems, identified various available

engineering solutions to implement the management alternatives, estimated their

costs, and recommended plans for four islands or reaches.

1.5.1.5 CWPPRA

While the Federal government has been concerned with and involved in Louisianas

coastal land loss problem for decades, enactment of CWPPRA in 1990 marked the

first Federal statutory mandate for restoration of Louisianas coastal wetlands.

CWPPRA is described in the Related Laws and Programs section below.

The CWPPRA mandates preparation of an annual Priority Projects List (PPL).

These lists consist of projects that address gulf and inland shoreline protection,

sediment and freshwater diversions, terracing, vegetative plantings, marsh

creation, hydrologic restoration, marsh management, and barrier island restoration.

In the initial stages of the CWPPRA program, the PPL consisted primarily of

projects that were considered under the original Louisiana Coastal Wetlands

Restoration Plan (1992), but later included projects that were nominated or

proposed by the Interagency Planning or Citizen Participation Groups. Once

nominated, these projects are screened and the resulting candidate projects undergo

additional costs and environmental benefits evaluations prior to consideration for

the PPL (LDNR, 1997). In fiscal 2009, CWPPRA received approximately $90

million of Federal funding for the planning and construction of coastal protection

and restoration projects (Gay Browning, personal communication, April 2009).

The following projects located within the Study Area have either been constructed,

are in the engineering and design phase, or are awaiting Phase I/II Authorization

(Figure 1-2):

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Figure 1-2. Location of CWPPRA Projects that have been Authorized in Planning Unit 3a

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CWPPRA Projects That Have Been Constructed

TE-18 Timbalier Island Planting Demonstration Completed July 1996

TE-20 Isles Dernieres Restoration East Island Completed June 1999

TE-24 Isles Dernieres Restoration Trinity Island Completed June 1999

TE-25 East Timbalier Island Sediment Restoration Phase 1 Completed Jan. 2000

TE-27 Whiskey Island Restoration Completed June 2000

TE-29 Raccoon Island Breakwater Demonstration Completed July 1997

TE-30 East Timbalier Island Sediment Restoration Phase 2 Completed Jan. 2000

TE-37 New Cut Dune and Marsh Restoration Completed July 2007

TE-40 Timbalier Island Dune and Marsh Creation Completed Dec. 2004

TE-48 Raccoon Island Shoreline Protection/Marsh

Creation

Phase A Completed Sept. 2005

TE-50 Whiskey Island Back Barrier Marsh Creation Completed Sept. 2009

CWPPRA Projects Authorized for Construction

TE-48 Raccoon Island Shoreline Protection/Marsh

Creation-Phase B

Pre-Construction

CWPPRA Projects Waiting Phase I/II Authorization

TE-47 Ship Shoal: Whiskey West Flank Restoration Engineering & Design

TE-52 West Belle Pass Barrier Headland Beginning Engineering and

Design

TE-53 Enhancement of Barrier Island Vegetation

Demonstration

Waiting Phase

A brief summary of each CWPPRA project is presented herein. Additional

information (project location, restoration feature types, cost, benefits, and year of

completion) related to these projects can be found in the Louisiana Coastal

Wetlands Conservation and Restoration Task Force General Fact Sheets. It should

be noted that most CWPPRA projects do not provide funding for long-term postconstruction monitoring and limited post-construction monitoring is accomplished

by the Office of Coastal Protection and Restoration (OCPR) when funding becomes

available. Success of CWPPRA projects is difficult to ascertain in some instances.

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TE-18 Timbalier Island Plantings Demonstration

TE-18 was a sand fence demonstration project that included vegetative plantings

along approximately 7,400 linear ft of the gulf shoreline of Timbalier Island. The

goals of the project were to increase the elevation of the island and its vegetation

cover through the use of sand fencing and vegetative plantings or combinations of

both. The project was completed in July 1995 with additional plantings conducted in

July 1996. Results of the project demonstrate that sand fencing and vegetative

plantings should be an integral part of sand management of the barrier islands.

The project has helped formulate better practices in the establishment of sand

fencing and the selection of vegetative species (LDNR, 2006a).

TE-20 Isle Dernieres Restoration  East Island

The objectives of the project were to close existing breaches within the project area,

increase the elevation and width of the island, and restore the back barrier marsh.

TE-20 involved the construction of temporary perimeter containment dikes using

borrow material from Lake Pelto and Whiskey Island Pass to hydraulically fill the

dune and marsh templates. The target dune and marsh elevations were +8.0 and

+2.0 ft North American Vertical Datum 1988 (NAVD 88), respectively.

Approximately 242 acres of dune and wetland habitat were created. The project

was completed in October 1998. The restoration efforts on East Island successfully

increased the islands elevation and width, yet post-construction storms (Tropical

Storm Isidore and Hurricane Lili) reduced the overall volume of the island (LDNR,

2007a).

Additional monitoring of East Island was performed following Hurricanes Gustav

and Ike in 2008. Visual observations were made at established stations reaching

from the existing shoreline to the back-barrier marsh. The observations indicated

that the hurricane events caused a considerable amount of shoreline erosion.

Severe overwash was observed on the eastern end, contributing to a loss of

approximately 3,000 ft of the newly constructed island template. Due to a lack of

established marsh behind the island, the marsh did not properly capture the

rollback of the dune (OCPR, 2008b). However, no breaches were observed.

TE-24 Isle Dernieres Restoration  Trinity Island

The objectives of the project were to close existing breaches within the project area,

increase the elevation and width of the island, and restore back barrier marshes.

TE-24 involved the construction of temporary perimeter containment dikes and

using borrow material from Lake Pelto and Whiskey Island Pass to hydraulically

fill the dune and marsh templates. The target dune and marsh elevations were

+8.0 and +2.0 ft NAVD 88, respectively. Approximately 353 acres of dune and

wetland habitat were created. The project was completed in May 1999. Similar to

the TE-20 project, the Trinity Island restoration project succeeded its goal of

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increasing the island elevation and width, yet the post-construction storms reduced

the overall volume of the island (LDNR, 2007b).

The monitoring efforts conducted as part of TE-20 (East Island) were also used to

assess the impacts of Hurricanes Gustav and Ike on the newly constructed template

on Trinity Island. As with East Island, there was a considerable amount of

shoreline erosion and overwash caused by the storms. The severe overwash

contributed to a loss of 1200 ft of template on the western end of the island.

However, no breaches were observed and the island has primarily remained above

its pre-construction elevations (OCPR, 2008c).

TE-25 / TE-30 East Timbalier Sediment Restoration  Phases 1 & 2

TE-25 (Phase 1) and TE-30 (Phase 2) were restoration efforts with emphasis on the

eastern half and western half of the island, respectively. The restoration included

the creation of a 200-ft wide dune, a 600-ft wide back barrier marsh platform,

rubble rock revetment, sand fencing, and vegetative planting. The target dune and

marsh elevations were +5.0 and +2.0 ft NGVD 29, respectively. The dune was

stabilized with a 7,000-ft long rock revetment placed along its gulfward face.

Construction was completed in December 1999.

The effective restoration of East Timbalier Island was hampered by poor fill

material selection and a design that lacked a fronting beach to protect the dune.

These factors may have resulted in the development of several overwash segments

along the island. Furthermore, the use of a rock revetment may not be a feasible

approach to dune protection because as the island experiences the natural process

of rollover, during which the rocks become disjointed from the shoreline. The

disjointed rocks diffract and refract waves in abnormal patterns, thereby disrupting

the longshore transport patterns (LDNR, 2005).

TE-27 Whiskey Island Restoration

The objective of the restoration was to close the breach at Coupe Nouvelle and

thereby fortify the Gulf shoreline from Coupe Nouvelle to the eastern end of the

island. Target elevations of the closure ranged from a maximum of +4 ft to a

minimum of +1 ft NAVD 88. Construction was completed in July 1999. The

restoration efforts on Whiskey Island achieved its goal of increasing the height and

volume of the island. Tropical Storm Isidore and Hurricane Lili reduced the volume

of the island but the island did remain intact and provided some protection for the

mainland areas (LDNR, 2004).

TE-29 Raccoon Island Breakwaters Demonstration

The objectives of the project were to reduce the rate of shoreline retreat on the

eastern end of the island and to protect critical bird nesting habitat. Eight detached

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and segmented breakwaters were constructed in July 1997 to promote sediment

deposition along the beach and upper shore face by decreasing the incident wave

energy landward of the breakwaters, and thereby reduce the rate of shoreline

retreat. Preliminary data suggest breakwater-induced changes to local wave

propagation and attenuation may have resulted in cross-shore sediment trapping

and the emergence of sand bodies directly landward of the breakwaters (LDNR,

1999).

TE-37 New Cut Dune and Marsh Restoration

The objective of the restoration was to close the breach between Trinity and East

Islands, and thereby increase the structural integrity of eastern Isles Dernieres by

restoring the littoral drift and adding sediment in the nearshore system. The

breach was closed by hydraulically dredging approximately 850,000 cy of sediment

from the borrow area, creating an 8,000-ft dune platform with an elevation

matching those of the existing Trinity and East Island elevations. In addition to the

sediment fill, 17,000 ft of sand fencing was installed and nine species of native

barrier island vegetation were planted on the marsh platform (LDNR, 2007c).

TE-40 Timbalier Island Dune and Marsh Restoration

The objectives of the restoration plan were to restore 2.2 miles of the beach and

dune and create a marsh platform through the use of sediment dredged from a

nearby borrow area in Little Pass. The constructed dune consisted of a crest width

of 400 ft at an elevation of +8.0 ft NAVD 88. Beach fill extended an additional 225

ft from the toe of the berm. The elevation of the beach ranged from +5.0 ft NAVD

88 at the toe of dune to +3.0 ft NAVD 88 on the gulf side. An 800-ft wide marsh

platform was constructed at an average elevation of +1.4 ft NAVD 88.

Approximately 2,750 linear ft of sand fencing was also installed along the length of

the project. Construction was completed in December 2004. (LDNR, 2006b).

Beginning in March 2006, approximately 11,500 ft of sand fencing was added to the

restoration project with 2,000 ft of the easternmost fencing being relocated to four

alternate locations as a result of the erosion caused by Hurricanes Katrina and Rita

(LDNR, 2006c). Operations, maintenance, and monitoring reports have not been

published by OCPR.

TE-47 Ship Shoal: Whiskey West Flank Restoration

The project objectives included: 1) restore the integrity of the West Flank of

Whiskey Island to retain its structural function; 2) rebuild the natural framework to

provide a separation of the Gulf and estuary; 3) create a continuous protective

barrier for back bays and inland marshes; and 4) strengthen the longshore

transport of sediment for continuous island building through the introduction of

new sediment from offshore. To aid in the retention of the restoration fill

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sediments, sand fencing and vegetative plantings are proposed (USEPA, 2005).

Phase I of the CWPPRA process, Engineering and Design, has been completed;

however, due to construction funding, Phase II was not immediately recommended

and is currently pending.

TE-48 Raccoon Island Shoreline Protection / Marsh Creation

The project was planned as two separate construction phases, Phases A and B. The

objective of Phase A was to significantly reduce the wave energy impacting the gulf

shoreline through the use of eight segmented breakwaters as a continuation

westward of the original eight constructed as part of TE-29. The addition of a

terminal groin on the eastern most end of the island extending from the shoreline to

the existing breakwater eliminated the tidal currents flowing between the existing

breakwaters and the shoreline. Phase A was completed in 2005. The objective of

Phase B is to create 60 acres of emergent and intertidal wetlands on the northeast

quadrant of the island with hydraulically dredged material. The filled area will be

planted with native species based on finished elevations of the subaerial and

intertidal areas.

TE-50 Whiskey Island Back Barrier Marsh Creation

The goal of the project is to increase the longevity of the previous TE-27 restoration

effort by increasing the islands width. The project consisted of increasing the

marsh elevation to at least +2.5 ft NAVD 88. The exiting dune feature was also

supplemented to increase the crest width to 100 ft and the height to +6.0 ft NAVD

88. Construction was completed in October 2009. Following construction of the

dune feature, sand fencing was constructed parallel to the gulfward face and 30 ft

south of the centerline along the length of the newly restored dune. Vegetative

planting was conducted in order to stabilize the newly constructed dune and marsh

platforms (LDNR, 2009). Operations, maintenance, and monitoring reports have not

been published by OCPR.

TE-52 West Belle Pass Barrier Headland Restoration

The goal of this project is to reestablish the West Belle Pass headland by rebuilding

a large portion of the beach, dune, and back barrier marsh. Approximately 2 mcy of

dredged sand, and 1 mcy of finer material will be used to rebuild nearly 9,300 ft of

beach and dune and 150 acres of marsh respectively. Additionally, native

vegetation plantings will be used to assist in the stabilization of the rebuilt marsh

and dune habitats (LDNR, 2009). TE-52 is currently waiting funding authorization.

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TE-53 Enhancement of Barrier Island Vegetation Demonstration

The goal of this demonstration project is to develop cost-effective methods for

enhancing vegetative establishment and growth on barrier island restoration

projects. Currently, this project is in the planning phase. Two possible project sites

have been proposed  site of the Timbalier Island Dune and Restoration project (TE40), and the New Cut Dune and Marsh Restoration project (TE-37) site (LDNR,

2009b). TE-53 is currently waiting funding authorization.

Evaluation of CWPPRA Projects

While many of the CWPPRA projects implemented throughout the Terrebonne

Basin Barrier Shoreline have been effective in reducing coastal erosion, many have

not been able to withstand the considerable impacts of the recent hurricanes. One

reason for this is that the CWPPRA projects are typically designed for a 20-year

duration and are nearing the end of their expected life. The prescribed budgets for

CWPPRA projects will not support large-scale island restoration plans that are

capable of withstanding major weather events. Therefore, the projects are smaller

in scale and typically address a specific deficiency on the island. Furthermore,

CWPPRA budgets typically do not support a monitoring plan to evaluate the

effectiveness of the projects. However, the projects appeared to have been successful

in meeting their project-specific goals of reducing land loss on the islands.

Fortunately, the authorized budget for the LCA TBBSR Study will support a larger

restoration effort. During the plan formulation phase of the project, the project

delivery team (PDT) was able to capitalize on lessons learned from past CWPPRA

projects in order to determine the most cost-effective means of maximizing habitat

benefits on the islands. One major lesson learned from the in-situ investigations of

the islands and the existing CWPPRA projects was that stand-alone measures were

not a viable means of meeting the goals of the project. Therefore, the PDT focused

on combinations of measures. By the end of the plan formulation phase, the PDT

concluded that each restoration plan must include a beach, dune, and marsh

component in order to meet the project goals of restoring the islands geomorphologic

form and ecologic function (see Chapter 3). The in-situ investigations also revealed

that the project features were not sustainable. Therefore, the PDT assessed the use

of renourishment as an O&M activity to increase the longevity of the island plans.

Not only is this approach expected to provide more habitat benefits over a longer

period of time, it will also bolster existing CWPPRA projects on the islands.

The PDT recognizes the value of a monitoring and adaptive management plan and

have thus accounted for the development and execution of a plan in the budget.

Monitoring plans provide critical data used to evaluate the effectiveness of a project

in meeting goals and objects. This data can be used to assess the validity of the

parameters used in the design of the project (i.e. erosion rates, sea level rise rates,

etc.) and to optimize the input parameters of future projects. In some situations,

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real time monitoring data can be used by stakeholders to adaptively manage the

project to maintain their effectiveness.

1.5.1.6 Coastal Impact Assistance Program

The Coastal Impact Assistance Program (CIAP) is a grant program authorized by

Congress in 2001 to provide assistance to states in mitigating impacts from Outer

Continental Shelf (OCS) oil and gas production. The Minerals Management Service

(MMS) oversees and administers this grant program. Each oil and gas producing

state is allocated their share of funds based on the states qualified outer

continental shelf revenue generated off of its coast in proportion to the total

produced by all eligible states.

In 2001, Louisiana received a one-time allocation from the CIAP of $26.4 million,

which was used to fund various State and local coastal activities and projects

including: monitoring, assessment, research, and planning; habitat, water quality,

and wetland restoration; coastline erosion control; and control of invasive nonnative plant and animal species (USACE, 2004a). Nominated CIAP projects within

the Project area are identified in Figure 1-3 and described in the following subsections. Additional information (project location, restoration feature types, cost,

benefits, and year of completion) related to these CIAP projects can be found in the

general fact sheets and selection criteria documentations provided in Attachment F.

Section 384 of the Energy Policy Act of 2005 authorized an additional $250 million

for each of the fiscal years 2007 through 2010 to be distributed to oil and gas

producing states. In 2007, Louisiana developed a four year plan to submit grant

applications for costal impact projects. Consequently, Louisiana received

$127,547,898.57, $120,911,588.83, and $119,663,560.77 in annual allocations in

2008, 2009, and 2010, respectively. The following projects were considered for

construction as part of CIAP.

Raccoon Island Breakwaters

This project proposes to increase the number of rock breakwaters from the 16

breakwaters constructed on previous CWPPRA projects (TE-29 and TE-48) to 32.

The installation of these breakwaters would provide protection for the western

portion of the island and spit (LDNR, 2008a).

Ship Shoal: Whiskey Island West Flank Restoration

The project objectives included: 1) restore the integrity of the West Flank of

Whiskey Island to retain its structural function; 2) rebuild the natural framework to

provide a separation of the Gulf and estuary; 3) create a continuous protective

barrier for back bays and inland marshes; and 4) strengthen the longshore

transport of sediment for continuous island building through the introduction of

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new sediment from offshore. To aid in the retention of the restoration fill

sediments, sand fencing and vegetative plantings are proposed (USEPA, 2005).

This project was presented at the CWPPRA PPL 11 (TE-47) planning round.

Engineering and design have been completed and Phase II (construction) funding

was requested in December 2005, but the project was not selected. This project

meets the Coast 2050 strategy of restoring and maintaining barrier islands in

addition to meeting the restoration goals identified by the Strategic Plan for Coastal

Restoration adopted by the Terrebonne Parish Coastal Zone Management and

Restoration Advisory Committee (LDNR, 2008c).

Beach and Back Barrier Marsh Restoration, East and Trinity Islands

The proposed beach and back barrier marsh restoration project on East and Trinity

Islands would restore a total of 146 acres of beach and dune habitat and 533 acres

of back barrier marsh. This project was presented at the CWPPRA PPL 16 in

January 2006, but was not selected for continued investigation.

Wine Island Restoration

This project was nominated by the Louisiana Department of Wildlife and Fisheries

(LDWF) and proposes to increase the size of Wine Island and provide for

sustainability through the use of hydraulically dredged material from the Houma

Navigation Canal. This island provides some protection to the back-bay area and is

important to shorebirds (LDNR, 2008d).

East Timbalier Island Restoration

The goal of the project is to reestablish the historic barrier island separating the

bay from the gulf, thereby adding protection to interior areas. The proposed project

features are the creation of approximately of 3,200 linear feet of segmented

breakwaters in the eastern end of the project area by salvaging rocks from the

existing rock dikes along the southern boundary of the island; depositing

hydraulically dredged sand behind the breakwaters to create approximately 190

acres of supratidal habitat, depositing hydraulically dredging sand to create

approximately 180 acres of intertidal habitat on the bay side of the island;

vegetative planting on both the dune and marsh habitat; and 8,200 linear feet of

sand fencing on the created dune.

The project will benefit the oil and gas facilities operated by Maritech Resources,

Inc. These facilities were exposed to the GOM during Hurricane Katrina. Maritech

has stated that they would assist in the funding of maintenance after the island is

restored (LDNR, 2008f).

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East Timbalier Island Sediment Restoration

Hurricanes Katrina and Rita of 2005 further damaged the island, indicating the

urgency at which action must be taken. This project plans to build on CWPPRA

projects TE-25 and TE-30 by using modern search techniques to find sufficient

sediment and sand sources to close a breach in the island and rebuild a larger,

wider dune and beach along the island that will be more sustainable. In addition,

marsh will be created or maintained where necessary behind the dunes to ensure a

uniform width along the length of the island (LDNR, 2008b).

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Figure 1-3. Location of Proposed CIAP Projects (LDNR, 2009c)

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1.5.1.7 USACE Navigation Projects

There are a number of federally maintained waterways in the vicinity of the LCA

TBBSR Study Area. The most important of these in terms of potential direct and

indirect impacts on the Terrebonne Basin barrier islands is the Houma Navigation

Canal (HNC). This canal, which is approximately 37 miles long, originates in

Houma, Louisiana, descends south, and enters the GOM between East Island and

Timbalier Island in what is referred to as Cat Island Pass. The HNC currently

undergoes maintenance dredging in the inland portions every 8 years; the bay

portions every 2 years; and the bar channel section every 2 years. A HNC

Deepening Re-evaluation Study is being conducted in response to requests from the

Terrebonne Port Commission to deepen the HNC from -18 ft to -20 ft NAVD 88. A

preliminary data review revealed that Cat Island Pass and Timbalier Island have

stabilized over the last 70 years and that the dredging of an approximate 13 mcy of

sediment from a 3.6 mile stretch of the HNC near Timbalier Island would create an

imbalance in the littoral system. The natural processes of longshore sediment

transport to the west would most likely erode the adjacent barrier island and

protective shoals as the channel and island try to reach a quasi-equilibrium state. It

is recommended that the sediment dredged from the Pass be placed on the eastern

gulf side of the adjacent island such that the placed sediment would supplement the

longshore transport. In addition, mixed sediments could be placed on the bay sides

of the adjacent islands to promote back-barrier marsh creation. (Lee and Khalil,

2007 and Rosati, 2008). A decision as to which island (Timbalier or East) should

receive the fill must await further refinement of the sediment budget for Cat Island

Pass and a decision on the final alignment of the HNC through the Pass. At this

point there are sound arguments supporting sand placement on either island (Lee

and Khalil, 2007 and Rosati, 2008).

1.5.1.8 Beneficial Use of Dredged Material (BUDMAT)

The USACE MVN has the largest annual channel operations and maintenance

(O&M) program within the USACE, with an average of 64.0 mcy of material

dredged annually. Currently, approximately 24% of the material dredged under

USACEs O&M program is used beneficially within the Federal standards. The

Federal standard refers to the least costly alternative identified by the USACE that

is consistent with sound engineering practices and meets all of the Federal

environmental standards established by Section 404 of the Clean Water Act of 1972

and Section 103 of the Marine Protection, Research, and Sanctuaries Act of 1972, as

amended. Application of the Federal standard constitutes the base disposal plan for

a navigation project. Funds from the BUDMAT Program would be used for disposal

activities associated with separate, cost-shared, ecosystem restoration beneficial use

projects that are above and beyond the disposal activities that are covered under

the USACE O&M maintenance dredging Federal standard.

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The BUDMAT study area is Louisianas coastal area from Mississippi to Texas.

Louisiana parishes included in the study area include Ascension, Assumption,

Calcasieu, Cameron, Iberia, Jefferson, Lafourche, Livingston, Orleans,

Plaquemines, St. Bernard, St. Charles, St. James, St. John the Baptist, St. Martin,

St. Tammany, Tangipahoa, Terrebonne, and Vermilion.

The following nine authorized Federal navigation channels represent the most

significant opportunities for additional beneficial use of dredged material in coastal

Louisiana:

 Barataria Bay Waterway, LA

 Mississippi River, Outlets at Venice, LA  Tiger Pass and Baptiste Collette

 Mississippi River, Baton Rouge to the Gulf of Mexico, LA  Southwest Pass and

South Pass

 Atchafalaya River and Bayous Chene, Boeuf, and Black, LA

 Calcasieu River and Pass, LA

 HNC, LA

 Bayou Lafourche, LA

 Mermentau River, LA

 Freshwater Bayou, LA

Of those listed, two are of major significance to the LCA TBBSR Study. The first is

the HNC, a primary navigation route that bisects the project area at approximately

2 miles from both Wine and Timbalier Islands, and serves as a potential source of

beneficially used material. The second is Bayou Lafourche, which is at the far

eastern periphery of the project area, approximately 3 miles from East Timbalier

Island, and also serves as a potential source of beneficially used material.

The 2004 LCA Plan recommended authorization of $100 million in programmatic

authority for the additional funding needed for beneficial use of dredged material

generated by existing programs. Based on the appropriated funds and a 10-year

period of implementation, it is expected that beneficial use of dredged material

could attain 21,000 acres of newly created wetlands, which represents a significant

opportunity to contribute to the accomplishment of the LCA objectives.

1.5.1.9 Sand Source Studies

In a 1991 report, Suter, et al. identified and described many of the previously

surveyed and/or utilized nearshore sediment areas in the southeast portion of

Coastal Louisiana. Though these potential borrow areas line the immediate gulf46
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and bay-sides of the Terrebonne Basin barrier islands, only the gulf-side areas are

being considered for this study. The State now strongly discourages bayside

sediment dredging because of the potential for the borrow areas to adversely affect

the barrier islands ability to migrate. Furthermore, borrow areas could potentially

serve as sediment sinks in a sediment-starved system.

In April, 2004, the U.S. Department of the Interior, MMS published an

Environmental Assessment titled Issuance of Non-Competitive Leases for the Use of

Outer Continental Shelf (OCS) Sand Resources from Ship Shoal, Offshore Central

Louisiana for Coastal and Barrier Island Nourishment and Hurricane Levee

Construction (MMS 2004). The assessment analyzed the proposed dredging of

approximately 14 mcy of sand for coastal and barrier island restoration and flood

levee construction from within two areas: Ship Shoal OCS area Blocks 87, 88, 89,

94, and 95; and South Pelto OCS area Blocks 12, 13, 14, 18, and 19. These blocks

are located approximately 10 miles south of the Terrebonne Basin barrier islands.

This report relied on work done in previous investigation, most notably, Stone

(2000) and Stone and Xu (1996) to assess direct impacts of sand mining on wave

transformation over Ship Shoal. Stone and Xu (1996) conducted a wave modeling

analysis to evaluate the effects of large-scale removal of sand from various portions

of Ship Shoal. The approach used in the 1996 study centered on the removal of the

entire shoal complex using the available bathymetric data for the shoal and

surrounding area. The total volume of sand numerically extracted from the shoal

for the modeling analysis was over 1.4 billion cy which included up to a 20-ft thick

section of sand being removed from the western portion of the shoal. The model

runs indicated spatial differences in the magnitude of wave heights across the

shoal. The magnitude in wave heights due to shoal removal were less on the east

side of the shoal compared to the west side. Wave height changes on the east side of

the shoal were reported to be insignificant during severe storms and even less

noticeable under fair weather conditions. During severe storm conditions, the model

indicated wave breaking does not occur on the east end of the shoal near South

Pelto Blocks 12 and 13 because of the greater water depths. The model results did

show some increased wave heights in the central and western portions of the shoal

but the overall model results indicated that the entire removal of the shoal will not

have a significant impact on wave energy conditions along the nearshore zone

(MMS 2004).

The report referenced a second field study (Stone 2000) that reported that the shoal

plays an important role in mitigating the wave field off Coastal Louisiana but that

the model may overpredict wave heights by 6 to 24 percent. The report suggests

that removal of large quantities of sand will not significantly influence wave

conditions in the nearshore zone because the increase in wave energy is limited to

the leeward flank of the shoal (MMS 2004).

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Based on the modeling analysis, the MMS Environmental Assessment concluded

that dredging 14 million cy of material will have no significant impact on local wave

and currents.

In April, 2009, MMS published a second report titled Environmental Investigation

of the Long-Term Use of Ship Shoal Sand Resources for Large Scale Beach and

Coastal Restoration in Louisiana Wave Conditions (Stone et al. 2009). The report

was prepared by the Coastal Studies Institute & Department of Oceanography and

Coastal Sciences, Louisiana State University (LSU) and the LACES.

This was a collaborative research effort that included a physical oceanography and

a biological group (meiofauna group and a macroinfauna/blue crab group). This

report looks at the interplay between the physical processes and the benthic

biological habitat over Ship Shoal.

The first six chapters of this report focused on geotechnical characteristics, stormdriven sediment dispersion, wave transformation, and lastly, morphodynamic

differences between sandy and muddy bottom portions of the shoal. The physical

portion of the report culminated with a chapter on the impacts of sand removal on

hydrodynamics and sediment transport which is summarized below.

This study utilized state-of-the-art numerical models to investigate the impacts of

sand mining on hydrodynamics and sediment transport on Ship Shoal using two

case studies. Case study A compared the hydrodynamics of the region under two

bathymetric configurations: one with the shoal and the other with the shoal

completely removed (i.e. large scale mining scenarios). Case study B utilized four

different sand mining scenarios (i.e. small scale mining scenarios) which mimicked

proposed restoration project borrow area configurations (Table 1-2). Specifically,

they examined wave, current variability, and sediment transport over the shoal

under different barrier island restoration/mining scenarios under a winter storm

and tropical cyclone event. The researchers looked at mining at three areas of Ship

Shoal, namely, South Pelto Blocks 12 and 13, Ship Shoal Blocks 88 and 89, and

Ship Shoal Blocks 84, 85, 98, and 99.

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Table 1-2. Ship Shoal Mining Scenarios (Stone et al. 2009).

Case

Sand

Volume

(m3)

Sand

Volume

(cy)

Mining

Area

Excavation

Depth (ft)

Restoration

Target

B-1 7,650,000 10,000,000

South

Pelto

12/13

0.8 Caminada

B-2 13,760,000 18,000,000

South

Pelto

12/13

1.4 Caminada,

Whiskey/Trinity

B-3 6,120,000 8,000,000

Ship

Shoal

88/89

0.7 Whiskey/Trinity

B-4 9,180,000 12,000,000

Ship

Shoal

88/89

1.0 Entire Isles

Dernieres

B-5 9,180,000 12,000,000

Ship

Shoal

84/85,

98/99

1.2 Entire Isles

Dernieres

Large-scale Mining Scenario

The modeling results indicated that Ship Shoal has significant influence on wave

dissipation but suggests that neither large-scale nor small-scale sand mining should

result in abrupt changes in current patterns. The results indicated that large-scale

sand dredging will have spatially profound impacts on waves as shown on Figure 1-

4 as well as on sediment suspension. Wave height attenuation of 22% was computed

for waves crossing over the shoal from the south which indicates the effectiveness of

the shoal in shielding the coast from storm events. Furthermore, changes in wave

transformation and sediment suspension suggest that large-scale sand mining will

enhance fluid mud accumulation on the shoal which would adversely affect the

associated benthic community. Based on this analysis, large scale mining of Ship

Shoal was not recommended. However, it should be noted that this model looked at

the extreme worst-case scenario of complete removal of the shoal. This scenario is

not realistic due to the required setbacks associated with oil and gas infrastructure

located on the shoal.

Small-scale Mining Scenario

The results indicated that small-scale sand mining based on the sand mining

scenarios presented in Table 1-3 is not expected to profoundly impact

hydrodynamics and sediment transport over the shoal. The model showed that

waves were higher without the shoal than with the shoal. The small-scale scenarios,

which removed between 7.68 and 13.76 mcy of sand, had only minor effects on wave

heights.

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Figure 1-4. Wave height and vector distributions for case Study A: (a, b) HS=6m, TP =11s, Wave

direction=135 (degree). (c,d) HS=3m, TP =7s, Wave direction=135 (degree), (e,f) HS=1m, TP =5s, Wave

direction=135 (degree). Top figures represent the results with the shoal and bottom figures representthe result without the shoal (Stone et al. 2009).

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The results indicated that small-scale sand mining based on the sand mining

scenarios presented in Table 1-3, is not expected to profoundly impact

hydrodynamics and sediment transport over the shoal.

Table 1-3. Maximal difference in magnitude of hydrodynamic parameters

between actual bathymetry and hypothetical bathymetry. Top low;

Maximal difference in absolute magnitude of each parameter. Bottom low:

Maximal values in magnitude of each parameter during model duration

(Stone et al. 2009).

Storm Case Wave height

Surface

currents

(m/sec)

Bottom

currents

(m/sec)

RI

N m-2

Winter storms

B2 0.09

1.19

0.17

0.59

0.03

0.20

0.02

0.82

B4 0.04

1.30

0.11

0.49

0.06

0.15

0.02

0.62

B5 0.03

1.67

0.16

0.10

0.06

0.10

0.02

0.60

Hurricane Lili

B2 0.07

1.52

0.09

0.97

0.04

0.33

0.01

1.10

B4 0.04

2.06

0.15

0.75

0.07

0.22

0.08

1.16

B5 0.07

3.47

0.05

0.06

0.03

0.15

0.04

1.39

The ecological investigation addressed the following questions:

 What is the abundance, taxonomic composition and community structure of Ship Shoal’s

meiofaunal community?

 What is the abundance, taxonomic composition and community structure of Ship Shoal’s

macrofaunal community?

 How are Ship Shoal’s meio/macrofaunal communities affected by hysical parameters (e.g.

substrate composition, water depth, currents, position on the shoal), and water chemistry?

 What is the relationship between the dominant members of Ship Shoal’s benthic

communities and the gut contents/fullness of its white and brown shrimp?

 What are the potential impacts of sand mining on the taxonomic composition and

community structure of Ship Shoal communities? Specifically, how rapidly will these

communities recover and how will the taxonomic composition of the recolonized areas

compare with pre-impact conditions?

Benthic Meiofaunal Community

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Relatively few studies of the meiofaunal of shallow continental shelf in the northern

Gulf of Mexico have been performed and no previous research has been conducted

on the meiofaunal of sandy shallow subtidal sediments in Louisiana. Life history

characteristics of interstitial fauna differ from burrowing species in that brooding is

more common and reproductive rates are lower (Swedmark 1964). Meiofauna

appear to be less sensitive to physical disturbance (Schratzberger and Warwick

1998) but are generally slower to recolonize sediment after disturbance events

(Colangelo et al. 1996 compared to burrowing meiofauna (Chandler and Fleeger

1983).

 Findings suggest that Ship Shoal meiofauna are interstitial compared to the

burrowing meiofaunal of surrounding sediments off the shoal

 Evidence that major taxon and species composition differs substantially from

surrounding muddy bottoms

 Lower densities on Ship Shoal than surrounding Louisiana continental shelf.

Lower abundances in sandy sediments is commonly reported.

 Meiofaunal abundance was not correlated with specific physical/chemical

conditions on Ship Shoal.

 Interstitial meiofauna appear to be more resilient than burrowing fauna to

physical disturbance (Schratzberger and Warwick 1998).

 Meiofauna densities are typically highest in the upper 4-6 cm of sediment.

 Meiofauna appear to be more resilient to sublethal physical disturbance because

they are adapted to disturbance caused by weather

 Meiofauna lack dispersing largal stages but re-colonize through the overlying

water which facilitates rapid recovery of areas affected by small-scale

disturbances (Chandler and Fleeger 1983).

 Larger areas of disturbance may be more rapidly colonized by macrofauna larvae

because they are adapted to long-distance dispersal.

 Other studies suggest a slow rate of recovery for meiofauna following sand

mining (Vanaverbeke et al. 2002; Vanaverbeke and Vincx 2008).

 Other studies suggest that macrofaunal recover following sand disturbance may

take many months to years (Palmer et al. 2008).

Benthic Primary Production (BPP)

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 Concluded that benthic micro-algae (BMA) likely serves as the foundation for

unique ecological services provided by Ship Shoal

 High oxygen content on Ship Shoal when surrounding waters were hypoxic or

near hypoxic

 BMA may periodically exceed phytoplankton biomass found in the water-column

 Therefore, BMA rather than phytoplankton, may contribute the most energy

flow through the local Ship Shoal food web.

Benthic Macrofaunal Community

 Results suggest that Ship Shoal represents a faunally distinct habitat type in

transition between in-shore and offshore habitats.

 Species composition on Ship Shoal differed between east and west as well as

north and south areas.

 Species composition was similar to communities associates with Mississippi and

northwest Florida seashore.

 Overall species richness of macrobenthos totaled 118 species. Benthic

assemblages in other nearby areas affected by hypoxia were reported to have

mean species richness of 19 during the same period.

 Dissolved oxygen concentrations on the shoal were relatively high compared to

surrounding areas prone to hypoxia.

 Newell et al. (1998) estimated the rate of recovery for sandy sand environments

after dredging or mining activities is 2 to 3 years or longer depending on the

proportion of sand removed, the proportion of slow-growing species and intensity

of the disturbance.

 The community on Ship Shoal is equilibrated and species rich which suggest

that biological interactions rather than changes in environmental parameters

control the community composition.

 Many species found on Ship Shoal are equilibrium species (K-strategists)

(Newell et al. 1998), indicated by their relatively large body size, slow

reproduction rate and long life-cycles. These species are considered sensitive

species (Gesteira and Dauvin 2000) and will probably be strongly affected by

long-term sand mining.

 A shift in dominance to small, rapid-growing species will reduce the community

biomass which may result in indirect effects at higher trophic levels.

Commercially-Important Species

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 Overall catch of brown shrimp, white shrimp and croaker was very low.

 Effects of sand mining are expected to have less effect on nekton that infauna

because nekton are highly mobile and can avoid the dredging operation.

 Found that Ship Shoal is a nationally important blue crab

spawning/hatching/foraging ground.

Ship Shoal possesses a unique benthic meiofaunal and macrofaunal community due

to its sandy substrate and water depths. Their findings suggest that Ship Shoal

may also provide a refuge from seasonal hypoxia because dissolved oxygen

concentrations over the shoal remained high throughout the spring, summer, and

autumn sampling periods. The overall species richness of macrobenthos on the

shoal totaled 118 species. Baustian (2005) reported much lower species richness (19

species) over a much broader area off coastal Louisiana affected by hypoxia. Benthic

micro-algae, as opposed to phytoplankton, may be the dominant contributor to

primary production on the shoal.

1.5.1.10 USACE Continuing Authorities Program, 1996

Section 204 of WRDA 1992, as amended in WRDA 2007 Section 2037, is a

"continuing authority" that authorizes the Secretary of the Army to plan, design,

and implement certain ecosystem restoration measures, subject to specified cost

sharing, cooperation, and positive Secretarial findings, without additional projectspecific Congressional authorization. Section 204, as amended, authorizes the

beneficial use of sediments in connection with construction, operation, or

maintenance dredging of an authorized Federal water resources project. Section

2037 of WRDA 2007 amends WRDA Section 204 cost sharing responsibilities for

beneficial use of sediment for the protection, restoration, and creation of aquatic

habitats from 75% Federal and 25% non-Federal to 65% Federal and 35% nonFederal.

Section 206 of WRDA 1992 is a continuing authority that authorizes the Secretary

to construct projects for the restoration and protection of aquatic ecosystems

without any connection to an existing Corps project. This authority is directly

related to the restoration of the Terrebonne Basin Barrier Island Chain.

Section 1135 of WRDA 1992 is a continuing authority that authorizes the

Secretary to restore habitat and improve water quality that has been impacted by

existing Corps projects (navigation structures, locks and dams, reservoirs, etc).

Non-governmental, non-profit groups may also sponsor projects under this

authority. This authority could be utilized to modify dredging operations of the

Houma Navigation Canal to benefit the project, if the canal proves to be a viable

source of sediment for use in the restoration efforts.

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In addition to coastal restoration efforts undertaken through the efforts discussed

above, other Federal and State coastal restoration efforts over the years have

resulted in the construction of State projects, Federal projects, and State vegetative

plantings (LDNR, 2003). One of the more significant contributions to the

restoration of coastal wetlands has been a result of the North American Wetlands

Conservation Act, administered by the USFWS. The 1999 and 2001 biennial North

American Wetlands Conservation Act report presented to Congress cites 30,558

acres of restoration and 40,348 acres where ecosystem function has been improved

in coastal Louisiana wetlands.

1.5.1.11 Second Emergency Supplemental Appropriations Act to Meet the

Immediate Needs Arising from the Consequences of Hurricane Katrina,

2005 (Public Law 109-062)

The Second Emergency Supplemental Appropriations Act to Meet the Immediate

Needs Arising from the Consequences of Hurricane Katrina, 2005 (Public Law 109-

062) was adopted by Congress on September 2, 2005. This law provided emergency

supplemental funding to repair damage to flood risk management and hurricane

shore protection projects.

1.5.1.12 Department of Defense, Emergency Supplemental Appropriations to

Address Hurricanes in the Gulf of Mexico, and Pandemic Influenza Act,

2006 (Public Law 109-148)

The Department of Defense, Emergency Supplemental Appropriations to Address

Hurricanes in the Gulf of Mexico, and Pandemic Influenza Act, 2006 (Public Law

109-148), provided funds for the LACPR efforts.

1.5.2 State

1.5.2.1 Louisianas Comprehensive Master Plan for a Sustainable Coast, 2010

The Louisiana Legislature, through Act 8 of the First Extraordinary Session of the

2005 Louisiana Legislature, established the Coastal Protection and Restoration

Authority (CPRA) to develop, implement, make reports on, and provide oversight

for a comprehensive coastal protection master plan and annual coastal protection

plans. Several measures proposed in the Master Plan were incorporated into the

initial array for this LCA TBBSR Study.

1.5.2.2 Gap Analysis

In July 2008, the PDT conducted a gap analysis to determine whether adequate

data and information were available for the Timbalier and Isles Dernieres Barrier

Island reaches to proceed with the Feasibility Report. This gap analysis addressed

the availability of data for hydrology, geology, topographic and bathymetric surveys,

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coastal processes, environmental resources and habitats, threatened and

endangered species, magnetometer and cultural resource surveys, oil and gas

infrastructure, land and water resources, economic resources, project designs, land

use, and navigation.

Because of the emphasis historically placed on barrier island research and barrier

island restoration, a rich body of data and literature exist to support the Terrebonne

Basin Barrier Shoreline Restoration Project. This data came in the form of

planning documents, such as the Louisiana Coastal Area (LCA), Louisiana

Ecosystem Restoration Study, engineering reports, survey reports, Environmental

Assessments, Final Programmatic Environmental Impact Statement (FPEIS)

reports, geological/geotechnical reports and ongoing monitoring programs.

The first large-scale dune building and stabilization project in Louisiana that used

sand fences to stimulate accretion was constructed at Timbalier Island in 1979 and

1980 by Texaco USA. Five years later the Terrebonne Parish Barrier Island

Restoration Project was built at the eastern end of the Isles Dernieres. In 1988 a

preliminary coastal engineering report for the Isles Dernieres Barrier Island

Stabilization Project and an Environmental Assessment was prepared before the

program was terminated by the State. Since the enactment of the Coastal Wetlands

Planning, Protection and Restoration Act (CWPPRA) in 1990, eleven barrier island

restoration projects have been constructed and four have been authorized for

construction.

As part of the engineering and design of these projects, bathymetric and

topographic surveys, hazard and magnetometer surveys, cultural resources

assessments, sand source surveys, and wetland value assessments are typically

conducted. Environmental Assessments are also required before any specific project

can be funded for detailed plans and specifications, and construction. Because of

the rich history of coastal restoration efforts and applied research within the Study

Area, there is an abundance of project-specific data.

In addition to the project specific data, the LCA Science and Technology Program

has developed the Barrier Island Comprehensive Monitoring Program (BICM) that

is providing long-term data on Louisianas barrier islands which will allow for the

evaluation of constructed projects as well as for planning and design of future

barrier island projects. Important components monitored by BICM include

bathymetry, topography, shoreline change, habitats, and storm assessment protocol.

After conducting a thorough review of all relevant project data and information, and

performing the pertinent analyses, the PDT determined that there was sufficient

information available to proceed with the Feasibility Report. Further, it was

determined that no additional data collection or analysis is necessary at this time to

complete the Feasibility Report.

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Specifically, the PDT determined that there are sufficient hydrologic data;

topographic, bathymetric, geophysical, geotechnical, and magnetometer survey

data; coastal processes forcing functions; threatened and endangered species,

wildlife, natural resources, and cultural resources information; and historical

information to complete the Plan Formulation and Alternatives Analyses tasks.

Ship Shoal has been identified as the primary borrow area and it contains sufficient

quantities of beach compatible sand for the Study Area.

1.6 PLANNING PROCESS AND REPORT ORGANIZATION

The Terrebonne Basin Barrier Shoreline Restoration project follows the USACE sixstep planning process specified in Engineering Regulation (ER) 1105-2-100. The

planning process identifies and responds to problems and opportunities associated

with the Federal objective and specified State and local concerns. This integrated

report includes elements of both the planning process and sections specific to the

NEPA review of the project.

The chapter headings and order in this report generally follow the outline of the

required NEPA documentation for an EIS. Chapters of the report relate to the six

steps of the planning process in ER 1105-2-100 as follows:

 Chapter 2: Need For and Objectives of Action

This chapter addresses the first step in the planning process. In the first step

of the planning process, the Study Area problems and opportunities are

defined in addition to the constraints, goals, and objectives. An initial

statement of problems and opportunities was developed for the 2004 LCA

report which reflected the priorities and preferences of the Federal

government, non-Federal sponsor, and other stakeholders. This report

presents an updated problem identification that includes enhanced

understanding of the process and problems of the Study Area.

 Chapter 3: Alternatives

The third chapter of this report addresses the third, fifth, and sixth steps in

the planning process. Step three of the planning process is the formulation of

alternative plans. During this step, the plans developed in the 2004 LCA

report were reevaluated. The fifth step in the planning process addresses

comparisons of the alternative plans with emphasis on the outputs and

affects each alternative. During the sixth step of the planning process, the

selection of the recommended plan is made based upon the comparison of the

alternative plans.

 Chapter 4: Affected Environment

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The fourth chapter of this report addresses the second step of the planning

process which requires an inventory and forecast of resources within the

Study Area. The inventory and forecast of the Study Area provides the

without project condition and is the basis of comparison for the alternatives.

 Chapter 5: Environmental Consequences

The fifth chapter of this report covers the fourth step of the planning process

which evaluates the effects of the proposed alternative plans in terms of

ecosystem benefits. The evaluation criteria are based on the overall goals

and objectives of the LCA program and specific planning objectives and

purposes of the near-term critical restoration projects recommended in the

2005 Chief of Engineers Report.

1.7 USACE CAMPAIGN PLAN

The USACE has developed a Campaign Plan with a mission to provide vital public

engineering services in peace and war to strengthen our Nations security, energize

the economy and reduce risk from disasters. This Campaign plan is shaping

USACE command priorities, focusing transformation initiatives, measuring and

guiding progress, and helping the USACE adapt to the needs of the future.

USACE Campaign Plan Goals and Objectives Summary

 Goal 1: Deliver USACE support to combat, stability and disaster operations

through forward deployed and reach back capabilities.

o Objective 1a: USACE is ready, responsive and reliable in delivering

high performance, all hazard, and contingency mission execution in a

world-wide theater of operations.

o Objective 1b: Prepare Theater Engineer Commands (TEC) to support

Combatant Commanders throughout the spectrum of operations.

o Objective 1c: Establish human resources and family support programs

that promote readiness and quality of life.

o Objective 1d: Institutionalize USACE capabilities in interagency policy

and doctrine.

 Goal 2: Deliver enduring and essential water resource solutions through

collaboration with partners and stakeholders.

o Objective 2a: Deliver integrated, sustainable, water resources

solutions.

o Objective 2b: Implement collaborative approaches to effectively solve

water resource problems.

o Objective 2c: Implement Streamlined and Transparent Regulatory

Processes to Sustain Aquatic Resources.

o Objective 2d: Enable Gulf Coast recovery.

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 Goal 3: Deliver innovative, resilient, sustainable solutions to the Armed

Forces and the Nation.

o Objective 3a: Deliver sustainable infrastructure via consistent and

effective military construction and real estate support to customers.

o Objective 3b: Improve resilience and lifecycle investment in critical

infrastructure.

o Objective 3c: Deliver reliable infrastructure using a risk-informed

asset management strategy.

o Objective 3d: Develop and apply innovative approaches to delivering

quality infrastructure.

 Goal 4: Build and cultivate a competent, disciplined, and resilient team

equipped to deliver high quality solutions.

o Objective 4a: Identify, develop, maintain, and strengthen technical

competencies in selected Communities of Practice (CoP).

o Objective 4b: Communicate strategically and transparently.

o Objective 4c: Standardize business processes.

o Objective 4d: Establish tools and systems to get the right people in the

right jobs, then develop and retain this highly skilled workforce.

This project addresses two points of the USACE Campaign Plan. The second goal of

the USACE Campaign Plan is addressed by this project since it is an element of the

LCA ecosystem restoration plan on the Gulf Coast. This project also addresses the

third goal through the application of the planning process to formulate, analyze,

and evaluate alternative designs in pursuit of a sustainable, environmentally

beneficial, and cost-effective ecosystem restoration design.

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2.0 NEED FOR AND OBJECTIVES OF ACTION

2.1 NATIONAL OBJECTIVES

The USACE planning process is based on the economic and environmental

Principals and Guidelines (P&G) promulgated in 1983. The P&G provide for

development of reasonable plans that are responsive to National, State, and local

concerns. Planning project benefits are quantified in this process as National

Economic Development (NED) output, National Ecosystem Restoration (NER)

output, or a combination of NED/NER output.

Ecosystem restoration is one of the primary goals of the USACE Civil Works

Program. The USACE objective in ecosystem restoration planning is to contribute

to NER. NER contributions include increases in the net quantity and/or quality of

desired ecosystem resources. NER measurements are changes in ecological

resource quality as a function of improvement in habitat quality and/or quantity.

The units are expressed quantitatively in physical units or indexes that are not

based on monetary units. Net changes are measured in the Study Area and in the

rest of the Nation. Single-purpose ecosystem restoration plans shall be formulated

and evaluated in terms of their net contributions to increases in NER output.

Multipurpose plans that include ecosystem restoration shall contribute to both NED

outputs and NER outputs. For multipurpose projects, a plan that trades off NED

and NER benefits to maximize the sum of net contributions to NED and NER is

usually recommended. However, under Title VII of WRDA 2007, any project or

separable project element under LCA may be justified by the environmental

benefits alone and economic justification is not required if the Secretary determines

that the project or activity is cost-effective.

Louisiana contains one of the largest expanses of coastal wetlands in the contiguous

United States and accounts for 90 percent of the total coastal marsh loss occurring

in the Nation. The LCA TBBSR Study Area is an essential ecosystem since it

includes wetland habitats, essential fish habitat, and has high fish and wildlife

values. The barrier islands protect the interior coastal wetlands, which also have

high fish and wildlife value as well as great economic value as commercial and

recreational fisheries. These ecosystems provide habitat for migratory birds,

wildlife, finfish, shellfish, and other aquatic organisms including threatened or

endangered species. The restoration of these barrier islands would protect these

national assets from further degradation.

2.2 PUBLIC CONCERNS

Public input was received during several scoping meetings as well as meetings with

various stakeholders. Many people expressed that the timeline for the Study

needed to be advanced due to the urgency of the need in the Study Area. Others

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worried about access to and protection of the restored areas. The impact on

landowners and users of the Study Areas was discussed as well as the impact on

threatened and endangered species. Comments were received concerning

construction methods and borrow sources. Effects to the tidal prism were also

mentioned.

Details of the public comments about the Study are in Chapter 6 of this document.

2.3 PROBLEMS, NEEDS, AND OPPORTUNITIES

2.3.1 General Problem Statement

The overarching problem in the Study Area is a lack of sustainability of the coastal

ecosystem, primarily due to coastal land loss. Natural processes and human

actions, such as the construction of oil field canals and the containment of

waterways, have threatened the long-term viability of the Study Area. These

processes and activities have all caused significant adverse impacts to the

Terrebonne Basin barrier island shoreline, resulting in extensive barrier island

habitat loss and ecosystem degradation. (USACE, 2004a).

Specific problems in the LCA TBBSR Study Area are:

 Land loss due to erosion threatens the geomorphic and hydrologic barrier

systems

 Longshore sediments are significantly reduced, limiting the ecosystems

ability to be self-sustaining.

 Loss of barrier island/headland ecosystem habitat

 Freshwater wetlands are impacted by increased salinity

The following sections discuss general ecosystem problems identified in the Study

Area.

2.3.2 Subsidence

Land elevations decrease due to subsidence from compaction and consolidation of

sediments, faulting, groundwater depletion, and sub-surface fluid extraction. Land

elevations increase due to sediment accretion from riverine and littoral sources and

organic deposition from vegetation. Vertical accretion in the majority of the Study

Area is insufficient to offset subsidence, decreasing land elevations. Based on

NOAAs (http://tidesandcurrents.noaa.gov) current mean sea level (MSL) trend at

Grand Isle, LA of 9.24 mm/yr and global MSL rise of 1.7 mm/yr (USACE, 2009b),

the subsidence rate in the LCA TBBSR Study Area is estimated at 7.54 mm/yr.

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2.3.2.1 Sea Level Change

2.3.2.1.1 Eustatic Sea Level Change

Eustatic sea level change is the global change of the oceanic water level. According

to the Intergovernmental Panel on Climate Change (IPCC, 2007), the global mean

sea level (MSL) rose at an average rate of about 1.7 mm/yr during the twentieth

century. Recent climate research has documented global warming during the

twentieth century, and has predicted either continued or accelerated global

warming for the twenty-first century and possibly beyond (IPCC, 2007). There are

numerous projections of future eustatic sea level rates (NRC, 1987). The NRC

recommends that three eustatic sea level accelerations be evaluated for engineering

projects, namely NRC curves I, II, and III. The latest Corps guidance (USACE,

2009b) recommends the use of NRC curves I and III for projecting the intermediate

and high eustatic sea level rates (Figure 2-1). The corresponding eustatic sea level

changes between 2006 and 2062 are estimated at 222 mm for the intermediate rate

and 635 mm for the high rate.

Year

Sea Level Rise (feet)

2000 2010 2020 2030 2040 2050 2060 2070 0

0.5

1

1.5

2

2.5

3

3.5

4

Low/Historic

Intermediate (NRC Curve I)

High (NRC Curve III)

Estimated Relative (Eustatic + Subsidence)

Sea Level Rise Since 2006

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Figure 2-1: Estimated Relative Sea Level Rise since 2006

2.3.2.1.2 Relative Sea Level Change

Relative sea level change is the term applied to the effects of the combination of

eustatic sea level change and the change in land elevation. The combination of

subsidence and eustatic sea level rise is likely to cause the landward movement of

marine conditions into estuaries, coastal wetlands, and fringing uplands (Day and

Templet, 1989; Reid and Trexler, 1992).

According to NOAA (http://tidesandcurrents.noaa.gov), the relative mean sea level

trend at Grand Isle, LA is 9.24 mm/yr with a 95% confidence interval of +/- 0.59

mm/yr. Using the USACE (2009b) projections of future changes in mean sea level,

the estimated relative sea level changes in the LCA TBBSR Study Area between

2006 and 2062 are 517 mm, 644 mm, and 1058 mm, for the low/historic,

intermediate and high rates, respectively.

2.3.2.1.3 Retreating and Eroding Barrier Islands

The barrier islands in the Study Area are the remains of an abandoned Mississippi

River Delta; and their degradation is the result of the anthropogenic activities and

natural deltaic processes. Barrier islands act as a buffer to reduce the effects of

ocean waves and currents on associated estuaries and wetlands. Louisiana's barrier

islands are eroding at a rate of up to 20 meters per year, and according to recent

United States Geological Survey (USGS) estimates, several of these islands will

disappear by the end of the century (LACPR, 2009). The disappearance of the

barrier islands exposes coastal wetlands to the full force and effects of wave action,

saltwater intrusion, storm surge, and tidal currents, accelerating wetlands

deterioration.

2.3.2.1.4 Lack of Sediment

As discussed in the previous section, the barrier islands in the Study Area are the

remnants of the abandoned Mississippi River Delta. The islands currently exist in

a sediment-starved environment typical of the erosional barrier arc stage of the

deltaic cycle. The lack of sediment is also attributed to the islands being cut off from

potential sediment sources by the Mississippi River by flood protection levees and

other navigation projects such as the Belle Pass jetties to the east of the Study

Area.

2.3.2.1.5 Shoreline Erosion

The soil along natural ridges and barrier islands is susceptible to wind-induced

erosion. Storm events can directly and indirectly contribute to coastal land loss

through a variety of ways: erosion from increased wave energies, removal and/or

scouring of vegetation from storm surges, and saltwater intrusion into estuaries and

interior wetlands carried by storm surges. These destructive processes can result in

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the loss and degradation of large areas of coastal habitats in a relatively short

period of time (days and weeks versus years). When these soils are eroded away,

organic marsh soils are directly exposed to open water wave attack. Tropical storm

events and natural tidal processes are other natural causes of shoreline erosion.

Combining these natural causes with man-made activities (navigation/access

channels) further subjects inland areas to more dramatic tidal forces and wave

action, increasing erosion.

2.3.2.1.6 Modification of Natural Hydrology

Navigation channels, control of the Mississippi River and its distributaries, and

canals dredged for oil and gas extraction have dramatically altered the hydrology of

the Study Area. By altering salinity gradients and patterns of water and sediment

flow through marshes, canal dredging not only directly changed land to open water,

but also indirectly changed the hydrological processes essential to a healthy coastal

ecosystem.

Man-made canals and channels have also affected natural hydrology, affecting the

sediment and nutrient transport along the islands. Dredged material banks also

block the movement of sediment re-suspended during storms, which plays a major

role in sustaining land elevations (Reed et al., 1997). Back barrier canals also act

as sediment sinks, hindering the natural overwash and migration process of the

islands.

2.3.2.1.7 Saltwater Intrusion

Saltwater intrusion changes the salinity gradient, which results in habitat changes.

Salinity levels exist along a gradient, which declines as the saltwater moves inland

from the GOM. A distinct zonation of plant communities, or vegetative habitat

types, differing in salinity tolerance exists along that gradient, with the species

diversity of those zones increasing from salt to fresh environments. Changes to the

salinity gradient are caused by a number of factors, including: the construction of

levees, man-made channels and canals, and degraded barrier islands. Tropical

storm events can introduce saltwater into fresher areas, damaging large amounts of

habitat in a short period of time.

2.3.2.2 Habitat Changes and Land Loss

2.3.2.2.1 Wetland Loss

Perhaps the most serious and complex problem in the Study Area is the rate of land

and habitat loss. As noted above, relative sea rise, tropical storms, shoreline

erosion, modification of natural hydrology, and other factors contribute to loss of the

barrier islands in the Study Area. The sustainability of the coastal ecosystems is

threatened by the inability of the barrier islands to maintain geomorphologic

functionality.

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2.3.2.2.2 Herbivory

Both the native muskrat (Ondatra zibethicus) and the introduced nutria (Myocastor

coypus, native to South America) are major contributors to wetland losses in coastal

Louisiana (LACPR, 2009). The nutria have experienced a rapid expansion of their

population since their introduction into the Louisiana coastal wetlands in the

1930s. The grazing and foraging for plant roots by both species have led to eatouts, which often result in significant local impacts to area marshes. Although

these eat-outs may recover under some conditions, tropical storm impacts on an eatout area may directly convert these marshes to permanent open water conditions

(USGS, 2000). Often, the resulting landscape is dominated by aggressive nonnative and/or unpalatable native plants, and a weakening of the marsh structural

integrity (Baroch, et al., 2002).

2.3.3 Needs

Critical needs in the Study Area include:

 Restore and/or preserve critical and essential geomorphic structures

(beach, dune, ridge, and marsh) of the Terrebonne Basin barrier system.

 Reduce and/or prevent future land loss, habitat loss, and fragmentation of

the land features.

 Protect vital local, regional, and national socio-economic resources.

 Protect the back barrier estuarine environments from the high energy

marine processes and associated salinities of the Gulf of Mexico.

 Near-term restoration should be synergistic with future restoration by

maintaining or restoring the integrity of Louisianas coastline, upon which

all future coastal restoration is dependent.

 Design and operate restoration features that support the development of

large-scale, long-range comprehensive coastal restoration.

The natural processes of subsidence and erosion have combined with human-caused

effects leading to significant shoreline retreat and land loss along the Terrebonne

Basin barrier island chain. Construction of levees along the Mississippi River to

prevent flooding has effectively stopped the nourishment of the wetlands with

riverine nutrients and sediments. Confinement of the Mississippi has also caused

its bedload to be deposited in progressively deeper waters of the GOM. In addition,

the sediment load of the river has declined by over 50% due to flood control works

and bank stabilization upstream. The latter two factors have prevented the

Mississippi River sediments from nourishing the barrier islands (USACE, 2004a).

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The Isles Dernieres and Timbalier barrier islands are expected to be impacted by

multiple tropical weather events over the next several decades. Each storm poses

the risk of breaching the existing islands. As a result, these barrier islands will

continue to degrade and migrate landward as an increasingly fragmented chain of

smaller barrier islands. The fragmentation of the barrier islands will progressively

increase the risk of a single storm event causing widespread fundamental changes

in the hydrodynamics and ecological function of the interior bay system. Based on

historical trends, a direct hurricane or tropical storm impact can be expected on a

frequent basis.

Complete opening of the bays to the unabated effects of storms will increase the

volume of open water and fetch within these bays, decreasing their ecologic value.

Ecologic changes will occur and storm surges will increase, requiring greater levels

of flood risk reduction infrastructure in populated areas. As the islands continue to

fragment and migrate northward allowing intrusion of the GOM, restoration will

become progressively more expensive and difficult to implement. The effects of

increased wave and storm energy will increase stress on, and contribute to a

reduction in the vigor and aerial extent of, the remaining wetlands that now serve

as a buffer affording protection against storms to the developed areas located north

of the Study Area (USACE, 2008).

2.3.4 Study Area Opportunities

To address the overarching Study Area problem of sustainability, a combination of

restoration strategies applied in a systematic manner to restore the ecosystem is

needed. Examples of restoration strategies are vegetative planting, the use of

dredged material for site-specific restoration (beach and marsh fill), hydrologic

modification, restoration/preservation of critical geomorphic structures, and where

appropriate hard-structural solutions (breakwaters, revetments, etc.). These and

other restoration strategies are represented by the various management measures

evaluated.

Opportunities for ecosystem restoration include:

 Increase longevity of the barrier island geomorphic function

 Improve the habitat value of the barrier islands

 Increase sediment into the longshore transport process

 Restore diversity of the barrier island habitats

Many of the above opportunities can be utilized in combination with planned or

existing projects to produce synergistic effects while minimizing disruptions to the

surrounding ecosystem and economy.

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2.4 PLANNING OBJECTIVES

For the LCA 2004 Study, two tiers of planning objectives were established 

hydrogeomorphic and ecosystem objectives. The hydrogeomorphic objectives were:

 Establish dynamic salinity gradients that reflect natural cycles of

freshwater availability and marine forcing.

 Increase sediment input from sources outside estuarine basins, and

manage existing wetlands and rebuild marsh substrate.

 Maintain or establish natural landscape features and hydrologic processes

that are critical to sustainable ecosystem structure and function.

The ecosystem objectives were:

 Sustain productive and diverse fish and wildlife habitats.

 Reduce nutrient delivery to the Continental shelf by routing Mississippi

river waters through estuarine basins while minimizing potential adverse

effects.

The LCA TBBSR Study Area objectives are a localized and project specific

delineation of the LCA objectives. The Terrebonne Basin barrier shoreline is a

unique ecosystem that helps to maintain the integrity of the gulf shoreline and

protects the interior coast from further degradation. Aside from supporting coastal

habitats, the coastal barrier chains in Louisiana are the first line of defense for

protecting wetlands, inland bays, and mainland regions from direct effects of wind,

waves, and storms. The barrier systems serve multiple defensive purposes to:

 Reduce coastal flooding during periods of storm surge;

 Prevent direct ocean wave attack, which would accelerate rates of erosion

and degradation of marshes and other wetlands; and

 Help maintain gradients between saline and freshwater, thereby

preserving estuarine systems.

Based on the function of these barrier islands and problems identified for the

Terrebonne islands during this study, the following planning objectives were

developed to assist the development and evaluation of alternative plans.

 Provide an expanded footprint of minimized barrier island section to

provide the geomorphic form and ecologic function of the Terrebonne

Basin barrier island, reducing volume loss within the LCA TBBSR Study

Area below the historic average (1880 through 2005)

 Restore and improve various barrier island habitats that provide essential

habitats for fish, migratory birds, and other terrestrial and aquatic

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species, mimicking, as closely as possible, conditions which would occur

naturally in the area for the 50 year period of analysis.

 Increase sediment input to supplement longshore sediment transport

processes along the gulf shoreline by mechanically introducing compatible

sediment, and increasing the ability of the restored area to continue to

function and provide habitat for the 50 year period of analysis with

minimum continuing intervention.

2.5 PLANNING CONSTRAINTS

Planning constraints relevant to the Study include natural resources limitations

such as lack of suitable sediments for restoration; environmental impacts of human

activities in the Study Area; infrastructure and cultural resources that must be

avoided or relocated; and limitations in the characterization and simulation of

environmental processes that determine the effects of alternatives plans. Winds

and waves caused by storm events have been known to move artifacts and pipelines

on the seafloor of the Gulf of Mexico. Additionally, barrier shoreline systems are

dynamic. Each hurricane and winter season will impact the shoreline to varying

degrees. Breaches created during a hurricane are often healed through the natural

sand transport processes. However, lack of sediment in the Terrebonne barrier

system has limited the natural ability of these breaches to close. Throughout the

study, the teams analyses attempted to incorporate data relating to these changes.

However, the dynamic nature of the shoreline makes it more difficult to accurately

simulate and predict the affects of the various alternatives.

2.6 FUTURE WITHOUT PROJECT

The Study, located in LCA Subprovince 3, provides for the restoration of the

Timbalier and Isles Dernieres barrier island reaches located in Terrebonne Parish

and Lafourche Parish, Louisiana. The Study Area is shown on Figure 2-2.

Isles Dernieres Reach

The Isles Dernieres Reach represents a barrier island arc approximately 22 miles

long in Terrebonne Parish and extends from Caillou Bay east to Cat Island Pass.

Raccoon Island, Whiskey Island, Trinity Island, East Island, and Wine Island, the

primary islands that comprise the Isles Dernieres barrier island reach, are backed

by Bay Blanc, Bay Round, Caillou Bay, and Terrebonne Bay, and bordered by the

Gulf of Mexico (GOM) on the seaward side. The islands range from approximately

0.1 to 1.2 miles wide and are generally composed of a thin sand cap over a thick

mud platform. Elevations are generally low and the islands are frequently

overwashed (USACE, 2004c).

The Isles Dernieres have been and continue to be an important commercial and

recreational resource for Louisiana and the nation for more than 150 years. The

islands support habitats that are critical to the States commercial fishing industry.

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Furthermore, the mineral-rich subsurface below Terrebonne Bay, Lake Pelto, and

Timbalier Bay has supported a high concentration of oil and gas wells.

Timbalier Reach

The Timbalier Reach is comprised of Timbalier Island and East Timbalier Island.

The two islands are on the western edge of the Lafourche barrier shoreline and are

located about 60 miles southwest of New Orleans, Louisiana (Figure 2-2). This

barrier island shoreline is approximately 20 miles long and backed by Terrebonne

and Timbalier Bay to the north and delimited by Raccoon Pass to the east and Cat

Island Pass to the west. The islands range from 0.1 to 0.6 miles wide and have low

elevations. The Timbalier Islands support onshore and offshore oil and gas

development and production. Oil and gas production facilities are prevalent along

East Timbalier Island, while only a few scattered facilities are present along

Timbalier Island. Oil and gas canals are present on both islands (USACE, 2004c).

The Timbalier Islands are very dynamic island systems that form the eastern end of

the Study Area and are migrating both landward and laterally. The Timbalier

Islands are comprised of the Western and Eastern section of Timbalier and East

Timbalier Island. Over the last century, Timbalier Island lost most of its area,

shrinking from 3,580 acres to 1,349 acres; most of the loss occurred on the bayside.

From 1978 to 1988, the island lost an average of 63 acres/yr as result of opposite

rates of migration of Gulf and bayside shorelines, that is, the bayside shoreline

migrated seaward while the Gulf shoreline migrated landward.

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Figure 2-2. Terrebonne Basin Barrier Shoreline Restoration Study Area

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Raccoon Island

Description

Raccoon Island is approximately 2.6 miles long (USDA, 2007b) and is located at the

western end of Isles Dernieres. It is the largest shorebird rookery in the Isles

Dernieres. Raccoon Island is characterized by sandy beach with well-vegetated

washover terraces backed by thick groves of black mangrove and salt marsh. The

recurved spit at the west end is low and dominated by washover flats.

Figure 2-3. Aerial Photograph of Raccoon Island in 2008 (Prior to

construction of the TE-49 back barrier marsh)

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Figure 2-4. Congregation of seabirds on a breakwater on Raccoon Island

Figure 2-5. Aerial view of existing breakwaters on Raccoon Island

Figure 2-6. Northerly view of existing breakwaters on Raccoon Island

Proposed Projects

There are two existing CWPPRA projects that were accounted for in the analysis of

Raccoon Island: TE-29 and TE-48. The TE-29 project, which was completed in July

1997, included the construction of eight segmented breakwaters along the eastern

end of the island. The TE-48 project consists of two phases. Phase A, which

included the construction of eight additional segmented breakwaters and a terminal

groin, was completed in September of 2005. The terminal groin, which was

constructed on the eastern end of the island, was intended to prevent longshore

currents from scouring accumulated sediment behind the breakwater field. Phase B,

which is currently in the pre-construction phase, will include the creation of a 53-

acre marsh along the backside of the island.

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An additional CIAP project, which proposed 16 additional breakwaters on Raccoon

Island, was considered, but was not included in the analysis because the plans are

preliminary and the State is pursuing the use of these CIAP funds as cost share for

the LCA project. No additional projects, including CWPPRA or CIAP projects have

been proposed for Whiskey Island.

Landloss

The average historic shoreline change between 1887 and 2002 was 27.4 ft/yr with a

range of 28.9 to -24.9 ft/yr. The average short-term shoreline change between 1988

and 2002 was -60.5fy/yr with a range of -144.5 to -8.6 ft/yr (USACE, 2004c). The

average long-term shoreline change rate between 1956 and 1988 developed from the

atlas of shoreline changes on Louisiana (William et al., 1992) was -28.6 ft/yr.

Since 1978, Raccoon Island rapidly decreased in area from 368.2 to 200.2 acres

between 1978 and 1988. During this time period, multiple hurricane impacts

occurred in 1979 (Bob and Claudette) and 1985 (Danny, Elena, and Juan). From

1988 to 1992, Raccoon Island further decreased in area from 200.2 acres to 167.8

acres. With the impact of 1992s Hurricane Andrew, the area of Raccoon Island

continued to decrease even further to 112.8 acres. By 1993, Raccoon Island had

further reduced in area to 99.2 acres. A Federal Emergency Management Agency

(FEMA) restoration project constructed in 1994 increased the size of Raccoon Island

to 127.2 acres by 1996. An additional segmented breakwater project further

increased the area of Raccoon Island to 145.5 acres by 2002. While the hurricane

impacts in 2005 (Katrina and Rita) caused erosion, the breakwaters continued to

benefit the island (USACE, 2004c). Though an increase in acreage was observed in

2006 (215 acres), the effects of Hurricanes Gustav and Ike reduced Raccoon Island

to 121 acres by the winter of 2008 (Barras, 2009).

For this study, the island dimensions and habitat composition of Raccoon Island

were determined by applying vertical adjustments (subsidence and sea level rise)

and horizontal adjustments (background erosion and overwash) to the existing

island footprint for each target year (see Appendix L). The footprint includes 73

acres of existing mangrove stands and the 53-acre marsh component that was

constructed as part of TE-48. The horizontal adjustment accounted for the impacts

of the existing breakwaters (TE-29 and TE-48). The resulting habitat acreages are

summarized in Table 2-1.

Table 2-1. Habitat Acres and Year of Disappearance for Raccoon Island

FWOP

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Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

Raccoon

Dune 0 0 0 0 0 0 0 0 NA

Supratidal 51 51 30 10 3 0 0 0 TY30

Intertidal 188 184 161 137 76 55 0 0 TY40

aYOD: Year of Disappearance

At TY0, the dimensions of Raccoon Island (i.e. height, width, and depth of each

habitat type) are not sufficient to provide geomorphologic form and ecologic function

as defined in Section 3.3.2.2.1. As seen in Table 2-1, the island lacks dune habitat

(i.e. subaerial acreage greater than +5ft NAVD) and the 51 acres of supratidal

habitat is expected to disappear by TY30. By TY40, the 188 acres of intertidal

habitat will be gone, including the 73 acres of existing mangrove stands that were

observed on the island during the November 2008 and July 2009 site visits.

Therefore, if no additional actions are taken, the year of disappearance (YOD) for

the entire island is TY40.

Future Ecosystem Losses Without Project

If no action is taken to restore Raccoon Island, the following significant

environmental resources will be lost that have institutional, public, and technical

importance.

 Westernmost end of the Isles Dernieres Barrier Island Refuge

 Second largest nesting colony of brown pelicans in Louisiana (Linscombe,

1993)

 Largest species diversity of aquatic birds of any single island in Louisiana

and perhaps North America (Linscombe, 1993)

 Critical habitat for piping plover

 188 acres of Essential Fish Habitat (EFH) and highly productive marsh

 51 acres of supratidal habitat utilized by the brown pelican as a rookery and

by migrating birds as resting areas

 Storm surge protection for western Terrebonne Parish

The following photographs provide an overview of the existing habitats found on

Raccoon Island.

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Figure 2.7. Brown Pelican rookery on Raccoon Island

Figure 2.8. Representative view of the mangrove habitat on Raccoon

Island during nesting season

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Whiskey Island

Description

Whiskey Island is located near the middle of five islands in the Isles Dernieres

barrier island reach. It is approximately 4.6 miles long (USDA, 2007b) and located

approximately 17.5 miles southwest from Cocodrie, Louisiana in Terrebonne Parish.

Figure 2.9. Aerial Photograph of Whiskey Island in 2008 (Prior to the

construction of TE-50 back barrier marsh))

Proposed Projects

CWPPRA project TE-50 created approximately 316 acres of intertidal back-barrier

marsh between the two existing mangrove stands. The project was completed

during the course of this Study (October 2009) and was therefore accounted for in

the analysis.

An additional CWPPRA project, TE-47, was considered but was not accounted for in

the analysis of Whiskey Island. The proposed project would restore the west flank

of Whiskey Island, creating a net benefit of 195 acres. Although the Engineering

and Design phase has been completed, the project was not approved for

construction. No additional projects, including CIAP projects have been proposed

for Whiskey Island.

Landloss

The average historic shoreline change rate between 1887 and 2002 was -56.0 ft/yr

with a range of -77.5/- 45.7 ft/yr. The average short-term shoreline change rate was

-86.0 ft between 1988 and 2002 with a range of -139.4/-48.4 ft/yr (USACE, 2004c).

The average long-term shoreline change rate between 1956 and 1988 developed

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from the atlas of shoreline changes on Louisiana (William et al., 1992) was -42.7

ft/yr.

Prior to restoration, the morphology of Whiskey Island was dominated by washover

flats and isolated washover terraces. The CWPRRA restoration project (TE-27) at

Whiskey Island created an artificial dune +4 to +6 ft in elevation, which was 2 to 3

ft above the natural pre-restoration surface. As seen throughout the Isles Dernieres,

Whiskey Island is historically erosional and decreasing in area. Between 1978 and

1988, Whiskey Island decreased in area from 904.4 acres to 564.2 acres. The

hurricanes of 1979 and 1985 were contributing factors to the decrease in area. By

1992, Whiskey Island had decreased to 505.6 acres. During the 1992 hurricane

season, Hurricane Andrew impacted this area dramatically, reducing Whiskey

Island to 440.8 acres. By 1993 it had further decreased in area to 428.4 acres. Post

storm recovery processes increased the area of Whiskey Island to 474.8 acres by

1996. Construction of the Whiskey Island project (TE-27) began in February 1998

and was completed in August 1998. By 2002, the area of Whiskey Island had

increased to 642.8 acres, a 36% increase in area. While the hurricanes in 2005

impacted the island, overwash processes and longshore sediment transport from

Trinity and East Islands benefited Whiskey Island (USACE, 2004c). The effects of

Hurricanes Gustav and Ike decreased the area of Whiskey Island to 509 acres.

For this study, the island dimensions and habitat composition of Whiskey Island

were determined by applying vertical adjustments (subsidence and sea level rise)

and horizontal adjustments (background erosion and overwash) to the existing

island footprint for each target year (see Appendix L). The footprint includes the

316-acre marsh component that was constructed as part of TE-50. Table 2-2

summarizes the habitat acreages computed for Whiskey Island for the period of

analysis.

Table 2-2. Habitat Acres and Year of Disappearance for Whiskey Island

FWOP

Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

Whiskey

Dune 0 0 0 0 0 0 0 0 NA

Supratidal 377 367 40 4 0 0 0 0 TY17

Intertidal 443 436 692 616 468 375 0 0 TY31

aYOD: Year of Disappearance

At TY0, the dimensions of Whiskey Island (i.e. height, width, and depth of each

habitat type) are not sufficient to provide geomorphologic form and ecologic function

as defined in Section 3.3.2.2. As seen in Table 2-2, the island lacks dune habitat

(i.e. subaerial acreage greater than +5ft NAVD) and the 377 acres of supratidal

habitat is expected to disappear by TY17. By TY31, the 443 acres of intertidal

habitat will be gone, including the 286 acres of existing mangrove stands that were

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observed on the island during the November 2008 and July 2009 site visits.

Therefore, if no additional actions are taken, the year of disappearance (YOD) for

the entire island is TY31.

Impacts of Landloss

If no action is taken to restore Whiskey Island, significant environmental resources

will be lost that have institutional, public, and technical importance.

 443 acres of Essential Fish Habitat (EFH)

 Critical habitat for piping plover

 377 acres of supratidal habitat

 Storm surge protection for Terrebonne Parish

 Protection of oil and gas infrastructure

The following are representative photographs of habitats and features found on

Whiskey Island.

Figure 2-10. Oil and gas facility located east of Whiskey Island

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Figure 2-11. Back barrier marsh and mangrove habitat found on Whiskey

Island

Figure 2-12. Oyster reefs located behind Whiskey Island

Trinity Island

Description

Trinity Island, the largest island of the Isles Dernieres, is approximately 5.2 miles

long (USDA, 2007b) and lies immediately to the east of Whiskey Island. The

morphology includes low dune terraces, with isolated dunes of up to 3 to 4 ft in

elevation. Overwash is more frequent at the west and east ends of the island where

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elevations decrease. It is a remnant of the original mainland marsh and wellvegetated by black mangroves and salt marsh species. Trinity Island is historically

eroding. Between 1978 and 1988, Trinity Island decreased in area from 1,317.1

acres to 894.6 acres. This was a time period of multiple hurricanes in occurring in

1979 and 1985. By 1992, Trinity Island further decreased to 796.5 acres. During the

1992 hurricane season, Hurricane Andrew impacted this area, reducing Trinity

Island to 678.5 acres and by 1993, the island decreased further to 651.4 acres. By

1996, the area of Trinity Island continued to decrease to 617.4 acres. Trinity Island

increased in area from 617.4 to 710.1 in 2002 as a result of a restoration project

constructed on the western end of the islands (USACE, 2004c). Though the impacts

of Hurricanes Katrina and Rita were offset by the New Cut Project in 2006

(increasing Trinity Island to 764 acres), the effects of Hurricanes Gustav and Ike

decreased the total area of the island to 509 acres by 2008 (Barras, 2009).

Figure 2-13. Aerial Photograph of Trinity Island in 2008

Proposed Projects

A beach and back barrier marsh restoration project for Trinity and East Island was

presented at the CWPPRA Task Force Meeting in January 2006, but was not

selected for CIAP funding. Therefore, the project was not included in the Trinity

Island analysis. No additional projects, including CWPPRA or CIAP projects have

been proposed for Trinity Island at this time.

Landloss

The average historic shoreline change rate between 1887 and 2002 was -38.4 ft/yr

with a range of -47.9/-34.3 ft/yr. The 19882002 average short-term change rate was

-62.5 ft/yr with a range of -107.3/-41.1 ft/yr. The acceleration between the long-term

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and short-term shoreline change rates is linked to the major hurricane impacts of

1992 and 2002 (USACE, 2004c). The average long-term shoreline change rate

between 1956 and 1988 developed from the atlas of shoreline changes on Louisiana

(William et al., 1992) was -39.7 ft/yr.

For this study, the island dimensions and habitat composition of Trinity Island

were determined by applying vertical adjustments (subsidence and sea level rise)

and horizontal adjustments (background erosion and overwash) to the existing

island footprint for each target year (see Appendix L). Table 2-3 summarizes the

habitat acreages computed for Trinity Island for the period of analysis.

Table 2-3. Habitat Acres and Year of Disappearance for Trinity Island

FWOP

Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

Trinity

Dune 39 32 4 3 0 0 0 0 TY20

Supratidal 232 206 137 52 3 1 0 0 TY33

Intertidal 311 326 327 245 72 19 0 0 TY40

aYOD: Year of Disappearance

At TY0, the dimensions of Trinity Island (i.e. height, width, and depth of each

habitat type) are not sufficient to provide geomorphologic form and ecologic function

as defined in Section 3.3.2.2.1. As seen in Table 2-3, the island has 39 acres dune

habitat, 232 acres of supratidal habitat, and 311 acres of intertidal habitat. The

dune habitat is expected to disappear by TY20 and most of the supratidal habitat

will disappear by TY20. By TY40, the 311 acres of intertidal habitat will be gone.

Therefore, if no additional actions are taken, the year of disappearance (YOD) for

the entire island is TY40.

Future Ecosystem Losses Without Project

If no action is taken to restore Trinity Island, significant environmental resources

will be lost that have institutional, public, and technical importance.

 311 acres of Essential Fish Habitat (EFH)

 Critical habitat for piping plover

 232 acres of supratidal habitat

 Storm surge protection for Terrebonne Parish

 Protection of oil and gas infrastructure

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Figure 2-14. Northerly view of and oil and gas facility protected by Trinity

Island

Figure 2-15. Southeasterly view of Trinity Island

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Figure 2-16. Typical view of the mangrove community on Trinity Island

Figure 2-17. Remnant of a fishing camp on Trinity Island

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Figure 2-18. One of the many raccoons that inhabit Trinity Island

Figure 2-19. Statue of Mary placed on Trinity Island by the Whiskey Pass

Redfish Association

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Figure 2-20. One of the many shorebirds that utilize Trinity Island

East Island

Description

East Island is approximately 3.1 miles long (USDA, 2007b) and is the easternmost

island of the Isles Dernieres. It is characterized by low dunes and washover

terraces, with elevations ranging from +3 to +5 North American Vertical Datum

1988 (NAVD 88).

Figure 2-21. Aerial Photograph of East Island In 2008

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Proposed Projects

A beach and back barrier marsh restoration project for Trinity and East Island was

presented at the CWPPRA PPL 16 in January 2006, but was not selected for CIAP

funding. Therefore, the project was not included in the East Island analysis. No

additional projects, including CWPPRA or CIAP projects have been proposed for

East Island at this time.

Landloss

Prior to restoration, East Island was rapidly eroding and decreasing in area since

1887. In 1978, East Island was 368.2 acres in area and by 1988 it had decreased in

size to 202.2 acres. The average historic shoreline change between 1887 and 2002

was -17.0 ft/yr with a range of - 34.6/-5.1 ft/yr. Short-term, between 1988 and 2002,

the average shoreline erosion rates accelerated to -38.6 ft/yr with a range of -64.0/-

14.0 ft/yr. During this period of time multiple hurricane impacts occurred in 1979

and in 1985. The 1985 impacts prompted island restoration efforts by way of the

LCA TBBSR Study (USACE, 2004c). The average long-term shoreline change rate

between 1956 and 1988 developed from the atlas of shoreline changes on Louisiana

(William et al., 1992) was -39.7 ft/yr.

By 1992, East Island had continued to lose land and measured 173.4 acres in size.

After Hurricane Andrew made landfall in 1992, East Island was further reduced to

93.4 acres, and this continued into 1993 when East Island reached 88.5 acres in

size. Following Hurricane Andrew, FEMA did an emergency restoration project east

of the former Terrebonne Parish restoration site, resulting in East Island enlarging

from 88.5 acres in 1993 to 193.1 acres in 1996. The CWPPRA East Island

restoration was completed in 1998, and the area of the island increased from 193.1

acres to 380.4 acres by 2002 (USACE, 2004c). By 2008 East Island decreased to

approximately 300 acres due to the hurricane impacts in 2005 and 2008.

For this study, the island dimensions and habitat composition of East Island were

determined by applying vertical adjustments (subsidence and sea level rise) and

horizontal adjustments (background erosion and overwash) to the existing island

footprint for each target year (see Appendix L). Table 2-4 summarizes the habitat

acreages computed for East Island for the period of analysis.

Table 2-4. Habitat Acres and Year of Disappearance for East Island FWOP

Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

East

Dune 35 23 5 4 0 0 0 0 TY20

Supratidal 178 176 86 46 6 0 0 0 TY29

Intertidal 71 59 110 101 58 16 0 0 TY40

aYOD: Year of Disappearance

At TY0, the dimensions of East Island (i.e. height, width, and depth of each habitat

type) are not sufficient to provide geomorphologic form and ecologic function as

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defined in Section 3.3.2.2.1. As seen in Table 2-4, the island has 35 acres dune

habitat, 178 acres of supratidal habitat, and 71 acres of intertidal habitat. The

dune habitat is expected to disappear by TY20 and most of the supratidal habitat

will disappear by TY20. By TY40, the 71 acres of intertidal habitat will be gone.

Therefore, if no additional actions are taken, the year of disappearance (YOD) for

the entire island is TY40.

Future Ecosystem Losses Without Project

If no action is taken to restore East Island, significant environmental resources will

be lost that have institutional, public, and technical importance.

 71 acres of Essential Fish Habitat (EFH)

 Critical habitat for piping plover

 178 acres of supratidal habitat

 Storm surge protection for western Terrebonne Parish

 Protection of oil and gas infrastructure

Wine Island

Description

Wine Island, located approximately 2.5 miles northeast of East Island and 3.9 miles

west of Timbalier Island, lies on Wine Island Shoal, with Wine Island Pass to the

west and Cat Island Pass to the east. Historically, Wine Island was the

easternmost of the Isles Dernieres. It was approximately three miles in length, and

located across the mouth of the present Wine Island/Cat Island Pass (Penland, et

al., 2005). By the mid-20th Century the island had migrated north and eroded

away. What is now called Wine Island is a dredge spoil disposal site, associated

with the Houma Navigation Canal (HNC). In 1991 the present configuration was

created when the South Terrebonne Tidewater Management and Conservation

District (District) constructed the rock containment dike and the USACE filled it

with dredge spoil from the HNC. The original restoration created a 24-acre island,

approximately 1,500 ft, east to west. The island was vegetated with a mixture of

cordgrass, black mangrove, and ryegrass by the District and the Coastal

Restoration Division of the Louisiana Department of Natural Resources in the same

year. In 1992 Hurricane Andrew overwashed the island, decimated the vegetation,

and washed approximately one-third of the land away. Plans for additional rock

structures, dredge spoil placement, and vegetation planting never materialized and

responsibility for the island was transferred to the Louisiana Department of

Wildlife and Fisheries. The present island is small; approximately 800 ft in eastwest dimension. The island is no longer contained within the revetment: its area

has been reduced significantly and its footprint has migrated north such that about

one third of it presently lies outside the subcircular ring of rocks.

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The island is a thriving bird rookery. There is strong public sentiment, from

Terrebonne Parish residents and Parish government, to protect and expand Wine

Island.

Figure 2-22. Aerial Photograph of Wine Island in 2008

Proposed Projects

The Wine Island Restoration project was nominated by the Louisiana Department

of Wildlife and Fisheries (LDWF) for CIAP funding. The project would increase the

size of Wine Island through the use of hydraulically dredged material from the

Houma Navigation Canal. Due to the uncertainty of project implementation, the

Wine Island Restoration project was not included in the analysis. Furthermore, the

State is pursuing the use of these CIAP funds as cost share for the LCA project. No

additional projects, including CWPPRA or CIAP projects have been proposed for

Wine Island at this time.

Land loss

It is unknown if the present land mass has been supplemented by subsequent

dredge spoil disposal. Its low relief and sparse vegetation point to periodic

overwash, as does its ongoing migration out of the encircling rock revetment. The

average long-term shoreline change rate between 1956 and 1988 developed from the

atlas of shoreline changes on Louisiana (William et al., 1992) was -21.6 ft/yr. Table

2-5 summarizes the habitat acreages computed for Wine Island for the period of

analysis.

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Table 2-5. Habitat Acres and Year of Disappearance for Wine Island FWOP

Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

Wine

Dune 1 0 0 0 0 0 0 0 TY1

Supratidal 6 4 3 2 1 0 0 0 TY29

Intertidal 6 7 6 5 3 1 0 0 TY35

aYOD: Year of Disappearance

At TY0, the dimensions of Wine Island (i.e. height, width, and depth of each habitat

type) are not sufficient to provide geomorphologic form and ecologic function as

defined in Section 3.3.2.2.1. As seen in Table 2-5, the island has 1 acres of dune

habitat, 5 acres of supratidal habitat, and 6 acres of intertidal habitat. The dune

habitat is expected to disappear by TY1 and most of the supratidal habitat will

disappear by TY29. By TY35, the six acres of intertidal habitat will be gone.

Therefore, if no additional actions are taken, the year of disappearance (YOD) for

the entire island is TY35.

Future Ecosystem Losses Without Project

If no action is taken to restore Wine Island, significant environmental resources will

be lost that have institutional, public, and technical importance.

 6 acres of Essential Fish Habitat (EFH)

 Critical habitat for piping plover

 5 acres of supratidal habitat utilized by the brown pelican and numerous

other shorebirds

 Storm surge protection for western Terrebonne Parish

 Protection of oil and gas infrastructure

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Figure 2-23. View of a brown pelican rookery on Wine Island

Figure 2-24. Typical view of the habitat found on Wine Island and the

nesting brown pelicans

Timbalier Island

Timbalier Island is approximately 7 miles long (USDA, 2007b) and lies in

Terrebonne and Lafourche Parishes. Historical maps of shoreline change have

provided insight into the erosion process during the rapid westward migration by

Timbalier Island. Over the last 115 years, Timbalier Island has migrated 2.5 miles

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to the west by the erosion of its east end and the recurve spit extension of its west

end. With this westward migration, Timbalier Island has developed two distinct

shoreline change rate regimes (USACE, 2004c).

Figure 2-25. Aerial Photograph of Timbalier Island in 2008

Proposed Project

The goal of CWPPRA project TE-53 (Enhancement of Barrier Island Vegetation

Demonstration) is to develop cost-effective methods for enhancing vegetative

establishment and growth on barrier island restoration projects. Currently, this

project is in the planning phase. Two possible project sites have been proposed 

the site of the Timbalier Island Dune and Restoration project (TE-40), and the New

Cut Dune and Marsh Restoration project (TE-37) site (LDNR, 2009b). TE-53 is

currently waiting project phase authorization.

Due to the uncertainty of project implementation, CWPPRA project TE-53 was not

included in the analysis for the island. No additional projects, including CWPPRA

or CIAP projects have been proposed for Timbalier Island at this time.

Landloss

The average historic rate of shoreline change for the eastern portion of Timbalier

Island was -42.9 ft/yr between 1887 and 2002 with a range of -48.6/-37.3 ft/yr.

Between 1988 and 2002, the average short-term erosion rate accelerated to -179.4

ft/yr with a range of -205.5/-153.3 ft/yr for the eastern portion. The high rates of

negative change reflect the impact of the 1992 and 2002 hurricanes. Conversely,

with the western migration of Timbalier Island, the western portion of the island

has historically shown a lower rate of shoreline change. The average historic erosion

rate for the western portion is -4.1 ft/yr with a range of -31.0/+20.9 ft/yr between

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1887 and 2002. The western portion has experienced an average short-term erosion

rate between 1988 and 2002 of 13.4 ft/yr with a range of -118.7/+31.9 ft/yr. The

combination of the 1985/1992/2002 hurricanes and disruption of the westward

sediment transport by the Belle Pass jetties have all contributed to the high rates of

shoreline change in this area (USACE, 2004c). The average long-term shoreline

change rate between 1956 and 1988 developed from the atlas of shoreline changes

on Louisiana (William et al., 1992) was -32.5 ft/yr.

For this study, the island dimensions and habitat composition of Timbalier Island

were determined by applying vertical adjustments (subsidence and sea level rise)

and horizontal adjustments (background erosion and overwash) to the existing

island footprint for each target year (see Appendix L).Table 2-6 summarizes the

habitat acreages computed for Timbalier Island for the period of analysis.

Table 2-6. Habitat Acres and Year of Disappearance for Timbalier Island

FWOP.

Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

Timbalier

Dune 57 53 31 8 0 0 0 0 TY20

Supratidal 549 529 266 286 93 18 1 0 TY46

Intertidal 374 373 541 392 289 149 37 2 >TY50

aYOD: Year of

At TY0, the dimensions of Timbalier Island (i.e. height, width, and depth of each

habitat type) are not sufficient to provide geomorphologic form and ecologic function

as defined in Section 3.3.2.2.1. As seen in Table 2-6, the island has 57 acres of dune

habitat, 549 acres of supratidal habitat, and 374 acres of intertidal habitat. The

dune habitat is expected to disappear by TY20 and most of the supratidal habitat

will disappear by TY40. By TY50, all but two acres of intertidal habitat will be

gone.

Future Ecosystem Losses Without Project

If no action is taken to restore Timbalier Island, significant environmental

resources will be lost that have institutional, public, and technical importance.

 374 acres of Essential Fish Habitat (EFH)

 Critical habitat for piping plover

 549 acres of supratidal habitat

 Storm surge protection for eastern Terrebonne and Lafourche Parishes

 Protection of oil and gas infrastructure

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Figure 2-26. View of the sand dunes created on Timbalier Island during a

recent restoration project

Figure 2-27. Shoreline protection feature located on Timbalier Island

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Figure 2-28. View of the many shorebirds that utilize Timbalier Island

East Timbalier Island

East Timbalier Island is approximately 3.6 miles long (USDA, 2007b) and lies east

of Little Pass Timbalier and directly west of the Bayou Lafourche headland. East

Timbalier Island is occupied by a major oil and gas operation at the inshore

Timbalier Bay Field. The island and surrounding bay supports major offshore

production facilities. East Timbalier Island is known for the massive rip-rap seawall

along its Gulf shoreline and numerous revetments landward of it. The combination

of the position of East Timbalier Island immediately downdrift of the Bayou

Lafourche headland and the Belle Pass jetties create one of the most erosional areas

in coastal Louisiana (USACE, 2004c).

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Figure 2-29. Aerial Photograph of East Timbalier Island in 2008

Proposed Project

There are two proposed CIAP project on East Timbalier. The first project proposes

the creation of approximately of 3,200 linear feet of segmented breakwaters, 190

acres of supratidal habitat, and 180 acres of intertidal habitat. The second project

would close a breach in the island and rebuild a larger, wider dune and beach along

the gulfward shoreline.

Due to the uncertainty of project implementation, neither project was included in

the analysis. No additional projects, including CWPPRA or CIAP projects have

been proposed for East Timbalier Island at this time.

Landloss

The average historic erosion rate between 1887 and 2002 was -61.2 ft/yr with a

range of -74.3 to -49.2 ft/yr. The average short-term erosion rate between 1988 and

2002 decreased to -36.3 ft/yr with a range of -65.5 to -4.9 ft/yr. The erosion rate

diminished here in spite of the 1992 and 2002 hurricanes. This shoreline erosion

decrease is partially related to the construction of CWPPRA restoration project TE25/30 in 2000, which created approximately 109 acres of new land (USACE, 2004c).

The average long-term shoreline change rate between 1956 and 1988 developed

from the atlas of shoreline changes on Louisiana (William et al., 1992) was -21.4

ft/yr.

For this study, the island dimensions and habitat composition of East Timbalier

Island were determined by applying vertical adjustments (subsidence and sea level

rise) and horizontal adjustments (background erosion and overwash) to the existing

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island footprint for each target year (see Appendix L). Table 2-7 summarizes the

habitat acreages computed for East Timbalier Island for the period of analysis.

Table 2-7. Habitat Acres and Year of Disappearance for East Timbalier

Island FWOP

Island Habitat

Type

Habitat Acres

YODa

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 (TY)

East

Timbalier

Dune 7 1 1 0 0 0 0 0 TY10

Supratidal 129 74 60 46 9 2 1 0 TY43

Intertidal 173 133 140 111 98 49 17 4 >TY50

aYOD: Year of Disappearance

At TY0, the dimensions of East Timbalier Island are not sufficient to provide

geomorphologic form and ecologic function as defined in Section 3.3.2.2.1. As seen in

Table 2-7, the island has 7 acres of dune habitat, 129 acres of supratidal habitat,

and 173 acres of intertidal habitat. The dune habitat is expected to disappear by

TY10 and the supratidal habitat will disappear by TY43. By TY50, all but four

acres of intertidal habitat will be gone.

Future Ecosystem Losses Without Project

If no action is taken to restore East Timbalier Island, significant environmental

resources will be lost that have institutional, public, and technical importance.

 173 acres of Essential Fish Habitat (EFH)

 Critical habitat for piping plover

 129 acres of supratidal habitat

 Storm surge protection for western Lafourche Parish

 Protection of oil and gas infrastructure

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Figure 2-30. View of the oil and gas facilities protected by East Timbalier

Island

Figure 2-31. Aerial view facing north of the western tip of East Timbalier

Island

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3.0 ALTERNATIVES

3.1 PLAN FORMULATION RATIONALE

3.1.1 Plan Formulation Rationale

Alternatives for the proposed action were formulated in consideration of Study Area

problems and opportunities, as well as study goals, objectives and constraints. As

specified in ER 1105-2-100, four criteria were considered during alternative plan

screening: completeness, effectiveness, efficiency, and acceptability.

3.1.2 Plan Formulation Criteria

3.1.2.1 Completeness

Completeness is the extent that an alternative provides and accounts for all

investments and actions required to ensure the planned output is achieved. This

criterion may require comparison of the plan to other public and private plans if

those plans affect the outcome of the project. Completeness also includes

consideration of real estate issues, O&M, monitoring, and sponsorship factors.

Adaptive management plans formulated to address Study uncertainties also have to

be considered.

3.1.2.2 Effectiveness

Effectiveness is defined as the degree to which the plan will achieve the planning

objective. The plan must make a significant contribution to the problem or

opportunity being addressed.

3.1.2.3 Efficiency

The Study must be a cost-effective means of addressing the problem or opportunity.

The plan outputs cannot be produced more cost-effectively by another institution or

agency.

3.1.2.4 Acceptability

A plan must be acceptable to Federal, State, and local government in terms of

applicable laws, regulation, and public policy. The Study should have evidence of

broad-based public support and be acceptable to the non-Federal cost sharing

partner.

3.1.3 Environmental Operating Principles

In 2002, the USACE formalized a set of Environmental Operating Principles

applicable to decision-making in all programs. The principles are consistent with

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NEPA; the Army Strategy for the Environment; other environmental statutes, and

the WRDAs that govern USACE activities. The Environmental Operating Principles

inform the plan formulation process and are integrated into all project management

processes. Alternatives were formulation for this Study consistent with the

Environmental Operating Principles.

The USACE Environmental Operating Principles are:

 Strive to achieve environmental sustainability, and recognize that an

environment maintained in a healthy, diverse, and sustainable condition is

necessary to support life;

 Recognize the interdependence of life and the physical environment, and

proactively consider environmental consequences of USACE programs and

act accordingly in all appropriate circumstances;

 Seek balance and synergy among human development activities and natural

systems by designing economic and environmental solutions that support and

reinforce one another;

 Continue to accept corporate responsibility and accountability under the law

for activities and decisions under our control that impact human health and

welfare and the continued viability of natural systems;

 Seek ways and means to assess and mitigate cumulative impacts to the

environment and bring systems approaches to the full life cycle of our

processes and work;

 Build and share an integrated scientific, economic, and social knowledge base

that supports a greater understanding of the environment and impacts of our

work; and

 Respect the views of individuals and groups interested in USACE activities,

listen to them actively, and learn from their perspective in the search to find

innovative win-win solutions to the Nations problems that also protect and

enhance the environment.

3.2 MANAGEMENT MEASURES

Management measures were developed to address Study Area problems and to

capitalize upon Study Area opportunities. A management measure is a feature or

an activity that can be implemented at a specific geographic site to address one or

more planning objectives. A management measure can be combined with other

management measures to form island strategy, which were then combined to form

alternative plans.

3.2.1 Development of Management Measures

Management measures were derived from a variety of sources including prior

restoration projects, prior studies, the National Environmental Policy Act (NEPA)

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public scoping process, and the multidisciplinary, interagency project delivery team

(PDT) consisting of experts from State and Federal agencies and the private sector.

Various permutations of scales and locations were considered.

As part of the Feasibility Scoping Meeting planning step, a Value Engineering (VE)

study was conducted to identify potential modifications of restoration measures and

plan configurations that could improve the performance and cost effectiveness of the

preliminary alternatives (VMS, 2009). The results of the VE study for the project

were fully considered and used to refine the conceptual alternative plans during

alternative plan formulation.

In order to develop a reasonable set of alternatives for the LCA TBBSR Study, a

wide range of management measures was first identified. Experience of the PDT

along with information presented in the VE study, comments from the public

scoping meeting, and supporting data (e.g. geospatial data, surveys, previous

restoration projects and measures) were used to establish the list of strategies and

measures that were assessed during the screening process. The management

measures were divided into hard- and soft- structural measures. The following

sections present the descriptions of the management measures that were

considered.

3.2.2 Description of Management Measures

3.2.2.1 Hard-Structural Measures

3.2.2.1.1 Breakwaters

The main function of breakwaters is to trap sand by reducing wave energy behind

the structure, therefore slowing littoral drift and often creating a salient or tombolo

behind the structure. The following variations of breakwaters were evaluated:

 Segmented Breakwaters (specific location)

 Continuous Breakwaters (specific location)

 Segmented Breakwaters (entire island)

 Continuous Breakwaters (entire island)

3.2.2.1.2 Revetments

The purpose of revetments is to protect upland property. The structures are

constructed as rubble mounds, with a stone size determined by analysis of the wave

climate.

Revetments limit the movement of sediment from behind the revetment to the

active littoral system seaward of it. Due to the energy dissipating nature of rubble

mound, revetments considerably reduce the probability of scour. Revetments may

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be utilized in a continuous or segmented orientation (USACE, 2004c). The following

variations of revetments were evaluated:

 Segmented Revetments (specific location)

 Continuous Revetment (specific location)

 Segmented Revetments (entire island)

 Continuous Revetment (entire island)

3.2.2.1.3 Shoreline Groins

Shoreline groins are shore-perpendicular structures that are designed to trap

longshore sediment transport. They have been constructed from many different

materials including steel sheet piles, concrete sheet piles, wood panels with wood

piles, and rubble mounds (including concrete roadway and sidewalk debris).

Shoreline groins are typically designed to extend from the dry beach across the surf

zone (USACE, 2004c).

3.2.2.1.4 Terminal Groins

Terminal groins are structures constructed perpendicular to the shoreline at the

ends of barrier islands or littoral cells. They can also be located adjacent to nonstabilized inlets in order to avoid or minimize sediment losses to these water bodies.

3.2.2.1.5 Sand Fencing

Sand fences are typically an integral part of dune restoration projects and are sited

on the dune, where they are less susceptible to wave energy. Sand fences capture

the aeolian transport of fine grain sand and add elevation to the dune as the sand

accumulates.

3.2.2.1.6 Sunken Barges/ships

This measure consists of utilizing barges or ships as an unconventional breakwater.

These structures can be used both in a sunken or floating configuration. Sunken

barges/ships are often filled with rocks and/or water and placed in a shore-parallel

orientation.

3.2.2.1.7 Floating Barges/ships

This measure consists of utilizing barges or ships as an unconventional breakwater.

The floating vessels would be anchored or moored in a shore-parallel orientation.

3.2.2.1.8 Sheet Pile

A sheet pile wall is a row of interlocking, vertical piles driven to form a straight wall

or bulkhead, often strengthened by a horizontal cap or wale (USACE, 1994). These

structures, which can be built from steel, aluminum, timber, or concrete, are used

as effective means of stabilizing a shoreline that is subject to low-moderate waves.

Sheet piles are typically driven at the toe of the fill or structure to resist scour at its

base. They are curved or stepped face to limit wave overtopping, and are sometimes

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backfilled to raise the land elevation behind the structure (Sorensen et al., 1984).

The following variations of sheet pile were evaluated:

 Segmented Sheet Pile (specific location)

 Continuous Sheet Pile (specific location)

 Segmented Sheet Pile (entire island)

 Continuous Sheet Pile (entire island)

3.2.2.1.9 Pass Closures

Pass closures would consist of closing navigable passes via hardened structural

methods. These measures would reduce the tidal prism and salinity intrusion in

the estuary.

3.2.2.1.10 Canal Plugs

Placing plugs in strategic locations can isolate interior marshes and back-barrier

features from hydrologic influences. Earthen plugs can be used to close off

waterways, and when access is needed, they can be removed and subsequently

replaced. Such arrangements are typically more cost-effective than structures such

as floodgates.

3.2.2.2 Soft-Structural Measures

3.2.2.2.1 Dune Restoration

This measure consists of construction of a sand dune system using external

sediment sources. Sediment of suitable grain size and physical properties is

dredged from offshore sources and transported to the restoration location. The

material is then placed along the shoreline reach to restore the dune profile of the

barrier shoreline as specified in the topographic profile developed for the restoration

plan. Containment structures may be used to control placement of sediment. This

measure would recreate the dune system and restore the form and function of the

shoreline.

3.2.2.2.2 Marsh Creation

This measure consists of construction of containment dikes, using in situ sediment,

and creation of a marsh platform using sediment of suitable grain size and physical

properties transported to the marsh location from an external source. Marsh

platforms landward of barrier shorelines provide a foundation for rollover of the

dune ridge and beach shoreface, allowing the barrier shoreline to migrate landward

in response to storms, waves, and currents. The migrating shoreface material

continues to provide benefits even though some wetland loss occurs during the

rollover process.

3.2.2.2.3 Beach Restoration (depth of closure to dune)

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This measure consists of widening the existing shoreline and profile to the closure

depth, using sediment of suitable grain size and physical properties transported to

the restoration site from an external source. This enhancement provides protection

to the dune while also providing sediment in the littoral system to feed down drift

beaches.

3.2.2.2.4 Subtidal Sediment Placement

This form of beach restoration involves placing stockpiles of sand in strategic

subtidal locations. The method has a lower initial construction cost, but requires

more maintenance because coastal processes move the material not only down the

beach but also offshore, causing greater loss of material. Subtidal sediment

placement has the same reasons for implementation as beach restoration and the

same advantages and disadvantages (USEPA, 1997a).

3.2.2.2.5 Addition of Sediment into Near-shore Environment

This method involves the placement of beach fill material in a sand bar just offshore

of the surf zone. To be successful, the placement must be within the active portion

of the beach profile. The sand will gradually move onshore under the influence of

waves and currents, increasing the beach width.

3.2.2.2.6 Breach Closure

This measure involves the placement of dredged material into breaches in the

barrier island, most often caused by hurricanes. Positive environmental benefits

include the conversion of intertidal habitat to supratidal and dune habitat. If left

unmitigated, breaches usually widen rapidly and may turn into tidal passes. The

closing of breaches fortifies and stabilizes the island, while protecting existing

intertidal habitat. The New Cut Dune/Marsh Restoration Project (TE-11a/TE-37),

located between East Island and Trinity Island is an example of a recentlyconstructed breach closure project.

3.2.2.2.7 Small Marsh Island Construction on Bayside for Bird Habitat

This measure consists of using dredged material to build small islands on the bay

side of the barrier island reach. The measure was proposed as an emergency

restoration to replace lost bird habitat on Raccoon Island, following Hurricane

Andrew (USEPA, 1993).

3.2.2.2.8 Vegetation Planting

Vegetation plantings are a typical component of barrier island dune and marsh

restoration projects, and are often installed to stabilize dredged material and

supplement natural colonization and recruitment.

3.2.2.2.9 Herbivore Control

This measure is used to reduce the damage to coastal wetlands caused by the South

American herbivorous rodent, Myocastor coypus (Nutria). Examples of this

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measure are an incentive payment program to encourage nutria harvesting and

measures implemented on-site, such as wire mesh cages to retard herbivory.

3.2.2.2.10 Bio-engineered Oyster Reefs

This measure utilizes shell material placed at an elevation that would periodically

break the surface of the water, in order to create "islands," as well as substrates for

oyster growth. The Louisiana Department of Wildlife and Fisheries recommends

using traditional cultch material to rebuild certain islands, eroded points or spits,

and relict shell islands. These islands or bars provide important habitat for fish

and invertebrate species, and, if they become vegetated, important nesting habitat

for some species of shore birds.

3.2.2.2.11 Spit Creation (E&T Habitat)

A spit is a linear beach extending from a headland designed to create endangered

and threatened species (E&T) habitat. Spit creation may be a viable restoration

measure especially if situated where it would benefit from natural longshore

sediment transport.

3.2.2.2.12 Backfilling Canals

Canal backfilling involves depositing dredged or bulldozed material (from the canal

spoil banks or elsewhere) into a canal. Differentiating this measure from marsh

creation is the grade to which the deposited dredge material is elevated (elevation of

backfilled canals must coincide with the elevation of the adjacent undisturbed baybottom or marsh).

3.2.3 Screening/Evaluation of Management Measures

3.2.3.1 Initial Screening

The identified measures were selected and screened based upon experience with

previous restoration efforts, knowledge of the Study Area, conventional scientific

theory, best professional judgment, and consideration of the study objectives.

Management measures were first screened based on their ability to meet the

following five (5) criteria:

 Consistency with Authorization and Purpose - measure is fully consistent

with study authorization and purpose;

 Achievement of Planning Objectives - measure is fully supportive of planning

objective(s);

 Efficiency - measure directly influences the area(s) of greatest need;

 Environmental Impacts - measure presents no readily apparent potential for

adverse environmental impacts; and

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 Engineering Feasibility - measure directly supported by acceptable

engineering and industry practices.

These criteria were deemed critical for achieving the Study goals. Each measure

that could reasonably achieve the planning objectives was maintained for

consideration under the final screening level described in the next section.

3.2.3.1.1 Hard-structural Measures Screening

The following sections describe the hard-structural measures that were evaluated

and the application of the screening criteria to either eliminate or carry each

measure forward. An important factor that must be considered when evaluating

hard structures is the interplay of sea level rise, land subsidence, and the lack of

sediment input into the littoral systems. These factors result in a gradual

northward or landward movement of some of the barrier islands, or parts of the

islands (Penland, et al., 2005). As the distances between the shoreline and fixed

offshore erosion prevention measures increase, particularly after major storm

events roll the beach/dune system back over the bay or marsh, the measures slowly

lose their effectiveness. This, coupled with the lack of suitably supportive

foundation substrate in many locations, means that detailed geological

investigations must precede any decision regarding use of such measures.

Segmented Breakwaters (Specific Location)

Segmented breakwaters were carried forward for further consideration because this

measure, in certain situations, may stabilize the shoreline and significantly reduce

shoreline erosion for the protected area. Site-specific modeling should be conducted

to ensure that the segmented breakwater will not interrupt the natural longshore

sediment transport system and adversely impact adjacent shoreline reaches.

Continuous Breakwaters (Specific Location)

Considerable discussion occurred regarding the long-term, system-wide problems

created by some of the proposed hard-structural measures, notably breakwaters.

These structures interfere with the normal longshore and cross-shore movement of

sediment in the coastal system. They introduce a systemic disruption into the

barrier island shoreline processes, one that will likely be beneficial in some

situations and detrimental in others. While they may be effective in certain local

applications, they may result in increased erosion elsewhere in the system (Dean,

1999; Douglass, 2002; National Research Council, 1995). Due to potential

environmental impacts, the indiscriminate installation of continuous breakwaters

along entire or partial lengths of island shoreline did not pass screening.

In addition to the potential adverse environmental impacts, these structures do not

introduce additional sediment into the already sand-starved system. The

conceptual sediment budget for LCA Province III, which extends from the

Caminada/Fourchon Headland westward to Vermilion Bay, indicates that sediment

moves in a westward direction from the Headland, past the Timbalier Islands then

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into Terrebonne Bay. The dominant movement in the Isles Dernieres is complex: it

moves to the east, into Terrebonne Bay, to the west, into the Isles Dernieres Sink

and toward Grand Caillou Bayou, and also to the south, offshore (Rosati, et al.,

2008, draft letter report).

Segmented Breakwaters (Entire Island)

Segmented breakwaters placed around an entire island were eliminated from

further consideration because they present high a potential for adverse

environmental impacts. While the impact from breakwaters may appear to be

positive as reduced erosion rates along portions of the shorelines would enhance

project performance and potentially increase the interval between re-nourishment

events, these benefits would be offset by significant adverse impacts that would

result from the interruption of longshore sediment transport. This interference

with sediment transport processes would increase the rates of erosion and shoreline

retreat to adjacent reaches of the barrier shoreline (USACE, 2009).

Continuous Breakwaters (Entire Island)

Continuous breakwaters placed around an entire island were eliminated from

further consideration because of the potential impacts discussed for continuous

breakwaters (specific locations).

Segmented Revetments (Specific Location)

Segmented revetments placed at specific locations were eliminated because

potential environmental impacts. They will interrupt normal movement of sand

along the shoreline, longshore and cross-shore and result in long-term negative

impact although they may reduce short-term erosion. Also, rocks placed on

sediment can settle significantly. Some form of foundation protection (e.g., rock

filled geotextile mats/sheets) is needed to limit this settlement. In some cases, the

substrate may be too unstable to support rock structures, even with foundation

protection.

Continuous Revetment (Specific Location)

Continuous revetments placed at specific locations were eliminated because of

potential environmental impacts. This measure consists of the construction of a

rock shoreline. This measure may stabilize the shoreline and may reduce shoreline

erosion for the protected area. However, a rock shoreline would adversely impact

threatened and endangered species such as the piping plover and the Kemps Ridley

sea turtle, by eliminated nesting and feeding areas (USACE, 2009). The Wetland

Value Assessment (WVA) methodology, which quantifies habitat benefits of

restoration projects, acknowledges this by assigning a considerably lower surf-zone

habitat value for shorelines protected with revetments (CWPPRA, 2002).

Continuous revetments can also adversely impact longshore sediment transport

processes. In the 1950s, a continuous rock seawall was placed on the seaward side

of East Timbalier Island to protect the island and associated oil and gas

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infrastructure from wave impacts. However, the seawall disrupted the natural

wave processes and distorted the normal nearshore profile. This resulted in the

formation of a steep, subaqueous scarp. Due to the seawall and associated scarp,

little, if any, sand could be deposited on the beach by longshore transport. This

accelerated the natural erosional processes because the sand material winnowed

through the seawall was not replaced by longshore sediment transport.

Consequently, the beach retreated more quickly from the seawall, leaving it

stranded in open water (LGS, 1995). This phenomenon was also described by

Penland and Boyd (1981). According to the authors, East Timbalier Island

increased size between 1935 and 1956. After the construction of the seawall, the

size of the island began rapidly decreasing. The authors attributed the decline to

the construction of the seawall rather than cyclone activity.

Also, rocks placed on sediment can settle significantly. Some form of foundation

protection (e.g., rock filled geotextile mats/sheets) is needed to limit this settlement.

In some cases, the substrate may be too unstable to support rock structures, even

with foundation protection. Furthermore, revetments cannot counter the effects of

subsidence and sea level rise (LGS, 1995). For this reason, continuous revetments

were eliminated from further consideration for Raccoon, Whiskey, Trinity, East,

Timbalier, and East Timbalier Islands.

However, Wine Island is unique in that it was once surrounded by a boulder

revetment to hold dredged material from the HNC. The island is no longer

contained within the revetment. One restoration option being considered by the

PDT involves restoring the island within the boulder revetment, through beneficial

use of sediment dredged from the HNC. Therefore, continuous revetments will be

carried forward for Wine Island only.

Segmented Revetments (Entire Island)

Segmented revetments placed around an entire island were eliminated from further

consideration because they present high potential for adverse environmental

impacts. This measure may stabilize the shoreline and may reduce shoreline

erosion for the protected area. However, a rock shoreline would adversely impact

threatened and endangered species such as the piping plover and the Kemps Ridley

sea turtle by eliminating nesting and feeding areas (USACE, 2009). Further, the

rock shoreline would interrupt the natural longshore sediment transport system

and impact adjacent shoreline reaches not protected by hard stabilization (USACE,

2009). For this reason, segmented revetments placed around the entire island were

eliminated from further consideration.

Continuous Revetment (Entire Island)

Continuous revetments were removed from further consideration for the same

reasons as the continuous revetments at specific locations.

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Shoreline Groin

Although groins in general are not effective in reducing cross-shore erosion (i.e.

overwash from beach/dune into and across the back-barrier marsh and mudflats),

they are effective in mitigating longshore transport (Kraus et al, 1994). However,

during near-normal wave incidences (i.e. during typical storm events), a shoreline

groin system can create strong local currents and rip currents which can contribute

to the offshore movement of beach materials (USACE, 2008b). Therefore, shoreline

groins were eliminated from further consideration.

Terminal Groin

Terminal groins contribute to significantly less storm-induced currents than

shoreline groin fields because they consist of a single structure placed at the end of

the island. Furthermore, they are effective in reducing longshore erosion by

capturing sediment that would otherwise be lost through offshore transport and

deposition. Therefore, terminal groins were carried forward for further

considerations.

Special consideration must be given to the placement of these features because of

the potential adverse impacts that could result from the interruption of longshore

sediment transport. This interference with sediment transport processes would

increase the rates of erosion and shoreline retreat to adjacent reaches of the barrier

shoreline.

Sunken Barges/Ships

Use of surplus ships or barges, whether sunk as a series of breakwaters or anchored

to form a nearshore wave-attenuating array, raises a number of engineering and

environmental issues. Given the shoaling nature of the nearshore environment,

getting barges or vessels into correct positions to function as a detached breakwater

system, and then sinking them, would be difficult to achieve with any degree of

accuracy and therefore presents a significant engineering feasibility issue.

Permitting such a system would also be difficult because of the potential for

hazardous materials releases (i.e. environmental impacts), the need for extensive

dredging, and other similar issues. The most obvious question about use of

anchored vessels is how to ensure that they stay where anchored, particularly

considering the magnitude of recent hurricanes and the damage wrought by loose

vessels when they are blown ashore. Given the number and scattered distribution

of petroleum extraction and processing structures in the Terrebonne Basin and the

unknown nature of future storm tracks, the potential for damage from loose vessels

must be a serious consideration. Due to these issues, sunken barges/ships were

eliminated from further consideration.

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Floating Barges/Ships

This measure was eliminated from further consideration because of the potential

environmental impacts and engineering feasibility issues discussed for sunken

barges/ships.

Segmented Sheet Pile (Specific Location)

Segmented sheet pile was eliminated from further consideration because its longterm effectiveness would be significantly reduced due to local subsidence and

historical migration trends. Therefore, it would not meet the planning objectives of

the Study. Furthermore, it could potentially interrupt the natural longshore

sediment transport and could present adverse environmental impacts to the

shoreline reaches.

Continuous Sheet Pile (Specific Location)

Continuous sheet pile was eliminated from further consideration for the same

reasons as segmented sheet piles at specific locations.

Segmented Sheet Pile (Entire Island)

Segmented sheet pile was eliminated from further consideration for the same

reasons as segmented sheet piles at specific locations.

Continuous Sheet Pile (Entire Island)

Continuous sheet pile was eliminated from further consideration for the same

reasons as segmented sheet piles at specific locations.

Pass Closures

Simple hydrodynamic considerations dictate that plugging one pass means that the

volume of water it conveyed will have to be accommodated elsewhere, either by

existing passes or newly-created breaches. Furthermore, the structures themselves

would be highly susceptible to breaching and could disrupt the tidal prism of the

system. Therefore, pass closures did not pass the initial level screening because of a

lack of efficiency and ability to achieve the planning objectives

Canal Plugs

Canal plugs were carried forward for further consideration because they appeared

to be an effective means of preventing breaches and further land loss.

3.2.3.1.2 Soft-structural Measures Screening

The following sections describe the soft-structural measures that were evaluated

and the application of the initial level screening criteria to either eliminate or carry

each measure forward.

Dune Restoration

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Dune restoration is a proven barrier island restoration measure in coastal

Louisiana. It met all five of the initial screening criteria and was carried forward

for further consideration. Restoring the barrier island system through placement of

sand would help mitigate storm damage to natural and man-made components in

the Study Area. However, the dune system would continue to erode if other

measures such as periodic re-nourishment are not implemented, or until longerterm projects reestablish sediment supply for this region of the Gulf shoreline.

Marsh Creation

Marsh creation is a proven barrier island restoration measure in coastal Louisiana.

It met all five of the initial screening criteria and was carried forward for further

consideration. Marsh restoration in combination with other barrier island

restoration measures would increase the extent of the bay intertidal habitats. Back

barrier marshes, along with their related hydrologic and biological processes,

provide unique habitats that are crucial to the viability of migratory birds,

commercial and recreational fisheries, and a great variety of terrestrial and aquatic

species. Marsh platforms constructed landward of barrier shorelines provide a

foundation for rollover of the dune ridge and beach shoreface, allowing the barrier

shoreline landforms to migrate landward in response to storms, waves, and

currents. The migrating shorelines continue to provide benefits even though some

wetland loss occurs during the rollover process (USACE, 2009).

Beach Restoration

Beach restoration is a proven barrier island restoration measure in coastal

Louisiana. It met all five of the initial screening criteria and was carried forward

for further consideration. This measure would restore the shoreface, widen the

geomorphic structure of the island, and increase the sediment available for

longshore transport which could benefit adjacent barrier shoreline.

Subtidal Sediment Placement

Placement of sediment in the shallow open water areas behind the barrier island

would serve similar functions as back-barrier marsh creation. These shallow-water

environments would provide critical fish and wildlife habitat as well as provide a

foundation for rollover of the dune ridge and beach shoreface, allowing the barrier

shoreline landforms to migrate landward in response to storms, waves, and

currents. Subtidal sediment placement met all five of the initial screening criteria

and was carried forward for further consideration.

Addition of Sediment into Nearshore Environment

Addition of sediment to the nearshore environment met all five of the initial

screening criteria and was carried forward for further consideration. This measure

involves the placement of sediment in the gulf intertidal habitat from the gulf side

beach slope to shallow open water. The environmental benefits of this measure are

similar to the previous two elements in that it will restore the intertidal portion of

the shoreface, widen the geomorphic structure of the island, and increase the

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sediment available for longshore transport, which could benefit adjacent barrier

shoreline.

Breach Closure

Breach closure met all five of the initial screening criteria and was carried forward

for further consideration.

Small Marsh Island Construction on Bayside

Marsh island construction met all five of the initial screening criteria and was

carried forward for further consideration. This restoration measure would provide

environmental benefits by creating habitat for sea birds and wading birds and to

strengthen the overall island complex without destroying existing vegetations.

Vegetation Planting

Vegetation planting met all five of the initial screening criteria and was carried

forward for further consideration. Vegetation plantings are a common component of

barrier island dune and marsh restoration projects and are often installed to

stabilize dredged material and supplement natural colonization.

Herbivory Control

Herbivory control met all five of the initial screening criteria and was carried

forward for further consideration. Herbivory control measures (nutria excluders,

trapping, and hunting) may be used in conjunction with other measures to increase

the likelihood of project success especially in areas of high nutria populations.

Bio-engineered Oyster Reefs

Bio-engineered oyster reefs are currently being evaluated as a CWPPRA

demonstration project (LA09) to determine their effectiveness at reducing shoreline

retreat. No published reports were available that indicated bio-engineered oyster

reefs would achieve the goals and objectives of the Study. Therefore they were

eliminated from further consideration. However, the measure may be reconsidered

in preconstruction, engineering, and design (PED) if the CWPPRA demonstration

project proves that they are effective.

Spit Creation

Spit creation met all five of the initial screening criteria and was carried forward for

further consideration. This measure involves using dredged material to construct a

linear beach extending from a headland.

Backfilling Canals

Backfilling canals involves placing sediment in oil and gas access canals. The

measure met all five of the initial screening criteria and was carried forward for

further consideration. Backfilling canals would increase beach, dune, and marsh

habitat, restore natural hydrology and barrier island rollover capacity, and improve

the structural integrity of the island.

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3.2.3.1.3 Results

Qualitative screening of 31 measures (19 hard-structural and 12 soft-structural)

proposed in the initial array resulted in the elimination of 15 measures and the

retention of 16 measures to be carried forward for more detailed evaluation in the

second level of screening. These management measures were determined to be

consistent with specific USACE policies for ecosystem restoration, and Federal

laws, regulations, and Executive Orders. The measures that were carried forward

include the following:

 Segmented Breakwaters

 Continuous Revetments (Wine Island Only)

 Terminal Groin

 Sand Fencing

 Canal Plugs

 Dune Restoration

 Marsh Creation

 Beach Restoration

 Subtidal Sediment Placement

 Addition of Sediment into Nearshore Environment

 Breach Closure

 Small Marsh Island Construction on Bayside

 Vegetative Planting

 Herbivory Control

 Spit Creation

 Backfilling Canals

3.2.3.2 Second Level Screening

The second level screening effort built on the initial screening process, with an

emphasis on the combinations of measures that could be used to meet the specific

objectives of the Study. Combinations of management measures are referred to as

island strategies. This screening process was undertaken during a three-day field

trip to the islands (27 to 30 July 2009), involving 20 members of the PDT,

representing the responsible State and Federal agencies and the SJB/CEC team.

Results of the previous screenings were reviewed in situ, along with observations of

the conditions of past CWPPRA and CIAP projects. The days observations were

reviewed, reinforced, and recapitulated during evening discussions, to ensure this

consensus. Based on these discussions, it was determined that no stand-alone

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measure would achieve Study objectives. Furthermore, it was the consensus of the

team that the primary island strategy should be a combination of beach, dune, and

marsh restoration measures. These measures, when used in combination, were the

only management measures capable of meeting the primary objective of restoring

the geomorphologic form and ecologic function of the barrier islands. A detailed

discussion of the development of this island strategy is provided in Section 3.3.2.

Secondary soft-structural measures, such as stand-alone marsh construction,

breach closure, and miscellaneous sand placement were eliminated for further

consideration because the combination beach, dune, and marsh island strategy

would provide similar, but greater benefits. More importantly, these soft-structural

measures could not meet the objectives of the Study as stand-alone measures or in

combination with any other measure.

Sand fences, vegetative planting, herbivory control, segmented breakwaters,

terminal groins, and continuous revetments remained in the evaluation based on

their potential to provide supplemental benefits to the beach/dune/marsh island

strategy proposed above.

The measures that were carried forward include the following:

 Segmented Breakwaters

 Continuous Revetments (Wine Island only)

 Terminal Groin

 Sand Fencing

 Dune Restoration

 Marsh Creation

 Beach Restoration

 Vegetative Planting

 Herbivory Control

Table 3-1 summarizes the management measures that were screened in the initial

and second levels of screening. The table also provides rationales for their

elimination.

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Table 3-1: Management measures removed from further consideration

Management Measure Removed Decision Rationale

Hard-Structural Measures

 Continuous Breakwaters (Specific Location) Segmented Breakwaters (Entire Island) Continuous Breakwaters (Entire Island) Segmented Revetments (Specific Location) Segmented Revetments (Entire Island) Segmented Sheet pile (Specific Location) Continuous Sheet pile (Specific Location) Segmented Sheet pile (Entire Island) Segmented Sheet pile (Entire Island) Continuous Sheet pile (Entire Island)

These measures were eliminated because of the potential environmental impacts(interference with endangered sea turtle nesting and hatchling survival,interference with endangered shore bird foraging) and the inability of thesemeasures to meet the planning objectives of the Study. These structures interferewith the normal longshore and cross-shore movement of sediment in the coastalsystem. They introduce a systemic disruption into the barrier island shorelineprocesses, one that will likely be beneficial in some situations and detrimental inothers. While they may be effective in certain local applications, they may resultin increased erosion elsewhere in the system. The Wine Island revetment isactually a containment dike into which dredge spoil has been pumped. Therevetments on East Timbalier Island have failed to stabilize the shoreline, whichcontinues to migrate north, away from the rocks.

 Shoreline Groin

Shoreline groins were eliminated based on a lack of efficiency. During nearnormal wave incidences (i.e. during typical storm events), a shoreline groinsystem can create strong local currents and rip currents which can contribute tothe offshore movement of beach materials (USACE, 2008b).

 Sunken Barges/ships Floating Barges/ships

Barges/ships were eliminated because of environmental impacts and engineeringfeasibility. Potential for hazardous materials releases, the need for extensivedredging, and other similar issues. Difficulty in securing vessels and ensuringthat they will stay in place during storms. These vessels could cause significantdamage to oil and gas facilities if they were to break loose.

 Pass Closures

Pass Closures were eliminated because of lack of efficiency and ability to achievethe planning objectives. Closing passes is not feasible because hydrodynamicsdictate that plugging one pass will result in the volume of water being shiftedeither to another pass or through newly-created breaches.

 Canal Plugs

Canal plugs were eliminated because they are unable to achieve the planningobjectives of the Study as stand-alone measures. The beach, dune, and marshcreation measures were designed to fill the existing canals, thus, eliminating theneed to install plugs. Therefore, plugs could not be used as supplementarymeasures.

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Management Measure Removed Decision Rationale

Soft-Structural Measures

 Subtidal Sediment Placement

Subtidal sediment placement was eliminated because it would not achieve theplanning objectives of the Study if done as a stand-alone measure. Furthermore,construction of the beach, dune, and marsh components would incidentally resultin subtidal sediment placement. Therefore, subtidal sediment placement wouldnot provide any additional benefit as a supplemental measure.

 Addition of sediment into Nearshore

Environment

Addition of sediment into nearshore environment was eliminated because it wouldnot achieve the planning objectives of the Study if done as a stand-alone project.Furthermore, the beach, dune, and marsh creation measures were designed toplace sediment in the nearshore environment. Therefore, nearshore sedimentplacement would not provide any additional benefit as a supplemental measure.

 Breach Closures

Breach closures would not achieve the planning objectives of the Study as standalone measures. Furthermore, beach, dune, and marsh creation will result in thefilling of existing breaches. Therefore, breach closures would not provide anyadditional benefit as a supplemental measure.

 Small Marsh Island Bird Habitat

Small march island creation would not achieve the planning objectives of theStudy as a stand-alone measure. Furthermore, the creation of a back-barriermarsh will result in bird habitat creation. Therefore, small marsh island creationwould not provide any additional benefits as a supplemental measure.

 Bio-engineered Oyster Reefs

Bio-engineered oyster reefs are currently being evaluated as a CWPPRAdemonstration project (LA08) to determine their effectiveness at reducingshoreline retreat. No published reports were available that indicated bioengineered oyster reefs would achieve the planning objectives of the Study.

 Spit Creation

Spit creation would not achieve the objectives of the Study as a stand-alonemeasure. Furthermore, the creation of beach would provide similar benefits asspit creation. Therefore, it would not provide any additional benefit as asupplemental measure.

 Backfilling Canals

Backfilling canals will not achieve the objectives of the Study as stand-alonemeasures. Beach, dune, and marsh creation will result in the backfilling of canals.Therefore, backfilling canals will not provide any additional benefit as asupplemental measure.

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3.2.3.3 Final Screening

At this point in the screening process, the PDT had concluded that the island

strategies must include a beach, dune, and marsh component in order to achieve the

objectives of the Study. Therefore, the final screening effort, which built upon the

second level screening process, evaluated the use of supplementary measures

including sand fences, vegetative planning, herbivory control, breakwaters,

terminal groins, and continuous revetments (for Wine Island Only). The following

sections discuss the applicability of various combinations of these measures as they

relate to each island.

3.2.3.3.1 Raccoon Island

As part of CWPPRA project TE-29, eight detached segmented breakwaters were

constructed in 1997 at the eastern end of Raccoon Island to reduce shoreline erosion

and promote accretion.

Louisiana State University (LSU) Coastal Studies Institute quantified the effects of

the breakwaters through the analysis of wave data and topographic and

bathymetric surveys. The data derived from wave gauge deployments in October

1997, March 1998, and July 1998 indicated that the breakwaters reduced incident

wave heights by 90% landward of the breakwaters and by 0% in the gaps between

the breakwaters. The breakwaters reduced shore-oblique wave heights by 70%

landward of the breakwaters and 50% in the gaps (LDNR 1999).

Topographic and bathymetric data indicate that salients developed rapidly along

the shoreline and sediment began to accumulate leeward of six of the eight

breakwaters during the first year of monitoring. Shoreline retreat occurred at all

transects located in gaps between breakwaters but at a rate 10% lower than the

long-term shoreline retreat rate which indicates that the breakwaters were

providing some protection to the beach (Figure 3-1). Shoreline retreat rates were

highest east and west of the breakwater system. The transects to the west of the

breakwaters retreated at a rate of 29.7 ft/yr which is 26% greater than the longterm average of 23.6 ft/yr but less than the short-term average of 58.1 ft/yr. The

eastern end of the Study Area eroded more than 69 ft/yr during the first twelve

months of monitoring (LDNR 1999).

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Figure 3-1. Shoreline changes along the TE-29 Study Area from April 1997

to April 1998. The bold numbers above the bars indicate the location of the

eight segmented breakwaters with respect to the individual transects

(LDNR 1999).

Volume changes between the dune and the breakwaters during the first year of

monitoring are presented in Figure 3-2. Increases in volume occurred along all

transects except for the four transects west of the breakwater field (P17 through

P20), P2, and P5 (LDNR 1999).

Figure 3-2. Volume change of individual transects along the TE-29 Study

Area during the first year of monitoring. Bold numbers above the bars

indicate the location of the segmented breakwaters with respect to the

individual transects (LDNR 1999).

In 2005, eight additional breakwaters were constructed immediately west of the

original eight structures (Project TE-48) (Figure 3-3). The breakwaters have been

effective in holding sand on the eastern portion of the island, while the western

portion has continued to erode. Partial healing of this damage has taken place

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following passage of the storms, facilitated by normal longshore sediment transport

from the eastern part of the island (Figure 3-4). The source of this material has

been postulated to come from a large shoal that lies offshore of the eastern

breakwater field (Stone, et al., 2003). The apparent success of the breakwater field

at Raccoon Island led to suggestions that breakwaters should be seriously

considered elsewhere on the island.

Figure 3-3. Raccoon Island in 2007 following construction of second set of

breakwaters. (Photograph provided by NRCS).

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Figure 3-4. Aerial photograph of Raccoon Island taken in November 2008

following Hurricanes Gustav and Ike (Photograph provided by NRCS).

The PDT evaluated the potential effectiveness of an additional series of

breakwaters and a terminal groin on the western end of the existing breakwater

field using a series of models. The Steady State Spectral Wave (STWAVE) was used

to transform wave data from offshore locations to the surf zone. This information

was used in the Generalized Model for Simulating Shoreline Change (GENESIS) to

evaluate the impact of the structures on shoreline erosion. The coupled

STWAVE/GENESIS model was calibrated for Raccoon Island for a period preceding

the initial construction of the breakwaters and for the period following breakwater

construction.

The model platform was first used to assess the effectiveness of a 1,200-ft long

terminal groin at the western end of the island. A separate analysis was conducted

to assess the effectiveness of eight 300-ft long detached breakwaters along the

remaining western shoreline of the island. This analysis utilized the results of the

GENESIS modeling simulations of the existing breakwaters to extrapolate the

effects of the eight proposed breakwaters. A detailed discussion of the model efforts

is provided in the annex of Appendix L.

Based on the results of the two simulations, both series of structures are expected to

reduce shoreline erosion rates on the island. Furthermore, a preliminary cost119
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benefit analysis shows that the island strategy would be more cost-effective (i.e.

have a lower cost/acre) if it includes a terminal groin or additional breakwaters

(Table 3-2).

Table 3-2: Cost-Benefit Analysis of Raccoon Island

Island Strategya Project

Cost

Acres Cost/

Acre

Raccoon Island $54,400,000 301 $181, 000

Raccoon Island w/ Additional Breakwaters $58,100,000 326 $178,000

Raccoon Island w/ Terminal Groin $56,600,000 324 $175,000

aThe three island strategies include a beach, dune, and marsh component

Raccoon Island is the western-most island in the Isles Dernieres reach, with

nothing but open water to the west. The closest land is Pelican Island and Point au

Fer Island, 10 miles to the northwest across a complex of shoals east of the mouth of

Bayou du Large. These shoals and the large offshore sand body to the south of the

Isles Dernieres (Ship Shoal) receive large amounts of fine sediment (silt and clay)

from the outflow of the Atchafalaya River. This contribution is dependent on

tropical cyclone activity and winter storm cold front passage, with the latter

occurring almost weekly during the winter months. The fair weather dispersal

pattern for this sediment is to the west, towards the Cheniere Plain coast and

Texas. However, the aforementioned events re-suspend the fluvial sediment and redirect the river discharge onto the adjacent shelf to the south and east.

Measured sediment discharge from the Atchafalaya at Morgan City and the Wax

Lake Outlet varied from near zero to as much as 280 and 130 tons per day,

respectively. At peak (spring) flows the two sites recorded discharge rates of

300,000 and 200,000 cubic ft per second, respectively (Stone, et al., 2009). The same

authors indicate that surface sediment samples from Ship Shoal, 50 km southeast

of the Atchafalaya outlets, show accumulation of fluid mud. In situ instrumentation

and satellite imagery show that fluvial fine sediments debouched from the

Atchafalaya River, in a form of fluid mud, were accumulated onto the shoal in the

wake of storms (ibid., p. 90). The sediment that moves off of Raccoon Island to the

west is simply lost to the shoals and perhaps buried by the mud stream from the

Atchafalaya, so a terminal groin on Raccoon Island will not starve an island in an

adjacent reach.

LDWF values Raccoon Island very highly because it is the largest pelican rookery in

Louisiana, is critical habitat for piping plover, and is frequented by other

threatened and endangered species. The proposed conceptual restoration footprint

(beach, dune, and marsh) was shown covering some existing island habitat. The

PDT concluded that the footprint should be shifted gulfward and reconfigured to

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avoid the existing marsh and rookery. In addition, sand should be placed between

the breakwaters and the beach to act as a feeder for the downdrift beach.

The measures that were carried forward for Raccoon Island include segmented

breakwaters, a terminal groin at the west end of the island (to retard sand loss into

Caillou Bay), dune restoration, marsh creation, beach restoration, sand fencing,

vegetative plantings, and herbivory control. Sand fencing was considered to be a

necessary accompaniment to any beach and dune restoration effort. It was obvious,

from observations, that the most effective fencing installations were multiple rows,

oriented parallel to the shoreline.

3.2.3.3.2 Whiskey Island

Caillou Boca, which is a deep channel between Whiskey Island and the mainland,

presents a unique challenge for the restoration efforts. The channel will prevent

island roll-over because overwashed sediments will be carried away by the channel

and will be lost from the system. This will make it difficult to maintain the width of

the islands marsh component. Since the island is considered a valuable wildlife

habitat (Isles Dernieres Barrier Islands Wildlife Refuge) and the LDWF is

reestablishing a pelican rookery on the island, maintaining adequate areas of

healthy beach, dune, and marsh is particularly important. The PDT concluded that

the restoration template should be positioned to avoid the existing marsh and the

associated mangrove stands to protect existing sensitive habitats.

CWPPRA project TE50 (Whiskey Island Back Barrier Marsh Creation) was

completed in September 2009. The LDWF is interested in protecting the new marsh

with a combination of beach and dune restoration and construction of a field of

segmented breakwaters, similar to those on Raccoon Island. Based on this input,

the PDT undertook a modeling effort to determine the efficacy of a segmented

breakwater field in protecting the beach that fronts the marsh area.

In conjunction with the GENESIS modeling effort used to assess the breakwaters

and terminal groin on Raccoon Island, the effectiveness of segmented breakwaters

placed off Whiskey Island was evaluated (Appendix L). The modeling results

indicated that the rate of shoreline erosion would be reduced by the structures.

However, a preliminary cost-benefit analysis indicated that the additional benefits

provided by the breakwaters could not be justified by the additional costs associated

with their construction (Table 3-3). Since the breakwaters considerably increased

the cost/acre, they were eliminated as a possible measure for Whiskey Island.

Terminal groins were also eliminated because they could potentially cutoff sediment

supply to Raccoon Island.

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Table 3-3: Cost-Benefit Analysis of Whiskey Island

Island Strategya Project Cost Acres Cost/Acre

Whiskey w/out Breakwaters $63,520,000 474 $134,000

Whiskey w/Breakwaters $88,300,000 544 $162,000

aBoth island strategies include a beach, dune, and marsh component

The measures that were carried forward for Whiskey Island include dune

restoration, marsh creation, beach restoration, sand fencing, vegetative plantings,

and herbivory control.

3.2.3.3.3 Trinity/East Island

East Island had been part of Trinity Island until 1974, when Hurricane Carmen

breached the island. Subsequent hurricanes widened the breach, which was named

New Cut. East Island has had one CWPPRA project (TE20), involving dune

enhancement and marsh creation. The project, Isles Dernieres Restoration East

Island, was combined with the preceding project (TE24) and both were completed on

the same timetable in 1998, with the revegetation effort concluding in 1999.

Littoral drift carried sand from the East Island project into New Cut. In addition, a

separate CWPPRA project, TE37, New Cut Dune and Marsh Restoration, was

developed to close the breach, and it was completed in 2007. That project created a

dune platform that matched the elevation of the adjacent platforms on East and

Trinity Islands, thus restoring Trinity Island to a semblance of its original linear

dimension.

The PDT concluded that the combination of beach, dune, and marsh restoration was

the best mechanism for protecting most of Trinity/East Island, but again

emphasized shifting the template Gulfward. The team stressed the importance of

marsh creation behind the newly-restored Trinity/East Island, to buffer the north

side of the island from wind-driven waves moving across Terrebonne Bay from the

north and northeast and help anchor the beach/dune system by providing a marsh

platform to hold overwash sand and retain it in the island profile.

Sand fencing has been a structure used at previous projects on Trinity/East Island.

Some fences were continuous, shore-parallel installations and some were short

sections, sited at 45 degrees to the shoreline alignment. Observation of these

reinforced the consensus that sand fencing should be an integral component to all

beach/dune projects and that it should be aligned parallel to the shoreline.

The measures that were carried forward for Trinity and East Islands include dune

restoration, marsh creation, beach restoration, sand fencing, and vegetative

planting. Although there is currently a canal on Trinity Island that would benefit

from a plug in the near-term, the restoration of the dune, beach, and marsh will

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provide a longer-lasting solution. Based on the results of the modeling efforts for

Whiskey Island, it was inferred that segmented breakwaters would not be costeffective on Trinity or East Island and therefore were eliminated from further

consideration. Terminal groins were also eliminated because they could potentially

cutoff sediment supply to Whiskey and Raccoon Island.

3.2.3.3.4 Wine Island

Historically, Wine Island was the easternmost island of the Isles Dernieres. It was

approximately three miles in length, and located across the mouth of the present

Wine Island/Cat Island Pass (Penland, et al., 2005). By the mid-20th Century the

island had migrated north and slowly disappeared. What is now called Wine Island

is a rock-stabilized dredge material disposal site, associated with the Houma

Navigation Canal (Channel). The Terrebonne Parish Council has requested

restoration of Wine Island in a resolution, adopted on 25 March 2009. It is obvious

from the wording of the resolution and previous correspondence from the Parish

President that the desire is to reduce the width of the pass by restoring Wine Island

to some previous dimension and location. Wine Island is also an active seabird

rookery, thus its preservation and improvement is important to LDWF.

The island was once surrounded by a boulder revetment, constructed in 1991 to

hold discharged material from dredging the HNC. The island is no longer contained

within the revetment. Its area has been reduced and its footprint has migrated

north such that about one third of it presently lies outside the subcircular ring of

rocks.

The team suggested two courses of action regarding Wine Island. The first involves

restoring the island within the boulder revetment, through beneficial use of

sediment dredged from the HNC. The second would be a much more ambitious

project, involving development of a restoration template anchored at the present

island location and extending to the adjacent shoal, referred to locally as the

Monkey Bar, to create a larger island, more in accord with the request from

Terrebonne Parish.

If the former course of action is followed, the restoration template would overlay the

existing subcircular revetment, which would serve as containment for the dredged

sediment. The small area of the island precludes attempting differentiation of

beach, dune, and marsh. Rather, the fill material would be graded and planted

with dune-stabilizing vegetation, to prolong sediment retention and provide

additional habitat for the birds.

If the latter course of action is selected, the restoration template would overlay the

existing island, the subcircular revetment, and extend to the west to encompass the

shoal. Developing the template will be dependent on a modeling effort based on

detailed bathymetry of the shoal and selection of a method to contain the fill

material. The exposed nature of the shoal appears to preclude use of earthen dikes

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for containment and, without the foundation of an existing beach and dune system,

unconfined pumping of beach sediment appears to be out of reach physically and

financially. This situation may change if the sediment source is maintenance

dredging and/or realignment of the HNC (Rosati, 2008).

The measures that were carried forward for Wine Island include repair of the

existing continuous revetment, dune restoration, marsh creation, beach restoration,

sand fencing, vegetative plantings, and herbivory control.

3.2.3.3.5 Timbalier Island

Timbalier Island has had two CWPPRA projects. The first one, TE18, involved

installation of sections of sand fencing (greater than a mile in total) in different

areas in 1995, and planting dune-stabilizing vegetation in selected areas in 1996.

The second project, TE40, offset the ongoing erosion of the east end of the island by

restoring more than two miles of beach and dune, installing more sand fencing,

planting dune-stabilizing vegetation, and building additional marsh. A second

component of TE40 was the addition of sediment to the nearshore to facilitate

longshore transport without eroding the restored beach.

The large breach on Timbalier Island presents a compelling argument in favor of

canal backfilling. There is sufficient tidal exchange occurring through the canal to

prevent sediment accumulation. Therefore, the PDT concluded that the proposed

restoration template, combining beach, dune, and marsh creation, was the best

overall solution to restoring Timbalier Island. To be effective, it must include

closure of the existing breach as well as backfilling as many of the canals as

possible. This latter activity may be difficult, because the canals are apparently

routinely used to service isolated petroleum production facilities and wells, based on

evidence of recent dredging. The PDT noted the elevation of the dune field created

by CWPPRA project TE-40, and recommended that new dune construction match it.

It was also noted that the eastern third of the TE-40 projects dune fencing is now

offshore, indicating that the east end of the island has continued to erode. The

proposed restoration template includes restoration of that part of the island.

The measures that were carried forward for Timbalier Island include dune

restoration, marsh creation, beach restoration, sand fencing, vegetative plantings,

and herbivory control. Based on the results of the modeling efforts for Whiskey

Island, it was inferred that segmented breakwaters would not be cost-effective on

Timbalier Island and therefore were eliminated from further consideration.

During field visits to Timbalier Island, the PDT observed evidence of sediment

accumulation at the western end of the island. Therefore, it was determined that a

terminal groin would not be needed on the island.

3.2.3.3.6 East Timbalier Island

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East Timbalier Island is the site of an oil and gas production and processing facility.

Much of the island was in imminent danger of disappearing when its two CWPPRA

projects were implemented. The projects are East Timbalier Island Sediment

Restoration, Phases 1 and 2, TE25 and TE30, respectively. The combined projects

created a wide beach and dune system, backed by a wide marsh on the western,

large portion of the island. The restored areas were vegetated and sand fencing was

installed. Unfortunately, the goal of rejoining the two ends of East Timbalier Island

was not met. A rock rubble revetment parallels the shoreline of both parts of East

Timbalier Island, on the order of 500 to 1,000 ft offshore. The distance indicates the

northward movement of the island, in the time since the revetment was placed on

the shoreline. Project TE30 also constructed a similar revetment along the beach

face to protect the restored beach and dune.

The proposed island restoration template includes the presently submerged eastern

half of the island, which was initially proposed as part of the CWPPRA project TE30, but was not completed. Should the east-west dimension of the island be

restored, it was suggested that a terminal groin be installed at the east end of the

fill, to prevent it from migrating into Timbalier Bay. However, a terminal groin was

later eliminated because of the potential impacts the structure could have on

sediment supply to Timbalier Island.

The PDT discussed previous attempts to stabilize East Timbalier Island. Several

series of boulder revetments were place on the shoreline in the past. The gulfside

rocks are now several hundred ft offshore, and the rock placed along the north

shoreline is apparently buried within the island. Due to the lack of effectiveness of

the hard structures that have been implemented for past CWPPRA projects, the

PDT determined that breakwaters would not an effective measure for East

Timbalier and thus eliminated them from future consideration.

The measures that were carried forward for East Timbalier Island include dune

restoration, marsh creation, beach restoration, sand fencing, vegetative plantings,

and herbivory control.

3.2.3.3.7 Results

Table 3-4 summarizes the island strategies that were carried forward for each

island. These island strategies will be combined and paired with various

combinations of borrow areas to form alternatives.

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Table 3-4: Summary of potential island strategiesa

Description of Island Strategy Raccoon Whiskey Trinity East Wine Timbalier

East

Timbalier

Beach / Dune / Marshb Yes Yes Yes Yes Yes Yes YesBeach / Dune / Marsh w/ SegmentedBreakwatersb Yes No No No No No NoBeach / Dune / Marsh w/ Terminal Groinb Yes No No No No No NoMarsh Creation w/ Continuous Revetmentc No No No No Yes No No

a Yes indicates the island strategy was carried forward; No indicates the island strategy was screened outb Combination includes sand fencing, vegetation planting, and herbivory controlc Combination includes vegetation planting and herbivory control

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3.2.4 Value Engineering Analysis

In May 2009, Value Management Strategies (VMS) conducted a Value Engineering

(VE) analysis. The results of the analysis were summarized in a VE report (VMS,

2009). The VE study included an evaluation of not only the LCA TBBSR Study, but

also the Houma Navigation Lock Operations Plan and Convey Atchafalaya River

Water to Northern Terrebonne Marshes studies. Specific to LCA TBBSR Study,

forty-five ideas were put forth, with 17 designated as Alternative Concepts, and

nine of those identified as Key Recommendations.

Six key VE-recommended concepts involved soft-structural solutions. One was

directly applicable and it had already been incorporated into plan formulation:

consider coastal geomorphic processes for sediment placement. Such consideration

is common practice in barrier island restoration design. A coastal processes analysis

was conducted to define the minimum island dimensions to restore the

geomorphologic form and ecologic function of a barrier island. This analysis

accounted for both longshore and cross shore sediment transport.

A second key VE-concept involved recycling sand from the downdrift/down gradient

end of an island to the updrift end. Recognition of the sand-starved status of

Coastal Louisiana resulted in development of a hydrogeomorphic planning objective

of the LCA 2004 Report, specifically to import sediment from sources outside of the

estuarine basins (i.e., beyond the depth of closure) (LCA, 2004). Therefore the

borrow areas for island restoration shall be located seaward of the depth of closure

defined as the offshore extent of the active beach face. This second concept is not

consistent with this planning objective.

A third key VE-concept called for excavation of a series of inverted breakwaters

(shore-parallel pits that reduce wave energy as waves pass across them). Sediment

inshore of the depth of closure must be considered as part of the sand budget for

that particular reach, and conservation of that resource is essential in a sandstarved system, such as the Louisiana coast. Excavations inshore of the depth of

closure have the potential to become sinks that accumulate sediment that is

normally part of the longshore or cross shore transport system. Of concern with

this concept is conservation of the sand resources and avoidance of interference with

coastal processes from excavating these resources for island restoration.

Two other VE-concepts involved hard structures, one a permanent dredge discharge

pipe from Ship Shoal to East Timbalier Island and the other installation of a sandfilled geotextile tube or a boulder core beneath the dune, to fix an island in position.

Alternative measures similar to these concepts were considered such as continuous

rock revetments; however, these measures were screened out in the initial screening

as not meeting the planning criteria (Section 3.2.3.1).

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The sixth VE-concept was to abandon the existing islands and construct a new

island reach to the north. This concept is inconsistent with the LCA 2004 Report

that defined the Study as restoring the Terrebonne Basin barrier islands through

simulating historical conditions by enlarging the barrier islands (width and dune

crest) and reducing the current number of breaches. Further it is inconsistent with

the planning objectives developed for the Study (Section 2.3).

The remaining three key VE-concepts were policy suggestions beyond the scope of

this Study: establishment of a permanent trust fund for island renourishment,

define the Study in terms of sustainability in year 2100, and task the Mineral

Management Service with deciding on offshore sediment allocations and locating

new, untapped sources of fill material.

3.2.5 Screening / Evaluation of Borrow Areas

Khalil et al. (2010) mapped numerous potential sediment borrow areas along the

Louisiana Gulf coast, from South Pass west to Sabine Pass. Six large-volume areas

were delineated off the Terrebonne Basin Barrier Islands (Figure 3-5). Three of

these are on the Outer Continental Shelf (OCS) and three are in State waters,

closer to shore. The latter included a group of five small borrow areas associated

with a Timbalier Island project, three north of the island, in the bay, and two to the

south.

The borrow area map developed by Khalil et al. (2010) was used as a starting point

for the PDTs borrow area search effort. Their tabular compilation included the

location of the borrow area, estimated volume of available fill material, volume of

material already dredged from the borrow area, and pertinent geotechnical and

geophysical references.

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Figure 3-5. Terrebonne Basin borrow areas (Khalil et al., 2010)

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3.2.5.1 Borrow Area Characteristics and Screening Criteria

The PDT used a combination of physical, geographic, and socioeconomic

characteristics to evaluate the borrow areas presented in Figure 3-5. The primary

criterion that was considered in the evaluation is discussed below.

3.2.5.1.1 Location Relative to Depth of Closure

The depth of closure represents the offshore extent of the active beach face, thus

sediment inshore of it must be considered as part of the sand budget for that

particular reach, and conservation of that resource is essential in a sand-starved

system, such as the Louisiana coast. Excavations inshore of the depth of closure

become sinks that accumulate sediment that is normally part of the longshore/onoff-shore transport system. Of concern here is conservation of the sand resources

and avoidance of interference with coastal processes from excavating these

resources for island restoration. Recognition of the sand-starved status of Coastal

Louisiana resulted in development of a hydrogeomorphic planning objective of the

LCA 2004 Report, specifically to import sediment from sources outside of the

estuarine basins (i.e., beyond the depth of closure) (LCA, 2004). Therefore the

borrow areas shall be located seaward of the depth of closure which was defined to

be equal to -10.5 ft NAVD 88.

3.2.5.1.2 Borrow Area Geotechnical and Geophysical Data

The sediment particle size ranges and distributions should match the characteristic

of the beach and dune where it will be placed. In the case of marsh material, there

should be variability in particle size to match the existing marsh environment. The

sediment should be compatible with the sediment at the fill placement site to avoid

accelerated loss of sand and changes in beach face morphology. To maximize

efficiency of the excavation process, the core data and seismic profiles should

indicate adequate stratum thickness for efficient mining. If the strata are too thin,

the excavation process can create a blend of material that may be compatible with

the native sediment at the fill placement site, but that must be determined from the

data, and not left to chance.

3.2.5.1.3 Borrow Area Volumes

The sediment volume must equal or exceed the estimate of volume needed to

complete the Study.

3.2.5.1.4 Cultural Resources/Petroleum Infrastructure Clearance

Cultural resources can be significant constraints. The locations of potential sites,

possibly representing either historic shipwrecks or prehistoric sites, and pipelines

must be avoided. Remote-sensing surveys are a requisite for consultation with the

State Historic Preservation Office (SHPO) and other involved agencies. Use of

borrow areas must often be approved or cleared by the Minerals Management

Service (MMS) or the LDNR.

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3.2.5.1.5 Technical Difficulty

Borrow site location factors, such as water depth and distance to disposal site, can

dictate use of hopper or cutterhead dredge. Depending on the alternative, different

measures are required to transfer the dredged material to the disposal site(s). The

issue involves double handling of dredged material. If the disposal site depth is

inadequate to accommodate the draft of a hopper dredge it may require offshore

dumping and re-dredging by cutterhead or offshore booster pumps to move material

ashore. Inadequate depth at the borrow area to accommodate a hopper dredge may

require use of a cutterhead dredge. The latter type is less seaworthy than the

former, thus introducing heightened concern about weather-related production

interruptions.

3.2.5.1.6 Navigational Features

The HNC, its channel across Terrebonne Bay, and the Bayou Grand Caillou Safety

Fairway are Federally-designated waterways in which interference with navigation

is an issue. Constraining use of such channels with fill material, structures, or

equipment, even temporarily, requires advance notice and authorization from the

USACE.

3.2.5.1.7 Mining Impacts

Offshore shoals, bypassing bars, and similar bodies interact with the waves that

pass across them. Waves can be attenuated and their directions changed, so that

the wave energy that impacts a nearby shoreline is changed. Depending on the

wave length, height, and direction, the changes can be beneficial or detrimental,

resulting in either accretion or erosion of the shoreline. The results of wave

refraction modeling, based on wind and wave direction and intensity data, must be

carefully analyzed to ensure that excavation of the borrow area does not result in

detrimental changes to the shoreline or nearby passes.

3.2.5.2 Initial Screening

The first-level screening was finalized during the PDT meeting on 11 August 2009.

The PDT Team had previous discussions with CPRA staff regarding potential

borrow areas and their supporting information, and this was incorporated into the

screening process. The first-level screening criterion that was applied to the borrow

areas identified in Figure 3-5 was location. Using this criterion, the Timbalier

Island Dune and Marsh Restoration (TE-40) borrow areas 9a through 9d were

eliminated because all four fell within the depth of closure. Note that Borrow Area

9e was retained.

Table 3-5 presents information about the potential borrow areas that passed the

first level of screening. The locations of the borrow areas are depicted in Figure 3-6.

It should be noted that the numbers assigned to each area differ from those

presented in the Figure 3-5 because several previously unnumbered areas were

identified and added to the evaluation.

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Table 3-5: First level borrow area screening

I

D Location Sediment Type Applicabilit

y

Thickness

of

Sediment

Source (ft)

Sediment

Composition

Availabl

e

Volume

(mcy)

Cultural Resources

1 Whiskey Island TE-50 Area 1 Mixed, silt, clay (overburden) Marsh NA NA NA NA Sand Beach/Dune 0.8  2.4 NA NA NA2 Whiskey Island TE-50 Area 2 (subarea 2a) Mixed, silt, clay (overburden) Marsh 8-9.5

6-47% sand;13.5-66.5% Silt;20.7-83.4% clay

0.29a

Chirp. magnetic, and side scansonar surveys (Ocean Surveys,2006)

Sand Beach/Dune 2.5-7.6 90% sand 0.79b

3

Whiskey Island TE-50Area 3 (subarea 3a)

Mixed, silt, clay (overburden) Marsh 3.5-17.4

20% sand; 30-49.7% silt; 27.4-68.7% clay

7.97 Chirp, magnetic, and side scan

sonar surveys(Ocean Surveys, 2006) Sand Beach/Dune 2.5-14 80% Sand 4.72

Whiskey Island TE-50Area 3 (subarea 3b)

Mixed, silt, clay (overburden) Marsh 7.5 6-47% Sand 0.73 NA

Sand Beach/Dune 2.7-6.4 80% Sand 1.13

Whiskey Island TE-50Area 3 (subarea 3c)

Mixed, silt, clay (overburden) Marsh 8 22% Sand 0.18 NA

Sand Beach/Dune 8.5 85% Sand 0.20

4 New Cut TE-37 Area Sand Beach/Dune 6 - 2.5c Vibracore & Magnetic Surveys5 Raccoon Island TE-48 Mixed sand, silt, clay Marsh 10-20 16.5-24.6% above #200 sieve 2.4d Remote sensing side scan & mag surveys (Goodwin, 2008)6 South Pelto Blocks 12 & 13 Sand Beach/Dune 13-20 <5% silt 21.3e Seismic, sonar, and mag surveys (USEPA, 2003b)7

Ship Shoal Block 88 Sand Beach/Dune 10-19 <5% silt 17.3

Seismic, sonar, and magsurveys (USEPA, 2003a);Echosounder & vibracoresurveys & sediment samplinganalysis (STE, 2004)

Ship Shoal Blocks 84,85, 98, & 99 Sand Beach/Dune 8-12 <5% Silt 47.5 Seismic, sonar, and mag surveys (USEPA, 2003a)

8 Western Ship Shoal Blocks 84, 85, 98, &99 Sand Beach/Dune 13 NA 124f Not Available9 Cat Island Pass Sand Beach/Dune 5-10 Silty sand 6.6g Not Availablea Excludes a volume of 2.76 mcy of overburden material estimated for Whiskey Island TE-50 Project

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b Excludes a volume of 0.36 mcy of dune material estimated for Whiskey Island TE-50 Projectc Available volume based upon personal communication with CPRA, Aug 2009d Excludes a volume of 1mcy estimated for Raccoon Island TE-48 Projecte Excludes a volume of 7mcy estimated for Caminada Headland Restoration Projectf Estimates based on Results of the Western Ship Shoal Geophysical Survey: Evaluation of Sand Available for Coastal Restoration Mar

2009

g Estimates based on September 2003 geologic profiles obtained from USACE through personal communication

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Figure 3-6. First level screening: Borrow area locations

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3.2.5.3 Final Screening

The process of screening potential borrow areas continued in September and

October 2009, reducing them down to those that provide the requisite volume of

sediment, have existing geotechnical and geophysical survey data, and cultural

resource data needed to develop conceptual excavation plans. A thorough review of

the existing geophysical and geotechnical data indicated that a sufficient volume of

compatible sediments was available in the existing borrow areas to construct the

LCA TBBSR Study at a feasibility level. Therefore, additional geophysical and/or

geotechnical surveys were not conducted during this investigation.

The potential borrow areas that were eliminated during this screening were:

 Timbalier Island TE-40 Borrow Area 9e was eliminated because a portion of

it was landward of the depth of closure.

 Western Ship Shoal (Blocks 84, 85, 98, & 99), Borrow Area 4 was eliminated

because it lacked detailed geophysical surveys and a cultural resource

investigation.

 HNC Channel was eliminated because of the risk and uncertainty of relying

on a sediment source that is under the control of interests with a requirement

to maintain navigability without undue delay, particularly following storm

events that could cause shoaling. Should emergency dredging be required,

there would not be sufficient sediment available for construction. In

addition, geotechnical and cultural resources data are only available for the

portions of the channel that are periodically maintenance-dredged, not

necessarily the channel offshore from Cat Island Pass, the logical portion to

serve as a borrow area because it is seaward of the depth of closure. There

are also restrictions on width of dredge cut, one cannot dredge outside of the

designated channel without an Environmental Assessment, and cut depth,

one cannot dredge deeper than the authorized channel depth. Taken

together, these constraints and restrictions were felt to introduce too much

risk to retain the HNC as a viable borrow area. Because of its location, the

PDT Team felt that the HNC should be retained as an alternative borrow

area to be considered in PED if the cultural resource investigation is

completed and the timing of its use is compatible with the navigation

interests as determined by USACE.

 Whiskey Island TE-50 Borrow Area 1 was eliminated because it lacked

geotechnical and borrow area volume information, detailed geophysical

surveys, and a cultural resource investigation.

 Whiskey Island TE-50 Borrow Area 2 was also eliminated as a potential

sediment source. During the course of planning for the TE-50 project, T.

Baker Smith and Moffatt & Nichol refined the designs of Borrow Areas 2 and

3, designating one subarea in 2 (2a) and three subareas in 3 (3a, 3b, and 3c).

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They recommended use of Subarea 2a. Since the TE-50 project has already

utilized both the overburden and sand resource volumes in Subarea 2a,

Borrow Area 2 was eliminated from further consideration (TBS and M&N,

2007).

 The PDT further refined Whiskey Island TE-50 Area 3. Subareas 3b and 3c

were eliminated because detailed geophysical surveys were not conducted

and they lacked cultural resource investigations. The Borrow Area 3 outline

was reduced to depict only the outline of Subarea 3a, thus Figure 3-7 which

presents the final borrow area screening map depicts a smaller Borrow Area

3.

In a similar manner, the outline of the South Pelto borrow area was reduced to

represent the actual outline of the combined borrow areas identified in Blocks 12

and 13. Results of the final screening effort are summarized in Table 3-6 and Figure

3-7.

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Table 3-6: Final level borrow area screening

ID Location Sediment Type Applicability

Thickness of

Sediment

Source (ft)

Sediment

Composition

Available

Volume

(mcy)

Cultural Resources Survey

Data

3 Whiskey Island TE-50 Area 3 (subarea 3a) Mixed, silt, clay (overburden) Marsh 3.5-17.4

20% sand; 30-49.7% silt; 27.4-68.7% clay

7.97 Chirp, magnetic, and side scan

sonar surveys(Ocean Surveys, 2006) Sand Beach/Dune 2.5-14 80% Sand 4.72

4 New Cut TE-37 Area Sand Beach/Dune 6 - 2.5a Vibracore & Magnetic Surveys5 Raccoon Island TE-48 Mixed sand, silt, clay Marsh 10-20 16.5-24.6% above #200 sieve 2.4b Remote sensing side scan & mag surveys (Goodwin, 2008)6 South Pelto Blocks 12 & 13 Sand Beach/Dune 13-20 <5% silt 21.3c Seismic, sonar, and mag surveys (USEPA, 2003b)7

Ship Shoal Block 88 Sand Beach/Dune 10-19 <5% silt 17.3

Seismic, sonar, and magsurveys (USEPA, 2003a);Echosounder & vibracoresurveys & sediment samplinganalysis (STE, 2004)

Ship Shoal Blocks 84,85, 98, & 99 Sand Beach/Dune 8-12 <5% Silt 47.5 Seismic, sonar, and mag surveys (USEPA, 2003a)

a Available volume based upon personal communication with CPRA, Aug 2009b Excludes a volume of 1mcy estimated for Raccoon Island TE-48 Projectc Excludes a volume of 7mcy estimated for Caminada Headland Restoration Project

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Figure 3-7. Final level screening: Borrow area locations

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3.2.5.4 Resulting Borrow Areas

The initially-proposed source of borrow sand for beach and dune restoration was

Ship Shoal, an elongate sand body in the Gulf, located 20 to more than 40 miles

west of Belle Pass and four to ten miles south of the Isles Dernieres. It is

approximately 31 miles long and 7 miles wide, lying in a water depth of 9 to 30 ft.

Ship Shoal is ideal for use in restoring the Terrebonne Basin barrier islands since

its grain size is equal to or greater than the sand found on the islands. Coarser

grain sand is more resistant to erosion. Ship Shoal is the nearest, accessible sand

source that contains a sufficient quantity of sand of appropriate quality to match

the native sand found on the islands and achieve the Study goals. Screened Borrow

Areas 6 and 7 depicted in Figure 3-7 are both located on Ship Shoal. Several closer

sand sources, previously identified for other CWPPRA project use, were proffered to

the PDT, and they were investigated. The two most-promising are Subarea 3a of

the Whiskey Island TE-50 Borrow Area 3 and the New Cut TE-37 Borrow Area 4.

The proposed sources of borrow sediments for marsh creation and restoration have

also been identified. Nearshore resources seaward of the depth of closure will be

utilized to provide mixed sediments consisting of fine sand, silts, and clays

compatible with the existing island framework. The two marsh sediment borrow

areas are the Raccoon Island TE-48 Borrow Area 5 and the overburden stratum on

Subarea 3a of the Whiskey Island TE-50 Borrow Area 3.

Two previously-considered borrow areas will be revisited during the PED phase of

the Study. If there are sufficient time and funding, the geophysical, geotechnical,

and cultural resources studies required for Whiskey Island TE-50 Borrow Area 1

will be undertaken. Should the results prove positive the borrow area will be

incorporated into the project design. In a like manner, potential beneficial use of

sediment from the entrance channel for the Houma Navigation Canal will be

explored through the Navigation Branch of the New Orleans District. As described

in Section 3.2.5.3, it will be necessary to carry out further cultural resources and

geotechnical investigations, but the proximity of the HNC to both Trinity and

Timbalier Islands makes it a cost-effective alternative.

3.3 PRELIMINARY ALTERNATIVE PLANS

This section summarizes the development and evaluation of the preliminary

alternative plans. For more details on each alternative, refer to the Engineering

Appendix, (Appendix L).

3.3.1 Development of Alternative Plans

An alternative is defined as a combination of island strategies and borrow areas.

The features that were carried forward from the third level of screening include the

following:

 Raccoon Island: Beach/Dune/Marsh

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 Raccoon Island: Beach/Dune/Marsh w/ Segmented Breakwaters

 Raccoon Island: Beach/Dune/Marsh w/ Terminal Groin

 Whiskey Island: Beach/Dune/Marsh

 Trinity Island: Beach/Dune/Marsh

 East Island: Beach/Dune/Marsh

 Wine Island: Marsh Creation w/Continuous Revetments

 Timbalier Island: Beach/Dune/Marsh

 East Island: Beach/Dune/Marsh

These island strategies were selected because they would be consistent with the

Environmental Operating Principles (EOPs), present the fewest constraints, and

would be synergistic with other existing and authorized projects on the islands.

The borrow areas that were carried forward from the third level of screening include

the following:

 Whiskey Island TE-50  Area 3a (marsh material)

 New Cut TE-37 (beach/dune material)

 Raccoon Island TE-48 (marsh material)

 South Pelto (beach/dune material)

 Ship Shoal (beach/dune material)

The above mentioned borrow areas were selected because they were outside the

depth of closure, had adequate capacity of compatible material, and included

cultural resource survey information.

Initially, each of the island strategies was combined with each of the marsh and

beach/dune borrow areas. However, this produced a cumbersome number of

alternatives to be analyzed (over 4 million). In an effort to reduce the number of

alternatives to a more manageable number, the PDT evaluated the location and

capacity of each borrow and paired the most appropriate borrow areas to each

measure.

3.3.2 Description of Alternative Plans

Five restoration plans, denoted as Plans A through E, were developed as part of

plan formulation. The plans are discussed in the following sections. An additional

option was derived for Wine Island that included placing beach compatible sand

within the existing rock revetment locally known as the Wine Island Ring. Two

additional options were derived for Raccoon Island including the construction of

eight additional breakwaters (BW) or construction of a terminal groin (TG).

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3.3.2.1 No Action Plan (Plan A) - Future Without Project Conditions

Plan A represents the No Action plan, that is, no sediment is imported to restore

the islands components (i.e. beach, dune and marsh) and no restoration actions are

taken. The No Action plan is synonymous with Future Without Project (FWOP)

conditions. This plan as identified as Alternative 1 in subsequent sections of the

report.

3.3.2.2 Minimum Design Plan (Plan B)

The restoration template for Plan B provides for the minimal geomorphologic form

and ecologic function on each island and retains this form and function after being

subjected to a number of design storms.

3.3.2.2.1 Geomorphologic Form and Ecologic Function

The barrier islands in the Study Area are the remains of an abandoned Mississippi

River Delta; and their degradation is the result of anthropogenic activities and

episodic storm impacts, in combination with natural deltaic processes. The barrier

islands are typically low lying and comprised of three physical features, the beach,

dune, and back barrier marsh. They act as a buffer to reduce the full force and

effects of wave action, saltwater intrusion, storm surge, and tidal currents on

associated estuaries and wetlands. To restore their geomorphologic form and

provide this buffer involves reinforcing the shoreline through beach and dune

restoration. In addition, it includes providing a marsh platform to capture

overwash sediments during episodic events; sediment that would otherwise be

carried into back bay areas to form shoals or be lost into deeper waters. The marsh

also serves as a roll over platform as the islands migrate landward.

Restoration of ecologic function of the barrier islands includes vegetating both the

restored dunes and back barrier marsh platforms with native plants, to provide

wetland habitat for a diverse number of plant and animal species and to help retain

sediment. This approach is supported by the Wetland Value Assessment (WVA),

which has been chosen as the model to evaluate the ecosystem restoration project

benefits. The WVA states that the key habitat components, dune, supratidal

(beach), and intertidal (marsh), combine to provide the optimum metric by which

the islands should be compared (CWPPRA, 2002).

In order to provide geomorphologic form and ecologic function, the beach, dune, and

marsh components must exhibit certain dimensions. These dimensions were

defined through analysis of historical planforms and elevations. Furthermore,

these dimensions must be maintained after being subjected to selected design

storms. The design storms that were used in template development included a

hypothetical 50-year storm as well as the varying intensities, durations, and

approach paths of Hurricanes Katrina and Rita, which occurred in 2005, and

Hurricanes Gustav and Ike, which occurred in 2008. The development of the

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template components (i.e. beach, dune, and marsh) is discussed in the following

sections.

SBEACH, a widely accepted cross-shore sediment transport model, was utilized for

predicting storm-induced beach and dune erosion. The models use is considered

standard practice both in the United States and internationally as evidenced by the

many documented applications in professional journals and conference proceedings.

The assumptions utilized in the modeling program along with verification of use of

the model are presented in Appendix L.

3.3.2.2.2 Beach and Dune Component

Based on historical natural beach and dune elevations, and SBEACH simulations

that were performed on an array of various restoration plans to examine storminduced beach and dune erosion, the following design criteria for Plan B were

derived:

 Gulf-side beach width: 250 ft,

 Beach elevation: 3.8 ft NAVD 88,

 Dune width:100 ft

 Dune elevation: 6.0 ft NAVD 88, and

 Bay-side beach width: 100 ft.

Louisianas barrier islands have poorly developed sand dunes as a result of a

limited amount of aeolian transported sand and the high frequency of overwash by

storms. The SBEACH dune elevations resulting from a 50-year storm simulation

on a 6-ft dune (Table 2-2 in Annex L-3) fell within the range of values reported by

the Louisiana Geological Survey (LGS 1989 and 1995) in Coastal Sand Dunes of

Louisiana, an Inventory. LGS reported dune elevations ranging from 2 to 5 ft

NGVD88 for Timbalier and East Timbalier and 0.7 to 5 ft NGVD88 for the Isles

Dernieres.

3.3.2.2.3 Marsh Component

The marsh serves as a roll over platform as the islands migrate landward. Based on

the post storm observations from the recent historic storms, there is ample evidence

that the back barrier marsh width needs to be on the order of 1,000 ft to capture

overwash sediments during episodic events; sediment that would otherwise be

carried into back bay areas to form shoals or be lost into deeper waters. Cross-shore

sediment transport models, e.g., SBEACH, tend to underestimate the extent of

overwash. Examination of vertical aerial photographs of the Texas coast, made

following Hurricane Ike, show areas of overwash extending from 800 to 1,300 ft

inland (Ewing, 2009). An extensive study of overwash on the Caminada-Moreau

Headland by Ritchie and Penland found that, for much of the low shoreline,

overwash penetrated from 700 to more than 1,000 ft beyond the beach (Ritchie and

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Penland, 1989). Examination of the aerial photographs in Williams, et al. (1992)

show overwash areas extending to 1,300 ft on Timbalier Island and greater than

700 ft on East Island. Personal observations by various PDT members support

planning for a minimum marsh width of 1,000 ft. Therefore, 1,000 ft was defined as

the design criteria for the minimized restoration template for the marsh platform

width.

Based on similar Louisiana barrier island restoration plans, the average healthy

marsh elevation, defined as the target elevation for the marsh platform, is typically

within +/- 0.1 ft of Mean High Water (MHW). MHW for the Study area is

approximately 1.6 ft NAVD 88 and was defined as the design criteria for the

minimized design plan for the marsh platform elevation. Marsh fill compaction (a

combination of foundation settlement and fill consolidation) was compensated for in

each island design, as described and discussed in Appendix L.

3.3.2.3 Design Plan Scalars (Plans C through E)

Plans C through E are scalars of Plan B that incorporate incremental increases in

the scales of beach, dune and marsh planforms and elevations to provide plan

formulators the ability to determine the optimal increment for restoration of the

geomorphologic form and ecologic function of these islands. The optimal level of

restoration is defined as the best balance of environmental benefits (e.g., habitat

acres), constructability as constrained by available sediment volumes in identified

borrow sources, and cost effectiveness. Plan C provides for the minimal

geomorphologic form and ecologic function on each island along with 5 years of

additional protection from background erosion/land loss (i.e. advanced fill). Plan D

provides for the minimal geomorphologic form and ecologic function on each island

along with 10 years of advanced fill. Plan E provides for the minimal

geomorphologic form and ecologic function on each island along with 25 years of

advanced fill.

The habitat acres that will be created by each plan are provided in Table 3-7. The

table also identifies the borrow area that would be utilized for each plan.

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Table 3-7: Summary of Created Habitat Acres

Island Plan

Dune/

Supratidal

Area at TY1

(acre)

Intertidal

Habitat

at TY1

(acre)

Beach/Dune

Borrow

Area

Marsh

Borrow

Area

Raccoon

Plan A 51 184 Ship Shoal Raccoon TE-48

Plan B 271 235 Ship Shoal Raccoon TE-48

Plan C 341 237 Ship Shoal Raccoon TE-48

Plan D 520 122 Ship Shoal Raccoon TE-48

Plan E 751 39 Ship Shoal Raccoon TE-48

Plan B w/ BW 271 237 Ship Shoal Raccoon TE-48

Plan C w/ BW 342 239 Ship Shoal Raccoon TE-48

Plan D w/ BW 521 122 Ship Shoal Raccoon TE-48

Plan E w/ BW 752 39 Ship Shoal Raccoon TE-48

Plan B w/ TG 271 237 Ship Shoal Raccoon TE-48

Plan C w/ TG 341 238 Ship Shoal Raccoon TE-48

Plan D w/ TG 520 122 Ship Shoal Raccoon TE-48

Plan E w/ TG 751 38 Ship Shoal Raccoon TE-48

Whiskey

Plan A 377 443 Ship Shoal Whiskey Area 3a

Plan B 670 509 Ship Shoal Whiskey Area 3a

Plan C 895 377 Ship Shoal Whiskey Area 3a

Plan D 986 376 Ship Shoal Whiskey Area 3a

Plan E 1402 250 Ship Shoal Whiskey Area 3a

Trinity

Plan A 238 326 South Pelto Whiskey Area 3a

Plan B 464 569 South Pelto Whiskey Area 3a

Plan C 585 564 South Pelto Whiskey Area 3a

Plan D 1198 72 South Pelto Whiskey Area 3a

Plan E 1523 67 South Pelto Whiskey Area 3a

East

Plan A 199 59 South Pelto Whiskey Area 3a

Plan B 318 362 South Pelto Whiskey Area 3a

Plan C 385 372 South Pelto Whiskey Area 3a

Plan D 802 33 South Pelto Whiskey Area 3a

Plan E 1027 33 South Pelto Whiskey Area 3a

Wine

Plan A 5 6 South Pelto Whiskey Area 3a

Plan B 109 97 South Pelto Whiskey Area 3a

Plan C 122 117 South Pelto Whiskey Area 3a

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Island Plan

Dune/

Supratidal

Area at TY1

(acre)

Intertidal

Habitat

at TY1

(acre)

Beach/Dune

Borrow

Area

Marsh

Borrow

Area

Plan D 130 140 South Pelto Whiskey Area 3a

Plan E 349 17 South Pelto Whiskey Area 3a

Ring Only 26 3 South Pelto NA

Timbalier

Plan A 606 374 South Pelto Whiskey Area 3a

Plan B 903 726 South Pelto Whiskey Area 3a

Plan C 1743 85 South Pelto Whiskey Area 3a

Plan D 1952 83 South Pelto Whiskey Area 3a

Plan E 2561 69 South Pelto Whiskey Area 3a

East

Timbalier

Plan A 75 133 South Pelto Whiskey Area 3a

Plan B 376 452 South Pelto Whiskey Area 3a

Plan C 1057 71 South Pelto Whiskey Area 3a

Plan D 1170 60 South Pelto Whiskey Area 3a

Plan E 1762 99 South Pelto Whiskey Area 3a

3.3.3 Screening/Evaluation of Alternative Plans

Because of the millions of potential alternatives comprised of island measure(s) and

borrow area combinations, the PDT utilized the USACE Institute for Water

Resources Planning Suite (IWR). IWR Planning Suite assists with plan

formulation by combining solutions to planning problems and calculating the

additive effects of each combination. It also assists with plan comparison by

conducting cost effectiveness and incremental cost analyses, identifying the plans

which are best financial investments  Best Buy plan alternatives, and displaying

the effects of each on a range of decision variables. IWR Planning Suite 1.0.11.0

was used in IWR screening of the LCA TBBSR Study solutions.

The input variables for the IWR included habitat benefits and costs for each of the

44 island plans identified in Table 3-7. Methodologies for determining habitat

benefits and costs are provided in Sections 3.3.3.1 and 3.3.3.2, respectively.

The user has the option of defining inter-variable dependencies and combinability.

The combinability variable was defined such that none of the plans for a

particular island could be paired with another plan developed for the same island.

For example, Whiskey Island Plan B could not be combined with Whiskey Island

Plan E. Since there were no inter-island dependencies, the dependency variable

was not used in the IWR.

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Once the costs, benefits, and combinability of each island plan were entered into the

input file, the IWR was used to combine the island plans to form a series of

alternatives. An alternative can be comprised of as many as seven and as few as one

island plan. For alternatives with multiple island plans, the costs and benefits of

each plan were summed to determine the total cost and benefit output of the

alternative. The IWR also computes the cost/benefit of each alternative in order to

conduct a cost-effectiveness and incremental cost analysis.

3.3.3.1 Habitat Benefits

The input parameters for the IWR screening run included habitat acres and

conceptual cost estimates specific to the alternatives carried forward through the

plan formulation process. Due to the large number of possible alternatives, the

PDT could not feasibly conduct a Wetland Value Assessment (WVA) to determine

habitat benefits (i.e. average annual habitat units [AAHUs]). Therefore, the PDT

utilized average annual habitat acres (AAHAs) as a surrogate for AAHUs in this

preliminary level of screening. However, the WVA is utilized in subsequent levels

of screening (Section 3.5.1).

In order to calculate AAHAs, the PDT determined the number of acres of dune,

supratidal, and intertidal habitat across the following target years (TY): TY0, TY1,

TY5, TY10, TY20, TY30, TY40, and TY50. Habitat types were defined in

accordance with the WVA:

 Dune Habitat: Habitat > 5 ft NAVD 88

 Supratidal Habitat: Habitat occurring from 2.0 ft to 4.9 ft NAVD 88

 Intertidal Habitat: Habitat occurring from 0.0 ft to 1.9 ft NAVD 88

Initial construction templates (TY1) were evolved in time to account for vertical

adjustments (subsidence and sea level rise) and horizontal adjustments

(background erosion and overwash). Boundaries of habitats at specific target years

delineated both existing and created habitats. Template evolution and calculation of

the target year acres were performed in AutoCAD.

A weighting factor of 17/14ths was then applied to the intertidal habitat acres since

they provide a greater habitat benefit than the other two habitat types. The

relative weight (i.e. the 17/14ths) of the intertidal habitat was reviewed by the

USACE and other agency and academic experts during model development. In

addition, a literature review was conducted to summarize the available scientific

knowledge supporting the relative weights of the variables and their role in

supporting fish and wildlife within the respective communities. The variable

weights were originally developed using a sensitivity analysis in which weights

were adjusted until the model behaved as expected by an interdisciplinary expert

team and a consensus was reached. Unfortunately, the scientific literature to

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support specific numerical weightings of individual variables does not exist;

however, there is general support for their relative values used in the WVA.

The dune, supratidal, and adjusted intertidal acres were summed and then

averaged over the 50-yr period of analysis. This method is consistent with the WVA

method for computing AAHUs except that it does not account for subtidal acreages,

vegetative cover, interspersion, or the influence of structural measures. Tables 3-8

through 3-16 present the habit acres for each target year and the resulting AAHAs.

A detailed description of the WVA model is provided in Section 3.5.1.

Table 3-8. Summary of Habitat Acres for Raccoon Island Restoration Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHA

A

Dune 0000 0 0 0 0

Supratidal 51 51 30 10 3 0 0 0 92

Intertidal 188 184 161 137 76 55 0 0

B

Dune 0 45 33 15 1 0 0 0

Supratidal 51 227 194 162 150 83 25 0 393

Intertidal 188 235 253 266 255 260 248 23

C

Dune 0 50 38 22 8 0 0 0

Supratidal 51 292 215 192 174 110 62 4 489

Intertidal 188 237 300 301 295 306 277 223

D

Dune 0 60 45 25 14 0 0 0

Supratidal 51 460 445 231 210 120 67 29 554

Intertidal 188 122 146 339 335 341 307 263

E

Dune 0 63 50 29 20 0 0 0

Supratidal 51 688 675 657 630 144 72 51 692

Intertidal 188 39 39 40 39 478 457 425

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Table 3-9. Summary of Habitat Acres for Raccoon Island Restoration Plans

with Breakwaters

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHA

A

Dune 0 000 0 0 0 0

Supratidal 51 51 30 10 3 0 0 0 92

Intertidal 188 184 161 137 76 55 0 0

B

Dune 0 45 33 15 6 0 0 0

Supratidal 51 227 198 163 173 112 62 0 418

Intertidal 188 237 254 267 254 264 259 38

C

Dune 0 50 38 22 8 0 0 0

Supratidal 51 292 219 193 200 142 92 14 520

Intertidal 188 239 302 303 297 307 300 262

D

Dune 0 60 45 25 14 0 0 0

Supratidal 51 461 449 232 220 158 96 34 587

Intertidal 188 122 148 340 352 336 339 307

E

Dune 0 63 50 28 20 0 0 0

Supratidal 51 689 679 658 656 188 109 68 727

Intertidal 188 39 40 40 40 467 489 472

Table 3-10. Summary of Habitat Acres for Raccoon Island Restoration

Plans with Terminal Groin

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHA

A

Dune 0 000 0 0 0 0

Supratidal 51 51 30 10 3 0 0 0 92

Intertidal 188 184 161 137 76 55 0 0

B

Dune 0 45 33 15 3 0 0 0

Supratidal 51 227 198 165 170 107 36 0 416

Intertidal 188 237 254 267 254 264 279 34

C

Dune 0 50 38 22 8 0 0 0

Supratidal 51 292 218 194 194 137 86 12 516

Intertidal 188 238 302 302 296 307 300 258

D

Dune 0 60 45 25 14 0 0 0

Supratidal 51 460 448 232 218 156 93 34 581

Intertidal 188 122 147 341 348 332 329 303

E

Dune 0 63 50 29 20 0 0 0

Supratidal 51 688 678 659 650 182 106 66 722

Intertidal 188 38 39 40 39 466 486 468

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Table 3-11. Summary of Habitat Acres for Whiskey Island Restoration

Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHAs

A

Dune 0 0 0 0 0 0 0 0

Supratidal 377 367 40 4 0 0 0 0 348

Intertidal 443 436 692 616 468 0 0 0

B

Dune 0 57 53 0 0 0 0 0

Supratidal 377 614 220 164 0 0 0 0 822

Intertidal 443 509 830 801 786 594 410 276

C

Dune 0 65 61 57 0 0 0 0

Supratidal 377 830 328 223 84 0 0 0 944

Intertidal 443 377 808 828 847 717 472 363

D

Dune 0 69 65 61 0 0 0 0

Supratidal 377 917 533 288 167 1 0 0 1015

Intertidal 443 376 690 850 854 785 521 355

E

Dune 0 80 76 71 0 0 0 0

Supratidal 377 1323 1127 1039 938 259 75 0 1284

Intertidal 443 250 376 379 375 875 782 475

Table 3-12. Summary of Habitat Acres for Trinity Island Restoration Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHAs

A

Dune 39 32 4 3 0 0 0 0

Supratidal 232 206 137 52 3 1 0 0 153

Intertidal 311 326 327 245 72 19 0 0

B

Dune 39 126 92 23 0 0 0 0

Supratidal 232 338 237 208 43 0 0 0 651

Intertidal 311 569 626 629 627 460 279 33

C

Dune 39 129 122 67 0 0 0 0

Supratidal 232 456 316 270 190 4 0 0 777

Intertidal 311 564 632 635 594 561 380 199

D

Dune 39 126 116 102 0 0 0 0

Supratidal 232 1072 1004 351 324 124 0 0 891

Intertidal 311 72 73 642 578 577 501 298

E

Dune 39 123 115 107 0 0 0 0

Supratidal 232 1399 1329 1237 1157 422 217 32 1187

Intertidal 311 67 66 67 69 608 618 593

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Table 3-13. Summary of Habitat Acres for East Island Restoration Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHAs

A

Dune 35 23 5 4 0 0 0 0

Supratidal 178 176 86 46 6 0 0 0 78

Intertidal 71 59 110 101 58 16 0 0

B

Dune 35 88 59 18 0 0 0 0

Supratidal 178 229 165 140 33 0 0 0 422

Intertidal 71 362 404 405 401 290 171 46

C

Dune 35 89 81 50 0 0 0 0

Supratidal 178 296 213 175 122 2 0 0 503

Intertidal 71 372 410 412 388 360 242 122

D

Dune 35 84 74 67 0 0 0 0

Supratidal 178 718 674 231 208 73 0 0 577

Intertidal 71 33 34 418 377 382 314 192

E

Dune 35 77 75 69 0 0 0 0

Supratidal 178 950 898 837 770 273 139 17 780

Intertidal 71 33 33 34 39 402 402 379

Table 3-14. Summary of Habitat Acres for Wine Island Restoration Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHAs

A

Dune 1 0 0 0 0 0 0 0

Supratidal 6 4 3 2 1 0 0 0 4.8

Intertidal 6 7 6 5 3 1 0 0

B

Dune 1 12 11 10 0 0 0 0

Supratidal 5 97 75 61 47 13 0 0 151

Intertidal 6 97 109 109 106 111 96 5

C

Dune 1 13 12 11 0 0 0 0

Supratidal 5 109 90 76 64 29 2 0 185

Intertidal 6 117 125 126 122 129 128 9

D

Dune 1 12 11 10 9 0 0 0

Supratidal 5 118 98 85 62 38 10 0 217

Intertidal 6 140 149 150 146 150 151 7

E

Dune 1 11 10 9 8 0 0 0

Supratidal 5 338 328 314 288 76 47 0 323

Intertidal 6 17 17 17 17 210 210 229

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Table 3-15. Summary of Habitat Acres for Timbalier Island Restoration

Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHAs

A

Dune 57 53 31 8 0 0 0 0

Supratidal 549 529 266 286 93 18 1 0 388

Intertidal 374 373 541 392 289 149 37 2

B

Dune 57 155 130 13 0 0 0 0

Supratidal 549 748 566 524 236 38 1 0 1029

Intertidal 374 726 811 822 829 695 450 175

C

Dune 57 193 160 130 0 0 0 0

Supratidal 549 1550 630 496 438 134 3 0 1254

Intertidal 374 85 916 933 826 833 644 373

D

Dune 57 191 161 136 0 0 0 0

Supratidal 549 1761 1668 600 499 187 4 0 1477

Intertidal 374 83 88 1041 978 994 843 571

E

Dune 57 215 183 160 0 0 0 0

Supratidal 549 2346 2257 2130 1996 629 330 53 2029

Intertidal 374 69 71 74 76 1148 1123 1088

Table 3-16. Summary of Habitat Acres for East Timbalier Island

Restoration Plans

Plan

Habitat

Type

Target Year (TY)

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 AAHAs

A

Dune 7 1 1 0 0 0 0 0

Supratidal 129 74 60 46 9 2 1 0 102

Intertidal 173 133 140 111 98 49 17 4

B

Dune 7 63 58 54 0 0 0 0

Supratidal 129 314 240 199 175 70 7 0 624

Intertidal 173 452 476 474 456 459 405 7

C

Dune 7 86 67 62 0 0 0 0

Supratidal 129 972 327 238 158 52 7 0 892

Intertidal 173 71 702 714 664 587 552 496

D

Dune 7 93 71 66 0 0 0 0

Supratidal 129 1077 1062 351 359 256 157 56 1112

Intertidal 173 60 72 734 673 682 676 670

E

Dune 7 120 83 78 0 0 0 0

Supratidal 129 1641 1617 1587 1556 444 192 244 1709

Intertidal 173 99 91 86 71 1086 1227 1066

Since the IWR requires net benefit acres for each plan, the AAHAs for the No Action

plan (Plan A) were subtracted from the average annual habitat acres for each of the

other plans. The resulting IWR inputs are summarized in Table 3-17.

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3.3.3.2 Costs

The IWR also requires the user to input a cost for each alternative being considered.

The conceptual cost estimates for each island restoration measure utilizing one or

more of the sand and marsh borrow areas were determined by computing the costs

based on equipment types and estimates of production rates, historical contract bids

from projects of a similar nature, and professional experience. Conceptual costs

were developed for individual islands in order to evaluate each measure on a level

and consistent basis. Each island restoration estimate included a dredge plant for

beach/dune fill and a dredge plant for marsh fill. Each dredge equipment cost

estimate included pipeline, equipment mobilization/demobilization, and support

plant. This method allowed for interchangeability of dredge type for beach/dune fill

and marsh fill to evaluate the most efficient method of island restoration. The

resulting costs that were utilized in the IWR are summarized in Table 3-17.

Table 3-17. IWR Input Parameters

Island Description Cost ($1000) Acres

Raccoon

Plan A $0 0

Plan B $54,400 301

Plan C $58,300 397

Plan D $64,100 462

Plan E $81,100 599

Plan B with BW $58,100 326

Plan C with BW $62,000 428

Plan D with BW $67,800 495

Plan E with BW $84,800 635

Plan B with TG $56,600 324

Plan C with TG $60,600 424

Plan D with TG $66,400 489

Plan E with TG $83,400 630

Whiskey

Plan A $0 0

Plan B $63,500 474

Plan C $73,900 596

Plan D $84,500 667

Plan E $124,000 936

Trinity

Plan A $0 0

Plan B $67,100 498

Plan C $77,600 625

Plan D $93,400 738

Plan E $136,700 1035

East

Plan A $0 0

Plan B $56,400 344

Plan C $62,500 426

Plan D $72,600 500

Plan E $102,300 703

Wine

Plan A $0 0

Plan B $42,500 147

Plan C $43,900 181

Plan D $45,800 213

Plan E $51,500 318

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Island Description Cost ($1000) Acres

Ringa $16,400 5

Timbalier

Plan A $0 0

Plan B $83,400 641

Plan C $97,400 865

Plan D $113,000 1088

Plan E $168,000 1641

East Timbalier

Plan A $0 0

Plan B $144,000 523

Plan C $180,000 791

Plan D $229,000 1011

Plan E $375,000 1607

BW denotes Breakwaters

TG denotes Terminal Groin

a This plan includes filling the existing rock ring of Wine Island

A total of 243,750 plans were generated using the IWR platform. The output

included 360 cost-effective plan alternatives ranging in cost between $0 (No Action)

to $1.04 billion (Raccoon with breakwaters, Whiskey, Trinity, East, Wine,

Timbalier, and East Timbalier  all Plan E). Fourteen (14) of the cost effective plans

were Best Buy plans. Figure 3-8 presents an IWR graph which depicts all of the

plans including non cost effective, cost effective and Best Buys.

Figure 3-8. Results of Initial IWR Iteration

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Of the 243,750 Generated Plans, 360 were Cost Effective (blue triangles) and 14

were Best Buys (red squares). The Best Buy plans are summarized in Table 3-18.

Table 3-18. Summary of Best Buy Plans

Best Buy Plans AAHA Cost ($) Cost/AAHA

BB1 No Action 0 0 0

BB2 Timbalier (Plan E) 1,641 168,000,000 102,000

BB3 Whiskey (Plan C), Timbalier (Plane E) 2,237 242,000,000 108,000

BB4 Whiskey (Plan C), Trinity (Plan C), Timbalier

(Plan E)

2,862 319,000,000 112,000

BB5 Raccoon w/TG (Plan E), Whiskey (Plan C),

Trinity (Plan C), Timbalier (Plan E)

3,492 403,000,000 115,000

BB6 Raccoon w/TG (Plan E), Whiskey (Plan C),

Trinity (Plan D), Timbalier (Plan E)

3,605 419,000,000 116,000

BB7 Raccoon w/TG (Plan E), Whiskey (Plan C),

Trinity (Plan D), East (Plan D), Timbalier (Plan

E)

4,105 491,000,000 120,000

BB8 Raccoon w/TG (Plan E), Whiskey (Plan C),

Trinity (Plan E), East (Plan D), Timbalier (Plan

E)

4,402 534,000,000 121,000

BB9 Raccoon w/TG (Plan E), Whiskey (Plan C),

Trinity (Plan E), East (Plan E), Timbalier (Plan

E)

4,605 564,000,000 122,000

BB10 Raccoon w/TG (Plan E), Whiskey (Plan E),

Trinity (Plan E), East (Plan E), Timbalier (Plan

E)

4,945 614,000,000 124,000

BB11 Raccoon w/TG (Plan E), Whiskey (Plan E),

Trinity (Plan E), East (Plan E), Wine (Plan E),

Timbalier (Plan E)

5,264 666,000,000 126,000

BB12 Raccoon w/TG (Plan E), Whiskey (Plan E),

Trinity (Plan E), East (Plan E), Wine (Plan E),

Timbalier (Plan E), East Timb (Plan D)

6,245 895,000,000 143,000

BB13 Raccoon w/TG (Plan E), Whiskey (Plan E),

Trinity (Plan E), East (Plan E), Wine (Plan E),

Timbalier (Plan E), East Timbalier (Plan E)

6,841 1,040,000,000 152,000

BB14 Raccoon w/BW (Plan E), Whiskey (Plan E),

Trinity (Plan E), East (Plan E), Wine (Plan E),

Timbalier (Plan E), East Timbalier (Plan E)

6,846 1,040,000,000 152,000

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3.3.4 Alternative Plans not Carried Over for Further Analysis

Of the 243,750 plans that were generated by the IWR, only ten were carried forward

for further analysis. Five of the plans were selected because they were the five most

cost-effective Best Buy plans. Best buy plans are the most efficient plans because

they provide the greatest increase in output for the least increase in costs. Best Buy

Plan #5 was selected as the cutoff point because the incremental increase in output

between Best Buy Plan #5 and #6 was relatively small compared to the incremental

increase in cost required for the additional output (Figure 3-9). Best Buy Plan #5

also represents a multi-island option with systemic benefits although the

alternative significantly exceeds the currently authorized project cost. All other

Best Buy and Cost Effective Plans were eliminated.

The remaining five plans that were carried forward are unique in that they were

not found to be cost-effective by the IWR. However, they provided additional

benefits that were worthy of consideration and were thus carried forward for

further analysis. The rationale for advancing these multi-island alternatives is

based on a system wide approach of restoring as many of the islands within the

Terrebonne Basin barrier system as possible. The comments received during public

meetings, both project scoping and Coastal Protection and Restoration Authority

stakeholder, expressed a general desire to restore all of the islands in the

Terrebonne Basin. Concentrating restoration efforts on only one or two cost effective

islands may well meet with public opposition. Furthermore, these alternatives may

become cost-effective once AAHUs are substituted for AAHAs. These plans are

discussed in more detail in Section 3.4.

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Figure 3-9. Incremental Cost and Output for the Best Buy Plans

3.4 INTERMEDIATE ARRAY OF ALTERNATIVES

Based on the results of the IWR analysis presented in Section 3.3, five Best Buy

plans were recommended for inclusion in the Intermediate Array of Alternatives

presented. Because the conceptual cost estimates in the IWR screening were

developed separately for individual islands and dune/beach and marsh fill

components, they did not account for potential reductions due to shared

mobilization/demobilization as well as other fixed costs. The conceptual cost

estimates were subsequently refined for analyzing and developing alternatives to

carry forward into the Intermediate Array. For Best Buy plans 4 and 5, the volume

of required marsh fill exceeds the volume of marsh sediments identified in the

available marsh borrow areas, thus, sand borrow areas were selected to provide the

additional sediment to complete the marsh fill templates. However, the sand will

only be used as a base layer. An adequate layer of marsh material will be placed on

the sand layer whenever it is used for marsh construction.

The WVA was applied to compute AAHUs. The Habitat Units, which represent a

numerical combination of quality and quantity existing at any given point in time

resulting from the Future Without and Future With scenarios, were annualized and

BB1

BB2

BB3

BB5 BB6

BB7

BB8

BB10

BB11

BB9

BB13, 14

BB6

BB12

0.0 B

0.2 B

0.4 B

0.6 B

0.8 B

1.0 B

(AAHAs)

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averaged over the Study life to determine AAHUs. The difference in AAHUs

between two scenarios represents the net benefits attributable to the Study in

terms of habitat quality and quantity.

To apply a system-wide approach of restoring as many islands as possible within

the Terrebonne Basin barrier system and to ensure that other alternatives that

could provide effective solutions and are constructible with available sediment

sources, additional solutions were further analyzed. All possible minimized (Plan B)

three- and four-island combinations that could be constructed with available

sediment sources were developed. The most cost effective combinations whose

refined conceptual cost estimate did not exceed the Best Buy plans included in the

Intermediate Array of Alternatives, of which there were four (4), were included in

the Intermediate Array of Alternatives. Finally, a system-wide barrier island

restoration measure which would restore all seven islands to their minimized

design (Plan B) completed the Intermediate Array. The need to consider a systemwide approach was requested by local stakeholders through the scoping process.

In summary, the ten Intermediate Array alternatives were grouped into four (4)

categories.

1) No Action  The No-Action Alternative assumes there would be no future barrier

island restoration within the Study area. The barrier islands will continue to be

subjected to the factors and processes that are contributing to the loss of the

Timbalier and Isles Dernieres barrier island reaches and will result in a direct loss

of the barrier islands to open water.

2) Best Buy  The best-buy alternatives are based on the IWR screening and

provide the greatest increase in the value of the output variable for the least

increase in the value of the cost variable. In other words, the best-buy alternative

yields the maximum habitat acres at the lowest cost per unit. The Best Buy

alternative is geared less toward the system-wide approach of restoring the entire

barrier island reach and more toward restoring the island or islands that are most

cost-effective.

3) Maximum number of islands constructible with available sediment sources - This

alternative would favor those islands where the total costs are lowest, allowing for

more islands to be created using available sediment sources noting they may or may

not be cost effective based on the IWR screening. The rationale for advancing these

alternatives is based on a system wide approach of restoring as many of the islands

within the Terrebonne Basin barrier system as possible. The comments received

during public meetings, both project scoping and Coastal Protection and Restoration

Authority stakeholder, expressed a general desire to restore all of the islands in the

Terrebonne Basin. Concentrating restoration efforts on only one or two cost

effective islands may well meet with public opposition.

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The goal of the LCA Plan is "to reverse the current trend of degradation of the

coastal ecosystem. The plan maximizes the use of restoration strategies that

reintroduce historic flows of river water, nutrients, and sediment to coastal

wetlands, and that maintain the structural integrity of the coastal ecosystem" (LCA

2004). The Timbalier and Isles Dernieres barrier island reaches, made up of seven

individual islands, define the southern extent of the Terrebonne Basin and thus

provide structural integrity to all components to estuarine system further to the

north. The identification of a single island solely because it is the most costeffective alternative based on the tools and metrics prescribed for this Study

discounts the benefits provided by multiple island combinations that go beyond the

AAHUs. The inclusion of this category is consistent with the overall objective of

the LCA Program approach and was included to provide alternatives that otherwise

would have been eliminated due to the methodologies prescribed by the planning

process.

4) System-wide barrier island restoration  This alternative would take a full

system-wide approach to restoring the Terrebonne Basin barrier system. Each of

the seven barrier islands would be restored to their minimal geomorphologic form

and ecologic function. Similar to the alternatives that include the most islands

constructible with available sediment sources, this alternative may or may not be

cost effective based on the IWR screening. The rationale is the same, that being; the

significant stakeholder input received during plan formulation indicates a general

desire to restore all of the islands in the Terrebonne Basin. As with Category 3, the

inclusion of this category is also consistent with the overall objectives of the LCA

Program approach and was included to provide alternatives that otherwise would

have been eliminated due to the methodologies prescribed by the planning process.

It is noted that for this alternative, the volume of required marsh fill exceeds the

volume of marsh sediments identified in the available marsh borrow areas, thus,

sand borrow areas were selected to provide the additional sediment to complete the

marsh fill templates.

Based upon the results of the plan formulation analyses and screening, ten (10)

alternatives have been recommended for inclusion in the Intermediate Array of

Alternatives. The alternatives consist of various combinations of islands, restoration

templates (Plans B through E), and complimentary measures (terminal groins).

The alternatives are discussed in the following sections and summarized in Table 3-

29.

3.4.1 Alternative 1

The No-Action Alternative assumes there would be no future barrier island

restoration within the Study Area. The barrier islands will continue to be subjected

to the factors and processes that are contributing to the loss of the Timbalier and

Isles Dernieres barrier island reaches and will result in a direct loss of the barrier

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islands to open water. Table 3-19 provides a summary of the habitat acres for

Alternative 1 for each target year that was analyzed. The table also presents the

year of disappearance for each habitat type and the AAHUs for each island.

Table 3-19. Summary of Habitat Value for Alternative 1

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

Dune 0 0 0 0 0 0 0 0 NA

44 Supratidal 51 51 30 10 3 0 0 0 TY30

Intertidal 188 184 161 137 76 55 0 0 TY40

Total 239 235 191 147 79 55 0 0 TY40

Whiskey

Dune 0 0 0 00000 NA

179 Supratidal 377 367 40 4 0 0 0 0 TY17

Intertidal 443 436 692 616 468 375 0 0 TY31

Total 820 803 732 620 468 375 0 0 TY31

Trinity

Dune 39 32 4 30000 TY20

116 Supratidal 232 206 137 52 3 1 0 0 TY33

Intertidal 311 326 327 245 72 19 0 0 TY40

Total 582 564 468 300 75 20 0 0 TY40

East

Dune 35 23 5 4 0 0 0 0 TY20

55 Supratidal 178 176 86 46 6 0 0 0 TY29

Intertidal 71 59 110 101 58 16 0 0 TY40

Total 284 258 201 151 64 16 0 0 TY40

Wine

Dune 1 0 0 00000 TY1

5 Supratidal 6 4 3 2 1 0 0 0 TY29

Intertidal 6 7 6 5 3 1 0 0 TY35

Total 13 11 9 7 4 1 0 0 TY35

Timbalier

Dune 57 53 31 8 0 0 0 0 TY20

336 Supratidal 549 529 266 286 93 18 1 0 TY46

Intertidal 374 373 541 392 289 149 37 2 >TY50

Total 980 955 838 686 382 167 38 2 >TY50

East

Timbalier

Dune 7 1 1 0 0 0 0 0 TY10

66 Supratidal 129 74 60 46 9 2 1 0 TY43

Intertidal 173 133 140 111 98 49 17 4 >TY50

Total 309 208 201 157 107 51 18 4 >TY50

Total Dune 139 109 41 15 0 0 0 0 TY20 801

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Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Supratidal 1521 1408 621 446 114 21 2 0 TY46

Intertidal 1566 1517 1978 1608 1065 664 54 6 >TY50

Total 3226 3034 2640 2069 1179 685 56 6 >TY50

aYOD: Year of Disappearance

Although the islands will have some habitat benefit at TY0 (i.e. 2012), they are not

expected to possess adequate landmass or vegetation coverage to provide

geomorphologic form or ecologic function as defined in Section 3.3.2.2.1.

Furthermore, the aerial extent of the islands is expected to rapidly deplete after

TY20. By TY20, the dune habitat on all seven islands is expected to disappear,

followed by supratidal habitat by TY40. At TY50 (the end of our period of analysis),

the only islands that are expected to have intertidal habitat are Timbalier Island (2

acres) and East Timbalier Island (4 acres). By this point, the island system will not

be able to provide any considerable protection from wave action, saltwater

intrusion, storm surge, or tidal currents. Additionally, the islands will no longer be

able to support terrestrial or avian wildlife.

3.4.2 Alternative 2

Alternative 2 includes the restoration of Timbalier Island to its minimal

geomorphologic form and ecologic function along with twenty-five years of advanced

fill. Table 3-20 provides a summary of the habitat acres for Alternative 2 for each

target year that was analyzed. The table also presents the year of disappearance

for each habitat type and AAHUs for each island plan.

Table 3-20. Summary of Habitat Value for Alternative 2

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Timbalier

Plan E

Dune 57 215 183 160 0 0 0 0 TY20

1207 Supratidal 549 2346 2257 2130 1996 629 330 53 >TY50

Intertidal 374 69 71 74 76 1148 1123 1088 >TY50

Total 980 2630 2511 2364 2072 1777 1453 1141 >TY50

a YOD: Year of Disappearance

3.4.3 Alternative 3

Alternative 3 includes the restoration of Whiskey Island to its minimal

geomorphologic form and ecologic function along with five years of advanced fill

combined with restoration of Timbalier Island to its minimal geomorphologic form

and ecologic function along with twenty-five years of advanced fill. Table 3-21

provides a summary of the habitat acres for Alternative 3 for each target year that

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was analyzed. The table also presents the year of disappearance for each habitat

type and AAHUs for each island plan.

Table 3-21. Summary of Habitat Value for Alternative 3

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Whiskey

Plan C

Dune 0 65 61 57 0 0 0 0 TY20

558 Supratidal 377 830 328 223 84 0 0 0 TY30

Intertidal 443 377 808 828 847 717 472 363 >TY50

Total 820 1272 1197 1108 931 717 472 363 >TY50

Timbalier

Plan E

Dune 57 215 183 160 0 0 0 0 TY20

1207 Supratidal 549 2346 2257 2130 1996 629 330 53 >TY50

Intertidal 374 69 71 74 76 1148 1123 1088 >TY50

Total 980 2630 2511 2364 2072 1777 1453 1141 >TY50

Total

Dune 57 280 244 217 0 0 0 0 TY20

1765 Supratidal 926 3176 2585 2353 2080 629 330 53 >TY50

Intertidal 817 446 879 902 923 1865 1595 1451 >TY50

Total 1800 3902 3708 3472 3003 2494 1925 1504 >TY50

a YOD: Year of Disappearance

3.4.4 Alternative 4

Alternative 4 includes the restoration of Whiskey and Trinity Islands to their

minimal geomorphologic form and ecologic function along with five years of

advanced fill combined with restoration of Timbalier Island to its minimal

geomorphologic form and ecologic function along with twenty-five years of advanced

fill. Table 3-22 provides a summary of the habitat acres for Alternative 4 for each

target year that was analyzed. The table also presents the year of disappearance

for each habitat type and AAHUs for each island plan.

Table 3-22. Summary of Habitat Value for Alternative 4

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Whiskey

Plan C

Dune 0 65 61 57 0 0 0 0 TY20

558 Supratidal 377 830 328 223 84 0 0 0 TY30

Intertidal 443 377 808 828 847 717 472 363 >TY50

Total 820 1272 1197 1108 931 717 472 363 >TY50

Trinity Dune 39 129 122 67 0 0 0 0 TY20 504

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Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Plan C Supratidal 232 456 316 270 190 4 0 0 TY31

Intertidal 311 564 632 635 594 561 380 199 >TY50

Total 582 1149 1070 972 784 565 380 199 >TY50

Timbalier

Plan E

Dune 57 215 183 160 0 0 0 0 TY20

1207 Supratidal 549 2346 2257 2130 1996 629 330 53 >TY50

Intertidal 374 69 71 74 76 1148 1123 1088 >TY50

Total 980 2630 2511 2364 2072 1777 1453 1141 >TY50

Total

Dune 96 409 366 284 0 0 0 0 TY20

2269 Supratidal 1158 3632 2901 2623 2270 633 330 53 >TY50

Intertidal 1128 1010 1511 1537 1517 2426 1975 1650 >TY50

Total 2382 5051 4778 4444 3787 3059 2305 1703 >TY50

a YOD: Year of Disappearance

3.4.5 Alternative 5

Alternative 5 includes the restoration of Raccoon Island to its minimal

geomorphologic form and ecologic function along with twenty-five years of advanced

fill with construction of a terminal groin combined with restoration of Whiskey and

Trinity Islands to their minimal geomorphologic form and ecologic function along

with five years of advanced fill and restoration of Timbalier Island to its minimal

geomorphologic form and ecologic function along with twenty-five years of advanced

fill. Table 3-23 provides a summary of the habitat acres for Alternative 5 for each

target year that was analyzed. The table also presents the year of disappearance

for each habitat type and AAHUs for each island plan.

Table 3-23. Summary of Habitat Value for Alternative 5

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

w/TG

Plan E

Dune 0 63 50 29 20 0 0 0 TY21

470 Supratidal 51 688 678 659 650 182 106 66 >TY50

Intertidal 188 38 39 40 39 466 486 468 >TY50

Total 239 789 767 728 709 648 592 534 >TY50

Whiskey

Plan C

Dune 0 65 61 57 0 0 0 0 TY20

558 Supratidal 377 830 328 223 84 0 0 0 TY30

Intertidal 443 377 808 828 847 717 472 363 >TY50

Total 820 1272 1197 1108 931 717 472 363 >TY50

Trinity Dune 39 129 122 67 0 0 0 0 TY20 504

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Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Plan C Supratidal 232 456 316 270 190 4 0 0 TY31

Intertidal 311 564 632 635 594 561 380 199 >TY50

Total 582 1149 1070 972 784 565 380 199 >TY50

Timbalier

Plan E

Dune 57 215 183 160 0 0 0 0 TY20

1207 Supratidal 549 2346 2257 2130 1996 629 330 53 >TY50

Intertidal 374 69 71 74 76 1148 1123 1088 >TY50

Total 980 2630 2511 2364 2072 1777 1453 1141 >TY50

Total

Dune 96 472 416 313 20 0 0 0 TY20

2739 Supratidal 1209 4320 3579 3282 2920 815 436 118.6 >TY50

Intertidal 1316 1048 1550 1577 1556 2434 2385 2078 >TY50

Total 2621 5840 5545 5172 4496 3249 2820 2197 >TY50

a YOD: Year of Disappearance

3.4.6 Alternative 6

Alternative 6 includes the restoration of Raccoon, Whiskey, and Trinity Islands to

their minimal geomorphologic form and ecologic function. Table 3-24 provides a

summary of the habitat acres for Alternative 6 for each target year that was

analyzed. The table also presents the year of disappearance for each habitat type

and AAHUs for each island plan.

Table 3-24. Summary of Habitat Value for Alternative 6

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

Plan B

Dune 0 45 33 15 1 0 0 0 TY21

283 Supratidal 51 227 194 162 150 83 25 0 TY48

Intertidal 188 235 253 266 255 260 248 23 >TY50

Total 239 507 480 443 406 343 273 23 >TY50

Whiskey

Plan B

Dune 0 57 53 0 0 0 0 0 TY10

447 Supratidal 377 614 220 164 0 0 0 0 TY20

Intertidal 443 509 830 801 786 594 410 276 >TY50

Total 820 1180 1103 965 786 594 410 276 >TY50

Trinity

Plan B

Dune 39 126 92 23 0 0 0 0 TY20

394 Supratidal 232 338 237 208 43 0 0 0 TY24

Intertidal 311 569 626 629 627 460 279 33 >TY50

Total 582 1033 955 860 670 460 279 33 >TY50

Total Dune 39 228 178 38 1 0 0 0 TY21 1125

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Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Supratidal 660 1179 651 534 193 83 25 0 TY48

Intertidal 942 1313 1708 1696 1638 1314 937 332 >TY50

Total 1641 2720 2537 2268 1832 1397 962 332 >TY50

a YOD: Year of Disappearance

3.4.7 Alternative 7

Alternative 7 includes the restoration of Raccoon, Whiskey, and Trinity Islands to

their minimal geomorphologic form and ecologic function including the construction

of breakwaters on Raccoon Island. Table 3-25 provides a summary of the habitat

acres for Alternative 7 for each target year that was analyzed. The table also

presents the year of disappearance for each habitat type and AAHUs for each island

plan.

Table 3-25. Summary of Habitat Value for Alternative 7

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

w/BW Plan

B

Dune 0 45 33 15 6 0 0 0 TY21

307 Supratidal 51 227 198 163 173 112 62 0 TY48

Intertidal 188 237 254 267 254 264 259 38 >TY50

Total 239 509 485 445 433 376 321 38 >TY50

Whiskey

Plan B

Dune 0 57 53 0 0 0 0 0 TY10

447 Supratidal 377 614 220 164 0 0 0 0 TY20

Intertidal 443 509 830 801 786 594 410 276 >TY50

Total 820 1180 1103 965 786 594 410 276 >TY50

Trinity

Plan B

Dune 39 126 92 23 0 0 0 0 TY20

394 Supratidal 232 338 237 208 43 0 0 0 TY24

Intertidal 311 569 626 629 627 460 279 33 >TY50

Total 582 1033 955 860 670 460 279 33 >TY50

Total

Dune 39 228 178 38 6 0 0 0 TY21

1147 Supratidal 660 1179 655 535 216 112 62 0 TY48

Intertidal 942 1315 1710 1697 1667 1318 948 347 >TY50

Total 1641 2722 2543 2270 1889 1430 1010 347 >TY50

a YOD: Year of Disappearance

3.4.8 Alternative 8

Alternative 8 includes the restoration of Raccoon, Whiskey, and Trinity Islands to

their minimal geomorphologic form and ecologic function including the construction

of a terminal groin on Raccoon Island. Table 3-26 provides a summary of the habitat

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acres for Alternative 8 for each target year that was analyzed. The table also

presents the year of disappearance for each habitat type and AAHUs for each island

plan.

Table 3-26. Summary of Habitat Value for Alternative 8

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

w/TG Plan

B

Dune 0 45 33 15 3 0 0 0 TY21

299 Supratidal 51 227 198 165 170 107 36 0 TY48

Intertidal 188 237 254 267 254 264 279 34 >TY50

Total 239 509 485 447 427 371 315 34 >TY50

Whiskey

Plan B

Dune 0 57 53 0 0 0 0 0 TY10

447 Supratidal 377 614 220 164 0 0 0 0 TY20

Intertidal 443 509 830 801 786 594 410 276 >TY50

Total 820 1180 1103 965 786 594 410 276 >TY50

Trinity

Plan B

Dune 39 126 92 23 0 0 0 0 TY20

394 Supratidal 232 338 237 208 43 0 0 0 TY24

Intertidal 311 569 626 629 627 460 279 33 >TY50

Total 582 1033 955 860 670 460 279 33 >TY50

Total

Dune 39 228 178 38 3 0 0 0 TY21

1140 Supratidal 660 1179 655 537 213 107 36 0 TY48

Intertidal 942 1315 1710 1697 1667 1318 968 343 >TY50

Total 1641 2722 2543 2272 1883 1425 1004 343 >TY50

a YOD: Year of Disappearance

3.4.9 Alternative 9

Alternative 9 includes the restoration of Raccoon, Whiskey, and Timbalier Islands

to their minimal geomorphologic form and ecologic function. Table 3-27 provides a

summary of the habitat acres for Alternative 9 for each target year that was

analyzed. The table also presents the year of disappearance for each habitat type

and AAHUs for each island plan.

Table 3-27. Summary of Habitat Value for Alternative 9

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

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Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

Plan B

Dune 0 45 33 15 1 0 0 0 TY21

284 Supratidal 51 227 194 162 150 83 25 0 TY48

Intertidal 188 235 253 266 255 260 248 23 >TY50

Total 239 507 480 443 406 343 273 23 >TY50

Whiskey

Plan B

Dune 0 57 53 0 0 0 0 0 TY10

447 Supratidal 377 614 220 164 0 0 0 0 TY20

Intertidal 443 509 830 801 786 594 410 276 >TY50

Total 820 1180 1103 965 786 594 410 276 >TY50

Timbalier

Plan B

Dune 57 155 130 13 0 0 0 0 TY20

718 Supratidal 549 748 566 524 236 38 1 0 TY41

Intertidal 374 726 811 822 829 695 450 175 >TY50

Total 980 1629 1507 1359 1065 733 451 175 >TY50

Total

Dune 57 257 216 28 1 0 0 0 TY21

1448 Supratidal 977 1589 980 850 386 121 26 0 TY48

Intertidal 1005 1470 1894 1889 1870 1549 1108 474 >TY50

Total 2039 3316 3090 2767 2257 1670 1134 474 >TY50

a YOD: Year of Disappearance

3.4.10 Alternative 10

Alternative 10 includes the restoration of Raccoon, Whiskey, Trinity, East, Wine,

Timbalier, and East Timbalier Islands, all to their minimal geomorphologic form

and ecologic function. Table 3-28 provides a summary of the habitat acres for

Alternative 10 for each target year that was analyzed. The table also presents the

year of disappearance for each habitat type and AAHUs for each island plan.

Table 3-28. Summary of Habitat Value for Alternative 10

Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Raccoon

Plan B

Dune 0 45 33 15 1 0 0 0 TY21

284 Supratidal 51 227 194 162 150 83 25 0 TY48

Intertidal 188 235 253 266 255 260 248 23 >TY50

Total 239 507 480 443 406 343 273 23 >TY50

Whiskey

Plan B

Dune 0 57 53 0 0 0 0 0 TY10

447 Supratidal 377 614 220 164 0 0 0 0 TY20

Intertidal 443 509 830 801 786 594 410 276 >TY50

Total 820 1180 1103 965 786 594 410 276 >TY50

Trinity Dune 39 126 92 23 0 0 0 0 TY20 394

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Island Habitat

Type

Habitat Acres

YODa

(TY) AAHUs

TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Plan B Supratidal 232 338 237 208 43 0 0 0 TY24

Intertidal 311 569 626 629 627 460 279 33 >TY50

Total 582 1033 955 860 670 460 279 33 >TY50

East

Plan B

Dune 35 88 59 18 0 0 0 0 TY20

255 Supratidal 178 229 165 140 33 0 0 0 TY22

Intertidal 71 362 404 405 401 290 171 46 >TY50

Total 284 679 628 563 434 290 171 46 >TY50

Wine

Plan B

Dune 1 12 11 10 0 0 0 0 TY19

110 Supratidal 5 97 75 61 47 13 0 0 TY31

Intertidal 6 97 109 109 106 111 96 5 >TY50

Total 12 206 195 180 153 124 96 5 >TY50

Timbalier

Plan B

Dune 57 155 130 13 0 0 0 0 TY20

718 Supratidal 549 748 566 524 236 38 1 0 TY41

Intertidal 374 726 811 822 829 695 450 175 >TY50

Total 980 1629 1507 1359 1065 733 451 175 >TY50

East

Timbalier

Plan B

Dune 7 63 58 54 0 0 0 0 TY20

435 Supratidal 129 314 240 199 175 70 7 0 TY45

Intertidal 173 452 476 474 456 459 405 7 >TY50

Total 309 829 774 727 631 529 412 7 >TY50

Total

Dune 139 546 436 133 1 0 0 0 TY21

2643 Supratidal 1521 2567 1697 1458 684 204 33 0 TY48

Intertidal 1566 2950 3509 3506 3460 2869 2059 565 >TY50

Total 3226 6063 5642 5097 4145 3073 2092 565 >TY50

a YOD: Year of Disappearance

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Table 3-29. Summary of Intermediate Array of Alternatives

Alternative Category

Net

AAHUsa

Preliminary

Costsb

($)

Annualized

Costsc

($)

Annualized

Cost/AAHU Description

1 No Action (Plan A) Best Buy 0d 0 - - This alternative does not include any restoration.2 Timbalier (Plan E) Best Buy 871 170,000,000 8,710,000 10,000

Restoration of Timbalier Island to its minimalgeomorphologic form and ecologic function along withtwenty-five years of advanced fill.

3 Whiskey (Plan C) / Timbalier (Plan E) Best Buy 1250 247,000,000 12,640,000 10,120

Restoration of Whiskey Island to its minimalgeomorphologic form and ecologic function along with fiveyears of advanced fill combined with restoration ofTimbalier Island to its minimal geomorphologic form andecologic function along with twenty-five years ofadvanced fill.

4

Whiskey (Plan C) /Trinity (Plan C) /Timbalier (Plan E)

Best Buy 1637 329,000,000 16,820,000 10,280

Restoration of Whiskey and Trinity Islands to theirminimal geomorphologic form and ecologic function alongwith five years of advanced fill combined with restorationof Timbalier Island to its minimal geomorphologic formand ecologic function along with twenty-five years ofadvanced fill.

5

Raccoon with TG(Plan E) /Whiskey (Plan C) /Trinity (Plan C) /Timbalier (Plan E)

Best Buy 2063 408,000,000 20,830,000 10,100

Restoration of Whiskey and Trinity Islands to theirminimal geomorphologic form and ecologic function alongwith five years of advanced fill combined with restorationof Raccoon and Timbalier Islands to their minimalgeomorphologic form and ecologic function along withtwenty-five years of advanced fill and construction of aterminal groin on the western end of Raccoon Island.

6

Raccoon (Plan B) /Whiskey (Plan B) /Trinity (Plan B)

Max # ofIslandsConstructiblewith AvailableSedimentSources

785 177,000,000 9,040,000 11,510

Restoration of Raccoon, Whiskey, and Trinity Islands, allto their minimal geomorphologic form and ecologicfunction.

7

Raccoon with BW(Plan B) /Whiskey (Plan B) /Trinity (Plan B)

Max # ofIslandsConstructiblewith AvailableSedimentSources

808 182,000,000 9,280,000 11,490

Restoration of Raccoon, Whiskey, and Trinity Islands, allto their minimal geomorphologic form and ecologicfunction, along with construction of eight additionalbreakwaters on the western end of Raccoon Island.

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Alternative Category

Net

AAHUsa

Preliminary

Costsb

($)

Annualized

Costsc

($)

Annualized

Cost/AAHU Description

8

Raccoon with TG(Plan B) / Whiskey(Plan B) / Trinity(Plan B)

Max # ofIslandsConstructiblewith AvailableSedimentSources

801 180,000,000 9,190,000 11,470

Restoration of Raccoon, Whiskey, and Trinity Islands, allto their minimal geomorphologic form and ecologicfunction, along with construction of a terminal groin onthe western end of Raccoon Island.

9

Raccoon (Plan B) /Whiskey (Plan B) /Timbalier (Plan B)

Max # ofIslandsConstructiblewith AvailableSedimentSources

890 199,000,000 10,160,000 11,420

Restoration of Raccoon, Whiskey, and Timbalier Islands,all to their minimal geomorphologic form and ecologicfunction.

10

Raccoon (Plan B) /Trinity (Plan B) /East (Plan B) /Whisky (Plan B) /Timbalier (Plan B) /East Timbalier (PlanB) / Wine (Plan B)

System-wideBarrier IslandRestoration

1842 439,000,000 22,420,000 12,170

Restoration of Raccoon, Whiskey, Trinity, East, Wine,Timbalier, and East Timbalier Islands, all to theirminimal geomorphologic form and ecologic function.

BW: BreakwatersTG: Terminal Groina Net AAHUs are calculated by subtracting the FWOP from the FWP conditions for each of the alternativesb Refined cost represent the total project costs. The costs account for potential reductions due to shared mobilization/demobilization as well

as other fixed costs as described in Appendix L

c Preliminary Costs were annualized at a discount rate of 4.375%, with a base year of 2012. The price level is 2009d Net AAHUs for Alternative 1 (No Action Plan) are zero because there is no project in place to provide additional benefits.

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3.5 COMPARISON OF ALTERNATIVE PLANS

Study alternatives have been evaluated to determine the relative ecosystem

benefits projected for each restoration approach. A cost-effectiveness analysis and

incremental cost analysis were performed by comparing the expected benefits of

various island strategies over a series of target years during the period of analysis.

Benefits for ecosystem function have been determined for the alternatives using the

WVA methodology, described below.

3.5.1 Benefit Analysis

The WVA was chosen as the most appropriate ecological model to assess ecosystem

restoration benefits for the Study based on a number of factors. It is a quantitative,

habitat-based assessment methodology developed to prioritize Louisiana coastal

restoration projects submitted for funding under Coastal Wetlands Planning,

Protection and Restoration Act (CWPPRA). The WVA quantifies changes in fish

and wildlife habitat quality and quantity that are expected to result from a

proposed project. The results of the WVA, measured in Average Annual Habitat

Units (AAHUs), can be combined with cost data to provide a measure of

effectiveness of a proposed project in term of annualized cost per AAHU gain.

Habitat Units (HU) represent a numerical combination of quality and quantity

existing at any given point in time. The HUs resulting from the Future Without

and Future With project scenarios are annualized (averaged over the project life) to

determine AAHUs. The difference in AAHUs between the two scenarios represents

the net benefits attributable to the Study in terms of habitat quality and quantity.

The WVA methodology provides an estimate of the number of acres benefited or

enhanced by the Study and the net acres of habitat protected or restored. WVA was

developed specifically to apply to habitat types present along the Louisiana coast.

The types of variables measured by the WVA community models are sensitive to the

types of changes that are intended outcomes for barrier shoreline and marsh

restoration. The variables measured by WVA are also recognized scientifically and

technically as important in characterizing overall habitat quality. Variables

utilized in the WVA were selected from existing, widely accepted Habitat

Evaluation Procedures (HEP) models. The variables were constituted such that

data were easily estimated or collected from existing data sources.

The specific community model used to evaluate the ecosystem benefits of the Study

alternatives was the Barrier Island Community Model. The model was developed

with detailed consideration of peer reviewed scientific literature, existing data

bases, as well as professional experiences. In addition, unpublished ecological

studies and data sets, as well as professional judgments from many different

Federal and State agency personnel and academics were considered in developing

and supporting the assumptions, variables, and other model components. WVA

models employ a community approach which assumes that optimal conditions for all

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fish and wildlife within a specific type of coastal wetland habitat can be

characterized by a group of significant variables, and that existing or future

conditions can be compared to that optimum, providing an index of habitat quality

similar to those developed under HEP.

HEP is widely used by the US Fish and Wildlife Service and other Federal and

State agencies in evaluating the impacts of development projects on fish and

wildlife resources. However, the HEP generally uses a species-oriented approach,

whereas the WVA utilizes a community approach. The WVA models have been

developed for determining the suitability of coastal wetlands in providing resting,

foraging, breeding, and nursery habitat to a diverse assemblage of fish and wildlife

species.

The WVA model is presently undergoing model certification in accordance with

USACE EC 1105-2-407, May 2005 Planning Models Improvement Program: Model

Certification. The WVA model has undergone external review which is documented

in the July 8, 2009, Draft Model Certification Review Report for the Wetland Value

Assessment Models prepared by the Battelle Memorial Institute for the US Army

Corps of Engineers, Ecosystem Planning Center of Expertise. The WVA revision

documentation and spreadsheets have been submitted to the Ecosystem Center of

Expertise (ECO-PCX). The ECO-PCX has reviewed the revisions and will forward a

recommendation to certify the model for use in the LCA projects.

Since the WVA was still in the process of being certified by the ECO-PCX, the

projects using the WVA model were required to respond to specific comments

related to the ongoing certification process and the use of WVA on the specific

project. The specific comments and responses for the WVA as it relates to the LCA

TBBSR Study can be found in Appendix K. Based on satisfactory responses to these

comments Planning Center of Expertise for Ecosystem Restoration has cleared the

WVA model for use in evaluating the alternatives considered in this report.

The WVA Barrier Island Community Model utilizes seven variables to quantify

habitat value. Information on the evolution and justification of these variables can

be found in the guidance document for the model (CWPPRA, 2002). The variables

are discussed in the following sections:

Variable V1: Dune Habitat - Dune habitat is defined as subaerial habitat > 5 ft

NAVD 88 and encompasses foredune, dune, and reardune. Although dune habitat

occurs at elevations below 5ft NAVD 88, lower-elevation dunes are more ephemeral

and more frequently overwashed, which reduces their habitat value. The variable

is calculated as the percent of the total subaerial area that is classified as dune

habitat.

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Variable V2: Supratidal Habitat  Supratidal habitat occurs from 2.0 ft NAVD 88 to

4.9 ft NAVD 88. This habitat type primarily encompasses swale and may include

low-elevation dune and beach habitat. The variable is calculated as the percent of

the total subaerial area that is classified as supratidal habitat.

Variable V3: Intertidal Habitat  Intertidal habitat occurs from 0.0 ft NAVD 88 to

1.9 ft NAVD 88. This habitat type encompasses intertidal marsh, mudflats, beach,

and any other habitat within that elevation range on the gulfside and bayside of the

barrier island. The variable is calculated as the percent of the total subaerial area

that is classified as supratidal habitat.

Variable V4: Vegetative Cover  The variable is calculated as the percent of

vegetative cover of the dune, supratidal, and intertidal habitats. Dune species

commonly include beach tea, bitter panicum, morning glory, and marshhay

cordgrass. Common supratidal species include goldenrod, marshhay cordgrass,

saltgrass, saltwort, seashore paspalum, and smooth cordgrass. Intertidal species

typically include smooth cordgrass, and black mangroves.

Variable V5: Woody Species  This variable is intended to capture the habitat value

of areas vegetated by woody species. Common woody species include black

mangrove, eastern baccharis, wax myrtle, and marshelder. The variable is

calculated as the percent of the subaerial vegetated area consisting of at least two

woody species.

Variable V6: Edge and Interspersion  This variable is intended to capture the

relative juxtaposition of intertidal, subaerial habitat (vegetated and unvegetated)

and intra-island aquatic habitats such as ponds, lagoons, and tidal creeks

associated with barrier islands. The variable is made up of five classes:

 Class 1 (V6 = 1.0): Represents unvegetated flats and healthy back-barrier

marsh with a high degree of tidal creeks, tidal channels, ponds, and/or

lagoons.

 Class 2 (V6 = 0.8): Represents a high degree of interspersion, but usually

indicates the beginning of marsh breakup and degradation.

 Class 3 (V6 = 0.6): Represents the development of larger open water areas due

to overwash and subsidence. Class 3 is also applied to projects designed to

create intertidal marsh because they lack functionally distinct interspersion

and provide basically one intertidal habitat type.

 Class 4 (V6 = 0.4): Represents extreme stages of subsidence of the dominance

of breaching with unstable overwash flats.

 Class 5 (V6 = 0.1): Consists of no emergent, intertidal land.

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A high degree of dispersion is considered to be optimal (V6 = 1.0) and the lowest

expression of interspersion (open water) is assumed to be less desirable in terms of

community-based function quality (V5 = 0.1).

Variable V7: Beach Zone Habitat  This variable is intended to capture the habitat

value of the beach/surf zone. The variable is made up of five classes:

 Class 1 (V7 = 1.0): Natural beach / unconfined disposal

 Class 2 (V7 = 0.8): Confined disposal

 Class 3 (V7 = 0.9): Breakwaters

 Class 4 (V7 = 0.2): Rock on beach

 Class 5 (V7 = 0.1): Seawall / no emergent habitat

A Project Information Sheet (PIS) was developed by the USFWS to document the

rationale used to quantify the variables and associated suitability indices for each

alternative in the Intermediate Array. The PIS is provided Appendix B.

Table 3-30 presents a summary of the variables calculated for Raccoon Island Plan

B. As seen in this example, percentages of dune and supratidal habitat are highest

at TY1 (i.e. immediately after construction) and are eventually converted to

intertidal habitat through overwash and subsidence.

Variable 4 indicates that vegetative covering is lowest at TY1 since the vegetation is

not planted until TY2 or TY3. By TY5, vegetation has been planted and is

established. However, vegetative coverage decreases after TY5 as the vegetated

dune disappears. At TY1, the percentage of vegetation that is woody species (V5) is

relatively high because of the existing mangrove flats that were avoided during

construction. This percentage drastically decreases by TY5. Although the

mangrove flats are still present, they represent a much smaller percentage of the

total vegetated area once the dunes and marshes are planted with grasses.

Interspersion (V6) is relatively low at TY0, but only slightly increases after

construction. This is because newly constructed marsh is categorized as a Class 3

since it does not have any tidal inlets or canals. However, by TY5, intertidal inlets

have begun to form, thus creating a more optimal interspersion condition. After

TY5, subsidence and overwash continuously increase interspersion to sub-par

levels.

Variable 7 quantifies the effects of hard structures on the surf zone habitat. In this

particular example, a hard structure has not been proposed for Plan B. However,

there are two existing breakwater fields that impact approximately 55% of the

beach. Therefore, 55% of the island was categorized as Class 3 (breakwaters) and

the remaining 45% was categorized as Class 1 (natural beach). It was assumed that

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the breakwaters would no longer be effective at TY30 and that the entire island

would be categorized as Class 1.

Table 3-30. WVA Variables for Raccoon Island Plan B

Target

Year V1 V2 V3 V4 V5 V6 V7

TY0 0% 21% 79% 17% 43% 0.64 0.95

TY1 9% 45% 46% 16% 43% 0.70 0.95

TY5 7% 40% 53% 64% 12% 0.98 0.95

TY10 3% 37% 60% 60% 15% 0.95 0.95

TY20 0% 37% 63% 52% 22% 0.78 0.95

TY30 0% 24% 76% 37% 23% 0.70 1.00

TY40 0% 9% 91% 22% 23% 0.68 1.00

TY50 0% 0% 100% 14% 20% 0.40 1.00

The variables are combined in the following equation to yield a Habitat Suitability

Index (HSI):

HSI = 0.14(V1) + 0.14(V2) + 0.17(V3) + 0.20(V4) + 0.10(V5) + 0.15(V6) + 0.10(V7)

The HSI is then multiplied by the total Study area to determine HUs. Habitat Units

represent a numerical combination of quality (HIS) and quantity (acres) existing at

any given point in time. The HUs resulting from the Future Without and Future

With Project scenarios are annualized (averaged over the project life) to determine

AAHUs. The "benefit" of a project can be quantified by comparing AAHUs between

the Future Without and Future With Project scenarios. The difference in AAHUs

between the two scenarios represents the net benefit attributable to the Study in

terms of habitat quantity and quality.

The variable weights used to calculate the HIS were originally developed using a

sensitivity analysis in which weights were adjusted until the model behaved as

expected by an interdisciplinary expert team and a consensus was reached. Since

their original development, the model has been revised as issues have arisen during

its application. These changes have often modified the procedures used or the

guidance for valuing specific variables. Prior to its use model behavior has been

assed via various means of internal testing using test data sets and variable

sensitivity tests using the full range of variable values.

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3.5.2 Cost Effectiveness and Incremental Cost Analyses

For environmental planning, where traditional benefit-cost analysis is not possible

because costs and benefits are expressed in different units, two analytical methods

are used to assist in the decision process. First, cost effectiveness analysis is

conducted to ensure that the least cost solution is identified for each possible level of

environmental output. Subsequent incremental cost analysis of the cost effective

solutions is conducted to reveal changes in costs for increasing levels of

environmental outputs producing "Best Buy" plans which are simply those plans

that provide increases in output at the lowest average cost. In the absence of a

common measurement unit for comparing the non-monetary benefits with the

monetary costs of environmental plans, cost effectiveness and incremental cost

analysis are valuable tools to assist in decision making. It is important to keep in

mind that the most useful information developed by these two methods is what it

tells decision makers about the relative relationships among solutions - that one

will likely produce greater output than another, or one is likely to be more costly

than another - rather than the specific numbers that are calculated. Furthermore,

these analyses will usually not lead, and are not intended to lead, to a single best

solution (as in economic cost-benefit analysis); however, they will improve the

quality of decision making by ensuring that a rational, supportable approach is used

in considering and selecting alternative methods to produce environmental outputs.

Cost Effectiveness and Incremental Cost Analyses (CE/ICA) are applied to evaluate

alternative plans and identify a NER Plan. The process ensures the NER Plan

meets the planning objectives and constraints and reasonably maximizes

environmental benefits while meeting tests of completeness, acceptability,

efficiency, and effectiveness. The NER Plan is usually based on the array of Best

Buy plans identified during the cost effectiveness and incremental cost analysis.

The CE/ICA analysis follows guidance from the USACE Institute for Water

Resources publication, Evaluation of Environmental Investment Procedures

Manual, Interim: Cost Effectiveness and Incremental Analyses, May 1995, IWR

Report #95-R-1. The costs are converted to average annual costs and include PED

and construction costs, interest during construction, as well as operations and

maintenance costs after construction. The benefits were derived from the WVA and

are also in the form of average annual outputs.

3.5.2.1 Cost Effectiveness

Table 3-31 displays the six cost-effective plans in the Intermediate Array. The cost

effective plans are the alternatives that produce the most benefits for the same or

less cost. A description of the cost effectiveness analysis is included in the

Incremental Costs Analysis Appendix (Appendix K).

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Table 3-31. Cost Effective Alternatives

Code Description

Outputs

(AAHU)

Annualized

Cost

($)

Annualized

Cost/

AAHU

Alt 1 No Action (Plan A) 0 0 0

Alt 2 Timbalier (Plan E) 871 8,710,000 10,000

Alt 9 Raccoon (Plan B) / Whiskey (Plan B) /

Timbalier (Plan B) 890 10,160,000 11,420

Alt 3 Whiskey (Plan C) / Timbalier (Plan E) 1250 12,640,000 10,120

Alt 4 Whiskey (Plan C) / Trinity (Plan C) /

Timbalier (Plan E) 1637 16,820,000 10,280

Alt 5 Raccoon with TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E) 2063 20,830,000 10,100

Figure 3-10 graphically presents the ten alternatives in the Intermediate Array.

Note that the cost-effective and Best Buy alternatives fall along the efficient

frontier.

Figure 3-10. Results of Final IWR Iteration

As seen in Figure 3-10, the CE/ICA analysis revealed that Alternatives 6, 7, 8, and

10 were not cost-effective when compared to the other alternatives in the

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Intermediate Array. Alternatives 6, 7, and 8 provide 785, 808, and 801 Net AAHUs

at a cost of $177,000,000, $182,000,000, and $180,000,000, respectively. However,

Alternative 2 provides more benefits (871 AAHUs) for less cost ($170,000,000).

Therefore, Alternatives 6, 7, and 8 are not cost-effective when compared to

Alternative 2. Similarly, Alternative 10 provides fewer benefits (1842 AAHUs) than

Alternative 5 (2063 AAHUs) at a greater cost and was therefore not cost-effective.

Although there is a general positive sloping trend between costs and outputs (i.e.

benefits), the trend is not completely linear. A combination of factors contribute to

this non-linearity including number of islands in the alternative, characteristics of

the existing island footprints, and the extent to which the islands are being

restored. For example, Alternative 2 consists of restoring Timbalier Island (the

largest island in the system) using the largest island plan (Plan E). Alternatives 6,

7, and 8 will restore three smaller islands (Raccoon, Whiskey, and Trinity) using

smaller island plans (Plan B). These alternatives will require three separate

mobilization/demobilization events (compared to just one for Alternative 2),

considerably increasing the costs per benefit. Furthermore, Timbalier currently has

a considerable amount of subaerial habitat and a shallow sloping subtidal region

behind the island. Therefore, the restoration plan will require relatively less

material to increase its habitat value when compared to Alternatives 6, 7, and 8

which will require fill placement in deeper water.

This phenomenon can also be seen when comparing Alternative 5 to Alternative 10.

Although Alternative 5 is only restoring four islands (compared to seven islands in

Alternate 10), it will produce a larger amount of AAHUs. This is because the

islands in Alternative 5 are being restored using larger plans (Plan E for Raccoon

and Timbalier and Plan C for Whiskey and Trinity) than Alternative 10, which

restores the islands to the minimum plan (Plan B). Furthermore, the additional

mobilization/ demobilization costs associated with a seven-island plan also increase

the cost per benefit.

3.5.2.2 Incremental Cost Analysis

The cost effectiveness and incremental cost analyses process is an iterative process.

For the incremental cost analysis, the cost effective alternative plans were sorted in

order of increasing output (Table 3-32). Next, the plan with the lowest average

annual cost per AAHU beyond the No-Action plan was identified and selected as

the first Best Buy plan. The process continues, searching for the greatest

increases in output for the least increases in cost. The alternatives were analyzed

in all possible combinations. A description of the incremental cost analysis is

located in the Benefit/Cost  Incremental Analysis Appendix (Appendix K).

Table 3-32. Incremental Cost Analysis

Code Outputs Total Additional Additional Incremental Category

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(AAHU) Cost

($)

Output

(AAHU)

Costs

($)

Costs

($/AAHU)

Alt 1 0 0- - 0 Best Buy

Alt 2 871 170,000,000 871 170,000,000 195,000 Best Buy

Alt 9 890 199,000,000 19 29,000,000 1,530,000 Cost

Effective

Alt 3 1,250 247,000,000 360 48,000,000 133,000 Cost

Effective

Alt 4 1,637 329,000,000 387 82,000,000 212,000 Cost

Effective

Alt 5 2,063 408,000,000 426 79,000,000 185,000 Best Buy

A graphical representation of the incremental analysis for the Best Buy plans

(excluding the No Action Plan) is provided in Figure 3-11. As seen in the figure,

Alternative 5 provides considerably more output for a slight increase in incremental

cost.

Figure 3-11. Incremental cost and output for the Best Buy plans

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3.5.2.3 Final Array of Alternatives

The ten alternatives that were selected for the Intermediate Array were further

analyzed and screened to narrow the alternative selection to a final array of five

alternatives and the no action plan. The resulting Final Array consists of the

following alternatives:

Alternative 2: Timbalier (Plan E)

Alternative 3: Whiskey (Plan C)/Timbalier (Plan E)

Alternative 4: Whiskey (Plan C)/Trinity (Plan C)/Timbalier (Plan E)

Alternative 5: Raccoon with TG (Plan E)/Whiskey (Plan C)/Trinity (Plan

C)/Timbalier (Plan E)

Alternative 11: Whiskey (Plan C)

These alternatives were carried forward for detailed analysis because they were all

cost effective and fell along the efficient frontier curve. Alternatives 6, 7, 8, 9, and

10 were not cost effective and therefore, not carried forward for further analysis.

Alternative 9 was also removed from further analysis because the cost per AAHU

was significantly (14%) higher than Alternative 2 and it fell above the efficient

frontier curve. Alternative 11 was added to the final array because none of the

alternatives in the intermediate array were within WRDA 2007 authorization.

Discussion of the development and selection of Alternative 11 is included in Section

3.7.

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3.6 NER PLAN

The USACE objective in ecosystem restoration planning is to contribute to the NER

Plan. Contributions to national ecosystem restoration (NER outputs) are increases

in the net quantity and/or quality of desired ecosystem resources. Measurement of

NER is based on changes in ecological resource quality as a function of

improvement of habitat quality and/or quantity and expressed quantitatively in

physical units or indexes (ER 1105-2-100).

As identified through three levels of screening, the measures carried forward into

the alternatives development stage included, at a minimum, a beach, dune, and

marsh component. During the plan formulation PDT meetings, the NER Plan was

defined as the most cost effective plan that yielded the optimal habitat benefits from

restoring the geomorphologic form and ecologic function of the beach, dune and

marsh components on one or more of the islands.

Alternative 5 (Raccoon with Terminal Groin (Plan E) / Whiskey (Plan C) / Trinity

(Plan C) / and Timbalier (Plan E)) was selected as the NER Plan because it is a Best

Buy plan that fulfills the planning objectives in Section 2.3 of this report. The NER

Plan would restore the geomorphologic form and ecologic function of the four islands

in the Terrebonne Basin barrier system. Immediately after construction (TY1), the

NER Plan would add 3,283 acres of habitat (dune, intertidal, and supratidal) to the

existing island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands,

increasing the total size of the islands to 5,840 acres. This would result in the

restoration and creation of approximately 472 acres of dune, 4,320 acres of

supratidal habitat, and 1,048 acres of intertidal habitat.

The creation of dune, supratidal, and intertidal habitats would provide essential

habitats for fish, migratory birds, and other terrestrial and aquatic species.

Furthermore, by using the proposed borrow areas, the Study would increase

sediment input to supplement longshore sediment transport processes along the

gulf shoreline by mechanically introducing compatible sediment, and increasing the

ability of the restored area to continue to function and provide habitat with

minimum continuing intervention. Sediment placed on Trinity Island would

eventually be transported to Whiskey Island and Raccoon Island as the sediment

moves westward through the system. Raccoon Island would also receive sediment

directly from Whiskey.

The NER Plan was also selected because it would protect existing critical habitat on

Raccoon and Whiskey Islands. Raccoon Plan E and Whiskey Plan C were designed

to avoid approximately 58 and 286 acres of existing mangroves on the islands,

respectively, thereby minimizing potential adverse ecologic impacts during

construction. Since these two islands are considered to be valuable wildlife habitats

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(Isles Dernieres Barrier Islands Wildlife Refuge) and the LDWF is reestablishing a

pelican rookery on Whiskey Island, maintaining adequate areas of healthy beach,

dune, and marsh is particularly important. Raccoon, Whiskey, Trinity, and

Timbalier are also a critical habitat for endangered species including the piping

plover and are a valuable stopover habitat for migratory birds.

In addition to protecting and maintaining ecological benefits, the NER Plan would

protect existing State investments on the island. For example, Whiskey Plan C was

designed to complement TE-50, which is an existing CWPPRA project that was

constructed in 2009. TE-50 created approximately 316 acres of intertidal backbarrier marsh between the two existing mangrove stands. Restoration of the beach

and dune gulfward of TE-50 will supplement the existing CWPPRA investment.

Raccoon Plan E was designed to complement two separate CWPPRA projects, TE-29

and TE-48. The TE-29 project, which was completed in July 1997, included the

construction of eight segmented breakwaters along the eastern end of the island.

The TE-48 project consists of two phases. Phase A, which included the construction

of eight additional segmented breakwaters and a terminal groin, was completed in

September of 2005. The terminal groin, which was constructed on the eastern end

of the island, was intended to prevent longshore currents from scouring

accumulated sediment behind the breakwater field. Phase B, which is currently in

the pre-construction phase, will include the construction of a 53-acre marsh along

the backside of the island. The resilience of Raccoon Island Plan E is partially due

to the existing breakwaters from both CWPPRA projects. The plan would help

protected the marsh that will be constructed as part of TE-48.

The existing mangrove stands and CWPPRA projects on Raccoon and Whiskey

Island can be avoided without undermining the proposed action because they are

the only areas of sufficient elevation to complement the design template and to

contribute to the geomorphologic form and ecologic function of the islands.

Avoidance of other pockets of existing habitat could potentially undermine the

project by providing weak spots in the template. These areas could be more

susceptible to breaching and could accelerate erosion. Therefore, the remaining 124

acres of habitat on Raccoon Island and 201 acres on Whiskey Island would be

covered with fill material during construction of the template (i.e. at TY1). Existing

habitat on Trinity and Timbalier Islands can not be avoided without jeopardizing

the proposed action. Although the entire footprints of both islands (564 acres on

Trinity and 955 acres on Timbalier) would be covered with fill material, these areas

would be restored through the vegetative planting efforts immediately following

construction. The habitat composition of the islands immediately preceding

construction (i.e. TY1) is provided in Table 3-19.

The non-Federal sponsor fully supports Alternative 5 as the NER Plan.

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3.6.1 Renourishment

The initial plan formulation process focused on the identification of the alternative

which provided the best performance in the absence of future enhancements. Based

on initial construction costs and benefits, Alternative 5 was determined to be a Best

Buy and was identified as the NER Plan. However, none of the alternatives

considered met the evaluation criteria of acceptability per ER 1105-2-100. More

specifically, none of the alternatives were found to provide a sustainable

environment and subsequently would not be capable of maintaining the Study

objectives. Consequently, O&M in the form of renourishment was added to each of

the islands found in the Intermediate Array.

The PDT optimized the renourishment quantity and sequencing by determining the

minimum amount needed to maintain the geomorphic form and ecologic function of

the islands throughout the 50-year period of analysis. The first step in this process

involved determining the minimum width of the supratidal beach that would not

breach during each of the three design storms (i.e. the Katrina/Rita event, the

Gustav/Ike event, and the 50-yr design storm). Comparisons of the SBEACH

modeling results revealed that the Katrina/Rita event resulted in the largest

amount of shoreline erosion at 104 ft. Therefore, the supratidal beach must be at

least 104 ft wide in order to prevent breaching and thus maintain the

geomorphologic form and ecologic function.

With the minimum supratidal beach dimensions set at 104 ft, the PDT utilized an

iterative process to determine the most appropriate target years for renourishment.

This was accomplished by restoring the dune and supratidal portions of various

islands plans (i.e. Plan B, Plan C, Plan D, and Plan E) at various target years. The

minimum island plan and maximum renourishment interval that maintained the

geomorphologic form and ecologic function throughout the period of analysis was

selected as the renourishment configuration. This approach minimized the amount

of sediment needed for renourishment, thus reducing costs. The resulting

configurations are provided in Table 3-33. Marsh renourishment was not included

since the initial restoration plan provides for significant intertidal habitat

throughout the 50 year period of analysis.

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Table 3-33. Renourishment sequencing and quantities

Island Plan Renourishment Year Renourishment Plan

Raccoon Plan E w/ TG TY30 Restore Plan B

Whiskey Plan Ca

TY20 Add Plan C

TY40 Add Plan B

Trinity Plan C TY25 Add Plan C

Timbalier Plan E TY30 Restore Plan B

a Whiskey would require two renourishments, one at TY20 and one at TY40

An additional incremental analysis was conducted on each of the 10 alternatives in

the Intermediate Array. The analyses utilized an extrapolation of preliminary cost

and benefit data (i.e. AAHUs) for each alternative to predict the cost-effectiveness of

renourishment. When compared to all other alternatives with renourishment,

Alternative 5 with renourishment is still a Best Buy per the CE/ICA analysis

(Figure 3-12).

Figure 3-12. Incremental cost and output for the Best Buy plans with

Renourishment

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When each island with renourishment is incrementally analyzed individually and in

all possible combinations, other alternative combinations not previously identified

in the Intermediate Array provided cost effective solutions. The identified NER

Plan falls within the uncertainty band of cost-effective plans, but not on the cost

effective frontier. The major difference between the results of the analysis of the

initial ten alternatives versus the analysis of the individual combination of islands

is the effect of discounting the future costs of the renourishment cycles resulting in

alternatives with costs in the outlying years appearing to be more cost effective

than those alternatives with greater initial construction costs. The analysis of all

possible combinations determined that the alternative that is the same as the

previously determined NER Plan with the exception of the inclusion of Timbalier

Plan B instead of Timbalier Plan E is more cost effective. While the benefits created

by both plans are similar, the alternative with Plan B appears to be more cost

effective because its costs are further in the future, while the Plan E is more costly

during the initial construction. However, greater potential for, and certainty of

benefits is attained in the initial construction. As a result, the previously identified

four-island plan remains the NER Plan.

Raccoon Plan E would be renourished at TY30 by adding adequate sediment such

that the dune and supratidal beach acres would be equivalent to that of a newly

constructed Plan B template (i.e. restore a Plan B at TY30). No additional marsh

material would be added. The resulting habitat acres, including renourishment, are

provided in Table 3-34.

Whiskey Plan C would require two renourishment intervals. The first would occur

at TY20 and would include the addition of the same amount of dune and supratidal

beach habitat that was originally created in TY1 (i.e. add a Plan C to the template

at TY20). The second renourishment interval would occur at TY40 and would

include the addition of the same amount of dune and supratidal beach habitat

needed to construct a Plan B template. No additional marsh material would be

added. The resulting habitat acres, including renourishment, are provided in Table

3-34.

Trinity Plan C would be renourished at TY25 by adding the same amount of dune

and supratidal beach habitat that was originally added in TY1 (i.e. add a Plan C to

the template at TY20). No additional marsh material would be added. The

resulting habitat acres, including renourishment, are provided in Table 3-34.

Timbalier Plan E would be renourished at TY30 by adding adequate sediment such

that the dune and supratidal beach habitat acres would be equivalent to the acres of

a newly constructed Plan B template (i.e. restore a Plan B at TY30). No additional

marsh material would be added. The resulting habitat acres, including

renourishment, are provided in Table 3-34.

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Table 3-34. Habitat Acres for Alternative 5 (NER PLAN)  Future With Project (FWP) Conditions

Island

Habitat

Type

Habitat Acres  FWP

TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

Raccoonw/TGPlan E

Dune 0 63 50 29 20 18 10 8 0 45 15 14 3

Supratidal 51 688 678 659 650 603 416 369 182 204 165 166 170

Intertidal 188 38 39 40 39 82 253 295 466 468 486 484 468

Total 239 789 767 728 709 703 679 672 648 717 666 664 641

WhiskeyPlan C

Dune 0 65 61 57 0 65 61 61 57 51 0 57 0

Supratidal 377 830 328 223 84 496 375 344 223 209 84 387 164

Intertidal 443 377 808 828 847 834 782 769 717 693 472 461 363

Total 820 1272 1197 1108 931 1395 1218 1174 997 953 556 905 527

TrinityPlan C

Dune 39 129 122 67 0 0 0 129 122 113 34 30 0

Supratidal 232 456 316 270 190 170 90 496 320 311 230 216 90

Intertidal 311 564 632 635 594 595 597 590 561 543 380 362 199

Total 582 1149 1070 972 784 765 687 1215 1003 967 644 608 289

TimbalierPlan E

Dune 57 215 183 160 0 0 0 0 0 155 13 12 0

Supratidal 549 2346 2257 2130 1996 1859 1313 1176 629 667 524 495 236

Intertidal 374 69 71 74 76 183 612 719 1148 1146 1123 1120 1088

Total 979 2630 2511 2364 2072 2043 1925 1895 1777 1968 1660 1626 1324

Total

Dune 95 472 416 313 20 83 71 198 179 364 62 113 3

Supratidal 1209 4320 3579 3282 2920 3129 2193 2385 1354 1391 1003 1264 660

Intertidal 1315 1048 1550 1577 1556 1694 2244 2373 2892 2849 2461 2427 2118

Total 2619 5840 5545 5172 4496 4905 4508 4956 4425 4604 3526 3803 2781

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The modeling analysis of Whiskey Island (Table 3-3) showed that the additional

benefits provided by the breakwaters could not be justified by the additional costs

associated with their construction. Consequently, they were eliminated in

accordance with the efficiency criteria stipulated by ER1105-2-100 (USACE,

2000). The PDT revisited this analysis to confirm that the incorporation of

renourishment would not impact the cost effectiveness of the breakwaters.

The breakwaters were designed to reduce longshore erosion rates for a period of 20

years. During the 20-year period, the structures would be maintained and repaired,

if necessary. After 20 years, the effectiveness of the structural measures is

projected to substantially diminish because of the sea-level change, subsidence, and

barrier island landward migration. Maintenance of the structures to the original

design after 20 years will no longer result in the same level of function and benefits

as the original structures once provided. For example, as the islands continue to

migrate further landward, they would become spatially disconnected from the

breakwaters. Even if the breakwaters were completely rebuilt to their original

design at TY20, they would be too far from the island to be effective.

After 20 years, the longshore erosion rates are expected to return to preconstruction conditions. Consequently, the islands are expected to lose their

geomorphic form and ecologic function prior to TY50 and will be susceptible to

breaching. Therefore, a renourishment event will be required to sustain the islands

for the entire 50-year period of analysis.

Although the addition of breakwaters will delay the renourishment event to a later

target year, they cannot be used in lieu of renourishment. That is, the alternative

for Whiskey Island with breakwaters will still require renourishment to sustain the

island's geomorphic form and ecologic function for the entire 50-year period of

analysis. Therefore, the additional construction and O&M costs associated with the

breakwaters still can not be justified by the additional benefits they provide. This

also applies to additional breakwaters on Raccoon Island as well as breakwaters on

Trinity and Timbalier Island.

3.6.2 Costs

The preliminary cost estimates that were used when evaluating the Intermediate

Array were refined for the NER Plan using the Micro-Computer Aided Cost

Estimating System (MCACES), Second Generation (MII) to develop a baseline

project cost for initial restoration (Appendix L). The refinements included a more

detailed assessment of costs associated with mobilization/demobilization, refined

dredge-to-fill ratios, beach/dune fill placement, marsh fill placement, containment

dikes, access channel, sand fencing, vegetative plantings, surveying, PED,

construction management, adaptive management, and post-construction

monitoring. Details of these refinements can be found in Appendix L. A formal risk

analysis was also performed using Crystal Ball software to refine the preliminary

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cost contingency for the initial restoration efforts (Appendix L). The baseline

project costs were then escalated to the mid-point of design, construction, and

monitoring to account for predicted expenditure timeframes (Appendix L). Based on

these refinements, the resulting fully funded cost of the NER Plan was determined

to be $689,000,000 without renourishment. A breakdown of the fully funded cost is

provided in Table 3-35.

Table 3-35 Fully Funded Cost Summary for NER Plan Initial Restoration

Project Element Fully Funded Totala

Lands & Damages $715,000

Fish & Wildlife

(Adaptive Management Plan)

$5,820,000

Breakwaters & Seawalls $2,494,000

Beach Replenishment $619,000,000

PED $30,000,000

Construction Management $31,000,000

NER Initial Restoration

Fully Funded Costs

$689,000,000

a Includes contingency; Does not include renourishment

Renourishment costs, including the mobilization/demobilization events and the cost

of dredging the sediment, were later added to the MCACES to determine the

ultimate cost of the NER Plan. Based on a total renourishment cost of

approximately $557,000,000, the fully funded cost for the NER Plan with

renourishments is approximately $1,246,000,000.

3.6.3 Significance of Ecosystem Outputs

Chapter 2 of ER 1105-2-100 requires plan formulators to consider significant

resources and significant effects when comparing and selecting alternatives.

Significance of resources and effects are derived from institutional, public, and

technical recognition. Resource significance is expanded in Section 4.2.

3.6.3.1 Institutional Significance

Significance based on institutional recognition means that the importance of an

environmental resource is acknowledged in the laws, adopted plans, and other

policy statements of public agencies, tribes, or private groups. The following

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sections discuss the specific plans, policies, and acts that support the construction of

the NER Plan (with renourishment).

Master Plan

Louisianas Comprehensive Master Plan for a Sustainable Coast (Master Plan)

identifies barrier shoreline restoration of Terrebonne Basin as a specific element of

the plan (Plan No. 3a-14). This element proposes the use of sediment dredged from

offshore sources to reestablish sustainable barrier islands and barrier headlands.

The barrier shoreline extends from Bayou Lafourche west to Raccoon Island, and

includes the Caminada Headland west of Belle Pass (CPRA, 2007). The

construction of restoration plans for Raccoon, Whiskey, Trinity, and Timbalier

Islands will directly contribute to the achievement of the States goal of restoring

the Terrebonne Basin barrier shoreline.

CWPPRA

While the Federal government has been concerned with and involved in Louisianas

coastal land loss problem for decades, enactment of CWPPRA in 1990 marked the

first Federal statutory mandate for restoration of Louisianas coastal wetlands. The

CWPPRA mandates preparation of an annual Priority Projects List (PPL). These

lists consist of projects that address gulf and inland shoreline protection, sediment

and freshwater diversions, terracing, vegetative plantings, marsh creation,

hydrologic restoration, marsh management, and barrier island restoration.

There have been two separate CWPPRA projects proposed for Raccoon Island, TE29 and TE-48. As previously stated, the TE-29 project, which was completed in July

1997, included the construction of eight segmented breakwaters along the eastern

end of the island. Phase A of TE-48, which included the construction of eight

additional segmented breakwaters and a terminal groin, was completed in

September of 2005. The terminal groin, which was constructed on the eastern end

of the island, was intended to prevent longshore currents from scouring

accumulated sediment behind the breakwater field. Phase B, which is currently in

the pre-construction phase, will include the construction of a 53-acre marsh along

the backside of the island. The resilience of Raccoon Island Plan E is partially due

to the existing breakwaters from both CWPPRA projects.

Two CWPPRA projects have been authorized and constructed on Whiskey Island

since 2000: TE-27 and TE-50. The objective of the TE-27 was to close the breach at

Coupe Nouvelle and thereby fortify the Gulf shoreline from Coupe Nouvelle to the

eastern end of the island. TE-50 was recently constructed to increase the longevity

of the previous TE-27 restoration effort by increasing the islands width, providing

sand fencing, and stabilizing the restoration efforts with vegetation (LDNR, 2009).

The objective of CWPPRA project TE-24 was to close the existing breaches on

Trinity Island. The project also aimed to increase the elevation and width of the

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island, and to restore the back barrier marshes. TE-24 was successfully completed

in June of 1999.

Timbalier Island was the focus of two CWPPRA projects; TE-18 and TE-40. TE-18

was a planting demonstration project that included the installation of sand fencing

along 7,400 ft of shoreline on the island. The goal of the project was to increase the

elevation of the island and the associated vegetative covering. The project was

completed in July of 1996. The second CWPPRA project, TE-40, was completed in

December of 2004. The project restored approximately 2.2 miles of beach and dune

and created a marsh platform. Approximately 11,500 ft of sand fencing were later

added to the Study area.

The authorization of the seven CWPPRA projects on Raccoon, Whiskey, Trinity, and

Timbalier Island proves that there is a need and a desire to restore and maintain

the islands on both a State and Federal level. Although the NER Plan is not a

CWPPRA project, it directly contributes to achieving the goals and objectives of

CWPPRA by restoring four critical barrier islands in the Isle Dernieres and

Timbalier Reaches.

Endangered Species Act of 1973

The Endangered Species Act of 1973, as amended, requires the designation of

critical habitat for all threatened and endangered species. Critical habitat is habitat

essential for the conservation or recovery of an endangered or threatened species.

In the July, 2001 Final Rule (Federal Register, Vol. 66, No. 132), the USFWS

designated Raccoon, Whiskey, Trinity, East, and Timbalier Islands as critical

habitat for wintering populations of the endangered piping plover. The construction

of the NER Plan, which will restore four of the five islands mentioned above, will

create additional habitat for the piping plover and will sustain this habitat beyond

the year of disappearance predicted for the FWOP conditions.

Terrebonne Parish Coastal Zone Management Program

One of the specific goals outlined by the Terrebonne Parish Coastal Zone

Management (TPCZM) Program is to maintain the integrity of the Isles Dernieres

for the protection of interior marshes, local infrastructure, and coastal communities.

In order to meet this goal, the CZM developed three policies, one of which is to

encourage the use of barrier island restoration practices to maintain or increase

island elevation, preventing washover during storms and further deterioration of

the islands (TPLCPAC, 2000). The construction Raccoon Plan E, Whiskey Plan C,

Trinity Plan C, and Timbalier Plan E will increase the width and elevations of the

existing islands through the restoration and creation of the beach and dune

components. The plans also include the construction of back-barrier marshes to

catch washover sediment during storm events.

Relationship to USACE Campaign Plan

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As previously stated, the second goal of the USACE Campaign Plan is to deliver

enduring and essential water resource solutions through collaboration with

partners and stakeholders. Construction of the NER Plan will achieve this goal

because it prolongs the life and restores the habitat value of four critical islands

(Raccoon, Whiskey, Trinity, and Timbalier Island) in the barrier island system.

Restoration of the islands is expected to increase storm surge and wave height

mitigation, which will assist in Gulf Coast recovery. The NER Plan was also

designed to endure a Katrina/Rita event, an Ike/Gustav event, and a 50-year design

storm plus an additional five years of background erosion and subsidence.

Furthermore, this project is a collaborative effort between CPRA, USFWS, NOAA,

USACE, and public stakeholders.

3.6.3.2 Public Significance

Public recognition indicates that a certain segment of the general public considers

the resource significant. The following sections discuss public input in support of

the NER Plan (with renourishment).

NEPA Public Scoping Meeting

The USACE published a scoping meeting announcement to request comments

regarding the scope of the Terrebonne Basin Barrier Shoreline Restoration Study.

The meeting was held on Tuesday, February 10, 2009, in Houma, Louisiana. A

total of 74 specific comments were expressed. The comments were categorized

according to their applicability to the SEIS. SEIS categories include purpose and

need, alternatives, affected environment, environmental consequences and

consultation, coordination, and compliance with regulations.

There were a considerable number of comments that stressed the need to protect

the barrier islands in the area: Our barrier islands are our first line of defense both

for storm surge protection and protection of the estuaries. This is the first study

that focuses strictly on our barrier island chain from Belle Pass westward over for

the Terrebonne and Lafourche or Lafourche Basin barrier island chain and

everybody wants this project (USACE, 2009). Several respondents stressed the

urgency of project implementation. The NEPA Scoping Meeting is discussed in

greater detail in Section 6.0.

National Audubon Society

The National Audubon Society has designated the Isles Dernieres and Timbalier

Islands as Important Bird Areas (IBA). The remote nature of these islands makes

them extremely valuable to nesting, wintering, and migrant birds since they are

rarely disturbed by anthropogenic activities or large populations of mammalian

predators. The National Audubon Society identified coastal erosion and sea level

rise as the primary threats to the IBA (National Audubon Society, 2010). The

construction of the restoration plans for Raccoon, Whiskey, Trinity, and Timbalier

Islands will help to sustain bird populations in the IBA by creating additional

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habitat acres for bird populations and by preserving the 344 acres of existing

mangrove stands on Raccoon and Whiskey Island.

3.6.3.3 Technical Significance

Technical recognition of a resource is based on technical criteria. The following

sections discuss the technical significance of the NER Plan (with renourishment).

Status and Trends

There is currently no dune habitat on Raccoon or Whiskey Islands. Simulated

erosion of the islands for FWOP conditions reveals that the supratidal and

intertidal habitat for Raccoon Island is expected to disappear by TY30 and TY40,

respectively. For Whiskey, supratidal and intertidal habitat is expected to

disappear by TY17 and TY31, respectively. The dune, supratidal, and intertidal

habitats on Trinity are expected to disappear by TY20, TY33, and TY40,

respectively. Although Timbalier is expected to retain some intertidal habitat after

TY50, the dune and supratidal habitat are expected to disappear by TY20 and

TY46, respectively.

The NER Plan (with renourishment) will create and sustain dune habitat until at

least TY41 for each island and supratidal and intertidal habitat beyond the 50-year

period of analysis. By extending the life of each habitat type on the island, the NER

Plan is technically significant.

Limiting Habitat

The USFWS designated Whiskey Island as critical habitat for wintering

populations of the endangered piping plover. The island also hosts healthy

populations of brown pelicans, which were recently removed from the Threatened

and Endangered Species List. The construction of Whiskey Island Plan C will

create additional habit for the piping plover and brown pelicans and will sustain

this habitat beyond the year of disappearance predicted for the FWOP conditions.

Wave Height and Storm Surge Mitigation

In 2003, Stone et al. conducted a pilot study to evaluate the impacts of barrier

islands and wetlands deterioration on storm surge and wave energy along the Isles

Dernieres and Timbalier Islands. The study compared storm surge elevations and

significant wave heights for historic conditions (1950), recent conditions (the 1990s),

and anticipated future conditions (2020). When comparing 1950 to 1990, the

modeling outputs revealed that the marsh shoreline directly behind the islands

experienced a 10-ft increase while the remaining portion of the Study Area

experienced a 6-ft increase in storm surge. The model also revealed a 4 to 5-ft

increase in significant wave height along the marsh shoreline. This considerable

increase in storm surge and wave height was directly attributed to the 24% loss of

barrier island and marsh landmass that occurred during the period of analysis

(1950-1990). The cumulative effects of the increased wave height and storm surge

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resulted in the inundation of an additional 80,000 acres of landmass within the

Study Area (Stone et al 2003).

Between 1990 and 2020, the model also predicted considerable increases in storm

surge elevations and significant wave heights. Storm surge increases of 10 ft to 12

ft (and greater) were found along the bay fringing the marsh north of the Isles

Dernieres. The marshes flanking Terrebonne Bay experienced surge increases of 1

to 6 ft. Significant wave height increased by up to 5 ft along the Isles Dernieres and

the marsh shoreline behind the islands while increases along Timbalier island

ranged from 6 to 8 ft. Due to the collective effects of increased wave height and

storm surge elevation, it was predicted that a Class 3 hurricane would inundate an

additional 35,000 acres of landmass in 2020 when compared to the 1990s (Stone et

al 2003).

The authors of the study concluded that the physical loss of the Isles Dernieres and

Terrebonne Islands and associated marshes has resulted and will continue to result

in increased storm surge elevations and significant wave heights (Stone et al 2003).

Although the authors of the study did not examine the incremental impacts of

individual islands on wave height and storm surge mitigation, it can reasonably be

inferred that the NER Plan will reduce weather-induced erosion on the marshes

north of Raccoon, Whiskey, and Trinity Islands.

3.6.4 Acceptability, Completeness, Effectiveness, and Efficiency

Acceptability

The NER Plan is implementable from a technical, environmental, economic,

financial, political, legal, institutional, and social perspective. Furthermore, the

USACE and CPRA find the plan satisfactory. Therefore, the NER Plan (with

renourishment) is acceptable to the Federal sponsor as well as the non-Federal

sponsor. The NER Plan was selected by an interagency and interdisciplinary team.

The Terrebonne Parish CZM also finds the four-island NER Plan acceptable.

Completeness

When selecting the NER Plan, the PDT considered a number of factors beyond its

control including real estate, operation and maintenance, monitoring, and

sponsorship factors. These factors were considered because of their potential

impacts on the realization of the NER Plan.

In order to define property ownership, required estates, and potential relocations, a

Real Estate Plan (REP) was developed specifically for the NER Plan (Appendix J).

An Adaptive Management Plan was developed to describe the post-construction

monitoring activities proposed for the NER Plan, including costs and duration of the

activities (Appendix I). Operation and Maintenance of the alternatives was

considered during plan formulation, particularly for the proposed hard structures

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(see Section 3.6.9) and renourishment (see Section 3.6.1). Sponsorship factors,

particularly related to the non-Federal sponsor, were considered in the analysis

(Appendix L). The cost risk analysis also quantifies external risks associated with

fuel prices, severe weather downtime, pipeline length, bidders risk, steel prices, and

hurricane demobilizations. Risks and Uncertainties associated with numerical

models and relative sea-level rise are discussed in Section 3.8.

Since the above-mentioned external factors and risks were considered during the

selection of the NER Plan, the Federal and non-Federal sponsors agree that the

plan is complete.

Effectiveness

Effectiveness is the extent to which an alternative plan alleviates the specified

problems and achieves the specified opportunities. The problems that were

identified for the Terrebonne Basin Barrier Shoreline include the following:

1. Land loss due to erosion threatens the geomorphic and hydrologic barrier

systems

2. Loss of barrier island/headland ecosystem habitat

3. Freshwater wetlands are impacted by increased salinity

4. Longshore sediments are significantly reduced, limiting the ecosystems

ability to be self-sustaining

Problem #1: Land loss would be reversed on Raccoon, Whiskey, Trinity, and

Timbalier Islands with the construction of the NER Plan. Immediately after

construction (TY1), the NER Plan will add 3,283 acres of habitat (dune, intertidal,

and supratidal) to the existing island footprints of Raccoon, Whiskey, Trinity, and

Timbalier Islands, increasing the total size of the islands to 5,840 acres. This

includes approximately 472 acres of dune, 4,320 acres of supratidal habitat, and

1,048 acres of intertidal habitat. The dimensions of the island template for Raccoon

Plan E, Whiskey Plan C, Trinity Plan C, and Timbalier Plan E will provide

geomorphologic form and ecologic function (as defined in Section 3.3.2.2.1) plus an

additional 25, 5, 5, and 25 years of advanced fill, respectively. The island templates

are expected to provide incidental wave dampening effects and storm surge

mitigation landward of the island. The remaining islands in the Isles Dernieres

and Timbalier Island Reaches will continue to erode at their current rate and will

provide diminishing protection from waves and storm surge. However, Whiskey

Island will benefit from additional sediment placed on Trinity Island due to

longshore drift. Similarly, Raccoon Island (the western-most island in the NER

Plan) will benefit from sediment placed on Whiskey Island. Sediment from

Timbalier Island is lost in Cat Island Pass and thus does not contribute to the

islands in the Isles Dernieres.

Problem #2: Construction of the NER Plan (with renourishment) will create an

additional 2883 AAHUs on the existing island footprints, increasing the total

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ecosystem habitat benefits of Raccoon, Whiskey, Trinity, and Timbalier Islands to

3558 AAHUs. For the FWOP conditions on Raccoon Island, supratidal and

intertidal habitat is expected to disappear by TY30 and TY40, respectively.

Supratidal and intertidal habitat on Whiskey Island is expected to disappear by

TY17 and TY31, respectively. There is currently no dune habitat on either island.

If no action is taken, the dune, supratidal, and intertidal habitat on Trinity Island

will disappear by TY20, TY33, and TY40, respectively. Timbalier Island will retain

only 2 acres of intertidal habitat at TY50 and will loose all dune and supratidal

habitat by TY20 and TY46, respectively. The NER Plan (with renourishment) will

create and sustain dune habitat for each island beyond TY40 and supratidal and

intertidal habitat beyond the 50-year period of analysis. Furthermore, the NER

Plan is expected to mitigate habitat loss of the mainland directly bay-ward of the

islands. Habitat loss of the remaining islands in the Isles Dernieres and Timbalier

Island Reaches will continue at its current rate (see Table 3-19).

Problem #3: While the NER Plan is expected to create some localized reductions of

saltwater intrusion into the freshwater marshes north of Isle Dernieres and

Timbalier Island reaches, the impacts are expected to be minimal. Furthermore,

the extent of these benefits is extremely difficult to quantify. To evaluate the role of

the islands and their intervening passes in open water circulation and turbulent

mixing will require installation of long-term monitoring instruments.

Problem #4: Sediment transport along the Isles Dernieres is complex given its

fragmented nature (Georgiou et al., 2005). Overall, sediment moves in a westerly

direction along the Isles Dernieres island reach, although local bidirectional

transport occurs on Trinity and Whiskey Islands. Sediment movement around

Whiskey Pass is largely nonexistent. Within Whiskey Island, longshore sediment

transport is bi-directional. Along the east flank of the island net transport is

approximately 5,000 cy per year and directed east toward Whiskey Pass. However,

net transport along the center of the island is westward toward Caillou Bay and

Raccoon Island and increases to approximately 80,000 cy per year (Stone and

Zhang, 2001). Toward the west end of Whiskey Island the westerly net transport

decreases to approximately 50,000 cy per year. This amount of sediment enters

Caillou Bay. Longshore sediment transport on the east end of Raccoon Island is

approximately 10,000 cy per year and directed west. Depths within Caillou Bay

between Raccoon Island and Whiskey Island range from 4 ft NAVD 88 to 7 ft NAVD

88 and are less than the depth of closure of 10.5 ft NAVD 88. This indicates that

this area is within the zone of active sediment transport and up to 10,000 cy per

year may be bypassed from Whiskey Island across Caillou Bay to Raccoon Island.

Based on this analysis of existing sediment transport data, it is concluded that after

beach fill is placed on Whiskey Island during construction of the NER Plan, some of

the losses associated with profile equilibration and background erosion along

Whiskey Island will be bypassed across Caillou Bay to feed Raccoon Island. Since

Raccoon Island is considered a valuable wildlife habitat along with Whiskey Island

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(Isles Dernieres Barrier Islands Wildlife Refuge), maintaining adequate areas of

healthy beach, dune, and marsh is particularly important. Restoration of Whiskey

Island and subsequent longshore transport and bypass to the west will complement

the TE-29 and TE-48 projects on Raccoon Island (NRCS, 2007), and will supplement

the existing CWPPRA investments.

According to Georgiou et al. (2005), net sediment movement along the Timbalier

Islands is to the west, and the rate increases from east to west. This pattern

suggests that sand eroded from the eastern flank and is deposited along the west

flank of the barrier as well as in Cat Island Pass (Georgiou et al., 2005). Therefore,

longshore drift of sediment placed on Timbalier Island will not likely feed the

islands in the Isle Dernieres reach.

Opportunities for ecosystem restoration in the Terrebonne Basin Barrier Shoreline

include:

1. Increase the longevity of the barrier island geomorphic form and ecological

function

2. Improve the habitat value of the barrier island

3. Increase sediment into the longshore transport process

Opportunity #1: The NER Plan would increase the longevity of the geomorphic

form and ecologic function of Raccoon, Whiskey, Trinity, and Timbalier Island by

restoring the beach, dune, and marsh components of each island. The minimal

dimensions of these components were defined through analysis of historical

planforms and storm erosion modeling. Raccoon Plan E, Whiskey Plan C, Trinity

Plan C, and Timbalier Plan E maintains these minimal dimensions even after being

subjected to a number of design storms (see Section 3.3.2.2.1), plus an addition 5

years of advanced fill for Plan C and 25 years for Plan E. Vegetative plantings,

herbivory control, and sand fencing also contribute to restoring the geomorphic form

and ecologic function of the island.

Opportunity #2: As previously stated, construction of the NER Plan (with

renourishment) will create an additional 2883 AAHUs on the existing island

footprints, increasing the total ecosystem habitat benefits of Raccoon, Whiskey,

Trinity, and Timbalier Islands to 3558 AAHUs. For the FWOP conditions on

Raccoon Island, supratidal and intertidal habitat is expected to disappear by TY30

and TY40, respectively. Supratidal and intertidal habitat on Whiskey Island is

expected to disappear by TY17 and TY31, respectively. There is currently no dune

habitat on either island. If no action is taken, the dune, supratidal, and intertidal

habitat on Trinity Island will disappear by TY20, TY33, and TY40, respectively.

Timbalier Island will retain only 2 acres of intertidal habitat at TY50 and will loose

all dune and supratidal habitat by TY20 and TY46, respectively. The NER Plan

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(with renourishment) will create and sustain dune habitat for each island beyond

TY40 and supratidal and intertidal habitat beyond the 50-year period of analysis.

Opportunity #3: The achievement of this opportunity was addressed in the

discussion of Problem #4. Based on the analysis of existing sediment transport

data, it is concluded that after beach fill is placed on Whiskey Island during

construction of the NER Plan, some of the losses associated with profile

equilibration and background erosion along Whiskey Island will be bypassed across

Caillou Bay to feed Raccoon Island. Restoration of Whiskey Island and subsequent

longshore transport and bypass to the west will complement the TE-29 and TE-48

projects on Raccoon Island (NRCS, 2007), and will supplement the existing

CWPPRA investments.

Efficiency

The NER Plan (with renourishment), was evaluated as a stand-alone alternative in

the CE/ICA analysis. The results from the IWR output confirmed that the NER

Plan was both cost-effective and a Best Buy.

3.6.5 Sustainability

The LCA TBBSR Study was identified in the LCA 2004 report as a restoration

feature that could be implemented in the near-term that addresses the most critical

needs of the Louisiana coastline. As indicated in the LCA 2004 report, the design

and operation of the LCA TBBSR Study feature would maintain the opportunity for,

and support the development of large-scale, long range comprehensive coastal

restoration. The Study is synergistic with future restoration by maintaining or

restoring the integrity of the estuaries coastline, upon which all future restoration

is dependent. The NER Plan will work in concert with other LCA projects such as

BUDMAT, CWPPRA, and CIAP features, in addition to other current and future

projects developed under the Louisiana Coastal Comprehensive Plan, to improve

the sustainability of the Terrebonne Basin Barrier Shoreline.

As a result of the LCA TBBSR Study, there is a substantial improvement in terms

of resource sustainability within the Study area provided by the NER Plan

compared to the Future Without Project conditions. While much of the constructed

acreage created under the NER Plan will decrease by the end of the period of

analysis, the net effect of the plan will be to prevent the loss of Raccoon, Whiskey,

Trinity, and Timbalier Islands. If no actions are taken, the remaining habitat acres

on Raccoon Island (239) and Whiskey Island (820 acres) is expected to disappear by

TY40 and TY31, respectively (i.e. all dune, supratidal, and intertidal habitat will be

gone). This includes the existing critical mangrove habitat and the back-barrier

marsh created by CWPPRA project TE-48 on Raccoon and TE-50 on Whiskey. The

remaining habitat on Trinity Island (673 acres) would disappear by TY40 and only 2

acres of intertidal habitat would remain on Timbalier at TY50.The majority of this

loss would be prevented with implementation of the NER Plan. The plan also meets

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the major restoration objectives of restoring the geomorphic form and ecologic

function of the barrier islands and of restoring and improving essential habitats for

fish, migratory birds, and other terrestrial and aquatic species for the 50 year

period of analysis.

The restoration of the four islands would alter the tidal prism, thereby reducing the

formation of any additional tidal passes as well as closing or narrowing existing

passes and breaches, protecting and preserving the interior marsh habitats which

would quickly erode without the protection of the sand shoreline.

3.6.6 Components

The following sections detail the proposed templates for each of the four island

plans in the NER Plan.

3.6.6.1 Whiskey Island Plan C

Whiskey Island Plan C proposes a dune height of +6.4 ft NAVD 88 with a dune

crown width of 100 ft. The dune elevation takes into account that there will be

approximately 0.4 ft of vertical adjustments (sea level change, subsidence, and

compaction) occurring during the first six months after construction. At the end of

the six-month period, the dune should reach the design elevation of +6.0 ft NAVD

88. The slopes of the beach and dune are set 60:1 and 30:1 (horizontal to vertical),

respectively.

The marsh fill is proposed on the landward side of the dune at an elevation of +2.4

ft NAVD 88. Although the design elevation for the marsh is +1.6 ft NAVD 88, the

marsh will be constructed at a higher elevation to account for initial vertical

adjustments.

The plan will utilize beach/dune material from the Ship Shoal borrow area and

marsh material from Whiskey 3a borrow area. An access channel will be excavated

along the northern perimeter of the island to facilitate fill placement during

construction. Fill quantities for the initial construction of the dune/beach and marsh

components of Whiskey Plan C are 8.3 million and 0.6 mcy, respectively. For the

dune area, the material will be pumped from the dredge to the beach. The material

will then be worked on the beach by bulldozers and front-end loaders. For the

marsh area, the material will be pumped from the offshore borrow site.

Containment dikes will be constructed around the perimeter. Sediment for the

containment dikes will be dredged from existing material inside the marsh creation

area. These operations will be completed in a manner that will minimize turbidity

of the water at the dredge site and the discharge site. Figure 3-13 presents the plan

view of Whiskey Plan C.

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Approximately 18,000 ft of sand fencing will be installed. The sand fences are

porous barriers that reduce wind speed along the coast such that sand being

transported by the wind accumulates on the downwind side of the fence. The sand

fences will promote deposition of windblown sand, create dune features, reduce

trampling of existing dunes by beach visitors, and protect vegetative plantings.

Vegetative plantings will include a variety of native species. The recommended

planting density is no greater than 8-ft centers.

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Figure 3-13. Whiskey Island Plan C

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3.6.6.2 Trinity Island Plan C

Trinity Plan C proposes a dune height of +6.4 ft NAVD 88 with a dune crown width

of 100 ft. The slopes of the beach and dune are set 60:1 and 30:1 (horizontal to

vertical), respectively. The marsh fill is proposed on the landward side of the dune

at an elevation of +2.5 ft NAVD 88, which is slightly higher than the dune elevation

at Whiskey. Due to the existing topography of Trinity Island, the required marsh

fill thickness is greater and thus results in a higher compaction rate. As with

Whiskey Island, the dune and marsh elevations account for vertical adjustments

occurring after the first six months of construction.

Immediately after construction (TY1), the Trinity Plan C will add 585 acres of

habitat (dune, intertidal, and supratidal) to the existing 564-acre island footprint,

increasing the size of the island to 1,149 acres. This includes 129 acres of dune, 456

acres of supratidal, and 564 acres of intertidal habitat.

Trinity Plan C will utilize beach/dune material from Ship Shoal and marsh material

from the Whiskey 3A borrow area. An access channel will be excavated along the

northern perimeter of the island to facilitate fill placement during construction. Fill

quantities for the dune/beach and marsh components of Trinity Plan C are 3.8

million and 3.8 mcy, respectively. For the dune area, the material will be pumped

from the dredge to the beach. The material will then be worked on the beach by

bulldozers and front-end loaders. For the marsh area, the material will be pumped

from the offshore borrow site. Containment dikes will be constructed around the

perimeter. Sediment for the containment dikes will be dredged from existing

material inside the marsh creation area. These operations will be completed in a

manner that will minimize turbidity of the water at the dredge site and the

discharge site. Figure 3-14 presents the plan view of Trinity Plan C.

Approximately 22,500 ft of sand fencing will be installed to promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach

visitors, and protect vegetative plantings. Vegetative plantings will include a

variety of native species. The recommended planting density is no greater than 8-ft

centers.

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Figure 3-14. Trinity Island Plan C

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3.6.6.3 Raccoon Island Plan E with Terminal Groin

Raccoon Plan E proposes a dune height of +7.7 ft NAVD 88 with a dune crown

width of 100 ft. The dune elevation is considerably higher than that of Trinity and

Whiskey because the plan is design to withstand 25 years of additional back ground

erosion rather than just 5 years. Furthermore, the thickness of the 25-year plan

(Plan E) results in a higher compaction rate.

The slopes of the beach and dune are set 60:1 and 30:1 (horizontal to vertical),

respectively. The marsh fill is proposed on the landward side of the dune at an

elevation of +3.7 ft NAVD 88. As with the dune elevation, the marsh elevation is

higher than that of Whiskey and Trinity because it is designed withstand a longer

duration of background erosion.

Immediately after construction (TY1), the Raccoon Plan E will add 554 acres of

habitat (dune, intertidal, and supratidal) to the existing 235-acre island footprint,

increasing the size of the island to 789 acres. This includes 63 acres of dune, 688

acres of supratidal, and 38 acres of intertidal habitat.

Eight detached and segmented breakwaters were constructed as part of a CWPPRA

project (TE-29) in 1997. The breakwaters were installed to reduce shoreline retreat,

promote sediment deposition along the beach, and to protect seabird habitat. Due

to the success of the TE-29 breakwaters, eight additional breakwaters were

constructed as part of a separate CWPPRA project (TE-48) that was completed in

1997. The breakwaters were installed west of the original breakwaters. TE-48 also

included the creation of approximately 60 acres of emergent and intertidal backbarrier marsh.

Raccoon Plan E was designed to complement the intertidal marsh created as part of

TE-48. Plan E was also designed to avoid approximately 58 acres of existing

mangroves immediately adjacent to and gulfward of TE-48 (Figure 3-15).

A terminal groin will also be constructed as part of Raccoon Island Plan E. The

terminal groin will be approximately 1200 ft long and 75 ft wide and will be

installed at the western terminus of the template to prevent sediment migration out

of the Isle Dernieres system.

Fill quantities for the dune/beach and marsh components of Raccoon Plan E are 5.4

million and 4.6 mcy, respectively. An access channel will be excavated along the

northern perimeter of the island to facilitate fill placement during construction. The

plan will utilize beach/dune material from Ship Shoal and marsh material from the

Raccoon Island TE-48 borrow area. However, the borrow area does not have enough

material to construct the marsh in its entirety. Therefore, approximately 2.8 mcy of

sand will be dredged from Ship Shoal to provide a base layer for the marsh. The

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marsh material from the Raccoon Island TE-48 borrow area will be deposited on the

sand material to provide an adequate foundation for the marsh.

For the dune area, the material will be pumped from the dredge to the beach. The

material will then be worked on the beach by bulldozers and front-end loaders. For

the marsh area, the material will be pumped from the offshore borrow site.

Containment dikes will be constructed around the perimeter. Sediment for the

containment dikes will be dredged from existing material inside the marsh creation

area. These operations will be completed in a manner that will minimize turbidity

of the water at the dredge site and the discharge site. Figure 3-15 presents the plan

view of Raccoon Plan E and the proposed terminal groin.

Approximately 12,200 ft of sand fencing will be installed to promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach

visitors, and protect vegetative plantings. Vegetative plantings will include a

variety of native species. The recommended planting density is no greater than 8-ft

centers.

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Figure 3-15. Raccoon Island Plan E with Terminal Groin

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3.6.6.4 Timbalier Island Plan E

Timbalier Plan E proposes a dune height of +7.1 ft NAVD 88 with a dune crown

width of 100 ft. The slopes of the beach and dune are set 60:1 and 30:1 (horizontal

to vertical), respectively. The marsh fill is proposed on the landward side of the

dune at an elevation of +3.2 ft NAVD 88. As with Raccoon Island Plan E, the

elevations of the plan are larger than that of Trinity and Whiskey because it is

designed to withstand a longer period of background erosion. Furthermore, the

larger plans are thicker and thus exhibit higher compaction rates.

Immediately after construction (TY1), the Timbalier Plan E will add 1675 acres of

habitat (dune, intertidal, and supratidal) to the existing 955-acre island footprint,

increasing the size of the island to 2,630 acres. This includes 215 acres of dune,

2346 acres of supratidal, and 69 acres of intertidal habitat.

Fill quantities for the dune/beach and marsh components of Timbalier Plan E are

10.7 million and 9.1 mcy, respectively. An access channel will be excavated along

the northern perimeter of the island to facilitate fill placement during construction.

Timbalier Plan E will utilize beach/dune material from South Pelto and marsh

material from Whiskey 3A (marsh material). However, the marsh borrow areas do

not have adequate material to construct the marsh in its entirety. Therefore,

approximately 8.6 mcy of sand will be dredged from South Pelto, Whiskey 3A (sandy

material), and New Cut to provide a base layer for the marsh. The marsh material

from Whiskey 3A will be deposited on the sand material to provide an adequate

foundation for the marsh.

For the dune area, the material will be pumped from the dredge to the beach. The

material will then be worked on the beach by bulldozers and front-end loaders. For

the marsh area, the material will be pumped from the offshore borrow site.

Containment dikes will be constructed around the perimeter. Sediment for the

containment dikes will be dredged from existing material inside the marsh creation

area. These operations will be completed in a manner that will minimize turbidity

of the water at the dredge site and the discharge site. Figure 3-16 presents the plan

view of Timbalier Plan E.

Timbalier Island hosts three oil and gas wells that are operated by Hilcorp Energy

Co. Based on recent conversations with Hilcorp, two of the three wells on Timbalier

are in the process of being plugged and abandoned and therefore will not require

access. The third well, SL 301 #101 is active and was recently refurbished by

Hilcorp. There is also a tank battery immediately east of the well that is still in

operation. Therefore, an access canal was incorporated into the design of the

template to facilitate barge travel from the bayward side of the island to the well

and tank battery. The canal is approximately 100 ft wide by 2,000 ft long.

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A second access canal will be provided at the western end of the island to facilitate

access to an active platform. The platform, which is operated by Phoenix

Exploration, serves as a junction point for the Tennessee Pipeline. The access

canal is approximately 100 ft wide by 550 ft long.

Approximately 35,500 ft of sand fencing will be installed to promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach

visitors, and protect vegetative plantings. Vegetative plantings will include a

variety of native species. The recommended planting density is no greater than 8-ft

centers.

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Figure 3-16. Timbalier Island Plan E

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3.6.7 Design, Environmental, and Construction Considerations

Project construction will require the hydraulic placement of beach and marsh fill

within the Study area. Inclement weather, especially tropical storms, may impact

the construction schedule. High seas may impact offshore dredging. Waves and

winds from storm events may also move debris, cultural resources, and pipelines on

the gulf floor. If during dredging, cultural resources are inadvertently discovered,

there could be impacts to the schedule and cost of the project. Additionally, dredge

availability may impact the schedule and cost of the project. The project could

potentially impact threatened and endangered species as well as species of special

interest. Therefore, all construction-related activities will be coordinated with the

USFWS as well as LDWF. During the PED process both the

mechanics/methodologies and phasing of fill placement will be analyzed and

modified with the goal to eliminate or minimize adverse impacts. The project team

includes ecologists and wildlife biologists who, in concert with agency scientists, will

endeavor to ensure the maintenance of habitat diversity and the stability of a

diverse assemblage of species. The primary metrics for this should be species

diversity and habitat area, to be evaluated during the monitoring and adaptive

management process.

3.6.7.1 Protection of Endangered Species and Species of Special Interest

3.6.7.1.1 West Indian Manatee

The West Indian Manatee, which is protected under the Marine Mammal Protection

Act of 1972 and the Endangered Species Act of 1973, is found within the Study

Area. To avoid any impacts to the West Indian Manatee, all contract personnel

associated with the Study will be informed of the potential presence of manatees

and the need to avoid collisions with manatees, which are protected under the

Marine Mammal Protection Act of 1972 and the Endangered Species Act of 1973.

All construction personnel will be required to monitor all water-related activities for

the presence of manatee(s). Temporary signs will be posted prior to and during all

construction/dredging activities to remind personnel to be observant for manatees

during active construction/dredging operations or within vessel movement zones

(i.e., work area), and at least one sign will be placed where it is visible to the vessel

operator. Siltation barriers, if used by the contractor, will be made of material in

which manatees could not become entangled, and will be properly secured per

technical specifications provided by the manufacture. If a manatee is sighted

within 100 yards of the active work zone, special operating conditions will be

implemented, including:

 No operation of moving equipment within 50 ft of a manatee;

 All vessels will operate at no wake/idle speeds within 100 yards of the work area;

and

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 Siltation barriers, if used, will be monitored and re-secured as necessary.

Once the manatee has left the 100-yard buffer zone around the work area on its own

accord, special operating conditions are no longer necessary, but careful

observations will resume. Care will also be taken to avoid entrapment of

individuals if any structure is to be installed that could be a barrier or impediment

to manatee movement

3.6.7.1.2 Piping Plovers

The barrier islands in the NER Plan are designated critical habitat for the piping

plover, an endangered species. In order to minimize impacts to this species, the

sequencing of island construction will allow these birds to temporarily relocate to

suitable habitat within the boundary of the Study. For example, the proposed beach

and dune components of Whiskey and Trinity Island will be constructed before the

marsh templates. Once the beach and dune are completed on these two islands, the

construction will begin on the marsh templates. At that point, the beaches would

begin to recover. Raccoon Island, however, would remain undisturbed during

sediment placement on Whiskey and Trinity and thus would provide suitable

habitat for displaced birds. Furthermore, East Island (which is a continuation of

Trinity Island) and East Timbalier (which is adjacent to Timbalier Island) are not

part of the proposed restoration efforts and would also provide suitable habitat for

the birds during construction. Prey species smothered by dune and beach creating

activities would re-colonize in the Study boundary within two years following

completion of construction activities (USFWS, 2010a). Therefore, by the time

construction activities commence on Raccoon Island, the benthic communities on

the Whiskey and Trinity Island beaches should be in the recovery phase.

During the PED phase, the USACE will revisit the construction sequencing to

assess the feasibility of staggering the construction of the islands such that only one

island is disturbed at any point in time. This will minimize disturbance to the

piping plover during construction and maintain an abundance of critical habitat

within the immediate vicinity of the disturbed island. By staggering the initial

construction of the islands in the NER Plan, the renourishment events would also

be staggered. However, constructing the islands in series could significantly delay

the completion of the Study.

Formal consultation on the piping plover has been conducted and the USFWS has

issued a Biological Opinion (Annex A2). The USACE has agreed to comply with the

reasonable and prudent measures (RPM) and the terms and conditions outlined in

the Biological Opinion. The following RPMs will be taken to minimize take on nonbreeding piping plovers during implementation of the NER Plan:

 A baseline piping plover survey will be conducted within the migrating and

wintering season immediately prior to initial construction within the Study

Area. As part of that survey, the project footprint should be delineated using a

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global position system (GPS) unit and appropriately marked/flagged for future

survey reference and data collection;

 A survey of the intertidal benthic prey species community shall be conducted

within the migrating and wintering season immediately prior to initial

construction, at the same time as the plover distribution surveys, in order to

establish a baseline of benthic prey species diversity and abundance.

 Piping plover monitoring surveys shall be conducted during the migrating and

wintering seasons throughout initial project construction and three consecutive

years following completion of initial construction;

 To confirm re-establishment of suitable foraging habitat for migrating and

wintering plovers, monitoring surveys of the intertidal benthic prey species

community shall be conducted each year following completion of initial

construction for three consecutive years, preferably at the same time as the bird

surveys;

 The USFWS shall be notified in writing at least 3 months prior to a

renourishment event for each island. If renourishment events are conducted

during the migrating and wintering season, piping plover monitoring surveys

shall be conducted for the duration of construction activities; and

 A comprehensive report describing the actions taken to implement the RPMs

and terms and conditions associated with this incidental take statement

(including data sheets from surveys conducted) shall be submitted to the

USFWS by June 1 of the year following completion of all required surveys.

In order to be exempt from the prohibitions of Section 9 of the Endangered Species

Act, the USACE will execute the following terms and conditions.

Requirements for Piping Plover Surveys

 The USACE will conduct a minimum of two surveys per month. If conditions

require a deviation from the recommended survey schedule, such information

will be carefully documented, including an explanation why any deviation from

the recommended schedule was deemed necessary.

 Qualified professionals with shorebird/habitat survey experience will conduct

the required survey work. Piping plover monitors will be capable of detecting

and recording locations of roosting and foraging plovers, and documenting

observations in legible, complete field notes.

 Binoculars, a global positioning system (GPS) unit, a 10-60x spotting scope with

a tripod, and the USFWS-approved survey datasheet will be used during

monitoring.

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 Negative (i.e., no plovers seen) and positive survey data will be recorded and

reported.

 Piping plover locations will be recorded with a GPS unit set to record in decimal

degrees in universal transverse mercator (UTM) North American Datum 1983

(NAD83).

 Habitat, landscape, and substrate features used by piping plovers when seen

will be recorded.

 Behavior of piping plovers (e.g., foraging, roosting, preening, bathing, flying,

aggression, walking) will be documented on the USFWS-approved survey data

sheet.

 Color-bands seen on piping plovers shall also be carefully documented.

Requirements for Surveying Benthic Prey Species

 A qualified professional with sediment/macroinvertebrate sampling experience

will conduct the required benthic prey species surveys.

 A baseline macroinvertebrate survey will be conducted at the same time of the

initial piping plover survey during the migrating/wintering season immediately

prior to construction. Additional surveys will be conducted during the

migrating/wintering season each year post-construction for three consecutive

years to determine benthic prey species recovery. Such surveys will be

conducted at the same time as the plover surveys.

 Sampling will be conducted using a basic before and after control and impact

design method. Sampling will be coordinated with piping plover foraging

observations based on low tide surveys.

 In addition to recording benthic species abundance and diversity, a qualitative

measure of sediment characteristics (sand, shell, mud) will also be recorded.

 A detailed sampling methodology will be developed in coordination with the

USFWS and LDWF prior to initiating surveys.

Reporting Requirements

 All data collected during the surveys will be incorporated into an appropriate

database, preferably one for piping plovers and one for benthic prey species.

 Annual update reports will be provided to the USFWS and LDWF by June 30 of

each calendar year once construction begins. Annual update reports will include

data sheets, maps, a copy of the database, and the progress and initial findings

of piping plover and benthic community surveys, as well as any problematic

issues that may hinder future survey efforts.

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 If the USACE foresees any problematic issues that would require a change in

the recommended survey schedule due to work conditions or project delays, the

USACE will immediately notify the USFWS to resolve/correct any such issues.

 A final comprehensive report will be provided to the USFWS and LDWF by June

30 following the third year of surveys. That final report will include an analysis

of all data results from the piping plover and benthic community surveys.

 At least six months prior to mobilization, the USACE will notify the USFWS in

writing prior to each proposed renourishment event. The notification will

include whether there are any changes in the proposed amount of renourishment

per island.

Upon locating a dead or injured piping plover that may have been harmed or

destroyed as a direct or indirect result of the proposed project, the USACE will

notifying the USFWSs Lafayette, Louisiana, Field Office (337/291-3100) and the

LDWFs Natural Heritage Program (225/765-2821). Care will be taken in handling

an injured piping plover to ensure effective treatment or disposition and in handling

dead specimens to preserve biological materials in the best possible state for later

analysis.

3.6.7.1.3 Sea Turtles

Threatened and endangered sea turtles that could be found in the Study Area

include the green sea turtle, hawksbill, Kemps ridley, leatherback, and loggerhead.

Based on professional experience and related CWPPRA project construction

methods, it is anticipated that a hydraulic cutterhead dredge and booster pump(s)

would be used to excavate sediment from the available offshore borrow area(s) and

directly transport it via a submerged sediment pipeline to the islands. It is has been

the experience of the USACE that sea turtles are typically able to avoid cutterhead

dredge intakes because the dredges move along the seabed at such a slow speed.

Sediment used to construct the containment dikes would be dredged from existing

material inside the marsh creation area rather than from offshore borrow areas.

Therefore, hydraulic cutterhead dredging operations associated with construction of

the containment dikes are not expected to adversely impact sea turtles.

3.6.7.1.4 Brown Pelican and Colonial Nesting Birds

The islands included in the NER Plan host a variety of colonial nesting waterbird

species, including the brown pelican. These species breed in high densities along the

shorelines and barrier islands of Coastal Louisiana. The following section describes

the measures that will be used to avoid impacts to brown pelicans and the colonial

nesting birds that occupy the Study Area.

Due to the duration of the construction events, avoiding critical nesting periods

altogether is not feasible under the current schedule and funding constraints.

Therefore, a combination of proactive measures, coordination, monitoring, and

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avoidance will be utilized to avoid/reduce impacts to these species. Throughout

PED, consultation will continue with the LDWF, USFWS, and NMFS on detailed

contract specifications to avoid and minimize potential impacts to the brown pelican

and colonial nesting waterbirds.

Proactive measures will be taken to prevent brown pelicans and colonial nesting

waterbirds from nesting within the Study Area prior to and during construction.

These measures may include deterrents such as propane cannons, predator decoys,

or other approved bird repellant devices. These repellent devices will be placed in

designated areas within the Study Area prior to the nesting periods. Nesting

periods are April 2 through September 15 for gulls terns, and/or black skimmers;

February 16 through August 31 for nesting wading birds (i.e., herons, egrets, nightherons, ibis, and roseate spoonbills), anhingas, and/or cormorants; and April 1

through September 14 for brown pelicans. The contractor will coordinate closely

with the LDWF, USFWS, and NMFS on the timing and placement of the deterrent

devices. The USACE understands the importance of preventing nesting activities

within the Study Area that is under constructions as there is no provision for

incidental take in the Migratory Bird Treaty Act of 1918

Prior to any work, qualified personnel will conduct surveys in all potential nesting

bird habitats within the Study boundaries that may be impacted by construction or

preconstruction activities. These surveys will be conducted for both brown pelicans

and colonial nesting waterbirds. Data collection protocols will be established

through close coordination with the LDWF, USFWS, and NMFS.

 Nesting periods are April 2 through September 15 for gulls terns, and/or black

skimmers; February 16 through August 31 for nesting wading birds (i.e.,

herons, egrets, night-herons, ibis, and roseate spoonbills), anhingas, and/or

cormorants; and April 1 through September 14 for brown pelicans.

 Nesting season surveys shall be conducted in all potential nesting bird habitats

within the Study boundaries that may be impacted by construction or

preconstruction activities during the nesting season. Portions of the Study area

in which there is no potential for project-related activity during the nesting

season may be excluded.

 Surveys for detecting new nesting activity will be completed on a daily basis

prior to movement of equipment, operation of vehicles, or other activities that

could potentially disrupt nesting behavior or cause harm to the birds their eggs

or young.

 Surveys should be conducted by walking the length of the Study area and

visually inspecting, using binoculars or spotting scope, for the presence of

shorebirds exhibiting breeding behavior. If an ATV or other vehicle is needed to

cover large Study areas, the vehicle must be operated at a speed of <6 mph, shall

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be run at or below the high tide line, and the Bird Monitor will stop at no greater

than 200-meter intervals to visually inspect for nesting activity.

 Daily summaries of shorebird/brown pelican abundance, location of the birds and

their activity (e.g., foraging, resting, nesting, courtship behavior), and

summaries of any nests observed including the number of eggs and fledglings,

shall be provided on the next business day on an approved report form.

 The Bird Monitor shall communicate the results of their survey to the contractor

daily.

 If breeding is confirmed by the presence of a scrape, eggs, or young, the Bird

Monitor will immediately notify the appropriate personnel at the LDWF and

USFWS.

If nesting occurs during construction within the Study area, the contractor shall

establish a 650-ft buffer zone around colonies containing nesting gulls, terns, and/or

black skimmers; a 1,000-ft buffer around colonies of nesting wading birds (i.e.,

herons, egrets, night-herons, ibis, and roseate spoonbills), anhingas, and/or

cormorants; and a 2,000-ft buffer around nesting colonies of brown pelicans.

 The designated buffer zones shall be posted with clearly marked signs around

the perimeter. These markings shall be maintained until nesting is completed

or terminated. In the case of solitary nesters, nesting is not considered to be

completed until all chicks have fledged.

 No construction activities, movement of vehicles, or stockpiling of equipment

shall be allowed within the buffer area unless authorized by LDWF, USFWS,

and NMFS.

 LDWF/USFWS/NMFS-approved travel corridors shall be designated and marked

outside the buffer areas. Heavy equipment, vehicles, and pedestrians may

transit past nesting areas in these corridors. However, other activities such as

stopping or turning shall be prohibited within the designated travel corridors

adjacent to the nesting site.

 Where such a travel corridor must be established within the Study Area, it shall

avoid critical areas for shorebirds (known nesting sites, designated critical

wildlife habitat, and designated critical piping plover habitat) as much as

possible, and be marked with signs clearly delineating the travel corridor from

the shorebird buffer areas described above.

If shorebird or pelican nesting occurs within the Study Area, a bulletin board will be

placed and maintained in the construction area with the location map of the

construction site showing the bird nesting areas and a warning, clearly visible,

stating the bird nesting areas are protected by the Federal Migratory Bird Treaty

Act.

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3.6.7.1.5 Blue Crabs

The construction and renourishment of the NER Plan will require a total of

46,035,718 cy of fill material from the Ship Shoal borrow area. Ship Shoal possesses

a unique benthic meiofaunal and macrofaunal community due to its sandy

substrate and water depths. A study by MMS found that the shoal was an

important spawning, hatching, and foraging habitat for populations of blue crab.

The study also found that actively spawning, hatching, and foraging blue crabs

were present in the shoal between April and October, with the highest abundance

occurring in August (Condrey and Gelpi, 2010).

The dredging activities occurring during construction and renourishment could

potentially impact blue crab communities on Ship Shoal. Direct impacts could

include physical disturbance and temporarily loss of spawning, hatching, and

foraging habitats due to alterations in water depths, turbidity, and sediment

characteristics. Indirect impacts could include the alteration of food web dynamics

through the smothering and removal of benthic prey species (Stone et al., 2009).

In order to minimize impacts to the blue crab communities during construction and

renourishment, the USACE will take the following precautions:

 Survey blue crab populations within the Ship Shoal disturbance area prior to,

during, and after construction of the NER Plan;

 Minimize dredging activities during the spawning, hatching, and foraging

season (April through October);

 Minimize the depth of dredging to prevent the formation of hypoxic zones;

and

 Phase the dredging activities such that blue crabs will have sufficient habitat

adjacent to the disturbance area for relocation.

All dredging activities will be conducted in close coordination with NMFS, USWFS,

and LDWL.

3.6.7.2 Beach and Dune Construction

A hydraulic cutterhead dredge would be used to excavate sand from the available

sand borrow areas. The sand will then be pumped through a series of booster

pumps to the beach/dune fill template via a submerged sediment pipeline.

During construction the contractor will be directed to maintain dedicated

equipment loading/unloading areas, staging areas, and access corridors to minimize

the impacts to the island. Existing mangrove habitats and prior restoration Study

areas shall be avoided by construction equipment and construction-related

activities.

Once on the beach, the sediment pipeline would run parallel to the shoreline. Frontend loaders equipped with grapple arms will be utilized in the placement and

relocation of the sediment pipeline. For segments of the fill template that have

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sufficient width, a Y-valve would be utilized to enable placement of multiple

sediment pipelines along the template. The bifurcation of the discharge pipeline will

facilitate lower discharge velocities and increased sediment retention within the fill

template. In order to minimize the impact on piping plover, the beach will be

constructed in sections to allow the birds to move to areas that are not currently

under construction.

The dredged material would be worked on the beach by bulldozers to meet the

specified template grades, slopes and widths. Construction methods may vary but it

is anticipated that sand placement along the shoreline will be controlled by

advancing a temporary sand dike several hundred ft parallel to shore ahead of the

discharge terminus. This aids in reducing initial fill losses offshore and helps

control temporary turbidity that may result from the fill placement operations.

Typically water drainage and discharges will be directed offshore into the Gulf of

Mexico or into existing marsh areas to nourish these habitats.

If construction is completed during the summer, fall, or winter months, the dune

and supratidal areas would be temporarily stabilized through aerial dispersion of

grass seed. During the first spring following construction, the dune and supratidal

areas would be planted with a more permanent combination of plants including

bitter panicum (Panicum amarum var amarum Fourchon), sea oats (Uniola

paniculata Caminada), marshhay cordgrass (Spartina patens Gulf Coast) and gulf

cordgrass (Spartina spartinae). Vegetation would be manually planted on 8-ft

centers and would provide 100% coverage of the dune and supratidal areas.

An additional 15% of the dune and supratidal swale areas will be planted with

woody species in TY2. The vegetation will be manually planted on 8-ft centers.

Woody species will include matrimony vine (Lycium barbarum), wax myrtle (Myrica

cerifera), iva (Iva imbricata), eastern baccharis (Baccharis halimifolia), and hercules

club (Zanthoxylum clava-herculis).

3.6.7.3 Back-Barrier Marsh Construction

As with the beach fill, it is anticipated that a hydraulic cutterhead dredge and

booster pump(s) would be used to excavate sediment from the available offshore

marsh borrow area(s) and directly transport it via a submerged sediment pipeline to

the marsh platform. Sediment used to construct the marsh containment dikes will

be dredged from existing material inside the marsh creation area rather than from

offshore borrow areas.

Construction operations would be done in a manner that would minimize turbidity.

Discharge and dewatering from the marsh fill shall typically be directed towards

the Gulf of Mexico including orienting discharge pipes such that the hydraulic flow

moves in a gulfward direction and locating dewatering structures on the gulf side of

the Study area. The contractor may employ other methods such as building interior

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containment dikes and creating a drainage gradient towards the gulf. If excess

turbidity occurs, the contractor will be directed to change the operating procedure to

reduce the degree of turbidity.

Herbaceous planting of the marsh template will be conducted in two phases. The

first phase will occur in the second year following construction (i.e. TY3) and will

consist of covering 50% of the platform. The remaining 50% of the platform will be

planted the following year. The species used for planting will primarily consist of

smooth cordgrass (Spartina alterniflora Vermilion). The vegetation will be

manually planted on 8-ft centers.

3.6.7.4 Construction Access Considerations

The required land based equipment including but not limited to graders, loaders,

dozers, and marsh buggy backhoes will be transported from the mainland to the

islands via barge(s). The contractor will excavate access channels from either the

Gulf of Mexico or the back bays to the islands utilizing barge mounted clamshell

dredges with temporary sidecast disposal. Exact access to the beach/dune and

marsh fill templates will be determined and coordinated during the PED phase and

will include the necessary easements. The contractor will be required to submit a

construction access plan which shall contain provisions for the restoration of any

damaged habitats.

Miscellaneous equipment to be stored on the beach may include sediment pipeline,

graders, loaders, dozers, marsh buggy backhoes, weirs, grade stakes, light towers,

fuel tanks with containment, welding machine, and temporary shanty for personnel.

Further, the contractor will locate a quarters barge in an appropriate sheltered

staging area to house the land based personnel and office facilities.

3.6.8 Real Estate Requirements

The following sections highlight the real estate considerations for the NER Plan.

Additional information is provided in the Real Estate Plan (Appendix J).

3.6.8.1 Land Acquisition

Raccoon Island

Raccoon Island is owned by the State of Louisiana and is valued highly by LDWF

because it is the largest pelican rookery in Louisiana, critical habitat for piping

plover, and it is frequented by other threatened and endangered species. The island

has a footprint which contains approximately 235 acres. Fill for the dune/beach and

marsh components will be placed directly into water bottoms owned by the State of

Louisiana as well as the upland areas owned by the State. The island is owned by

the State of Louisiana and is under the jurisdiction of the Louisiana Department of

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Wildlife & Fisheries for Isles Dernieres Barrier Island Refuge; therefore, easements

are not needed for this island, only a Grant of Particular Use.

Whiskey Island

Whiskey Island is an uninhabited island off the coast of Terrebonne Parish. Access

to the Island is only by boat. The island has a narrow beach area on the Gulf front

and broken marsh on the landside. Fill for the dune/beach and marsh components

will be placed directly into water bottoms owned by the State of Louisiana as well as

the upland areas owned by the State. The island is owned by the State of Louisiana

and is under the jurisdiction of the Louisiana Department of Wildlife & Fisheries

for Isles Dernieres Barrier Island Refuge; therefore, easements are not needed for

this island, only a Grant of Particular Use.

Trinity Island

Trinity Island has a footprint which contains approximately 887 acres. What had

been two islands for decades, and rejoined only recently appears to be successfully

maintaining itself. Fill for the dune/beach and marsh components will be placed

directly into water bottoms owned by the State of Louisiana as well as the upland

areas owned by the State and a private entity. The majority of the island is owned

by the State of Louisiana. However, a small portion of the island, approximately 30

acres, is privately owned by what appears to be one landowner. A Standard

Perpetual Beach Nourishment Easement would be acquired over these 30 acres of

private property.

Timbalier Island

Timbalier Island has a footprint which contains approximately 1,087 acres. Existing

canals are apparently routinely used to service isolated petroleum production

facilities and wells, based on evidence of recent dredging. Active gas production is

present on the northern side of the island. Fill for the dune/beach and marsh

components will be placed directly into water bottoms owned by the State of

Louisiana as well as the upland areas owned by the State and private entities. The

majority of the island is owned by the State of Louisiana. However, one end of the

island has some private ownership which is estimated to be approximately 80 acres.

The ownership of this land is heavily disputed; however, preliminary data indicates

that each of the 11 estimated tracts contain multiple owners. A Standard Perpetual

Beach Nourishment Easement would be acquired over these 80 acres of private

property.

3.6.8.2 Estates

The LDWF owns fee (excluding minerals) for Whiskey Island and Raccoon Island,

therefore, the State has sufficient interests to meet the requirements for these two

islands. The LDWF also owns fee (excluding minerals) for portions of Trinity Island

and Timbalier Island. A Grant of Particular Use (GPU) would be given from the

State to USACE for these State-owned areas. The rights delineated in the GPU will

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be similar to the language in the following standard and non-standard estates:

Perpetual Beach Nourishment Easement, Perpetual Restrictive Dune Easement,

Temporary Work Area Easement, and a Wetland Creation and Restoration

Easement. The acquisition of these specific estates over these areas is not required

because the land is owned by the State of Louisiana. Therefore, only administrative

costs would apply.

For the private property located on Trinity Island and Timbalier Island, easements

would need to be acquired. The estate anticipated to be acquired would be a

standard Perpetual Beach Nourishment Easement.

3.6.8.3 Acquisition Costs

Construction and renourishment of the NER Plan will occur on both State owned

and private properties; therefore, costs will be incurred associated with obtaining

title, mapping and right of entry for construction from the State and private

ownerships; as well as appraisals, negotiations, and the actual land costs for the

easements over the private property. Costs are estimated to be approximately

$692,000 in 2009 dollars (escalated to $715,000 in 2012).

3.6.8.4 Relocation Assistance

The Study does not displace residential, commercial or industrial facilities.

Therefore, the provisions of Title II of Public Law 91-646, as amended are not

applicable.

3.6.8.5 Mineral Exploration

Throughout the Study area of the NER Plan, several oil and gas pipelines are

present. Pipeline crossings occur within the island footprints, between the islands,

and within the vicinity of the islands inshore waters. These pipelines are used to

transport crude oil and natural gas from wells to facilities scattered throughout the

Terrebonne Basin. These lines will be identified, marked and protected during

construction and renourishment. The placement of sediment on these lines will pose

no adverse impact on the pipelines.

Although the underlying mineral right holders have the right to access the surface

of the islands to explore for minerals, it is not likely that they will do so. These

islands are part of the Terrebonne Barrier Island Refuge and to conduct mineral

explorations on the island would be inconsistent with the protection of wildlife.

Louisiana Land and Exploration (LL&E), one of the major underlying mineral right

holders, is a large landowner with property throughout south Louisiana. It is

important for this company to maintain an image that portrays it as an

environmental steward.

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In addition, the LDWF has established procedures for granting permits for

exploratory activities on its WMAs. These procedures would apply to Whiskey,

Raccoon and portions of Trinity/East Islands, as they are part of the Isles Dernieres

Barrier Islands Refuge. Below is a list of requirements from the LDWF.

The LDWF requires a request for permit be submitted in writing. A Conditions of

Letter of Permission to Conduct Seismic Activity in the State of Louisiana form

must be signed by the company proposing exploration. If the LDWF grants the

permit in accordance with regulations, there are still other actions that must be

taken prior to beginning exploration. The seismic company must request a Natural

Heritage review and submit a Notification of Beginning of Seismic Exploration

form. In addition, the company must hold a public meeting. Additionally, any

activity in the wetalnds is regulated by Section 404 of the Clean Water Act under

the purview of the USACE.

3.6.9 Operations and Maintenance Considerations

3.6.9.1 Breakwaters and Terminal Groin

The purpose of Operation and Maintenance (O&M) is to allow a project to continue

to function. For a structure such as a breakwater or a terminal groin, O&M is

required to keep the structure functioning at a certain level to provide the benefits

claimed in the analysis.

The breakwaters and terminal groin structural measures were evaluated based on a

design life of 20 years. During this time, the structures will be maintained and

repaired, if necessary. Based on information obtained through personal

communication with NRCS, one of the sixteen TE-29 and TE-48 breakwaters on

Raccoon Island had to be repaired because of structural settlement (Personal

communication, Loland Broussard of NRCS, Dec, 02, 2009). Otherwise the existing

breakwaters have performed and required little to no O&M. Costs for O&M are

projected for the applicable measure discussed in Chapter L9.

After 20 years, the effectiveness of the structural measures is projected to

substantially diminish because of the sea-level change, subsidence, and barrier

island landward migration. Maintenance of the structures to the original design

after 20 years will no longer result in the same level of function and benefits as the

original structures once provided. In order to make the breakwaters and terminal

groin functioning and beneficial after 20 years, the structures will have to be

modified and rebuilt which does not qualify as O&M.

Renourishment is also considered to be an O&M activity. Raccoon Plan E will be

renourished at TY30 by adding adequate sediment such that the dune and

supratidal beach acres would be equivalent to that of a newly constructed Plan B

template (i.e. restore a Plan B at TY30). Whiskey Plan C will require two

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renourishment intervals. The first will occur at TY20 and will include the addition

of the same amount of dune and supratidal beach habitat that was originally

created in TY1 (i.e. add a Plan C to the template at TY20). The second

renourishment interval will occur at TY40 and will include the addition of the same

amount of dune and supratidal beach habitat needed to construct a Plan B

template. Trinity Plan C will be renourished at TY25 by adding the same amount

of dune and supratidal beach habitat that was originally added in TY1 (i.e. add a

Plan C to the template at TY20). Timbalier Plan E will be renourished at TY30 by

adding adequate sediment such that the dune and supratidal beach habitat acres

would be equivalent to the acres of a newly constructed Plan B template (i.e. restore

a Plan B at TY30). No additional marsh material will be added to any of the

islands. Renourishment is discussed in further detail in Section 3.6.1.

3.6.10 Monitoring Plan and Adaptive Management

The details for post-construction monitoring and adaptive management activities

proposed for the NER Plan with estimates of cost and duration are presented in

Appendix I.

3.6.11 Effectiveness of the NER Plan in Meeting Goals and

Objectives

The barrier island restoration components of the NER Plan would achieve the

planning objectives by maximizing the barrier islands ability to provide geomorphic

and hydrologic form and ecological function over the 50 year period of analysis as

well as improve critical barrier island habitats for fish, migratory birds, and other

terrestrial and aquatic species. Sediment would be entered into the system to

supplement longshore sediment transport processes along the gulf shoreline by

mechanically introducing compatible sediment, and increasing the ability of the

restored area to continue to function and provide habitat with minimum continuing

intervention.

The NER Plan is the plan that best meets the goal of the 2004 LCA Plan to address

critical near-term needs for shoreline restoration for Terrebonne Basin through

simulating historical conditions by enlarging the barrier islands (width and dune

crest) and reducing the current number of breaches to ensure the continuing

geomorphic and hydrologic form and function of the barrier islands. The selection of

the NER Plan was based on a thorough review of existing scientific and engineering

reports, as well as geospatial, survey, and geotechnical data which reaffirmed that

the findings of the Final Programmatic Environmental Impact Statement remain

valid.

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3.6.12 Effectiveness of NER Plan in Meeting Environmental

Operating Principles

The NER Plan is also the plan that best meets the USACE Principles and

Guidelines of completeness, effectiveness, efficiency, and acceptability, as well as

the Environmental Operating Principles of environmental sustainability,

interdependence, balance and synergy, accountability, knowledge, respect, and

assessing and mitigating cumulative impacts.

3.6.13 Compensatory Mitigation Measures

No compensatory mitigation is required for this Study. As an ecosystem restoration

project, the alternatives were designed to avoid, minimize, and reduce potential

adverse environmental impacts. Any incidental temporary impacts that might be

incurred during construction would be more than offset by the net habitat value

created by the NER Plan.

3.7 RECOMMENDED COMPONENT OF CONSTRUCTION

The NER Plan cannot be constructed within WRDA 2007 authorization. In order to

identify a plan that could be constructed within WRDA authorization, the PDT

performed separate cost refinements on each island in the NER Plan using

MCACES Second Generation (MII). The original contingency was also refined using

Crystal Ball. These refinements inflated the costs of the islands, leaving Trinity

Island Plan C and Whiskey Island Plan C as the only islands plans that could be

constructed within the budget. Consequently, a separate screening process was

conducted on the two islands to select the most appropriate island as the

recommended component of construction.

A previous CE/ICA analysis revealed that both islands plans, when analyzed

separately, were cost-effective. The plans also proved to be cost-effective when

analyzed as a separate alternatives (Alternatives 11 and 12) in the Intermediate

Array. The cost-effective analysis was conducted by running the IWR platform on

an extended array that included the original ten alternatives plus the two

additional alternatives (Figure 3-17). Renourishment was not included in this

analysis. Details of the additional IWR analysis are provided in Appendix K.

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Figure 3-17 CE/ICA including Alternatives 11 and 12

Although Whiskey Plan C provides slightly fewer AAHUs than Trinity Island Plan

C (379 net AAHUs vs. 387 net AAHUs), it was determined to be the recommended

component of construction due to a number of qualitative benefits provided by the

plan. For example, Whiskey Plan C was designed to avoid approximately 286 acres

of existing mangroves on the island in order to minimize the ecologic impact during

construction. The plan will restore a total of 1,272 acres of dune, supratidal, and

intertidal habitat on the Terrebonne Basin Barrier Shoreline. Since the island is

considered a valuable wildlife habitat (Isles Dernieres Barrier Islands Wildlife

Refuge) and the LDWF is reestablishing a pelican rookery on the island,

maintaining adequate areas of healthy beach, dune, and marsh is particularly

important. The island is also a critical habitat for endangered species including the

piping plover and is a valuable stopover habitat for migratory birds.

Furthermore, Whiskey Plan C was designed to complement TE-50, which is an

existing CWPPRA project that was constructed in 2009. TE-50 created

approximately 316 acres of intertidal back-barrier marsh between the two existing

mangrove stands. Restoration of the beach and dune gulfward of TE-50 will

supplement the existing CWPPRA investment.

The barrier islands provide a critical component of the estuary structure, and are

the first line of defense against marine and weather influences. Whiskey Island is

the closest of the seven barrier islands to the critical marsh habitat located in the

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southern-most portion of Terrebonne Parish. If the island were to disappear, the

marsh habitat on the mainland would be susceptible to the direct impacts of

tropical storms and hurricanes. The implementation of Whiskey Plan C as the

recommended component of construction would also increase sediment available to

Raccoon Island because the longshore sediment movement is westward.

As seen in Table 3-19, Whiskey Island is expected to disappear considerably sooner

than the other islands in the Isles Dernieres and Timbalier Island Ranges. The

island currently lacks dune habitat. If no action is taken on the island, supratidal

and intertidal habitat is expected to disappear by TY17 and TY31, respectively

(compared to TY33 and TY40 for Trinity Island). Due to the rapidly approaching

YOD of the remaining two habitat types, Whiskey Island warrants immediate

restoration.

Immediately after construction (TY1), the recommended component of construction

will add 469 acres of habitat (dune, intertidal, and supratidal) to the existing island

footprint, increasing the size of the island to 1,272 acres.

Whiskey Plan C is an implementable and separable element of the NER Plan, is

cost effective, and is within the cost and scope of the authorization. The nonFederal sponsor fully supports Whiskey Plan C as the recommended component of

construction under the current authorization.

3.7.1 Renourishment

Once the recommended component of construction was selected, the PDT reevaluated the feasibility of renourishment on Whiskey Island Plan C. This

evaluation was conducted concurrently with that of the NER Plan (see Section

3.6.1). Based on an iterative optimization process, the PDT determined that

Whiskey Plan C would require two renourishment intervals. The first would occur

at TY20 and would include the addition of the same amount of dune and supratidal

beach habitat that was originally created in TY1 (i.e. add a Plan C to the template

at TY20). The second renourishment interval would occur at TY 40 and would

include the addition of the same amount of dune and supratidal beach habitat

needed to construct a Plan B template. No additional marsh material will be added.

The resulting habitat acres, including renourishment, are provided in Table 3-36.

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Table 3-36. Habitat Acres for Whiskey Plan C (Recommended Component of Construction) Future WithProject (FWP) Conditions

Island

Habitat

Type

Habitat Acres  FWP

TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

WhiskeyPlan C

Dune 0 65 61 57 0 65 61 61 57 51 0 57 0

Supratidal 377 830 328 223 84 496 375 344 223 209 84 387 164

Intertidal 443 377 808 828 847 834 782 769 717 693 472 461 363

Total 820 1272 1197 1108 931 1395 1218 1174 997 953 556 905 527

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The WVA Barrier Island Community Model was then used to quantify the

additional habitat benefits yielded from the two-interval renourishment plan. The

model accounts for the three habitat types, vegetation coverage, interspersion, and

surf zone impacts from hard structures. Based on the results of the WVA model,

the construction of Whiskey Island Plan C with renourishment at TY20 and TY40

would create an additional 678 AAHUs on the island (compared to 379 AAHUs for

Plan C without renourishment), thus increasing the total ecological benefit of the

island to 857 AAHUs.

3.7.2 Costs

As previously stated, the PDT performed a separate cost analysis for the

recommended component of construction using the Micro-Computer Aided Cost

Estimating System (MCACES), Second Generation (MII). A separate risk analysis

was also performed using Crystal Ball software to determine the associated cost

uncertainties and derive a cost contingency percentage to be applied to the MII cost

estimate for the recommended component of construction. The resulting fully

funded cost of the initial restoration of the recommended component of construction

was $119,000,000. This was within the maximum project cost of $180,900,000 as

authorized by WRDA 2007 and modified according to section 902 of WRDA 1986, as

amended. A breakdown of the fully funded cost is provided in Table 3-37.

Table 3-37 Fully Funded Cost Summary for the Initial Restoration of the

Recommended Component of Construction

Project Element Fully Funded Totala

Lands & Damages $67,000

Fish & Wildlife

(Adaptive Management Plan)

$5,820,000

Beach Replenishment $103,000,000

PED $5,040,000

Construction Management $5,160,000

Initial Restoration

Fully Funded Costs

$119,000,000

a Includes contingency; Does not include renourishment

Renourishment costs, including two mobilization/demobilization events (one at

TY20 and one at TY40) and the cost of dredging the sediment, were later added to

the MII to determine the ultimate cost of the recommended component of

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construction. Using a total renourishment cost of approximately $342,000,000

($157,000,000 for the TY20 renourishment and $184,000,000 for the TY40

renourishment), the ultimate cost of the recommended component of construction

with renourishment is $461,000,000. However, renourishment is considered an

O&M cost that will be fully-funded by the non-Federal sponsor and does not count

toward the maximum project cost of $180,900,000 as authorized by WRDA 2007 and

modified according to section 902 of WRDA 1986, as amended.

Despite the increase in cost due to the renourishment intervals, the additional

habitat benefits created by the renourishment of Whiskey Plan C resulted in a plan

that was still cost-effective when compared to the plans in the Intermediate Array.

Table 3-38 illustrates the calculations to determine the maximum cost within

WRDA authorization.

Table 3-38 Maximum cost including inflation through the midpoint of

construction

Authorized cost in WRDA 2007 Title VII, Section

7006 (e)(3)(A): $124,600,000

Cost Index Useda

EM 1110-2-1304 (Revised 31 Mar 2010) CWBS Feature Code 17  Beach Replenishment

Cost Index Ratio

1Q FY05 to 1Q FY10 1.22

Current Project Cost Estimateb

(Inflation applied from 10/2004 to 10/2010) $151,860,000

20% of Authorized Cost: $24,920,000

Monitoring & Adaptive Managementc:

(per WRDA 2007 Section 2039)

$5,821,200 - $967,000

= $4,854,200

Maximum Cost Limited by Section 902 B:

$151,860,000 + $24,920,000 + $4,106,600

= $180,886,600

$180,900,000 (R)

Cost without Renourishmentd $119,000,000 a The cost index applied to the current estimate through PED is derived from: EM 1110-2-1304, 30 Mar 10, Civil

Works Construction Cost Index System (CWCCIS)

b For the purposes of applying the Cost Index to WRDA Authorized Cost, each project was adjusted for inflation

from the October 2004 price levels identified in the 2004 LCA Chief’s Report, where the original project budget

estimates were developed

c Line 2 is the cost of any modifications required by law. This is derived from section 8.0 of each projects

Monitoring and Adaptive Management Plan minus the project monitoring cost found on the LCA Cost Summary

Worksheet - October 2004 Price Levels modified study cost Dec 20 2004

d Renourishment is considered an O&M cost and thus is not included in the maximum cost limited by Section 902

B.

3.7.3 Significance of Ecosystem Outputs

Chapter 2 of ER 1105-2-100 requires plan formulators to consider significant

resources and significant effects when comparing and selecting alternatives.

Significance of resources and effects are derived from institutional, public, and

technical recognition. Resource significance is expanded in Section 4.2.

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3.7.3.1 Institutional Significance

Significance based on institutional recognition means that the importance of an

environmental resource is acknowledged in the laws, adopted plans, and other

policy statements of public agencies, tribes, or private groups. The following

sections discuss the specific plans, policies, and acts that support the construction of

the recommended component of construction (with renourishment).

Master Plan

Louisianas Comprehensive Master Plan for a Sustainable Coast (Master Plan)

identifies barrier shoreline restoration of Terrebonne Basin as a specific element of

the plan (Plan No. 3a-14). This element proposes the use of sediment dredged from

offshore sources to reestablish sustainable barrier islands and barrier headlands.

The barrier shoreline extends from Bayou Lafourche west to Raccoon Island, and

includes the Caminada Headland west of Belle Pass (CPRA, 2007). The

construction of Whiskey Island Plan C will directly contribute to the achievement of

the States goal of restoring the Terrebonne Basin barrier shoreline.

CWPPRA

While the Federal government has been concerned with and involved in Louisianas

coastal land loss problem for decades, enactment of CWPPRA in 1990 marked the

first Federal statutory mandate for restoration of Louisianas coastal wetlands. The

CWPPRA mandates preparation of an annual Priority Projects List (PPL). These

lists consist of projects that address gulf and inland shoreline protection, sediment

and freshwater diversions, terracing, vegetative plantings, marsh creation,

hydrologic restoration, marsh management, and barrier island restoration.

Two CWPPRA projects have been authorized and constructed on Whiskey Island

since 2000: TE-27 and TE-50. The objective of the TE-27 was to close the breach at

Coupe Nouvelle and thereby fortify the Gulf shoreline from Coupe Nouvelle to the

eastern end of the island. TE-50 was recently constructed to increase the longevity

of the previous TE-27 restoration effort by increasing the islands width, providing

sand fencing, and stabilizing the restoration efforts with vegetation (LDNR, 2009).

The authorization of the two CWPPRA projects on Whiskey Island proves that there

is a need and a desire to restore and maintain the island on both a State and

Federal level. Although Whiskey Island Plan C is not a CWPPRA project, it directly

contributes to achieving the goals and objectives of CWPPRA by restoring a critical

barrier island in the Isle Dernieres Reach.

Endangered Species Act of 1973

The Endangered Species Act of 1973, as amended, requires the designation of

critical habitat for all threatened and endangered species. Critical habitat is habitat

essential for the conservation or recovery of an endangered or threatened species.

In the July, 2001 Final Rule (Federal Register, Vol. 66, No. 132), the USFWS

designated Raccoon, Whiskey, Trinity, East, and Timbalier Islands as critical

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habitat for wintering populations of the endangered piping plover. The construction

of Whiskey Island Plan C will create additional habit for the piping plover and will

sustain this habitat beyond the year of disappearance predicted for the FWOP

conditions.

Terrebonne Parish Coastal Zone Management Program

One of the specific goals outlined by the Terrebonne Parish Coastal Zone

Management (TPCZM) Program is to maintain the integrity of the Isles Dernieres

for the protection of interior marshes, local infrastructure, and coastal communities.

In order to meet this goal, the CZM developed three policies, one of which is to

encourage the use of barrier island restoration practices to maintain or increase

island elevation, preventing washover during storms and further deterioration of

the islands (TPLCPAC, 2000). The construction Whiskey Island Plan C will increase

the width and elevation of the island through the restoration and creation of the

beach and dune components. The plan also includes the construction of a backbarrier marsh to catch washover sediment during storm events.

Relationship to USACE Campaign Plan

As previously stated, the second goal of the USACE Campaign Plan is to deliver

enduring and essential water resource solutions through collaboration with

partners and stakeholders. Although the recommended component of construction

will restore a single island, it achieves this goal because it prolongs the life and

restores the habitat value of a critical island (Whiskey Island) in the barrier island

system. Restoration of the island is expected to increase storm surge and wave

height mitigation, which will assist in Gulf Coast recovery. Because the

recommended component of construction restores the geomorphologic form and

ecologic function of the island, it is designed to endure a Katrina/Rita event, an

Ike/Gustav event, and a 50-year design storm plus an additional five years of

advanced fill. Furthermore, this Study is a collaborative effort between CPRA,

USFWS, NOAA, USACE, and public stakeholders.

3.7.3.2 Public Significance

Public recognition indicates that a certain segment of the general public considers

the resource significant. The following sections discuss public input in support of

the recommended component of construction (with renourishment).

NEPA Public Scoping Meeting

The USACE published a scoping meeting announcement to request comments

regarding the scope of the Terrebonne Basin Barrier Shoreline Restoration Study.

The meeting was held on Tuesday, February 10, 2009, in Houma, Louisiana. A

total of 74 specific comments were expressed. The comments were categorized

according to their applicability to the SEIS. SEIS categories include purpose and

need, alternatives, affected environment, environmental consequences and

consultation, coordination, and compliance with regulations.

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Although there were no specific comments related to Whiskey Island, there were a

considerable number of comments that stressed the need to protect the barrier

islands in the area: Our barrier islands are our first line of defense both for storm

surge protection and protection of the estuaries. This is the first study that focuses

strictly on our barrier island chain from Belle Pass westward over for the

Terrebonne and Lafourche or Lafourche Basin barrier island chain and everybody

wants this project (USACE, 2009). Several respondents stressed the urgency of

project implementation. The NEPA Scoping Meeting is discussed in greater detail

in Section 6.0.

National Audubon Society

The National Audubon Society has designated the Isles Dernieres and Timbalier

Islands as Important Bird Areas (IBA). The remote nature of these islands makes

them extremely valuable to nesting, wintering, and migrant birds since they are

rarely disturbed by anthropogenic activities or large populations of mammalian

predators. The National Audubon Society identified coastal erosion and sea level

rise as the primary threats to the IBA (National Audubon Society, 2010). The

construction Whiskey Island Plan C will help to sustain bird populations in the IBA

by creating additional habitat acres for bird populations and by preserving the 286

acres of existing mangrove stands on the island.

3.7.3.3 Technical Significance

Technical recognition of a resource is based on technical criteria. The following

sections discuss the technical significance of the recommended component of

construction (with renourishment).

Status and Trends

Simulated erosion of the islands for FWOP conditions reveals that the supratidal

and intertidal habitat is expected to disappear by TY17 and TY31, respectively.

There is currently no dune habitat on the island. The recommended component of

construction (with renourishment) will create and sustain dune habitat until TY50

and supratidal and intertidal habitat beyond the 50-year period of analysis. By

extending the life of each habitat type on the island, the recommended component of

construction is technically significant.

Limiting Habitat

The USFWS designated Whiskey Island as critical habitat for wintering

populations of the endangered piping plover. The island also hosts healthy

populations of brown pelicans, which were recently removed from the Threatened

and Endangered Species List. The construction of Whiskey Island Plan C will

create additional habit for the piping plover and brown pelicans and will sustain

this habitat beyond the year of disappearance predicted for the FWOP conditions.

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Wave Height and Storm Surge Mitigation

In 2003, Stone et al. conducted a pilot study to evaluate the impacts of barrier

islands and wetlands deterioration on storm surge and wave energy along the Isles

Dernieres and Timbalier Islands. The study compared storm surge elevations and

significant wave heights for historic conditions (1950), recent conditions (the 1990s),

and anticipated future conditions (2020). When comparing 1950 to 1990, the

modeling outputs revealed that the marsh shoreline directly behind the islands

experienced a 10-ft increase while the remaining portion of the study area

experienced a 6-ft increase in storm surge while. The model also revealed a 4 to 5-ft

increase in significant wave height along the marsh shoreline. This considerable

increase in storm surge and wave height was directly attributed to the 24% loss of

barrier island and marsh landmass that occurred during the period of analysis

(1950-1990). The cumulative effects of the increased wave height and storm surge

resulted in the inundation of an additional 80,000 acres of landmass within the

study area (Stone et al 2003).

Between 1990 and 2020, the model also predicted considerable increases in storm

surge elevations and significant wave heights. Storm surge increases of 10 ft to 12

ft (and greater) were found along the bay fringing the marsh north of the Isles

Dernieres. The marshes flanking Terrebonne Bay experienced surge increases of 1

to 6 ft. Significant wave height increased by up to 5 ft along the Isles Dernieres and

the marsh shoreline behind the islands while increases along Timbalier island

ranged from 6 to 8 ft. Due to the collective effects of increased wave height and

storm surge elevation, it was predicted that a Class 3 hurricane would inundate an

additional 35,000 acres of landmass in 2020 when compared to the 1990s (Stone et

al 2003).

The authors of the study concluded that the physical loss of the Isles Dernieres and

Terrebonne Islands and associated marshes has resulted and will continue to result

in increases storm surge elevations and significant wave heights (Stone et al 2003).

Although the authors of the study did not examine the incremental impacts of

individual islands on wave height and storm surge mitigation, it can reasonably be

inferred that the recommended component of construction will reduce weatherinduced erosion on the marshes north of Whiskey Island.

3.7.4 Acceptability, Completeness, Effectiveness, and Efficiency

Acceptability

The recommended component of construction is implementable from a technical,

environmental, economic, financial, political, legal, institutional, and social

perspective. Furthermore, the USACE and CPRA find the plan satisfactory.

Therefore, the recommended component of construction (with renourishment) is

acceptable to the Federal sponsor as well as the non-Federal sponsor. The

recommended component of construction was selected by and interagency and

interdisciplinary team. The Terrebonne Parish CZM also finds the recommended

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component of construction acceptable, although they indicated they would prefer

the NER Plan. Input from the public is provided in Appendix G.

Completeness

When selecting the recommended component of construction, the PDT considered a

number of factors beyond its control including real estate, operation and

maintenance, monitoring, and sponsorship factors. These factors were considered

because of their potential impacts on the realization of the recommended component

of construction.

In order to define property ownership, required estates, and potential relocations, a

Real Estate Plan (REP) was developed specifically for the recommended component

of construction (see Appendix J). An Adaptive Management Plan was developed to

describe the post-construction monitoring activities proposed for the recommended

component of construction, including costs and duration of the activities (see

Appendix I). Operation and Maintenance of the alternatives was considered during

plan formulation, particularly for the proposed hard structures (see Section 3.7.9)

and renourishment (see Section 3.7.1). Sponsorship factors, particularly related to

the non-Federal sponsor, were considered in the analysis (Appendix L). The cost

risk analysis also quantifies external risks associated with fuel prices, severe

weather downtime, pipeline length, bidders risk, steel prices, and hurricane

demobilizations. Risks and Uncertainties associated with numerical models and

relative sea-level rise are discussed in Section 3.8.

Since the above-mentioned external factors and risks were considered during the

selection of the recommended component of construction, the Federal and nonFederal sponsors agree that the plan is complete.

Effectiveness

Effectiveness is the extent to which an alternative plan alleviates the specified

problems and achieves the specified opportunities. The problems that were

identified for the Terrebonne Basin Barrier Shoreline include the following:

1. Land loss due to erosion threatens the geomorphic and hydrologic barrier

systems

2. Loss of barrier island/headland ecosystem habitat

3. Freshwater wetlands are impacted by increased salinity

4. Longshore sediments are significantly reduced, limiting the ecosystems

ability to be self-sustaining

Problem #1: Land loss will be reversed on Whiskey Island with the construction of

the recommended component of construction. Immediately after construction (TY1),

the recommended component of construction will add 469 acres of habitat (dune,

intertidal, and supratidal) to the existing island footprint, increasing the size of the

island to 1,272 acres (including dune, intertidal, and supratidal habitat). The

dimensions of the island template for Plan C will provide geomorphologic form and

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ecologic function (as defined in Section 3.3.2.2.1) plus an additional 5 years of

advanced fill. The island template is expected to provide incidental wave

dampening effects and storm surge mitigation landward of the island. The

remaining islands in the Isles Dernieres and Timbalier Island Reaches will continue

to erode at their current rate and will provide diminishing protection from waves

and storm surge. However, Raccoon Island will benefit from additional sediment

due to longshore drift.

Problem #2: Construction of the recommended component of construction (with

renourishment) will create an additional 678 AAHUs on the existing island

footprint, increasing the total ecosystem habitat benefits of the island to 857

AAHUs. For the FWOP conditions, supratidal and intertidal habitat is expected to

disappear by TY17 and TY31, respectively. There is currently no dune habitat on

the island. The recommended component of construction will create and sustain

dune habitat until TY50 and supratidal and intertidal habitat beyond the 50-year

period of analysis. Furthermore, the recommended component of construction is

expected to mitigate habitat loss of the mainland directly bay-ward of the island.

Habitat loss of the remaining islands in the Isles Dernieres and Timbalier Island

Reaches will continue at its current rate (see Table 3-19).

Problem #3: While the recommended component of construction is expected to

create some localized reductions of saltwater intrusion into the freshwater marshes

north of Whiskey Island, the benefits of this single island plan will likely be minor

when considering the system as a whole. Furthermore, the extent of these benefits

is extremely difficult to quantify. To evaluate the role of the islands and their

intervening passes in open water circulation and turbulent mixing will require

installation of long-term monitoring instruments.

Problem #4: Sediment transport along the Isles Dernieres is complex given its

fragmented nature (Georgiou et al., 2005). Within Whiskey Island, longshore

sediment transport is bi-directional. Along the east flank of the island net transport

is approximately 5,000 cy per year and directed east toward Whiskey Pass.

However, net transport along the center of the island is westward toward Caillou

Bay and Raccoon Island and increases to approximately 80,000 cy per year (Stone

and Zhang, 2001). Toward the west end of Whiskey Island the westerly net

transport decreases to approximately 50,000 cy per year. This amount of sediment

enters Caillou Bay. Longshore sediment transport on the east end of Raccoon Island

is approximately 10,000 cy per year and directed west. Depths within Caillou Bay

between Raccoon Island and Whiskey Island range from 4 ft NAVD 88 to 7 ft NAVD

88 and are less than the depth of closure of 10.5 ft NAVD 88. This indicates that

this area is within the zone of active sediment transport and up to 10,000 cy per

year may be bypassed from Whiskey Island across Caillou Bay to Raccoon Island.

Based on this analysis of existing sediment transport data, it is concluded that after

beach fill is placed on Whiskey Island during construction of the recommended

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component of construction, some of the losses associated with profile equilibration

and background erosion along Whiskey Island will be bypassed across Caillou Bay

to feed Raccoon Island. Since Raccoon Island is considered a valuable wildlife

habitat along with Whiskey Island (Isles Dernieres Barrier Islands Wildlife Refuge),

maintaining adequate areas of healthy beach, dune, and marsh is particularly

important. Restoration of Whiskey Island and subsequent longshore transport and

bypass to the west will complement the TE-29 and TE-48 projects on Raccoon Island

(NRCS, 2007), and will supplement the existing CWPPRA investments.

Opportunities for ecosystem restoration in the Terrebonne Basin Barrier Shoreline

include:

1. Increase the longevity of the barrier island geomorphic form and ecological

function

2. Improve the habitat value of the barrier island

3. Increase sediment into the longshore transport process

Opportunity #1: The recommended component of construction increases the

longevity the geomorphic form and ecologic function of Whiskey Island by restoring

the beach, dune, and marsh components of the island. The minimal dimensions of

these components were defined through analysis of historical planforms and storm

erosion modeling. Whiskey Island Plan C maintains these minimal dimensions

even after being subjected to a number of design storms (see Section 3.3.2.2.1), plus

an addition 5 years of advanced fill. Vegetative plantings, herbivory control, and

sand fencing also contribute to restoring the geomorphic form and ecologic function

of the island.

Opportunity #2: As previously stated, construction of the recommended component

of construction (with renourishment) will create an additional 678 AAHUs on the

existing island footprint, increasing the total ecosystem habitat benefits of the

island to 857 AAHUs. For the FWOP conditions, supratidal and intertidal habitat

is expected to disappear by TY17 and TY31, respectively. There is currently no

dune habitat on the island. The recommended component of construction will

create and sustain dune habitat until TY50 and supratidal and intertidal habitat

beyond the 50-year period of analysis.

Opportunity #3: The achievement of this opportunity was addressed in the

discussion of Problem #4. Based on the analysis of existing sediment transport

data, it is concluded that after beach fill is placed on Whiskey Island during

construction of the recommended component of construction, some of the losses

associated with profile equilibration and background erosion along Whiskey Island

will be bypassed across Caillou Bay to feed Raccoon Island. Restoration of Whiskey

Island and subsequent longshore transport and bypass to the west will complement

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the TE-29 and TE-48 projects on Raccoon Island (NRCS, 2007), and will supplement

the existing CWPPRA investments.

Efficiency

The recommended component of construction, which is a subset of the NER Plan,

was evaluated as a stand-alone alternative in the CE/ICA analysis. The results

from the IWR output confirmed that the recommended component of construction

was cost-effective.

3.7.5 Sustainability

The LCA TBBSR Study was identified in the LCA 2004 report as a restoration

feature that could be implemented in the near-term that addresses the most critical

needs of the Louisiana coastline. As indicated in the LCA 2004 report, the design

and operation of the LCA TBBSR Study feature would maintain the opportunity for,

and support the development of large-scale, long range comprehensive coastal

restoration. The Study is synergistic with future restoration by maintaining or

restoring the integrity of the estuaries coastline, upon which all future restoration

is dependent. The recommended component of construction will work in concert

with other LCA projects such as BUDMAT, CWPPRA, and CIAP features, in

addition to other current and future projects developed under the Louisiana Coastal

Comprehensive Plan, to improve the sustainability of the Terrebonne Basin Barrier

Shoreline.

As a result of the LCA TBBSR Study, there is a substantial improvement in terms

of resource sustainability within the Study area provided under the recommended

component of construction compared to the Future Without Project conditions.

While much of the constructed acreage created under the recommended component

of construction will decrease by the end of the period of analysis, the net effect of the

plan will be to prevent the loss of Whiskey Island. If no actions are taken, the

remaining 820 acres of the island is expected to disappear by TY31 (i.e. all dune,

supratidal, and intertidal habitat will be gone). This includes the existing critical

mangrove habitat and the back-barrier marsh created by CWPPRA project TE-50.

The majority of this loss would be prevented with implementation of the

recommended component of construction. The plan also meets the major restoration

objectives of restoring the geomorphic form and ecologic function of the barrier

islands and of restoring and improving essential habitats for fish, migratory birds,

and other terrestrial and aquatic species for the 50 year period of analysis.

The restoration of the Whiskey Island would alter the tidal prism, thereby reducing

the formation of any additional tidal passes as well as closing or narrowing existing

passes and breaches, protecting and preserving the interior marsh habitats which

would quickly erode without the protection of the sand shoreline.

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3.7.6 Components

Whiskey Plan C proposes a dune height of +6.4 ft NAVD 88 with a dune crown

width of 100 ft. The dune elevation takes into account that there will be

approximately 0.4 ft of vertical adjustments (eustatic sea level rise [ESLR],

subsidence, and compaction) occurring during the first six months after

construction. At the end of the six-month period, the dune should reach the design

elevation of +6.0 ft NAVD 88. The slopes of the beach and dune are set 60:1 and

30:1 (horizontal to vertical), respectively.

The marsh fill is proposed on the landward side of the dune at an elevation of +2.4

ft NAVD 88. Although the design elevation for the marsh is +1.6 ft NAVD 88

(Section 3.3.2.2), the marsh will be constructed at a higher elevation to account for

initial vertical adjustments. Immediately after construction (TY1), the

recommended component of construction will add 469 acres of habitat (dune,

intertidal, and supratidal) to the existing 803-acre island footprint, increasing the

size of the island to 1,272 acres. This includes 65 acres of dune, 830 acres of

supratidal, and 377 acres of intertidal habitat.

Whiskey Plan C was designed to avoid approximately 286 acres of existing

mangroves on the island to minimize the ecologic impact during construction. Plan

C was also designed to complement TE-50, which is an existing CWPPRA project

that was constructed in 2009. TE-50 created approximately 316 acres of intertidal

back-barrier marsh between the two existing mangrove stands (Figure 3-18).

The recommended component of construction will utilize beach/dune material from

the Ship Shoal borrow area and marsh material from Whiskey 3a borrow area. Fill

quantities for the dune/beach and marsh components of Whiskey Plan C are 8.3

million and 0.6 mcy, respectively. For the dune area, the material will be pumped

from the dredge to the beach. The material will then be worked on the beach by

bulldozers and front-end loaders. For the marsh area, the material will be pumped

from the offshore borrow site. Containment dikes will be constructed around the

perimeter. Sediment for the containment dikes will be dredged from existing

material inside the marsh creation area. These operations will be completed in a

manner that will minimize turbidity of the water at the dredge site and the

discharge site. Figure 3-18 shows the plan view of Whiskey Plan C.

Approximately 18,000 ft of sand fencing will be installed. The sand fences are

porous barriers that reduce wind speed along the coast such that sand being

transported by the wind accumulates on the downwind side of the fence. The sand

fences will promote deposition of windblown sand, create dune features, reduce

trampling of existing dunes by beach visitors, and protect vegetative plantings.

Vegetative plantings will include a variety of native species. The recommended

planting density is no greater than 8-ft centers.

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Figure 3-18. Whiskey Island Plan C

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The island will require two renourishment intervals in order to maintain its

geomorphologic form and ecologic function throughout the 50-year period of

analysis. The first renourishment event will occur 20 years after construction (i.e.

2032) and will include the addition of approximately 8.3 mcy of material to the dune

and supratidal beach components of the island. The second renourishment interval

will occur 40 years after construction (i.e. TY40) and will include the addition of

approximately 6.4 mcy of material to the dune and supratidal beach. No additional

marsh material will be added

3.7.7 Design, Environmental, and Construction Considerations

Project construction will require the hydraulic placement of beach and marsh fill

within the Study area. Inclement weather, especially tropical storms, may impact

the construction schedule. High seas may impact offshore dredging. Waves and

winds from storm events may also move debris, cultural resources, and pipelines on

the gulf floor. If during dredging, cultural resources are inadvertently discovered,

there could be impacts to the schedule and cost of the project. Additionally, dredge

availability may impact the schedule and cost of the project. The project could

potentially impact threatened and endangered species as well as species of special

interest. Therefore, all construction-related activities will be coordinated with the

USFWS, NMFS, and LDWF. During the PED process both the mechanics/

methodologies and phasing of fill placement will be analyzed and modified with the

goal to eliminate or minimize adverse impacts. The project team includes ecologists

and wildlife biologists who, in concert with agency scientists, will endeavor to

ensure the maintenance of habitat diversity and the stability of a diverse

assemblage of species. The primary metrics for this should be species diversity and

habitat area, to be evaluated during the monitoring and adaptive management

process.

3.7.7.1 Protection of Endangered Species and Species of Special Interest

3.7.7.1.1 West Indian Manatee

As with the NER Plan, temporary signs will be posted prior to and during all

construction/dredging activities to remind personnel to be observant for manatees

during active construction/dredging operations or within vessel movement zones

(i.e., work area), and at least one sign will be placed where it is visible to the vessel

operator. Siltation barriers, if used by the contractor, will be made of material in

which manatees could not become entangled, and will be properly secured per

technical specifications provided by the manufacture. If a manatee is sighted

within 100 yards of the active work zone, special operating conditions will be

implemented, including:

 No operation of moving equipment within 50 ft of a manatee

 All vessels will operate at no wake/idle speeds within 100 yards of the work area

 Siltation barriers, if used, will be monitored and re-secured as necessary

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Once the manatee has left the 100-yard buffer zone around the work area on its own

accord, special operating conditions are no longer necessary, but careful

observations will resume. Care will also be taken to avoid entrapment of

individuals if any structure is to be installed that could be a barrier or impediment

to manatee movement.

3.7.7.1.2 Piping Plovers

As with the NER Plan, beneficial impacts to the piping plover and its critical

habitat include the restoration of habitat and prolonged life of Whiskey Island, as

well as creating new barriers or structures that would function to protect critical

habitat. The implementation of recommended component of construction would also

increase sediment available to Raccoon Island because the long shore sediment

movement is westward.

Unavoidable short term impacts to the critical habitat would result from the

placement of sediments onto existing beach and dune habitats during construction

and renourishment. These activities would smother existing populations of benthic

prey species. However, any impacts that would occur to existing designated critical

habitat would be temporary, and would provide for the long-term maintenance

and/or enhancement of critical habitat within the Study Area. There would be no

permanent impacts to critical habitat that would change the ecological processes

that maintain it.

Construction of the recommended component of construction is likely to occur while

plovers are present. However, due to their mobility, piping plovers would be able to

avoid areas of temporary disturbance using the abundance of suitable foraging and

roosting areas adjacent to Whiskey Island. For example, Raccoon, Trinity, East, and

Timbalier Islands currently support a total of 1318 acres of critical habitat. East

Timbalier Island and Wine Island collectively provide 259 acres of suitable habitat

for piping plover, although the islands have not been technically designated as

critical habitat. These six islands are located within the immediate vicinity of

Whiskey Island.

Formal consultation on the piping plover has been conducted and the USFWS has

issued a Biological Opinion (Annex A2). The USACE has agreed to comply with the

reasonable and prudent measures (RPM) and the terms and conditions outlined in

the Biological Opinion. The following RPMs will be taken to minimize take on nonbreeding piping plovers during implementation of the recommended component of

construction:

 A baseline piping plover survey will be conducted within the migrating and

wintering season immediately prior to initial construction within the Study

Area. As part of that survey, the project footprint should be delineated using a

global position system (GPS) unit and appropriately marked/flagged for future

survey reference and data collection;

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 A survey of the intertidal benthic prey species community shall be conducted

within the migrating and wintering season immediately prior to initial

construction, at the same time as the plover distribution surveys, in order to

establish a baseline of benthic prey species diversity and abundance.

 Piping plover monitoring surveys shall be conducted during the migrating and

wintering seasons throughout initial project construction and three consecutive

years following completion of initial construction;

 To confirm re-establishment of suitable foraging habitat for migrating and

wintering plovers, monitoring surveys of the intertidal benthic prey species

community shall be conducted each year following completion of initial

construction for three consecutive years, preferably at the same time as the bird

surveys;

 The USFWS shall be notified in writing at least 3 months prior to a

renourishment event for each island. If renourishment events are conducted

during the migrating and wintering season, piping plover monitoring surveys

shall be conducted for the duration of construction activities; and

 A comprehensive report describing the actions taken to implement the RPMs

and terms and conditions associated with this incidental take statement

(including data sheets from surveys conducted) shall be submitted to the

USFWS by June 1 of the year following completion of all required surveys.

In order to be exempt from the prohibitions of Section 9 of the Endangered Species

Act, the USACE will execute the following terms and conditions.

Requirements for Piping Plover Surveys

 The USACE will conduct a minimum of two surveys per month. If conditions

require a deviation from the recommended survey schedule, such information

will be carefully documented, including an explanation why any deviation from

the recommended schedule was deemed necessary.

 Qualified professionals with shorebird/habitat survey experience will conduct

the required survey work. Piping plover monitors will be capable of detecting

and recording locations of roosting and foraging plovers, and documenting

observations in legible, complete field notes.

 Binoculars, a global positioning system (GPS) unit, a 10-60x spotting scope with

a tripod, and the USFWS-approved survey datasheet will be used during

monitoring.

 Negative (i.e., no plovers seen) and positive survey data will be recorded and

reported.

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 Piping plover locations will be recorded with a GPS unit set to record in decimal

degrees in universal transverse mercator (UTM) North American Datum 1983

(NAD83).

 Habitat, landscape, and substrate features used by piping plovers when seen

will be recorded.

 Behavior of piping plovers (e.g., foraging, roosting, preening, bathing, flying,

aggression, walking) will be documented on the USFWS-approved survey data

sheet.

 Color-bands seen on piping plovers shall also be carefully documented.

Requirements for Surveying Benthic Prey Species

 A qualified professional with sediment/macroinvertebrate sampling experience

will conduct the required benthic prey species surveys.

 A baseline macroinvertebrate survey will be conducted at the same time of the

initial piping plover survey during the migrating/wintering season immediately

prior to construction. Additional surveys will be conducted during the

migrating/wintering season each year post-construction for three consecutive

years to determine benthic prey species recovery. Such surveys will be

conducted at the same time as the plover surveys.

 Sampling will be conducted using a basic before and after control and impact

design method. Sampling will be coordinated with piping plover foraging

observations based on low tide surveys.

 In addition to recording benthic species abundance and diversity, a qualitative

measure of sediment characteristics (sand, shell, mud) will also be recorded.

 A detailed sampling methodology will be developed in coordination with the

USFWS and LDWF prior to initiating surveys.

Reporting Requirements

 All data collected during the surveys will be incorporated into an appropriate

database, preferably one for piping plovers and one for benthic prey species.

 Annual update reports will be provided to the USFWS and LDWF by June 30 of

each calendar year once construction begins. Annual update reports will include

data sheets, maps, a copy of the database, and the progress and initial findings

of piping plover and benthic community surveys, as well as any problematic

issues that may hinder future survey efforts.

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 If the USACE foresees any problematic issues that would require a change in

the recommended survey schedule due to work conditions or project delays, the

USACE will immediately notify the USFWS to resolve/correct any such issues.

 A final comprehensive report will be provided to the USFWS and LDWF by June

30 following the third year of surveys. That final report will include an analysis

of all data results from the piping plover and benthic community surveys.

 At least six months prior to mobilization, the USACE will notify the USFWS in

writing prior to each proposed renourishment event. The notification will

include whether there are any changes in the proposed amount of renourishment

per island.

Upon locating a dead or injured piping plover that may have been harmed or

destroyed as a direct or indirect result of the proposed project, the USACE will

notifying the USFWSs Lafayette, Louisiana, Field Office (337/291-3100) and the

LDWFs Natural Heritage Program (225/765-2821). Care will be taken in handling

an injured piping plover to ensure effective treatment or disposition and in handling

dead specimens to preserve biological materials in the best possible state for later

analysis.

3.7.7.1.3 Sea Turtles

Based on professional experience and related CWPPRA project construction methods, it is

anticipated that a hydraulic cutterhead dredge and booster pump(s) would be used

to excavate sediment from the available offshore borrow area(s) and directly

transport it via a submerged sediment pipeline to the islands. Environmental laws

protecting sea turtles could possibly require the cessation of work for a limited time

if the allowable number of sea turtles mortalities is exceeded during dredging.

However, turtles are typically able to avoid cutterhead dredge intakes because the

dredges move along the seabed at such a slow speed. Sediment used to construct the

containment dikes would be dredged from existing material inside the marsh

creation area rather than from offshore borrow areas. Therefore, hydraulic

cutterhead dredging operations associated with the containment dikes are not

expected to adversely impact sea turtles.

3.7.7.1.4 Brown Pelican and Colonial Nesting Birds

Whiskey Island hosts a variety of colonial nesting waterbird species, including the

brown pelican. These species breed in high densities along the shorelines and

barrier islands of Coastal Louisiana. The following section describes the measures

that will be used to avoid impacts to these species of special interest that occupy the

Study Area during portions of the year.

Due to the duration of the construction events, avoiding critical nesting periods

altogether is not feasible under the current schedule and funding constraints.

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Therefore, a combination of proactive measures, coordination, monitoring, and

avoidance will be utilized to avoid/reduce impacts to these species. Throughout

PED, consultation will continue with the LDWF, USFWS, and NMFS on detailed

contract specifications to avoid and minimize potential impacts to the brown pelican

and colonial nesting waterbirds.

Proactive measures will be taken to prevent brown pelicans and colonial nesting

waterbirds from nesting within the Study Area prior to and during construction.

These measures may include deterrents such as propane cannons, predator decoys,

or other approved bird repellant devices. These repellent devices will be placed in

designated areas within the Study Area prior to the nesting periods. Nesting

periods are April 2 through September 15 for gulls terns, and/or black skimmers;

February 16 through August 31 for nesting wading birds (i.e., herons, egrets, nightherons, ibis, and roseate spoonbills), anhingas, and/or cormorants; and April 1

through September 14 for brown pelicans. The contractor will coordinate closely

with the LDWF, USFWS, and NMFS on the timing and placement of the deterrent

devices. The USACE understands the importance of preventing nesting activities

within the Study Area that is under constructions as there is no provision for

incidental take in the Migratory Bird Treaty Act of 1918

Prior to any work, qualified personnel will conduct surveys in all potential nesting

bird habitats within the Study boundaries that may be impacted by construction or

preconstruction activities. These surveys will be conducted for both brown pelicans

and colonial nesting waterbirds. Data collection protocols will be established

through close coordination with the LDWF, USFWS, and NMFS.

 Nesting periods are April 2 through September 15 for gulls terns, and/or black

skimmers; February 16 through August 31 for nesting wading birds (i.e., herons,

egrets, night-herons, ibis, and roseate spoonbills), anhingas, and/or cormorants;

and April 1 through September 14 for brown pelicans.

 Nesting season surveys shall be conducted in all potential nesting bird habitats

within the Study boundaries that may be impacted by construction or

preconstruction activities during the nesting season. Portions of the Study area

in which there is no potential for project-related activity during the nesting

season may be excluded.

 Surveys for detecting new nesting activity will be completed on a daily basis

prior to movement of equipment, operation of vehicles, or other activities that

could potentially disrupt nesting behavior or cause harm to the birds their eggs

or young.

 Surveys should be conducted by walking the length of the Study area and

visually inspecting, using binoculars or spotting scope, for the presence of

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shorebirds exhibiting breeding behavior. If an ATV or other vehicle is needed to

cover large Study areas, the vehicle must be operated at a speed of <6 mph, shall

be run at or below the high tide line, and the Bird Monitor will stop at no greater

than 200-meter intervals to visually inspect for nesting activity.

 Daily summaries of shorebird/brown pelican abundance, location of the birds and

their activity (e.g., foraging, resting, nesting, courtship behavior), and

summaries of any nests observed including the number of eggs and fledglings,

shall be provided on the next business day on an approved report form.

The Bird Monitor shall communicate the results of their survey to the contractor

daily.

 If breeding is confirmed by the presence of a scrape, eggs, or young, the Bird

Monitor will immediately notify the appropriate personnel at the LDWF and

USFWS.

If nesting occurs during construction within the Study area, the contractor shall

establish a 650-ft buffer zone around colonies containing nesting gulls, terns, and/or

black skimmers; a 1,000-ft buffer around colonies of nesting wading birds (i.e.,

herons, egrets, night-herons, ibis, and roseate spoonbills), anhingas, and/or

cormorants; and a 2,000-ft buffer around nesting colonies of brown pelicans.

 The designated buffer zones shall be posted with clearly marked signs around

the perimeter. These markings shall be maintained until nesting is completed

or terminated. In the case of solitary nesters, nesting is not considered to be

completed until all chicks have fledged.

 No construction activities, movement of vehicles, or stockpiling of equipment

shall be allowed within the buffer area unless authorized by LDWF, USFWS,

and NMFS.

 LDWF/USFWS/NMFS-approved travel corridors shall be designated and marked

outside the buffer areas. Heavy equipment, vehicles, and pedestrians may

transit past nesting areas in these corridors. However, other activities such as

stopping or turning shall be prohibited within the designated travel corridors

adjacent to the nesting site.

 Where such a travel corridor must be established within the Study Area, it shall

avoid critical areas for shorebirds (known nesting sites, designated critical

wildlife habitat, and designated critical piping plover habitat) as much as

possible, and be marked with signs clearly delineating the travel corridor from

the shorebird buffer areas described above.

If shorebird or pelican nesting occurs within the Study Area, a bulletin board will be

placed and maintained in the construction area with the location map of the

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construction site showing the bird nesting areas and a warning, clearly visible,

stating the bird nesting areas are protected by the Federal Migratory Bird Treaty

Act.

3.7.7.1.5 Blue Crabs

The construction and renourishment of Whiskey Island Plan C will require a total of 26,012,691

cy of fill material from the Ship Shoal borrow area. Ship Shoal possesses a unique benthic

meiofaunal and macrofaunal community due to its sandy substrate and water depths. A study by

MMS found that the shoal was an important spawning, hatching, and foraging habitat for

populations of blue crab. The study also found that actively spawning, hatching, and foraging

blue crabs were present in the shoal between April and October, with the highest abundance

occurring in August (Condrey and Gelpi, 2010).

The dredging activities occurring during construction and renourishment could potentially

impact blue crab communities on Ship Shoal. Direct impacts could include physical disturbance

and temporarily loss of spawning, hatching, and foraging habitats due to alterations in water

depths, turbidity, and sediment characteristics. Indirect impacts could include the alteration of

food web dynamics through the smothering and removal of benthic prey species (Stone et al.,

2009).

In order to minimize impacts to the blue crab communities during construction and

renourishment, the USACE will take the following precautions:

• Survey blue crab populations within the Ship Shoal disturbance area prior to, during, and

after construction of the NER Plan;

• Minimize dredging activities during the spawning, hatching, and foraging season (April

through October);

• Minimize the depth of dredging to prevent the formation of hypoxic zones; and

• Phase the dredging activities such that blue crabs will have sufficient habitat adjacent to

the disturbance area for relocation.

All dredging activities will be conducted in close coordination with NMFS, USWFS, and

LDWL.

3.7.7.2 Beach and Dune Construction

As previously stated it is anticipated that a hydraulic cutterhead dredge would be

used to excavate sand from the available sand borrow areas. The sand will then be

pumped through a series of booster pumps to the beach/dune fill template via a

submerged sediment pipeline.

During construction the contractor would be directed to maintain dedicated

equipment loading/unloading areas, staging areas, and access corridors to minimize

the impacts to the island. Existing mangrove habitats and prior restoration project

areas shall be avoided by construction equipment and construction-related

activities.

Once on the beach, the sediment pipeline will run parallel to the shoreline. Frontend loaders that are equipped with grapple arms would be utilized in the placement

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and relocation of the sediment pipeline. For segments of the fill template that have

sufficient width, a Y-valve would be utilized to enable placement of multiple

sediment pipelines along the template. The bifurcation of the discharge pipeline

would facilitate lower discharge velocities and increased sediment retention within

the fill template. In order to minimize the impact on piping plover, the beach would

be constructed in sections to allow the birds to move to areas that are not currently

under construction.

The dredge material would be worked on the beach by bulldozers to meet the

specified template grades, slopes and widths. Construction methods may vary but it

is anticipated that sand placement along the shoreline would be controlled by

advancing a temporary sand dike several hundred ft parallel to shore ahead of the

discharge terminus. This aids in reducing initial fill losses offshore and helps

control temporary turbidity that may result from the fill placement operations.

Typically water drainage and discharges would be directed offshore into the Gulf of

Mexico or into existing marsh areas to nourish these habitats.

If construction is completed during the summer, fall, or winter months, the dune

and supratidal areas would be temporarily stabilized through aerial dispersion of

grass seed. During the first spring following construction, the dune and supratidal

areas would be planted with a more permanent combination of plants including

bitter panicum (Panicum amarum var amarum Fourchon), sea oats (Uniola

paniculata Caminada), marshhay cordgrass (Spartina patens Gulf Coast) and gulf

cordgrass (Spartina spartinae). Vegetation would be manually planted on 8-ft

centers and would provide 100% coverage of the dune and supratidal areas.

An additional 15% of the dune and supratidal swale areas will be planted with

woody species in TY2. The vegetation will be manually planted on 8-ft centers.

Woody species will include matrimony vine (Lycium barbarum), wax myrtle (Myrica

cerifera), iva (Iva imbricata), eastern baccharis (Baccharis halimifolia), and hercules

club (Zanthoxylum clava-herculis).

3.7.7.3 Back-Barrier Marsh Construction

As with the beach fill, it is anticipated that a hydraulic cutterhead dredge and

booster pump(s) would be used to excavate sediment from the available offshore

marsh borrow area(s) and directly transport it via a submerged sediment pipeline to

the marsh platform. Sediment used to construct the marsh containment dikes will

be dredged from existing material inside the marsh creation area rather than from

offshore borrow areas.

Construction operations would be done in a manner that would minimize turbidity.

Discharge and dewatering from the marsh fill shall typically be directed towards

the Gulf of Mexico including orienting discharge pipes such that the hydraulic flow

moves in a gulfward direction and locating dewatering structures on the gulf side of

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the Study area. The contractor may employ other methods such as building interior

containment dikes and creating a drainage gradient towards the gulf. If excess

turbidity occurs, the contractor will be directed to change the operating procedure to

reduce the degree of turbidity.

Herbaceous planting of the marsh template will be conducted in two phases. The

first phase will occur in the second year following construction (i.e. TY3) and will

consist of covering 50% of the platform. The remaining 50% of the platform will be

planted the following year. The species used for planting will primarily consist of

smooth cordgrass (Spartina alterniflora Vermilion). The vegetation will be

manually planted on 8-ft centers.

3.7.7.4 Construction Access Considerations

The required land based equipment including but not limited to graders, loaders,

dozers, and marsh buggy backhoes will be transported from the mainland to the

islands via barge(s). The contractor will excavate access channels from either the

Gulf of Mexico or the back bays to the islands utilizing barge mounted clamshell

dredges with temporary sidecast disposal. Exact access to the beach/dune and

marsh fill templates will be determined and coordinated during the PED phase and

will include the necessary easements. The contractor will be required to submit a

construction access plan which shall contain provisions for the restoration of any

damaged habitats.

Miscellaneous equipment to be stored on the beach may include sediment pipeline,

graders, loaders, dozers, marsh buggy backhoes, weirs, grade stakes, light towers,

fuel tanks with containment, welding machine, and temporary shanty for personnel.

Further, the contractor will locate a quarters barge in an appropriate sheltered

staging area to house the land based personnel and office facilities.

3.7.8 Real Estate Requirements

The following sections highlight the real estate considerations for the recommended

component of construction plan. Additional information is provided in the Real

Estate Plan (Appendix J).

3.7.8.1 Land Acquisition

Whiskey Island is an uninhabited island off the coast of Terrebonne Parish. Access

to the Island is only by boat. The island has a narrow beach area on the Gulf front

and broken marsh on the landside. Fill for the dune/beach and marsh components

will be placed directly into water bottoms owned by the State of Louisiana as well as

the upland areas owned by the State. The island is owned by the State of Louisiana

and is under the jurisdiction of the Louisiana Department of Wildlife & Fisheries

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for Isles Dernieres Barrier Island Refuge; therefore, easements are not needed for

this island, only a Grant of Particular Use.

3.7.8.2 Estates

The LDWF owns fee (excluding minerals), therefore the State has sufficient

interests to meet the requirements of the Study. A Grant of Particular Use (GPU)

would be given from the State to USACE. The rights delineated in the GPU will be

similar to the language in the following standard estates: Perpetual Beach

Nourishment Easement, Perpetual Restrictive Dune Easement, & Temporary Work

Area Easement. The acquisition of these specific estates is not required because the

land is owned by the Non Federal Sponsor. Therefore, only administrative costs

would apply.

Two borrow areas are identified for use. Both are located in the Gulf of Mexico, one

identified as Whiskey 3A (48 acres) and is located in within the State waters

bottoms of the Gulf of Mexico and the other, Ship Shoal site (560 acres) is located

under Federal jurisdiction within the Gulf of Mexico. Therefore, no borrow

easement is necessary; the State of Louisiana will issue a Grant of Particular Use

(GPU) or a Letter Agreement , such as the sample one shown in Exhibit IV, between

governmental agencies to cover project features for the construction of this Study.

Appropriate permitting will be obtained from the Mineral Management Service

(MMS) prior to dredging operations.

3.7.8.3 Acquisition Costs

The proposed construction and renourishment of the tentatively selected plan will

occur entirely on State owned properties; therefore, only minimal administrative

costs will be incurred associated with obtaining title, mapping and right of entry for

construction from the State. Costs are estimated to be approximately $8,000.

The highest and best use of the property is the same before the project is

constructed as after the project is constructed. The project has very nominal impact

on the value of the property. Because the real estate interests provided by the State

are minor, it is not anticipated at this time, that the non-Federal sponsor will seek

credit for providing the land, easements, rights-of-way, relocation, and disposal

areas (LERRD). This will be outlined in the Project Partnering Agreement.

3.7.8.4 Relocation Assistance

The Study does not displace residential, commercial or industrial facilities.

Therefore, the provisions of Title II of Public Law 91-646, as amended are not

applicable.

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3.7.8.5 Mineral Exploration

Although LL&E, has the right to access the surface of Whiskey Island to explore for

minerals, it is not likely that they will do so. Whiskey Island is part of the

Terrebonne Barrier Island Refuge and to conduct mineral explorations on the island

would be inconsistent with the protection of wildlife. LL&E is a large landowner

with property throughout south Louisiana. It is important for this company to

maintain an image that portrays it as an environmental steward. In addition, the

LDWF has established procedures for granting permits for exploratory activities on

its wetland management areas (WMAs).

3.7.9 Operations and Maintenance Considerations

3.7.9.1 Breakwaters and Terminal Groin

The purpose of Operation and Maintenance (O&M) is to allow a project to continue

to function. For a structure such as a breakwater or a terminal groin, O&M is

required to keep the structure functioning at a certain level to provide the benefits

claimed in the analysis.

There are no hard structures proposed as part of Whiskey Island Plan C. However,

Whiskey Plan C will require two renourishment intervals. The first will occur at

TY20 and will include the addition of the same amount of dune and supratidal

beach habitat that was originally created in TY1 (i.e. add a Plan C to the template

at TY20). The second renourishment interval will occur at TY40 and will include

the addition of the same amount of dune and supratidal beach habitat needed to

construct a Plan B template. Renourishment is discussed in further detail in

Section 3.7.1.

3.7.10 Monitoring Plan and Adaptive Management

The details for post-construction monitoring and adaptive management activities

proposed for the Study along with estimates of cost and duration are presented in

Appendix I.

3.7.11 Effectiveness of the Recommended Component of

Construction in Meeting Goals and Objectives

The barrier island restoration components of the recommended component of

construction would achieve the planning objectives by maximizing the barrier

islands ability to provide geomorphic and hydrologic form and ecological function

over the 50 year period of analysis as well as improve critical barrier island habitats

for fish, migratory birds, and other terrestrial and aquatic species. Sediment would

be entered into the system to supplement longshore sediment transport processes

along the gulf shoreline by mechanically introducing compatible sediment, and

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increasing the ability of the restored area to continue to function and provide

habitat with minimum continuing intervention.

The recommended component of construction is the plan within the 2007 WRDA

authorization that best meets the goal of the 2004 LCA Plan to address critical

near-term needs for shoreline restoration for Terrebonne Basin through simulating

historical conditions by enlarging the barrier islands (width and dune crest) and

reducing the current number of breaches to ensure the continuing geomorphic and

hydrologic form and function of the barrier islands. The selection of the

recommended component of construction was based on a thorough review of existing

scientific and engineering reports, as well as geospatial, survey, and geotechnical

data which reaffirmed that the findings of the Final Programmatic Environmental

Impact Statement remain valid.

3.7.12 Effectiveness of Recommended Component of Construction

in Meeting Environmental Operating Principles

The recommended component of construction is also the plan within the 2007

WRDA authorization that best meets the USACE Principles and Guidelines of

completeness, effectiveness, efficiency, and acceptability, as well as the

Environmental Operating Principles of environmental sustainability,

interdependence, balance and synergy, accountability, knowledge, respect, and

assessing and mitigating cumulative impacts.

3.7.13 Compensatory Mitigation Measures

No compensatory mitigation is required for this Study. As an ecosystem restoration

project, the alternatives were designed to avoid environmental impacts. Any

incidental temporary impacts that might be incurred during construction will be

more than offset by the net habitat value created by the recommended component of

construction.

3.8 FINAL ARRAY IMPACTS

The renourishment cycles that were developed for the NER Plan and the

recommended component of construction were applied to the other alternatives in

the final array in order to quantify direct and indirect impacts. Island and borrow

area impacts caused by the initial construction and renourishment of the Final

Array are summarized in Table 3-39. Temporal distributions of habitat acreages

and the resulting AAHUs for each alternative are provided in Tables 3-40 through

3-44.

Table 3-45 presents a comparison of the impacts of each of the alternatives in the

Final Array on the significant resources within the Study Area. These significant

resources are defined in Section 4 and further analyzed in Section 5.

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Table 3-39: Island and Borrow Area Impacts of the Final Array

Alternative Island Plan

Area

Restore

d at

TY1

Area

Create

d at

TY1

Total

Area

Impacte

d at TY1

Net

Area

at

TY50

Net

AAHUs

Total Fill

Volumea

Total Cut

Volumea

Borrow

Area

Footprint a

Excavate

d Access

Channel

Footprint b

Northern

Containme

nt Dike

Footprintc

(acres) (acres) (acres) (acres) (cy) (cy) (acres) (acres) (acres)

Alternative 5(NER Plan)

Raccoon w/ TG Plan E 235 554 789 641 477 11,937,877 13,803,647 675 29 66Whiskey Plan C 803 469 1,272 527 678 23,599,804 26,940,249 1,394 13 23Trinity Plan C 564 585 1,149 289 628 11,400,695 14,656,060 758 59 117Timbalier Plan E 955 1,675 2,630 1324 1100 20,246,338 24,027,311 894 81 162

Total 2,557 3,283 5,840 2781 2883 67,184,714 79,427,267 3,721 182 368

Alternative 11 Whiskey Plan C 803 469 1,272 527 678 23,599,804 26,940,249 1,394 13 23Alternative 2 Timbalier Plan E 955 1,675 2,630 1324 1100 20,246,338 25,746,132 1,035 81 162Alternative 3

Whiskey Plan C 803 469 1,272 527 678 23,599,804 26,766,332 1,385 13 23Timbalier Plan E 955 1,675 2,630 1324 1100 20,246,338 25,746,132 1,035 81 162

Total 1,758 2,144 3,902 1851 1778 43,846,142 52,512,464 2,420 94 185

Alternative 4

Whiskey Plan C 803 469 1,272 527 678 23,599,804 26,766,332 1,385 13 23Trinity Plan C 564 585 1,149 289 628 11,400,695 13,472,599 686 59 117Timbalier Plan E 955 1,675 2,630 1324 1100 20,246,338 25,746,132 1,035 81 162

Total 2,322 2,729 5,051 2140 2406 55,246,837 65,985,063 3,106 153 302

a Includes renourishmentb All material dredged from the access channel will be used to create the northern containment dike.c The northern containment dike separates the marsh fill from the bay. This footprint is accounted for in the overall island footprint

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Table 3-40: Habitat Acres for Alternative 5 (NER Plan)

Habitat

Type

Habitat Acres

AAHUs TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

FWOP

Dune 95 85 39 12 0 0 0 0 0 0 0 0 0

675 Supratidal 1209 1152 1018 419 141 131 89 79 37 34 1 1 0

Intertidal 1315 1319 1227 1389 961 927 791 757 622 572 122 112 21

Total 2619 2557 2284 1820 1102 1058 881 836 659 605 123 113 21

FWP

Dune 95 472 416 313 20 83 71 198 179 364 62 113 3

3558 Supratidal 1209 4320 3579 3282 2920 3129 2193 2385 1354 1391 1003 1264 660

Intertidal 1315 1048 1550 1577 1556 1694 2244 2373 2892 2849 2461 2427 2118

Total 2619 5840 5545 5172 4496 4905 4508 4956 4425 4604 3526 3803 2781

Neta

Dune 0 387 377 301 20 83 71 198 179 364 62 113 3

2883 Supratidal 0 3168 2561 2863 2779 2998 2104 2306 1317 1357 1002 1263 660

Intertidal 0 -271 323 189 595 766 1452 1616 2271 2277 2339 2315 2097

Total 0 3283 3261 3352 3394 3847 3628 4120 3766 3999 3402 3690 2760

a Net habitat acres = FWP habitat acres  FWOP habitat acres

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Table 3-41: Habitat Acres for Alternative 11

Habitat

Type

Habitat Acres

AAHUs TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

FWOP

Dune 0 0 0 0 0 0 0 0 0 0 0 0 0

179 Supratidal 377 367 389 5 0 0 0 0 0 0 0 0 0

Intertidal 443 436 345 640 476 466 426 416 375 338 0 0 0

Total 820 803 734 645 476 466 426 416 375 338 0 0 0

FWP

Dune 0 65 61 57 0 65 61 61 57 51 0 57 0

857 Supratidal 377 830 328 223 84 496 375 344 223 209 84 387 164

Intertidal 443 377 808 828 847 834 782 769 717 693 472 461 363

Total 820 1272 1197 1108 931 1395 1218 1174 997 953 556 905 527

Neta

Dune 0 65 61 57 0 65 61 61 57 51 0 57 0

678 Supratidal 0 464 -61 218 84 496 375 344 223 209 84 387 164

Intertidal 0 -59 463 188 371 368 356 353 342 355 472 461 363

Total 0 469 463 463 455 929 792 758 622 615 556 905 527

a Net habitat acres = FWP habitat acres  FWOP habitat acres

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Table 3-42: Habitat Acres for Alternative 2

Habitat

Type

Habitat Acres

AAHUs TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

FWOP

Dune 57 53 33 9 0 0 0 0 0 0 0 0 0

336 Supratidal 549 529 457 339 132 122 84 74 36 32 1 1 0

Intertidal 374 373 397 364 278 266 218 206 158 149 71 65 13

Total 979 955 887 712 409 388 301 280 194 181 73 67 13

FWP

Dune 57 215 183 160 0 0 0 0 0 155 13 12 0

1436 Supratidal 549 2346 2257 2130 1996 1859 1313 1176 629 667 524 495 236

Intertidal 374 69 71 74 76 183 612 719 1148 1146 1123 1120 1088

Total 979 2630 2511 2364 2072 2043 1925 1895 1777 1968 1660 1626 1324

Neta

Dune 0 162 151 151 0 0 0 0 0 155 13 12 0

1100 Supratidal 0 1817 1800 1791 1864 1737 1229 1102 593 635 523 494 236

Intertidal 0 -304 -326 -290 -202 -83 394 513 990 996 1052 1054 1075

Total 0 1675 1624 1652 1663 1655 1623 1615 1584 1786 1588 1560 1311

a Net habitat acres = FWP habitat acres  FWOP habitat acres

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Table 3-43: Habitat Acres for Alternative 3

Habitat

Type

Habitat Acres

AAHUs TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

FWOP

Dune 57 53 33 9 0 0 0 0 0 0 0 0 0

515 Supratidal 926 896 846 344 132 122 84 74 36 32 1 1 0

Intertidal 817 809 742 1004 754 732 644 622 533 487 71 65 13

Total 1799 1758 1621 1357 885 854 727 696 569 519 73 67 13

FWP

Dune 57 280 244 217 0 65 61 61 57 206 13 69 0

2293 Supratidal 926 3176 2585 2353 2080 2355 1688 1520 852 876 608 882 400

Intertidal 817 446 879 902 923 1017 1394 1488 1865 1839 1595 1581 1451

Total 1799 3902 3708 3472 3003 3438 3143 3069 2774 2921 2216 2531 1851

Neta

Dune 0 227 212 208 0 65 61 61 57 206 13 69 0

1778 Supratidal 0 2281 1739 2009 1948 2233 1604 1446 816 844 607 881 400

Intertidal 0 -363 137 -102 169 285 750 866 1332 1351 1524 1515 1438

Total 0 2144 2087 2115 2118 2584 2415 2373 2206 2401 2144 2465 1838

a Net habitat acres = FWP habitat acres  FWOP habitat acres

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Table 3-44: Habitat Acres for Alternative 4

Habitat

Type

Habitat Acres

AAHUs TY0 TY1 TY5 TY10 TY20 TY21 TY25 TY26 TY30 TY31 TY40 TY41 TY50

FWOP

Dune 96 85 40 12 0 0 0 0 0 0 0 0 0

631 Supratidal 1158 1102 988 405 135 125 86 76 38 33 1 1 0

Intertidal 1128 1135 1063 1247 868 837 715 684 560 513 84 77 21

Total 2381 2322 2091 1663 1002 962 800 760 598 546 86 79 21

FWP

Dune 96 409 366 284 0 65 61 190 179 319 47 99 0

3037 Supratidal 1158 3632 2901 2623 2270 2525 1778 2016 1172 1187 838 1098 490

Intertidal 1128 1010 1511 1537 1517 1612 1991 2078 2426 2382 1975 1943 1650

Total 2381 5051 4778 4444 3787 4203 3830 4284 3777 3888 2860 3139 2140

Neta

Dune 0 324 328 272 0 65 61 190 179 319 47 99 0

2406 Supratidal 0 2531 1913 2219 2135 2400 1692 1940 1134 1154 837 1097 490

Intertidal 0 -125 448 290 649 774 1276 1394 1866 1868 1892 1865 1629

Total 0 2729 2687 2781 2785 3240 3029 3524 3180 3341 2775 3061 2119

a Net habitat acres = FWP habitat acres  FWOP habitat acres

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Table 3-45: Comparison of Costs, Benefits, Impacts, and Effectiveness of Each Alternative in the FinalArray

No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

A. CostsPreliminary Costs $0 $408,000,000 $79,600,000 $170,000,000 $247,000,000 $329,000,000Annualized Preliminary Costs $0 $20,830,000 $4,070,000 $8,710,000 $12,640,000 $16,820,000Fully-funded Project Costswithout Renourishmenta $0 $689,000,000 $119,000,000 NA NA NAFully-funded Project Costs withRenourishmenta $0 $1,246,000,000 $461,000,000 NA NA NACost Effective/ Best Buy Best Buy Best Buy Cost Effective Best Buy Best Buy Best BuyB. BenefitsNet AAHUs withoutRenourishment 0 2063 379 871 1250 1637Net AAHUs withRenourishment 0 2883 678 1100 1778 2406C. Impacts to Significant ResourcesSoil

Loss of 3,220 acres ofexisting barrier soilresources from the sevenislands (Raccoon, Whiskey,Trinity, East, Wine,Timbalier, East TimbalierIsland) over 50-year periodof analysis.

Restore net total of2781 acres of soils over50-year period ofanalysis

Restore net total of527 acres of soils over50-year period ofanalysis

Restore net total of1,324 acres of soilsover 50-year period ofanalysis

Restore net total of1,851 acres of soilsover 50-year period ofanalysis

Restore net total of2140 acres of soilsover 50-year period ofanalysis

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Water bottoms

Conversion ofapproximately 3,220 acres ofexisting Terrebonne Basinbarrier island beach, duneand marsh habitats to waterbottoms.

Initial constructionwould remove a total of55,787,481 cy of borrowmaterial from a total of2498 acres of waterbottoms in the offshoreborrow areas.Renourishment wouldremove a total of23,639,786 cy from atotal of 1,222 acres ofwater bottoms inoffshore borrow areas.Initial constructionwould cover a total of3,283 acres of waterbottoms and existingfragmented barrierhabitats.Renourishment woulddirectly cover 71 acreson Raccoon, 474 acresat TY 20 and 349 acresat TY40 on WhiskeyIsland; 537 acres onTrinity Island at TY 25;and 202 acres onTimbalier Island atTY30.

Initial constructionwould remove a totalof 10,340,701 cy ofsediments from a totalof 535 acres of borrowsite water.Renourishment wouldremove a total of16,599,548 cy ofborrow material froma total of 859 acres ofwater bottoms.Initial constructionwould coverapproximately 469acres of waterbottoms andfragmented barrierhabitats.Renourishment withborrow material fromShip Shoal  7 woulddirectly impact a totalof 474 acres and 349acres of waterbottoms andfragmented barrierhabitats at TY20 andTY40, respectively

Initial constructionwould remove a totalof 25,214,803 cy ofsediments from a totalof 1,375 acres ofborrow site waterbottoms including.Renourshiment atTY30 would remove atotal of 531,329 cy ofborrow material froma total of 26 acres ofwater bottoms.Initial constructionwould coverapproximately 1,675acres of existing waterbottoms andfragmented barrierhabitats.Renourishment atTY30, with borrowmaterial from SouthPelto  6, woulddirectly impact a totalof 202 acres of waterbottoms andfragmented barrierhabitats

Initial constructionwould remove a totalof 35,381,587 cy ofborrow material froma total of 1,535 acresof water bottoms inthe offshore borrowareas. Renourishmentwould remove a totalof 17,130,877 cy froma total of 885 acres ofwater bottoms inoffshore borrow areas.Initial constructionwould cover a total of2,144 acres of waterbottoms and existingfragmented barrierhabitats.Renourishment woulddirectly cover 474acres at TY 20 and349 acres at TY30 onWhiskey Island and202 acres onTimbalier Island atTY40

Initial constructionwould remove a totalof 44,544,496 cy ofborrow material froma total of 1,998 acresof water bottoms inthe offshore borrowareas. Renourishmentwould remove a totalof 21,440,567 cy froma total of 1,108 acresof water bottoms inoffshore borrow areas.Initial constructionwould cover a total of2,729 acres of waterbottoms and existingfragmented barrierhabitats.Renourishment woulddirectly cover 474acres at TY 20 and349 acres at TY40 onWhiskey Island; 537acres on TrinityIsland at TY 25; and202 acres onTimbalier Island atTY30.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Flow and Water Levels

As barrier land loss andchannelization continues,hydrologic connectionsbetween the gulf andinterior areas increase andexacerbate interior land lossand conversion of habitattypes. Continued loss ofbarrier systems result inreduction and eventual lossof the natural protectivestorm buffering of thesebarrier systems

The restoration of atotal of 5,840 acres onRaccoon, Timbalier,Trinity, and WhiskeyIslands would restorethese barrier islands totheir minimalgeormorphological formthereby enabling thesebarrier islands toabsorb wave energyduring storms and fairweather conditions andprovide some stormsurge protection for theinterior marshes withinthe basin, which woulddecrease land losserosion rates.

The direct impacts tocoastal processes,flows and water levelsof implementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), but to a muchlesser degree.Alternative 11 wouldrestore thegeomorphologic formand ecologicalfunction to WhiskeyIsland resulting in aninitial island of 1,272acres.

The direct impacts tocoastal processes,flows and water levelsof implementingAlternative 2 wouldbe similar to thosedescribed for theTimbalier Islandcomponent ofAlternative 5 (NERPlan), but to a muchlesser degree.Alternative 2 wouldrestore thegeomorphologic formand ecologicalfunction to TimbalierIsland resulting in aninitial island of 2,630acres

The direct impacts tocoastal processes,flows and water levelsof implementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NERPlan), but to a muchlesser degree.Alternative 3 wouldinitially restore thegeomorphologic formand ecologicalfunction to a 1,272-acre Whiskey Islandand 2,630-acreTimbalier Island.

The direct impacts tocoastal processes,flows and water levelsof implementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponents ofAlternative 5 (NERPlan), but to a lesserdegree. Alternative 4would initially restorethe geomorphologicform and ecologicalfunction to a 1,272-acre Whiskey Island,1,149-acre TrinityIsland and 2,630-acreTimbalier Island.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Sediment and Erosion

Since there is little-to-nosediment supply, for the NoAction Alternative,approximately 3,220 acres ofexisting barrier sedimentresources from the sevenisland Terrebonne Basinbarrier system (EastTimbalier, Timbalier,Trinity, East Island, Wine,Whiskey and RaccoonIsland) would likelycontinue to erode similar tohistoric erosion rates andeventually convert intoshallow open water bottoms.Sediments eroded fromthese barrier islands wouldbe lost offshore.

A portion of the total67,184,714 cy of borrowsediments placed forrestoration of the fourbarrier islands wouldbe redistributed, vianatural coastallongshore transportprocess, throughout theTerrebonne barrierisland system over the50-year period ofanalysis.The proposed terminalgroin, as well as theexisting segmentedbreakwaters, onRaccoon Island wouldfunction to interceptthe net longshoresediment flux, therebyretaining sediments onthe beach up-drift ofthe groin and withinthe tombolos shorewardof the breakwaters.Sedimentation ratesalong Whiskey, Trinityand Timbalier Islandswould likely remainunchanged.

The impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NER)but to a lesser degree,including the naturalredistribution of aportion of the total23,599,804 cy ofsediments throughoutthe Terrebonne Basinbarrier island systemover the 50-yearperiod of analysis.

The impacts ofimplementingAlternative 2 wouldbe similar to thosedescribed for theTimbalier Islandcomponent ofAlternative 5 (NER)but to a lesser degree,including the naturalredistribution of aportion of the total20,246,338 cy ofsediments throughoutthe Terrebonne Basinbarrier island systemover the 50-yearperiod of analysis.

The impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NER)but to a lesser degree,including the naturalredistribution of aportion of the total43,846,142 cy ofsediments throughoutthe Terrebonne Basinbarrier island systemover the 50-yearperiod of analysis.

The impacts ofimplementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity, andTimbalier Islandscomponents ofAlternative 5 (NER)but to a lesser degree,including the naturalredistribution of aportion of the total55,246,837 cy ofsediments throughoutthe Terrebonne Basinbarrier island systemover the 50-yearperiod of analysis.

Water Use and Supply

There are no water supplyfacilities within the StudyArea.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Groundwater

The No Action Alternativewould not cause orcontribute to any impacts togroundwater.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

Impacts similar to theNo Action Alternative.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Water Quality

Without action, theTerrebonne Basin wouldstill be affected by naturaland anthropogenic activitieshaving both beneficial anddetrimental effects to waterquality. Some of theseactivities include: otherrestoration efforts, waterquality managementprograms, programsaddressing hypoxia in thenorthern Gulf of Mexico, thecontinuation of erosion andsubsidence of coastalLouisiana; oil and gasdevelopment, and flooddamage reduction andnavigation projects.

The direct impacts ofimplementingAlternative 5 (NERPlan) would primarilyresult from thedischarge of 67,184,714cy of dredged materialand associated effluentwaters duringconstruction. Proposedrestoration featureswould not result ineither long-term orshort-term waterquality impacts to theadjacent aquaticecosystem. Potentialimpacts of dredgedmaterial effluentdischarges wouldinclude increasedturbidity and decreasedoxygen concentrations,are expected to beshort-lived and wouldlikely result intemporary and minorimpacts to waterquality, if any.

The direct impactswater quality ofimplementingAlternative 11 wouldbe similar, but to amuch lesser degree, tothose described forthe Whiskey Islandcomponent ofAlternative 5 (NERPlan). The dischargeof 23,599,804 cy ofdredged material andassociated effluentwaters duringconstruction wouldinclude increasedturbidity anddecreased oxygenconcentrations, whichare expected to beshort-lived and wouldlikely result intemporary and minorimpacts to waterquality, if any.

The direct impactswater quality ofimplementingAlternative 2 wouldbe similar, but to amuch lesser degree, tothose described forthe Timbalier Islandcomponent ofAlternative 5 (NERPlan). The dischargeof 20,246,338 cy ofdredged material andassociated effluentwaters duringconstruction wouldinclude increasedturbidity anddecreased oxygenconcentrations, whichare expected to beshort-lived and wouldlikely result intemporary and minorimpacts to waterquality, if any.

The direct impactswater quality ofimplementingAlternative 3 wouldbe similar, but to amuch lesser degree, tothose described forthe Whiskey andTimbalier Islandscomponents ofAlternative 5 (NERPlan). The dischargeof 43,846,142 cy ofdredged material andassociated effluentwaters duringconstruction wouldinclude increasedturbidity anddecreased oxygenconcentrations, whichare expected to beshort-lived and wouldlikely result intemporary and minorimpacts to waterquality, if any.

The direct impactswater quality ofimplementingAlternative 4 wouldbe similar, but to alesser degree, to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponents ofAlternative 5 (NERPlan). The dischargeof 55,246,837 cy ofdredged material andassociated effluentwaters duringconstruction wouldinclude increasedturbidity anddecreased oxygenconcentrations, whichare expected to beshort-lived and wouldlikely result intemporary and minorimpacts to waterquality, if any.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Salinity

Continued barrier andinterior land losses resultsin conversion to open waterhabitats; increased numberof tidal inlets, disruption ofthe tidal prism andincreased salinity intrusioninto Terrebonne Basin. Theestuarine system would beconverted to a more marinesystem thereby significantlyreducing productivity.Vegetation species would bedominated by more salttolerant species and existingsalt-intolerant specieswould be displaced tofresher inland areas

The impacts ofimplementingAlternative 5 (NERPlan) would restore anet total of 2,781 acreson Raccoon, Whiskey,Trinity and TimbalierIslands restoring thesebarrier islands to theirminimalgeormorphological formand ecologicalfunctions.ImplementingAlternative 5 (NERPlan) would maintainthe importantgeomorphic boundarybetween the highersalinity waters fromthe GOM and the lesssaline Terrebonneestuarine systemthereby preventing theconversion of thebarrier system and theinterior estuarinesystems to open marinehabitats and contributeto maintaining theestuarine salinitygradients.

The impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), includingrestoring a net total of527 acres of WhiskeyIsland to its minimalgeormorphologicalform and ecologicalfunctions over the 50-year period ofanalysis therebypreventing theconversion of aportion of theTerrebonne barriersystem and theinterior estuarinesystems to openmarine habitats aswell as contributing tomaintaining theestuarine salinitygradients.

The impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NERPlan), includingrestoring a net total of1,324 acres ofWhiskey andTimbalier Islands totheir minimalgeormorphologicalforms and ecologicalfunctions over the 50-year period ofanalysis therebypreventing theconversion of aportion of theTerrebonne barriersystem and theinterior estuarinesystems to openmarine habitats aswell as contributing tomaintaining theestuarine salinitygradients.

The impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NERPlan), includingrestoring a net total of1,851 acres ofWhiskey andTimbalier Islands totheir minimalgeormorphologicalforms and ecologicalfunctions over the 50-year period ofanalysis therebypreventing theconversion of aportion of theTerrebonne barriersystem and theinterior estuarinesystems to openmarine habitats aswell as contributing tomaintaining theestuarine salinitygradients.

The indirect impactsof implementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NERPlan), includingrestoring a net total of

2,140 acres of

Whiskey, Trinity and

Timbalier Islands totheir minimalgeormorphologicalforms and ecologicalfunctions over the 50-year period ofanalysis therebypreventing theconversion of aportion of theTerrebonne barriersystem and theinterior estuarinesystems to openmarine habitats aswell as contributing tomaintaining theestuarine salinitygradients.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Air Quality

Without any action, airquality throughout thecoastal Louisiana area,including the Study Area,would likely continue todecline due to continuedhuman population growththroughout the generalcoastal area, furthercommercialization andindustrialization (e.g., oiland gas operations),increased numbers of motorvehicles, and increasedemissions from variousengines.

Over the 50-year periodof analysis Alternative5 (NER) would restorea net total of 1,459acres of vegetatedbarrier habitats thatwould help to improvelocal air quality byreducing particulatesand gaseous airpollutants. Directimpacts to ambient airquality, resultingprimarily fromimplementingAlternative 5 (NERPlan) would beprimarily related toemissions ofconstruction equipmentwithin the Study Area.Impacts would betemporary andlocalized, with airquality returning topre-constructionconditions shortly aftercompletion ofconstruction activities.

The impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NER)with restoration of anet total of 311 acresof vegetated barrierhabitats that wouldhelp to improve localair quality byreducing particulatesand gaseous airpollutants

The impacts ofimplementingAlternative 2 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NER)with restoration of anet total of 706 acresof vegetated barrierhabitats that wouldhelp to improve localair quality byreducing particulatesand gaseous airpollutants.

The impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NER)with restoration of anet total of 1,017acres of vegetatedbarrier habitats thatwould help to improvelocal air quality byreducing particulatesand gaseous airpollutants

The impacts ofimplementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponents ofAlternative 5 (NER)with restoration of anet total of 1,120acres of vegetatedbarrier habitats thatwould help to improvelocal air quality byreducing particulatesand gaseous airpollutants.

Noise

The No Action Alternativewould have no direct impacton noise. Existingconditions would persist.Localized and temporarynoise impacts, such ascommercial and recreationalfishing boats and oil and gasexploration activities, wouldlikely continue to affect fish,wildlife and those humansthat utilize the Study Area.

Construction activitiesassociated withimplementingAlternative 5 (NERPlan) would result intemporary andlocalized increases tonoise levels in theStudy Area. Any noisewould be within OSHAstandards.

Constructionactivities associatedwith implementingAlternative 11 wouldresult in temporaryand localizedincreases to noiselevels in the StudyArea. Any noisewould be withinOSHA standards.

Constructionactivities associatedwith implementingAlternative 2 wouldresult in temporaryand localizedincreases to noiselevels in the StudyArea. Any noisewould be withinOSHA standards.

Constructionactivities associatedwith implementingAlternative 3 wouldresult in temporaryand localizedincreases to noiselevels in the StudyArea. Any noisewould be withinOSHA standards.

Constructionactivities associatedwith implementingAlternative 4 wouldresult in temporaryand localizedincreases to noiselevels in the StudyArea. Any noisewould be withinOSHA standards.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Vegetation Resources

The No Action Alternativewould result in theconversion of 3,220 acres ofexisting Terrebonne Basinbarrier island beach, duneand marsh wetlandvegetation habitats to openwater bottom habitat overthe 50-year period ofanalysis.

Alternative 5 (NERPlan) would initiallyrestore a total of 5,840acres on Raccoon,Whiskey, Trinity, andTimbalier Islands. Thiswould include initialrestoration of a total of472 acres of dune,4,320 acres ofsupratidal and 1,048acres of intertidalvegetated habitats usedby fish and wildlife forshelter, nesting,feeding, roosting, cover,nursery, and other liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation.

The direct impact tovegetation resourcesof implementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), includinginitial restoration of atotal 1,272 acres with65 acres of dune, 830acres of supratidal,377 acres of intertidalvegetation resourceson Whiskey Island

The direct impacts tovegetation resourcesof implementingAlternative 2 wouldbe similar to thosedescribed for theTimbalier Islandcomponent ofAlternative 5 (NERPlan), includinginitial restoration of atotal 2,630 acres with215 acres of dune,2,346 acres ofsupratidal, 69 acres ofintertidal vegetationresources onTimbalier Island

The direct impacts tovegetation resourcesof implementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponent ofAlternative 5 (NERPlan), includinginitial restoration of atotal 3,902 acres with280 acres of dune,3,176 acres ofsupratidal, 446 acresof intertidalvegetation resourceson Whiskey andTimbalier Islands.

The direct impacts tovegetation resourcesof implementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponent ofAlternative 5 (NERPlan), includinginitial restoration of atotal 5,051 acres with409 acres of dune,3,632 acres ofsupratidal, 1,010acres of intertidalvegetation resourceson Whiskey, Trinityand TimbalierIslands.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Wildlife and Habitat

The No Action Alternativewould continue to degrade,fragment and eventuallyconvert 3,220 acres ofexisting Terrebonne Basinbarrier island beach, duneand intertidal wildlifehabitats to marinedominated open waterbottom habitat over the 50-year period of analysis. Theloss of existing barrierisland and adjacentestuarine wildlife habitatswould adversely impactimportant transitionalhabitat between estuarineand marine environments;essential fish habitat (EFH);unique wildlife habitat (e.g.,nursery, nesting, feeding,and roosting habitats); andcritical wintering habitat forthe threatened pipingplover.

The impacts ofimplementingAlternative 5 (NER)would be a net increaseof 2,781 acres with2,883 AAHUs ofimportant andessential vegetatedwildlife habitats usedby fish and wildlife forshelter, nesting,feeding, roosting, cover,nursery and other liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation.

The impacts ofimplementingAlternative 11 wouldbe a net increase of527 acres with 678AAHUs of importantand essentialvegetated wildlifehabitats used by fishand wildlife forshelter, nesting,feeding, roosting,cover, nursery andother liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation.

The impacts ofimplementingAlternative 11 wouldbe a net increase of1,324 acres with 1,100AAHUs of importantand essentialvegetated wildlifehabitats used by fishand wildlife forshelter, nesting,feeding, roosting,cover, nursery andother liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation.

The impacts ofimplementingAlternative 11 wouldbe a net increase of1,851acres with 1,778AAHUs of importantand essentialvegetated wildlifehabitats used by fishand wildlife forshelter, nesting,feeding, roosting,cover, nursery andother liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation.

The impacts ofimplementingAlternative 11 wouldbe a net increase of2,140 acres with 2,406AAHUs of importantand essentialvegetated wildlifehabitats used by fishand wildlife forshelter, nesting,feeding, roosting,cover, nursery andother liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition between

resident and nonresident fish andwildlife species for

limited coastalvegetation.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Benthic

Although conversion of3,220 acres of existingbarrier habitat and anunknown acreage ofadjacent estuarine habitatsto water bottoms wouldprovide additional habitatfor benthic organisms, theconversion would decreaseavailable nutrients anddetritus and result in theconversion of primarilyestuarine-dependent benthicspecies assemblages to moremarine-dominated and openwater benthic speciesassemblages

Initial construction ofAlternative 5 (NERPlan) would directlyimpact a total of 2,498acres of borrow sitewater bottoms andbenthic organismsutilizing these areas.Renourishment woulddirectly impact a totalof 1,222 acres.A total of 3,283 acres ofexisting water bottomswould be converted tobeach, dune and marshbarrier habitats duringinitial construction.Renourishment wouldimpact 1,633 acres ofwater bottoms andassociated benthicorganisms.

Initial construction ofAlternative 11 woulddirectly impact a totalof 535 acres of borrowsite water bottomsand benthicorganisms utilizingthese areas.Renourishment woulddirectly impact a totalof 859 acres.A total of 469 acres ofexisting waterbottoms would beconverted to beach,dune and marshbarrier habitatsduring initialconstruction.Renourishment wouldimpact 823 acres ofwater bottoms andassociated benthicorganisms.

Initial construction ofAlternative 2 woulddirectly impact a totalof 1,375 acres ofborrow site waterbottoms and benthicorganisms utilizingthese areas.Renourishment woulddirectly impact a totalof 26 acres.A total of 1,675 acresof existing waterbottoms would beconverted to beach,dune and marshbarrier habitatsduring initialconstruction.Renourishment wouldimpact 202 acres ofwater bottoms andassociated benthicorganisms.

Initial construction ofAlternative 3 woulddirectly impact a totalof 1,535 acres ofborrow site waterbottoms and benthicorganisms utilizingthese areas.Renourishment woulddirectly impact a totalof 885 acres.A total of 1,535 acresof existing waterbottoms would beconverted to beach,dune and marshbarrier habitatsduring initialconstruction.Renourishment wouldimpact 1,025 acres ofwater bottoms andassociated benthicorganisms.

Initial construction ofAlternative 4 woulddirectly impact a totalof 1,998 acres ofborrow site waterbottoms and benthicorganisms utilizingthese areas.Renourishment woulddirectly impact a totalof 1,108 acres.A total of 2,729 acresof existing waterbottoms would beconverted to beach,dune and marshbarrier habitatsduring initialconstruction.Renourishment wouldimpact 1,562 acres ofwater bottoms andassociated benthicorganisms.

Plankton

Continued degradation andloss of barrier wetlandseventually result indecrease of availablenutrients and detritus,which could lead to theconversion of primarilyestuarine-dependentplankton speciesassemblages to more marineand open water planktonspecies assemblages.

The direct impacts toplankton resources ofimplementingAlternative 5 (NERPlan) would belocalized and shortterm adverse impacts,including mortality ofsome planktonpopulations, due toconstruction activitiesof terminal groin atRaccoon Island,dredging activities atborrow sites as well asplacement of borrow forbarrier islandrestoration.

The direct impacts toplankton resources ofimplementingAlternative 11 wouldbe localized and shortterm adverse impacts,including mortality ofsome planktonpopulations, due toconstruction activitiesof terminal groin atRaccoon Island,dredging activities atborrow sites as well asplacement of borrowfor barrier islandrestoration.

The direct impacts toplankton resources ofimplementingAlternative 2 wouldbe localized and shortterm adverse impacts,including mortality ofsome planktonpopulations, due toconstruction activitiesof terminal groin atRaccoon Island,dredging activities atborrow sites as well asplacement of borrowfor barrier islandrestoration.

The direct impacts toplankton resources ofimplementingAlternative 3 wouldbe localized and shortterm adverse impacts,including mortality ofsome planktonpopulations, due toconstruction activitiesof terminal groin atRaccoon Island,dredging activities atborrow sites as well asplacement of borrowfor barrier islandrestoration.

The direct impacts toplankton resources ofimplementingAlternative 4 wouldbe localized and shortterm adverse impacts,including mortality ofsome planktonpopulations, due toconstruction activitiesof terminal groin atRaccoon Island,dredging activities atborrow sites as well asplacement of borrowfor barrier islandrestoration.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Fisheries

Conversion of existingbarrier island habitats towater bottom habitat wouldinclude degradation and lossof important essential fishhabitats, especiallytransitional habitat betweenestuarine and marineenvironments, and wouldincrease inter- and intraspecific competition betweenresident and migratory fish.As open water replacesbarrier and estuarinewetland habitats and theextent of marsh-to-waterinterface begins to decrease,fishery productivity is likelyto decline.

Impacts ofimplementingAlternative 5 (NERPlan) would be a netincrease of 2,781 acresof transitional barrierhabitats with 2,883AAHUs of importantand essentialtransactional habitatsused by fish andwildlife for shelter,nesting, feeding,roosting, cover,nursery, and other liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation

Impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NER)including a netincrease of 527 acresof transitional barrierhabitats with 678AAHUs. In addition,Alternative 11 wouldrestore WhiskeyIsland to its minimalgeomorphologic formwhich wouldcontribute to itsecological function ofpreventing conversionof the adjacentTerrebonne Basinestuarine wetlands toopen water habitatthereby maintainingimportant transitionalestuarine habitat forfisheries resources.

Impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theTimbalier Islandcomponent ofAlternative 5 (NER)including a netincrease of 1,324 acresof transitional barrierhabitats with 678AAHUs. In addition,Alternative 2 wouldrestore TimbalierIsland to its minimalgeomorphologic formwhich wouldcontribute to itsecological function ofpreventing conversionof the adjacentTerrebonne Basinestuarine wetlands toopen water habitatthereby maintainingimportant transitionalestuarine habitat forfisheries resources.

Impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NER)including a netincrease of 1,851 acresof transitional barrierhabitats with 1,778AAHUs. In addition,Alternative 3 wouldrestore Whiskey andTimbalier Islands totheir minimalgeomorphologic formwhich wouldcontribute to theirecological function ofpreventing conversionof the adjacentTerrebonne Basinestuarine wetlands toopen water habitatthereby maintainingimportant transitionalestuarine habitat forfisheries resources.

Indirect impacts ofimplementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponents ofAlternative 5 (NER)including a netincrease of 2,140 acresof transitional barrierhabitats with 2,406AAHUs. In addition,Alternative 4 wouldrestore Whiskey,Trinity and TimbalierIslands to their

minimal

geomorphologic formwhich would

contribute to theirecological function ofpreventing conversionof the adjacentTerrebonne Basinestuarine wetlands toopen water habitatthereby maintainingimportant transitionalestuarine habitat forfisheries resources.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Essential Fish Habitat

Approximately 1,560 acresof existing intertidal backbarrier marsh from theseven barrier island system,a more productive categoryof EFH, would be convertedto marine-dominated waterbottoms, a less productiveEFH category. This losswould continue to adverselyimpact essential spawning,nursery, nesting, andforaging habitats forcommercially andrecreationally importantspecies of finfish andshellfish, as well as otheraquatic organisms.

Disruption of the Gulfof Mexico marinehabitat EFH associatedwith borrow areaswould temporarilydisplace the fisherythat inhabitants thereefs and hard sandbottoms. Fisheryorganisms would likelyuse the borrow areasshortly after dredgingactivities cease.Benthic organismswould recolonize theborrow areas withinone to two years.Impacts ofimplementingAlternative 5 (NERPlan) would be a netincrease of 2,781 acresof transitional barrierhabitats with 2,883AAHUs of importantand essentialtransitional habitatsused by fish andwildlife for shelter,nesting, feeding,roosting, cover,nursery, and other liferequirements;increased vegetationgrowth andproductivity; andreduced inter- andintra-specific speciescompetition betweenresident and nonresident fish andwildlife species forlimited coastalvegetation.

Impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NER)including a netincrease of 527 acresof transitional barrierhabitats with 678AAHUs.

Impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theTimbalier Islandcomponent ofAlternative 5 (NER)including a netincrease of 1,324 acresof transitional barrierhabitats with 678AAHUs.

Impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NER)including a netincrease of 1,851 acresof transitional barrierhabitats with 1,778AAHUs.

Indirect impacts ofimplementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponents ofAlternative 5 (NER)including a netincrease of 2,140 acresof transitional barrierhabitats with 2,406AAHUs.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Threatened & EndangeredSpecies

The No Action Alternativewould result in thecontinued degradation andloss of designated criticalwintering habitat and itsprimary constituents for thethreatened piping plover.Other listed species couldalso be adversely impactedby the loss of the barrierislands including: Gulfsturgeon, green sea turtle,hawksbill sea turtle, KempsRidley sea turtle,leatherback sea turtle,loggerhead sea turtle, andthe West Indian manatee.

Alternative 5 (NERPlan) would initiallyrestore a total of 3,730acres of piping plovercritical winteringhabitat over the fourbarrier islands.Impacts to pipingplovers will be avoidedby deterring the birdsfrom nesting on theislands prior toconstructions. Impactsto West IndianManatees will beavoided byimplementing amonitoring andavoidance plan duringconstruction. Impactsto sea turtles will beavoided by utilizing acutterhead dredgerather than a hopperdredge.

Impacts to listedspecies or theirdesignate criticalhabitat would besimilar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), includinginitial restoration of624 acres of pipingplover criticalwintering habitat onWhiskey Island.

Impacts to listedspecies or theirdesignate criticalhabitat would besimilar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), includinginitial restoration of2,053 acres of pipingplover criticalwintering habitat onTimbalier Island.

Impacts to listedspecies or theirdesignate criticalhabitat would besimilar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), includinginitial restoration of624 acres of pipingplover criticalwintering habitat onWhiskey Island and2,053 acres of pipingplover criticalwintering habitat onTimbalier Island.

Impacts to listedspecies or theirdesignate criticalhabitat would besimilar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NERPlan), includinginitial restoration of624 acres of pipingplover criticalwintering habitat onWhiskey Island, 2,053acres of piping plovercritical winteringhabitat on TimbalierIsland, and 434 acresof piping plovercritical winteringhabitat on TrinityIsland.

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Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Cultural & Historic Resources

As the barrier islands andinterior marshes erodeand/or subside, prehistoriccultural resources couldbecome exposed to elementsor inundated, putting themat a greater risk of damageor destruction.

A Phase I submergedcultural resourcesremote sensinginvestigation wasconducted within thevicinity of WhiskeyIsland. Thirteentargets exhibitingpotential culturalresources wereidentified. There willbe no direct impacts tohistoric properties ifthe targetsrepresenting potentialhistoric properties areavoided.No historic propertieshave been identified inthe Raccoon, Timbalieror Trinity Island APE;therefore, no directimpacts to historicproperties areanticipated.The South Pelto, ShipShoal, Whiskey 3A ,Raccoon Island, andNew Cut Borrow Areashave been investigated,and targetsrepresentingpotentially significantcultural resources willbe avoided.

A Phase I submergedcultural resourcesremote sensinginvestigation wasconducted within thevicinity of WhiskeyIsland. Thirteentargets exhibitingpotential culturalresources wereidentified. There willbe no direct impactsto historic propertiesif the targetsrepresenting potentialhistoric properties areavoided.The Whiskey 3A andShip Shoal BorrowAreas have beeninvestigated, andtargets representingpotentially significantcultural resources willbe avoided

No historic propertieshave been identifiedin the TimbalierIsland APE; therefore,no direct impacts tohistoric properties areanticipated.The South Pelto,Whiskey 3A and ShipShoal Borrow Areashave beeninvestigated, andtargets representingpotentially significantcultural resources willbe avoided.

The impacts ofAlternative 3 will beequivalent toAlternatives 11 and 2.The South Pelto,Whiskey 3A, Raccoon,and Ship ShoalBorrow Areas havebeen investigated,and targetsrepresentingpotentially significantcultural resources willbe avoided.

A Phase I submergedcultural resourcesremote sensinginvestigation wasconducted within thevicinity of WhiskeyIsland. Thirteentargets exhibitingpotential culturalresources wereidentified. There willbe no direct impactsto historic propertiesif the targetsrepresenting potentialhistoric properties areavoided.No historic propertieshave been identifiedin the Timbalier orTrinity Island APE;therefore, no directimpacts to historicproperties areanticipated.The South Pelto,Whiskey Island ,Raccoon Island, andNew Cut BorrowAreas have beeninvestigated, andtargets representingpotentially significantcultural resources willbe avoided

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(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Aesthetics

Without implementation ofthe barrier restorationfeatures, existing conditionswill persist resulting in thecontinued loss anddegradation of the barrierislands. Degradation of thebarrier islands wouldconvert existing views ofbeach, dune, and wetland tomore open water views.

Impacts to visualresources wouldprimarily result fromnewly created highquality emergentwetland viewscapesthat would provide along-term visualenhancement of anarea that is presentlyexperiencing a declinein visual complexity.There may be someperceived visualdisturbance as anunnatural terminalgroin structure isplaced at the end ofRaccoon Island.

Impacts similar toAlternative 5 (NERPlan) except that noterminal groin wouldbe constructed.

Impacts similar toAlternative 5 (NERPlan) except that noterminal groin wouldbe constructed.

Impacts similar toAlternative 5 (NERPlan) except that noterminal groin wouldbe constructed.

Impacts similar toAlternative 5 (NERPlan) except that noterminal groin wouldbe constructed.

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Recreation

As existing barrier islandsare lost and freshwaterwetland/marsh areastransition to saltwatermarsh, and subsequently toopen water, the recreationalopportunities would changeaccordingly. As populationsof freshwater and/orsaltwater species decline, sowould fishing opportunities.In transitional and uplandareas where populations ofgame species exist, huntingopportunities would bereduced as the landscapebecame less supportive ofthose species. The sameholds true for thepopulations of migratorywaterfowl and other birdspecies, which will affectopportunities for viewing

Impacts ofimplementingAlternative 5 (NERPlan) would be a netincrease of 2,781 acresof transitionalestuarine wetlands.Following construction,these transitionalestuarine wetlands willprovide important andessential fish andwildlife habitats thatwill contribute torestoring and nurturingthe food chain for theorganisms that providethe base forrecreational activitiessuch as fishing, wildlifeviewing, and camping.Increased opportunityfor recreationalactivities will comefrom expansion of newvegetative habitat onnewly created areasand the protection fromstorm-related stressorsthat the restored beach,dune, and marsh areaswill afford adjacentexisting habitats.

Impacts torecreational resourceswould be similar tothose described forthe Whiskey Islandcomponent ofAlternative 5 (NERPlan), including a netincrease of 527 acresof transitionalestuarine wetlands.

Impacts torecreational resourceswould be similar tothose described forthe Whiskey Islandcomponent ofAlternative 5 (NERPlan), including a netincrease of 1,324 acresof transitionalestuarine wetlands.

Impacts torecreational resourceswould be similar tothose described forthe Whiskey Islandcomponent ofAlternative 5 (NERPlan), including a netincrease of 1,851 acresof transitionalestuarine wetlands.

Impacts torecreational resourceswould be similar tothose described forthe Whiskey Islandcomponent ofAlternative 5 (NERPlan), including a netincrease of 2,140 acresof transitionalestuarine wetlands.

Population and Housing Study area is remote and uninhabited. Study area is remote and uninhabited. Study area is remote and uninhabited. Study area is remote and uninhabited. Study area is remote and uninhabited. Study area is remote and uninhabited.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Employment and Income

Study area is remote anduninhabited, employmentand income primarilyrelated to oil and gas andcommercial fisheries andwhich may locally decreasedue to barrier habitatdegradation and loss.

Alternative 5 (NER)will protect, create andnourish essential fishand wildlife habitatsthat will contribute torestoring and nurturingthe food chain for theorganisms that providethe base for commercialand recreationalactivities such asfishing and ecotourism.Restored and protectedwetlands could obviatethe need forabandonment orrelocation of otherwisevulnerable oil and gasfacilities, and theemploymentopportunities thataccompany them.

Implementing thissingle islandalternative wouldprovide limitedbenefits to commercialand recreationalfisheries by increasingthe quantity andquality of essentialfish habitat availablefor nursery and otheraquatic life functions.In addition thisalternative providessome protection ofadjacent oyster leasesfrom being directlyexposed to the highersaline waters of theGulf

Impacts similar toAlternative 11.

Impacts similar toAlternative 5 (NERPlan).

Impacts similar toAlternative 5 (NERPlan).

Community Cohesion

The No Action Alternativemay have cumulativeimpacts on communitycohesion if the islandscontinue to erode to thepoint where the interiorwetlands cease to protectthe upland communities.

By slowing wetlandloss and retaining theprotective function ofthe barrier islandscommunities dependenton the basin resourceswould be less likely tolose cohesion andcommunity identity.

Impacts similar toAlternative 5 (NERPlan), but to a muchlesser extent.

Impacts similar toAlternative 5 (NERPlan), but to a muchlesser extent.

Impacts similar toAlternative 5 (NERPlan), but to a lesserextent.

Impacts would besimilar to Alternative5 (NER), but ofreduced scope, since itonly involves threeislands

Environmental Justice

There would be no impact ofthe No Action Alternativeon environmental justice, asthis concept is inapplicablewithin the Study Area. TheStudy Area is undevelopedand uninhabited.

There would be nodirect impact ofAlternative 5 (NER) onenvironmental justice,as this concept isinapplicable within theStudy Area. The StudyArea is undevelopedand uninhabited.

There would be nodirect impact ofAlternative 11 onenvironmental justice,as this concept isinapplicable withinthe Study Area. TheStudy Area isundeveloped anduninhabited.

There would be nodirect impact ofAlternative 2 onenvironmental justice,as this concept isinapplicable withinthe Study Area. TheStudy Area isundeveloped anduninhabited.

There would be nodirect impact ofAlternative 3 onenvironmental justice,as this concept isinapplicable withinthe Study Area. TheStudy Area isundeveloped anduninhabited.

There would be nodirect impact ofAlternative 4 onenvironmental justice,as this concept isinapplicable withinthe Study Area. TheStudy Area isundeveloped anduninhabited.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Infrastructure

The existing privateinfrastructure includes oiland gas pipelines; storagetank batteries, platforms,and wellheads. The effectsof continued barrier islandloss and degradation willlead to increased costs formaintenance and repair ofthe existing infrastructure,reduced level of oil and gasinfrastructure development,and possible relocation ofsome existing oil and gasassets.

Implementing the NERPlan would provideprotection to theprivate infrastructureon and adjacent to thefour islands. Due to theplanned renourishmentevents, this protectionshould last for theduration of the 50-yearperiod of analysis.Appropriate safetyprecautions will beimplemented for thisand all otheralternatives to avoidpotential constructionrelated impacts toexisting infrastructure.

ImplementingAlternative 11 wouldprovide protection tothe existinginfrastructure in theimmediate area ofWhiskey Island forthe 50-year period ofanalysis, due to theproposedrenourishment eventsare undertaken inTY20 and TY40.Appropriate safetyprecautions will beimplemented for thisand all otheralternatives to avoidpotentialconstruction-relatedimpacts to existinginfrastructure.

ImplementingAlternative 2 wouldprovide protection tothe extensive existinginfrastructure in theimmediate area ofTimbalier Island forthe 50-year period of,due to therenourishment eventis undertaken inTY30.Appropriate safetyprecautions will beimplemented for thisand all otheralternatives to avoidpotentialconstruction-relatedimpacts to existinginfrastructure.

Impacts would be acombination ofAlternatives 11 and 2.

The impacts would besimilar to Alternative5 (NER), but to asomewhat lesserextent benefit becauseAlternative 4 onlyinvolves three islands.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Business and Industry

The primary industry in theStudy Area involves oil andgas extraction, processing,and transmission. Theeffects of continued barrierisland loss and degradationwill lead to increasedmaintenance costs forexisting oil and gasinfrastructure, reduced levelof oil and gas infrastructuredevelopment, and relocationof some existing oil and gasassets. Impact to thecommercial fisherybusinesses will result fromthe gradual decline inabundance of the targetresources which will requireadjustment to other targetspecies or relocation to othermore productive fishinggrounds.

The NER Plan willprovide protection tothe industrialinfrastructure on andadjacent to the fourislands. In addition therestored marshes willcontinue to provide theshelter and nurseryfunctions required bythe estuary-dependentfishery resources.

Whiskey Island doesnot protect anyindustrialinfrastructure, so thedirect impact of itsrestoration will benegligible. However,restoration of themarsh and itsprotective beach anddune will provide abenefit to the fisheryresources similar toAlternative 5 (NER),but at a reduced scale.

The impacts ofimplementingAlternative 2 wouldbe similar toAlternative 11. Inaddition, TimbalierIsland protects asignificant amount ofindustrialinfrastructure fromdirect impact from theGulf of Mexico and,similarly to WhiskeyIsland, the restoredmarsh and itsprotective beach anddune will provide abenefit to fisheryresources.

The impacts ofimplementingAlternative 3 wouldbe similar toAlternative 5 (NER)but to a lesser extentbecause Alternative 3only involves twoislands. However,Timbalier Island hasextensive industrialinfrastructure thatwould be protected.

The impacts ofimplementingAlternative 4 wouldbe similar toAlternative 5 (NER)but to a somewhatlesser extent becauseAlternative 3 onlyinvolves three islands.However, TimbalierIsland has extensiveindustrialinfrastructure thatwould be protected.

Traffic and Transportation

The Study Area consists of aseries of remote,uninhabited barrier islands,accessible only by shoaldraft boat or aircraft. Thereis no public or privatetransportationinfrastructure. There wouldbe no direct impacts of theNo Action on traffic andtransportation, as thisfeature does not exist withinthe Study Area.

There is no public orprivate transportationinfrastructure in theStudy Area.

There is no public orprivate transportationinfrastructure in theStudy Area.

There is no public orprivate transportationinfrastructure in theStudy Area.

There is no public orprivate transportationinfrastructure in theStudy Area.

There is no public orprivate transportationinfrastructure in theStudy Area.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Public Facilities & Services

There are no public facilitiesor public services on theislands.Three of the islands,Raccoon, Whiskey, andWine Islands, are managedas a wildlife refuge by theLouisiana Department ofWildlife and Fisheries,however trespass isprohibited.

There are no publicfacilities or publicservices on the islands.

There are no publicfacilities or publicservices on theislands.

There are no publicfacilities or publicservices on theislands.

There are no publicfacilities or publicservices on theislands.

There are no publicfacilities or publicservices on theislands.

Local Government Finance

There are no localgovernment expendituresfor public services on theislands.

There are no localgovernmentexpenditures for publicservices on the islands.

There are no localgovernmentexpenditures forpublic services on theislands.

There are no localgovernmentexpenditures forpublic services on theislands.

There are no localgovernmentexpenditures forpublic services on theislands.

There are no localgovernmentexpenditures forpublic services on theislands.

Tax Revenue & Property Values

The islands arepredominately owned by theState; No taxes are assessedon these properties. Thereare a few parcels of privatelandowners on Trinity,Timbalier, and EastTimbalier. However, thetaxable values andassociated revenues areminimal.

Tax revenues andproperty values wouldnot significantly changeby the construction ofAlternative 5 (NERPlan).

Tax revenues andproperty values wouldnot significantlychange by theconstruction ofAlternative 11.

Tax revenues andproperty values wouldnot significantlychange by theconstruction ofAlternative 2,

Tax revenues andproperty values wouldnot significantlychange by theconstruction ofAlternative 3.

Tax revenues andproperty values wouldnot significantlychange by theconstruction ofAlternative 4.

Community and RegionalGrowth

There would be no direct,impacts of the No ActionAlternative on communityand regional growth, asthese features do not existwithin the Study Area.

There would be nodirect, impacts ofAlternative 5 (NERPlan) on communityand regional growth, asthese features do notexist within the StudyArea.

There would be nodirect, impacts ofAlternative 11 oncommunity andregional growth, asthese features do notexist within the StudyArea.

There would be nodirect, impacts ofAlternative 2 oncommunity andregional growth, asthese features do notexist within the StudyArea.

There would be nodirect, impacts ofAlternative 3 oncommunity andregional growth, asthese features do notexist within the StudyArea.

There would be nodirect, impacts ofAlternative 4 oncommunity andregional growth, asthese features do notexist within the StudyArea.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Agriculture

There would be no directimpacts of the No ActionAlternative on agricultureor silviculture land use, asthese uses do not existwithin the Study Area.

There would be nodirect impacts of theAlternative 5 (NERPlan) on agriculture orsilviculture land use, asthese uses do not existwithin the Study Area.

There would be nodirect impacts of theAlternative 11 onagriculture orsilviculture land use,as these uses do notexist within the StudyArea.

There would be nodirect impacts of theAlternative 2 onagriculture orsilviculture land use,as these uses do notexist within the StudyArea.

There would be nodirect impacts of theAlternative 3 onagriculture orsilviculture land use,as these uses do notexist within the StudyArea.

There would be nodirect impacts of theAlternative 4 onagriculture orsilviculture land use,as these uses do notexist within the StudyArea.

Forestry

There would be no directimpacts of the No ActionAlternative on forestry landuse, as these uses do notexist within the Study Area.

There would be nodirect impacts of theAlternative 5 (NERPlan) on forestry landuse, as these uses donot exist within theStudy Area.

There would be nodirect impacts of theAlternative 11 onforestry land use, asthese uses do not existwithin the StudyArea.

There would be nodirect impacts of theAlternative 2 onforestry land use, asthese uses do not existwithin the StudyArea.

There would be nodirect impacts of theAlternative 3 onforestry land use, asthese uses do not existwithin the StudyArea.

There would be nodirect impacts of theAlternative 4 onforestry land use, asthese uses do not existwithin the StudyArea.

Public Lands

Since the islands arepredominately owned by theState, the continueddegradation and eventualdisappearance of the islandswill reduce the amount ofpublic lands in the StudyArea.

The impacts ofimplementingAlternative 5 (NER)would be a net increaseof 2,781 acres with2,883 AAHUs ofimportant andessential vegetatedwildlife habitats onpublic lands.

The impacts ofimplementingAlternative 11 wouldbe a net increase of527 acres with 678AAHUs of importantand essentialvegetated wildlifehabitats used by fishand wildlife habitatson public lands.

The impacts ofimplementingAlternative 11 wouldbe a net increase of1,324 acres with 1,100AAHUs of importantand essentialvegetated wildlifehabitats used by fishand wildlife habitatson public lands.

The impacts ofimplementingAlternative 11 wouldbe a net increase of1,851acres with 1,778AAHUs of importantand essentialvegetated wildlifehabitats on publiclands.

The impacts ofimplementingAlternative 11 wouldbe a net increase of2,140 acres with 2,406AAHUs of importantand essentialvegetated wildlifehabitats on publiclands.

Water Use and Supply

There are no water supplyfacilities within the StudyArea.

There are no watersupply facilities withinthe Study Area.

There are no watersupply facilitieswithin the StudyArea.

There are no watersupply facilitieswithin the StudyArea.

There are no watersupply facilitieswithin the StudyArea.

There are no watersupply facilitieswithin the StudyArea.

Navigation

The continued wetland lossmay affect navigability andmaintenance of both thefederally- and privatelymaintained waterways,including the HoumaNavigation Canal andseveral smaller bayous.

The impacts ofimplementing theAlternative 5 (NERPlan) would betemporary disruption ofrecreational andcommercial vesseltraffic in the vicinity ofeach island and borrowarea duringconstruction.

The impacts ofimplementing theAlternative 11 wouldbe temporarydisruption ofrecreational andcommercial vesseltraffic in the vicinityof each island andborrow area duringconstruction.

The impacts ofimplementing theAlternative 2 wouldbe temporarydisruption ofrecreational andcommercial vesseltraffic in the vicinityof each island andborrow area duringconstruction.

The impacts ofimplementing theAlternative 3 wouldbe temporarydisruption ofrecreational andcommercial vesseltraffic in the vicinityof each island andborrow area duringconstruction.

The impacts ofimplementing theAlternative 4 wouldbe temporarydisruption ofrecreational andcommercial vesseltraffic in the vicinityof each island andborrow area duringconstruction.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Oil, Gas, Utilities, Pipelines

The No Action Plan wouldresult in the persistence ofexisting conditionsincluding the fragmentationand degradation of theexisting barrier islands andinland marshes. Theunimpeded erosion of theseareas will continue touncover pipelines that havebeen buried both on theislands and on the seafloor.As these pipelines areexposed, they will becomesusceptible weathering, boatcollisions, and impacts fromanchor dragging.

The construction of theAlternative 5 (NERPlan) will benefit thepipelines on the fourislands by furthercovering them with fillmaterial. This willprovide a protectivebarrier from weatherrelated impacts as wellas impacts associatedwith the day-to-dayoperation of the oil andgas facilities.Impacts to pipelines inthe borrow areas arehighly unlikely a bufferzone will be applied toeach pipeline to provideadditional protectionduring construction.

There are no oil andgas pipelines orinfrastructure locatedwithin the proposedtemplate forAlternative 11(Whiskey Island).Therefore, placementof fill on the islandwill not have anydirect impacts on oiland gas activitiesImpacts to pipelinesin the borrow areasare highly unlikely abuffer zone will beapplied to eachpipeline to provideadditional protectionduring construction.

Construction ofAlternative 2 willdirectly benefit thetwo active pipelinesthat are on TimbalierIsland by furthercovering them will fillmaterial. This willprovide a protectivebarrier from weatherrelated impacts aswell as impactsassociated with theday-to-day operationof the oil and gasfacilitiesImpacts to pipelinesin the borrow areasare highly unlikely abuffer zone will beapplied to eachpipeline to provideadditional protectionduring construction.

There is no oil andgas infrastructure onWhiskey Island.Construction ofTimbalier Plan E,however, will directlybenefit the two activepipelines that are onthe island by furthercovering them will fillmaterial andproviding a protectivebarrier.Impacts to pipelinesin the borrow areasare highly unlikely abuffer zone will beapplied to eachpipeline to provideadditional protectionduring construction.

There is no oil andgas infrastructure onWhiskey or TrinityIsland. Constructionof Timbalier Plan E,however, will directlybenefit the two activepipelines that are onthe island by furthercovering them will fillmaterial andproviding a protectivebarrier.Impacts to pipelinesin the borrow areasare highly unlikely abuffer zone will beapplied to eachpipeline to provideadditional protectionduring construction.

Flood Control and HurricaneProtection

There are no flood controlstructures within or nearbythe Study Area.

There are no floodcontrol structureswithin or nearby theStudy Area. However,construction ofAlternative 5 (NERPlan) will help toprotect the mainlandfrom storm surge andwave impacts.

There are no floodcontrol structureswithin or nearby theStudy Area.However, constructionof Alternative 11 willhelp to protect themainland from stormsurge and waveimpacts.

There are no floodcontrol structureswithin or nearby theStudy Area.However, constructionof Alternative 2 willhelp to protect themainland from stormsurge and waveimpacts.

There are no floodcontrol structureswithin or nearby theStudy Area.However, constructionof Alternative 3 willhelp to protect themainland from stormsurge and waveimpacts.

There are no floodcontrol structureswithin or nearby theStudy Area.However, constructionof Alternative 4 willhelp to protect themainland from stormsurge and waveimpacts.

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Commercial Fisheries

The continued wetlandhabitat losses within theStudy Area, combined withwidespread coastal wetlandloss throughout coastalLouisiana, would contributeto the overall decrease inproductivity of Louisianascoastal fisheries.

Impacts ofimplementingAlternative 5 (NERPlan) would be a netincrease of 2,781 acresof transitional barrierhabitats with 2,883AAHUs of importantand essential habitatsused by fish for shelter,nesting, feeding, andother life requirements.The indirect impactfrom implementing theNER would be atemporary disruption ofcommercial fishingvessel traffic in thevicinity of the dredgeover the borrow areaduring construction.

Impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theWhiskey Islandcomponent ofAlternative 5 (NER)including a netincrease of 527 acresof transitional barrierhabitats with 678AAHUs of importantand essential habitatsused by fish forshelter, nesting,feeding, and other liferequirements.

Impacts ofimplementingAlternative 11 wouldbe similar to thosedescribed for theTimbalier Islandcomponent ofAlternative 5 (NER)including a netincrease of 1,324 acresof transitional barrierhabitats with 678AAHUs of importantand essential habitatsused by fish forshelter, nesting,feeding, and other liferequirements.

Impacts ofimplementingAlternative 3 wouldbe similar to thosedescribed for theWhiskey andTimbalier Islandscomponents ofAlternative 5 (NER)including a netincrease of 1,851 acresof transitional barrierhabitats with 678AAHUs of importantand essential habitatsused by fish forshelter, nesting,feeding, and other liferequirements.

Indirect impacts ofimplementingAlternative 4 wouldbe similar to thosedescribed for theWhiskey, Trinity andTimbalier Islandscomponents ofAlternative 5 (NER)including a netincrease of 2,140 acresof transitional barrierhabitats with 2,406AAHUs transitionalbarrier habitats with678 AAHUs ofimportant andessential habitatsused by fish forshelter, nesting,feeding, and other liferequirements.

Oyster Leases

The ongoing loss of wetlandsin the Study Area wouldalter the detritus-based foodweb of the oyster therebyreducing the localizedcarrying capacity of theoyster leases in the area.

The immediate directimpacts of Alternative5 (NER Plan) wouldinclude disturbance towater bottoms from theplacement of dredgedmaterial. Onceconstruction iscompleted the directimpact of implementingthe NER Plan would bestabilization of thebarrier islands, thusproviding additionalsheltered habitat foroyster settlement, andcreation of additionalmarsh habitat, leadingto increased productionof detritus andcatabolic compounds.

Impacts would besimilar to Alternative5 (NER Plan), but to amuch lesser extentsince only one islandis being restored(Whiskey).

Impacts would besimilar to Alternative5 (NER Plan), but to amuch lesser extentsince only one islandis being restored(Timbalier).

Impacts would besimilar to Alternative5 (NER Plan), but to alesser extent sinceonly two islands arebeing restored(Whiskey andTimbalier).

Impacts would besimilar to Alternative5 (NER Plan), but to alesser extent sincethree islands arebeing restored(Whiskey, Trinity,and Timbalier).

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

HTRW

Based on current andhistorical uses of the StudyArea for oil and gasexploration anddevelopment, there isreason to believe that thepotential to encounterHTRW problems would bemoderate. Furthermore,increased susceptibility ofoil and gas infrastructure tocoastal processes couldincrease the potential forHTRW within the StudyArea

Impacts similar to theNo Action Alternative

Impacts similar to theNo Action Alternative

Impacts similar to theNo Action Alternative

Impacts similar to theNo Action Alternative

Impacts similar to theNo Action Alternative

D. Contributions to Planning ObjectivesbProvide an expanded footprintof minimized barrier islandsection to provide thegeomorphic form and ecologicfunction of the TerrebonneBasin barrier island, reducingvolume loss within the LCATBBSR Study Area below thehistoric average (1880 through2005).

0 2 2222

Restore and improve variousbarrier island habitats thatprovide essential habitats forfish, migratory birds, and otherterrestrial and aquatic species,mimicking, as closely aspossible, conditions whichwould occur naturally in thearea for the 50 year period ofanalysis.

0 2 2222

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No-Action Alternative

Alternative 5

(NER Plan) Alternative 11 Alternative 2 Alternative 3 Alternative 4

Increase sediment input tosupplement longshore sedimenttransport processes along thegulf shoreline by mechanicallyintroducing compatiblesediment, and increasing theability of the restored area tocontinue to function andprovide habitat for the 50 yearperiod of analysis withminimum continuingintervention.

0 2 2222

E. Planning ConstraintsbLack of suitable sediments forrestoration 0 2 2222Environmental impacts ofhuman activities in the StudyArea

0 2 2222

Infrastructure and culturalresources that must be avoidedor relocated

0 2 2222

Limitations in thecharacterization and simulationof environmental processes

0 2 2222

F. Response to Evaluation CriteriabCompleteness 0 2 2 2 2 2Effectiveness 0 2 2 2 2 2Efficiency 0 2 2 2 2 2Acceptability 0 2 2 2 2 2

a. When determining fully funding project costs, the preliminary costs were refined using MCACES. These cost refinements were onlyperformed on the NER Plan and recommended component of construction.b. 0 = Does not meet; 1 = Partial meets; 2 = Meets

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3.9 RISK AND UNCERTAINTY

3.9.1 Simulation Uncertainties

Risks and uncertainties related to the formulation, selection and implementation of

the Study plan have been considered in this study. Uncertainties in the analysis of

the alternatives are associated with the precision of the information on coastal

erosion process and the methods used to assess performance of alternatives.

Physical processes associated with the evolution of coastal landforms are generally

very complex. While the underlying principles controlling these processes are well

understood, reliable simulation of such processes and their interactions (wind and

wave processes, ocean currents, tides, sediment transport, storms) may require very

large amounts of data. In order to analyze the alternatives at an appropriate level

of detail and reliability for selection of the preferred plan, a number of simplifying

assumptions and approaches were used to evaluate the restoration feature

performance for the alternatives. These uncertainties, assumptions and limitations

on reliability of the analyses are provided in the Engineering Appendix. Where

uncertainties are present regarding the particular values to use for certain

processes or conditions in the study, generally, a mid-range value was selected. A

value assignment may be selected that is not at or near the mid point of a range of

estimates where the value can be justified based on the best professional judgment

of the PDT members, or where there is a particular rationale for the value selected,

such as the need for a conservative safety factor in selection of an estimate.

3.9.2 Weather-related Risks

Risks associated with the Study alternatives are primarily related to the possibility

of extreme weather events during the Study period of performance. If a powerful

tropical weather system passes over the Study Area early in the Study life, the

overall performance and benefits of the restoration features may be greatly reduced,

or even eliminated, by such an event. Smaller scale storm events have been

incorporated into estimates of coastal processes, such as shoreline retreat, for

evaluation of the alternatives. The assumptions are based on near-term and longterm historical observations of the frequency of repeat events that are considered

likely to occur during the Study life. While a project could be designed to provide

benefits after impacts of a major storm event, this approach would require costs and

resource commitments that would be unnecessary under conditions that are more

likely to occur during the period of evaluation.

3.9.3 Relative Sea-Level Rise Uncertainties

According to EC-1165-2-211, relative sea-level rise (RSLR) must be considered in

every USACE coastal activity. In order to determine the range of possible future

rates of sea-level rise, the PDT followed an 18-step guidance document developed by

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the USACE (USACE, 2009). The guidance document provides a methodology for

determining a low (historic), intermediate, and high RSLR rate for a particular

Study Area. The intermediate and high rates represent possible future acceleration

of sea-level rise. A flowchart of the steps is provided in Appendix L.

The low RSLR rate was determined using historical data collected at Grand Isle, LA

(http://tidesandcurrents.noaa.gov). Analysis of the data revealed a mean sea level

(MSL) trend of 9.24 mm/year, which is equivalent to a change of 0.030 ft/year. This

estimated MSL trend combines the global MSL rise and a subsidence rate of 0.24

ft/yr. Subsidence was calculated by subtracting the local MSL rise rate from the

regional MSL rate. The future sea-level change values for the low rate were then

determined by extrapolating the historic linear trend into the future.

The eustatic sea-level rise rates for the intermediate and high rates were

determined using the modified NRC Curves I and III, respectively. RSLR rates

were then calculated by summing the eustatic rates and the subsidence rate of 0.24

ft/yr. Table 3-46 presents low/historic, intermediate and high relative sea-level

changes for TY0, TY5, TY10, TY25, and TY50.

Table 3-46. Estimated relative sea-level rise rates

Rate Type Period

Eustatic

SLR

(ft)

Subsidence

(ft)

Relative SLR

(ft)

Low/Historic

2006-2012 (TY0) 0.033 0.144 0.177

2006-2017 (TY5) 0.061 0.264 0.325

2006-2022 (TY10) 0.089 0.384 0.473

2006-2037 (TY25) 0.173 0.744 0.917

2006-2062 (TY50) 0.312 1.344 1.656

Intermediate

(NRC Curve I)

2006-2012 (TY0) 0.055 0.144 0.199

2006-2017 (TY5) 0.105 0.264 0.369

2006-2022 (TY10) 0.159 0.384 0.543

2006-2037 (TY25) 0.343 0.744 1.087

2006-2062 (TY50) 0.729 1.344 2.073

High

(NRC Curve III)

2006-2012 (TY0) 0.124 0.144 0.268

2006-2017 (TY5) 0.246 0.264 0.510

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Rate Type Period

Eustatic

SLR

(ft)

Subsidence

(ft)

Relative SLR

(ft)

2006-2022 (TY10) 0.385 0.384 0.769

2006-2037 (TY25) 0.899 0.744 1.643

2006-2062 (TY50) 2.085 1.344 3.429

During plan formulation, the PDT agreed that the intermediate RSLR rate would

be the most appropriate rate to utilize in the initial development, evaluation, and

screening of the Study alternatives. Consequently, habitat acres, AAHUs, and

erosion rates discussed in the preceding sections of the report are based on this rate.

However, to meet the requirements of EC 1165-2-211, the PDT concurrently

conducted an evaluation of the alternatives utilizing the high and low RSLR rates.

Each of the plans in the Intermediate Array was subjected to low and high RSLR

rates to determine a new set of habitat acres for each target year. Table 3-47

presents a comparison of the average annual habitat acres for the low,

intermediate, and high RSLR rates for the island plans in the NER Plan prior to the

addition of renourishment.

Table 3-47. Comparison of average annual habitat acres for low,

intermediate, and high SLR rates

Rate Type

Average Annual Habitat Acres

Whiskey

Plan C

Trinity

Plan C

Raccoon

Plan E

w/TG

Timbalier

Plan E Total

Low/Historic 968 788 723 2034 4513

Intermediate

(NRC Curve I) 944 777 722 2029 4472

High

(NRC Curve III) 754 634 676 1922 3986

Should the RSLR coincide with the low rates as calculated per EC 1165-2-211,

output will be slightly greater than anticipated. However, should the RSLR equal

the high sea level rise trend, the Study will produce approximately 11% less acres

than anticipated.

As stated above, the EC 1165-2-211 assumes constant subsidence rate. A

comparative analysis of the historic erosion rates adopted for the study and relative

SLR-induced erosion rates expressed in terms of the Bruun Rule presented in

Appendix L, demonstrates that the uncertainties associated with future subsidence

rate are more than accounted for.

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3.9.4 Cost Estimate Uncertainties

In compliance with Engineer Regulation (ER) 1110-2-1302 Civil Works Cost

Engineering, dated September 15, 2008, formal risk analyses studies were

conducted for the development of contingency on the total project cost for the initial

restorations of the NER Plan and recommended component of construction

exclusive of the operation and maintenance construction activities. The purpose of

these risk analyses studies were to establish project contingencies by identifying

and measuring the cost and schedule impact of project uncertainties with respect to

the estimated project cost for the initial restoration of the NER Plan and

recommended component of construction.

A risk analysis begins with the identification of risk factors for the Study. The risks

are then compared for commonalities with other risk factors and a preliminary risk

register is developed for risk level assignment. Following risk level evaluation and

assignment, those risk factor found to have 'moderate' or 'high' impact risks are

carried forward to the final risk register and quantified. The final risk register

serves as the risk models used within the Crystal Ball software.

The fully funded construction costs calculated for the 80% confidence level of

contingency as per USACE Civil Works guidance are shown in Tables 3-48 through

3-50 for the NER Plan and recommended component of construction, respectively.

The fully funded construction cost contingencies for the 50% and 100% confidence

levels are also provided for illustrative purposes. Tables 3-51 and 3-52 present the

fully funded project costs of the initial restoration components for the NER Plan and

recommended component of construction, respectively based on the anticipated

contracts. These costs are intended to address the congressional request of project

cost estimates to implement the Study.

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Table 3-48. NER Plan Initial Restoration - Cost Estimate with

Contingencies Summary (Contract No. 1  Whiskey, Trinity, & Raccoon

Islands)

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

from Risk

Analysis

Total

Contingency

& Escalation

($1,000) 1

Fully

Funded Cost

($1,000) 2

50% Confidence Level -

Initial Restoration

Project Cost

$260,000 17.9% $47,000 $307,000

80% Confidence Level -

Initial Restoration

Project Cost

$260,000 27.4% $71,000 $331,000

100% Confidence Level -

Initial Restoration

Project Cost

$260,000 60.3% $157,000 $417,000

1 Adaptive management plan cost includes prior escalation & contingency and is subjected to the

total contingency and escalation.

2 Costs taken from risk analysis forecasts

Table 3-49. NER Plan Initial Restoration - Cost Estimate with

Contingencies Summary (Contract No. 2 - Timbalier Island)

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

from Risk

Analysis

Total

Contingency

& Escalation

($1,000) 1

Fully

Funded Cost

($1,000) 2

50% Confidence Level -

Initial Restoration

Project Cost

$245,000 19.3% $47,000 $292,000

80% Confidence Level -

Initial Restoration

Project Cost

$245,000 29.4% $72,000 $317,000

100% Confidence Level -

Initial Restoration

Project Cost

$245,000 66.0% $162,000 $407,000

1 Adaptive management plan cost includes prior escalation & contingency and is subjected to the

total contingency and escalation.

2 Costs taken from risk analysis forecast

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Table 3-50. Initial Restoration - Cost Estimate for the Recommended

Component of Construction with Contingencies Summary

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

from Risk

Analysis

Total

Contingency

& Escalation

($1,000) 1

Fully

Funded Cost

($1,000) 2

50% Confidence Level -

Initial Restoration

Project Cost

$90,100 18.4% $16,600 $107,000

80% Confidence Level -

Initial Restoration

Project Cost

$90,100 27.7% $24,990 $115,000

100% Confidence Level -

Initial Restoration

Project Cost

$90,100 59.2% $53,320 $143,000

1 Adaptive management plan cost includes prior escalation & contingency and is subjected to the

total contingency and escalation.

2 Costs taken from risk analysis forecast

Table 3-51. Fully Funded Cost Summary for NER Plan Initial Restoration

Project Element Program

Year Cost

Total

Contingencies

&

Escalations 1

Fully Funded

Total 2

Lands & Damages $545,000 $169,000 $715,000

Fish & Wildlife

(Adaptive Management Plan)

$5,820,000 Included $5,820,000

Breakwaters & Seawalls $1,830,000 $661,000 $2,490,000

Beach Replenishment $463,000,000 $156,000,000 $619,000,000

PED $23,000,000 $6,850,000 $30,000,000

Construction Management $23,000,000 $7,800,000 $31,000,000

NER Initial Restoration

Fully Funded Costs $518,000,000 $171,000,000 $689,000,000

1 Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2 Costs taken from TPCS

Table 3-52. Fully Funded Cost Summary for Initial Restoration of the

Recommended Component of Construction

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Project Element Program

Year Cost

Total

Contingencies

&

Escalations 1

Fully Funded

Total 2

Lands & Damages $51,000 $16,000 $67,000

Fish & Wildlife

(Adaptive Management Plan) $5,820,000 Included $5,820,000

Beach Replenishment $78,000,000 $25,000,000 $103,000,000

PED $3,920,000 $1,120,000 $5,040,000

Construction Management $3,920,000 $1,240,000 $5,160,000

Initial Restoration

Fully Funded Costs $92,000,000 $27,000,000 $119,000,000

1 Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2 Costs taken from TPCS

Additional information on the Risk Analyses are presented in Appendix L.

3.9.5 Recommendations for Future Research

The PDT identified the following research/data collection opportunities that will

improve future barrier island projects:

 Pre-and post-storm survey data to enable SBEACH model verification;

 Updated topographic and bathymetric surveys;

 Analysis of past barrier island restoration projects

 Analysis of physical process of the barrier island system as a whole (sediment

transport model, geomorphic profile models)

 Island specific and system-wide sediment budget

 Quantitative ecological benefits of barrier island restoration on inland

habitats

 Additional modeling to refine our predictive capabilities of the effectiveness of

detached breakwaters, terminal groins and other hard structures

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3.10 IMPLEMENTATION REQUIREMENTS

3.10.1 Schedule

3.10.1.1 Milestones

Table 3-53 presents an anticipated schedule of major milestones for implentation of

the NER Plan.

Table 3-53. Anticipated Schedule of Milestones

Milestones Schedule

Final Report August 2010

Division Engineer Notice August 2010

Washington Level Review August 2010

Execute Cost-Sharing Agreement for PED September 2010

State and Agency Review October 2010

Chief of Engineers Report December 2010

Begin Preconstruction Engineering and Design 2010

ASA and OMB Review 2011

ASA Report to Congress 2011

Complete Design Documentation Report 2011

Complete Plans and Specifications 2011

Execute PPA 2011

Complete Real Estate Acquisition 2011

Advertise Construction 2012

Construction Start 2012

Complete Construction 2016

Turnover Project to Local Sponsor 2016

Initiate Monitoring and Adaptive Management During PED

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Complete Monitoring and Adaptive

Management

2026

3.10.1.2 Design Schedule

The design schedule follows the elements of the PED outlined in Engineering

Regulation ER1110-2-1150 (USACE, 1999) which include: study reformulation;

documentation of design; technical review conference; design documentation

reports; permit applications; value engineering; hazardous, toxic, and radioactive

waste assessments; relocations; physical model studies; preparation of the project

cooperation agreement; preparation of plans and specifications; independent

government estimates; review of NEPA document; and independent technical

review.

On a project following the full normal authorization process, the PED phase begins

when the Major Subordinate Command Commander issues the public notice for the

feasibility report and PED funds are allocated to the district. PED generally

requires a period of up to two years, depending on the complexity of the project, and

ends with completion of the plans and specifications for the first construction

contract or as otherwise defined in the PED cost-sharing agreement. Engineering

functions shall be prepared to begin an intensive effort immediately upon

notification that PED funds are available.

For the LCA TBBSR Study, it is estimated this phase will last approximately 15

months. Time should be saved because the alternatives analysis, fill template

designs, and borrow area identification were completed as part of the engineering

feasibility study. Surveys, volume calculations, and cost estimate will have to be

updated at the design level prior to completing final plans and specifications.

3.10.1.3 Construction Schedule

The construction schedule for the initial restoration of the NER Plan and

recommended component of construction consists of project

mobilization/demobilization and construction access, beach/dune and marsh fill

placement, and borrow area pipeline relocation for both the NER Plan and the

recommended component of construction. The NER Plan was divided into two

separate construction contracts. The NER Plan Contract No.1 consists of the initial

restoration of Whiskey Island, Trinity Island, and Raccoon Island with terminal

groin. The NER Plan Contract No. 2 consists of initial restoration of Timbalier

Island. The islands were divided between the contracts on the basis of common

borrow area allocations and construction duration. Construction of NER Plan

Contracts No.1 and No. 2 shall begin concurrently. The estimated timeline for

construction of the NER Plan and recommended component of construction are

summarized below and described in detail in Appendix L.

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The following assumptions were made in developing the construction schedules:

 Single dredge plant would be utilized per contract

 NER Plan Contracts No.1 and No.2 would commence construction

simultaneously

 Construction Access for each subsequent island would be constructed

concurrent with the previous islands fill placement

 March Fill containment dikes would be constructed concurrent with

beach/dune fill placement

 Construction of the Terminal Groin would be done concurrent with fill

placement.

3.10.1.3.1 NER Plan Restoration Construction Schedule Contract No. 1

 Project Mobilization: 56 days

 Whiskey Island Beach/Dune Construction: 325 days

 Borrow Area Pipeline Relocation: 94 days

 Trinity Island Beach/Dune Construction: 168 days

 Borrow Area Pipeline Relocation: 63 days

 Trinity Island Marsh Construction: 193 days

 Borrow Area Pipeline Relocation: 60 days

 Whiskey Island Marsh Construction: 23 days

 Borrow Area Pipeline Relocation: 61 days

 Raccoon Island Beach/Dune: 204 days

 Raccoon Island Marsh & Terminal Groin Construction: 109 days

 Borrow Area Pipeline Relocation: 56 days

 Raccoon Island Marsh Construction: 48 days

 Demobilization: 35 days

Total construction time for initial restoration of the NER Plan Contract No. 1 is

49.2 months.

3.10.1.3.2 NER Plan Restoration Construction Schedule Contract No. 2

 Project Mobilization: 71 days

 Timbalier Island Beach/Dune Construction: 474 days

 Timbalier Island Marsh Construction: 130 days

 Borrow Area Pipeline Relocation: 112 days

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 Timbalier Island Marsh Construction: 237 days

 Borrow Area Pipeline Relocation: 81 days

 Timbalier Island Marsh Construction: 61 days

 Demobilization: 52 days

Total construction time for initial restoration of the NER Plan Contract No. 2 is

40.1 months. Contract No. 2 will run concurrently with Contract No. 1.

3.10.1.3.3 Initial Restoration Construction Schedule for the Recommended

Component of Construction

 Project Mobilization: 56 days

 Whiskey Island Beach/Dune Construction: 325 days

 Borrow Area Pipeline Relocation: 65 days

 Whiskey Island Marsh Construction: 23 days

 Demobilization: 37 days

Total construction time for the initial restoration of the recommended component of

construction is 16.6 months. Vegetative plantings and sand fencing will be

scheduled following fill activities in accordance with Appendix L.

3.10.2 Implementation Responsibilities

The non-Federal sponsor shall, prior to implementation, agree to perform all of the

local cooperation requirements and non-Federal obligations. Local cooperation

requirements and non-Federal sponsor obligations include, but are not necessarily

limited to:

 Provide a minimum of 35 percent of total project costs as further specified

below:

 Enter into an agreement which provides, prior to execution of the project

partnership agreement, 25 percent of design costs;

 Provide, during the first year of construction, any additional funds

needed to cover the non-Federal share of design costs;

 Provide all lands, easements, and rights-of-way, including those required

for relocations, the borrowing of material, and the disposal of dredged or

excavated material; perform or ensure the performance of all relocations;

and construct improvements required on lands, easements, and rights-ofway to enable the disposal of dredged or excavated material that the

Government determines to be necessary for the construction, operation,

maintenance, repair, replacement, and rehabilitation of the project;

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 Provide, during construction, any additional funds necessary to make its

total contribution equal to 35 percent of the total project costs allocated

to the project;

 Provide the non-Federal share of that portion of the costs of mitigation and

data recovery activities associated with historic preservation, that are in

excess of 1 percent of the total amount authorized to be appropriated for the

project;

 Not use funds provided by a Federal agency under any other Federal

program, to satisfy, in whole or in part, the non-Federal share of the cost of

the project unless the Federal agency that provides the funds determines that

the funds are authorized to be used to carry out the study or project;

 Not use project or lands, easements, and rights-of-way required for the

project as a wetlands bank or mitigation credit for any other project;

 For as long as the project remains authorized, operate, maintain, repair,

replace, and rehabilitate the project, or functional portions of the project,

including mitigation, at no cost to the Federal Government, in a manner

compatible with the projects authorized purposes and in accordance with

applicable Federal and state laws and regulations and any specific directions

prescribed by the Federal Government;

 Give the Federal Government a right to enter, at reasonable times and in a

reasonable manner, upon property that the non-Federal sponsor, now or

hereafter, owns or controls for access to the project for the purpose of

inspecting, operating, maintaining, repairing, replacing, rehabilitating, or

completing the project. No completion, operation, maintenance, repair,

replacement, or rehabilitation by the Federal Government shall relieve the

non-Federal sponsor of responsibility to meet the non-Federal sponsors

obligations, or to preclude the Federal Government from pursuing any other

remedy at law or equity to ensure faithful performance;

 Hold and save the United States free from all damages arising from the

construction, operation, maintenance, repair, replacement, and rehabilitation

of the project and any project-related betterments, except for damages due to

the fault or negligence of the United States or its contractors;

 Perform, or cause to be performed, any investigations for hazardous

substances that are determined necessary to identify the existence and extent

of any hazardous substances regulated under the Comprehensive

Environmental Response, Compensation, and Liability Act (CERCLA), Public

Law 96-510, as amended (42 U.S.C. 9601-9675), that may exist in, on, or

under lands, easements, or rights-of-way that the Federal Government

determines to be required for the initial construction, periodic nourishment,

operation, and maintenance of the project. However, for lands that the

Federal Government determines to be subject to the navigation servitude,

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only the Federal Government shall perform such investigations unless the

Federal Government provides the non-Federal sponsor with prior specific

written direction, in which case the non-Federal sponsor shall perform such

investigations in accordance with such written direction;

 Assume, as between the Federal Government and the non-Federal sponsor,

complete financial responsibility for all necessary cleanup and response costs

of any CERCLA regulated materials located in, on, or under lands,

easements, or rights-of-way that the Federal Government determines to be

necessary for the initial construction, periodic nourishment, operation, or

maintenance of the project;

 Agree that, as between the Federal Government and the non-Federal

sponsor, the non-Federal sponsor shall be considered the operator of the

project for the purpose of CERCLA liability, and to the maximum extent

practicable, operate, maintain, and repair the project in a manner that would

not cause liability to arise under CERCLA;

 Prevent obstructions of or encroachments on the project (including

prescribing and enforcing regulations to prevent such obstruction or

encroachments) which might reduce ecosystem restoration benefits, hinder

operation and maintenance, or interfere with the projects proper function,

such as any new developments on project lands or the addition of facilities

which would degrade the benefits of the project;

 Keep and maintain books, records, documents, and other evidence pertaining

to costs and expenses incurred pursuant to the project, for a minimum of 3

years after completion of the accounting for which such books, records,

documents, and other evidence is required, to the extent and in such detail as

would properly reflect total costs of construction of the project, and in

accordance with the standards for financial management systems set forth in

the Uniform Administrative Requirements for Grants and Cooperative

Agreements to State and Local Governments at 32 Code of Federal

Regulations (CFR) Section 33.20;

 Comply with Section 221 of Public Law 91-611, Flood Control Act of 1970, as

amended (42 U.S.C. 1962d-5), and Section 103 of the Water Resources

Development Act of 1986, Public Law 99-662, as amended (33 U.S.C. 2213),

which provides that the Secretary of the Army shall not commence the

construction of any water resources project or separable element thereof,

until the non-Federal sponsor has entered into a written agreement to

furnish its required cooperation for the project or separable element;

 Comply with all applicable Federal and state laws and regulations, including,

but not limited to, Section 601 of the Civil Rights Act of 1964, Public Law 88-

352 (42 U.S.C. 2000d), and Department of Defense Directive 5500.11 issued

pursuant thereto, as well as Army Regulation 600-7, entitled

"Nondiscrimination on the Basis of Handicap in Programs and Activities

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Assisted or Conducted by the Department of the Army, and all applicable

Federal labor standards and requirements, including but not limited to 40

U.S.C. 3141- 3148 and 40 U.S.C. 3701  3708 (revising, codifying, and

enacting without substantial change the provisions of the Davis-Bacon Act

(formerly 40 U.S.C. 276a et seq.), the Contract Work Hours and Safety

Standards Act (formerly 40 U.S.C. 327 et seq.) and the Copeland AntiKickback Act (formerly 40 U.S.C. 276c et seq.); and

 Comply with all applicable provisions of the Uniform Relocation Assistance

and Real Property Acquisition Policies Act of 1970, Public Law 91-646, as

amended (42 U.S.C. 4601-4655), and the Uniform Regulations contained in

49 CFR Part 24, in acquiring lands, easements, and rights-of-way necessary

for the initial construction, periodic nourishment, operation, and

maintenance of the project, including those necessary for relocations, borrow

materials, and dredged or excavated material disposal, and inform all

affected persons of applicable benefits, policies, and procedures in connection

with said Act.

3.10.3 Cost Sharing

The State of Louisiana, acting through the Coastal Protection and Restoration

Authority of Louisiana (CPRA), will be the non-Federal sponsor for the LCA TBBSR

Study. In November 2008, the USACE and CPRA executed a single Feasibility

Cost-Share Agreement covering six Louisiana Coastal Area near-term plan

elements listed in Section 7006(e) of the Water Resources Development Act of 2007.

The six features each underwent a separate feasibility analysis and environmental

compliance analysis culminating in a single master feasibility document. The costshare during the feasibility phase was 50% Federal and 50% non-Federal.

However, the individual elements have been divided so that each entity had lead

responsibility for preparing three of the six report components. At the end of the

feasibility phase the total cost for all elements will have been shared on a 50/50

basis, yet for work on each individual element during the feasibility phase the ratio

of funds expended by either the Federal or non-Federal sponsor will be higher

depending upon their level of responsibility. CPRA had the technical planning lead

for this particular LCA study element.

Following the feasibility phase, the cost share for the planning, design and

construction of the project will be 65% Federal and 35% non-Federal. CPRA must

provide all LERRDs required for the project. The 35% share of the project cost

includes the CPRAs responsibility for providing all LERRDs. Operation,

Maintenance, Repair, Replacement and Rehabilitation (OMRR&R) of the project

would be a 100% CPRA responsibility. The cost apportionment of the NER Plan and

recommended component of construction is presented in Tables 3-54 and 3-55.

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Under current law, authority for the non-Federal sponsor to receive credit for

construction activities is limited. Section 7007(a) of WRDA 2007 authorizes the

Secretary to credit, "toward the non-Federal share of the cost of a study or project

under this title the cost of work carried out in the coastal Louisiana ecosystem by

the non-Federal interest for the project before the date of the execution of the

partnership agreement for the study or project." In addition, section 7007(a)

incorporates the requirement of section 221 of the Flood Control Act of 1970, as

amended, (42 U.S.C. 1962d-5b) that the Government and non-Federal sponsor must

enter into a separate agreement for any work that will be carried out prior to

execution of the partnership agreement. In other words, work undertaken by the

non-Federal sponsor prior to (but not after) execution of the project partnership

agreement (PPA) is eligible for credit subject to execution of a separate agreement

covering such work before it is undertaken. For design work that the non-Federal

sponsor proposes to undertake, the Design Agreement will serve as the required

separate agreement. For construction work that the non-Federal sponsor proposes

to undertake, an In-Kind Memorandum of Understanding will be required.

Opportunities to enter into an In-Kind MOU for construction activities will depend

on the schedule for entering into the PPA for a project.

Section 7007(d) provides that credit afforded under section 7007 that is in "excess"

of the non-Federal cost share for a study or project authorized in Title VII of the

Water Resources Development Act of 2007 may be applied toward the non-Federal

cost share of any other study or project under that title. "Excess" credit will be

applied only toward another study or project involving the same sponsor. In

addition, "excess" credit will be applied within project phases (i.e., study to study,

design to design, and construction to construction). At this time, it is anticipated

that that there are limited opportunities for the application of "excess credit" from

other Title VII projects toward these projects.

Table 3-54. Cost apportionment for the NER Plan  Initial Restoration

Item Total Federal NonFederal

PED $29,000,000 $19,000,000 $10,000,000

Construction Management $29,000,000 $19,000,000 $10,000,000

Adaptive Management $5,820,000 $3,780,000 $2,040,000

Construction $582,000,000 $379,000,000 $203,000,000

LERRD $692,000 $0 $692,000

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Item Total Federal NonFederal

Total (First Costs) $647,000,000 $421,000,000 $226,000,000

Table 3-55 Cost apportionment for the Recommended Component of

Construction  Initial Restoration

Item Total Federal NonFederal

PED $4,890,000 $3,180,000 $1,710,000

Construction Management $4,890,000 $3,180,000 $1,710,000

Adaptive Management $5,820,000 $3,780,000 $2.040,000

Construction $98,000,000 $64,000,000 $34,000,000

LERRD $65,000 $0 $65,000

Total (First Costs) $4,890,000 $3,180,000 $1,710,000

3.10.4 Environmental Commitments

The USACE, its non-Federal sponsor (CPRA) and contractors commit to avoiding,

minimizing, or mitigating for adverse effects during construction activities by

taking the following actions:

1. Employ best management practices with regard to erosion and turbidity control.

Prior to construction, the construction team should examine all areas of proposed

erosion/turbidity control in the field, and make adjustments to the plan specified in

the plan control device as warranted by actual field conditions at the time of

construction.

2. The contract specifications will prohibit the contractor from dumping oil, fuel, or

hazardous wastes in the work area and will require that the contractor adopt safe

and sanitary measures for the disposal of solid wastes. The contractor will be

required to prepare a spill prevention plan.

3. Demolition debris would be transported to a landfill or otherwise disposed of in

accordance with Federal, State, and local requirements. Concrete or paving

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materials would be disposed of in accordance with Federal, State, and local

requirements.

4. Inform contractor personnel of the potential presence of threatened and

endangered species in the Study area, the need for precautionary measures and the

Endangered Species Act prohibition on taking listed species.

5. Special measures will be incorporated during project construction to minimize

effects to any listed species that may be present. These measures are presented in

the Biological Assessment (Appendix A).

6. Both the CPRA and the USFWS have been consulted for recommendations on

avoidance of impacts to federally listed and State listed species. Both the CPRA

and USFWS will be consulted in the event that colonial or solitary wading bird

nests are observed within the construction footprint.

7. The USACE agrees to maintain an open and cooperative informal consultation

process with the USFWS throughout the design, construction, and operation of this

restoration project.

8. To protect cultural resources, stipulations resulting from Section 106

consultation with the ACHP, SHPO, and Federally recognized Indian tribes will be

followed. Language will be included in construction contract specifications

outlining the steps to be taken in the event of the discovery of a previously

unidentified historic property, including archaeological sites, human remains, and

properties of traditional religious and cultural significance to Indian tribes during

the execution of the project. An informational training session, developed by a

professional archaeologist, will be conducted for the contractors personnel to

explain what kinds of archaeological/cultural materials might be encountered

during construction of the island plan, and the steps to be taken in the event these

materials are encountered. A professional archaeologist will conduct periodic

monitoring of the Study area during ground disturbing activities to determine if

activities are impacting unanticipated historic properties.

During the review process for the Integrated Feasibility Report and Final EIS a

number of issues were raised that will be addressed during the PED process. These

issues fell naturally into six groups or themes:

 Consider project design, construction phasing, project operations planning,

and adaptive management scenarios that minimize impacts to the organisms

and their habitats. Concerns are Threatened and Endangered (T&E) species,

marsh hydroperiod stability, and the need for robust modeling to support

project operations and maintenance and aggressive adaptive management

(necessity for rapid response to changing conditions);

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 Consider expansion of geotechnical, geophysical, and cultural resources data

gathering and analysis to further refine borrow areas for beach/dune and

marsh fill, and to locate additional cost effective fill sources;

 Consider expansion of geotechnical data gathering and analysis relevant to

excavation and stability of native soils/water bottoms for access channel and

containment dike construction and post-construction degradation;

 Ensure ongoing consultation and cooperation with local, State, and Federal

resource and environmental agencies to address protection and enhancement

of habitat stability, heterogeneity, and longevity, as well as life-cycle

protection for fish and wildlife, especially T&E species such as shore birds, at

both the borrow areas and the fill-placement areas;

 Due to the highly variable nature of the coastal processes within the

Terrebonne Basin and the limitations of modeling barrier island restoration

performance and response to structures with the GENESIS model, conduct

combined wave and current modeling on a system-wide level to support the

National Ecosystem Restoration Plan; and

 The feasibility level monitoring and adaptive management plan will be

revised to include consideration for expanding the monitoring plan to better

assess physical processes that govern the geomorphologic changes of the

islands. However, this detailed level of monitoring may be considered more

of a research activity than monitoring specifically aimed at determining if a

Study has achieved its objectives. Further, a more detailed description of the

scope and cost-sharing for the monitoring and adaptive management plan

will be provided.

3.10.5 Financial Requirements

It is expected that the CPRA will have the capacity to provide the required local

cooperation for the recommended component of construction. A project schedule and

cost estimate will be provided to the CPRA so that it may develop a financing plan.

A standard cost share percentage of 65% Federal and 35% non-Federal would be

applied to the total first cost of the project, including the value of PED costs

construction features.

Section 7007(b) of WRDA 2007 provides that "The non-Federal interest may use,

and the Secretary shall accept, funds provided by a Federal agency under any other

Federal program, to satisfy, in whole or part, the non-Federal share of the cost of

the study or project if the Federal agency that provides the funds determines that

the funds are authorized to carry out the study or project." If the Mineral

Management Services determines in writing that funds it provides to the nonFederal sponsor under the Energy Policy Act of 2005 (Coastal Impact Assistance

Program - CIAP) and the Gulf of Mexico Energy Security Act of 2006 (GOMESA)

are authorized to be used to carry out LCA projects, the non-Federal sponsor can

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use those funds toward satisfying its local cooperation for the project, including the

non-Federal sponsor's acquisition of Lands, Easements, Relocations, Right-of-ways

and Disposals (LERRDs) required for the project.

By letters dated July 2, 2009 and December 18, 2009, the Minerals Management

Service and the USACE established a process for the Minerals Management Service

to provide its written determination regarding the acceptability of the use of CIAP

funds for LCA studies, projects, and programs. That process provides that the

Minerals Management Services' written determination for a specific study, project,

or program will take the form of the grant award document for that activity.

3.10.6 Views of Non-Federal Sponsor

CPRA TBBSR Study and sponsoring the project construction in accordance with the

items of local cooperation that are set forth in the recommendations chapter of this

report. In addition, CPRA supports the NER Plan (Alternative 5) since this plan

restores the geomorphologic form and ecologic function of the four islands in the

Terrebonne Basin barrier system by creating a total of 4,792 acres of beach/dune

and 1,048 acres of marsh. The plan is also cost-effective and provides the most

benefits of all the Best-Buy plans in the final array. However, due to authorized

cost limitations in WRDA 2007, CPRA supports Whiskey Island Plan C as the

recommended component of construction. CPRA believes the project warrants

additional Congressional authorization to increase funding and allow the

implementation of the NER Plan (Alternative 5) to fully address the barrier island

needs identified in this report.

The State of Louisiana fully supports the project. The State recognizes that the

USACE's position is that section 7007 does not authorize credit for work carried out

after the date of a partnership agreement. However, the state disagrees with the

USACE position and intends to continue to seek a change in law that would allow

in-kind contribution credit for work carried out after the date of a Project

Partnership Agreement and that would allow for such in-kind contributions credit

to carry over between LCA Program components (i.e., excess credit for work

undertaken after signing of the project partnership agreement for one project may

be carried over for credit to another project). Nevertheless, while the State is of the

opinion that its view is consistent with the authority and Congressional intent

under WRDA 2007, the state fully intends to proceed with the project under the

Corps interpretation of current law and to meet all non-Federal financial and other

obligations outlined by the USACE in this report until such time as the law is

changed.

The States letter of support is provided as attachement one of this report.

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4.0 AFFECTED ENVIRONMENT

This chapter describes the climate, geomorphic and physiographic setting, and the

historic and existing conditions for the following significant resources: soils; coastal

vegetation; wildlife; fisheries; plankton; benthos; essential fish habitat (EFH);

threatened and endangered species; coastal processes and hydrology; salinity

regimes; water quality; recreation; cultural resources; aesthetics; air quality;

socioeconomic and human resources (including population; infrastructure;

employment and income; navigation; oil, gas, and utilities; pipelines; commercial

fisheries; oyster leases; and flood control and hurricane protection). In addition, the

characterization of noise and hazardous, toxic, and radioactive waste (HTRW) in the

Study Area are presented.

A resource is considered important if it is recognized by statutory authorities

including laws, regulations, Executive Orders (EO), policies, rules, or guidance; if it

is recognized as important by some segment of the general public; or if it is

determined to be important based on technical or scientific criteria. The following

sections discuss historic and existing conditions of each important resource

occurring within the Study Area. The final programmatic environmental impact

statement (EIS) for the Louisiana Coastal Area (LCA) Ecosystem Restoration Study

(USACE 2004) presents detailed information relevant to this current study.

Consistent with 40 CFR Part 1502.21, that information is incorporated by reference.

The Terrebonne Basin, similar to the rest of coastal Louisiana, including its

wetlands, lakes, bays, and barrier shorelines, was produced by the deltaic processes

of the Mississippi River in the east and Gulf and Riverine processes in the west.

The Terrebonne Basin contains an extraordinary diversity of coastal habitats that

range from natural levees and beach ridges to forested swamps, freshwater,

intermediate, brackish and saline marshes, freshwater lakes, and bays of variable

salinity. These landforms, along with their related hydrologic and biological

processes, provide unique habitats that are crucial to the viability of migratory

birds, commercial and recreational fisheries, and a great variety of terrestrial and

aquatic species. Coastal wetlands also contribute to water quality in the region by

reducing suspended sediment and nutrient loading in the aquatic environment. In

human terms, these coastal wetlands have been a center for culturally diverse

social development recognized and appreciated worldwide. In addition, coastal

landforms and wetlands reduce the impact of flooding and storm surges on

infrastructure in the coastal region, including highways, oil and gas production

facilities, pipelines, and navigation features, such as ports and channels (USACE,

2008).

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4.1 ENVIRONMENTAL SETTING OF STUDY AREA

4.1.1 Location

The Study, located in LCA Subprovince 3, provides for the restoration of the

Timbalier and Isles Dernieres Barrier Island reaches located in Terrebonne and

Lafourche Parishes, Louisiana. The Study Area (Figure 1-1) is located in the 3rd

Congressional District. The Study Area consists of the barrier islands being

considered for restoration as well as Ship Shoal.

Isles Dernieres Reach

The Isles Dernieres Reach represents a barrier island arc approximately 22 miles

long in the southern reaches of Terrebonne Parish and extends from Caillou Bay

east to Cat Island Pass. Raccoon, Whiskey, Trinity, East, and Wine, the primary

islands that comprise the Isles Dernieres barrier island reach, are backed by Bay

Blanc, Bay Round, Caillou Bay and Terrebonne Bay, and bordered by the Gulf of

Mexico (GOM) on the seaward side. The remnant of Wine Island is located in Wine

Island Pass, about midway between East and Timbalier Islands. The islands of the

Isles Dernieres Reach range from approximately 0.1 to 0.85 miles wide and are

typically composed of a thin sand cap over a thick mud platform. Elevations are

generally low and the islands are frequently overwashed (USACE, 2004c).

For more than a century, the Isles Dernieres have experienced significant and

persistent degradation and fragmentation. The average long-term (18872002) rate

of shoreline change for the Isles Dernieres was -34.7 ft/yr with a range of -56.0/-17.0

ft/yr. The average short-term (19882002) rate of shoreline change was -61.9 ft/yr

with a range of -60.5/-38.6 ft/yr (USACE, 2004c).

For more than 150 years, the Isles Dernieres has been an important commercial

and recreational resource for Louisiana and the nation. The primary commercial

activities in the area, oil and gas mineral extraction and fisheries harvesting, are

interwoven inshore and offshore of the islands. As well, the islands have

historically played an important role in coastal Louisiana recreation. The Isles

Dernieres contained the first major coastal resort in Louisiana (later washed away

by the great hurricane of 1856), and continues to provide premier hunting and

fishing recreation for both State residents and non-residents alike (USACE, 2004c).

Timbalier Reach

The Timbalier Reach is comprised of Timbalier Island and East Timbalier Island.

Timbalier and East Timbalier Islands are on the western edge of the Lafourche

barrier shoreline and are located about 60 miles southwest of New Orleans,

Louisiana. This barrier island shoreline is approximately 20 miles long and backed

by Terrebonne and Timbalier Bay to the north and delimited by Raccoon Pass to the

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east and Cat Island Pass to the west. The islands range from 0.1 to 0.6 miles wide,

with low elevations. Though onshore and offshore oil and gas development and

production facilities are supported by both Timbalier and East Timbalier Islands,

those facilities are prevalent on and around the East Timbalier but are few and

scattered along Timbalier Island. Oil and gas canals are present on both islands

(USACE, 2004c).

Ship Shoal

Ship Shoal is the largest and easternmost of a series of sand shoals on the inner

continental shelf of Louisiana and contains approximately 1.6 billion cy of fine sand

(Stone et al. 2009). The elongated shoal lies parallel to the coast approximately 8 to

12 miles (12 to 19 km) south of the Isles Dernieres Reach and measures

approximately 31 miles (50 km) in an east-west direction (Khalil et al. 2007). The

potential borrow areas identified within the shoal include Ship Shoal MMS Lease

Blocks 87, 88, 89, 94, and 95 South Pelto Blocks 12, 13, 14, 18, and 19.

4.1.2 Climate

Climate is one of the major factors necessitating implementation of the proposed

action. The climate of coastal Louisiana is one that is significantly influenced by

the Gulf of Mexico (GOM) water and wind systems. These maritime conditions give

rise to a humid subtropical climate, with long, hot, humid summers, and mild,

abbreviated winters (USACE, 2004b). Summers are hot and humid, with

temperatures averaging approximately 81.0°F. Winters are typically mild, with

average temperatures of approximately 52.0°F, however short periods of colder

temperatures may be induced by dry continental arctic air. The daily averages for

coastal Louisiana are 78.4°F, and 58.8°F for the maximum and minimum

temperatures respectively. The climate in the Study Area provides an extended

frost-free period (264 day per year average), resulting in an average growing season

of 317 days per year (USDA, 2005).

The maritime tropical air masses typically move inland and mix with continental

air masses, producing abundant rainfall, impeding winter air masses, and reducing

extreme inland temperatures. Wind records indicate that, annually, average wind

speed in coastal Louisiana is approximately 9.8 ft per second from the southeast

(USACE, 2004b). Localized rain events, which consist of severe summer storms, and

sporadic, high-energy winter disturbances, are typically controlled by these offshore

unstable air masses and winds. The average rainfall in the coastal zone of

Louisiana is approximately 54 inches a year. Though rain events occur frequently

(approximately 74 days each year), and are fairly well distributed throughout the

year, storm frequencies are slightly elevated during the summer (July typically

contains the highest storm frequency), and are typically least severe, and least

frequent in October (USDC, 1998). Compounding the effects of severe wind and rain

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events, are the low topography that is common along the coastal marsh and barrier

islands.

Louisiana is susceptible to tropical waves, tropical depressions, tropical storms, and

hurricanes due to its proximity to the Gulf of Mexico. Historical data from 1899 to

2007 indicate that 30 hurricanes and 41 tropical storms have made landfall along

the Louisiana coastline (National Weather Service,

http://www.srh.noaa.gov/lch/research/tropical5.php and National Hurricane Center,

http://www.nhc.noaa.gov). The total amount of marsh lost as a result of Hurricanes

Katrina and Rita was over one third of the total predicted wetland losses that was

predicted by the Coast 2050 Report (LCWCRTF and WCRA, 1999).

Preliminary information on land area changes that occurred shortly after

Hurricanes Katrina and Rita, serve as a regional baseline for monitoring wetland

recovery following the 2005 hurricane season. Estimation of permanent losses

cannot be made until several growing seasons have passed and the transitory

impacts of the hurricanes are minimized, but this preliminary analysis indicates an

approximate 217-mi2 (562.03-km2) decrease in land/increase in water across coastal

Louisiana. (Barras, John A. 2006).

The Gulf Coast region is affected by tropical and extra-tropical storms. Tropical

storm events can directly and indirectly contribute to coastal land loss through a

variety of ways: 1) erosion from increased wave energies; 2) removal and/or scouring

of vegetation from storm surges; and 3) saltwater intrusion into interior wetlands

carried by storm surges. These destructive processes can result in the loss and

degradation of large areas of coastal habitats in a relatively short period of time

(days and weeks versus years). Since 1893, over 130 tropical storms and hurricanes

have struck or indirectly impacted Louisianas coastline. On average, a tropical

storm or hurricane affects Louisiana every 1.2 years. During the past 100 years,

over 50 hurricanes and tropical storms have made landfall along the Louisiana

coast with the highest incidence occurring in September.

The National Data Buoy Center, part of the National Oceanic and Atmospheric

Administration (NOAA), provides a climatic summary (Table 4-1) from December

1984 to November 2001 for station GDIL1 at Grand Isle, Louisiana, which is east of

the Terrebonne Basin. Climate in the Study Area is semitropical, primarily

influenced by the Gulf of Mexico and largely determined by 2 pressure ridges.

Though the fair weather conditions between the Study Area and Louisiana coastal

zone are comparable, the direct and indirect impacts that unique climate conditions

have on the barrier islands and coastal marshes are more detrimental.

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Table 4-1 Climate statistics

Minimum Mean Maximum

Air Temperature 14.2oF 70.3 oF 93.7 oF

Sea Temperature 28.6 oF 72.9 oF 95.0 oF

Air Pressure 29.1 in 30.0 in 30.8 in

Wind Speed 0.0 mph 11.2 mph 61.1 mph

Wind Direction, Summer NA 44% SE NA

Wind Direction, Winter NA 38% N NA

Rainfall NA 65 in NA

Source: http://seaboard.ndbc.noaa.gov/data/climatic/GDIL1.pdf

4.1.3 Geomorphic and Physiographic Setting

The geomorphic and physiographic setting is institutionally significant because of

the National Environmental Policy Act (NEPA) of 1969. Geomorphic and

physiographic conditions are technically significant because they can place

constraints on the nature, design, or location of the proposed action, as well as

determine the impacts, which the proposed action will have on other resources.

Geomorphic and physiographic conditions are publicly significant because bedrock

may be too hard for excavation or too weak to support proposed structures; mineral

deposits may be destroyed or occluded by development of the proposed action; the

existence of active faults or other hazardous geomorphic structures may

compromise the proposed action.

The following geomorphic and physiographic setting information is incorporated by

reference from the LCA FPEIS (per NEPA Section 1502.21; USACE, 2004b).

The Study Area is comprised of a chain of barrier islands and headlands, separated

by tidal inlets, which enclose shallow bays. The most prominent physiographic

features are the numerous narrow beaches and their associated dunes, overwash

fans, spits, tidal inlets, marshes, and bays. Elevations range from a maximum of

approximately 5 ft NAVD 88 on the highest dunes to near 0 ft NAVD 88 in the back

barrier marshes. All of the island segments are retreating. Erosion, reworking, and

redistribution of the coarser deltaic material led to the development of the barrier

island chain present today. Much of the erosion and transport of material takes

place during storms (frontal passages and tropical storms/hurricanes).

Geologic History:

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Since the Late Jurassic geologic time, a sedimentary succession in excess of 6 miles

thick, deposited in fluvial, deltaic, and marine environments, has accumulated. The

northern margin of the Gulf basin continues to be the site of major deltaic

deposition. Today, the basin receives approximately 6.1 million tons of sediment

annually from North Americas largest drainage basin of more than 1.2 million

square miles (mi2). The trunk distributary of this drainage system is the Mississippi

River. During the Holocene, the river constructed the Mississippi River Deltaic

Plain, one of the worlds largest delta plains in excess of 11,500 mi2. The Deltaic

Plain consists of a generally fine-grained sedimentary package deposited within a

wide variety of fluvial, deltaic, and coastal depositional environments (USACE,

2004c).

Deltaic Cycle:

The geologic development of coastal Louisiana and the resulting coastal landscape

were dependent upon shifting Mississippi River courses and are influenced by the

orderly progression of events related to the "deltaic cycle." The deltaic cycle is a

dynamic and episodic process alternating between periods of delta-building with

seaward advancement (progradation) of deltas and the subsequent landward retreat

(degradation). As deltas are abandoned, the seaward edges are reworked into

barrier headlands and barrier islands. Subsequently, the wetland complex behind

the headlands and islands, without a significant and continuous source of sediment

and nutrients, eventually succumbs to subsidence and becomes submerged by

marine waters. The Mississippi River has changed its course several times during

the last 7,000 years. Each time the Mississippi River has built a major delta it has

eventually abandoned that river course in favor of a shorter, more direct route to

the GOM.

The Deltaic Plain is composed of six major delta complexes: two prograding and four

degrading (Figure 4-1). The Atchafalaya and Modern Delta complexes are active

and the Teche, Lafourche, and St. Bernard complexes are inactive. Present day

Terrebonne Basin is the result of the Lafourche delta formation, through seaward

advancement from deposition of Mississippi River distributary sediment, the

subsequent delta degradation and detachment, and the reworking of seaward

headlands to form barrier islands (USACE, 2004a).

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Figure 4-1. Mississippi River deltaic plain (Kulp et al., 2005)

Delta Advancement:

The Mississippi River Deltaic Plain wetland ecosystem developed as a result of

delta-building processes, during which sea-level conditions were relatively stable.

The deltaic cycle is initiated when the Mississippi River, enters an open water body,

such as a coastal lake or bay, which slows the velocity of the Rivers flow, thus

limiting the Rivers ability to transport sediment. Consequently, most of the largergrained sediment carried by the River drops out of the water column and falls to the

bottom. Over time, the River deposits enough sediment to create land, which then

becomes colonized by wetland plants. The organic deposition from additional Riverborne sediment and decomposing wetland vegetation are the primary factors behind

the land-building process. In this fashion, large expanses of wetlands, or deltas,

form and extend seaward between the distributaries, or "fingers" of the delta, as

long as the River continues to supply freshwater, nutrients, and land-building

sediment (USACE, 2004a).

Delta Abandonment:

As a delta grows and extends into the GOM, the River stage gradually heightens.

Eventually, the River breaks through a weak point in its bank and/or shifts its main

water flow into a distributary, thus providing a shorter route for the River to travel

to the Gulf. About every 1,000 years, the Mississippi River had altered its path to

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the Gulf, sometimes flowing down the western portion of the current Deltaic Plain

and sometimes down the eastern portion. Whenever the River changed course, the

location of active delta building also changed. Areas that no longer received

sufficient volumes of freshwater laden with sediment and nutrients began to

succumb to subsidence, while those areas that received the majority of River water

input began a new phase of delta building. These meandering changes in the course

of the Mississippi River and accompanying shifts in centers of sediment deposition

are responsible for the distribution of deltaic sediment along the entire Louisiana

coast and into Texas.

Once the Mississippi River had altered its course and began to form a new delta,

tidal influences and a lack of sediment and nutrient inputs had slowly degraded the

previously active delta location. Over time, the interior wetlands were submerged

and marine influences reworked the gulfward edge of the delta into a series of

barrier headlands. As the shoreline along the GOM matured, and as the marshes

behind the shoreline broke up and eventually disappeared, the barrier headlands

transitioned into barrier islands.

Figure 4-2 presents the three-stage geomorphic model that summarizes the genesis

and evolution of transgressive depositional systems in the Mississippi River Deltaic

Plain (USACE, 2004a).

Figure 4-2. Three-stage geomorphic model.

As the marsh degraded further, open bays formed behind the barrier islands.

Eventually, complete submergence and marine reworking of the islands created

sand-rich marine shoals detached from the coastline, such as today's Ship Shoal,

which is located on the mid-central Louisiana coastal shelf.

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Delta development and degradation occurred simultaneously, with some portions of

the Louisiana coast experiencing land gain, while other areas experienced land loss.

However, the net effect of this process was the creation of land across the Deltaic

Plain. The dynamic nature of these geologic and hydrologic processes provided for

an extremely diverse and highly productive wetland ecosystem in the coastal area

(USACE, 2004a).

Thus, Louisianas barrier islands are the product of Mississippi River channel

switching over the last 5,000 years. Each time the river relocated, the delta became

subject to deteriorative forces. The barrier islands are the furthest gulfward

expression of those deltas and the barrier islands consist of the most resistant river

deposited materials. For barrier shorelines, complex interactions between storm

events, longshore sediment supply, coastal structures, and inlet dynamics

contribute to the erosion and migration of beaches, islands, and chenieres (beach

ridges) (USACE, 2004a).

Subsidence:

Land elevations decrease due to subsidence from compaction and consolidation of

sediments, faulting, groundwater depletion, and sub-surface fluid extraction. Land

elevations increase due to sediment accretion from riverine and littoral sources and

organic deposition from vegetation. Vertical accretion in the majority of the Study

Area is insufficient to offset subsidence, decreasing land elevations. Based on

NOAAs (http://tidesandcurrents.noaa.gov) current mean sea-level (MSL) trend at

Grand Isle, LA of 9.24 mm/yr and global MSL rise of 1.7 mm/yr (USACE, 2009b),

the subsidence rate in the LCA TBBSR Study Area is estimated at 7.54 mm/yr.

Topography:

Isle Dernieres Reach

The Isles Dernieres barrier island reach stretches for over 15 miles along the

Louisiana coast, approximately 63 miles west of the mouth of the modern

Mississippi River and about 75 miles southwest of New Orleans, Louisiana (Figure

1-1). The present configuration of this island reach includes the following islands,

from west to east: Raccoon Island, Whiskey Island, Trinity Island, and East Island,

along with the remnants of Wine Island. The islands are separated by the following

passes: Coupe Collin, Whiskey Pass, Coupe Juan, and Wine Island Pass.

The average long-term (18872002) rate of shoreline change for the Isles Dernieres

was -34.7 ft/yr with a range of -56.0 to -17.0 ft/yr. The average short-term (1988

2002) rate of shoreline change was -61.9 ft/yr with a range of -86.0 to -38.6 ft/yr

(USACE, 2004c). Table 4-2 presents a summary of acreage and erosion rates for all

of the islands in the Isles Dernieres Reach. Shoreline change for the Isles Dernieres

is graphically presented in Figure 4-3.

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Table 4-2. Summary of Acreage and Erosion Rates for the Isles Dernieres

(Barras, 2009; USACE, 2004c)

Island Acreage in

2008

Short-term

Erosion

Rate (ft/yr)

Longterm

Erosion

Rate

(ft/yr)

Historic

Erosion

Rate

(ft/yr)

Raccoon Island 121 -60.5 -28.6 -27.4

Whiskey Island 509 -86.0 -42.7 -56.0

Trinity Island 630 -62.5 -39.7 -38.4

East Island 300 -38.6 -39.7 -17.0

Wine Island 12 N/A -21.6 N/A

N/A denotes data not available

Figure 4-3. Short-term and Long-term Shoreline Change for the Isles

Dernieres (USACE, 2004c)

Raccoon Island

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Raccoon Island is approximately 2.6 miles long (USDA, 2007b) and is located at the

western end of Isles Dernieres. It is the largest shorebird rookery in the Isles

Dernieres. Raccoon Island is characterized by sandy beach with well-vegetated

washover terraces backed by thick groves of black mangrove and salt marsh. The

recurved spit at the west end is low and dominated by washover flats. The average

historic shoreline change rate between 1887 and 2002 was -27.4 ft/yr with a range of

-28.9 to -24.9 ft/yr. The average short-term shoreline rate was -60.5 ft/yr with a

range of -144.5 to -8.6 ft/yr between 1988 and 2002. It is noted the average shoreline

change rate increased over time, specifically from -27.4 ft/yr to -60.5 ft/yr during the

two time periods, 1887 to 2002 and 1988 to 2002, respectively (USACE, 2004c). The

average long-term shoreline change rate between 1956 and 1988 developed from the

atlas of shoreline changes on Louisiana (William et al., 1992) was -28.6 ft/yr.

Since 1978, Raccoon Island rapidly decreased in area from 368.2 to 200.2 acres

between 1978 and 1988. During this time period, multiple hurricane impacts

occurred in 1979 (Bob and Claudette) and 1985 (Danny, Elena, and Juan). From

1988 to 1992, Raccoon Island further decreased in area from 200.2 acres to 167.8

acres. With the impact of 1992s Hurricane Andrew, the area of Raccoon Island

continued to decrease even further to 112.8 acres. By 1993, Raccoon Island had

further reduced in area to 99.2 acres. The FEMA restoration project of 1994

increased the size of Raccoon Island to 127.2 acres by 1996. The CWPPRA TE-29

segmented breakwater project further increased the area of Raccoon Island to 145.5

acres by 2002. While the hurricane impacts in 2005 (Katrina and Rita) caused

erosion, the breakwaters continued to benefit the island (USACE, 2004c). Though

an increase in acreage was observed in 2006 (215 acres), the effects of Hurricanes

Gustav and Ike reduced Raccoon Island to 121 acres by the winter of 2008 (Barras,

2009).

Whiskey Island

Whiskey Island is located near the middle of five islands in the Isles Dernieres

barrier island reach. It is approximately 4.6 miles long (USDA, 2007b) and located

approximately 17.5 miles southwest from Cocodrie, Louisiana in Terrebonne Parish.

The average historic shoreline change rate between 1887 and 2002 was -56.0 ft/yr

with a range of -77.5 to -45.7 ft/yr. The average short-term shoreline change rate

was -86.0 ft between 1988 and 2002 with a range of -139.4 to -48.4 ft/yr (USACE,

2004c). The average long-term shoreline change rate between 1956 and 1988

developed from the atlas of shoreline changes on Louisiana (William et al., 1992)

was -42.7 ft/yr.

Prior to restoration, the morphology of Whiskey Island was dominated by washover

flats and isolated washover terraces. The CWPRRA restoration project (TE-27) at

Whiskey Island created an artificial dune +4 to +6 ft in elevation, which was 2 to 3

ft above the natural pre-restoration surface. As seen throughout the Isles Dernieres,

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Whiskey Island is historically erosional and decreasing in area. Between 1978 and

1988, Whiskey Island decreased in area from 904.4 acres to 564.2 acres. The

hurricanes of 1979 and 1985 were contributing factors to the decrease in area. By

1992, Whiskey Island had decreased to 505.6 acres. During the 1992 hurricane

season, Hurricane Andrew impacted this area dramatically, reducing Whiskey

Island to 440.8 acres. By 1993 it had further decreased in area to 428.4 acres. Post

storm recovery processes increased the area of Whiskey Island to 474.8 acres by

1996. Construction of the Whiskey Island project (TE-27) began in February 1998

and was completed in August 1998. By 2002, the area of Whiskey Island had

increased to 642.8 acres, a 36% increase in area. While the hurricanes in 2005

impacted the island, overwash processes and longshore sediment transport from

Trinity and East Islands benefited Whiskey Island (USACE, 2004c). The effects of

Hurricanes Gustav and Ike decreased the area of Whiskey Island to 509 acres by

the winter of 2008 (Barras, 2009).

Trinity Island

Trinity Island, the largest island of the Isles Dernieres, is approximately 5.2 miles

long (USDA, 2007b) and lies immediately to the east of Whiskey Island. The

morphology includes low dune terraces, with isolated dunes of up to 3 to 4 ft in

elevation. Overwash is more frequent at the west and east ends of the island where

elevations decrease. It is a remnant of the original mainland marsh and wellvegetated by black mangroves and salt marsh species. Trinity Island is historically

eroding. Between 1978 and 1988, Trinity Island decreased in area from 1,317.1

acres to 894.6 acres. This was a time period of multiple hurricanes in occurring in

1979 and 1985. By 1992, Trinity Island further decreased to 796.5 acres. During the

1992 hurricane season, Hurricane Andrew impacted this area, reducing Trinity

Island to 678.5 acres and by 1993, the island decreased further to 651.4 acres. By

1996, the area of Trinity Island continued to decrease to 617.4 acres. Trinity Island

increased in area from 617.4 to 710.1 in 2002 as a result of a restoration project

constructed on the western end of the islands (USACE, 2004c). Though the impacts

of Hurricanes Katrina and Rita were offset by the New Cut Project in 2006

(increasing Trinity Island to 764 acres), the effects of Hurricanes Gustav and Ike

decreased the total area of the island to 509 acres by 2008 (Barras, 2009).

The average historic shoreline change rate between 1887 and 2002 was -38.4 ft/yr

with a range of -47.9 to -34.3 ft/yr. The 1988 to 2002 average short-term change rate

was -62.5 ft/yr with a range of -107.3 to -41.1 ft/yr. The acceleration between the

long-term and short-term shoreline change rates is linked to the major hurricane

impacts of 1992 and 2002 (USACE, 2004c). The average long-term shoreline change

rate between 1956 and 1988 developed from the atlas of shoreline changes on

Louisiana (William et al., 1992) was -39.7 ft/yr.

East Island

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East Island is approximately 3.1 miles long (USDA, 2007b) and is the easternmost

island of the Isles Dernieres. It is characterized by low dunes and washover

terraces, with elevations ranging from +3 to +5 North American Vertical Datum

1988 (NAVD 88). Prior to restoration, East Island was rapidly eroding and

decreasing in area since 1887. In 1978, East Island was 368.2 acres in area and by

1988 it had decreased in size to 202.2 acres. The average historic shoreline change

between 1887 and 2002 was -17.0 ft/yr with a range of -34.6 to -5.1 ft/yr. Short-term,

between 1988 and 2002, the average shoreline erosion rates accelerated to -38.6

ft/yr with a range of -64.0 to -14.0 ft/yr. During this period of time multiple

hurricane impacts occurred in 1979 and in 1985. The 1985 impacts prompted island

restoration efforts by way of the Terrebonne Parish Barrier Island Restoration

Project (USACE, 2004c). The average long-term shoreline change rate between 1956

and 1988 developed from the atlas of shoreline changes on Louisiana (William et al.,

1992) was -39.7 ft/yr.

The East Island portion of this Study, which measured 3,200 ft long, 1,000 ft wide,

and encompassed 38 acres, used sediment from the margins of Wine Island Pass to

build foredunes to an average elevation of eight ft, and raised back barrier

elevations by an average of 3.5 ft. Subsequent to sediment settling and leaching,

vegetative planting was performed for island stability (Penland and Suter, 1988).

By 1992, East Island had continued to lose land and measured 173.4 acres in size.

After Hurricane Andrew made landfall in 1992, East Island was further reduced to

93.4 acres, and this continued into 1993 when East Island reached 88.5 acres in

size. Following Hurricane Andrew, FEMA did an emergency restoration project east

of the former Terrebonne Parish restoration site, resulting in East Island enlarging

from 88.5 acres in 1993 to 193.1 acres in 1996. The CWPPRA East Island

restoration was completed in 1998, and the area of the island increased from 193.1

acres to 380.4 acres by 2002 (USACE, 2004c). By 2008 East Island decreased to

approximately 300 acres due to the hurricane impacts in 2005 and 2008.

Wine Island

Wine Island, located approximately 2.5 miles northeast of East Island and 3.9 miles

west of Timbalier Island, lies on Wine Island Shoal, with Wine Island Pass to the

west and Cat Island Pass to the east. Historically, Wine Island was the

easternmost of the Isles Dernieres. It was approximately three miles in length, and

located across the mouth of the present Wine Island/Cat Island Pass (Penland, et

al., 2005). By the mid-20th Century the island had migrated north and eroded

away. What is now called Wine Island is a dredge spoil disposal site, associated

with the Houma Navigation Canal (HNC). In 1991 the present configuration was

created when the South Terrebonne Tidewater Management and Conservation

District (District) constructed the rock containment dike and the USACE filled it

with dredge spoil from the HNC. The original restoration created a 24-acre island,

approximately 1,500 ft, east to west. The island was vegetated with a mixture of

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cordgrass, black mangrove, and ryegrass by the District and the Coastal

Restoration Division of the Louisiana Department of Natural Resources in the same

year. In 1992 Hurricane Andrew overwashed the island, decimated the vegetation,

and washed approximately one-third of the land away. Plans for additional rock

structures, dredge spoil placement, and vegetation planting never materialized and

responsibility for the island was transferred to the Louisiana Department of

Wildlife and Fisheries.

The present island is small; approximately 800 ft in east-west dimension. The

island is no longer contained within the revetment: its area has been reduced

significantly and its footprint has migrated north such that about one third of it

presently lies outside the subcircular ring of rocks. Whether the present land mass

has been supplemented by subsequent dredge spoil disposal is unknown. Its low

relief and sparse vegetation point to periodic overwash, as does its ongoing

migration out of the encircling rock revetment. The average long-term shoreline

change rate between 1956 and 1988 developed from the atlas of shoreline changes

on Louisiana (William et al., 1992) was -21.6 ft/yr.

The island is a thriving bird rookery. There is strong public sentiment, from

Terrebonne Parish residents and Parish government, to protect and expand Wine

Island.

Timbalier Reach

The Timbalier Islands are very dynamic island systems that form the eastern end of

the Study Area and are migrating both landward and laterally. The Timbalier

Islands are comprised of the Western and Eastern section of Timbalier and East

Timbalier Island. Over the last century, Timbalier Island lost most of its area,

shrinking from 3,580 acres to 1,349 acres; most of the loss occurred on the bayside.

From 1978 to 1988, the island lost an average of 63 acres/yr as result of opposite

rates of migration of Gulf and bayside shorelines, that is, the bayside shoreline

migrated seaward while the Gulf shoreline migrated landward.

The average historic rates of shoreline change for the Timbalier Islands was -36.1

ft/yr with a range of -61.2 to -4.1 ft/yr between 1887 and 2002. The average shortterm rate of shoreline change was -76.4 ft/yr with a range of -179.4 to -13.4 ft/yr

between 1988 and 2002 (USACE, 2004c). Table 4-3 presents a summary of acreage

and erosion rates for Timbalier and East Timbalier Islands. Shoreline change for

the Timbalier Reach is graphically presented in Figure 4-4.

Historically, the Timbalier Islands have undergone large negative and positive area

rate changes. Between 1887 and 1934 the area of the Timbalier Islands decreased

from 4,142 acres to 2,875 acres at a rate of 27.0 acres/yr. Between the next two

periods, 1934 to 1955 and 1956 to 1978, the Timbalier Islands increased from 2,875

acres to 3,280 acres to 3,693 acres at a rate of +18.8 acres/yr respectively. This was

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a period of extensive back-barrier canal dredging and dredge spoil placement to

support oil and gas development that inadvertently increased the areas of the

Timbalier Islands. The large decrease in the area between 1978 and 1988 is a

function of the extension of the Belle Pass jetties to the east and the disruption of

the dominant longshore sediment transport to the west (USACE, 2004c). The

combination of a diminishing sediment supply and hurricanes continued to drive

island barrier loss, reducing the Timbalier Islands to 1,354 acres by 2008.

Table 4-3. Summary of Acreage and Erosion Rates for the Timbalier Reach

(Barras, 2009; USACE, 2004c)

Island Acreage in

2008

Short-term

Erosion Rate

(ft/yr)

Long-term

Erosion Rate

(ft/yr)

Historic

Erosion Rate

(ft/yr)

Timbalier Island 1,112 -96.4* -32.5 -23.5*

East Timbalier Island 242 -36.3 -21.4 -61.2

*Averaged erosion rates for Western and Eastern sections of Timbalier Island

Figure 4-4. Short-term and Long-term Shoreline Change for the Timbalier

Reach (USACE, 2004c)

Timbalier Island

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Timbalier Island is approximately 7 miles long (USDA, 2007b) and lies in

Terrebonne and Lafourche Parishes. Historical maps of shoreline change have

provided insight into the erosion process during the rapid westward migration by

Timbalier Island. Over the last 115 years, Timbalier Island has migrated 2.5 miles

to the west by the erosion of its east end and the recurve spit extension of its west

end. With this westward migration, Timbalier Island has developed two distinct

shoreline change rate regimes (USACE, 2004c).

The average historic rate of shoreline change for the eastern portion of Timbalier

Island was -42.9 ft/yr between 1887 and 2002 with a range of -48.6 to -37.3 ft/yr.

Between 1988 and 2002, the average short-term erosion rate accelerated to -179.4

ft/yr with a range of -205.5 to -153.3 ft/yr for the eastern portion. The high rates of

negative change reflect the impact of the 1992 and 2002 hurricanes. Conversely,

with the western migration of Timbalier Island, the western portion of the island

has historically shown a lower rate of shoreline change. The average historic erosion

rate for the western portion is -4.1 ft/yr with a range of -31.0 to +20.9 ft/yr between

1887 and 2002. The western portion has experienced an average short-term erosion

rate between 1988 and 2002 of 13.4 ft/yr with a range of -118.7 to +31.9 ft/yr. The

combination of the 1985/1992/2002 hurricanes and disruption of the westward

sediment transport by the Belle Pass jetties have all contributed to the high rates of

shoreline change in this area (USACE, 2004c). The average long-term shoreline

change rate between 1956 and 1988 developed from the atlas of shoreline changes

on Louisiana (William et al., 1992) was -32.5 ft/yr.

East Timbalier Island

East Timbalier Island is approximately 3.6 miles long (USDA, 2007b) and lies east

of Little Pass Timbalier and directly west of the Bayou Lafourche headland. East

Timbalier Island is occupied by a major oil and gas operation at the inshore

Timbalier Bay Field. The island and surrounding bay supports major offshore

production facilities. East Timbalier Island is known for the massive rip-rap seawall

along its Gulf shoreline and numerous revetments landward of it. The combination

of the position of East Timbalier Island immediately downdrift of the Bayou

Lafourche headland and the Belle Pass jetties create one of the most erosional areas

in coastal Louisiana (USACE, 2004c).

The average historic erosion rate between 1887 and 2002 was -61.2 ft/yr with a

range of -74.3 to -49.2 ft/yr. The average short-term erosion rate between 1988 and

2002 decreased to -36.3 ft/yr with a range of -65.5 to -4.9 ft/yr. The erosion rate

diminished here in spite of the 1992 and 2002 hurricanes. This shoreline erosion

decrease is partially related to the construction of CWPPRA restoration project TE25/30 in 2000, which created approximately 109 acres of new land (USACE, 2004c).

The average long-term shoreline change rate between 1956 and 1988 developed

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from the atlas of shoreline changes on Louisiana (William et al., 1992) was -21.4

ft/yr.

4.2 SIGNIFICANT RESOURCES

4.2.1 Soils and Water bottoms

4.2.1.1 Soils

The deltaic and chenier plains of coastal Louisiana consist of soils that can be

divided into six primary associations. These soils are primarily mineral deltaic, or

mineral coastal deposits formed from alluvial or aeolian processes. The soils that

exist nearest to the coast may also be formed or deposited by marine processes and

sediments. The six coastal associations often contain soils with organic matter in

the upper horizon, or throughout the whole profile (USACE, 2004b).

Soils in the Study Area are characterized by the depositional environments

associated with the deltaic cycle. These soils are formed or deposited by marine

processes and sediment (USACE, 2004b). The seaward edges of these islands are

typically linear or curvilinear forms consisting of loamy fine sand (fluid mineral

soils) formed by means of marine reworking. The back-barrier saltwater marshes

consist of level, very poorly drained soils that have a mucky surface layer (high

levels of organic matter), and a mucky or clayey underlying material (USDA,

2007a).

Specific geotechnical investigations including test borings were conducted on the

islands as part of the CWPPRA project designs. For Whiskey Island, auger borings

taken on the beach and dune revealed fine sand with shell fragments while the

back-bay and marsh borings indicated soft clays and silty clays with lenses of sand,

silt and shell comprised the upper 65 ft, and were underlain by medium stiff prodelta clays with silt and sand lenses (LDNR, 2007). On Raccoon Island, the results

of the test borings indicated that generally the soils are loose sands underlain by

weak compressible clays to depths of over 100 ft. The upper 12 to 15 ft was

classified as fine sand and silt, underlain by soft clays and silty clays to 50 ft

(NRCS, 2007). These soil types are characteristic of the Terrebonne Basin barrier

islands.

Prime or Unique Farmlands are not present in the Study Area.

4.2.1.1.1 Historic Conditions

Deltaic processes have played a significant role in the types of soil present in the

Study Area. The dynamic and episodic deltaic building processes alternates between

periods of seaward progradation of deltas (regressive deposition) and the

subsequent landward retreat of deltaic headlands as deltas are abandoned,

reworked, and submerged by marine waters (transgressive deposition). The types

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of soils present today in much of the Study Area are characterized by the

depositional environments associated with both of these phases of the deltaic cycle.

4.2.1.1.2 Existing Conditions

Isles Dernieres soils have been identified as Felicity and Scatlake soil units (USDA

Soils Survey, 2005). Felicity soil is a level to gently sloping, somewhat poorly

drained soil, which is formed in the sandy beach rim/dune complex along the Gulf of

Mexico shoreline. The soil is frequently flooded, and subject to scouring and

deposition by storm surge and sediment. The surface layer of Felicity soil is

typically grayish brown, loamy fine sand that extends to a depth of approximately

nine inches. The underlying material, dark gray loamy sand is typically measured

to a depth of approximately 60 inches (USDA Soils Survey, 2005).

The soils of Timbalier and East Timbalier Islands are similar to those found on Isles

Dernieres in that they are composed primarily of fine-grained, poorly developed

sands. The Felicity soils are classified as poorly drained, rapidly permeable, saline

sands in the beaches, dunes, and overwash regions, while the Scatlake soils are

mucky clays that are primarily located in the saline marshes (USDC, 1998). The

nearshore features of Timbalier and East Timbalier Islands are flat compacted

sand, with minor sandbar features in 6-8 ft of offshore water (USEPA, 2002).

The Scatlake unit is a level, very poorly drained, very mineral clay and muck soil

that was formed on the level lee side of the island from the remnant intratidal

deltaic marsh sediment. The surface layer, which is typically eight inches of dark

gray, very fluid muck, is positioned above approximately 75 inches of underlying

material that ranges from gray to dark gray muck, to very fluid clay (USDA, 2005).

4.2.1.2 Water bottoms

4.2.1.2.1 Historic Conditions

Beginning in the 1980s, the Louisiana Geologic Survey in conjunction with the

USGS and MMS began investigating the distribution and character of sand-rich

sediment within the shallow stratigraphy, (i.e., the upper 40 ft of the Study Area).

Suter et al. (1991) and Kindinger et al. (2001) conducted in-depth regional studies of

the offshore area. Combined, they collected thousands of miles of high-resolution

seismic reflection data and hundreds of vibracores for the purpose of identifying and

mapping sand-rich sediment resources.

The above referenced studies identified numerous inlet shoals and nearshore relict

distributary channels sources and a significant offshore sand source at Ship Shoal.

Potential nearshore sand sources include nearshore ebb-tidal shoals (e.g., Little

Timbalier Pass, Coupe Collin, Cat Island Pass), relict spits (e.g., Raccoon Island

paleo relict spits), and paleo distributary channels adjacent to the islands. These

resources may also provide fine sediments for marsh restoration.

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Potential sources of sediment for use in marsh restoration throughout the Study

Area include channel dredging of the Houma Navigation Channel (about 350,000 cy

per year from 1960 to 1980) and various sources adjacent to the Isles Dernieres

Islands (Figures 4-5 and 4-6, and Table 4-4; Suter and Penland, 1988; and Suter et

al., 1991). Kindinger et al. (2002) documented sand resources in the back bays and

in the channels west of East Timbalier Island. Considerable knowledge has been

gained through back-barrier and inlet geotechnical work in association with the

Terrebonne Basin CWPPRA projects described in Section 1.5 Prior Studies,

Reports, and Existing Projects.

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Figure 4-5. Locations of sediment resource targets in the area from Point

au Fer to the Isles Dernieres (Suter et al., 1991)

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Figure 4-6. Locations of sediment resource targets in the Timbalier and

Terrebonne bays area (Suter, et al., 1991)

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Table 4-4. Sediment resources targets

Target

Number Designation

Target

Number Designation

1 Marsh Island Distributary Channel 29 Timbalier Island Recurved Spit

2 Western Shell Reef Distributary Channel 30 Little Pass Timbalier Flood Tidal Delta

3 Central Shell Reef Distributary Channel 31 Little Pass Timbalier Ebb Tidal Delta

4 Eastern Shell Reef Distributary Channel 32 Timbalier Island Distributary Channels

5 Marsh Island Shoal 1 33 Raccoon Pass Flood Tidal Delta

6 Marsh Island Shoal 2 34 Belle Pass Distributary Channel

7 Southern Shell Reef Distributary Channel 35 Bayou Lafourche Distributary Channel

8 Western Point Au Fer Distributary Channel 36 Bayou Moreau Distributary Channel

9 Central Point Au Fer Distributary Channel 37 Cheniere Caminada Beach Ridges

10 Eastern Point Au Fer Distributary Channel 38 Caminada Pass Spit

11

Grand Caillou Distributary Channel Ebb

delta 39 Caminada Pass Ebb Tidal Dclta

12 Raccoon Point Distributary Channel 40 Grand Isle Shoreface

13 Raccoon Point Recurved Spit 41

Barataria Pass/Grande Terre Tidal

Channels

14 Relict Raccoon Point Recurved Spit 42 Barataria Pass Ebb Tidal Delta

15 Coupe Colin Flood Tidal Delta 43 Pass Abel Ebb Tidal Delta

16 Coupe Colin Ebb Tidal Delta 44 Quatre Bayou Pass Ebb Tidal Delta

17 Ship Shoal Distributary Channel 45 Cheniere Ronquille Distributary

18 Ship Shoal 46 Cheniere Ronquille Beach Ridges

19 Whiskey Pass Ebb Tidal Delta 47 Bayou Chaland Distributary Channel

20 Whiskey Pass Flood Tidal Delta 48 Chaland Pass Ebb Tidal Delta

21 Lake Pelto Beach Ridges 49 Grand Bayou Distributary

22 Lake Pelto Distributary Channel 50 Grand Bayou Pass Ebb Tidal Delta

23 Coupe Carmen Flood Tidal Delta 51 Shell Island Distributary Channel

24 Cheniere Caillou Beach Ridges 52

Western Scofield Bay Distributary

Channel

25 Caillou Distributary Channel 53 Central Scofield Bay Distributary Channel

26 Cat Island Pass Ebb Tidal Dclta 54 Eastern Scofield Bay Distributary Channel

27 Cat Island Pass Flood Tidal Dclta 55 Dry Cypress Bayou Distributary Channel

28 Cat Island Pass Tidal Channel

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4.2.1.2.2 Existing Conditions

Existing information and data related to potential sediment sources for beach,

dune, and marsh restoration in the Terrebonne Basin barrier island reach were

identified in the 2004 LCA Plan Appendix D (USACE, 2004c) and the final

programmatic EIS (USACE, 2004b). Supplementing the information in these

reports are additional environmental and geologic assessments, engineering

reports, geotechnical surveys and geophysical surveys (Finkl et al., 2005; Khalil et

al., 2006; Khalil et al., 2007; Kulp et al., 2001; LDNR, 2005b; LDNR and USEPA,

2007; Stone et al., 2004; USEPA, 2003a; and USEPA, 2003b). These data use

geophysical and geotechnical methods to assess geologic resource areas for offshore

sand sources and provide the geospatial extent of potential sediment sources for

back-barrier and marsh restoration using numerous core borings.

More recently, details of sand sources offshore of Whiskey Pass and Trinity Island

are reported in LDNR and USEPA (2007). Area 3 has an estimated 4.7 mcy of sand

available for beach restoration while New Cut still has approximately 2.5 mcy

available (S. Khalil, personal communication, August, 2008).

Ship Shoal, a large shore-parallel sand body, is located approximately from 11 to 32

miles from the barrier islands depending upon the specific fill area and lease block

location. It represents a defined source for the long-term maintenance for Isles

Dernieres and Timbalier Islands. Ship Shoal is the largest sand source in the

Terrebonne Basin and testing (LDNR, 2005a; USEPA 2003a and 2003b) has shown

sediment to be similar in quality to the native beaches and dunes of the Isles

Dernieres and Timbalier Reaches. With the proximity of the shoal to the Isles

Dernieres Reach, sand could be dredged and delivered to the coast by pipeline

dredges equipped with booster pumps. For the Timbalier Reach, sand could be

dredged and delivered via hopper dredges and pump-outs.

Sediments found in Ship Shoal vary based on stratigraphic position. Sediments in

the upper 16 ft (5 m) of the shoal (shoal crest) are comprised by very well sorted

quartz sand. The lower shoal (shoal front) ranges from 4 to 11 ft (1.2 to 3.4 meters)

thick and contains finer-grained sand compared to the shoal crest. The base of the

shoal contains poorly sorted finer-grained sand mixed with layers of silt and clay

(Penland et al. 1988 from Stone et al. 2004).

Kulp et al. (2001) stated large areas of Ship Shoal are also the sites of extensive

hydrocarbon infrastructure, presenting a technical difficulty for the efficient

removal of sediment. Suggested areas of sediment removal were offshore lease

blocks Ship Shoal 88, Pelto 12, and Pelto 13. Volumes, not considering the presence

of infrastructure within these blocks, were estimated at 74 mcy, 58 mcy, and 44

mcy, respectively (Figure 4-7).

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In association with MMS, recent studies have been conducted to establish a buffer

zone around oil infrastructure and other magnetic anomalies within the Ship Shoal

sand resource areas to ensure quality of borrow sediments and safety of dredging

operations (Michel, 2004; and Nairn et al., 2004). During 2003, detailed

geotechnical investigations were conducted to more accurately evaluate sand

volumes that are potentially available for coastal restoration within Ship Shoal

Blocks 88 and 89 and South Pelto Blocks 12 and 13 (USEPA, 2003a and 2003b).

Figure 4-7. Ship Shoal Sand Resource (Kulp et al., 2001)

In South Pelto, Blocks 12 and 13, analyses of over 410 line miles of geophysical data

and geotechnical exploration identified primarily clean sand (D50 grain size 0.15 to

0.2 mm) with less than 5% silt in upper stratigraphic units that ranged in thickness

from approximately 13 to 20 ft over an area of about 10.4 mi2. Combined volumes of

three closely spaced potential borrows, which occupy portions of five MMS lease

blocks, amounted to approximately 28.3 mcy (Khalil et al., 2007; and Finkl et al.,

2005).

During July 2006, LDNR and the Louisiana State University (LSU) Coastal Studies

Institute (CSI) for the first time conducted a reconnaissance geophysical survey

(report under preparation) over Ship Shoal Blocks 85, 86, 98, and 99. Subsequently

during July/August 2007, additional geophysical data were collected from this

portion of Ship Shoal to ascertain and confirm several magnetic anomalies. On the

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basis of this reconnaissance geophysical survey, it was estimated that

approximately 124 mcy is available to a depth of approximately 13 ft.

4.2.2 Hydrology

This resource is institutionally significant because of the National Environmental

Policy Act (NEPA); Clean Water Act; Flood Control Act of 1944; Coastal Barrier

Resources Act; Rivers and Harbors Act of 1899; River and Harbor and Flood

Control Act of 1970; Watershed Protection and Flood Prevention Act; Submerged

Land Act; Coastal Zone Management Act; Safe Drinking Water Act; Estuary

Protection Act; Resource Conservation and Recovery Act (RCRA); Comprehensive

Environmental Response, Compensation, and Liability Act (CERCLA); and

Executive Order 11988 Floodplain Management. This resource is technically

significant because Civil Works water resources development projects typically

impact (positively or negatively) the interrelationships and interactions between

water and its environment. This resource is publicly significant because the public

demands clean water, hazard-free navigation, protection of estuaries and

floodplains.

The Terrebonne Basin drainage area encompasses approximately 1,455 square

miles. Major navigation channels within the basin are the Atchafalaya River, Wax

Lake Outlet, Houma Navigation Canal, Gulf Intracoastal Waterway (GIWW), and

Lower Atchafalaya River (LOSCO, 1999). These navigation channels introduce

and/or compound marine influences in many of the interior coastal wetlands and

water bodies within the Terrebonne Basin (USACE, 2004a).

4.2.2.1 Flow and Water Levels

4.2.2.1.1 Historic Conditions

The Mississippi River and its distributaries historically provided immense volumes

of land-building sediment and nutrients throughout Louisianas coastal areas.

Levee activity along the Mississippi River in coastal Louisiana began as early as

the 1700s. By the early 1900s the levee system along the Mississippi River was

nearly complete protecting the surrounding areas by reducing the number of

overbank flooding events. A consequence of this construction was that most of

Louisianas coastal wetlands were deprived of the sediment rich floodwaters and

nutrients that help sustain the surrounding wetlands against land loss and

subsidence. The flood protection afforded by the levee system allowed for increased

economic development and human habitation in the coastal areas. With this

development came the construction of roads, railways, ports and harbors, oil and

gas access canals within the wetlands, and drainage projects. All of the activities

lead to the disruption of the deltaic cycle and natural hydrology to a point where the

land being lost exceeded the land created through natural processes (USACE,

2004a).

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The coastal water level patterns within the LCA TBBSR Study Area is typically a

diurnal tidal signal of 3040 cm (1216 in) which), which is superimposed on a

lower frequency (~3 days), higher amplitude (up to 1 meter) signal. The tidal

fluctuations explain 6070% of the water level variations. The lower frequency

signal is mainly due to atmospheric forcing events (frontal passage). In general, the

coastal water levels exhibit ~1 m (3.2 ft) of movement throughout the year (tides

and fronts combined). The tidal amplitude decreases as one moves inland.

Water levels surrounding the barrier islands are primarily controlled by tides and

winds. Smaller contributing factors are wave action, freshwater run-off from the

marshes in the northern section of the basin, and to a lesser degree, atmospheric

pressure. Wind-driven set-up can alter water levels to a greater extent than tides,

which are diurnal and of low magnitude in this area. The maximum tidal range is

about two ft (0.6 m).

4.2.2.1.2 Existing Conditions

The Terrebonne Basin wetland communities experience different hydrological

influences. The eastern portions of the basin are hydrologically isolated from the

influence of the major sediment rich waters of the Atchafalaya and Mississippi

Rivers. The same is true for the northwestern portions, both above and below the

GIWW, where the hydrologic influence comes mainly from a widely variable pattern

of Atchafalaya River backwater effect, rainfall runoff events, and marine processes.

Conversely, the southwestern portion of the basin receives nourishment from the

Atchafalaya River and has some of the lowest land loss rates in the State (USACE,

2004a).

The present LCA TBBSR Study Area still maintains most of the features of typical

natural estuaries. Even though the changes in hydrology, salinity and marshes

have been severe, there is still a fresh to salt gradient, flow across many marshes,

and an active fish and shellfish nurseryimportant aspects of estuarine function

and integrity.

The tidal range near the barrier islands is relatively small compared to areas along

the east and west coast. The average range is on the order of 1 ft with a fortnightly

maximum range of 1 to 2 ft. Frontal passages can increase the normal tidal range

up to 2 ft and storm surges associated with tropical storms and hurricanes can

reach magnitudes several times the normally encountered range. Hurricane storm

surge will typically be on the order of 3 to 4 ft once every 10 years and 7 ft once

every 20 years (USEPA, 1997a).

Waves

The wave climate along the Louisiana coast is a product of seasonal wind patterns

and the passage of tropical and extra-tropical storms. The distribution of deepwater

wave energy is known from several NOAA stations that are located between 22 and

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118 miles offshore. The nearshore wave climate is less well known, and comes

primarily from data sets that are collected at Wave Current Information System

(WAVCIS) stations, an observing system along the Louisiana continental shelf

operated by the Louisiana State University, Coastal Studies Institute (CSI).

Deepwater Waves

Deepwater wave characteristics for central Terrebonne Basin were collected from

NOAA Station 42017. The station is located approximately 68 miles offshore where

the water depth is approximately 2000 ft. The period of record for the significant

wave height and dominant wave period information is 1 year, 1989. The data

indicates an average deepwater wave height of 2.5 ft and an average wave period of

5 seconds (USACE, 2004c). NOAA Station 42001, which is located 180 nautical

miles south of Southwest Pass, La in 3246 meters of water has a period of record

from January 1976 to December 2001. At this station, the monthly mean

significant wave height ranged from approximately 1.6 ft to 4.6 ft and mean wave

periods ranged between approximately 4.1 to 5.0 seconds (NOAA, 2009).

Nearshore Waves

The following nearshore waves information is incorporated by reference from

Appendix D  Louisiana Gulf Shoreline Restoration Report  of the Louisiana

Coastal Area (LCA) Ecosystem Restoration Study (per NEPA Section 1502.21;

USACE, 2004c).

The nearshore WAVCIS station for Terrebonne Basin, CSI-5, is located

approximately 1.2 miles offshore of Timbalier Island approximately at the 16-ft

isobath. Wave and wind rose data for Station CSI-5 (Figure 4-8) depicts seasonal

variation in wave climate for the central Louisiana coast. The data demonstrate a

high correspondence between dominant wave approach and wind direction. For the

period between mid-spring and mid-fall, winds are predominantly from the south,

with the highest frequency of occurrence from the southeast. The dominant wave

approach is from the southeast quadrant (40% probability). During late fall to early

spring, the wind regime is controlled by the passages of cold fronts. These weather

systems commonly produce winds blowing from the south (pre-frontal) and then

from the north (post-frontal). However, the northeasterly winds blow offshore in

central Louisiana, which cancels propagation of longer waves from the south near

the coast. The fetch to the north of Station CSI-5 is limited, and waves are not

generated during these post-frontal events. Therefore, the dominant waves

(probability ~ 80%) come from the southeast quadrant and are the chief control of

sediment transport patterns along the central Louisiana shoreline. Data from the

same WAVCIS station, CSI-5, illustrates the seasonality in wave energy in

Louisiana (Figure 4-9). These graphs represent time series of wave height from May

through August 2001 as measured by CSI-5. The lower graph shows the wave

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height distribution at the same location for a winter period extending from

November 2001 through February 2002.

Typically, waves vary from approximately 0.23 - 2.65 ft, the latter being a function

of weak storms in the GOM. It is apparent, however, that tropical cyclones can

generate considerably larger waves during summer months where waves over 6.2 ft

in height were recorded for a period in early June, 2001. During winter months, the

effects of cold front passages over the Louisiana coast are apparent in the graph as

a series of sharp increases in wave height. During the four-month period from

November 2001 to February 2002, a total of 20 cold front passages can be identified

with six events resulting in energetic sea states and wave heights ranging from

approximately 3.3 to 6.6 ft. Therefore, with the exception of infrequent tropical

cyclone activity in summer months, the high frequency of frontal passages over the

Louisiana coast plays a critical role in generating and sustaining higher waves

during winter months (USACE, 2004c).

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Figure 4-8. Wave (right) and Wind (left) Roses for data collected from

WAVCIS Station CSI-5: Summer (top) and Winter (bottom) (USACE,

2004c)

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Figure 4-9. Time Series of Wave Height Data from WAVCIS Station

CSI-5: Summer (top) and Winter (bottom) (USACE, 2004c)

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Storms and Hurricanes

The following storms and hurricanes information is incorporated by reference from

Appendix D  Louisiana Gulf Shoreline Restoration Report  of the Louisiana

Coastal Area (LCA) Ecosystem Restoration Study (per NEPA Section 1502.21;

USACE, 2004c). Penland and collaborators have analyzed changes in the Louisiana

shoreline, spanning a century and a half (Penland, et al., 2005). Their graphical

presentations of land loss data clearly demonstrate the impacts of multiple

hurricanes (1979, Bob and Claudette; 1985, Danny, Elena, and Juan; 1992, Andrew)

on the Terrebonne Basin Barrier Islands, most of which lost hundreds of acres. The

catastrophic losses from Andrew precipitated numerous restoration projects,

sponsored by CWPPRA and FEMA. The hurricanes of 2005, Katrina and Rita, and

2008, Gustav and Ike, undid much of that repair work, and further degraded most

of the islands.

Cold Fronts

In an average year, 20 to 30 cold fronts will pass through coastal Louisiana. The

resulting response of the coastal waters is the initial increase in tidal amplitudes,

which causes waves to break higher on the beach, overwashing low barrier islands.

Elevated tides increase the flow of ocean water into the bays and marsh systems

behind the barrier islands. As floodwaters reside and exit the inlets with passage of

the front, abrupt changes in wind direction from southerly to northerly cause

increased wave heights in the bays. This continuous process is believed to be

responsible for the chronic shoreline erosion behind the barrier islands.

Tides

The following tides information is incorporated by reference from Appendix D 

Louisiana Gulf Shoreline Restoration Report  of the Louisiana Coastal Area (LCA)

Ecosystem Restoration Study (per NEPA Section 1502.21; USACE, 2004c).

In the delta region including Raccoon Pass (west), Grand Isle (central), and the

northern Chandeleur Islands (east) tides are strongly diurnal. At Raccoon Pass, the

tidal range varies from a low of 0.5 ft during equatorial tidal conditions to a high of

3.2 ft during tropic tides.

Sea-level Rise and Subsidence

Eustatic Sea-level Change

Eustatic sea-level change is the global change of the oceanic water level. According

to IPCC (2007), the global mean sea-level (MSL) rose at an average rate of about 1.7

mm/yr during the twentieth century. Recent climate research has documented

global warming during the twentieth century, and has predicted either continued or

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accelerated global warming for the twenty-first century and possibly beyond (IPCC,

2007). Based on USACEs projections of future changes in MSL (USACE, 2009b)

designated as low/historic, intermediate and high, the corresponding eustatic sealevel changes between 2006 and 2062 are estimated at 95 mm, 222 mm, and 635

mm, respectively.

Relative Sea-level Change

Relative sea-level change is the term applied to the difference between the change

in eustatic sea-level and the change in land elevation. The combination of

subsidence (land sinking) and eustatic sea-level rise are likely to cause the

landward movement of marine conditions into estuaries, coastal wetlands, and

fringing uplands (Day and Templet, 1989; Reid and Trexler, 1992).

According to NOAA (http://tidesandcurrents.noaa.gov), the relative MSL trend at

Grand Isle, LA is 9.24 mm/yr with a 95% confidence interval of +/- 0.59 mm/yr.

Using the USACE (2009b) projections of future changes in MSL, the estimated sealevel changes in the LCA TBBSR Study Area between 2006 and 2062 are 0.517 m,

0.644 m, and 1.058 m, for the low/historic, intermediate and high rates,

respectively. These are the highest rates along the contiguous United States and

helps to explain coastal evolution in Louisiana. Subsidence and rising sea-level are

also largely responsible for shoreline erosion and the transgressive nature of most of

the barrier islands in Louisiana (USACE, 2004c).

Tidal Inlets and Tidal Prism Dynamics

The following tidal inlets and tidal prism dynamics information is incorporated by

reference from Appendix D  Louisiana Gulf Shoreline Restoration Report  of the

Louisiana Coastal Area (LCA) Ecosystem Restoration Study (per NEPA Section

1502.21; USACE, 2004c).

Barrier island development along the Louisiana coast is a product of river avulsion

and the subsequent reworking of distributary headlands (Penland et al., 1988). The

size and number of tidal inlets along the barrier coast are controlled, in part, by the

volume of water (tidal prism) moving into and out of back-barrier bays. The historic

evolution of these tidal inlets is a product of changes in extent and configuration of

the back-barrier bays.

Generally, tidal exchange between back-barrier bays and the GOM has increased

along the Deltaic Plain since at least the 1880s due to widespread conversion of

wetlands and salt marsh to open water areas. For example, in the mid-1800s the

Isles Dernieres were backed by Lake Pelto. At that time, the lake was surrounded

by a near uninterrupted expanse of marshland. Over the subsequent hundred years

to the mid-1900s, land subsidence, wave erosion of the marsh shoreline, and

dredging activity transformed the lake into a large continuous sound having an

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open connection to Caillou Bay to the west and Terrebonne Bay to the east. The

historic changes to the Isles Dernieres are symptomatic of the wetland loss and

barrier evolution along the entire Deltaic Coastal Plain.

Tidal prism dynamics and the pattern of tidal exchange dictate the occurrence and

geometry of tidal inlets along the various barrier chains. Tidal inlets along the

Timbalier Islands have highly variable geometries due to the segmented nature of

the barrier system. Much of the tidal exchange between the back-barriers of Caillou

Bay, Terrebonne Bay and Timbalier Bay and that of the GOM occurs through broad

shallow channels where the transgressive barriers have undergone extensive

erosion. However, there are several relatively deep passes 20 to 33-ft deep that are

maintained by strong tidal currents on the order of 3.3 ft/s.

Estuarine Circulation

The following estuarine circulation information is incorporated by reference from

Appendix D  Louisiana Gulf Shoreline Restoration Report  of the Louisiana

Coastal Area (LCA) Ecosystem Restoration Study (per NEPA Section 1502.21;

USACE, 2004c).

Circulation of coastal waters depends on driving forces such as tides, wind, and

atmospheric pressure. Along the complex Louisiana coast, circulation mechanisms

go beyond these driving forces to include high rainfall; the large volume of fresh

water introduced by the Mississippi and Atchafalaya Rivers; currents induced by

density differences and mixing processes of these two masses of water; local

shoreline and bathymetric features such as the Mississippi River mouth, barrier

islands, marshes, inlets, bays, and so forth.

Tidal currents in Louisiana are relatively small, due to the small tidal amplitude. In

the absence of wind, density effects and barometric pressure gradients, these

currents reach magnitudes of approximately 0.3 to 0.5 ft/s. Estimates and

observations suggest that tidal currents are stronger at the surface of the water

column and decrease with increasing depth. This occurrence is primarily due to the

encounter of denser and heavier salty gulf waters in deeper regions, which are less

likely to respond to small tide variations. Although small in magnitude in open

coastal waters, tidal currents can reach velocities of approximately 1.7 ft/s at

estuary and barrier island inlets, depending on the inlet dimensions. The amount of

circulation attributed to rising and falling tides or tidal induced circulation is

measured as a function of the spatial and temporal variability of tides along the

Louisiana coast. There is a seven-hour lag before high water from the east coastal

zone reaches the west coastal zone, with typical tidal ranges between 1 to 2 ft

depending on the time of month and year.

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down, seiche, and wind-waves. Similarly, the presence of front-like weather during

the winter and storms during hurricane season enhances these processes by

producing dynamic wind conditions. The speed and direction of these winds shift

abruptly, creating strong gusts. Changing wind speed and direction cause the

generation and transformation of waves along the Louisiana coast. Wind and

barometric pressure induced circulation is critical and dominant in back bays,

enclosed bays, lakes, marshes, and sub-tidal areas. These processes are

characterized by extreme water level fluctuations, and are responsible for a

significant amount of the erosion taking place along the Louisiana coast.

Another important process in Louisiana is the freshwater exchange and mixing

attributed to the Mississippi and Atchafalaya Rivers, and the hundreds of streams

and bayous along the coast. The two rivers combined account for a mean flow of

approximately 700,000 cfs, with seasonal variations of up to 280,000 cfs. The low

density freshwater meets and mixes with the higher density Gulf waters. In the

process, the density difference between the two water masses causes density

currents. Typically the surface water column is fresh or brackish depending on the

strength of the discharge, and the bottom water column is salty. The velocity of the

density currents varies in magnitude and is a function of the density difference,

discharge velocity, and available head difference. Although relatively small for the

most part, these currents can propagate several miles upstream or downstream

given the presence of favorable conditions. Periodic intrusion of saltwater can be

detrimental to critical habitat in the bays and marshes. Episodic exposure to highly

saline water leads to marsh deterioration and systematic land erosion. Salt water

intrusion in the Mississippi River has been observed to travel more than 50 miles

upstream during low flow. Similarly, during periods of low rainfall and hence low

fresh water discharge, salt-water wedges slowly propagate onshore for several miles

through inlets and bays.

4.2.2.2 Sedimentation and Erosion

4.2.2.2.1 Historic Conditions

Sediment quality is defined as the suitability of the habitat for supporting

designated uses, including, but not limited to, benthic fauna and emergent wetland

plants. Storm events, flowing water, and other factors can potentially re-mobilize

sediments. Aquatic sediments are essential in maintaining the structure

(assemblage of organisms) and function (processes) of aquatic ecosystem. Sediment

quality is important due to the role that sediments play in supporting community

productivity. The productivity of green plants, algae, and bacteria build the

foundation of food webs upon which higher aquatic organisms depend. Sediments

provide essential habitats for epibenthic (live on sediments) and infaunal (live in

sediments) invertebrates and demersal fish, which represent important food sources

for amphibians, reptiles, fish, birds, and mammals. In addition, many fish and

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amphibian species utilize sediments at stages in their life cycles for the purposes of

spawning, incubation, refuge, and over-wintering (LDEQ, 2005).

As described above, the Deltaic Cycle has resulted in the creation of barrier islands,

followed by their gradual degradation as the river shifted course, the sediment

supply diminished, and a new delta lobe formed. There are several drivers for the

gradual degradation: loss of sediment, subsidence, and sea level rise are all

insidious but persistent. The three more obvious drivers are tropical storms and

hurricanes, discussed above, and longshore and cross-shore sediment transport,

described below. Longshore transport is facilitated by the passage of seasonal

storm fronts as well as tidal flow, which deposits sediment in ebb- and flood-tide

shoals. Cross-shore sediment transport is facilitated by tropical storms and

hurricanes, which drive the Gulf across the islands, carrying sediment over and

beyond the dune system, or washing it off the dune and beach, to be deposited in the

nearshore. Rosati and Stone (2009) considered overwash and breach formation

(extreme examples of cross-shore transport) to be the main drivers of morphological

change along the coastline from the Chandeleur Islands to the Isles Dernieres.

4.2.2.2.2 Existing Conditions

Longshore Sediment Transport

The following longshore sediment transport information is incorporated by

reference from Appendix D  Louisiana Gulf Shoreline Restoration Report  of the

Louisiana Coastal Area (LCA) Ecosystem Restoration Study (per NEPA Section

1502.21; USACE, 2004c).

Longshore sediment transport is the movement of sediment parallel to the shore.

This process is a result of breaking and shoaling waves suspending sand from the

bottom and the displacement of the sediment down-drift by the longshore current.

The magnitude of the longshore current intensifies with increasing wave height and

breaker angle. In addition to these wave parameters, the rate of transport is a

function of beach or barrier orientation, offshore shelf slope, and local depth. In

coastal Louisiana, direct measurements of longshore transport are limited. The

rates of transport are typically based on historical studies of shoreline erosional and

depositional trends, sedimentation patterns in the vicinity of coastal structures, and

on numerical wave modeling. Overall net longshore sediment transport along the

Isle Dernieres Reach is directed westward at an approximate rate of 45,000 cy per

year (cy/yr) and overall net longshore sediment transport along the Timbalier Reach

is directed westward at an approximate rate of 15,000 cy/yr (Table 4-5).

Table 4-5. Longshore Sediment Transport Estimates for the Isle Dernieres

and Timbalier Islands Reaches (Georgiou et al., 2005)

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Geographic Location Coverage Rate

(cy/yr) Direction From: To:

Isle Dernieres reach East Island Raccoon Island 43,000 Westward

Timbalier Island reach Raccoon Pass Cat Island Pass 14,000 Westward

Isles Dernieres Reach

Sediment transport along the Isles Dernieres is complex given its fragmented

nature (Georgiou et al., 2005). Overall, sediment moves in a westerly direction along

the Isles Dernieres reach, although local bidirectional transport occurs on Trinity

and Whiskey Islands. Sediment movement around Whiskey Pass is largely

nonexistent. Waves propagating through the pass break along the marsh shoreline

in Lake Pelto (Stone and Zhang, 2001). This process indicates that sand is

transported predominantly onshore through the pass, thereby minimizing sediment

bypassing that down drift Whiskey Island. Although net transport rates are

variable, net westward transport of approximately 78,000 cy/yr has been derived

numerically (Stone and Zhang, 2001).

Timbalier Reach

According to Georgiou et al. (2005), net sediment movement along the Timbalier

Islands is to the west, and the rate increases from east to west. Sub-scale transport

trends are evident on both islands. However, the sand transport system along the

island has been greatly diminished due to the extent of coastal structures in the

area. The potential for transferring sand from the Caminada Moreau headland to

East Timbalier Island is minimal, given the large width of Raccoon Pass and the net

landward transport of sand to its flood tidal delta (Georgiou et al., 2005). Kulp et al.

(2002) have documented extensive growth of this flood tidal delta suggests that

little sand bypasses the inlet. Rather, the sand is worked onshore into Timbalier

Bay. Bypassing of sand across Little Pass Timbalier is also minimal. Waves

propagate through this inlet prior to breaking inside Timbalier Bay. Further, the

jetties at Belle Pass on the western end of the Caminada Headland interrupt the

natural flow of sediment, thus reducing the volume transported drown drift (CEC

and SJB, 2008).

Similarly, net transport is westward along Timbalier Island with a net increase in

rate along the eastern flank of the barrier island to approximately 65,000 cy/yr

(Georgiou et al., 2005). Conversely, the rate decreases to the western end of the

island. This pattern suggests that sand eroded from the eastern flank is transported

to the west where it is deposited along the west flank of the barrier and in Cat

Island Pass (Georgiou et al., 2005).

Cross-Shore Sediment Transport

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The following cross-shore sediment transport information is incorporated by

reference from Appendix D  Louisiana Gulf Shoreline Restoration Report  of the

Louisiana Coastal Area (LCA) Ecosystem Restoration Study (per NEPA Section

1502.21; USACE, 2004c).

Cross-shore sediment transport is the movement of sediment in a direction

perpendicular to the shoreline. Rates of cross-shore sediment transport are difficult

to quantify by direct measurements. As a result, little is known about the dynamics

of this process. Cross-shore movement of sediment includes the sand that is eroded

from the beach and transported offshore during storms, as well as the sand moved

onshore by the process of overwash or during post- storm recovery by fair-weather

waves. At the same time, storm waves breaking over low barriers wash sand into

back-barrier marshes. This process provides a mechanism for the barrier islands to

migrate landward and to reestablish sand platforms that are colonized by marsh

vegetation.

4.2.2.3 Water Use and Supply

4.2.2.3.1 Historic Conditions

There were no historic sources of fresh water in the Study Area. Historic water use

was limited to personal consumption. Water was either transported to the Study

Area or obtained by capturing rain water onsite with cisterns.

4.2.2.3.2 Existing Conditions

There are no onsite sources of fresh water in the Study Area. Supplies of potable

water are either transported to the Study Area or obtained by capturing rain water

onsite with cisterns.

4.2.2.4 Groundwater

4.2.2.4.1 Historic Conditions

Due to the saline environment, groundwater resources have not historically been

utilized in the Study Area.

4.2.2.4.2 Existing Conditions

Due to the saline environment, groundwater resources are not utilized in the Study

Area.

4.2.3 Water Quality and Salinity

4.2.3.1 Water Quality

This resource is institutionally significant because of the National Environmental

Policy Act of 1969; the Clean Water Act; the Coastal Zone Management Act; and the

Estuary Protection Act. This resource is technically significant because the water

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quality supports most physical, chemical, geological, and biological processes

throughout the entire estuarine system. This resource is publicly significant

because the public demands clean water and healthy wildlife and fisher species for

recreational and commercial use.

4.2.3.1.1 Historic Conditions

Historic and current water quality issues for rivers and streams in coastal

Louisiana include the transport of nutrients, pesticides, synthetic organic

compounds, trace elements, suspended sediment, and bacteria. The Louisiana

Department of Health and Hospitals coordinates with the LDEQ, the LDWF, and

the Louisiana Department of Agriculture and Forestry to issue water body

advisories aimed at protecting the publics health.

The LDEQ assesses four categories for water use under the Louisiana

Environmental Regulatory Code (LAC Title 33, Chapter 11) that would apply to the

Study Area. Primary Contact Recreation includes activities such as swimming,

water skiing, tubing, snorkeling, skin diving, and other activities that involve

prolonged body contact with water and probable ingestion. Secondary Contact

Recreation includes fishing, wading, and recreational boating, and other activities

that involve only incidental or accidental body contact and minimal probability of

ingesting water. Fish and Wildlife Propagation includes the use of water by aquatic

biota for aquatic habitat, food, resting reproduction, and cover, including indigenous

fishes and invertebrates, reptiles, amphibians, and other aquatic biota consumed by

humans. Oyster Propagation includes the use of water to maintain biological

systems that support economically important species of oysters, clams, mussels, and

other mollusks consumed by humans so that their productivity is preserved and the

health of human consumers of these species is protected. In the Study Area, Oyster

Propagation was identified as being impaired in some areas. The USEPA and

LDEQ identified low dissolved oxygen levels and high fecal coliform levels as the

suspected causes for impairment for Oyster Propagation, but were not able to

identify the sources of these problems (LDEQ, 2005).

4.2.3.1.2 Existing Conditions

According to the 2002 Water Quality Management Plan, Water Quality Inventory,

Section 305(B) report (LDEQ, 2002), the Terrebonne Basin Coastal Bays and Gulf

waters were listed as fully supporting all designated uses except fish and wildlife

propagation. The suspected causes of impairment are upstream sources and

atmospheric deposition of phosphorus, nitrogen, and mercury. Discharges

associated with drilling such as water-based mud and cuttings have been released

in the region over the past several decades. All discharges are periodically tested

and must meet the National Pollutant Discharge Elimination System (NPDES)

limits set by the USEPA (USEPA, 2005a). These limits are necessary since

produced-water discharge may have higher salinity levels, organic content and

dissolved metals, and lower dissolved oxygen levels than the receiving water.

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Hydrocarbons found in the GOM come primarily from natural seeps and

anthropogenic shore-based and offshore sources. However, since the islands are

significantly removed from the mainland, pollution from shore-based sources is

unlikely.

The back-bay estuaries of Isles Dernieres are listed as fully supporting primary

contact recreation, secondary contact recreation, and oyster production, but do not

fully support fish and wildlife propagation (USACE, 2004b). This system has been

listed as impaired for one or more uses, but the cause of impairment is listed as a

non-pollutant (USDA, 2005). The suspected impairment, turbidity, is caused by

the close proximity of the GOM, erosion, and suspended sediments in the longshore

currents from Mississippi River discharge. The islands contain no fresh surface

water, and due to the distance from any significant source, contain no threat of fecal

coliform contamination. Consequently, there are no apparent water quality

problems for the Isles Dernieres or Timbalier Islands (USEPA, 2002).

4.2.3.2 Salinity Regimes

This resource is institutionally significant because of the National Environmental

Policy Act of 1969, the Coastal Barrier Resources Act, and the Coastal Zone

Management Act. This resource is technically significant because of the role that

salinity plays in land loss and the survival, distribution, and impacts to plants,

wildlife, and fisheries resources. This resource is publicly significant because

alteration of salinity regimes can accelerate land loss and adversely impact

commercial and recreational fishery opportunities.

4.2.3.2.1 Historic Conditions

The Louisiana Department of Wildlife and Fisheries (LDWF) has measured salinity

in Terrebonne Bay as part of its finfish-sampling program consistently since 1981.

Based on those data, which were collected at least monthly and often several times

per month from March 1981 to May 2000, salinity in the bay ranged from 3.4 parts

per thousand (ppt) to 29.3 ppt with a mean salinity of 16.6 ppt (USFWS, 2003).

This is consistent with data used by the CWPPRA Wetlands Valuation Assessment

for the Timbalier Island Dune and Marsh Creation Project (TE-40), which indicated

an annual salinity of 20 ppt for this area (USEPA, 2002).

4.2.3.2.2 Existing Conditions

Barrier islands restrict water exchange with estuaries behind them, provide storm

surge protection to wetlands and human infrastructure, and modify currents and

salinity within the bay system. According to the Louisiana Gulf Shoreline

Restoration Report Louisiana Coastal Area (LCA) 2004 Study, a comprehensive

model that can evaluate the spatial and temporal links that barrier islands have

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with the interior bays and coastal marshes is unavailable. The study showed that

the barrier islands influence the hydrodynamics of the mixing zone but the

hydraulic conveyance of the embayment and the marsh are probably more

important. The more open water and conveyance channels in the marshes, the

greater the penetration of tidal energy into the marsh and the farther the mixing

zone of fresh and saltwater will move into the marsh. Swenson (2000) found that

coastal salinities in the central and eastern portions of coastal Louisiana were

inversely proportional to Mississippi River discharge, with a range of 10 to 20 ppt

but with a fairly wide distribution.

Barrier islands are critical in maintaining salinity gradients, which in turn is vital

for proper functioning of the associated estuarine systems (Knotts, et al., 2006).

Without these islands, the estuaries deteriorate and higher salinity Gulf of Mexico

waters invade the lower salinity interior wetlands and the estuarine gradient

between them would collapse and its productivity would be destroyed (Penland et

al., 2003).

4.2.4 Air Quality

4.2.4.1 Historic Conditions

This resource is institutionally significant because of the Clean Air Act of 1963, as

amended, and the Louisiana Environmental Quality Act of 1983, as amended. Air

quality is technically significant because of the status of regional ambient air

quality in relation to the National Ambient Air Quality Standards (NAAQS). Air

quality is publicly significant because of the desire for clean air and public health

concerns expressed by many citizens.

National air quality standards have been set by the USEPA for six common

pollutants (also referred to as "criteria pollutants") including: ozone, particulate

matter, carbon monoxide, nitrogen dioxide, sulfur dioxide, and lead. States are

required by the Code of Federal Regulations to report to the USEPA annual

emissions estimates for point sources (major industrial facilities) emitting greater

than, or equal to, 100 tons per year of volatile organic compounds, nitrogen dioxide,

sulfur dioxide, particulate matter less than 10 microns in size; 1,000 tons per year

of carbon monoxide; or 5 tons per year of lead. Since ozone is not an emission, but

the result of a photochemical reaction, states are required to report emissions of

volatile organic compounds (VOC), which are compounds that lead to the formation

of ozone.

4.2.4.2 Existing Conditions

Terrebonne and Lafourche Parishes were both designated as attainment areas for

ozone for the 1997 Ground-level ozone standard according to the following EPA

website:

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(http://www.epa.gov/ozonedesignations/1997standards/regions/region6desig.htm).

In a letter to the EPA from the Louisiana Department of Environmental Quality

dated March 12, 2009, regarding 2008 Ozone National Ambient Air Quality

Standards (NAAQS), the State of Louisiana recommended that Terrebonne Parish

be listed as unclassifiable and Lafourche Parish be designated as nonattainment.

This information was obtained from the following EPA website:

http://www.epa.gov/ozonedesignations/index.htm) (USEPA 2009).

4.2.5 Noise

4.2.5.1 Historic Conditions

Noise is institutionally significant because of the Noise Control Act of 1972 that

declares the policy of the United States to promote an environment for all

Americans free from noise that jeopardizes their health or welfare; and the

Occupational Safety and Health Standards (29 CFR, part 1910) regarding

protection against the effects of noise exposure. Noise is technically significant

because noise can negatively affect the physiological or psychological well-being of

an individual (Kryter, 1994) ranging from annoyance to adverse physiological

responses, including permanent or temporary loss of hearing, and other types of

disturbance to humans and animals, including disruption of colonial nesting birds.

Noise is publicly significant because of the public's concern for the potential

annoyance and adverse effects of noise on wildlife and humans.

4.2.5.2 Existing Conditions

Noise is typically associated with human activities and habitations, such as

operation of commercial and recreational boats, water vessels, air boats, and other

recreational vehicles; operation of machinery and motors; and human residentialrelated noise (air conditioner, lawn mower, etc.). However, the Study Area includes

remote barrier islands and offshore sediment borrow areas. The noise from distant

urban areas and offshore oil and gas production facilities surrounding the Study

Area has little if any impacts on the area.

In recent years concerns have been raised regarding underwater noise and potential

impacts on aquatic organisms. There are a wide variety of noise-generating human

activities in the marine environment. Very few studies if any have been conducted

near dredge operations for island restoration projects. A brief explanation of dredge

techniques, procedures, and average time frame of these types of projects are as

follows. Dredging typically last an average of 348 days. A cutterhead dredge is

commonly used to remove material from the borrow site in which it is transferred to

the island restoration area. The cutterhead is mounted on a ladder that is lowered

to the sea bottom and is swung back and forth removing any material in its path.

The material is pump to the discharge site in which the island restoration begins to

take effect. Noise generated from the dredge will be temporary and last until the

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amount of borrow material needed is placed in the fill template. Only the area in

which the dredge operates will be exposed to the underwater noise.

4.2.6 Vegetation Resources

Coastal vegetation resources are institutionally significant because of the Coastal

Barrier Resources Act of 1982; Coastal Zone Management Act of 1972; Emergency

Wetlands Resources Act of 1986; Estuary Protection Act of 1968; Fish and Wildlife

Conservation Act of 1980; the Fish and Wildlife Coordination Act of 1958, as

amended; Migratory Bird Conservation Act; Migratory Bird Treaty Act; Endangered

Species Act of 1973 (ESA); Magnuson Fishery Conservation and Management Act

1990; National Environmental Policy Act of 1969; the North American Wetlands

Conservation Act; the Water Resources Development Acts of 1976, 1986, 1990, and

1992; and Executive Order 13186 Migratory Bird Habitat Protection. Coastal

vegetation resources are technically significant because they are a critical element

of the coastal habitats. In addition, coastal vegetation resources serve as the basis

of productivity, contribute to ecosystem diversity, provide various habitat types for

fish and wildlife, and are an indicator of the health of coastal habitats. Coastal

vegetation resources are publicly significant because of the high priority that the

public places on their aesthetic, recreational, and commercial value.

4.2.6.1 Riparian Vegetation

4.2.6.1.1 Historic Conditions

Riparian wetland vegetation was not historically present in the Study Area.

4.2.6.1.2 Existing Conditions

Riparian wetland vegetation is not currently present in the Study Area.

4.2.6.2 Wetland Vegetation

4.2.6.2.1 Historic Conditions

Visser and Peterson (1995) identified 12 plant species on transects extending across

entire barrier islands across Barataria-Terrebonne estuary. The dominant species

included marsh hay cordgrass (Spartina patens), saltwort (Batis maritima) blackmangrove (Avicennia germinans), coastal dropseed (Sporobolus virginicus),

perennial pickleweeds (Salicornia bigelovii) and seaoxeye (Borrichia frutescens).

The spatial distribution of these species was determined by elevation and exposure

to the Gulf of Mexico. The succulent species and vines occupied the lower beach

face, wire-grass occupied the highest elevations, and smooth cordgrass and black

mangrove dominated the protected bayside flats (Mac et al. 1998).

Louisiana Geological Survey conducted vegetation surveys in 1987 and 1988 on

Isles Dernieres and then in 1995 on Timbalier and East Timbalier Islands in their

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efforts to inventory coastal sand dunes of Louisiana. Data was collected along

thirteen transects on the Isles Dernieres and eight transects on Timbalier and East

Timbalier Islands.

Common beach and dune species included:, smooth cordgrass (Spartina

alterniflora), bitter panicgrass (Panicum amarum), eastern baccharis (Baccharis

halimifolia), seaoxeye, coastal dropseed, Cyperus sp., Jesuits bark (Iva frutescens),

beach morning glory (Ipomoea stolonifera), seashore paspalum (Paspalum

vaginatum), annual seepseed (Suaeda linearus), seaside goldenrod (Solidago

sempervirens), Sabatia stellaris, marsh fimbry (Fimbristylis castaneae), Olneys

bulrush (Scirpus olneyi), and shoreline seapurslane (Sesuvium portulacastrum)

(Ritchie et al. 1989 and Ritchie et al. 1995).

Typical mangrove-saltmarsh species included Batis maritima, Salicornia bigelovii.

Avicennia germinans, and Spartina alterniflora (Ritchie et al. 1989 and Ritchie et

al. 1995).

4.2.6.2.2 Existing Conditions

The vegetation species composition in existence today is similar to that reported by

Ritchie et al. 1989 and 1995 and Visser and Peterson (1995).

Barrier shorelines and associated back marsh areas are dynamic areas with

considerable spatial and temporal variation in plant species distribution. The

Study Area is subjected to varying degrees of natural and human disturbance.

Vegetation is one of the most important factors in trapping and retaining sediments

in the barrier shoreline system. The zones or communities of barrier island

vegetation and the extent of their diversity are related to elevation, degree of

exposure to salt spray, and storm events that cause overwash. These zones often

intergrade with each other: beach pioneer zone  frontier zone  dune  barrier

grasslands  salt flats  salt marsh  intertidal mud flats (after Ritchie et al.

1990 and 1995). The species found in the Terrebonne Basin (Table 4-6) are similar

to those recoded in the adjacent Barataria Basin by Ritchie et al. (1990); and Ritchie

et al. (1995).

Vegetation contributes to the stability of barrier islands. Plant colonies trap and

retain suspended sediment (those essential for platform accretion and dune

formation), and protect those newly deposited material from erosion. Vegetation

also contributes to soil structure, nutrients, and trophic level food supply through

their decomposition, and subsequent accumulation of organic matter (detrital

material). In addition to the structural and nourishment benefits, vegetation also

provides habitat function and serves as an indirect indicator of wildlife and fisheries

species vigor and condition (USDA, 2005). Similarly, the types and productivity of

vegetative communities are controlled by the factors that influence coastal land

loss, and their ability to adapt to those conditions. The loss of wetlands has and

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continues to impact all vegetative community types, from the barrier islands,

headlands, and salt marshes at the coastal shore, to the interior fresh marshes,

swamps and bottomland forests (USACE, 2004a).

Marsh vegetation within coastal Louisiana includes those associated with fresh,

brackish and saline conditions. Salt marsh communities (those that are common

and fundamental to barrier islands) are characterized by some degree of tidal

inundation, saline substrates, waterlogged soils, and salt-tolerant vegetation. These

communities develop in the lee of the barrier islands, providing lateral support to

the beach, and essential nursery grounds for finfish and shellfish (USEPA, 1997a).

Rare, Unique, and Imperiled Vegetative Communities

The Louisiana Natural Heritage Program describes imperiled vegetative

communities occurring in the Study Area including: coastal mangrove thicket,

coastal dune grassland, and coastal dune shrub thicket. These communities are

nestled within the broader vegetative habitats and are important in that they

contribute to the extensive diversity of the coastal ecosystem, enhance its

productivity, and are essential to the stability of the bionetwork.

Table 4-6. Vegetation of Study Area [source: based on site visits and after

Ritchie et al. (1990); and Ritchie et al. (1995)]

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4.2.6.3 Upland Vegetation

4.2.6.3.1 Historic Conditions

Upland vegetation was not historically present in the Study Area.

4.2.6.3.2 Existing Conditions

Upland vegetation is not currently present in the Study Area.

4.2.6.4 Submerged Aquatic Vegetation

4.2.6.4.1 Historic Conditions

Based on a review of the U.S. Fish and Wildlife Service National Wetland Inventory

Map data, which includes a historic wetlands map information layer, there is no

indication that submerged aquatic vegetation historically existed in the Study Area

(U.S. Fish and Wildlife Service 2009).

4.2.6.4.2 Existing Conditions

Based on a review of the U.S. Fish and Wildlife Service National Wetland Inventory

Map data and site visits, no submerged aquatic vegetation was observed and/or

known to exist in the Study Area (U.S. Fish and Wildlife Service 2009).

4.2.6.5 Invasive Species  Vegetation

4.2.6.5.1 Historic Conditions

Historical information regarding the presence of invasive species in the Study Area

has not been found.

4.2.6.5.2 Existing Conditions

Although some potentially invasive species [Chinese tallow (Triadica sebifera) and

cogongrass (Imperata cylindrica)] are actively infesting Gulf coast wetlands and

forests, no problems caused by encroachment of these species have been reported on

Louisianas barrier islands (personal communications C. Steyer, NRCS; K.

Bahlinger, LDNR; M. Hester, LSUNO; M. Materne, LSU Agcenter; I. Mendelssohn,

LSU; C. Reid, LDWF; J. Visser, LSU). This is likely due to the extreme

environmental conditions, such as higher salinities, shifting substrates, and

frequent storm disturbance that severely limit suitability of the habitat for

colonization.

4.2.7 Wildlife and Habitat

4.2.7.1 Historic Conditions

This resource is institutionally significant because of the National Environmental

Policy Act of 1969; the Coastal Zone Management Act; Estuary Protection Act; the

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Fish and Wildlife Coordination Act of 1958, as amended; the Migratory Bird

Conservation Act of 1929, as amended; the Migratory Bird Treaty Act of 1918; the

Endangered Species Act of 1973 (ESA), as amended; the Fish and Wildlife

Conservation Act of 1980; the North American Wetlands Conservation Act;

Executive Order 13186 Migratory Bird Habitat Protection; Migratory Bird

Conservation Act; and the Marine Mammal Protection Act. Wildlife resources are

technically significant because they are a critical element of the coastal barrier

ecosystem, they are an important indicator of the health of coastal habitats, and

many wildlife species are important recreational and commercial resources.

Wildlife resources are publicly significant because of the high priority that the

public places on their aesthetic, recreational, and commercial value.

Wildlife distributions in barrier systems are influenced by landforms, climate,

salinity, tides, vegetation, other animals, and human activities (Day et al. 1989).

Wildlife, their general habits and habitat requirements potentially occurring in the

Study Area are described in the following: Conner and Day (1987), Abernethy

(1987), Condrey et al. (1995), Louisiana Coastal Wetlands Conservation and

Restoration Task Force and the Wetlands Conservation and Restoration Authority

(1999) (hereinafter referred to as the Coast 2050 Report (1999).

4.2.7.2 Existing Conditions

4.2.7.2.1 Amphibians and Reptiles

Little if any information exists regarding the population status of amphibians and

reptiles in the Study Area. Condrey et al. (1995) indicates that virtually nothing is

known about the populations of seven species of salamanders, 13 species of frogs

and toads reportedly occurring in the Barataria-Terrebonne National Estuary.

With the exception of American alligator (Alligator mississippiensis) harvest data,

there is a general lack of data on the status and trends of most of the reptiles

worldwide (Gibbons et al. 1999) as well as those species that may inhabit the Study

Area. Generally, direct harvest and loss and degradation of habitat have resulted

in the depletion of all the Terrebonne Basins commercially important reptiles

(Condrey et al.1995). The herpetofauna typically found in the Gulf salt marsh

environments are the Gulf salt marsh snake (Nerodia clarkii clarkia), the Gulf coast

toad (Bufo valliceps), and the diamondback terrapin (Malaclemys terrapin)

(Abernethy (1987). Condrey et al. (1995) reports that coastal erosion and barrier

island retreat directly threatens the diamond-backed terrapin (Malaclemys

terrapin).

4.2.7.2.2 Mammals

Other than fur harvest records, little is known about the status and trends of

mammals throughout the Barataria-Terrebonne Basin (Condrey et al. 1995). The

interagency Coast 2050 Report (1999) characterizes the current population status,

population trends since 1985, and population projections to 2050 for several

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furbearers, (including nutria, muskrat, mink, river otter, and raccoon) and three

game mammals (rabbit, squirrel, and deer) for various habitat types throughout the

Study Area. Deer and squirrel have not been historically present or are no longer

present throughout the entire Study Area. Rabbit populations have been steady

since 1985, but only in the Caminada Headland area. Furbearer population trends

since 1985 are reportedly decreasing throughout the entire Study Area.

4.2.7.2.3 Avifauana

The Study Area is located within the Mississippi River migration flyway (Bellrose,

1980) that is a major bird migration corridor within North America. The Study

Area is an important staging area for migrating neotropical passerines. Abernethy

(1987) reports 411 species of birds inhabit the Barataria-Terrebonne estuary. The

decline in populations of neotropical passerine migrants is a serious conservation

problem; one that may be linked to the availability of suitable en route habitat

where energy reserves critical to successful migration can be replenished rapidly

and safely (Moore et al. 1990). The Study Area is also important to shorebirds and

waterfowl, as well as providing important wintering and breeding habitat for many

different species of seabirds, shorebirds, wading birds, waterfowl, raptors, and

songbirds (Lowery, 1974; Helmers, 1992; Chabreck et al., 1989; Martin and Lester,

1991; Condrey et al., 1995; BTNEP, 1996; Coast 2050 Report, 1999). Martin and

Lester (1991) and Visser and Peterson (1994) provide information and maps

regarding colonial nesting seabirds and wading bird populations in the Study Area.

Condrey et al. (1995) cites 353 species of birds occurring throughout the BaratariaTerrebonne estuary. Condrey et al. (1995) summarize the historical trends and

causes for change, habitat requirements, and major factors affecting selected groups

of avifauna species occurring throughout the Barataria-Terrebonne estuary system.

According to a survey done by Louisiana Department of Wildlife and Fisheries in

2008, approximately 44,771 nesting pairs of wading birds and seabirds were

observed throughout the Isle Dernieres reach. Louisiana Department of Wildlife

and Fisheries completed a Bird Colony Survey in 2006 for Timbalier and

Terrebonne Bay areas. Approximately 1,265 wading bird and seabird colonies

inhabit along East Timbalier Island and Bayou Lafourche (Personal

Communication Mike Carlos LDWF, 2009). Louisiana coastal wetlands provide

essential stopover habitat for neotropical migratory birds on their annual migration

route. Without stopover sites to provide adequate food supply for the quick

replenishment of fat reserves, shelter from predators, and water for rehydration,

migratory birds may be negatively affected. Continued losses of wintering habitat

and a better understanding of waterfowl requirements have led to increased

concern and interest in the conservation of breeding, migration, and wintering

habitats (USACE, 2004).

4.2.7.2.4 Invasive Wildlife Species

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The nutria (Myocastor coypus) and the Norway rat (Rattus norvegicus) are the

primary invasive mammalian species that could occur throughout the Study Area

(http://invasive.btnep.org/). However, the nutria is typically found in the freshwater

swamps and marshes of the Barataria-Terrebonne estuary system which are located

outside of the Study Area (Condrey et al., 1995). The monk parakeet (Myiopsitta

monachus), Eurasian collared-dove (Streptopelia decaocto), English sparrow (Passer

domesticus), European Starling (Sturnus vulgaris), and cattle egret (Bubulcus ibis)

are all potential invasive avian species that could be found in the Study Area

(http://invasive.btnep.org/default.asp?id=51).

4.2.8 Aquatic Resources

4.2.8.1 Plankton

This resource is institutionally significant because of the National Environmental

Policy Act of 1969, the Coastal Zone Management Act, and the Estuary Protection

Act. This resource is technically significant because plankton provide a major,

direct food source for animals in the water column and in the sediments; plankton

are responsible for at least 40% of the photosynthesis occurring on the earth;

plankton are important for their role in nutrient cycling; plankton productivity is a

major source of primary food-energy for most estuarine systems throughout the

world; and phytoplankton production is the major source of autochthonous organic

matter in most estuarine ecosystems (Day et al., 1989). This resource is publicly

significant because plankton form the lowest trophic food level for many larger

organisms important to commercial and recreational fishing. In addition, there is a

public health concern with noxious plankton blooms (red and brown tides) that

produce toxins, and large-scale blooms can lead to hypoxic conditions, which can

result in fish kills.

4.2.8.1.1 Historic Conditions

Plankton communities serve an important role in the coastal waters of Louisiana.

Phytoplanktons are the primary producers of the water column, and form the base

of the estuarine food web. Zooplanktons provide the trophic link between the

phytoplankton and the intermediate level consumers such as aquatic invertebrates,

larval fish, and smaller forage fish species (Day et al., 1989). Microzooplanktons

appear to be important consumers of bacterioplankton, which are typically

enumerated by culture and microscopic techniques. Culture techniques are

selective and invariably underestimate bacterial densities (Day et al., 1989). The

Cooperative Gulf of Mexico Estuarine Inventory and Study, Louisiana, prepared by

the Louisiana Wildlife and Fisheries Commission in 1971 provides a summary of

plankton across the coastal estuaries of Louisiana in the late 1960s (Perret et al.,

1971). The dominant member of the zooplankton community throughout that study

was the copepod Acartia tonsa. The greatest concentrations of zooplankton were

encountered in Breton Sound. The lowest concentrations were encountered in

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Chandeleur Sound and Lake Borgne east of the Mississippi River, Lakes Barre and

Raccourci, and Terrebonne and Timbalier Bays. Species diversity was greatest in

the Breton Sound and Mississippi River, East Bay, Garden Island Bay, and West

Bay areas.

Historically, salinity appears to be the chief controlling factor in the number of

species present, while temperature, competition, and predation control the number

of individuals present (Day et al., 1989). In addition, the abundance of certain

zooplankton may be indicative of good fishing areas. While some zooplanktons are

euryhaline, others have distinct salinity preferences (Day et al., 1989). Therefore,

introduction of river water into estuarine systems may have dramatic short-term

impacts on plankton populations in adjacent coastal waters (Hawes and Perry,

1978).

4.2.8.1.2 Existing Conditions

Plankton is composed of three groups: the bacterioplankton, phytoplankton, and

zooplankton (Knox 2001). Plankton communities serve several important roles in

the coastal waters of Louisiana. Bacterioplankton are primarily decompsers;

phytoplankton are the primary producers of the water column, and form the base of

the estuarine food web; zooplankton provide the trophic link between the

phytoplankton and the intermediate level consumers such as aquatic invertebrates,

larval fish, and smaller forage fish species (Day et al. 1989). Most of the fish and

other nektonic species are part of the planktonic community only for the early

stages of their life cycles (Thompson and Forman 1987).

Phytoplanktons are single-cell algae that drift with the motion of water. The

dominant groups are diatoms and dinoflagellates; other important groups include

cryptophytes, chlorophytes (green algae), and chrysophytes (blue-green algae).

Phytoplankton productivity is a major source of primary food-energy for most

estuarine ecosystems throughout the world (Day et al. 1989). Species composition

of a given phytoplankton community is a function of various environmental factors

including salinity, turbidity, nutrients, turbulence, and depth (Day et al. 1989).

Zooplankton are faunal components of the plankton, including small crustaceans

such as copepods, ostracods, euphausiids, and amphipods; the jellyfishes and

siphonophores; worms, mollusks such as pteropods and heteropods; and the egg and

larval stages of the majority of benthic and nektonic animals (Rounsefell 1975).

Zooplankton are weakly swimming animals comprised of two broad categories:

holoplankton, which are planktonic species as adults, and meroplankton, which are

organisms that occur in the plankton during early life stages before becoming

benthic or nektonic (most common are immature forms of benthic invertebrates).

Zooplanktons serve as food for a variety of estuarine consumers, but also are

important for their role in nutrient cycling.

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Within the nearby Barataria Basin, the zooplankton community is dominated by

copepods of the genus Acartia (Gillespie 1971, 1978; Bouchard and Turner 1976;

Conner and Day 1987). Perret et al. (1971) indicates the dominant member of the

zooplankton community throughout Louisiana was the copepod Acartia tonsa.

Zoeae (a larval stage in some crustaceans) can make up a large component of the

meroplankton. Fish larvae (e.g., Brevoortia patronus, Anchoa mitchilli, Menidia

beryllina and Mugil cephalus) and fish eggs were found throughout the Barataria

Basin (Conner and Day 1987). Zooplankton in Louisiana waters are in some cases

dominated by zoeae of the mud crab Rithropanopeus harrisii. While some

zooplanktons are euryhaline, others have distinct salinity preferences. Historically,

salinity appears to be the chief controlling factor in the number of species present,

while temperature, competition, and predation control the number of individuals

present (Perret et al. 1971). In addition, the abundance of certain zooplankton may

be indicative of good fishing areas. Conner and Day (1987) indicate that in most

estuaries, zooplankton feed on phytoplankton or ingest detritus or both. Most

zooplankters are filter feeders and the suspended detritus particulate material in

the waters of Barataria is probably a major food source.

Biological factors such as predation by nekton and ctenophores, duration of the

larval stages of meroplankton, and changes in the aquatic environment brought by

the zooplankton populations themselves are important biological factors in the

regulation of zooplankton densities (Bouchard and Turner 1976; Conner and Day

1987). Bouchard and Turner (1976) found that salinity largely influenced the

distribution of zooplankton. Gillespie (1978) found spring zooplankton peaks were

related to temperature. Conner and Day (1987) identified the following factors

affecting zooplankton populations: tidal flushing, inflow of freshwater carrying

organic detritus, river discharge, water depth, tidal changes, turbidity, and

dissolved oxygen.

4.2.8.2 Benthic

4.2.8.2.1 Historic Conditions

These resources are institutionally significant because of the NEPA of 1969; the

Coastal Zone Management Act; and the Estuary Protection Act. These resources

are technically significant because the bottom of an estuary regulates or modifies

most physical, chemical, geological, and biological processes throughout the entire

estuarine system via what is called a benthic effect. Benthic animals are directly

or indirectly involved in most physical and chemical processes that occur in

estuaries (Day et al., 1989). Benthic resources are publicly significant because

members of the epibenthic community (e.g., oysters, mussels, etc.) provide

commercial and recreational fisheries as well as creating oyster reef habitats used

by many marine and estuarine organisms.

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Benthic community structure is not static; it provides a residence for many sessile,

burrowing, crawling, and even swimming organisms. The benthic community is a

storehouse of organic matter and inorganic nutrients, as well as a site for many

vital chemical exchanges and physical interactions. Day et al. (1989) describe the

functional groups of estuarine benthic organisms. These groups include:

macrobenthic (e.g., molluscs, polychaetes, decapods); microbenthic (e.g., protozoa);

meiobenthic (e.g., nematodes, harpacticoid copepods, tubillaria), epibenthic; infauna

(e.g., most bivalves); interstitial fauna (e.g., beach meiofauna, tardigrades);

suspension-feeders (e.g., bryozoans and many bivalves); filter-feeders (e.g.,

poriferans, tunicates, bivalves); nonselective deposit feeders (e.g., gastropods);

selective deposit feeders (e.g., nematodes, sand dollars, fiddler crabs); raporial

feeders and predators (e.g., star fish and gastropod drills); and parasites and

commensuals (e.g., parasitic flatworms and copepods, pea crabs).

The bottom estuarine substrate or benthic zone regulates or modifies most physical,

chemical, geological, and biological processes throughout the entire estuarine

system via what is commonly called a benthic effect (Day et al., 1989). Within a

salt marsh, less than 10% of the above-ground primary production of the salt marsh

is grazed by aerial consumers. Most plant biomass dies and decays and its energy is

processed through the detrital pathway. The major consumer groups of the benthic

habitat include: bacteria and fungi, microalgae, meiofauna, and microfauna (Mitsch

and Gosselink 1993).

According to Mitsch and Gosselink (1993), the salt marsh is a major producer of

detritus for both the salt marsh system and the adjacent estuary. Mitsch and

Gosselink (1993) point out that the detritus material exported from the marsh is

more important to the estuary than the phytoplankton-based production in the

estuary. Detritus export and the shelter found along marsh edges make salt

marshes important nursery areas for many commercially important fish and

shellfish. Salt marshes have been shown at times to be both sources and sinks of

nutrients, particularly nitrogen.

Baker et al. (1981) sampled the Louisiana Continental Shelf (LCS), including Ship

Shoal, to determine the ecological effects of petroleum production platforms in the

central Gulf of Mexico. Results indicate that the benthic communities of the Ship

Shoal varied from that found throughout the LCS (Table 4-7).

Table 4-7. Percent taxonomic composition of meiofauna, macroinfauna

and macroepifauna from the Baker et al. (1981) study

Category and Taxa Ship Shoal

(%)

Louisiana Continental Shelf

(%)

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Meiofauna

Formineferia 0.2 55.3

Nematoda 97.0 34.7

Macroinfauna

Polychaeta 62.6 69.0

Macroepifauna

Osteichytes 69.3 32.8

Decapoda 30.7 25.7

4.2.8.2.2 Existing Conditions

Baustian (2005) sampled the benthic infauna over a broad area of hypoxia off the

central coast of Louisiana. The extent of the sampled area consisted of three zones,

the inshore zone, hypoxia zone, and offshore zone. The inshore zone coincides with

the LCA TBBSR Study Area. Baustian reports that the infauna were composed

mostly of polychaetes, but molluscs, ecninoderms and crustaceans were abundant in

most areas. In the inshore areas, the Paraprionospio pinnata and Prionospio

pygmaea, Mulinia lateralis and Tellina versicolor, Hemipholis elongate, and the

Oxyurostylis smithi were the abundant spionids, mollusks, echinoderms, and

crustaceans respectively (Figure 4-10). This assemblage is typical of soft bottom,

mesohaline (5 ppt 18 ppt) communities throughout the northern Gulf of Mexico.

Offshore sand shoals (e.g., Ship Shoal) and the nearshore sand bodies represent

potential sources for the millions of tons of sand sediment that would be necessary

for coastal restoration. With its extensive oil and gas activities, the benthic

resources on Ship Shoal have been extensively studied. The following is a summary

of the benthic resources on Ship Shoal provided by the MMS (personal

communication Barry Drucker, Minerals Management, 2002).

Ship Shoal benthic communities are threatened by two natural environmental

perturbations that occur on the Louisiana continental shelf (LCS), anoxic to hypoxic

bottom conditions and tropical cyclones. The change from anoxic to hypoxic

conditions occurs annually with inconsistent intensities and ranges (Rabalais et al.

1993). On average, one tropical cyclone visits the LCS once every four years, which

can vary in intensity (Stone 2000). It takes from one to two years for the benthic

communities to recover from either of these types of events (Baker et al. 1981).

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Figure 4-10. Percent of individuals by major taxonomic group for summer

samples. (Baustian, 2005)

Results from the Southwest Research Institute study indicated that the prevailing

macroepifauna and demersal fish on Ship Shoal are in the taxa Osteichytes (69.3%)

and Decapoda (30.7%). Taxa Decapoda, although similar in taxonomic composition

to that found on the LCS, was lower in diversity on Ship Shoal. The taxa

Osteichytes was found to be particularly higher in taxonomic composition (69.3%) of

the total macroepifauna, but lower in diversity when compared to the entire LCS.

Shallower water depths such as those found on Ship Shoal were correlated to a

larger abundance of taxa Osteichytes and would explain the increased taxonomic

composition (Baker et al. 1981). The biomass of demersal fish on Ship Shoal was

found to be much higher than those of the LCS on average. The biomass on Ship

Shoal was recorded at 151.8 lbs/hr (68.7 kg/hr) in comparison to an average of 43.3

pounds/hr (19.6 kg/hour) throughout the LCS (Baker et al. 1981). These results

suggest that Ship Shoal is an extremely productive ground for demersal fish in the

context of the LCS.

The diversity, taxonomic composition, and presence of opportunistic species indicate

that the fauna residing on Ship Shoal and the LCS are stressed. This slightly

depressed state may remain constant because of the periodic perturbations and

recovery time needed by benthic communities. Even though the benthic

communities of the LCS are stressed, they still resemble the assemblages of similar

environments. Results from the Southwest Research Study found that the benthic

assemblages on the LCS and Ship Shoal were similar to those found offshore of

Texas and the eastern United States despite their depressed state (Baker et al.

1981; Vittor 1987).

In an effort to gain a better understanding of the role of Ship Shoal plays in

Louisianas coastal ecosystem and to address the potential effects of sand mining on

the benthic community, Stone et al. (2004) conducted extensive field surveys of the

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benthic community. Primary producers, meiofauna, and macrobenthos were

included in the investigation.

They examined the origin, composition, and spatial and temporal distribution of

sediment algae on Ship Shoal. Seasonal variability ranged from < 10 to 50 mg/m2 in

2005 and from 21 to 53 mg/m2 in 2006. Sediment algal biomass was highest in the

spring and summer and pigment analysis indicated that sedimentary algae were

predominantly diatoms across all sample stations and for all seasons. Further

analysis of sediment samples revealed that the diatoms were primarily benthic with

only a minor fraction being settled phytoplankton. Comparisons of pigments from

the sediment and bottom water, suggested a weak exchange of benthic and pelagic

algae and the high benthic algal biomass. The report concluded that the high

benthic algal biomass strongly suggests that benthic primary producers contribute

to the food web on Ship Shoal.

Stone et al. (2004) reported that macrobenthic community at Ship Shoal contains a

significant number of macroinvertebrate species not previously reported on the

Louisiana continental shelf and that the shoal may serve as a source pool for

recruitment of benthic invertebrates to surrounding areas impacted by seasonal

hypoxia. They also reported high-biomass and high-diversity assemblage of

macroinfauna compared to nearby locations and suggested that it may be a

diversity hotspot as well as an important hypoxia refuge for macroinfauna

sensitive to low dissolved oxygen concentrations reported for the surrounding area.

Seasonal data indicated a steady but large decline between spring, summer, and

autumn which was likely attributed to predation by high concentrations of blue

crabs (Callinectes saidus).

4.2.9 Fisheries

Fishery resources are institutionally significant because of the Fish and Wildlife

Coordination Act of 1958, as amended; the Endangered Species Act of 1973; the

Magnuson-Stevens Fishery Conservation and Management Act of 1976, as amended

(Magnuson-Stevens Act); the Magnuson-Stevens Act Reauthorization of 2006; the

Coastal Zone Management Act; and the Estuary Protection Act. Fishery resources

are technically significant because: they are a critical element of many valuable

freshwater and marine habitats; they are indicators of the health of various

freshwater and marine habitats; and many species are commercially important.

Fishery resources are publicly significant because of the high priority placed on

their aesthetic, recreational, and commercial value.

4.2.9.1 Historic Conditions

The abundance of coastal wetlands, specifically those that provide habitat and

support during vital stages of primary and commercial fish life cycles, have

established Louisianas estuaries as the most productive in the Nation (USACE,

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2004a). Central to this productivity is the Barataria-Terrebonne estuarine complex,

which generates more brown and white shrimp than any other zone in the state,

and supports approximately 20% of the estuarine-dependent fishery resources of the

United States (USEPA, 1997a). The high levels of fish productivity within the

Barataria-Terrebonne estuary can be attributed to its current erosional barrier

island phase within the deltaic cycle. Plant and fish diversity and productivity are

highest during the degradation phase due to significant increases in essential

edge habitats. However, as the interior and barrier island marshes continue to

degrade towards open water and/or shoal dominated systems, biological diversity

and productivity decline (USACE, 2004a).

4.2.9.2 Existing Conditions

4.2.9.2.1 Isles Dernieres Reach

The Isles Dernieres and its back-bay estuaries and wetlands provide critical habitat

for one of the world's most productive commercial fisheries. The islands provide

habitat protection, regulate salinity levels, absorb wave energy, and reduce the tidal

prism from the GOM (USEPA, 1997a). Fish assemblages and related habitat on the

islands can be placed into three primary groups: (1) open surf zone beach, (2) back

island low-energy zones, and (3) intra-island ponds and streams (USEPA, 1997a).

As of 2009, there were three existing oyster leases in the Old Camp Pass area, and

two pending applications in the southeast Old Camp Pass area of Trinity Island.

There were two additional applications for East Island, one in a back bay near the

west end of the island (this application contains no expiration date), and the second

was on the recurved spit at the east end (LDWF, 2009).

4.2.9.2.2 Timbalier Reach

Surf zones, ponds, lagoons, creeks, inlets, and back-island marshes are all aquatic

habitats located on or near the Timbalier islands (USDC, 1998). These island

features are typically used by many different fish species for nursery, foraging, and

predator habitat. The characteristic species found near the islands are similar to

those found at the Isles Dernieres and include Micropogonias undulates (Atlantic

croaker), Pogonias cromis (black drum), Callinectes sapidus (blue crab),

Farfantepenaeus aztecus (brown shrimp), Brevoortia patronus (Gulf menhaden),

Sciaenops ocellatus (red drum), Cynoscion arenarius (sand seatrout), Cynoscion

nebulosus (spotted seatrout), Scomberomorus maculatus (Spanish mackerel),

Paralichthys lethostigma (southern flounder), Mugil cephalus (striped mullet), and

Litopenaeus setiferus (white shrimp). A U.S. Department of Commerce

Environmental Assessment of East Timbalier Island Restoration Project report

(USDC, 1998) identified a survey by Williams (1988) that also documented nekton

assemblages of adult hardhead catfish, squid, and blue crab communities in

deepwater tidal creek and channels within East Timbalier Island. The majority of

the nekton species that spawn offshore in the GOM, utilize the Timbalier Bay

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habitat as larvae or young juveniles, and then return to the GOM as adults. The

USDC report also identified several fisheries studies (Zimmerman, 1988;

Thompson, 1988; and Williams 1988) that indicate the nekton species composition

found near the barrier islands closely match those identified within the mainland

marshes (USDC, 1998).

4.2.9.3 Implications

Most finfish and shellfish in the Barataria-Terrebonne estuaries show decreasing

population trends, with only the Spanish mackerel populations believed to be

significantly increasing (Coast 2050). These declines in population may be linked to

the extreme degradation of coastal marsh and reductions in the barrier islands

extent. Continued loss of barrier islands would expose large areas of estuary and

wetlands, and convert back island bays to gulf waters, negatively impacting coastal

infrastructure, fish, oyster, and other biological resources (USEPA, 1997a).

4.2.9.4 Finfish

The Timbalier and Isles Dernieres barrier island wetlands, flats, and subtidal

habitat provide unique nursery, foraging, and spawning habitat for numerous

marine and estuarine species of commercial and recreational importance (personal

communication NMFS, February 11, 2009). Coastal wetlands, such as occur

throughout the Study Area, produce nutrients and detritus that contribute to the

overall productivity of the estuary aquatic food web (Chapter 19 Coastal Systems in

2005 "Ecosystems and Human Well-Being: Current State and Trends: Findings of

the Condition and Trends Working Group (Millennium Ecosystem Assessment

Series)"). The Study Area is utilized by distinct groups of fish and crustaceans that

exhibit a preference for barrier island habitats over mainland habitats or are

dependent on these habitats as transients during portions of their life history for

foraging and predator refugia (Williams 1998). Common surf zone species include

gulf menhaden (Brevoortia patronus), spot (Leiostomus xanthurus), striped mullet

(Mugil cephalus), southern kingfish (Menticirrhus americanus), anchovies (Anchoa

spp.), scaled sardine (Harengula jaguana), Florida pompano (Trachinotus

carolinus), Atlantic bumper (Chloroscombrus chrysurus), spotfin mojarra

(Eucinostomus argenteus), and rough silverside (Membras martinica). The surf zone

temporarily is used by larval and juvenile life stages of some of these species

awaiting transport to back-barrier, bay, or mainland habitats. Barrier island flats

typically are used by white mullet (Mugil curema), longnose killifish (Fundulus

similis), darter goby (Ctenogobius boleosoma), and inland silversides (Menidia

beryllina). Marsh edge and interior creeks are used by brown shrimp

(Farfantepenaeus aztecus), white shrimp (Litopeneaus setiferus), Atlantic croaker

(Micropogonias undulatus), spotted seatrout (Cynoscion nebulosus), sheepshead

minnow (Cyprinodon variegatus), killifish, and sand seatrout (Cynoscion arenarius),

some of which are constituents of assemblages that use the other island aquatic

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habitats (Foreman 1968; Zimmerman 1988). Additionally, shallow, back-bay areas

are inhabitated by American oysters (Crassostrea virginica).

Economically important fish species such as spotted seatrout, red drum (Sciaenops

ocellatus), black drum (Pogonias cromis), and southern flounder (Paralichthys

lethostigma) use the barrier island habitats (e.g., shorelines and passes) for foraging

areas, nursery habitat, and staging areas during spawning or associated migratory

aggregations (Saucier and Baltz 1993). Additionally, yearlings of red drum and

mangrove snapper (Lutjanus griseus) have a high affinity for quiescent intra-island

creeks and ponds in the post larval early juvenile stages (Thompson 1988).

The nearest port, at Dulac-Chauvin, Louisiana, reported commercial fisheries

landings in 2007 at 23.5 million pounds with a dockside value of 35.5 million dollars

(NMFS, 2008). Based in part on its high commercial and ecological productivity, the

Terrebonne basin was nominated for participation in the National Estuary Program

in 1989 in recognition of its significance for ecological and economic sustainability of

estuarine resources (http://www.btnep.org/). Abundant harvested species include

brown shrimp, white shrimp, sand seatrout, black drum, southern flounder, blue

crab (Callinectes sapidus), gulf menhaden, and anchovies (Patillo et al. 1997).

Important forage species in the area bays and mainland marshes include many of

the species associated with barrier islands (Patillo et al. 1997; Zimmerman 1988).

Other species that occur in the Study Area during some portion of their life history

include the ecologically important grass shrimp (Palaemonetes spp.) (Pattillo et al.

1997). Many other non-game species of finfish and shellfish are important links in

the food chain to commercially and recreationally harvested species. Study area

wetlands produce nutrients and detritus that contribute to the overall productivity

of the Terrebonne estuary aquatic food web.

4.2.9.5 Shrimp

Gulf region landings of shrimp were the nations largest with 176.6 million pounds

and 76% of the national total in 2007. In Louisiana, a total of 44.8 million pounds of

brown and 63.4 million pounds of white shrimp were landed in 2007, with a value of

$43.3 million and $94.1 million, respectively (NMFS, 2008).

Within the BTES, brown shrimp are consistently the most numerous shellfish

landings followed by white shrimp, blue crab, and oyster (Baltz et al. 1993). Black

drum, striped or black mullet, blue crab, American oyster, and brown shrimp have

shown stable trends since 1985. Only white shrimp have displayed increasing

fishery landing trends since 1985. However, the connection between fishery

landings and salt marsh habitat loss is not clear (Baltz et al. 1993). One hypothesis

is that marsh edge (i.e., perimeter) is the critical habitat for many species and that

the nursery function will not decline and result in reduced landings until the

quantity of marsh edge begins to decline (USACE, 2009).

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The offshore borrow site at Ship Shoal and the nearshore borrow sites support

white and brown shrimp and spotted seatrout fisheries. These species are major

components of the Ship Shoal ecosystem. White and brown shrimp are

opportunistic benthic-feeding omnivores. Spotted seatrout are important predators

on white and brown shrimp (USACE, 2009).

4.2.9.6 Blue Crab

About eight species of portunid (swimming) crabs use the coastal and estuarine

areas in the Gulf of Mexico. Blue crabs are the only species, however, that is located

throughout the Gulf that comprises a substantial fishery. They occur on a variety of

bottom types in fresh, estuarine, and shallow offshore waters. Spawning grounds

are areas of high salinity such as saline marshes and nearshore waters.

Louisiana is the leading blue crab producer in the U.S., producing 32% of the

nations total in 2007 (NMFS, 2008). Statewide, a total of 44.6 million pounds of

blue crab were landed in 2007, with a value of $34.3 million (NMFS, 2008).

According to a report by McKenzie et al. on the socioeconomic status and trends of

the Barataria-Terrebonne Estuary System (BTES; 1995), from 1979-1992 the BTES

accounted for more than 70% of the Statewide totals of commercial crab landings.

A U.S. Department of Commerce environmental assessment of East Timbalier

Island Restoration Project report (USDC, 1998) identified a survey by Williams

(1988) that also documented blue crab communities in deepwater tidal creek and

channels within East Timbalier Island. The NMFS (personal communication NMFS

February 21, 2009) indicate that research of Ship Shoal, a potential offshore borrow

site, suggests there are more diverse and productive macrofauna on the slopes of

the shoal and that the shoal may be spawning habitat for blue crab.

4.2.9.7 Oyster

The American oyster is indigenous to coastal Louisiana, and provides a rich

ecological and commercial resource (Figure 4-11). Salinity plays a key role in oyster

sustainability. Adult oyster can tolerate salinities from 0 to 42 ppt, but the optimal

range is 5-15 ppt. Fresher waters fail to support biological function, and more

saline waters promote disease and predation. Oysters grow faster in areas with

fluctuating salinities within their normal ranges, compared to constant salinity

(Pierce and Conover, 1954). Adult oysters are more prone to impacts from changes

in water quality than commercially harvested fishes and crustaceans because they

are sessile, and cannot relocate in response to changes in water quality parameters.

The importance of Barataria-Terrebonne estuary oyster productivity and supply

parallels that of the nekton species. In 2006, Gulf Crassostrea virginica (eastern

oyster) fisheries were estimated to account for nearly 74% of the national total,

producing 19 million pounds of meat. The critical oyster habitats (oyster beds) in

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the Terrebonne Basin barrier island chain are typically located in the ponds and the

meandering of bayside marshes (NMFS, 2008).

Figure 4-11. Oyster lease map for the Isles Dernieres and Timbalier Reach

4.2.10 Essential Fish Habitat (EFH)

Fishery resources are institutionally significant because of the Fish and Wildlife

Coordination Act of 1958, as amended; the Endangered Species Act of 1973; the

Magnuson-Stevens Fishery Conservation and Management Act of 1976, as amended

(Magnuson-Stevens Act); the Coastal Zone Management Act; and the Estuary

Protection Act. Fishery resources are technically significant because they are a

critical element of many valuable freshwater and marine habitats, they are an

indicator of the health of various freshwater and marine habitats, and many fish

species are important commercial resources. Fisheries resources are publicly

significant because of the high priority that the public places on their esthetic,

recreational, and commercial value. Fishery resources in the Study Area include

marine and estuarine finfish and shellfish. Table 4-8 provides a summary of the

Magnuson-Stevens Fishery Conservation and Management Act designations of

essential fish habitat for Coastal Louisiana.

In order to offset declines in fish population and productivity, the MagnusonStevens Act of 1978 was established for the protection, conservation, and

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enhancement of Essential Fish Habitat (EFH). The Magnuson-Stevens Act, which

defines EFH as those waters and substrate necessary to fish for spawning,

breeding, feeding or growth to maturity, has been used to establish requirements

for fish species in the GOM (Table 4-8) (USACE, 2004b).

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Table 4-8. Summary of the Magnuson-Stevens Fishery Conservation and

Management Act - Designation of Essential Fish Habitat for Coastal

Louisiana* (USACE, 2004b)

4.2.10.1 Historic Conditions

Louisianas coastal estuaries are the most productive in the Nation. Louisiana has

historically been an important contributor to the Nations domestic fish and

shellfish production, and one of the primary contributors to the Nations food supply

for protein. Landings in 2007 for commercial fisheries in coastal Louisiana,

estimated at 951 million pounds, were the largest for any state in the contiguous

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U.S. and second only to Alaska (NMFS, 2008). These landings represent over 10% of

the total landings in the U.S., with a value of approximately $259.6 million.

4.2.10.2 Existing Conditions

By letter dated February 11, 2009, the NMFS indicated that, in addition to being

designated as essential fish habitat (EFH), the barrier island aquatic habitats

include ponds, lagoon, creeks, tidal channels, sand flats, surf zone, and back barrier

marshes. These island habitats and associated near shore water bodies in the Study

Area support fish and crustacean assemblages distinctly different from mainland

marshes. Examples of economically important marine fishery species in the Study

Area include striped mullet (Mugil cephalus), white mullet, Atlantic croaker

(Micropogonias undulates), spot, gulf menhaden, Florida pompano, spotted

seatrout, sand seatrout, southern flounder, black drum, and blue crab (Williams,

1998 as cited in personal communication NMFS, February 11, 2009). Some of these

species serve as prey for other Federally-managed fish species such as mackerels,

snappers, groupers, billfishes, and sharks.

Barrier islands provide three primary zones of habitats for shellfish and finfish.

These zones of habitats include the surf zone beach; back island low-energy zones

that are either sand flats or marsh; and intra-island ponds, lagoons, and meanders

(Britton and Morton, 1989). These habitats are characterized by specific physical

attributes and can have quite different fish fauna.

The offshore borrow site at Ship Shoal and the nearshore borrow sites support

white and brown shrimp and spotted seatrout fisheries. These species are major

components of the Ship Shoal ecosystem. White and brown shrimp are

opportunistic benthic-feeding omnivores.

Fishery resources in the Study Area include marine and estuarine finfish and

shellfish. Aquatic and tidally influenced habitats within the Study Area are

designated as EFH for various life stages for shrimp, red drum (Sciaenops

ocellatus), reef fish, and stone crab (Table 4-9) managed by the Gulf of Mexico

Fishery Management Council (GMFMC). In addition, the waterbodies and wetlands

in the Study Area provide nursery and foraging habitats supportive of a variety of

economically important fishery species, such as striped mullet, Atlantic croaker,

Gulf menhaden, spotted and sand seatrout, southern flounder, black drum, and blue

crab. Some of these species serve as prey for other fish species managed under the

Magnuson-Stevens Act by the GMFMC.

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Table 4-9. Essential Fish Habitat (EFH) for Various Life Stages for Shrimp,

Red Drum, Reef Fish, and Stone Crab (source: personal communication

NMFS February 21, 2009)

Species Life Stage System EFH

Brown Shrimp

Larvae Marine

<82 m depth; planktonic, sand/shell/soft

bottom, SAV, emergent marsh, oyster

reef

Juvenile Estuarine <18 m; SAV, sand/shell/soft bottom,

SAV, emergent marsh, oyster reef

White Shrimp Juvenile Estuarine <30 m; SAV, soft bottom, emergent

marsh

Pink Shrimp Juvenile Estuarine <65 m; sand/shell substrate

Gulf Stone Crab

Eggs Estuarine/Marine <18 m; sand/shell/soft bottom

Larvae/

Postlarvae Estuarine/Marine 18 m; planktonic/oyster reefs, soft

bottom

Juvenile Estuarine <18 m; sand/shell/soft bottom, oyster

reef

Red Drum

Larvae/

Postlarvae Estuarine All estuaries planktonic, SAV,sand/shell/soft bottom/ emergent marsh

Juvenile Estuarine/Marine

Gulf of Mexico <5 m west from Mobile

Bay; all estuaries SAV,

sand/shell/soft/hard bottom, emergent

marsh

Adults Marine/Estuarine

Gulf of Mexico 1-46 m west from Mobile

Bay; all estuaries SAV, pelagic,

sand/shell/soft/hard bottom, emergent

marsh

Lane Snapper

Larvae Estuarine/Marine 4-132 m; reefs, SAV

Juvenile Estuarine/Marine <20 m; SAV, mangrove, reefs,

sand/shell/soft bottom

Dog Snapper Juvenile Estuarine/Marine SAV, mangrove, emergent marsh

4.2.11 Threatened and Endangered Species

This resource is institutionally significant because of the Endangered Species Act of

1973, as amended, and the Marine Mammal Protection Act of 1972. Endangered

(E) and threatened (T) species are technically significant because the status of such

species provides an indication of the overall health of an ecosystem. These species

are publicly significant because of the desire of the public to protect them and their

habitats.

4.2.11.1 Historic Conditions

Factors regarding the historic and existing conditions for threatened and

endangered species in the Study Area principally stem from the alteration,

degradation, and loss of barrier habitats; and human disturbance. The continued

high rate of land loss throughout the Study Area over the past 100 years continues

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to reduce available coastland resources to threatened and endangered species. This

creates increased intra- and interspecific competition for rapidly depleting resources

between not only the various threatened and endangered species but also other

more numerous fauna. A more detailed description of the historic and existing

conditions for those threatened or endangered species that may be found in the

Study Area is provided in Appendix A.

The Endangered Species Act of 1973, as amended, requires the designation of

critical habitat for all threatened and endangered species. Critical habitat is habitat

essential for the conservation or recovery of an endangered or threatened species.

In the July, 2001 Final Rule (Federal Register, Vol. 66, No. 132), the USFWS

designated critical habitat for wintering populations of the endangered piping

plover (Figures 4-12 and 4-13).

4.2.11.2 Existing Conditions

Within the State of Louisiana there are 29 animal and 3 plant species (some with

critical habitats) under the jurisdiction of the USFWS and/or NMFS, presently

classified as threatened or endangered (Table 4-10). The USFWS and NMFS share

jurisdictional responsibility for sea turtles and the Gulf sturgeon. Of the animals

and plants under USFWS and/or NMFS jurisdiction, no plant species and only 7

animal species are potentially within the Study Area (including borrow areas).

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Table 4-10. Threatened and Endangered Species in LouisianaClassification Species Scientific Name Status Jurisdiction Found in Study Area?Mammals

Florida Panthera Felis concolor coryl Endangered USFWS No

Red Wolf1 Canis rufus Endangered USFWS NoWest Indian Manatee Trichechus manatus Endangered USFWS YesLouisiana Black Bear Ursus americanus luteolus Threatened USFWS No

Birds

Bachmans Warblerb Vermivora bachmanii Endangered USFWS No

Eskimo Curlew Numenius borealis Endangered USFWS NoIvory-billed Woodpeckera Campephilus principalis Endangered USFWS NoLeast Tern; interior population Sterna antillarum Endangered USFWS NoRed-cockaded Woodpecker Picoides borealis Endangered USFWS NoPiping Plover Charadrius melodus Threatened USFWS Yes

Reptiles

Hawksbill Sea Turtle Eretomchelys imbricata Endangered USFWS/NMFS Yes

Kemps (Atlantic) Ridley SeaTurtle

Lepidochelys kempii Endangered USFWS/NMFS Yes

Leatherback Sea Turtle Dermochelys coriacea Endangered USFWS/NMFS YesAmerican Alligatorc Alligator mississippiensis Threatened USFWS NoGopher Tortoise Gopherus polyphemus Threatened USFWS NoGreen Sea Turtle Chelonia mydas Threatened USFWS/NMFS YesLoggerhead Sea Turtle Caretta caretta Threatened USFWS/NMFS YesRinged Sawback Turtle Graptemys oculifera Threatened USFWS NoSnake, Louisiana Pine Pituophis ruthveni Candidated USFWS No

Fish

Pallid Sturgeon Scaphirhynchus albus Endangered USFWS No

Gulf Sturgeon Acipenser oxyrinchus desotoi Threatened USFWS/NMFS NoDusky Shark Carcharhinus obscurus Candidated NMFS NoSand Tiger Shark Odontaspis taurus Candidated NMFS NoNight Shark Carcharinus signatus Candidated NMFS No

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Classification Species Scientific Name Status Jurisdiction Found in Study Area?

Speckled hind Epinephelus drummondhayi Candidated NMFS NoSaltmarsh topminnow Fundulus jenkensi Candidated NMFS NoJewfish Epinephelus itajara Candidated NMFS NoWarsaw Grouper Epinephelus striatus Candidated NMFS No

Invertebrates

Mussel, Fat Pocketbook Potamilus capax Endangered USFWS No

Pink pearlymussel Mucket Lampsilis abrupta Endangered USFWS NoInflated (Alabama) Heelsplitter Potamilus inflatus Threatened USFWS NoLouisiana Pearlshell Margaritifera hembeli Threatened USFWS No

MarineMammals

Sperm Whale Physeter macrocephalus Endangered NMFS No

Sei Whale Balaenoptera borealis Endangered NMFS NoHumpback Whale Megaptera novaeangliae Endangered NMFS NoFinback Whale Balaenoptera physalus Endangered NMFS NoBlue Whale Balaenoptera musculus Endangered NMFS No

Plants

American Chaffseed Schwalbea americana Endangered USFWS No

Louisiana Guillwort Isoetes louisianensis Endangered USFWS NoEarth Fruit Geocarpon minimum Threatened USFWS No

a The Florida panther, red wolf, Eskimo curlew, and ivory-billed woodpecker are presumed to be extinct in the State.b There has been no confirmed Bachmans warbler U.S. nesting ground sighting since the mid-1960s, however, several sightings of the

species have occurred on wintering grounds during the last decade. This species may be extirpated in Louisiana.

c For law enforcement purposes, the alligator in Louisiana is classified as "Threatened due to Similarity of Appearance." They are

biologically neither endangered nor threatened. Regulated harvest is permitted under State law.

d Candidate species are not protected under the ESA, but concerns about their status indicate that they may warrant listing in the future.

Federal agencies and the public are encouraged to consider these species during project planning so that future listings may be avoided.

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For a more complete description of all threatened and endangered species occurring

within Louisiana, their critical habitat geographic designations, management

objectives, and current recovery status, refer to the USFWS endangered species

website http://www.fws.gov/endangered/. In addition, the USFWS has published a

report that assigns each species a Listing Status, Lead Region, Population Status,

Recovery Plan, Plan Stage Recovery Achieved, and Recovery Priority (USFWS

1996a).

Figure 4-12. Wintering piping plover critical habitat

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Figure 4-13. Wintering piping plover critical habitat

Coordination with the USFWS and NMFS has been initiated to determine potential

impacts of the proposed action on threatened and endangered species and their

critical habitats. A Biological Assessment (BA) was prepared (see appendix A

Biological Assessment) to address potential impacts to piping plover critical habitat.

Portions of this section concerning organisms under the jurisdiction of the USFWS

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were coordinated and prepared with input from members of the USFWS, Lafayette

Field Office, Endangered Species Section. Portions of this section concerning

organisms under the jurisdiction of NMFS were coordinated with input from

members of the NMFS Endangered Species regional office in Florida.

Threatened and endangered species outside of the Study Area would not likely be

affected by the proposed action. There are no known threatened or endangered

floral species in the vicinity of the proposed action. Piping plovers may winter in or

near the Study Area, frequenting outer beaches and occasionally foraging on

mudflats within the Study Area. Much of the Study Area is designated as critical

habitat for the Piping plover. The West Indian manatee has been reported in the

Barataria-Terrebonne estuary during the summer months and may be a rare visitor

in the Study Area. Threatened and endangered sea turtles typically frequent the

Louisiana coast as they forage in estuarine waters.

Five endangered whale species might be present in offshore Louisiana waters.

During aerial surveys conducted May 1980 - April 1981 in the region south of

Marsh Island, Louisiana, there was only one sighting of endangered whales (Fritts

et al., 1983). The sighting was of a pod of four sperm whales about 229-km (142

miles) south of Marsh Island. Other endangered whale species have been

previously sighted off Louisiana, but they are typically found in water greater than

1,000 m (3,300 ft) deep (Schmidly, 1981; Fritts et al., 1983). The final programmatic

BA for the Louisiana Coastal Area Ecosystem Restoration Study (USACE, 2004b)

indicates a low potential for impacting cetaceans with proposed restoration

measures, which includes the present study, across the entire coastal Louisiana

area. A total of 28 cetaceans have been reported in the Gulf of Mexico waters

(Davis et al., 2002; see also http://www.fws.gov). Of these, five Mysticeti [i.e.,

baleen whales including the blue whale (Balaneoptera musculus), finback whale

(Balaenoptera physalus) and sei (Balaenoptera borealis); and Odontoceiti [i.e.,

toothed whales including the humpback (Megaptera novaeangliae) and sperm whale

(Physeter macrocephalus)] have been reported in the Gulf of Mexico and all are

listed as endangered species. Strandings of whales have occurred throughout the

Gulf coast. However, the infrequent historical sightings and strandings in the

Study Area of these endangered cetaceans suggest that most of these species are

rare, accidental, or uncommon. All whales are principally marine deepwater species

and would not likely be impacted by the proposed action.

There are three species of turtle (Hawksbill, Kemp's Ridley, and Leatherback)

classified as endangered and two species of turtles (Green and Loggerhead)

classified as threatened which may occur in the Study Area. Any of the turtles

could potentially inhabit the general vicinity of the coastal portions of the Study

Area (NMFS and USFWS, 1991a, 1991b; NMFS and USFWS, 1992a; USFWS and

NMFS, 1992b; NMFS and USFWS, 1993). Both green and hawksbill sea turtles are

more tropical in their distribution and rarely seen in the north central Gulf. The

remaining species have been sighted in Louisiana coastal waters. Fritts et al. (1983)

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sighted 15 loggerhead sea turtle individuals and two leatherback sea turtle

individuals. Hard shelled (probably loggerhead) sea turtles were found to be

present in consistent numbers during surveys off Louisiana in April 1987 (0.04

turtles/km2) and October 1987 (0.05 turtles/km2) (Lohoefener et al., 1988).

Leatherback sea turtles, however, showed greater abundance during the October

1987 survey (0.027 turtles/km2 than during the April 1987 survey (0.004

turtles/km2). The reason for the absence of the Kemp's Ridley sea turtle in these

surveys is unknown; however, these turtles are known to be common inhabitants of

the shallow coastal waters between Marsh Island and the Mississippi River Delta.

Coastal Louisiana appears to be an important habitat for sub-adults as well as a

feeding habitat for this species (Hildebrand, 1982).

The Terrebonne Basin barrier island chain falls entirely or partially within two

conservation areas, the State-managed Isle Dernieres Barrier Islands Refuge and

the Barataria-Terrebonne National Estuary Program (BTNEP; a Federal-State

cooperative). Conservation areas, or refuges, have been established in this area to

provide a multitude of management goals. A few fundamental goals that are key to

the protection of threatened and endangered species include: 1) to preserve and

restore wetlands and barrier islands; 2) to realistically support diverse natural

biological communities; and 3) to formulate indicators of estuarine ecosystem health

and balance estuary use (Showalter and Schiavinato, 2004).

Birds

Louisianas coastal wetlands provide habitat for many threatened and endangered

bird species. Though there are five threatened and endangered bird species that

have been identified in the Barataria-Terrebonne system, only the piping plover

uses the barrier islands for nesting and foraging (LDNR, 1998). The brown pelican,

formerly on the threatened and endangered species list was removed from the list in

2009 (Federal Register: November 17, 2009 (Volume 74, Number 220)).

Piping Plover

The piping plover, a relatively small member of the shorebird family, exhibits

strong migratory behavior, but is highly restricted to coastline margins (beaches,

mudflats, etc.). Though the winter distribution of the piping plover spans the

Atlantic and Gulf coasts, the highest concentration of birds have been reported in

Texas, Louisiana, and Florida. However, only 63% of the breeding birds counted in a

1991 survey were identified during the following winter census, suggesting that

important wintering areas are still unknown (USEPA, 2006). On January 10, 1986,

the piping plover was federally listed as endangered in the Great Lakes watershed,

and as threatened elsewhere in its range. In 2001, critical habitat for the wintering

population was designated for 142 areas along the coast of North Carolina, South

Carolina, Georgia, Florida, Alabama, Mississippi, Louisiana, and Texas. The

purpose of this designation was to provide sufficient wintering habitat (and

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appropriate geographic distribution) to support population level recovery of the

piping plover species (USACE, 2004b).

Piping plovers winter in Louisiana, and may be present for 8 to 10 months

annually. They arrive from breeding grounds as early as late July and remain till

late March or April. Piping plovers feed extensively on intertidal beaches, mudflats,

sand flats, algal flats, and was-over passes with no or very sparse emergent

vegetation; they also require unvegetated or sparsely vegetated areas for roosting.

Plovers move among sites as environmental conditions change, and studies have

indicated that they generally remain within a 2-mile area. Major threats to this

species include loss and degradation of habitat due to development, disturbance by

humans and pets, and predation (USFWS, letter dated March 4, 2010).

The primary constituent elements for piping plover critical habitat (wintering) are

found in geologically dynamic coastal areas. Adjacent unvegetated or sparsely

vegetated sand, mud, or algal flats above high tide are also important for roosting

plovers (USACE, 2004b). Piping plover nests are situated above the high tide line

on coastal beaches, sandflats at the ends of sandspits and barrier islands, gently

sloping foredunes, blowout areas behind primary dunes, and washover areas cut

into or between dunes. They may also nest on areas where suitable dredge material

has been deposited. Nest sites are shallow scraped depressions in substrates

ranging from fine grained sand to mixtures of sand and pebbles, shells or cobble

(USFWS, 1996). Nests are usually found in areas with little or no vegetation,

although on occasion, piping plovers will nest under stands of Ammophila

breviligulata (American beachgrass) or other vegetation (USFWS, 1996).

Many of Louisianas barrier islands, and coastal landforms and shorelines have

been designated as critical piping plover habitat (USACE, 2004b). Included in that

designation are the Isles Dernieres and Timbalier Islands reaches. In recent

decades, numerous wintering surveys have been performed to identify active

nesting colonies on the islands. The results of these surveys show active populations

for Raccoon Island (1991: 129 individuals; 2001: 32 individuals), Trinity Island

(1988: 34 individuals; 1991: 29 individuals; 1992: 57 individuals; 1996: 45

individuals), Whiskey Island (2001: 40 individuals), East Island (1996: 29

individuals), Timbalier (2001: 78), and an unnamed sand island between Timbalier

Island and East Timbalier Island (2001: 108) (Ferland and Haig, 2002). Identifying

piping plover habitat, populations, and activity are important since these birds are

known to return to the same wintering sites year after year (USEPA, 2006).

Endangered and Threatened Sea Turtles

The aforementioned species of endangered and threatened sea turtles have

historically visited and foraged along the Louisiana coast and barrier islands

(though the hawksbill is rare in the Gulf; and leatherbacks prefer offshore waters).

Sea turtles are long-lived, slow-reproducing animals that spend nearly all of their

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lives in the water. They require three major habitats: nesting beaches, pelagic

developmental habitats, and benthic feeding habitats for juveniles and adults

(USEPA, 1997a).

Kemps Ridley Sea Turtle

On December 2, 1970 the Lepidochelys kempii (Kemp's ridley) sea turtle was

designated as endangered across its range and its population has continued to

decline in Louisiana (USACE, 2004c). Its nesting areas and habitats include barrier

islands (particularly in south Texas), and nearshore habitats (especially the crabrich waters off the mouth of the Mississippi River) along the Gulf coast. The

sheltered estuaries, bays, and lagoons of Louisiana are primary developmental

areas and feeding grounds for the Kemps ridley (USACE, 2004b).

Occurrence of these sea turtles in bays and estuaries along the Louisiana coast

would not be unexpected, as many of their primary food items occur there. Stomach

analyses of specimens collected in shrimp trawls off Louisiana revealed crabs,

gastropods, and clams Trawlers have also reported seeing this turtle species

frequently in Louisiana waters, The Kemps Ridley accounts for 60% of all

strandings in Louisiana, with 52% of those occurring in the vicinity of the Isles

Dernieres Islands (USEPA, 2005b).

Green Sea Turtle

The Chelonia mydas (green sea turtle) was listed as endangered/threatened on July

28, 1978. The breeding populations off Florida and the Pacific coast of Mexico are

listed as endangered while all others are threatened. This species' current status in

Louisiana is unknown (USACE, 2004b).

Hawksbill Sea Turtle

The Eretmochelys imbricate (hawksbill turtle) was listed as an endangered species

in June 1970 and its current status in Louisiana is unknown. Only one record of a

hawksbill in Louisiana has been reported. Hawksbill turtles nest at low densities in

aggregations of 1 to 100 adults; in contrast, other sea turtles have concentrated

nesting sites and aggregations of thousands of adults. Actions needed to achieve

recovery include long-term protection of foraging habitat and nesting beaches, and

reduction of illegal exploitation (USACE, 2004b).

Leatherback Sea Turtle

The Dermochelys coriacea (leatherback sea turtle) was listed as an endangered

species throughout its range in June 1970 (USACE, 2004b). The leatherback sea

turtle occurs mostly in continental shelf waters, but will occasionally enter shallow

waters and estuaries. Adults are highly migratory, and are believed to be the most

pelagic of all sea turtles. Habitat requirements for juvenile and post-hatchling

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leatherbacks are unknown. In Louisiana, leatherbacks are believed to occur offshore

in deep waters; however, they have been collected from or sighted in Timbalier Bay,

Cameron Parish, Atchafalaya Bay, and Chandeleur Sound (USACE, 2004b).

Habitat destruction, incidental catch in commercial fisheries, and the harvest of

eggs and flesh are the greatest threats to the survival of the leatherback. Recovery

plans are directed at all leatherbacks within U.S. Caribbean, Atlantic, and GOM

waters, whether they are nesting within these areas or elsewhere (USACE, 2004b).

Loggerhead Sea Turtle

The Caretta caretta (loggerhead sea turtle) was listed as a threatened species in

July 1978 and its populations in Louisiana have continued to decline (USACE,

2004b). The largest of the hard-shell sea turtles, the loggerhead is distributed

worldwide in temperate and tropical bays and open oceans. It is probable that the

Loggerhead sea turtle ranges along the entire Louisiana coast; however, previous

reports have documented specimens only from Chandeleur Sound, Barataria Bay,

and Cameron Parish (USACE, 2004b). Although loggerheads have been documented

as nesting on the Chandeleurs in 1962 and Grand Isle in the 1930s, it is doubtful

whether this species currently successfully nests on the Louisiana coast. The

decline in population has been attributed to egg and nestling predation by

mammals and birds. Recent surveys by USFWS Refuge personnel have found no

loggerhead nests in the area (USACE, 2004b).

Fish

The Acipenser oxyrinchus desotoi (Gulf sturgeon) the only threatened fish species

listed in the GOM. On September 30, 1991, the Gulf sturgeon was listed as a

threatened species under the ESA, and the USFWS designated critical habitat for

this species throughout its range on February 28, 2003. The take of Gulf sturgeon is

prohibited in the State waters of Louisiana, Mississippi, Alabama, and Florida.

Section 6(a) of the ESA provides for extended cooperation with states for the

purpose of conserving threatened and endangered species.

The sturgeon is a bottom-dwelling suction feeder (with a ventral, highly extrusible

mouth), which, similar to catfish, detects prey with taste barbels. Subadults and

mature adults participate in upriver migrations in the spring to spawn. During

winter months adults move parallel to shore between estuary systems or offshore

into deeper waters. The Gulf sturgeon inhabits coastal rivers from Louisiana to

Florida during spring and summer, and the estuaries, bays, and marine

environments of the GOM during fall and winter.

Mammals

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The West Indian manatee was listed as endangered throughout its range for both

the Florida and Antillean subspecies in 1967, and received Federal protection with

the passage of the ESA in 1973. Critical habitat was designated in 1976, 1994, 1998,

2002, and 2003 for the Florida subspecies. The West Indian manatee is also

protected under the Marine Mammal Protection Act (MMPA) of 1972. The MMPA

establishes a national policy for the maintenance of health and stability of marine

ecosystems and for obtaining and maintaining optimum sustainable populations of

marine mammals. It includes a moratorium on the taking of marine mammals

(USACE, 2004b).

In the warmer months, manatees disperse from winter aggregation areas, and are

commonly found almost anywhere in Florida where water depths and access

channels are greater than 3.3 to 6.6 ft (USACE, 2004b). In the warmer months,

manatees usually occur alone or in pairs, although interacting groups of 5 to 10

animals are not unusual. A few individuals have been known to stray as far north

as the northern Georgia coast and as far west as the coastal waters of Louisiana

(USACE, 2004b).

Endangered West Indian Manatees occasionally enter Lakes Pontchartrain and

Maurepas, and associated coastal waters and streams during the summer months

(i.e., June through September). Manatees have been regularly reported in the

Amite, Blind, Tchefuncte, and Tickfaw Rivers, and in canals within the adjacent

coastal marshes of Louisiana. The manatee has declined in numbers due to

collisions with boats and barges, entrapment in flood control structures, poaching,

habitat loss, and pollution. Cold weather and outbreaks of red tide may also

adversely affect these animals (USEPA, 2005b).

To avoid any impacts to the West Indian Manatee, the following measures must be

incorporated into all contracts for this Study. All contract personnel associated with

the Study should be informed of the potential presence of manatees and the need to

avoid collisions with manatees, which are protected under the Marine Mammal

Protection Act of 1972 and the Endangered Species Act of 1973. All construction

personnel are responsible for observing water-related activities for the presence of

manatee(s). Temporary signs should be posted prior to and during all

construction/dredging operations or within vessel movement zones (i.e. work area),

and at least one sign should be placed where it is visible to the vessel operator.

Siltation barriers, if used, should be made of material in which manatees could not

become entangled, and should be properly secured and monitored. If a manatee is

sighted within 100 yards of the active work zone, special operating conditions

should be implemented, including: no operation of moving equipment within 50 ft of

the manatee; all vessels should operate at no wake/idle speed within 100 yards of

the work area; and siltation barriers, if used, should be resecured and monitored.

Once the manatee has left the 100-yard buffer zone around the work area on its own

accord, special operating conditions are no longer needed, but careful observations

should resume. Care should be taken to avoid entrapment of individual. Any

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manatee sighting should be immediately reported to the Services Lafayette,

Louisiana Field Office (337/291-3100) and the Louisiana Dept. of Wildlife and

Fisheries, Natural Heritage Program (225/765-2821).

4.2.12 Cultural and Historic Resources

This resource is institutionally important because of: the National Historic

Preservation Act of 1966, as amended; the Native American Graves Protection and

Repatriation Act of 1990; and the Archeological Resources Protection Act of 1979; as

well as other statutes. Cultural resources are technically important because of:

their association or linkage to past events, to historically important persons, and to

design and/or construction values; and for their ability to yield important

information about prehistory and history. Cultural resources are publicly

important because preservation groups and private individuals support their

protection, restoration, enhancement, or recovery.

4.2.12.1 Historic Conditions

Humans have made a progressive mark on coastal Louisiana for thousands of years.

Archaeological remains found in Louisiana indicate that man has occupied the area

since around 10,000 B.C., primarily as nomadic hunter-gatherers that migrated

with the fluctuations of the Mississippi River. The diverse resources available in

coastal Louisiana have led to a diverse history and rich culture in the Louisiana

coastal area. As a result, cultural resources are abundant in the region. Over the

last 50 years, as land loss has progressed and saltwater intrusion has increased,

many of these cultural resources have been put at risk or lost to erosion,

inundation, and construction of canals (USACE, 2004a). The SHPO is charged with

the responsibility of maintaining the central files of all the archaeological and

historical standing structures data. All cultural resources survey reports and forms

conducted under the National Historic Preservation Act (NHPA) are archived in

their offices in Baton Rouge (USACE, 2004b).

Prehistoric sites include hunting and food processing camps, hamlets, and village

sites. Native Americans relied on hunting, fishing, and gathering of plants. Types

of historic sites include domestic buildings, plantation sites, farmsteads, military

sites, commercial sites, industrial sites, boat landings, and hunting and fishing

camps along the coast. In addition to terrestrial historic sites, the Study Area has

the potential to contain historic shipwrecks. Watercraft from all time periods could

be present in the Study Area. Most of the vessels used historically in this area were

vernacular watercrafts (USACE, 2004b).

In the early 1900s, various subsistence activities that were initially developed prior

to the 20th century became more commercial in nature. Seafood, one of the most

important natural resources in south Louisiana, has continued to become more

important to the economy of Louisiana. In the middle of the 19th century, methods

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of preservation such as the drying of shrimp and canning of oysters made it possible

to export seafood. The introduction of the gasoline motor and refrigeration allowed

fishermen greater access to markets in New Orleans and the larger towns inland

from the coast. Seafood processing camps that had been established all over the

coast in the 1800s, including Manila Village, Bayou St. Malo, and the Isle de

Caminada, were abandoned after being hit by numerous tropical storms and

hurricanes. In the 1900s, many of these fishermen established new settlement and

seafood processing businesses along the major waterways leading away from the

coast. Fishing remains a major economic activity in south Louisiana (USACE,

2004b).

Other industries developed in south Louisiana in the 1900s that have shaped the

economy of the State. The oil industry began in the early 1900s and continues to be

a major industry. Large oil fields are located in the marshy areas of south

Louisiana and offshore. Pockets of sulfur and salt are located across south

Louisiana. The extraction of these natural resources became major industrial

activities. All of these economic activities have contributed to the constructed

environment of south Louisiana. Historic standing structures, archaeological sites,

and landscape features associated with mans activities in the coastal area may be

significant cultural resources. The Division of Archaeology maintains information

on over 12,000 archaeological sites and thousands of historic standing structures

(USACE, 2004b).

4.2.12.2 Existing Conditions

The land in the Study area is eroding rapidly. The protection of these lands by

some of the ongoing CWPPRA or other restoration projects may actually protect

these sites in the long-term by stopping or slowing land erosion. Depending on the

restoration features, the proposed actions could help to restore the surrounding

wetlands, thus protecting the land and whatever cultural resources that may be

located within the Study area.

Barrier Islands

A cultural resource assessment of six areas of potential effects (APEs) within the

Study area was performed by R. Christopher Goodwin and Associates, Inc. in

December 2009 (Nowak et al. 2010). The APEs investigated included the footprint

of the design plans for each of the individual islands composing the Isles Dernieres

and Timbalier barrier island reaches. The cultural resource assessment reviewed

the geomorphology, prehistory, history and archaeology of the Isles Dernieres and

Timbalier Islands to ascertain the probability for the presence of significant cultural

resources, i.e., those archaeological sites and historic properties possessing the

qualities of significance and integrity defined by the National Register of Historic

Places Criteria for Evaluation (36 CFR 60.4[a-d]).

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Research included the review of archeological site files within 10 miles of the of the

barrier island APEs, the results of previous investigations conducted within one

mile of the barrier island APEs, and databases (including the National Oceanic and

Atmospheric Administration Automated Wreck and Obstruction Information

System (AWOIS), the Minerals Management Service shipwreck database, and the

Louisiana shipwreck database) reporting the locations of shipwrecks and

obstructions within 10 miles of the barrier island APEs. The geomorphology of Isles

Dernieres and the Timbalier Islands was also reviewed as it relates to the potential

for the existence of significant cultural resources. Historic maps and charts dating

from 1853 to the present were reviewed along with the results of previously

conducted geomorphologic studies that endeavored to reconstruct the historic

shorelines of these island chains. Finally, historical research was conducted in order

to ascertain the nature and extent of historic navigation within the general vicinity

of the Study Area.

The review and correlation of the geomorphology of the Study Area with the

regional prehistory and archaeological record of this part of south Louisiana

indicate a low probability for significant prehistoric archaeological sites or

prehistoric watercraft within the barrier island APEs. Additionally, any prehistoric

archaeological remains that exist within these areas likely will consist of reworked

and/or redeposited accumulations of cultural materials lacking integrity and having

little research value (36 CFR 60.4[d]).

Consideration of the geomorphology and history of the Study Area also suggests

that there is a low probability for significant historic archaeological sites or

standing structures since no historic occupations were noted on terre firme within

the Study Area. However, various probabilities for the discovery of historic

shipwrecks exist within the barrier island APEs, as summarized below.

Raccoon Island

Within the Raccoon Island APE, a high probability for historic shipwrecks is

indicated near Raccoon Point, while a moderate probability for such resources is

present to the east of this area. Ships could have grounded on shoals within these

areas as they attempted to navigate the natural channels behind the island. A low

probability for historic shipwrecks is indicated along the entire Gulf Coast of the

island, since waters south of the shoreline within the APE were subaerially exposed

until the mid-twentieth century.

Whiskey Island

The potential for historic shipwrecks within the Whiskey Island APE generally is

similar to Raccoon Island. Although no reported historic shipwrecks are recorded

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within this area, and while ships traveling to and from the village on Isle Dernieres

probably did not pass within the Whiskey Island APE, Confederate blockade

runners probably did pass behind this reach of Isle Dernieres. As a result, the

northwestern portion of the Whiskey Island APE has a moderate probability for

historic shipwrecks. Areas within the APE south and west of this region were

subaerially exposed until the mid-twentieth century; thus, they should be

considered to have low potential for historic shipwrecks.

A Phase I submerged cultural resources remote sensing investigation was

conducted by R. Christopher Goodwin and Associates, Inc. within the vicinity of

Whiskey Island (Nowak et al. 2010b). Thirteen (13) targets exhibiting the potential

to represent submerged cultural resources were identified, although none of the

magnetic anomalies that compose those targets could be associated with side scan

sonar contacts, suggesting that all thirteen (13) targets are buried.

Trinity and East Islands

The Trinity and East Island APE was largely subaerially exposed until the midtwentieth century. Coastal Environments, Inc. (Kelley et al. 2009) recently studied

a portion of the East Island APE, and no significant cultural resources were

identified during that study. The Trinity and East Island APE is considered to have

low probability for historic shipwrecks.

Wine Island

Modern Wine Island is a relatively recent landform. The area it occupies was open

water prior to and during the nineteenth and early twentieth centuries. Ships

entering or exiting Lake Pelto would have passed close to this area. One reported

shipwreck, the schooner Lizzie Haas foundered in a gale near Wine Island during

1902. Considering the position of modern Wine Island near the eastern entrance to

Lake Pelto, there is a moderate probability for historic shipwrecks within the Wine

Island APE.

Timbalier Island

Three ships are reported to have been lost in the immediate vicinity of Timbalier

Island. These include the sidewheel steamer Merchant, the schooner Thistle, and

the bark Gerhardus (Birchett and Pearson 1998:21-24; Clune and Wheeler 1991;

New York Times Jan. 22 1897). These ships were lost during 1842, 1877, and 1897,

respectively. A portion of the Timbalier Island APE also was investigated recently

by Coastal Environments, Inc. (Kelley et al. 2009). No significant cultural resources

were identified during that study. As a result, only the areas immediately adjacent

to but outside of the footprint of the aforementioned Coastal Environments, Inc.

investigation can be considered to have a moderate potential for historic

shipwrecks.

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East Timbalier Island

East Timbalier Island is a relatively recent landform. The area it occupies was open

water prior to and during the nineteenth and early twentieth centuries. No

shipwrecks have been reported within the East Timbalier Island APE. However,

ships sailed through the area now occupied by this island throughout the historic

period and could have foundered within the APE. Normally, there would be a

moderate probability for historic shipwrecks within such an area. However, review

of oil and gas field data from the Louisiana Department of Natural Resources

SONRIS system indicates that extensive disturbance has occurred within the East

Timbalier Island APE. As a result, a low-to moderate probability exists for historic

shipwrecks within the East Timbalier Island APE.

In addition, Trinity Island hosts the Whiskey Pass Silver King Association statue of

the Madonna, which was originally placed on Whiskey Island by the Association in

the 1960s, but was eventually moved to Trinity Island in the 1970s. Members of the

Association have been responsible for occasionally moving the statue in order to

protect it from degrading island conditions. R. Christopher Goodwin and

Associates, Inc. investigated the Whiskey Pass Silver King Association statue of the

Madonna on Trinity Island (Figure 2-19) and determined that the statue does not

possess significance of associations with important historic patterns or events, for

associations with important personages, for its qualities of design or construction, or

for its potential to yield important information, as required under the National

Register Criteria for Evaluation (36 CFR 60 [a-d]). The statue will be avoided or

temporarily relocated during a restoration event.

Section 106 consultation was initiated with the Advisory Council on Historic

Preservation (ACHP), SHPO, and federally recognized Indian tribes in May 2009.

The results of the cultural resource assessment of the barrier island APEs revealed

no known listed National Register of Historic Places properties or sites eligible for

listing on the National Register of Historic Places, and the results of the cultural

resource assessment were coordinated with the SHPO. In a letter dated March 22,

2010, the SHPO concurred with the general findings concerning the probabilities of

prehistoric and historic cultural resources and shipwrecks within the APEs. The

results of the Phase I remote submerged cultural resources remote sensing

investigation in the vicinity of Whiskey Island have not yet been coordinated with

SHPO or Indian tribes. However, in consultation with the ACHP, SHPO, Indian

tribes, representatives of local governments, and other consulting parties, the

USACE developed a Programmatic Agreement among the USACE, CPRA, SHPO,

and ACHP, pursuant to 36 CFR § 800.14(b)(1), executed July 29, 2010. The

Programmatic Agreement establishes the procedures for consultation, identification

of historic properties, assessment and resolution of adverse effects, and is included

in Appendix F. The execution and implementation of the Programmatic Agreement

fulfills USACE obligations under Section 106 of the National Historic Preservation

Act of 1966, as amended.

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Borrow Areas

Five sediment sources have been identified for use as borrow for either beach and

dune restoration or marsh creation and restoration. The five source locations have

been investigated to determine if any historic properties exist within the area of

potential effects (APE), and the results are summarized below. The locations of

potential sites, possibly representing either historic shipwrecks or prehistoric sites,

will be avoided, and the USACE will continue consultation with the SHPO and

federally recognized Indian tribes, pursuant to the stipulations of the Programmatic

Agreement.

Whiskey Island Restoration Borrow Area 3

Whiskey Island Restoration Borrow Area 3 is located approximately three miles

south of Trinity Island in State waters. Water depths vary between -16 ft and -22 ft

NAVD 88. Subsurface sand resource thickness ranges from 2.5 to 14.0 ft and is

overlain by varying thicknesses of overburden ranging from 3.5 ft to 17.4 ft.

As part of a separate coastal restoration effort (TE-50), two integrated

hydrographic/geophysical surveys were conducted within the Whiskey Island

Restoration borrow area in 2006 (TBS and M&N 2007). The resultant surveys

included the acquisition and analysis of more than 260 statute miles of multi-sensor

marine geophysical data (sounding, seismic/sub bottom Chirp profiling, and

magnetic) in a LDNR-approved search area. Remote-sensing cultural resource

investigations of Subarea 3a revealed several areas where magnetic anomalies were

detected. Of the 247 magnetic anomalies identified, only twenty-four were

considered to be potentially significant cultural resources and recommended for

avoidance by Archaeological Resources, Inc. (TBS and M&N 2007). The borrow

area limits and avoidance area are included in Appendix L.

New Cut Borrow Area 4

The New Cut Borrow Area 4 is an existing active borrow area in State waters

previously utilized by LDNR. Seismic and magnetometer surveys have been

conducted throughout this borrow area. Avoidance area locations were developed

based on these surveys and included on as-built drawings for the New Cut

Dune/Marsh Restoration (TE-37) project. One avoidance area is located within the

TE-37 excavation limit (Appendix L). The nature of this avoidance area could not

be determined from the existing information. The borrow area limits and avoidance

area is included in Appendix L.

Raccoon Island Restoration Borrow Area 5

The Raccoon Island Restoration Borrow Area 5 is located approximately four to six

miles south of Raccoon Island in Federal waters. The bottom depth at the north end

of the borrow area is -23.5 ft (NAVD 1988), sloping downward to -26.5 ft (NAVD

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1988) at the lower end (SJB et al., 2006). A remote-sensing cultural resources

investigation, which included approximately 100 nautical miles of remote sensing

side-scan and magnetometer surveys was conducted at this location in 2008

(Goodwin 2008). Based on this investigation the borrow area was refined to

approximately 600 ft in width and 10 to 20 ft in depth.

Review of the geology, prehistory, and history of the investigated area indicate that

there is low potential for the discovery of both submerged prehistoric cultural

resources and for the discovery of submerged historic cultural resources, such as

shipwrecks. The magnetometer data indicated one pipeline, one anomaly cluster

that may represent a pipeline, and three anomaly clusters that may represent

significant submerged cultural resources. No potentially significant side-scan sonar

contacts were identified. The report recommended avoidance of the

abovementioned anomalies. The borrow area limits and avoidance areas are

included in Appendix L.

South Pelto Borrow Area 6

South Pelto Borrow Area 6, which includes MMS South Pelto Lease Blocks 12 and

13, is located in Federal waters of the Gulf of Mexico approximately 9.5 miles south

of Isle Dernieres. Water depths in the borrow area range from 26 to 48 ft. A remotesensing cultural resources investigation, which included side-scan and

magnetometer surveys was conducted in 2003 (C & C 2003b). The survey was

conducted according to MMS guidelines at that time, which required 50-meter grid

spacing. Numerous sonar targets and magnetometer anomalies were recorded.

Based on these findings, ten avoidance areas were proposed within the borrow area.

The borrow area limits and avoidance areas are included in Appendix L.

Ship Shoal Borrow Area 7

Ship Shoal Borrow Area 7, which includes MMS Lease Blocks 87, 88, 89, 94, and 95,

is located in Federal waters of the Gulf of Mexico approximately 10 miles south of

Whiskey Island. The hydrographic conditions across most of the borrow site are

relatively flat, with the controlling depths ranging from -17 to -23 ft NAVD 88. All

of these lease blocks are identified by the MMS as high probability areas relative to

prehistoric archaeological site potential and Blocks 88, 89, and 94 are identified as

high probability blocks relative to historic shipwreck potential. Ship Shoal deposits

have the potential for containing cultural remains dating to the Middle Archaic

period (circa 7,000 to 5,000 years B.P) (C & C 2003a). Evidence suggests that Ship

Shoal deposits have been churned, reworked, and extensively burrowed over the

past several thousand years such that any cultural remains contained in them have

been disturbed and will not be in situ (Penland et al. 1985).

Substantial geophysical surveys which included side-scan sonar and magnetometer

surveys were conducted along lines spaced at 50-meter intervals across the borrow

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area as part of a separate coastal restoration effort (C & C 2003a). Based on these

surveys, two areas were recommended for avoidance because of potentially

significant cultural resources. The borrow area limits and avoidance areas are

included in Appendix L.

4.2.13 Aesthetics

4.2.13.1 Historic Conditions

This resources institutional significance is derived from laws and policies that

affect visual resources, most notably the National Environmental Policy Act of 1969,

the Coastal Barrier Resources Act of 1990. This resource is technically significant

because of the visual accessibility to unique geological and botanical features that

are an asset to the Study Area. Public significance is based on expressed public

perceptions and professional evaluation.

It is National policy that aesthetic resources be protected along with other natural

resources. Current planning guidance specifies that the Federal objective of water

and related resources planning is to contribute to National Economic Development

consistent with protecting the Nation's environment (ER 1105-2-100). The Corps

established a number of environmental goals, including: (1) Preservation of unique

and important aesthetic values; and, (2) Restoration and maintenance of the

natural and man-made environment in terms of variety, beauty, and other

measures of quality (ER 200-2-2). The Visual Resources Assessment Procedure

(VRAP), WES Instructional Report EL-88-1, will be used to:

1. Identify and assess the existing visual resources conditions affected by the

study.

2. Assess (describe magnitude, location, duration) and appraise (determine if

beneficial or adverse) the visual impacts caused by alternatives.

3. Provide a replicable basis of support for any recommended mitigation.

The purpose of using this procedure is to have a systematic approach to consider

aesthetic resources. Advantages of a systematic and quantifiable approach include

the ability to assign a visual resource value to all of the landscape units within a

Study Area, identify significant aesthetic resources, and to determine causes of

adverse impact. Such a procedure provides a clear, tractable basis for including

aesthetics in plan formulation, design, reformulation, and mitigation planning. As

such, the VRAP is consistent with existing Federal and Corps water resources

planning and environmental policies and regulations.

Data sources describing the historical aesthetic condition of the Study area are

limited. Sothern (1980) described Last Island (the chain of islands making up Isles

Dernieres) as a popular resort visited by well-known, prominent people from

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throughout the State. Sothern (1980) provides general descriptions of the island

obtained from newspaper articles from the mid-1800s promoting Last Island as a

vacation destination and an escape from the yellow fever epidemic of 1853.

Historical accounts and a United States Coastal Survey Map of 1853 indicate that

most of the dwellings as well as a hotel were situated near the western end the

island facing the Gulf. The following account published in the Planters Banner in

1848 was included by Sothern (1980) and provides and vivid account of the historic

aesthetics enjoyed by vacationers on Isles Dernieres in the 1800s:

The beach is smooth, and covered with small white shells, the water is clear and

salt, and not over five ft deep, for a distance of two hundred yards form the shore,

and when the tide is coming in, the waves roll upon the beach one after another in so

beautiful succession, that any one who looks upon them must be highly gratified at

the sight. This beach is certainly one of the finest places for promenading I have ever

seen. Its surface is smooth and firm, it is always cool on account of its being

contiguous to the salt water which so uniformly washes its surface, a gentle sea

breeze is always floating across it, and health and vigor seemed to be inhaled at

every breath by those who visit it (Sothern 1980).

4.2.13.2 Existing Conditions

Visually the Terrebonne Basin barrier islands owe their diversity to variations in

flora and fauna, and the interface of the GOM and marsh. The surf and songs of

numerous birds offer a variety of sounds. For many visitors, the smell and feel of

salty air, and the variety of nature, add to the appeal of the islands (USEPA, 1993).

Today the remains of fishing camps and petroleum-related infrastructure dominate

the barrier islands' human-made landscape.

The Isles Dernieres and Timbalier Barrier Islands are low-lying strips of land

ranging from approximately 0.1 to 0.85 miles wide and are typically composed of a

thin sand cap over a thick mud platform. Elevations are generally low and the

islands are frequently overwashed (USACE, 2004c). From a typical view from the

bayside of the islands facing gulfward, one would encounter shallow unvegetated

subtidal flats gradually transitioning into a smooth cordgrass and mangrovedominated salt marsh. Just beyond the marsh and mangrove flats, one will

encounter a sparsely-vegetated saltpan then a grassy swale and shrub-dominated

barrier flats. Low-lying dunes are covered with marshhay cordgrass, goldenrod,

and coastal dropseed. The low-lying dunes would be frequently bisected by

overwash fans from recent storms. Moving gulfward, one would encounter a

sparsely-vegetated beach littered with driftwood and miscellaneous artifacts from

the commercial fishing and petroleum extraction industries. From almost any view

gulfward, one would observe commercial fishing boats and oil and gas platforms in

the nearby gulf waters.

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4.2.14 Recreation

4.2.14.1 Historic Conditions

Early accounts of recreational activities on Isles Dernieres were provided in Sothern

(1980). In leading up to the tragic hurricane of 1856, Sothern documents the

transition of Last Island from a fishing village to a resort frequented by wealthy

plantation owners during the summer months. The yellow fever epidemic in 1853

made the barrier islands more attractive because common belief at the time was

that the disease was rarely contracted in saltwater environments. Caillou Island

and Timbalier Island appeared to have been favorite destinations for residents from

Terrebonne Parish, while the planters along Bayou Teche and upper Bayou

Lafourche preferred Last Island. Bathing, fishing, hunting, and exploring were

common recreational activities reported during the 1800s.

4.2.14.2 Existing Conditions

Louisiana possesses approximately eight million acres of coastal lands, marshes,

lakes, swamps and bays, and approximately 13 million acres of forests. These

resources and the recreation activities in which they support (sport fishing, hunting,

boating, water skiing, swimming, hiking, and camping) have grown considerably in

recent years. Not only have the number of recreationally linked visits to these

facilities and natural areas increased, but over the last decade so have the diversity

of non-traditional settings and activities. According to the USFWS National Survey

of Fishing, Hunting, and Wildlife-Associated Recreation (Louisiana Department of

Culture, Recreation, and Tourism, 2006) and the Louisiana Department of Wildlife

and Fisheries study on The Economic Benefits of Fisheries, Wildlife and Boating

Resources in the State of Louisiana  2006 (2008d):

 1.2 million Louisianans, ages 16 and over, participated in wildlife-associated

recreation. This figure represented 28%of the population. The national

percentage is 20.

 Of the 1.2 million Louisiana sports persons ages 16 and older, 702,000 fished,

270,000 hunted, and 738,000 enjoyed both fishing and hunting. Louisianas

proportion of the sports in these categories was slightly higher than the

national average.

 In 2006, state residents and non-residents 16 years and older who fished in

Louisiana numbered 702,000. Of this total, 590,000 anglers (84%) were state

residents and 112,000 anglers (16%) were non-residents. Resident and

nonresident anglers fished a total of 11.2 million days in Louisiana  an

average of 16 days per angler.

 Eighty-six percent of the States 549,000 freshwater anglers were state

residents.

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 Eighty-six percent of the 289,000 saltwater anglers were state residents.

 706,000 state participated in wildlife watching activities in Louisiana.

 193,000 people (27% of all wildlife watchers in Louisiana) participated in

wildlife watching activities at least 1 mile from their home. Of these, 203,000

were state residents and 111,000 were non-residents.

The majority of these recreational activities and facilities are located in the

Louisiana coastal zone. These activities are often linked to localized heritage,

tradition, prominent commerce, or other historical events. Examples of these are

the hundreds of cuisine, wildlife, industry, and culturally-based festivals that are

celebrated throughout the coastal zone.

Much of the recreation data has been extracted from the 2009  2013 Louisiana

Statewide Comprehensive Outdoor Recreation Plan (SCORP), which is updated at

five-year intervals (SCORP, 2003). The SCORP not only inventories statewide

recreation resources, but also identifies and prioritizes the areas of need.

Additional information on outdoor recreational activity in Region 3 can be found in

Appendix E of the 2003 SCORP Report.

The Study Area is located within Region 3, which includes Terrebonne and

Lafourche Parishes along with Assumption, St. James, St. Johns and St. Charles

Parishes. Detailed data on outdoor recreational activity in Region 3 is contained in

Appendix E of the 2003 SCORP Report.

Additional data were obtained from the Louisiana Department of Wildlife and

Fisheries web site (http://www.wlf.louisiana.gov/education/economics/). According

to The Economic Benefits of Fisheries, Wildlife and Boating Resources report

(Southwick Associates 2006), The fish, wildlife and boating resources of Louisiana

generate substantial benefits. Hundreds of thousands of people depend on these

resources for recreation, employment and as a source of food for their families.

These valuable resources, actively managed by the Louisiana Department of

Wildlife and Fisheries, not only contribute to the standard of living and economic

health of state residents, but also to the common good through state tax revenues.

The total impact of these activities amounted to:

 $4.61 billion of Retail Sales

 $6.75 billion of total Economic effect

 $446.2 million State and Local Tax Revenues

 76,700 jobs supported

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Sportspersons and wildlife watchers spend $110 billion annually, 1.1% of the

Nations gross domestic product. Preliminary findings in the State of Louisiana,

from the USFWS 2001 FHWAR, show that 970,000 sportspersons participated in

fishing with expenditures of $694,978 and 333,000 participated in hunting with

expenditure of $416,953. Wildlife-watching participants numbered 802,000 resident

and 314,000 nonresident with expenditures of $165,746. In this region of the

country, 19% of the population are anglers, 9% are hunters, and 25% participate in

wildlife-watching activities.

Americans traveling to Louisiana spent approximately $9 billion in 2007. This

supported over 178,000 jobs in the State with annual income of about $2.8 billion.

Tax revenues associated with recreation and tourism in Louisiana were about $5.9

billion for all levels of government. Thus, tourism is an important resource in the

State of Louisiana (www.crt.state.la.us).

The Louisiana SCORP included some general needs and needs for specific regions.

Some of the general needs included the need for more quality accommodations and

camping facilities with more activities; the need to improve access to lakes for the

average public; the need to enlarge timber-vegetated buffer strips of timber along

streams, roads, and lakes to preserve plant communities and enhance water quality

by filtering stormwater runoff, the need for more and improved local recreational

opportunities; the need for more intense trail systems; the need for more regional

promotion and packaging of outdoor recreation; the need for urban wilderness

parks; and the need for public education on conservation and facility use. Table 4-

11 displays Federal, State, and other important recreational resources.

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Table 4-11 Federal, State, and other areas of important recreational

resources

Wildlife/Recreation Areas State Total Terrebonne

Basin

USFWS National Wildlife Refuges 16 1

National Historic Parks and Preserves 6 0

Louisiana Wildlife Management Areas

and Refuges 36 2

Louisiana State Parks 17 0

State Historic Sites 12 0

Important Bird Areas 15 2

Scenic Byways 16 1

Annualized Unit Day Value (UDV)* $4.05 billion $66.1 million

The Louisiana SCORP inventoried over 104,000 acres (42,120 ha) of recreational

facilities (these are public facilities and acres, and do not account for private lands

and leases) for SCORP Region 3 (roughly Terrebonne Basin). Region 3 includes

Terrebonne, Assumption, St. James, St. John, St. Charles, and Lafourche Parishes.

Public lands in the Terrebonne Basin includes one USFWS National Wildlife

Refuge, the Mandalay National Wildlife Refuge; one wildlife management area

(WMA), the Pointe-Au-Chein WMA, and one Scenic Byway, the LafourcheTerrebonne Scenic Byway (Wetlands Cultural Trail) that has routes through

portions of southern Terrebonne Parish. The Terrebonne Barrier Island Refuge

includes portions of Raccoon, Whiskey, and Trinity Islands.

With the inclusion of private lands, more than 107,000 acres (43,335 ha) are

available for hunting. The region also has 194 boat lanes at 105 boat ramps; 131

acres (53.1 ha) with 365 tables for picnicking; 1 beach of 37 acres (14.9 ha); and 71

acres (28.7 ha) for camping with 34 tent sites and 422 trailer-sites. These resources

alone are conservatively estimated to have an annualized UDV of over $286 million.

The SCORP prioritized needs in this region/subprovince, which include the need to

maintain cultural heritage while increasing benefits associated with outdoor

recreation and tourism, the need to promote and improve upon what is there (e.g.,

fishing, marsh, foods, etc.), the need for more public access to marshes, the need to

protect the barrier islands, and the need to provide aid to recreation-related

businesses.

The extensive marsh wetlands, water bodies, beaches and barrier islands of

Louisianas coastal area are ideally suited for outdoor recreational activities. The

biological wealth and productivity of these natural resources support many species

of native plants and animals, and also provide for a variety of recreational pursuits.

Major recreational activities occurring in the coastal area, specifically in and around

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barrier islands include sport fin-fishing (the most popular); waterfowl, recreational

shrimping; boating; swimming; sailing; picnicking; camping; hunting; bird

watching; and observing wildlife.

There are limiting factors on the potential recreational use of these abundant

resources. These limiting factors include private land ownership, lack of public

access, and competition with commercial activities such as commercial fishing and

shrimping, and mineral exploration and extraction. The ever-increasing loss and

shifting of the barrier islands resource itself is also a factor, limiting potential

recreational use. Many of the camps located on the barrier islands are privately

owned and are not available to the general public. Public access to the barrier

islands are provided by public boat launching facilities found throughout the Study

Area. Generally, these facilities are located along the developed ridges of land that

extend along the Mississippi River or its former meanders into the marshlands.

Approximately 30 boat-launching facilities provide recreational boat access to the

Study Areas barrier islands.

Saltwater finfish species, such as spotted sea trout and redfish, are taken

recreationally. Crabs, shrimp, and flounder are also a significant part of the

recreational fishery. Waterfowl hunting is predominant in the wetlands protected

by the barrier islands. This is because the marshes lie within the Mississippi

Flyway, which is used extensively by many migratory birds.

The barrier islands of the Terrebonne Basin are also a resting area for migratory

neo-tropical songbirds and waterfowl. Many of these birds are passing through

coastal Louisiana on their way to nesting areas northward.

Many local and out-of-state sportsmen use numerous marsh camps that serve on a

seasonal or weekend basis of operation as a starting point for various outdoor

activities. Many of these camps, which are only accessible by boat, serve as

clubhouses for the coastal areas numerous fishing and hunting clubs. Others are

privately owned and are used almost exclusively for family oriented recreation.

Numerous camps are located in the Study Area.

Hunting and fishing are the primary recreational activities along the Terrebonne

Basin barrier island chain. The use of watercraft is required for access to, and

recreational use, of the barrier islands and associated marshes. The recreational

use of the islands provides business for private boat launches, sport-fishing

charters, and local supply companies (USFWS, 2003). Recreation in the Study area

has benefited from the Louisiana Statewide Comprehensive Outdoor Recreation

Plan. This plan has worked to prioritize recreational needs and requirements, and

to promote interaction and cooperation between the local, State, Federal, and

private recreation programs (USACE, 2004b). Also benefiting from these

recreational plans are the commercially and recreationally important fishes and

shellfishes (i.e. red drum, blue crab, white shrimp and the American oyster), which

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frequent the barrier islands and wetlands located within the Study area (USFWS,

2003).

Continued barrier island and wetland loss would significantly affect recreational

resources and activities in coastal Louisiana (USFWS, 2003). Reductions in these

activities would have devastating effects since recreational activities have been

shown to improve the quality of life, and are key components of the States tourism

and economic development plans.

4.2.15 Socioeconomics and Human Resources

This resource is institutionally significant because of the National Environmental

Policy Act of 1969; the Estuary Protection Act; the Clean Water Act; Section 122 of

the River and Harbors Acts; the Watershed Protection and Flood Protection Act;

and the Water Resources Development Acts. Of particular relevance is the degree

to which the proposed action affects public health, safety, and economic well being;

and the quality of the human environment. This resource is technically significant

because the social and economic welfare of the nation may be positively or adversely

impacted by the proposed action. This resource is publicly significant because of the

public's concern for health, welfare, and economic and social well being from water

resources projects.

To place this resource in perspective, one should understand that the barrier

islands of the Atlantic and Gulf of Mexico coasts present a complex picture of

human adaptability in the face of environmental, social, and economic factors:

factors that can be complementary or competitive and often under the control of the

weather and other natural phenomena beyond the influence of man. Depending

upon geography, man has fished, trapped, hunted, and/or farmed barrier islands, as

well as salvaged shipwrecks and their flotsam and jetsam, for centuries. Other, less

savory occupations, such as smuggling, moonshine distilling, and piracy have also

been prevalent, because of the frequent geographic complexity and extreme

difficulty of access without local knowledge. Jean Lafitte, Jose Gaspar, Black

Caesar, Captain (Thomas) Kidd, and the wreckers of the Florida Keys and Key

West, come to mind. The pre-Columbian Calusa Indians of the Southwest Florida

coast created a thriving culture within the coastal barrier system. Their

settlements were sited on numerous elevated mounds composed almost entirely of

oyster, clam, and gastropod shells, evidence of the productivity of the wetland

system on which they depended. In a similar manner, the Paleo-Indians of the

Louisiana coast, residing on the natural levees and chenieres but dependent on the

natural resources of the adjacent marshes, left mounds or middens containing the

shells of the same or similar mollusks, plus fish, bird, and mammal bones, ash, and

other domestic debris (Davis, 2010).

In the northern Gulf of Mexico, the marshes that exist on the bay sides of the

barrier islands and their adjacent uplands are nursery areas for a broad range of

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commercially and recreationally important species of invertebrates and finfish and

other profitable organisms, such as the fur-bearing Muskrat. Similarly, the open

water areas, bays, tidal channels, and bayous, provide foraging areas and shelter

for juveniles and adults of the same and other commercially and recreationally

important species, including the American Alligator. As the barrier islands and

associated marshes diminish and disappear, the ecosystem for which they provide

the habitat diminishes, and the opportunities for the people whose livelihoods

depend on that ecosystem also diminish. This diminution also jeopardizes the

infrastructure that has been erected to serve another resource use, the petroleum

extraction and processing sector. The barrier islands protect many oil and gas wells

and their associated transmission, storage, and processing facilities, in, on, and

behind the islands. Absent the islands, these wells, pipelines, and facilities would

be exposed to the open sea, and the cost of reducing their vulnerability would be

considerable. Another aspect of the environment that is jeopardized by the loss of

the barrier islands is the estuarine nature of the marshes and bays they protect.

The islands provide a physical barrier to salt water intrusion. As the islands reduce

in size and the passes between them increase in width, the brackish water interface

moves farther up into the bays, resulting in loss of freshwater marsh and swamp

forest to open water. Such changes impact those who are dependent on the

environment for their livelihood by eliminating or altering the habitat of the

organisms they target. Oysters that require an estuarine salinity range for growth

and survival do not thrive in an environment that is too fresh or too salty. In a like

manner, juvenile fish that both shelter and feed in a vegetated marsh environment

will not thrive, or even survive, on a mudflat or in open water.

Because the natural resources of the Louisiana barrier islands and associated

wetlands provide such a wide array of products, and their distribution away from

the coast involves so many different kinds of commerce, the repercussions of

diminishing resources are felt at a national level.

At the present rate of land loss, the disappearance of the five Isles Dernieres has

been predicted to occur by TY40 (2052), with the Timbaliers lasting barely beyond

TY50 (2062), at which date Timbalier Island is predicted to be only 2 acres of

intertidal habitat and East Timbalier only 4 intertidal acres (Table 3-19). The

repercussions of the loss will go way beyond disturbance of the above-referenced

natural resources and resource-based commercial and recreational activities. The

islands, marshes, and wetland forests provide storm protection for the uplands. All

of the communities, industrial areas, and transportation infrastructure to the north

of the Terrebonne-Barataria Barrier Islands will be placed at risk.

As referenced above, mans activities in the Louisiana barrier island ecosystem have

been ongoing since prehistoric times. The social fabric and cultures of the diverse

groups of people who inhabit the Louisiana coastal area is so interconnected with

the environment that its continuing disturbance and disruption has led to an

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undercurrent of anxiety within the permanent population, whose extended families

have lived in this coastal area for many generations (Gramling and Hagelman,

2005: 132; Laska, et al., 2005).

4.2.15.1 Population and Housing

4.2.15.1.1 Historic Conditions

Detailed historical information for population and housing was not available for the

Study Area. Based on review of available literature (e.g., Williams et al. 1992), in

the middle of 1800s, Last Island (Isles Dernieres) was a popular vacation resort and

had numerous summer cottages and a large hotel. In August 1856, a hurricane

completely destroyed the village. The Village of Last Island was never rebuilt.

Isles Dernieres and the Timbalier Islands have, for the most part, remained

uninhabited by permanent residents since that time.

4.2.15.1.2 Existing Conditions

The Study Area is located in remote and uninhabited coastal wetlands within

Terrebonne, and Lafourche Parishes. There are no permanent communities or

human populations in the Study Area. The nearest populated areas to the Isle

Dernieres and Timbalier Islands are Cocodrie, Port Fourchon and Grand Isle,

Louisiana.

4.2.15.2 Employment and Income

4.2.15.2.1 Historic Conditions

The Study Area has remained an uninhabited barrier island since the destruction of

Last Island Village by a hurricane in 1856. There have been no communities or

human populations residing on the islands; hence, there is no employment or

income base. The area has supported sources of income related to oil and gas

exploration and production, and commercial and recreational fishing.

4.2.15.2.2 Existing Conditions

The Study Area is located in remote and uninhabited coastal wetlands within

Terrebonne and Lafourche Parishes. There are no communities or human

populations in the Study Area; hence, there is no employment or income base. The

area continues to support sources of income related to oil and gas exploration and

production, and commercial and recreational fishing.

4.2.15.3 Community Cohesion

There are no existing communities in the Study Area, therefore community cohesion

is not applicable.

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4.2.15.4 Environmental Justice

There are no existing communities in the Study Area, therefore environmental

justice does not appear to be a concern for this Study.

4.2.15.5 Infrastructure

4.2.15.5.1 Historic Conditions

Louisiana plays an important part in the production of natural gas and crude oil for

the Nation. Development of oil and gas resources in the Louisiana coastal zone

began in the 1920s and on the outer continental shelf (OCS) in the 1940s. In

addition to national importance, oil and gas production has played a significant role

in the States economy (USACE, 2004a).

Since 1921, the oil and gas activities in the coastal zone account for approximately

75% of all State lands leased. As these activities increased in Louisiana, the

transportation and storage of these natural resources required new infrastructure,

including pipelines for distribution from nearshore wells, to railroad facilities for

transport to processing plants. With the advent of offshore drilling, pipelines were

constructed to connect offshore oil and gas production platforms with onshore

facilities. Today, these pipeline systems extend all across coastal Louisiana in a

labyrinth consisting of nearly ten thousand miles of pipeline (USACE, 2004b).

4.2.15.5.2 Existing Conditions

As with most of the barrier islands in coastal Louisiana, the Isles Dernieres and

Timbalier Islands are unpopulated landmasses. Though some barrier islands do

contain semi-permanent populations, e.g. fishing camps and hamlets, (USDI, 2004),

Grand Isle is the only developed barrier island in Louisiana (population of 1,541;

2000 census data) (LAGIC, 2007).The Study Area continues to support oil and gas

infrastructure on the eastern end of the Isles Dernieres and majority of the

Timbalier Islands.

4.2.15.6 Business and Industry

The primary types of business and industry in the Study Area are petroleum

exploration, production, and transportation; commercial fishing, and recreational

fishing.

4.2.15.7 Traffic and Transportation

4.2.15.7.1 Historic Conditions

No transportation infrastructure has historically existed in the Study Area.

Historically, transportation to the barrier islands has been by boat.

4.2.15.7.2 Existing Conditions

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Given their disconnection from the mainland, and the lack of permanent residents,

no permanent ground transportation infrastructure exists on the Terrebonne Basin

barrier island chain. With no surface roads or railroads, and with only a few small

access canals on Trinity, Timbalier, and East Timbalier Islands, transportation to

and on the Terrebonne Basin barrier islands is limited. Transportation to the

islands is possible by boat or floatplane, while transportation on the islands is

limited to all-terrain vehicles, which are typically utilized for recreational purposes

(USEPA, 2000).

4.2.15.8 Public Facilities and Services

4.2.15.8.1 Historic Conditions

Public facilities and services were not available in the Study Area.

4.2.15.8.2 Existing Conditions

No significant public facilities or services are provided within the Study Area. The

Terrebonne Basin barrier island chain falls entirely or partially within two

conservation areas; the State-managed Isle Dernieres Barrier Islands Refuge (BIR)

and the BTES. Except for a portion of Trinity Island, access to the islands within

the BIR is restricted to surf fishing within the tidal zone (Mike Carloss, personal

communication, August, 2008).

4.2.15.9 Local Government Finance

The Study Area is located in remote and uninhabited coastal wetlands within

Terrebonne and Lafourche Parishes. Local government finance is not applicable to

this Study.

4.2.15.10 Tax Revenue and Property Values

4.2.15.10.1 Historic Conditions

The Study Area is located in remote and uninhabited coastal wetlands within

Terrebonne and Lafourche Parishes. Tax revenue and property values are not

applicable to this Study.

4.2.15.10.2 Existing Conditions

The Study Area is located in remote and uninhabited coastal wetlands within

Terrebonne and Lafourche Parishes. There are no communities or human

populations in the Study Area; hence, there are no taxable revenues or income base.

The area may support sources of income related to oil and gas exploration and

production, and commercial and recreational fishing. Whiskey, Trinity, East, and

Raccoon Islands are wholly owned by the State of Louisiana. Timbalier and East

Timbalier Islands are privately owned and subject to property taxes. Gross

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appraisals were not performed on Timbalier and East Timbalier, however,

estimated property values for these areas are approximately $500/acre.

4.2.15.11 Community and Regional Growth

4.2.15.11.1 Historic Conditions

Population densities have historically been highest in the central and northern

parts of the parish, and lowest in the southern reaches. The few isolated

communities that have developed near the GOM are typically service communities

for the oil and gas industry, or support recreational and commercial fishing

interests (USEPA, 1993).

4.2.15.11.2 Existing Conditions

In Louisiana, the Mississippi River was historically the primary means of

transportation, and its natural levees were the choice location for settlement. Over

time, the surrounding coastal lakes and adjacent lands were gradually explored for

natural resources and settlement. As the population along the Mississippi River

increased, land along its natural levees became scarce. Settlers began to move

further outward following waterways such as Bayou Lafourche, Bayou Teche,

Bayou Terrebonne, the Vermilion River, and other bayous and rivers in the coastal

area (USACE, 2004b). Similar trends were observed in Terrebonne Parish, where

migration and population concentrations occurred along waterways and adjacent

natural levees.

4.2.15.12 Land Use Socioeconomics

4.2.15.12.1 Agriculture

Historic Conditions

There are no historic agriculture uses within the Study Area.

Existing Conditions

There is no agricultural use within the Study Area.

4.2.15.12.2 Forestry

Historic Conditions

Historical information regarding forestry practices within the Study Area has not

been found during the due diligence investigations.

Existing Conditions

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There is no forestry practice conducted within the Study Area.

4.2.15.12.3 Public Lands

Historic Conditions

This resource is institutionally significantly because of the Federal Water

Protection Recreation Act of 1965, as amended; the Land and Water Conservation

Fund Act of 1965, as amended; the National Wildlife Refuge System Administration

Act of 1966; and the National Wildlife Refuge System Improvement Act of 1997.

Public lands are technically significant because of the high economic value of

recreational activities and their contribution to local, state, and national economies.

Public lands are publicly significant because of the high value that the public places

on conservation of natural resources, as well as access for fishing, hunting, and

boating activities, as measured by the large number of fishing and hunting licenses

sold in Louisiana, and the large per-capita number of recreational boat registrations

in Louisiana.

Public lands are those that are owned by the Federal or State government, which

have been made available for public access. The National Wildlife Refuge System

Improvement Act of 1997 authorized that no new or expanded use of a refuge may

be allowed unless it is first determined to be a compatible use and the use is not

inconsistent with public safety.

Existing Conditions

Terrebonne Barrier Islands Refuge (BIR) consists of three barrier islands in the

Isles Dernieres reach. Wine Island, Whiskey Island, and Raccoon Island were

acquired in June of 1992 from Louisiana Land and Exploration Company via a 25-

year free lease. The three islands comprise a total of approximately 630 acres,

although the lease agreement covers several thousand acres of water.

Except for a portion of Trinity Island, access to the islands within the BIR is

restricted to surf fishing within the tidal zone (Mike Carlos LDWF, personal

communication, August, 2008).

The reach of islands that comprise the Isles Dernieres serves as permanent and

migratory stopover habitat for shorebirds and passerine species (USEPA, 1997a). Of

the numerous waterbird nesting colonies within the Terrebonne Basin barrier

islands complex, the most significant are those found within the BIR. Raccoon

Island, which supports one of the greatest diversities of nesting and aquatic birds in

North America, contains one of the largest nesting colonies of endangered Pelecanus

occidentalis (brown pelicans) in Louisiana and a significant colony of piping plovers

(129 identified during winter census; Louisiana Coastal Wetlands Conservation and

Restoration Task Force, 2006). Just a short distance to the east, Whiskey Island

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contains some black skimmer nesting, but otherwise receives little bird usage

(USEPA, 1997a).

Management of Wine Island, on the eastern end of the Isle Dernieres reach, was

successfully reestablished in 1991 by the Louisiana Department of Natural

Resources. Bird activity on the islands is monitored by Fur and Refuge Division

staff from the Atchafalaya Delta, New Iberia, and Rockefeller Refuge. Enforcement

of rules and regulations is provided by personnel stationed at the Atchafalaya Delta

WMA.

4.2.15.13 Water Use and Supply

4.2.15.13.1 Historic Conditions

There were no historic sources of fresh water in the Study Area. Historic water use

was limited to personal consumption. Water was either transported to the Study

Area or obtained by capturing rainwater onsite with cisterns.

4.2.15.13.2 Existing Conditions

There are no onsite sources of fresh water in the Study Area. Supplies of potable

water are either transported to the Study Area or obtained by capturing rain water

onsite with cisterns.

4.2.15.14 Navigation

4.2.15.14.1 Historic Conditions

Historically as well as present, the ports and shipping lanes of coastal Louisiana

serve as vital linkages between producers and consumers throughout the Nation,

and as gateways for international trade. The navigation channels and waterways

provide for large-scale waterborne transportation of both commodities and finished

products, and an extensive network of oil and gas canals and infrastructure.

4.2.15.14.2 Existing Conditions

Within the Terrebonne Basin there is one federally maintained navigation feature

that is important to barrier island morphology, restoration, and maintenance. This

canal, the Houma Navigation Canal (HNC), serves as a navigation route connecting

the GOM with the interior of the central coast of Louisiana, providing direct access

to the maritime and offshore support interests. The HNC cuts through and provides

pathways to several natural waterways including Bayous Black, La Carpe, du

Large, Petit and Grand Caillou, Sale, and Little Cocodrie Bayou, most of which

discharge into Terrebonne Bay north of the Isles Dernieres (USACE, 2005).

These navigation channels introduce and/or compound marine influences in many of

the interior wetlands and water bodies within the coastal zone (USACE, 2004a).

The HNC has direct influence on the Terrebonne Basin barrier shoreline as its

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mouth is situated in Cat Island Pass at the western end of Timbalier Island.

Periodic maintenance dredging of the HNC also provides an opportunity for the

beneficial use of dredged material on Timbalier Island and Isles Dernieres.

However, because of the close proximity of the canal to the western end of Timbalier

Island, consideration must be given to ensure that the canal dredging does not

adversely impact the westerly longshore transport of sand. Since the islands

support limited recreational, commercial, and industrial usages, few privately

maintained channels and passes exist.

The thousands of miles of navigation channels and oil and gas canals in coastal

Louisiana have played a major role in the loss of wetlands and barrier islands

(USACE, 2004a). These losses can be attributed to the direct conversion of marsh to

open water, as well as by the indirect impacts associated with altered hydrology and

saltwater intrusion. The existing and newly constructed oil and gas canals and the

maintenance of navigation channels will continue to facilitate saltwater intrusion

into interior coastal wetlands. Salinity gradients across the coast will migrate north

and become more narrow and variable without additional inputs of freshwater from

riverine sources to hold back Gulf waters. Additionally, navigation channels that

cross open bays may silt in more rapidly or begin to shoal in less predictable ways.

Without barrier island restoration, the islands and marshes that protect waterborne

traffic will continue to erode and adversely impact vital navigable waterways. As

the adjacent and connecting protective marsh and barrier island landscapes

disappear, the wind, and wave energy from nearby open bays and the GOM will

have increased adverse effects on these navigable waterways (USACE, 2004a).

4.2.15.15 Man-Made Resources

4.2.15.15.1 Oil, Gas, Utilities, Pipelines

Louisiana plays an important part in the production of crude oil for the Nation.

Louisianas production of crude oil has declined by about 30% since 1980, although

production in the Louisiana offshore Outer Continental Shelf (OCS) has increased

steadily since 1990 and now exceeds the onshore production rate (MMS, 1999). In

2000, Louisiana produced more crude oil than any other state. Louisianas oil

resources come from wells on land, from State waters within three miles from shore,

and from Federal waters greater than three miles from shore. The amount of oil

produced by Louisiana can be put into perspective by comparing it to what is

consumed by the entire Nation. Energy consumption can be divided into five

sectors: transportation, industrial, electric power generation, residential, and

commercial. Over the past 20 years, Louisiana crude oil production alone has been

greater than what has been consumed nationally in three of these sectors:

residential, commercial, and electric power generation. Louisiana production has

increased in the past ten years so that in 2000 it produced enough crude oil to meet

the needs of all three of these sectors. Louisiana provides over 27% of the total oil

produced in the U.S. If Louisiana did not produce oil, the U.S. would have to import

30% more oil from the Organization of the Petroleum Exporting Countries (OPEC)

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than it currently does. Any significant decrease in Louisiana production would

affect citizens in all states.

Natural gas has been the second largest source of energy for the U.S. since 1988.

The United States had large natural gas reserves until the late 1980s when

consumption began to significantly outpace production. Three states (Texas,

Louisiana, Oklahoma) account for over half of all natural gas produced in the U.S.

The amount of natural gas produced by Louisiana can be put into perspective by

comparing it to what is consumed by the entire Nation in five economic sectors.

Over the past 20 years, Louisiana, gas production has been greater than what has

been consumed in four of the five sectors: transportation, commercial, electric

power, and residential sectors. Louisiana currently provides over 26% of the total

natural gas produced in the U.S. Over the past 20 years, Louisiana has produced

more natural gas than was imported by the Nation. If Louisiana did not produce

natural gas at the same level of consumption, the U.S. would have to import 133%

more gas from other countries than it currently does. Any significant decrease in

Louisianas natural gas production would have a significant impact on the U.S.

economy.

All of the oil and gas produced along Louisianas coast and wetlands comes from a

highly interdependent network of core and supporting industries. The core

businesses, along with their suppliers, contractors, services and research

departments, sprung up around each other and formed a huge cluster of business

linked to each other and to other industries throughout the region. Port Fourchon

is the geographic and economic hub of this cluster. There are hundreds of offshore

drilling rigs in the Gulf of Mexico.

The Study Area is traversed by numerous oil and gas pipelines of various sizes,

many within the footprints of the plan alternatives and in their immediate vicinity

(Figures 4-14 through 4-16).

The lines represent both a substantial investment and a substantial level of risk for

the area. The pipelines are increasingly at risk from a combination of coastal

erosion and local navigation. The erosion of wetland areas uncovers pipelines that

had been buried in the marsh for protection. As land is converted to open water, the

pipelines remain under water and unprotected from maritime traffic. Boat

collisions with the underwater pipes result in substantial losses for the industry

since collisions sometimes cause spills. With each spill, production is impacted at

both ends of the pipeline systemwhere oil is loaded, and where it is unloaded. In

addition, cleanup costs can be substantial.

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Figure 4-14. Oil and Gas Structures and Pipelines within the Terrebonne

Basin

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Figure 4-15. Potential Ship Shoal sand borrow areas and OCS

infrastructure (MMS 2004)

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Figure 4-16. The proposed South Pelto sand borrow area and OCS

infrastructure (MMS 2004)

4.2.15.15.2 Flood Control and Hurricane Protection

Historic Conditions

No flood control or hurricane protection features have historically existed in the

Study Area.

Existing Conditions

The Study Area does not contain any flood control or hurricane protection

structures. The closest flood control or hurricane protection measure is located in

Chauvin, Louisiana.

4.2.15.16 Natural Resources

4.2.15.16.1 Commercial Fisheries

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Historic Conditions

Louisiana has five main commercial fishing ports located on main waterway

arteries leading from the GOM. These ports are located in: 1) Empire-Venice area

along the Mississippi River with main access to the Gulf through the Empire

Waterway and Tiger Pass; 2) Dulac-Chauvin area in Terrebonne Parish with main

access to the Gulf through the Houma Navigation Canal; 3) Morgan City-Berwick

area along the Atchafalaya River; 4) Intracoastal City on the west side of Vermillion

Bay; and 5) Cameron in southwest Louisiana along the Calcasieu River. The

seafood industry in south Louisiana is based primarily on the harvesting of white

and brown shrimp, crabs, oysters, and menhaden.

In terms of dockside revenue, the shrimp is the most important commercially

landed marine species in Louisiana. Since 1976, shrimp landings in Louisiana have

ranged from a low of approximately 49 million pounds (heads-off weight) in 1983, to

a high of approximately 93 million pounds in 1986. In 2006, the total weight (headson) of shrimp landed in Louisiana was approximately 137 million pounds, had a

value of more than $147 million, and accounted for more than 47% of the United

States total (LDWF, 2008c).

Existing Conditions

Louisiana produced about 52.8 million pounds of blue crabs, totaling $31.8 million

in dockside revenue, and accounting for 36% of the Nations total production for

2006 (LDWF, 2008c). Since 1976, Louisiana has experienced significant increases in

blue crab landings. These landings, which have ranged from a low of approximately

15 million pounds in 1973, to a high of approximately 52 million pounds in 2006,

have resulted in Louisiana becoming one of the largest producers of blue crabs in

the Nation (LDWF, 2008c). These trends in blue crab landings have allowed

Louisiana to surpass the dominant producing states of the 1990s (USACE, 2004b).

Landings of most fish species are expected to vary somewhat from year to year

depending on naturally varying environmental conditions. One of the most

important species harvested in the Louisiana waters is the Gulf menhaden. This

species of fish is primarily processed for both fishmeal and fish oil. Fishmeal is used

as a high protein animal feed. The broiler (chicken) industry is currently the largest

user of menhaden meal, followed by the turkey, swine, pet food, and ruminant

(cattle/livestock) industries. The 2006 Louisiana menhaden fisheries landings were

the largest in the Nation (746 million pounds; LDWF, 2008c), landing twice as much

as the next closest state. The percent of dockside value from Louisiana to that of the

rest of the Nation was over 57% (USACE, 2004b).

Louisiana also has led the United States in eastern oyster production, contributing

just under half of the U.S. production. In 2006 alone, Louisiana had 58% of the

Nations eastern oyster landings (approximately 11.5 million pounds; LDWF,

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2008c), and 49% (approximately $36 million; LDWF, 2008c) of the Nations eastern

oysters dockside value (USACE, 2004b).

Located just north of the Study Area, the port at Dulac-Chauvin, Louisiana,

reported commercial fisheries landings in 2007 at 23.5 million pounds with a

dockside value of 35.5 million dollars (NMFS, 2008).

Commercial landings (dockside value) of fish and shellfish, including freshwater

fish, in Louisiana are presented in Figure 4-17 (source: (LDWF, 2008). Fluctuations

in year to year landings can be caused by a variety of factors including winter

freezes, drought, tropical storms, and transportation costs, and usually do not

indicate long-term environmental problems. Individual organisms produce large

numbers of eggs, so populations can recover quickly from short-term detrimental

conditions. However, long-term (3 years or more) declines in landings can signify

that there are ongoing environmental problems and/or over-fishing of the resource,

or a weakening market. The main environmental problem would be the

disappearance of estuarine marsh nursery areas. Remaining areas can not support

as many young. Table 4-12 contains the marine commercial landings data for 2006

provided by the LDWF, divided into individual species of shellfish and finfish

(LDWF, 2008).

Figure 4-17. Marine Commercial Landings Dockside Value Louisiana 1990-

2005. (LDWF, 2008)

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Table 4-12. 2006 Marine Commercial Landings. (LDWF, 2008)

4.2.15.16.2 Oyster Leases

Historic Conditions

In 1892, Louisiana Act 206 established the first public oyster grounds open to all

Louisiana residents. Act 206 also adjusted the closed season, increased the size of a

lease to ten acres (4 ha), and authorized the office of oyster inspector to enforce the

laws. Ten years later, Louisiana's first comprehensive oyster law was passed with

the Act of 1902. The Louisiana Department of Conservation issued the first private

oyster lease in 1903 in Plaquemines Parish (Laiche, 1993). Additionally, the State

manages several oyster seed grounds, from which oysters can be collected for

transfer to private leases.

Oysters have been harvested in Louisiana for commercial sale for at least 150 years.

The Louisiana oyster industry has been experiencing many stressors over the past

several decades that threaten the long-term sustainability of both the industry and

the resource. Increasing coastal land loss is reducing the amount of marsh that

provides shelter to oyster reefs, and saltwater intrusion is exacerbating disease and

predation. In addition, the industry is faced with changing environmental

conditions, fluctuating market demands, public perception issues, and increased

competition.

Oyster lease acreage in Terrebonne Parish steadily increased between 1959-60 and

2002 and then exhibited minor decreases to 2005. Lafourche Parish oyster lease

acreage steadily increased between 1959-60 to 2001 and has steadily decreased to

2005.

Existing Conditions

Terrebonne and Lafourche parish play an important role in Louisianas oyster

industry, accounting for more than 25% of the States total oyster leases (by area;

Table 4-13). Within 6 kilometers of the Study Area, there are approximately 100

oyster leases. These leases are most plentiful to the north of the Isles Dernieres

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reach, in the northern portions of Caillou Bay and Lake Pelto. Locations of oyster

leases in the Study Area are shown on Figure 4-11 in section 4.2.9.2. Though there

are many leases in the Isles Dernieres vicinity, few leases are located near the

Timbalier Island Reach. Nearby seed grounds are managed by the LDWF to

produce a ready supply of seed oysters that can be planted on private leases for

later harvest. The oyster lease acreage in Terrebonne and Lafourche Parishes is

presented in Table 4-13. Oyster leases have been a serious constraint on conducting

coastal restoration since the beginning of early coastal restoration efforts in the

1990's.

The Gulf region led the U.S. in oyster production in 2007 with 22 million pounds of

meats, 63% of the national total (NMFS, 2008). In Louisiana, a total of 12.8 million

pounds of oyster were harvested in 2007, with a value of $40.1 million (NMFS,

2008). Production of oysters in Louisiana has been relatively stable for the last 50

years, with harvest from public beds replacing the decreasing harvest from private

leases. However, increasing coastal land loss is reducing the amount of marsh that

provides shelter to reefs, and saltwater intrusion is exacerbating disease and

predation.

Oysters have been harvested in Louisiana for commercial sale for at least 150 years

and provide an important resource in the Terrebonne Basin. Oyster leases have

been a serious constraint on conducting coastal restoration since the beginning of

early coastal restoration efforts in the 1990's (USACE, 2009). Natural coastal

processes will at times migrate island footprints over or near existing oyster leases.

For the longevity of the restoration to reach the Study goals the design template

may be enlarged and therefore encompass existing oyster leases. The proximity of

the oyster leases to the construction activities should always be considered during a

restoration projects such that the sediment plumes from dredging and dewatering

do not adversely affect the health of the oysters. Typically oyster leases that could

be affected by such activities would be mitigated following the design of the

restoration project. The oyster lease acreage in Terrebonne and Lafourche Parishes

is presented in Table 4-13.

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Table 4-13. Oyster lease acreage in Terrebonne and Lafourche Parishes.

(source: http://oysterweb.dnr.state.la.us/oyster/oystertable.htm)

Year

Terrebonne

Parish

Lafourche

Parish

Louisiana Total

Acres

Average

change per

year

Acres

Average

change per

year

Acres

Average

change per

year

1959-60 19,127 5,827 73,591

1969-70 22,539 (+) 341.2 11,535 (+) 570.8 138,837 (+) 6,524.6

1975-76 33,012 (+) 1,745.5 12,951 (+) 236.0 193,225 (+) 9,064.7

1976-77 38,781 (+) 5,769.0 15,157 (+) 2,206.0 213,411 (+) 20,186.0

1977-78 44,762 (+) 5,981.0 17,340 (+) 2,183.0 231,909 (+) 18,498.0

1978-79 43,284 (-) 1,478.0 18,456 (+) 1,116.0 237,946 (+) 6,037.0

1979-80 41,265 (-) 2,019.0 15,689 (-) 2,767.0 228,960 (-) 8,986.0

1980-81 42,595 (+) 1,330.0 15,657 (-) 32.0 231,762 (+) 2,802.0

1981-82 43,025 (+) 430.0 15,119 (-) 538.0 236,331 (+) 4,569.0

1988-89 51,813 (+) 1,255.4 16,930 (+) 258.7 328,269 (+) 13,134.0

1990-91 53,530 (+) 858.5 18,870 (+) 970.0 345,394 (+) 8,562.5

1991-92 55,033 (+) 1,503.0 17,851 (-) 1,019.0 356,711 (+) 11,317.0

1992 61,331 (+) 6,298.0 17,528 (-) 323.0 359,902 (+) 3,191.0

1997 81,664 (+) 4,066.6 21,158 (+) 726.0 378,747 (+) 3,769.0

1998 89,247 (+) 7,583.0 21,951 (+) 793.0 397,916 (+) 19,169.0

1999 88,886 (-) 361.0 22,356 (+) 405.0 403,141 (+) 5,225.0

2000 92,385 (+) 3,499.0 26,277 (+) 3,921.0 415,459 (+) 12,318.0

2001 93,661 (+) 1,276.0 27,402 (+) 1,175.0 419,900 (+) 4,441.0

2002 93,858 (+) 197.0 26,228 (-) 1,174.0 419,091 (-) 809.0

2003 92,711 (-) 1,147.0 24,891 (-) 1,337.0 409,209 (-) 9,882.0

2004 92,548 (-) 163.0 24,802 (-) 89.0 397,892 (-) 11,317.0

2005 92,023 (-) 525.0 23,706 (-) 1,096.0 392,763 (-) 5,129.0

2006 91,890 (-) 133.0 23,448 (-) 258.0 392,118 (-) 645.0

Oyster lease acreage in Terrebonne Parish steadily increased from 1959 to 1978.

The Parish experienced a decrease from 1979 to 1980 followed by a relatively steady

increase until 2003. Following 2003, Terrebonne Parish begins to have a decline in

acreage each year.

Oyster lease acreage in Lafourche Parish steadily increased from 1959 to 1979.

From 1980 to 1997 the oyster lease acreages fluctuate at which time Lafourche

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Parish experiences increasing levels until 2002. This growth slows and by 2002

begins to decline in acreage each year.

In comparison to Terrebonne and Lafourche Parish, the overall acreages for the

State continually increase from 1959 to 2001 except for the 1979-80 season.

Following 2001 the oyster lease acreage totals begin to decline with a sharp

decrease in 2004.

4.2.16 Hazardous, Toxic, and Radioactive Wastes

A Phase I Environmental Site Assessment of the Study Area was conducted and

recorded in HTRW Phase I Environmental Site Assessment, Terrebonne Basin

Barrier Shoreline Restoration Project, Contract No. 2503-07-15 for Coastal

Protection and Restoration Authority.

The purpose of this Phase I ESA is to identify historical or overt physical evidence

of current or past activities or materials at the Site and its immediate vicinity

which constitute "recognized environmental conditions,"(RECs) defined by the

ASTM Standard to be "the presence or likely presence of any hazardous, toxic, and

radioactive substances or petroleum products on a property under conditions that

indicate an existing release, a past release, or a material threat of a release into

structures on the property or into the ground, groundwater, or surface water of the

property."

This Phase I ESA is consistent with the Scope of Work (SOW) provided by the Corps

of Engineers and protocols established in the American Society for Testing and

Materials publication "Standard Practice for Environmental Site Assessments:

Phase I Environmental Site Assessment Process for Forestland or Rural Property"

(Designation E 2247-08, referred to as the ASTM Standard) to provide "due

diligence" for rural transactions. However, this report will require a second site visit

and interviews related to ASTM Standard to be conducted at a later date that is

closer to expected time of construction for the year 2012.

On November 20, 2008, SJBs environmental specialists performed an aerial site

reconnaissance of the subject property and its adjacent properties and a field visit

on July 27-30th, 2009 at selected locations throughout the Study Area. The Site is

currently Terrebonne Basin Barrier Shoreline consisting of seven major barrier

islands that include: East Timbalier Island, Timbalier Island, Wine Island, East

Island, Trinity Island, Whiskey Island, and Raccoon Island. Photographs were

taken documenting field observations and are included in this report.

SJB obtained historical documentation of the Sites past uses and activities in order

to identify possible recognized environmental conditions. Sources of historical

documentation for this report included historical aerial photographs, topographic

maps, and Environmental Database Report.

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SJB has performed a Phase I Environmental Site Assessment on Isle Dernieres and

the Timbalier Island reach, located within Terrebonne Basin in Terrebonne Parish,

Louisiana (the Site). Any exceptions to or deletions from this practice are described

in section 2.4 of this report. Based upon historical sources, environmental database

reviews, and a limited Site inspection, at this time SJB did not identify any current

Recognized Environmental Conditions, or any historical Recognized Environmental

Conditions that would affect the proposed project. The Emergency Response

Notification System (ERNS) records six spills (see appendix) of petroleum products

in the Study Area. These incidents are historical Recognized Environmental

Conditions (RECs), but would not affect the proposed project.

There are numerous oil and gas production facilities and pipelines in the Study

Area; these are the most likely locations where Recognized Environmental

Conditions might be found. Because of the large number of wells and pipelines in

the area a site visit to each would be impracticable; however, the area has been

physically surveyed by water and air, and relevant databases have been consulted.

No Recognized Environmental Conditions were found, but these wells and pipelines

deserve continuing vigilance, both up to and during construction.

Based on historical sources that were provided dating back to the late 1800s,

environmental database reviews, and a limited Site inspection, SJB can not

adequately identify any current and historical recognized environmental conditions

as defined in ASTM standard E 2247-08 at this time. A more in depth site visit and

interviews with people knowledgeable of the Site history will be conducted closer to

the expected construction time.

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5.0 ENVIRONMENTAL CONSEQUENCES

This chapter describes the potential environmental consequences of implementing

alternative plans considered for restoration of the Terrebonne Basin Barrier

Shoreline. The prefatory description of the importance of the barrier islands to the

ecological and socioeconomic fabric of Louisiana that is contained in §4.2.15 is

equally relevant and pertinent to the discussion of the Environmental

Consequences of the restoration of the Terrebonne Basin Barrier Shoreline. One

must be cognizant of the complex of interrelationships involving the living and

mineral natural resources of coastal Louisiana, the changing geographic

morphology of the region, and the people who depend on the area for their

livelihood. This awareness should be in the forefront as one studies the following

analysis, which compares the No Action Alternative (Future Without Project

Conditions) to five alternatives carried over from the final array.

Alternative 2: Timbalier (Plan E)

Alternative 3: Whiskey (Plan C)/Timbalier (Plan E)

Alternative 4: Whiskey (Plan C)/Trinity (Plan C)/Timbalier (Plan E)

Alternative 5 (NER Plan): Raccoon with TG (Plan E)/Whiskey (Plan

C)/Trinity (Plan C)/Timbalier (Plan E)

Alternative 11: Whiskey (Plan C with renourishment)

These alternatives were carried forward for detailed analysis because they were all

cost effective and fell along the efficient frontier curve. Alternatives 6, 7, 8, 9, and

10 were not cost effective and therefore, not carried forward for further analysis.

Alternative 9 was also removed from further analysis because the cost per AAHU

was significantly (14%) higher than Alternative 2 and it fell above the efficient

frontier curve.

The recommended component of construction was developed by considering the best

combination of restoration plans that would meet the study objectives. All

restoration alternatives considered during the alternative plan formulation process

are described in more detail in Section 3.3.

The environmental analysis includes comparison of the potential direct, indirect,

and cumulative impacts. Direct impacts are those effects that are caused by the

action and occur at the same time and place (40 CFR 1508.8(a)). For example,

unavoidable effects on fish and wildlife from the placement of dredged material to

restore/create barrier shoreline. Indirect impacts are those effects that are caused

by the action and are later in time or further removed in distance, but are still

reasonably foreseeable (40 CFR 1508.8(b)). For example, the reduction in hurricane

storm surge that indirectly results from restoration/creation of the barrier system of

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shorelines, headlands, and islands and salt marsh. Cumulative impacts are the

effects on the environment that result from the incremental impact of the action

when added to other past, present, and reasonably foreseeable future actions,

regardless of what agency (Federal or non-Federal) or person undertakes such

actions. Cumulative impacts can result from actions that individually are minor,

but collectively result in significant actions taking place over time (40 CFR 1508.7).

For example, the incremental impacts of barrier island restoration at several areas

throughout the basin, could, collectively, significantly modify an entire basins

barrier system. The cumulative impact analysis followed the 11-step process

described in the 1997 report by the Council of Environmental Quality entitled

Considering Cumulative Effects Under the National Environmental Policy Act.

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Table 5-1. Comparison of Cumulative Impacts*

SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Soil Resources

US, LA & SA: Naturalprocesses of parent material,climate, organisms, relief, time,waves, runoff, and other factorsin soil formation and soil loss.Institutional recognition ofimportance of soil resourceswith formation of SoilConservation Service, later tobecome Natural ResourcesConservation Service. Upstreamdams, locks, and reservoirs,become sinks for sedimentscarried by Mississippi River.Leveeing Mississippi River andtributaries eliminates seasonaloverflows of sediment-ladenwaters responsible for soilbuilding in deltaic plain.

US: Continued institutional recognition.Human activities (population growth,agriculture, industry, etc.) continueimpacting natural processes of soil formationand soil loss. Soil conservation measures andconstruction of levees, dams, locks, andother structures reduces sediment loads inMississippi River and tributaries.LA: Louisiana coastal land loss of over1,900 square miles (492,097 ha) since the1930s. Total of about 6,337 acres (2,564 ha)barrier habitat restored with beneficial use ofdredged material (746 acres [302 ha]) andCWPPRA restoration projects (5,591 acres[2,262 ha]).SA: LCA TBBSR Study Area is currentlylosing soil resources at a mean rate of 57ft/yr.

US: Continued institutionalrecognition. Continued humanactivities and resultantdegradation and loss of soilresources.LA: Continued coastal land losswith prediction of 328,000 acres(13,284 ha) lost over the next 50years.SA: Continued barrier islandhabitat loss with 3,227 acres ofsoil resources from all sevenislands predicted to be lost overnext 50 years, leaving only 6acres of intertidal habitat at twoislands beyond TY50.

US: Continued institutional recognition. Continued degradationand loss of soil resources. Continued technical assistance andcost-sharing programs for soil conservation to reduce soil losses.LA: Without a comprehensive coast wide coastal restorationeffort, coastal land loss would continue with prediction of nearly328,000 acres (13,284 ha) loss over the entire Louisiana coastalarea by 2050. Implementing the NER PLAN with renourishmentwould result in a modest increase of soil resources.A5 (NER Plan): restore net total of 2,760 acres barrier soilresources.A11: restore net total of 527 acres barrier soil resources.

A2: restore net total of 1,311 acres barrier soil resources.

A3: restore net total of 1,838 acres barrier soil resources.

A4: restore net total of 2,119 acres barrier soil resources.

*Cumulative impact analysis follows the 11-step process described in the 1997 report by the Council of Environmental Quality entitled “Considering Cumulative Effects Under the National

Environmental Policy Act." Includes Spatial/Geographic Extent (Continental United States [US], Louisiana [LA}, and Study Area [SA]; and Temporal (Past, Present, and Future WithoutProject). Identifier Code: A2, A3, A4, A5, and A11= Terrebonne Basin Barrier Island Restoration (TBBSR) Feature 2, 3, 4, 5 and 11 respectively; NER = National Ecosystem Restoration Plan.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Offshore,

Nearshore, and

Riverine Sand

Resources

US, LA & SA: Naturalprocesses of longshoretransport, erosion, tides, etc.,build and deplete offshore sanddeposits. Institutionalrecognition of importance ofresources with creation ofMMS.

US & LA: Continued institutionalrecognition. MMS establishes LouisianaSand Management Working Group to bettermanage offshore sand resources. Naturalprocesses and human activities continue tobuild and deplete sand deposits.SA: Continued oil, gas, and mineralexploration and extraction activities on ShipShoal and other offshore and nearshore sandresource areas. Nearshore and riverine sandresources continued to be utilized for fill inconstruction and civil works projects.

US & LA: Continuedinstitutional recognition. Naturalprocesses and human activitiescontinue to build and depleteoffshore sand deposits.Increased competition foroffshore and nearshore areasespecially for oil and gasexploration.SA: Large areas of the offshoresand shoals (Ship Shoal) andnearshore sand bodies wouldlikely continue to remain largelyundisturbed from dredging orother mining efforts, except foroil and gas exploration andextraction activities. Continue toutilize riverine sand resourcesfor fill in construction and civilworks projects. Upstream soilconservation practices wouldlikely continue resulting indecrease of available sedimentsto replenish sediment borrowsites.

US & LA: Continued institutional recognition. Natural processesand human activities continue to build and deplete offshore sanddeposits. Increased competition for offshore areas especially foroil and gas exploration. Continue to utilize riverine sandresources for fill in construction and civil works projects.Upstream soil conservation practices would likely continueresulting in decrease of available sediments to replenish sedimentborrow sites. Implementing the NER Plan would result in acomparatively small reduction to offshore sand resources.A5 (NER Plan): removal of 79,427,267 CY of borrow material.A11: removal of 26,940,249 CY of borrow material.A2: removal of 24,027,311 CY of borrow material.A3: removal of 50,967,560 CY of borrow material.A4: removal of 65,623,620 CY of borrow material.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Barrier

Systems:

Barrier

Shorelines,

Headlands, and

Islands

US & LA: Barrier systemsnaturally build and erodedependent on deltaic cycle andother geomorphic processes.Institutional recognition(Coastal Barrier Resources Actof 1990). Increased floodcontrol (especially leveeing) ofMississippi River andtributaries following 1927regional flooding furtherdisrupts deltaic cycle andbarrier system building incoastal Louisiana.SA: Construction of navigationchannels, jetties, oil and gasexploration and access canals,and other structures along gulfshoreline alters longshoretransport and sedimentavailability for land buildingprocesses.

US: Continued institutional recognition.Barrier systems continue building anderoding depending on human disruptions ofnatural geomorphic processes.LA: Continued disruption of deltaic cycleand longshore transport prevents rebuildingof barrier systems; increased stormfrequency resulting in net losses of allLouisiana coastal barrier systems. Averagerate of long-term (> 100 years) shorelinechange is –19.9 ft/yr (6.1 m/yr). Averageshort-term rate (< 30 years) of shorelinechange is 30.9 ft/yr (9.4 m/yr). Total of about6,337 acres (2,564 ha) barrier habitatrestored with beneficial use of dredgedmaterial (746 acres [302 ha]) and CWPPRArestoration projects (5,591 acres [2,262 ha]).SA: Annual average land loss of theTerrebonne Basin Barrier Shoreline is56.9 ftper year.

US: Continued institutionalrecognition. Barrier systemscontinue building and erodingdepending on human disruptionsof natural geomorphic processes.LA: Continued disruption ofdeltaic cycle and longshoretransport prevents rebuilding ofbarrier shorelines, headlands,and islands; continued increasedstorm frequency results insignificant loss of many barrierislands and shorelines.SA: Continued barrier islandhabitat loss with 3,227 acres ofsoil resources from all sevenislands predicted to be lost overnext 50 years, leaving only 6acres of intertidal habitat at twoislands beyond TY50.

US & LA: Continued institutional recognition. Barrier systemscontinue building and eroding depending on human disruptionsof natural geomorphic processes; continued disruption of deltaiccycle and longshore transport prevents rebuilding of barriershorelines, headlands, and islands; continued increased stormfrequency results in significant loss of many barrier islands andshorelines. Implementing the NER with renourishment wouldresult in a modest increase of soil resources.A5 (NER Plan): restore net total of 2,760 acres of barrier soil

resources.A11: restore net total of 527 acres barrier soil resources.A2: restore net total of 1,311 acres barrier soil resources.

A3: restore net total of 1,838 acres barrier soil resources.

A4: restore net total of 2,119 acres barrier soil resources.

Coastal

Processes

US, LA, & SA: Natural coastaland Mississippi River and itstributaries processes oflongshore transport, erosion,tides, etc., build and depletebarrier systems. Institutionalrecognition of importance ofresources with creation ofMinerals Management Service.

US & LA: Natural coastal and MississippiRiver and its tributaries processes oflongshore transport, erosion, tides, etc., buildand deplete barrier systems. Institutionalrecognition of importance of resources withcreation of Minerals Management Service.SA: As barrier land loss continues,hydrologic connections between the gulf andinterior areas increase and exacerbate interiorland loss and conversion of habitat types.Continued loss of barrier systems result inreduction and loss of the natural protectivestorm buffering of these barrier systems

US & LA: Natural coastal andMississippi River and itstributaries processes oflongshore transport, erosion,tides, etc., build and depletebarrier systems. Institutionalrecognition of importance ofresources with creation ofMinerals Management Service.SA: similar to existingconditions.

US & LA: Similar to no action alternatives (FWOP)A5 (NER): Restoration of four barrier islands, combined withinterior marsh creation and restoration measures, would widenthe islands sufficiently to prevent breach formation, therebyreducing formation of additional tidal passes, as well as closingexisting breaches and over wash areas. An undeterminedreduction in tidal prism would also result. These differentrestoration measures would act together to retard saltwaterintrusion into more northern portions of the Terrebonne Basin.A11: a single island version of A5.A2: a single island version of A5.A3: a two island version of A5.A4: a three island version of A5.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Salinity

Regimes

US: Geomorphic and marineprocesses influence the tidalprism and salinity regimes.LA & SA: Salinity regimes insubprovinces naturally fluctuatein response to deltaic cycle,geomorphic and marineprocesses, as well as othernatural factors influencing thetidal prism.

US: Natural and human disruption ofgeomorphic and marine processes modifytidal prisms, influence salinity regimes, andfacilitates saltwater intrusion into upperestuaries.LA: Human disruption of the deltaic cycleand geomorphic and marine processes,including construction of navigation and oiland gas access channels, modifies tidal prismand resulting in saltwater intrusion andhigher salinities within interior portions ofestuaries.SA: Continued land loss, increases in thenumber of in tidal inlets, disruption of thetidal prism, and conversion of barrier habitatand saline marsh habitat to open water alterssalinity regimes.

US: Continued natural andhuman disruption of geomorphicand marine processes modifytidal prisms, influence salinityregimes, and facilitate saltwaterintrusion into upper estuaries.LA: Continued humandisruption of deltaic cycle andother geomorphic and marine

process allow saltwater intrusion

into upper estuaries; navigationand oil and gas canals/channelscontinue to facilitate saltwaterintrusion.SA: Continued land loss,increased breaching, andincrease in numbers of tidalinlets, disruption of the tidalprism, and conversion to openwater alters salinity regimes.

US & LA: Continued natural and human disruption ofgeomorphic and marine processes modify tidal prisms, influencesalinity regimes, and facilitate saltwater intrusion into upperestuaries. Continued human disruption of deltaic cycle and othergeomorphic and marine processes that allows saltwater intrusioninto upper estuaries; navigation and oil and gas canals/channelscontinue to facilitate saltwater intrusion. Implementing the NERwould result in a comparatively small reduction to the humanperturbations and disruption of salinity regimes.A5 (NER): Implementation would result in little, if any impactson salinity regimes.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Water Quality

US, LA & SA: Degradedwaterbodies due to untreatedand uncontrolled discharges,especially in urbanized and/orindustrialized areas. Enactmentof Federal and State legislation(e.g. Clean Water Act)beginning in the 1970s torestore and protect waterbodies,especially with respect to pointsources.

US: Continued institutional regulation.Nonpoint sources unregulated. According tothe National Water Quality Inventory 2000Report about 39 percent of streams, 45percent of lakes, and 51 percent of estuariesassessed were not clean enough to supportuses such as fishing and swimming).LA: Hurricane Katrina (2005) causes 10major oil spills and 35 minor oil spills (totalof 7,340,990 gallons) in southeast Louisianahttp://www.laseagrant.org/hurricane/oil.htm).SA: 53,000-gallon oil spill from Chevronfacility at Port Fourchon (source:http://www.laseagrant.org/hurricane/oil.htm).

US, LA & SA: ContinuedPresent Action.LA & SA: Increasing potentialfor accidental discharges due toexposed infrastructure becauseof coastal land loss.

US & LA: Continued Federal and State programs that requireand/or encourage protection of waterbodies.A5 (NER): Short term and minor water quality impacts primarilyduring construction e.g., increased turbidity, decreased DOassociated with placement of dredged material.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Vegetation

Resources

US, LA & SA: Naturalprocesses form vegetatedbarrier habitats and coastalwetlands. Institutionalrecognition of coastal barrierresources and wetlands (e.g.,Coastal Barrier Resource Act,Estuary Protection Act, andothers).LA: Accelerated deteriorationand loss of Louisiana coastalwetlands of over 1.22 millionacres (485,830 ha) since the1930s.

US & LA: Continued institutionalrecognition. Natural processes such assubsidence, wave erosion, as well as humanactivities causes deterioration and loss ofvegetated barrier and wetland habitat.SA: the individual islands of the TerrebonneBasin Barrier Shoreline are losing vegetatedwetlands at varying rates. By target year 50the islands will have lost all upland area anda total of 1,560 acres of vegetated wetlandhabitat. The two remaining islands will berepresented only by 2 and 4 acres ofvegetated wetland.

US: Continued institutionalrecognition. Continued loss ofwetlands and vegetative acreagedue to natural processes andhuman activities.LA: Continued accelerated coastwide loss vegetated barrierssystems. Most severe loss inNation.SA: Land loss rates continuesimilar to existing conditions.

US: Continued institutional recognition. Continued loss ofvegetative acreage due to natural processes and development.Implementing recommended component of construction wouldresult in a comparatively small reduction to the rate of loss ofvegetation habitat.LA: Continued accelerated coast wide loss of vegetated barrierssystems; most severe loss in Nation. Implementing the NERwould result in a significant increase in the area of vegetatedhabitat.A5 (NER): Net total of 1459 acres of vegetated barrier habitatsrestored. Plantings of native species increase important andcritical vegetated habitats used by fish and wildlife.A11: similar to NER except a net total of 311 acres.A2: similar to NER except a net total of 706 acres.A3: similar to NER except a net total of 1,117 acres.A4: similar to NER except a net total of 1,120 acres.

Wildlife

Resources

US, LA & SA: Vast expanses of

coastal wetlands and barriersystems provide diversity ofhabitats that enable wildlifepopulations to respond tonatural population-regulatingmechanisms. Institutionalrecognition of importance ofresource with creation of U.S.Fish and Wildlife Service.Coastal land loss of over1,900 square miles (492,097 ha)since the 1930s, most of whichwere suitable wildlife habitats.

US, LA & SA: Continued land loss results indecline and loss of suitable wildlife habitats;increased interspecific and intraspecificcompetition for decreasing habitats.LA: About 6,337 acres (2,564 ha) of barrierhabitat restored with beneficial use ofdredged material (746 acres [302 ha]) andCWPPRA restoration projects (5,591 acres[2,262 ha]) most of which were suitablewildlife habitats.SA: Terrebonne Basin Barrier Shoreline iscurrently losing wildlife habitat at a meanrate of 57 ft/yr.

US, LA, & SA: Continued landloss results in decline of suitablehabitats and increasedinterspecific and intraspecificcompetition for decreasinghabitats.SA: By TY50, the LCA TBBSRStudy could lose 3,221 acres ofwildlife habitats from all but twoof the islands, which wouldretain 6 acres of intertidalwetland.

US & LA: Continued land loss results in decline of suitablewildlife habitats and increased interspecific and intraspecificcompetition for decreasing habitats.Implementing the NER would result in an increase in suitablewildlife habitats, which should be a positive impact to wildlifepopulations.A5 (NER): Restore a total of 2738.6 AAHUs for a net total of2760 acres of important and essential vegetated habitats used bywildlife for shelter, nesting, feeding, roosting, cover, migratoryneotropical bird stopover habitat, nursery, and other liferequirements.A11: similar to NER except restore a total of 557.9 AAHUs anda net total of 527 acresA2: similar to NER except a total of 1,206.6 AAHUs and a nettotal of 1,311 acresA3: similar to NER except a total of 1,764.5 AAHUs and a nettotal of 1,800 acresA4: similar to NER except a total of 2,268.3 AAHUs and a nettotal of 2382 acres.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Fisheries

Resources

US: Fisheries habitats generallyreduced, while catch increased.Institutional recognition withcreation of National MarineFisheries Service.LA & SA: Disruption of deltaiccycle; reduction insustainability of fisherieshabitat, while access (marshedge) increased; increasedproductivity and catch.

US: Regulated catch; habitat loss decreasedby coastal restoration efforts, continued nethabitat loss. Institutional recognition ofessential fish habitat.LA: Total of about 6,337 acres barrier habitatrestored with beneficial use of dredgedmaterial (746 acres) and CWPPRArestoration projects (5,591 acres) restoresvarious fishery habitats (e.g., nursery habitat,and other).LA & SA: Sustained to increasingpopulations of fish resources. However, nowexperiencing loss of essential fish habitat,especially barrier habitats and coastalwetlands that function as nursery.

US, LA & SA: Continued lossand degradation of essential fishhabitat; net loss in fisheriespopulation size and diversity.

US & LA: Continued loss of essential fish habitat; net loss infisheries population size and diversity. Implementing the NERwould result in a comparatively small improvement, nationwide,in fisheries populations and diversity.A5 (NER): Net total of 2,097 acres of intertidal estuarine habitatsused for spawning, nursery, nesting, and foraging bycommercially and recreationally important species of finfish andshellfish, as well as other aquatic organisms.A11: similar to NER except a net total of 363 acres.A2: similar to NER except a net total of 1,075 acres.A3: similar to NER except a net total of 1,438 acres.A4: similar to NER except a net total of 1,629 acres.

Essential Fish

Habitat

(EFH)

US, LA & SA: Institutionalrecognition of the decline inessential fish habitat(Magnuson-Stevens FisheryConservation and ManagementAct). General decrease inquality and quantity of essentialfish habitat.

US: Continued institutional recognition.Continued degradation and loss of essentialfish habitat.LA: Total of about 6,337 acres barrier habitatrestored, or authorized for restoration withbeneficial use of dredged material (746acres) and CWPPRA restoration projects(5,591 acres) restores essential fish habitats.SA: Barrier habitat and coastal wetlandlosses leads to loss and degradation ofessential fish habitat.

US, LA & SA: Continuedinstitutional recognition.Continued degradation and lossof essential fish habitat.

US & LA: Continued degradation and loss of essential fishhabitat. Implementing the NER would result in a comparativelysmall improvement, nationwide, in essential fish habitat.A5 (NER): Net total of 2,097 acres of intertidal estuarine habitatsused for spawning, nursery, nesting, and foraging bycommercially and recreationally important species of finfish andshellfish, as well as other aquatic organisms.A11: similar to NER except a net total of 363 acres.A2: similar to NER except a net total of 1,075 acres.A3: similar to NER except a net total of 1,438 acres.A4: similar to NER except a net total of 1,629 acres.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Water Bottoms

and Benthic

Resources

US, LA & SA: The benthiccommunity is a storehouse oforganic matter and inorganicnutrients, as well as a site formany vital chemical exchangesand physical interactions.Benthic populations respond tonatural population-regulatingconditions such as predation,sediment characteristics,salinity regimes, position in theintertidal zone, and oxygenlevels.

US: The benthic community is a storehouseof organic matter and inorganic nutrients, aswell as a site for many vital chemicalexchanges and physical interactions. Benthicpopulations respond to natural and humaninduced perturbations to aquatic habitats.LA & SA: Benthic populations of salinetolerant species become more prevalent ininterior and upper portions of subprovincesas land loss and saltwater intrusioncontinues.

US: The benthic community is astorehouse of organic matter andinorganic nutrients, as well as asite for many vital chemicalexchanges and physicalinteractions. Benthic populationscontinue to respond to naturaland human-inducedperturbations to barrier systems.LA & SA: Benthic populationsof saline-tolerant speciescontinue to become moreprevalent in interior and upperportions of subprovinces as landloss and saltwater intrusioncontinues.

US & LA: The benthic community is a storehouse of organicmatter and inorganic nutrients, as well as a site for many vitalchemical exchanges and physical interactions. Benthicpopulations continue to respond to natural and human-inducedperturbations. Implementing the NER would result in acomparatively small reduction, nationwide, to the predominanceof saline-tolerant populations.A5(NER): 79,427,267 cy borrow material required that directlyimpacts a total of 4,086 acres of water bottomsA11: 26,940,249 cy borrow material required that directlyimpacts a total of 1,394 acres of water bottomsA2: 24,027,311 cy borrow material required that directly impactsa total of 1,260 acres of water bottomsA3: 50,967,560 cy of borrow required that directly impacts atotal of 2,654 acres of water bottomsA4: 65,623,620 cy of borrow required that directly impacts atotal of 3,412 acres of water bottoms.

Plankton

Resources

US, LA & SA: Planktonpopulations respond to naturalpopulation-regulatingconditions (biological factors,tidal flushing, inflow offreshwater carrying organicdetritus and dissolved organiccompounds, river discharge,water depth, tidal changes,turbidity, and dissolvedoxygen).

US: Plankton populations respond to naturaland human-induced perturbations to aquatichabitats.LA: Plankton populations in interior andupper portions of subprovinces are becomingmore saline-dominant species as land lossand saltwater intrusion into these interiorregions continues.SA: Species switching from fresh to salinetolerant plankton populations thatpredominate much of the area.

US: Plankton populationscontinue to respond to naturaland human-inducedperturbations to aquatic habitats.LA & SA: Continued land lossthroughout coastal Louisianaand the Study Area contributesto saltwater intrusion therebyfavoring saline-tolerant planktonpopulations.

US: Plankton populations continue to respond to natural andhuman-induced perturbations to aquatic habitats. Implementingthe NER would result in a comparatively small reduction to thepredominance of saline-tolerant populations.LA: Continued land loss throughout coastal Louisiana and theStudy Area contributes to saltwater intrusion, thereby favoringsaline-tolerant plankton populations. Implementing the NERwould result in a comparatively small reduction to thepredominance of saline-tolerant populations.A5 (NER): Restoration of 2,097 net acres would increase theamount of dissolved organic compounds and detritus exportedfrom the created and nourished barrier habitats thereby benefitinglocal plankton populations by increasing the planktonic foodsupply.A11: Impacts similar to NER except 363 net acres would creategreater benefits to plankton resources.A2: Impacts similar to alternative NER except 1,075 net acreswould create greater benefits to plankton resources.A3: Impacts similar to NER except 1,438 net acres would creategreater benefits to plankton resources.A4: Impacts similar to NER except 1,629 net acres would creategreater benefits to plankton resources.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Threatened &

Endangered

Species

US, LA & SA: Generaldecrease in populations andtheir critical habitats.Institutional recognition ofdecline in threatened andendangered species(Endangered Species Act) andtheir critical habitat.

US & LA: Continued institutionalrecognition of decline in threatened andendangered species and their critical habitatas National and State loss of species andtheir critical habitat continue. Total of about6,337 acres barrier habitat restored withbeneficial use of dredged material (746acres) and CWPPRA restoration projects(5,591 acres) contribute to various habitatsfor threatened and endangered species.SA: Continued loss of barrier habitat andcoastal wetlands resulting in loss of criticalhabitat (such as the gulf shoreline) for pipingplover and other threatened or endangeredspecies.

US: Continued institutionalrecognition of decline inthreatened and endangeredspecies and their critical habitatas National and State loss ofspecies and their critical habitatcontinue. Potential weakening ofEndangered Species Actespecially with regard to criticalhabitat.LA: Continued loss of barrierhabitat and coastal wetlandsresulting in loss of criticalhabitat (such as the gulfshoreline) for piping plover.SA: Continued loss of barrierhabitat and coastal wetlandsresulting in loss of criticalhabitat (such as the gulfshoreline) for piping plover andother threatened or endangeredspecies.

US & LA: Likely continue to institute individual speciesrecovery plans to maintain or increase populations and theircritical habitat. However, this would occur within a framework ofcontinued loss of critical habitat. Potential weakening ofEndangered Species Act especially with regard to critical habitat.Implementing the NER would result in a comparatively smallreduction, nationwide, to the loss critical habitat and threatenedand endangered species.A5 (NER): would not be likely to adversely impact brownpelican or piping plover or piping plover critical habitat; andwould not adversely impact any other threatened or endangeredspecies or their critical habitat. NER would restore 2,760 netacres of barrier habitats, including critical habitat for pipingplover.A11: similar to NER except a net total of 527 acresA2: similar to NER except a net total of 1,311 acresA3: similar to NER except a net total of 1,838 acresA4: similar to NER except a net total of 2,119 acres.

Historic &

Cultural

Resources

US, LA & SA: Historic &cultural resources subjected tonatural processes and man madeactions. Institutional recognitionvia National HistoricPreservation Act (and others).

US, LA & SA: Human activities as well asnatural processes can potentially degradeand/or destroy historic and cultural resources

US, LA & SA: Human activitiesas well as natural processes canpotentially degrade and/ordestroy historic and culturalresources

US & LA: Human activities as well as natural processes can

potentially degrade and/or destroy historic and cultural resources.A5 (NER): would work synergistically with other restorationprojects to provide critical and essential barrier islands, which, inturn, would provide some protection to cultural resources thatmay otherwise be damaged or lost due to coastal land loss.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Population US, LA & SA: Increasing populations in coastal areas.

US & LA: Large population centers andemployment and tourist activities.SA: Study area is remote, uninhabited, andinaccessible except by boat or aircraft.

US & LA: Increasing populationin urban and suburban areas,retreating population in ruralcoastal areas as land losscontinues.SA: Study area is remote anduninhabited.

US & LA: Increasing populations in urban and suburban areas,retreating population in rural coastal areas as land loss continues.A5(NER): Study area is remote and uninhabited.A11: Study area is remote and uninhabited.A2: Study area is remote and uninhabited.A3: Study area is remote and uninhabited.A4: Study area is remote and uninhabited.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Infrastructure

US, LA & SA: Increasinginfrastructure in the form ofroads, bridges, pipelines,homes, and businesses.

US: Heavy concentration of infrastructurethroughout coastal communities nationwide.LA: Heavy concentration of infrastructure inseveral parts of the State.SA: There is no public infrastructure on thebarrier islands. Private infrastructure consistsof oil and natural gas wells, transmissionlines, and petroleum distribution, storage,and processing facilities. All are at risk ofdamage and/or loss due to barrier island landloss storm impacts.

US: Heavy concentrations ofinfrastructure along coastal areasnationwide.LA: Increasing damage tocoastal infrastructure, reduceddevelopment of infrastructure inareas nearest to coast; relocationof some existing infrastructureassets.SA: The effects of continuedland loss and degradation wouldlead to increased costs formaintaining, protecting, andrepairing existing infrastructure.

US & LA: Heavy concentration of infrastructure along coastalareas nationwide. Increasing damage to coastal infrastructure,reduced development of infrastructure in areas nearest to coast;relocation of some infrastructure assets.A5 (NER): restoration of the islands, in combination with privateprotection measures, would provide some undetermined level ofprotection to infrastructure on and adjacent to the islands.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Commercial

Fisheries

US, LA & SA: Increases infisheries industry, due toadvancing technologies andincreased fishing pressure.

US, LA & SA: Regulation of fishingmaintains a billion dollar industry.LA: Total of about 6,337 acres barrier habitatrestored with beneficial use of dredgedmaterial (746 acres) and CWPPRArestoration projects (5,591 acres) contributeto various fishery habitats.

US: Some decline expected asvulnerability of habitatincreases. More regulationwould be necessary to maintaina sustainable industry.LA & SA: Severe decline ascoastal land loss continues.

US & LA: Decline in commercial fisheries expected asvulnerability of habitat increases.A5(NER): Net total of 2,097 acres of transitional estuarinemarine habitats used for spawning, nursery, nesting, and foragingby commercially and recreationally important species of finfishand shellfish, as well as other aquatic organisms. This would bein addition to restoration of similar habitats by other barrierhabitat restoration projects.A11: similar to NER except a net total of 363 acresA2: similar to NER except a net total of 1,075 acresA3: similar to NER except a net total of 1,438 acresA4: similar to NER except a net total of 1,629 acres.

Oyster Leases

US: Only major oyster leasingprogram is in Louisiana.LA & SA: General increase inacreage leased, productionlimited by saltwater intrusion inareas with no freshwaterintroduction.

US: Only major leasing program is inLouisiana.LA: Leveling off of acreage leased,production limited by saltwater intrusion inareas with no freshwater introduction.Production limited in areas by mortality fromover freshening by diversions.SA: 182,399 acres of oyster leasesthroughout Study Area.

US: Only major leasing programis in Louisiana.LA & SA: Gradual loss ofproduction from leases near gulfcoast due to increased salinities.Increased production in areasnearer freshwater introductions.

US & LA: Only major leasing program is in Louisiana.A5(NER): synergistic effect of implementing NER with a nettotal of 2,097 acres of intertidal estuarine habitat and additivecombination of impacts and benefits for overall net acres restoredby other Federal, State, local and private restoration efforts.A11: similar to NER except a net total of 363 acres.A2: similar to NER except a net total of 1,075 acres.A3: similar to NER except a net total of 1,438 acres.A4: similar to NER except a net total of 1,629 acres.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Oil, Gas, &

Mineral

US, LA & SA: Increasingdevelopment of refineries,wells, and other oil and gasproducing facilities andequipment.

US, LA & SA: Large investment inrefineries, wells, and other oil and gasproducing facilities and equipment.

US, LA & SA: Increaseddamages to refineries, wells, andother oil and gas producingfacilities and equipment;probable relocations of theseassets.

US & LA: Same as FWOP, except implementation of the NERwould reduce damages to oil and gas producing facilities andequipment; and reduced relocations of these assets (as comparedto the without-project condition).A5 (NER): implementation provides the cumulative impact of

protecting oil and natural gas wells, transmission lines, pumping,storage, and processing facilities located both on and behind thebarrier islands by providing restored, revegetated, and breachresistant uplands, thereby increasing protection from future stormsurges.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Navigation

US, LA & SA: Increasing portfacilities and inland waterwaysand traffic.

US, LA & SA: Large investment in portfacilities and inland waterways and traffic.

US & LA: Probable damages toand relocation of port facilitiesand inland waterways andtraffic.SA: potential for increasedfrequency and cost formaintenance of the HoumaNavigation Canal (a Federalchannel) and numerousprivately-maintained channels.

US & LA: Greater investment in port facilities and inlandwaterways (as compared to the without-project condition).Implementing the NER would have an undetermined, but

positive effect on navigation channels in the Terrebonne Basin byreducing the impact of storms and storm surges on the sedimentthat causes shoaling.A5 (NER): cumulative, but undetermined positive impact onHouma Navigation Canal and other private channel maintenancecosts and frequency.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Flood Control

US, LA & SA: Construction offlood control levees, pumpingstations, and control structures.

US, LA: Large investment in flood controllevees, pumping stations, and controlstructures.SA: There are no flood control structures orsystems in the SA.

US, LA: Increased investment inflood control levees, pumpstations, and other flood controlfacilities to prevent damage dueto land loss.SA: There are no flood controlstructures or systems in the SA.

US & LA: Reduced investment in flood control facilities (ascompared to without-project conditions).A5 (NER): While increasing the island acreage would not reducestorm surge or wave heights in the area, it would have the effectof lowering storm surge impacts on existing wetlands and landlinks in the Terrebonne Basin.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Pipelines

US, LA & SA: Development ofextensive network of oil and gaspipelines.

US, LA & SA: Large investment in extensivenetwork of oil and gas pipelines; increasingdamages to and some relocation of theseassets.

US, LA & SA: Increaseddamages and probablerelocations of pipeline assets dueto continued coastal land loss.

US & LA: Increased damages and probable relocations ofpipeline assets due to continued coastal land loss.A5 (NER): the cumulative impact of protecting both buried andexposed pipelines by providing an additional layer of soilprotection, thereby increasing protection against ongoing erosionand future storm surges.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Hurricane Risk

Reduction

Levees

US and LA: Construction ofhurricane risk reduction leveesand pumping capacity.SA: No hurricane risk reductionlevees within or nearby theStudy Area.

US, LA: Large investment in hurricane riskreduction levees and pumping capacity.SA: No hurricane risk reduction leveeswithin or nearby the Study Area.

US, LA: Increasing investmentin hurricane risk reductionfacilities to prevent damage dueto land loss.SA: No hurricane risk reductionlevees within or nearby theStudy Area.

US & LA: Increasing investment in hurricane risk reductionfacilities to prevent damage due to land loss. Implementing theNER would have no effect on hurricane risk reduction levees.A5 (NER): No hurricane risk reduction levees within or nearbyStudy Area.A11: same as NER.A2: same as NER.A3: same as NER.A4: same as NER.

Agriculture US, LA & SA: Not an issue.

US, LA & SA: Institutional recognition.LA: Saltwater intrusion, especially inChenier Plain problem for rice farmers.SA: There are no agriculture activities inStudy Area.

US: Continued institutionalrecognition.LA: Continued coastal land lossand saltwater intrusion reducesopportunities for agriculture.SA: No agriculture activities inStudy Area.

US: Continued institutional recognition. Implementing the NERwould not impact agriculture endeavors.LA: Continued coastal land loss and saltwater intrusion reducesopportunities for agriculture. Implementing the NER would notimpact agriculture endeavors.All Alternatives: No agriculture activities in Study Area.

Forestry US, LA & SA: Not an issue.

US: Institutional regulation of forest harvestpractices.LA: Institutional regulation of forest harvestpractices. Continued coast wide forestdeterioration, especially swamp and freshwetland forests.SA: There are no forestry or silvicultureactivities in Study Area.

US: Continued institutionalrecognition; however, increasinghuman populations result incontinued loss of forested areasand reduces forestryopportunities.LA: Continued land loss andsaltwater intrusion reducesforestry opportunities.SA: No forestry or silvicultureactivities in Study Area.

US & LA: Continued institutional recognition; increasing humanpopulation growth and continued demand for diminishingforestry resources and reduced forestry opportunities.Implementing the NER would have no impacts on forestry.All Alternatives: No forestry activities in Study Area.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Water Supply US, LA & SA: Not an issue.

US & LA: Significant investment in watersupply facilities (treatment plants, pipelines,etc.).SA: There are no water supply facilitieswithin the Study Area.

US & LA: Significantinvestment in water supplyfacilities (treatment plants,pipelines, etc.).SA: There are no water supplyfacilities within the Study Area

US & LA: Continued institutional recognition; continuedsaltwater intrusion; continued industrial pollution; continuedchanges to hydrology that affect water supply to wetlands.All Alternatives: No water supply facilities in Study Area.

Aesthetics

US, LA & SA: Generally not anissue until recent times.Institutional recognition viaWild and Scenic Rivers Act,Scenic Byways, and others.Technical recognition via 1988USACE Visual ResourcesAssessment Procedure.

US & LA: Human population growth,development, and other human activitieshave the potential to destroy, enhance, orpreserve visual resources.SA: The islands provide aestheticallypleasing views of beach, dune, and marshhabitats.

US, LA: Continued humanpopulation growth anddevelopment and other humanactivities have the potential todestroy, enhance, or preservevisual resources.SA: As the islands continue toerode and migrate north theywill eventually disappear (byTY50), thus the view willconvert to one of open water andscattered petroleum-relatedstructures.

US & LA: Continued human population growth and developmentand other human activities have the potential to destroy, enhance,or preserve the quality of scenic byways and other undeterminedvisual resources.A5(NER): The increase in beach, dune, and marsh environmentswould increase visual quality, increase the potential for long termstorm protection to coastal Louisiana, provide some habitatrestoration for wildlife and fisheries resources that also play avital role in the “living landscape,” and provide scale to criticalview sheds.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Recreation

Resources

US, LA & SA: Generally not anissue until recent times.

US: Nation-wide recreation resources areprovided primarily by the U.S. Departmentsof the Interior and Agriculture.LA & SA: Widespread coastal land losscauses dramatic changes in recreationopportunities.

US, LA & SA: Potential loss ofrecreational resource base due tocoastal land loss, including thebarrier islands and the interiorislands and marshes.

US & LA: Slowing or reversing land loss and coastal erosionmay protect recreation resources. Implementing the NER wouldimprove the recreational opportunities provided by the islands byincreasing their habitat areas and protecting them into the future.A5 (NER): the effects of implementing restoration with a netbenefit of 2,760 acres of beach, dune, and marsh over 50 yearswill be felt across the Terrebonne Basin, particularly in thecommunities that support the recreational fishing, hunting, andecotourism industries. The Terrebonne Basin is a worldrenowned destination for recreational anglers.A11: similar to NER except a net total of 527 acres.A2: similar to NER except a net total of 1,311 acres.A3: similar to NER except a net total of 1,838 acres.A4: similar to NER except a net total of 2,119 acres.

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SIGNIFICANT

RESOURCE

Past Actions

(Historic Conditions)

Present Action

(Existing Conditions)

Future Without-Project

The No Action Alternative

Cumulative Impacts

(Comparison of Future With Proposed Action Impacts

for each Restoration Alternative and the NER)

Noise

US, LA & SA: Generally not anissue until recent times.Institutional recognition - NoiseControl Act of 1972.

US, LA & SA: Nuisance noise generallyassociated with areas of human developmentand activities e.g., boats, airboats, and otherhuman activities may cause disturbances tofish and wildlife in remote regions of theStudy Area.

US, LA & SA: Continuedhuman population growth &development, recreationactivities, industry, and otherhuman activities typically havesome associated noise pollution.Further institutional recognitionlikely to be enacted.

US & LA: Continued human population growth & development,recreation activities, industry, and other human activitiestypically have some associated noise pollution. Furtherinstitutional recognition likely to be enacted.SA: Raccoon, Whiskey, and Wine Islands are State-managedwildlife refuges and public trespass is prohibited.A5 (NER): cumulative impacts are primarily related to potentialshort-term disruption, during construction activities, of wildlifespecies, most critically in bird rookeries and shorebird nestingareas. This will be addressed in cooperation with resourcemanagement agencies during project planning andimplementation.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

HTRW

US, LA & SA: Generally not anissue until recent times. Naturalsources of HTRW supplantedby human-induced HTRW.Institutional recognition (1976)RCRA, (1980) CERCLA,(1986) SARA, (1992) USACEvia ER 1165-2-132 Hazardous,Toxic, and Radioactive Waste(HTRW) Guidance.

US & LA: Continued human populationgrowth and development, industry, and otherhuman activities would typically have someHTRW associated with them. Furtherinstitutional recognition would likely beenacted.SA: Phase 1 investigation found no HTRWconcerns.

US, LA & SA: Continuedhuman population growth anddevelopment, industry, and otherhuman activities would typicallyhave some HTRW associatedwith them. Further institutionalrecognition would likely beenacted.

US & LA: Continued human population growth anddevelopment, industry, and other human activities typically havesome HTRW associated with them. Further institutionalrecognition likely to be enacted.A5 (NER): Consistent with ER 1165-2-132, an HTRWinvestigation was conducted for the Study Area. Based uponfindings from this investigation, the potential for cumulativeimpacts to the Study Area from implementation of the NERwould be low and would likely continue to be low into the future.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

Air Quality

US, LA & SA: Generally not anissue until recent times.Institutional recognition ofresource via Clean Air Act.General deterioration of airquality due to increases inhuman populations andindustry.

US, LA & SA: Continued institutionalrecognition. Continued deterioration of airquality due to increases in humanpopulations, industrial activities, andmotorized machinery/equipment/vehicleemissions.

US, LA & SA: Continueddeterioration of air quality due toincreases in human populations,industrial and motorizedmachinery/equipment/vehicleemissions.

US & LA: Continued deterioration of air quality due to increasesin human populations, industrial activities, and motorizedvehicle, equipment, and vessel emissions.A5(NER): Cumulative impacts would primarily be related to

direct air emissions during construction activities and would bereduced to background following construction completion. Thebackground would likely continue to be low into the future.A11: similar to NER.A2: similar to NER.A3: similar to NER.A4: similar to NER.

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This environmental analysis evaluates and compares, from a qualitative and

quantitative perspective, the No Action Alternative (Future Without Project

Conditions) to the four alternatives carried over for detailed analysis. Impact

analysis described in this chapter is based on a combination of scientific and

engineering analyses, professional judgment, and previously compiled information.

5.1 SOILS AND WATER BOTTOMS

5.1.1 Soils

5.1.1.1 No Action Alternative (Future without Project Conditions)

5.1.1.1.1 Direct

The No Action Alternative, not implementing the Terrebonne Basin Barrier

Shoreline Restoration project, would have no direct impacts on soil resources within

the seven island barrier system. Existing conditions, including continued barrier

island deterioration, fragmentation, degradation and the eventual loss of the barrier

islands and their associated environmental values and functions would persist..

5.1.1.1.2 Indirect

Without any action, approximately 3,220 acres of existing barrier soil resources

from the seven island Terrebonne Basin barrier system (East Timbalier, Timbalier,

Trinity, East Island, Wine, Whiskey and Raccoon Island) would likely continue to

deteriorate, degrade, fragment and eventually convert into shallow open water

bottoms. The Terrebonne Basin barrier island system would continue to experience

higher wave energy levels and associated shoreline erosion in the adjacent bays

(Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005). If the

Terrebonne Basin barrier island system is not restored, the adjacent estuarine bay

systems, along with their soil resources, will continue to be transformed into marine

open water habitat. The loss of soil resources would adversely impact important

transitional habitat between estuarine and marine environments; essential fish

habitat (EFH); unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting

habitats); and critical wintering habitat for the threatened piping plover. The

continued degradation and eventual loss of soil resources would result in the loss of

fish and wildlife habitat which would likely increase competition between and

within various fish and wildlife species for diminishing habitat resources. The loss

of vegetated wetlands would also result in a loss in primary productivity and

eventually result in conversion of the existing back bay estuarine system into more

marine open water system.

5.1.1.1.3 Cumulative

Louisiana has lost approximately 1,900 square miles of coastal wetland soil

resources since the 1930's (Dunbar et al. 1992; Barras et al. 1994; Barras et al.

2003). Approximately 10 percent of Louisianas remaining coastal wetlands would

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be lost at a rate of approximately 6,600 acres per year (over the next 50 years,

resulting in an additional net loss of 328,000 acres by 2050 (Barras et al. 2003). Land loss

in the Study Area would likely continue at rates similar to present resulting in the

projected loss over all seven of the Terrebonne barrier islands of about 3,220 acres

of barrier island soils, primarily Clovelly muck, Scatlake muck, Scatlake-Felicity

complex soils, by 2062. This projected loss of barrier island soil resources would be

in addition to the projected loss of soil resources throughout coastal Louisiana. The

LCA Study (USACE, 2004) estimated coastal Louisiana would continue to lose land

at a rate of approximately 6,600 acres per year over the next 50 years.

However, these soil losses would be offset to some extent by other Federal, State,

local, and private restoration efforts across coastal Louisiana (Table 5-2). In

addition, more recent restoration efforts would also cumulatively interact to help

offset losses of soil resources in the Study Area, including the following:

Table 5-2. Net Acres Created, Restored, and/or Protected by Other Federal,

State, Local, and Private Restoration Efforts (USACE, 2004)

Subprovince

1

(acres)

Subprovince

2

(acres)

Subprovince

3

(acres)

Subprovince

4

(acres)

Totals

(acres)

Breaux Act

CWPPRA 33,690 44,913 25,057 30,486 134,146

State 2,543 9,043 5,200 1,972 18,758

PCWRP 14 41 371 31 457

Mitigation

Civil Works

Projects

4,990 0 5,000 0 9,990

Mitigation

Regulatory

Permits1

6,411 3,199 2,635 2,983 15,228

Vegetation 535 878 1,785 1,931 5,129

Section

204/1135,

Beneficial Use

226 414 1,293 3,525 5,458

WRDA 16,000 33,000 0 0 49,000

Other 0 2,000 50,000 3,226 426,132

TOTALS 64,410 93,490 91,344 44,158 664,298

5.1.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.1.1.2.1 Direct

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Compared to the No Action Alternative, implementing Alternative 5 (NER Plan)

would initially restore a total of 5,840 acres of barrier soil resources including the

creation of 3,283 acres in addition to restoration of 2,557 acres of existing barrier

soil resources. This alternative would restore Raccoon, Timbalier, Trinity, and

Whiskey Islands to their minimal geormorphological form along with 5-years of

advanced fill for Trinity and Whiskey Islands and 25-years advanced fill for

Raccoon and Timbalier Islands. Following is an island-by-island breakdown of the

acres of soil resources created for each of the island components of the NER Plan

including the renourishment events.

Alternative 5 (NER Plan) would initially restore a total of 789 acres of barrier soil

resources on Raccoon Island, including restoration of 235 acres of existing

degrading barrier soil resources and creation of an additional 554 acres of barrier

soil resources. Additional direct impacts would include renourishment at target

year 30 (TY30) of 658 acres of beach and dune soil resources along Raccoon Island.

Alternative 5 (NER Plan) would initially restore a total of 1,272 acres of barrier soil

resources on Whiskey Island including restoration of 820 acres of existing degrading

barrier soil resources and creation of an additional 469 acres of barrier soil

resources. Additional direct impacts would include renourishment of 929 acres and

905 acres of beach and dune soil resources at TY20 and TY 40, respectively.

Alternative 5 (NER Plan) would initially restore a total of 1,149 acres of barrier soil

resources on Trinity Island including restoration of 582 acres of existing degrading

barrier soil resources and creation of an additional 585 acres of barrier soil

resources. Additional direct impacts would include renourishment of 1,151 acres of

beach and dune soil resources at TY25.

Alternative 5 (NER Plan) would initially restore a total of 2,630 acres of barrier soil

resources on Timbalier Island including restoration of 979 acres of existing

degrading barrier soil resources and creation of an additional 1,675 acres of soil

resources. Additional direct impacts would include renourishment of 1,786 acres of

beach and dune soil resources at TY 30.

Placement of borrow material would unavoidably bury existing barrier shoreline,

dune, marsh, and shallow water bottom soil resources. Following placement,

consolidation of borrow material would take about one year. Adverse direct impacts

of placing a total of 20,246,338 cy of borrow material into the dynamic high energy

Terrebonne Basin barrier system would generally be minimized by placement of

like-on-like sediments in this sediment-starved barrier system.

5.1.1.2.2 Indirect

Compared to the No-Action Alternative, indirect impacts of implementing

Alternative 5 (NER Plan) would be restoration of a net total of 2,781 acres of barrier

island soil resources including 641 net acres on Raccoon, 527 net acres on Whiskey,

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289 net acres on Trinity, and 1,324 net acres on Timbalier Islands. Borrow

sediments used for barrier restoration would be subjected to biogeochemical

processes that would, over time, begin to more closely resemble the Scatlake and

Felicity soils that they would be covering. Hence, additional indirect impacts would

include the ecological and geomorphologic benefits associated with the deposition

and natural redistribution of a total of 67,184,714 cy, including 46,264,549 cy of

initial fill and 20,920,165 cy of renourishment of sand and marsh-compatible soils

throughout the Terrebonne Basin barrier island system over the 50-year period of

analysis.

Restoration of barrier shoreline, dune, back-barrier marsh, and shallow open water

soil resources would also indirectly affect plant and animal establishment and

growth, invertebrate colonization, and other factors (Callaway 2001). Although

there would be some short-term adverse impacts associated with placement of

borrow material (e.g., compaction of existing soil horizons) the long-term impacts

would generally be positive by providing soil resources suitable for recolonization by

plants and animals. Restoration of beach, dune and back barrier marsh soil

resources would provide suitable substrate for establishing barrier vegetation

resources, which, would increase important transitional fish and wildlife habitat

between marine and estuarine environments, provide important barrier shoreline

haul-out habitat for threatened and endangered sea turtle, and increase critical

wintering habitat for the threatened piping plover thereby facilitating the nationwide recovery of this threatened species.

5.1.1.2.3 Cumulative

Cumulative impacts would be the incremental impact from implementing

Alternative 5 (NER Plan) when added to all past, present and reasonably

foreseeable similar barrier restoration efforts. Alternative 5 (NER Plan) would

restore a net total of 2,781 acres of barrier soil resources on Raccoon (net total 641

acres), Whiskey (net total 527 acres), Trinity (net total 289 acres), and Timbalier

Islands (net total 1,324 acres) which would be in addition to impacts and benefits

for overall net acres of barrier soil resources created, nourished, restored, and/or

protected by other Federal, State, local, and private restoration efforts. Coastal

barrier land loss in Louisiana has been addressed, to some degree, by efforts under

the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA)

program, and the beneficial use of dredged material requirements under Section

307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.1.1.3 Alternative 11: Whiskey (Plan C with renourishment)

5.1.1.3.1 Direct

Compared to the No Action Alternative, implementing Alternative 11 would be

similar to those described for the Whiskey Island component of Alternative 5 (NER

Plan), including initial restoration of a total 1,272 acres of barrier soil resources on

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Whiskey Island, restoration of 820 acres of existing degrading barrier soil resources

and creation of an additional 469 acres of barrier soil resources. Additional direct

impacts would include renourishment of 929 acres and 905 acres of beach and dune

soil resources at TY20 and TY 40, respectively.

5.1.1.3.2 Indirect

Compared to the No-Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan), including restoration of a net total 527

acres over the 50-year period of analysis. Borrow sediments used for restoration of

Whiskey Island would be subjected to biogeochemical processes that would, over

time, begin to more closely resemble the Scatlake and Felicity soils that they would

be covering. Hence, additional indirect impacts would include the ecological and

geomorphologic benefits associated with the deposition and natural redistribution of

a total of 16,660,430 cy, including 8,909,939 cy of initial fill and 8,330,215 cy of

renourishment of sand and marsh-compatible soils throughout the Terrebonne

Basin barrier island system over the 50-year period of analysis.

5.1.1.3.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres of barrier soil resources

on Whiskey Island with the additive combination of impacts and benefits for overall

net acres of barrier soil resources created, nourished, restored, and/or protected by

other Federal, State, local, and private restoration efforts. Coastal barrier land loss

in Louisiana has been addressed, to some degree, by efforts under the Coastal

Wetlands Planning, Protection and Restoration Act (CWPPRA) program, and the

beneficial use of dredged material requirements under Section 307 of the Coastal

Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.1.1.4 Alternative 2: Timbalier (Plan E)

5.1.1.4.1 Direct

Compared to the No Action Alternative, implementing Alternative 2 would be

similar to those described for the Timbalier Island component of Alternative 5 (NER

Plan), including initial restoration of a total 2,630 acres of barrier soil resources on

Timbablier Island, restoration of 979 acres of existing degrading barrier soil

resources and creation of an additional 1,675 acres of barrier soil resources.

Additional direct impacts would include renourishment of 1,151 acres of beach and

dune soil resources at TY25.

5.1.1.4.2 Indirect

Compared to the No-Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

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component of Alternative 5 (NER Plan) including restoration of a net total 1,324

acres over the 50-year period of analysis. Borrow sediments used for restoration of

Whiskey Island would be subjected to biogeochemical processes that would, over

time, begin to more closely resemble the Scatlake and Felicity soils that they would

be covering. Hence, additional indirect impacts would include the ecological and

geomorphologic benefits associated with the deposition and natural redistribution of

a total of 20,246,338 cy, including 19,776,135 cy of initial fill and 470,203 cy of

renourishment of sand and marsh-compatible soils throughout the Terrebonne

Basin barrier island system over the 50-year period of analysis.

5.1.1.4.3 Cumulative

Cumulative impacts would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including restoring a net total of 1,324 acres

of barrier soil resources on Timbalier Island with the additive combination of

impacts and benefits for overall net acres of barrier soil resources created,

nourished, restored, and/or protected by other Federal, State, local, and private

barrier island restoration efforts. Coastal barrier land loss in Louisiana has been

addressed, to some degree, by efforts under the Coastal Wetlands Planning,

Protection and Restoration Act (CWPPRA) program, and the beneficial use of

dredged material requirements under Section 307 of the Coastal Zone Management

Act of 1972, 16 U.S.C. 1451 et. seq.

5.1.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.1.1.5.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

3 would be similar to the direct impacts described above for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan).

The Whiskey Island restoration component of Alternative 3 would initially restore a

total 1,272 acres of barrier soil resources, including restoration of 820 acres of

existing degrading barrier soil resources and creation of an additional 469 acres of

barrier soil resources. Additional direct impacts of the Whiskey Island component

of Alternative 3 would include renourishment of 929 acres and 905 acres of beach

and dune soil resources at TY20 and TY 40, respectively.

The Timbalier Island component of Alternative 3 would initially restore a total

2,630 acres of barrier soil resources, including restoration of 979 acres of existing

degrading barrier soil resources and creation of an additional 1,675 acres of barrier

soil resources. Additional direct impacts of the Timbalier Island component of

Alternative 3 would include renourishment of 1,151 acres of beach and dune soil

resources at TY25.

5.1.1.5.2 Indirect

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Compared to the No-Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described above for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan).

Indirect impacts would include restoration of a net total 1,851 acres (527 net acres

on Whiskey Island and 1,324 net acres on Timbalier Island) over the 50-year period

of analysis. Borrow sediments used for restoration of Whiskey and Timbalier

Islands would be subjected to biogeochemical processes that would, over time, begin

to more closely resemble the Scatlake and Felicity soils that they would be covering.

Hence, additional indirect impacts would include the ecological and geomorphologic

benefits associated with the deposition and natural redistribution of a total of

43,846,142 cy, including 28,686,074 cy of initial fill and 15,160,068 cy of

renourishment of sand and marsh-compatible soils throughout the Terrebonne

Basin barrier island system over the 50-year period of analysis.

5.1.1.5.3 Cumulative

Cumulative impacts of implementing Alternative 3 would be similar to those

described for the Whiskey and Timbalier Island components of Alternative 5 (NER

Plan). The synergistic interaction of implementing both the Timbalier and Whiskey

Island restoration components of Alternative 3 would result in a net total of 1,851

acres (Whiskey Island 527 net acres and Timbalier Island 1,324 acres) restored over

the 50 year period of analysis along with the additive combination of impacts and

benefits for net acres of barrier islands restored by other Federal, State, local, and

private restoration efforts.

5.1.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.1.1.6.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

4 would be similar to those described for the Whiskey, Trinity and Timbalier Island

components of Alternative 5 (NER Plan).

The Whiskey Island component would initially restore a total of 1,272 acres of

barrier soil resources including restoration of 820 acres of existing degrading

barrier soil resources and creation of an additional 469 acres of barrier soil

resources. Additional direct impacts would include renourishment of 929 acres and

905 acres of beach and dune soil resources at TY20 and TY 40, respectively.

The Trinity Island component would initially restore a total of 1,149 acres of barrier

soil resources including restoration of 582 acres of existing degrading barrier soil

resources and creation of an additional 585 acres of barrier soil resources.

Additional direct impacts would include renourishment of 1,151 acres of beach and

dune soil resources at TY25.

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The Timbalier Island component would initially restore a total of 2,630 acres of

barrier soil resources including restoration of 979 acres of existing degrading

barrier soil resources and creation of an additional 1,675 acres of soil resources.

Additional direct impacts would include renourishment of 1,786 acres of beach and

dune soil resources at TY 30.

5.1.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Island components of Alternative 5 (NER Plan). This would include a net

total of 2,140 acres of barrier island soil resources including 527 net acres on

Whiskey, 289 net acres on Trinity, and 1,324 net acres on Timbalier Islands.

Borrow sediments used for barrier restoration would be subjected to biogeochemical

processes that would, over time, begin to more closely resemble the Scatlake and

Felicity soils that they would be covering. Hence, additional indirect impacts would

include the ecological and geomorphologic benefits associated with the deposition

and natural redistribution of a total of 55,246,837 cy (cy), including 36,272,884 cy of

initial fill and 18,973,953 cy of renourishment of sand and marsh-compatible soils

throughout the Terrebonne Basin barrier island system over the 50-year period of

analysis.

5.1.1.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey, Trinity,

and Timbalier Island components of Alternative 5 (NER Plan). This would include

the synergistic interaction of restoring a net total of 2,140 acres of barrier soil

resources on Whiskey (net total 527 acres), Trinity (net total 289 acres), and

Timbalier Islands (net total 1,324 acres) with the additive combination of impacts

and benefits for overall net acres of barrier soil resources created, nourished,

restored, and/or protected by other Federal, State, local, and private restoration

efforts. Coastal barrier land loss in Louisiana has been addressed, to some degree,

by efforts under the Coastal Wetlands Planning, Protection and Restoration Act

(CWPPRA) program, and the beneficial use of dredged material requirements under

Section 307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.1.2 Water bottoms

5.1.2.1 No Action Alternative (Future without Project Conditions)

5.1.2.1.1 Direct

The No Action Alternative, not implementing the Terrebonne Basin Barrier

Shoreline restoration, would have no direct impacts on existing water bottoms.

5.1.2.1.2 Indirect

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The No Action Alternative would result in the conversion of approximately 3,220

acres of existing Terrebonne Basin barrier island beach, dune and marsh habitats

to water bottoms. Conversion of existing barrier island beach, dune and marsh

habitat to water bottom habitat would include degradation and loss of important

and essential fish and wildlife habitats used for shelter, nesting, feeding, roosting,

cover, nursery, and other life requirements; reduction in productivity; degradation

and loss of EFH, especially transitional habitat between estuarine and marine

environments; degradation and loss of stopover habitat for migrating neotropic

birds; and increased inter- and intra-specific competition between resident and

migratory fish and wildlife species for decreasing coastal barrier island resources.

5.1.2.1.3 Cumulative

Cumulative impacts to water bottoms would be the synergistic effect of the NoAction Alternative of converting 3,220 acres of existing Terrebonne Basin barrier

island habitats to water bottoms, along with the additive combination of

approximately 10% of Louisianas remaining coastal wetlands being converted to

water bottoms at a rate of 6,600 acres per year over the next 50 years, resulting in

an additional net loss of 328,000 acres by 2050 (Barras et al. 2003). These impacts

would be offset, to some degree, by the additive combination of impacts and benefits

for overall acres of water bottoms impacted by other Federal, State, local, and

private restoration efforts. Coastal water bottoms in Louisiana have been impacted,

to some degree, by efforts under the CWPPRA program, and the beneficial use of

dredged material requirements under Section 307 of the Coastal Zone Management

Act of 1972, 16 U.S.C. 1451 et. seq.

5.1.2.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.1.2.2.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative 5 (NER

Plan) would include impacts to water bottoms within the offshore borrow areas as well as

impacts to water bottoms within the barrier island restoration and creation areas. Initial

construction would remove a total of 55,787,481 cy of borrow material from a total

of 2498 acres of water bottoms in the offshore borrow areas including 1187 acres at

Ship Shoal; 744 acres at the South Pelto; 83 acres at Raccoon Island; 87 acres at

New Cut; and 397 acres at Whiskey 3A. Renourishment would remove a total of

23,639,786 cy from a total of 1222 acres of water bottoms in offshore borrow areas

including 26 acres at South Pelto and 1196 acres at Ship Shoal.

Initial construction would cover a total of 3,283 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 71 acres at TY30

on Raccoon Island, 474 acres at TY 20 and 349 acres at TY40 on Whiskey Island;

537 acres on Trinity Island at TY 25; and 202 acres on Timbalier Island at TY30.

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A total of 3,283 acres of existing water bottoms would be converted to beach, dune

and marsh barrier habitats by placement of a total of 55,787,481 cy of borrow

material during initial construction. Dredging and placement of borrow material

could destroy any slow-moving or sessile benthic organisms found within the borrow

areas and within the barrier island restoration/creation areas.

Construction of the terminal groin on Raccoon Island would directly impact a total

of 2 acres of Gulf of Mexico water bottoms.

Nairn et al. (2004) conducted an extensive literature review and developed a

monitoring program for MMS to evaluate long-term impacts of sand dredging

operations on the outer continental shelf (OCS), including Ship Shoal. Primary

impacts of concern include changes to the sea bed resulting in changes to the

erosion and sedimentation processes along the shore and changes to the sea bed

that would have direct and significant impacts on the biological environment

including: removal and alteration of substrate; loss of essential fish habitat (EFH);

dredging could remove existing benthic community systems in the areas where

sands are removed (previous studies have shown recovery within three years);

turbidity plumes associated with dredging would elevate levels of suspended

inorganic and organic solids; reduction in elevation of the seabed and exposure of

the underlying sediment layer with different characteristics such as grain size,

reduced dissolved oxygen levels and compaction (Nairn et al. 2004).

Despite completing a cultural survey of the borrow areas, there remains a potential

for cultural or historic relics to be disturbed or lost during dredging operation.

Despite extensive surveys of the borrow sites, there remains a potential for

disturbing oil and gas infrastructure (pipelines, platforms, and other structures).

There would also be a potential for incidental takings of sea turtles during dredging

operations, despite all possible precautions being taken (e.g., use of turtle exclusion

devices, observers, etc.) to avoid, minimize and reduce any such impacts. Sediment

plumes created by dredge operations would be small and temporary; consequently,

effects to plankton, fish and marine mammals should be minimal and of short

duration (Nairn et al 2004; Hardaway et al 1998; Hammer et al 1993).

5.1.2.2.2 Indirect

Indirect impacts to water bottoms of implementing Alternative 5 (NER Plan) would

include the natural redistribution, via natural coastal longshore transport

processes, of a portion of the total 67,184,714 cy of borrow sediments throughout the

Terrebonne barrier island system over the 50-year period of analysis.

The 1,200-ft long terminal groin at Raccoon Island would intersept the net

longshore sediment flux, thereby retaining sediment on the beach up-drift of the

groin. The terminal groin would reduce longshore erosion by capturing sediments

that would otherwise be lost through offshore transport and deposition. The

longshore sediment transport moves material off of Raccoon Island to the west and

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is lost to the shoals and perhaps buried by the mud stream from the Atchafalaya

River.

A total of 67,184,714 cy of sediments would be dredged from borrow site water

bottoms for use in barrier island restoration. This action could potentially alter

wave dynamics, thereby changing onshore storm-wave impacts, possibly leading to

greater shoreline erosion. However, Stone et al. (2004) indicates that removal of

Ship Shoal sands for barrier/coastal restoration efforts would not significantly

influence wave conditions in the nearshore because the expected increase in wave

energy is limited to the leeward flank of the shoal. For near-shore borrow areas, the

borrow pit would be designed to minimize the potential to alter wave dynamics

(including sufficient distance from the existing shoreline).

Other indirect impacts would include: marine organisms that presently utilize the

gulf bottom substrates (especially benthos) would have to adapt to changes in gulf

bottom topography; restoration construction activities could cause short-term

disruption of commercial and recreational fishing; and alteration of gulf water

bottoms may change littoral drift dynamics; creation of depressions, furrows, and

pits could impact recolonization by the benthic community (Nairn et al 2004). The

primary concern is the potential for ridge and shoal type features to deflate or be

smoothed out where borrow deposits are accessed on an ongoing basis. This could

lead to large-scale impacts to biological communities (Nairn et al. 2004). However,

Stone et al. (2004) indicates that removal of Ship Shoal sands for barrier/coastal

restoration efforts would not significantly influence wave conditions in the

nearshore because the expected increase in wave energy is limited to the leeward

flank of the shoal. In addition, the MMS, International Activities and Marine

Minerals Division is charged with management of Federal Outer Continental Shelf

(OCS) sand and gravel resources that would be used for beach nourishment to

repair storm damage and protect against sea-level rise. To reduce potential

environmental damage associated with long-term and large-scale use of these

resources, a project was funded by MMS to design a comprehensive physical and

biological monitoring program for sand-mining activities.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.1.2.2.3 Cumulative

Cumulative impacts to water bottoms would be the synergistic effect of

implementing Alternative 5 (NER Plan), with impacts to a total of 7,003 acres of

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water bottoms, along with the additive combination of impacts and benefits of

existing wetlands being converted to water bottoms at a rate of 6,600 acres per year

over the next 50 years, resulting in an additional net loss of 328,000 acres by 2050

(Barras et al. 2003). As discussed in Chapter 4, barrier resources are utilized by a

broad range of fish, wildlife, benthic and humans, thereby benefiting more than just

the State of Louisiana. Implementing Alternative 5 (NER Plan) would restore

degrading barrier habitats to higher quality barrier habitats, which would likely

result in a net increase in important benthic and other barrier resources. The

incremental cumulative impacts of implementing Alternative 5 (NER Plan) would

be in synergistic combination to impacts and benefits for overall net acres of barrier

resources created, nourished, restored, and/or protected by other Federal, State,

local, and private restoration efforts. Coastal barrier island conversion to water

bottoms in Louisiana has been addressed, to some degree, by efforts under the

CWPPRA program, and the beneficial use of dredged material requirements under

Section 307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.1.2.3 Alternative 11: Whiskey (Plan C with renourishment)

5.1.2.3.1 Direct

Compared to the No Action Alternative, direct impacts to water bottoms of

implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 10,340,701 cy of sediments from a total of 535 acres of borrow site water

bottoms including: 487 acres at Ship Shoal, and 48 acres at Whiskey Area 3a.

Renourishment would remove a total of 16,599,548 cy of borrow material from a

total of 859 acres at Ship Shoal; with 9,413,143 cy removed from 487 acres at TY20

and 7,186,405 cy from 372 acres at TY40.

Initial construction would cover approximately 469 acres of water bottoms and

fragmented barrier habitats. Renourishment with borrow material from Ship Shoal

would directly impact a total of 474 acres and 349 acres of water bottoms and

fragmented barrier habitats at TY20 and TY40, respectively.

5.1.2.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the natural redistribution of a

portion of the total 26,940,249 cy of sediments throughout the Terrebonne Basin

barrier island system over the 50-year period of analysis. Additional indirect

impacts would be the prevention of a net total of 527 acres of barrier habitats

converting to water bottoms over the 50-year period of analysis.

5.1.2.3.3 Cumulative

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Cumulative impacts of implementing Alternative 11 would be similar to those

described for the Whiskey Island component of Alternative 5 (NER Plan) including

dredging a total of 26,940,249 cy of sediments from 1,394 acres of existing borrow

site water bottoms. These impacts would be offset, to some extent, by the prevention

of a net total of 527 acres of barrier habitats converting to water bottoms over the

50-year period of analysis. In addition, implementing Alternative 11 would restore

degrading barrier habitats to higher quality barrier habitats, which would likely

result in a net increase in important benthic and other barrier resources. These

incremental cumulative impacts of implementing Alternative 11 would be in

addition to impacts and benefits for acres of barrier islands created, nourished,

restored, and/or protected by other Federal, State, local, and private restoration

efforts.

5.1.2.4 Alternative 2: Timbalier (Plan E)

5.1.2.4.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

2 would be similar to those described for the Timbalier Island component of

Alternative 5 (NER Plan). Initial construction would remove a total of 25,214,803 cy

of sediments from a total of 1,375 acres of borrow site water bottoms including: 613

acres at South Pelto and 396 acres at Whiskey 3a (beach and marsh).

Renourshiment at TY30 would remove a total of 531,329 cy of borrow material from,

26 acres at South Pelto borrow site.

Initial construction would cover approximately 1,675 acres of existing water

bottoms and fragmented barrier habitats. Renourishment at TY30, with borrow

material from South Pelto, would directly impact a total of 202 acres of water

bottoms and fragmented barrier habitats.

5.1.2.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including the natural redistribution of a

portion of the 20,246,338 cy of sediments throughout the Terrebonne Basin barrier

island system over the 50-year period of analysis. Additional indirect impacts

would be the prevention of a net total of 1,324 acres of barrier habitats converting to

water bottoms over the 50-year period of analysis.

5.1.2.4.3 Cumulative

Cumulative impacts of implementing Alternative 2 would be similar to those

described for the Timbalier Island component of Alternative 5 (NER Plan) including

dredging a total of 25,746,132 cy of sediments from a total of 1,375 acres of borrow

site water bottoms. These impacts would be offset, to some extent, by the prevention

of a net total of 1,324 acres of barrier habitats converting to water bottoms over the

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50-year period of analysis. In addition, implementing Alternative 2 would restore

degrading barrier habitats to higher quality barrier habitats, which would likely

result in a net increase in important benthic and other barrier resources. These

incremental cumulative impacts of implementing Alternative 2 would be in addition

to impacts and benefits for acres of barrier islands created, nourished, restored,

and/or protected by other Federal, State, local, and private restoration efforts.

5.1.2.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.1.2.5.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

3 would be similar to those described for the Whiskey and Timbalier Islands

components of Alternative 5 (NER Plan). Initial construction would remove a total

of 35,381,587 cy of borrow material from a total of 1,535 acres of water bottoms in

the offshore borrow areas including 487 acres at Ship Shoal; 613 acres at the South

Pelto; 39 acres at Raccoon Island; and 396 acres at Whiskey Area. Renourishment

would remove a total of 17,130,877 cy from a total of 885 acres of water bottoms in

offshore borrow areas including 27 acres at South Pelto and 859 acres at Ship

Shoal.

Initial construction would cover a total of 2,144 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 474 acres at TY

20 and 349 acres at TY30 on Whiskey Island and 202 acres on Timbalier Island at

TY40.

5.1.2.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing Alternative 3 would

be similar to those described for the Whiskey and Timbalier Island components of Alternative 5

(NER Plan) including the natural redistribution of a portion of the 47,186,587 cy of borrow

sediments throughout the Terrebonne Basin barrier island system over the 50-yer period of

analysis. Additional indirect impacts would be the prevention of a net total of 1,851 acres of

barrier habitats converting to water bottoms over the 50-year period of analysis.

5.1.2.5.3 Cumulative

Cumulative impacts of implementing Alternative 3 would be similar to those

described for the Whiskey and Timbalier Islands components of Alternative 5 (NER

Plan) with the following exceptions: the synergistic interaction of the effects of

implementing the LCA TBBSR Study would directly impact approximately 1,535

acres in the offshore borrow areas and 4,779 acres of water bottoms in the Study

Area. In addition, implementing Alternative 3 would restore degrading barrier

habitats to higher quality barrier habitats, which would likely result in a net

increase in important benthic and other barrier resources. These incremental

impacts of implementing Alternative 3 would be in addition to impacts and benefits

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for acres of barrier islands created, nourished, restored, and/or protected by other

Federal, State, local, and private restoration efforts.

5.1.2.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.1.2.6.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

4 would be similar to those described for the Whiskey, Trinity and Timbalier

Islands components of Alternative 5 (NER Plan). Initial construction would remove

a total of 44,544,496 cy of borrow material from a total of 1,998 acres of water

bottoms in the offshore borrow areas including 803 acres at Ship Shoal; 613 acres at

the South Pelto; 39 acres at Raccoon Island; 147 acres at New Cut; and 396 acres at

Whiskey Area. Renourishment would remove a total of 21,440,567 cy from a total of

1,108 acres of water bottoms in offshore borrow areas including 26 acres at South

Pelto and 1,082 acres at Ship Shoal.

Initial construction would cover a total of 2,729 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 474 acres at TY

20 and 349 acres at TY40 on Whiskey Island; 537 acres on Trinity Island at TY 25;

and 202 acres on Timbalier Island at TY30 Island at TY30

5.1.2.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Island components of Alternative 5 (NER Plan) including the natural

redistribution of a portion of the 55,246,837 cy of borrow sediments throughout the

Terrebonne Basin barrier island system over the 50-year period of analysis.

Additional indirect impacts would be the prevention of a net total of 2140 acres of

barrier habitats converting to water bottoms over the 50-year period of analysis.

5.1.2.6.3 Cumulative

Cumulative impacts of implementing Alternative 4 would be similar to those

described for Alternative 5 (NER Plan) with the following exceptions: the

synergistic interaction of the effects of implementing the LCA TBBSR Study would

directly impact approximately 3,106 acres in the offshore borrow areas and 153

acres of water bottoms in the Study Area. In addition, implementing Alternative 4

would restore degrading barrier habitats to higher quality barrier habitats, which

would likely result in a net increase in important benthic and other barrier

resources. These incremental cumulative impacts of implementing Alternative 4

would be in addition to impacts and benefits for acres of barrier islands created,

nourished, restored, and/or protected by other Federal, State, local, and private

restoration efforts.

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5.2 COASTAL PROCESSES AND HYDROLOGY

5.2.1 Flow and Water Levels

5.2.1.1 No action Alternative (Future without Project Conditions)

5.2.1.1.1 Direct

Not implementing proposed restoration of the Terrebonne Basin barrier shoreline

would have no direct impacts on coastal processes, flows or water levels.

5.2.1.1.2 Indirect

The primary indirect impacts of not implementing the proposed Terrebonne Basin

barrier shoreline restoration measures would be associated with changes in coastal

processes. Both natural and human-induced changes to coastal processes of water

flows and levels would continue. The natural and human-induced hydrological

modifications to coastal processes that have influenced flows and water levels

throughout the Louisiana coastal barrier systems is well documented (USACE,

2004). Natural subsidence, barrier shoreline erosion due to waves and storms,

construction of oil and gas exploration canals, construction and maintenance

(dredge and fill activities) of navigation channels, as well as mineral extraction

would continue to contribute to alteration of the natural coastal processes and flow

and water levels within the Terrebonne barrier system. These and other influences

have resulted and will continue to result in the Terrebonne barrier islands moving,

changing shape and decreasing in size over time (Williams et al. 1992).

Construction of navigation channels, as well as natural coalescence of tidal passes,

will continue to influence coastal processes and the Terrebonne barrier systems.

The Terrebonne barrier system has been displaced by the coalescence of tidal passes

(Gosselink and Sasser, 1995). Three main passes that were present in the

Terrebonne barrier system in 1891 had coalesced into Cat Island Pass by 1974, part

of which is now occupied by the former locations of Callou and Wine Islands (Suter

and Penland 1987). This pass, partly dredged and partly natural, continues to

dominate estuarine hydraulics within the barrier system despite the opening of

numerous shallow storm channels through the deteriorating islands.

Increased channelization, including construction of navigation and oil and gas

exploration canals, especially evident on Timbalier and East Timbalier Islands,

have altered water flows and contributed to disruption of the longshore transport as

well as changing the barrier island rollback dynamics (Penland and Boyd 1985;

Penland et al. 1988). These impacts would continue into the future thereby further

contributing to Terrebonne barrier island land loss. The continued loss of the

Terrebonne barrier system could indirectly impact the adjacent Terrebonne Basin

estuarine system. Stone (2005) found that barrier islands serve to absorb wave

energy during storms and fair-weather conditions, thereby provide some storm

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surge protection for the interior marshes within the basin, which would decrease

land loss erosion rates substantially.

The continued loss of the Terrebonne barrier islands would also work

synergistically, to some unknown extent, with increased channelization in nearby

mainland estuarine marshes with previously low drainage densities which could

allow: 1) the more efficient penetration of salt water into areas previously isolated

from direct exchanges, and 2) increase in tidal flows which are thought by some to

enhance erosion of some marsh types (Stevenson et al. 1985; Gagliano et al. 1981).

Indirect effects of channelization could also include a further loss of mainland

wetlands by erosion of canal banks subsequent to dredging (Gosselink and Sasser,

1995).

5.2.1.1.3 Cumulative

Natural and human-induced changes to coastal processes throughout coastal

Louisiana has resulted in the loss of approximately 1,900 square miles of coastal

wetland resources since the 1930's (Dunbar et al. 1992; Barras et al. 1994; Barras et

al. 2003). Natural and human-induced changes to coastal processes, if left

unchecked, would result in the loss of approximately 10 percent of Louisianas

remaining coastal wetlands at a rate of approximately 6,600 acres per year over the

next 50 years. This would result in an additional net loss of 328,000 acres by 2050

(Barras et al. 2003). If the natural and human-induced changes to coastal process

responsible for continued land loss continue in the Study Area, the Terrebonne

Basin barrier island system would likely continue to be lost at rates similar to

present resulting in the projected loss over all seven of the Terrebonne barrier

islands of about 3,220 acres by 2062. This projected loss of barrier island soil

resources would be in addition to the projected loss of barrier resources throughout

coastal Louisiana.

The LCA Study (USACE, 2004) estimated coastal Louisiana would continue to lose

land at a rate of approximately 6,600 acres per year over the next 50 years.

Cumulative impacts would be the synergistic effect of the No-Action Alternative on

coastal processes of flows and water levels with the additive combination of similar

barrier system degradation and barrier island loss impacts to flow and water levels

throughout coastal Louisiana, as well as the benefits and impacts of other State and

Federal projects in the vicinity.

5.2.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.2.1.2.1 Direct

Compared to the No Action Alternative, implementing Alternative 5 (NER Plan)

would restore a total of 5,840 acres on Raccoon, Timbalier, Trinity, and Whiskey

Islands. This action would restore these barrier islands to their minimal

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geormorphological form thereby enabling, consistent with Stone (2005), these

barrier islands to absorb wave energy during storms and fair-weather conditions

and provide some storm surge protection for the interior marshes within the basin,

which would decrease land loss erosion rates.

Additional direct impacts would be related to hydrologic connectivity between the

barrier island restoration sites, the Gulf of Mexico (GOM), and surrounding bays

which would be temporarily disrupted by the construction of retention dikes for

beach, dune and marsh restoration. However, retention dikes would be designed to

naturally degrade following completion of construction thereby restoring hydrologic

connectivity with GOM and surrounding bays.

5.2.1.2.2 Indirect

Compared to the No Action Alternative, indirect impacts of restoring 2,781 net

acres of barrier habitats by implementing Alternative 5 (NER Plan) would reduce

(consistent with Stone (2005)), to some undetermined level, potential adverse

impacts associated with increased storm surge and wave potential to the

Terrebonne basin interior estuarine wetlands. The existing segmented breakwaters

on Raccoon Island would continue to reduce storm wave action, which would

encourage deposition of suspended sediments behind these features. The 1,200-ft

long terminal groin on Raccoon Island would intercept the net longshore sediment

flux, thereby retaining sediment on the beach up-drift of the groin. The terminal

groin would reduce longshore erosion by capturing sediments that would otherwise

be lost through offshore transport and deposition.

Wave Conditions

Impacts of sand mining on wave transformation over Ship Shoal was investigated

by Stone and Xu (1996) and Stone (2000) and reported in MMS (2004). Stone and

Xu (1996) conducted a wave modeling analysis using STWAVE to evaluate the

effects of large-scale removal of sand from various portions of Ship Shoal. The

approach used in the 1996 study centered on the removal of the entire shoal

complex using the available bathymetric data for the shoal and surrounding area.

The total volume of sand numerically extracted from the shoal for the modeling

analysis was over 1.4 billion cy which included up to a 6-meter thick section of sand

being removed from the western portion of the shoal.

The STWAVE model analysis conducted by Stone and Xu (1996) indicated spatial

differences in the magnitude of wave heights across the Ship Shoal. The magnitude

in wave heights due to shoal removal were less on the east side of the shoal

compared to the west side. Wave height changes on the east side of the shoal were

reported to be insignificant during severe storms and even less noticeable under fair

weather conditions. During severe storm conditions, the model indicated wave

breaking does not occur on the east end of the shoal near South Pelto Blocks 12 and

13 because of the greater water depths. The STWAVE results did show some

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increased wave heights in the central and western portions of the shoal but the

overall model results indicated that the entire removal of the shoal would not have

a significant impact on wave energy conditions along the nearshore zone (MMS

2004).

A subsequent study by Stone et al. (2009) investigated the impacts of sand mining

on hydrodynamics and sediment transport on Ship Shoal using two case studies.

Case study A compared the hydrodynamics of the region under two bathymetric

configurations: one with the shoal and the other with the shoal completely removed.

Case study B utilized four different sand mining scenarios which mimicked

proposed restoration project borrow area configurations (Table 5-3). Specifically,

they examined wave, current variability, and sediment transport over the shoal

under different barrier island restoration/mining scenarios under a winter storm

and tropical cyclone event (Table 5-2). The researchers looked at mining at three

areas of Ship Shoal, namely, South Pelto Block 12/13, SS Block 88/89, and SS

Blocks 84/85/98/99.

Table 5-3. Ship Shoal mining scenarios (Stone et al. 2009).

Table 5-4. Maximal difference in magnitude of hydrodynamic parameters

between actual bathymetry and hypothetical bathymetry. Top low;

Maximal difference in absolute magnitude of each parameter. Bottom low:

Maximal values in magnitude of each parameter during model duration

(Stone et al. 2009).

Storm Case Wave height

Surface

currents

(m/s)

Bottom

currents

(m/s)

RI

N m-2

Winter storms B2 0.09

1.19

0.17

0.59

0.03

0.20

0.02

0.82

B4 0.04

1.30

0.11

0.49

0.06

0.15

0.02

0.62

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Storm Case Wave height

Surface

currents

(m/s)

Bottom

currents

(m/s)

RI

N m-2

B5 0.03

1.67

0.16

0.10

0.06

0.10

0.02

0.60

Hurricane Lili B2 0.07

1.52

0.09

0.97

0.04

0.33

0.01

1.10

B4 0.04

2.06

0.15

0.75

0.07

0.22

0.08

1.16

B5 0.07

3.47

0.05

0.06

0.03

0.15

0.04

1.39

Stone et al.s (2009) modeling results indicate that Ship Shoal has significant

influence on wave dissipation but suggest that neither large-scale nor small-scale

sand mining should result in abrupt changes in current patterns. The results

indicate that large-scale sand dredging would have profound impact on waves as

shown on Figure 5-1 as well as on sediment suspension. Based on this analysis,

large scale mining of Ship Shoal is not recommended. However, Stone et al.s (2009)

results indicate that small-scale sand mining, based on the sand mining scenarios

presented in Table 5-3, is not expected to profoundly impact hydrodynamics or

sediment transport over Ship Shoal.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

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Figure 5-1. Wave height and vector distributions for case Study A: (a, b) HS=6m, TP =11s, Wave

direction=135 (degree). (c,d) HS=3m, TP =7s, Wave direction=135 (degree), (e,f) HS=1m, TP =5s, Wave

direction=135 (degree). Top figures represent the results with the shoal and bottom figures representthe result without the shoal (Stone et al. 2009).

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5.2.1.2.3 Cumulative

Cumulative impacts would be the incremental impacts to coastal processes, flow

and water levels from implementing Alternative 5 (NER Plan) when added to all

past, present and reasonably foreseeable barrier restoration efforts. Alternative 5

(NER Plan) would restore the geomorphologic form and ecological function to a net

total of 2,781 acres of Terrebonne barrier island resources. Restoration of the

geomorphologic form to Raccoon, Whiskey, Trinity and Timbalier Islands would,

consistent with Stone (2005), enable these barrier islands to maintain their function

of absorbing wave energy during storms and fair-weather conditions and provide

some undetermined level of storm surge protection and reduction of wave potential

for the Terrebonne interior estuarine marshes, which would decrease interior land

loss erosion rates. These incremental impacts would be in addition to similar

impacts for other barrier island restoration efforts across the Louisiana coastal

area.

The existing segmented breakwaters on Raccoon Island, in combination with other

existing breakwaters such as those at Port Fouchon, Louisiana, would continue to

reduce storm wave action, thereby enabling the deposition of suspended sediments

behind these features.

The proposed 1,200-ft long terminal groin on the west end of Raccoon Island would

intercept the net longshore sediment flux, thereby retaining sediments on the beach

up-drift of the groin. The proposed terminal groin on the west end of Raccoon

Island would complement the proposed CWPPRA TE-48 terminal groin on the east

end of Raccoon Island.

The incremental impacts of implementing Alternative 5 (NER Plan) would be in

synergistic combination to impacts and benefits for overall net acres of barrier

resources created, nourished, restored, and/or protected by other Federal, State,

local, and private restoration efforts.

5.2.1.3 Alternative 11: Whiskey (Plan C)

5.2.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to coastal processes, flows

and water levels of implementing Alternative 11 would be similar to those described

for the Whiskey Island component of Alternative 5 (NER Plan), but to a much lesser

degree. Alternative 11 would restore the geomorphologic form and ecological

function to Whiskey Island resulting in an initial island of 1,272 acres.

5.2.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) but to a lesser degree. Alternative 11 would

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restore a net total of 527 acres of barrier island habitat. Consistent with Stone

(2005), restoration of Whiskey Island would absorb wave energy during storms and

fair-weather conditions and provide some storm surge protection, but to a much

lesser degree than Alternative 5 (NER Plan) for the Terrebonne basin interior

estuarine wetlands. The interior land loss erosion rates would see a similarly less

proportional decrease as compared to Alternative 5 (NER Plan).

5.2.1.3.3 Cumulative

Cumulative impacts of implementing Alternative 11 to coastal processes, flow and

water levels would be similar to those described for the Whiskey Island component

of Alternative 5 (NER Plan) but to a much lesser degree for restoration of a net total

of 527 acres. The incremental impacts of implementing Alternative 11 would be in

synergistic combination to impacts and benefits for overall net acres of barrier

resources created, nourished, restored, and/or protected by other Federal, State,

local, and private restoration efforts.

5.2.1.4 Alternative 2: Timbalier (Plan E)

5.2.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to coastal processes, flows

and water levels of implementing Alternative 2 would be similar to those described

for the Timbalier Island component of Alternative 5 (NER Plan), but to a much

lesser degree. Alternative 2 would restore the geomorphologic form and ecological

function to Timbalier Island resulting in an initial island of 2,630 acres.

5.2.1.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) but to a lesser degree. Alternative 2 would

restore a net total of 1,324 acres of barrier island habitat. Consistent with Stone

(2005), restoration of Timbalier Island would absorb wave energy during storms and

fair-weather conditions and provide some storm surge protection, but to a much

lesser degree than Alternative 5 (NER Plan) for the Terrebonne basin interior

estuarine wetlands. The interior land loss erosion rates would see a similarly less

proportional decrease as compared to Alternative 5 (NER Plan).

5.2.1.4.3 Cumulative

Cumulative impacts of implementing Alternative 2 to coastal processes, flow and

water levels would be similar to those described for the Timbalier Island component

of Alternative 5 (NER Plan) but to a much lesser degree for restoration of a net total

of 1,324 acres. The incremental impacts of implementing Alternative 2 would be in

synergistic combination to impacts and benefits for overall net acres of barrier

resources created, nourished, restored, and/or protected by other Federal, State,

local, and private restoration efforts.

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5.2.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.2.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to coastal processes, flows

and water levels of implementing Alternative 3 would be similar to those described

for the Whiskey and Timbalier Islands components of Alternative 5 (NER Plan), but

to a much lesser degree. Alternative 3 would initially restore the geomorphologic

form and ecological function to a 1,272-acre Whiskey Island and 2,630-acre

Timbalier Island.

5.2.1.6 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) but to a lesser degree. Alternative

3 would restore a net total of 1,851 acres of barrier island habitat. Consistent with

Stone (2005), restoration of Whiskey and Timbalier Islands would absorb wave

energy during storms and fair-weather conditions and provide some storm surge

protection, but to a lesser degree than Alternative 5 (NER Plan) for the Terrebonne

basin interior estuarine wetlands. The interior land loss erosion rates would see a

similarly less proportional decrease as compared to Alternative 5 (NER Plan).

5.2.1.6.1 Cumulative

Cumulative impacts of implementing Alternative 3 to coastal processes, flow and

water levels would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) but to a lesser degree with

restoration of a net total of 1,851 acres of barrier island habitat. The incremental

impacts of implementing Alternative 3 would be in synergistic combination to

impacts and benefits for overall net acres of barrier resources created, nourished,

restored, and/or protected by other Federal, State, local, and private restoration

efforts.

5.2.1.7 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.2.1.7.1 Direct

Compared to the No Action Alternative, direct impacts to coastal processes, flows

and water levels of implementing Alternative 4 would be similar to those described

for the Whiskey, Trinity and Timbalier Islands components of Alternative 5 (NER

Plan), but to a lesser degree. Alternative 4 would initially restore the

geomorphologic form and ecological function to a 1,272-acre Whiskey Island, 1,149-

acre Trinity Island and 2,630-acre Timbalier Island.

5.2.1.7.2 Indirect

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Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) but to a lesser degree.

Alternative 4 would restore a net total of 2,140 acres of barrier island habitat.

Consistent with Stone (2005), restoration of Whiskey, Trinity and Timbalier Islands

would absorb wave energy during storms and fair-weather conditions and provide

some storm surge protection, but to a lesser degree than Alternative 5 (NER Plan)

for the Terrebonne basin interior estuarine wetlands. The interior land loss erosion

rates would see a similarly less proportional decrease as compared to Alternative 5

(NER Plan).

5.2.1.7.3 Cumulative

Cumulative impacts of implementing Alternative 4 to coastal processes, flow and

water levels would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) but to a lesser degree

with restoration of a net total of 2,140 acres of barrier island habitat. The

incremental impacts of implementing Alternative 3 would be in synergistic

combination to impacts and benefits for overall net acres of barrier resources

created, nourished, restored, and/or protected by other Federal, State, local, and

private restoration efforts.

5.2.2 Sediment and Erosion

5.2.2.1 No action Alternative (Future without Project Conditions)

5.2.2.1.1 Direct

Little information concerning sediment exchange between the Gulf of Mexico and

the Terrebonne Basin coastal wetlands is available. Roberts et al. (1987) suggest

that storm passage over the coastal boundary provides for accretion if there is a

sediment supply offshore. However, if there is no sediment supply, erosion is likely

to occur. Estuaries with large openings to the Gulf of Mexico contain higher

percentages of sand and course silt than equally large bodies with no connection to

the Gulf (Barret, 1971). The No Action Alternative would have no direct impacts on

sedimentation and erosion. Without any action, approximately 3,220 acres of

existing barrier sediment resources from the seven island Terrebonne Basin barrier

system (East Timbalier, Timbalier, Trinity, East Island, Wine, Whiskey and

Raccoon Island) would likely continue to erode similar to historic erosion rates

(Table 4-2 and 4-3) and eventually convert into shallow open water bottoms.

Sediments eroded from these barrier islands would be lost offshore.

5.2.2.1.2 Indirect

Under the No Action Alternative the Terrebonne Basin barrier islands would

continue to erode and migrate (Williams et al. 1992). According to Hoyt and Henry

(1967) sedimentary modifications produced by island migration would include

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textural changes, shape of the deposit, and steepening and reorientation of

stratification. The re-working of sediments which accompany island migration could

potentially alter the texture of sediment, depending on the material available for

deposition and on the composition of the sediment being reworked. The primary

impacts of barrier island migration would be modification of stratification.

According to Britton and Morton (1993), barrier islands such as the Terrebonne

barrier system play an important role in defining the physical boundary between

the marine and estuarine systems. Sandy beaches, composed of almost infinite

numbers of particles, experience considerable wave exposure. The net transport of

these particles is landward with constructive waves. Particles moved landward may

be moved high upon the shore where they become soil stabilized by vegetation.

Successive layers of the material accumulate until equilibrium with the topography

is achieved. Britton and Morton (1993) indicate, however, that there is an energy

threshold beyond which wave cease being constructive and become destructive on a

soft shore. During storms, sediment is removed from a beach and dumped offshore.

Destructive waves have relatively greater kinetic energy than constructive waves

and sand particles are held in suspension longer, allowing backwash to remove at

least some of them downshore.

Britton and Morton (1993) further indicate that the ultimate character of a soft

shore, including its slope, stability and capacity as a habitat, is dependent upon the

size and distribution of the particles that comprise it. On low energy mudflats, little

sorting occurs; whereas, on high energy beaches sorting capacity is greatly

enhanced. Additional sorting is achieved by the swash and backwash. On wave

sorted beaches, the coarsest grains occur at the top of the beach and the finest at

the bottom typically below low water.

Sediment quality is important due to the indirect role that sediments play in

supporting animal and plant community productivity (LDEQ, 2005). The

productivity of green plants, algae, and bacteria are the foundation of food webs

upon which higher aquatic and terrestrial organisms depend (Day et al. 1989).

Sediments provide essential habitats for epibenthic (organisms which live on

sediments) and infaunal (organisms which live in sediments) invertebrates and

demersal fish, which represent important food sources for amphibians, reptiles, fish,

birds, and mammals (Britton and Morton 1993). In addition, many fish and

amphibian species utilize sediments at stages in their life cycles for the purposes of

spawning, incubation, refuge, and over-wintering (Day et al. 1989; Britton and

Morton 1993; LDEQ, 2005).

Without any action, approximately 3,220 acres of existing barrier resources from

the seven island Terrebonne Basin barrier system (East Timbalier, Timbalier,

Trinity, East Island, Wine, Whiskey and Raccoon Island) would likely continue to

degrade, fragment and eventually convert into shallow open water bottoms. The

Terrebonne Basin barrier island system would continue to experience higher wave

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energy levels and associated shoreline erosion in the adjacent bays (Stone and

McBride 1998, Stone et al 2003, and Stone et al. 2005).

If the Terrebonne Basin barrier island system is not restored, the adjacent

estuarine bay systems, along with their sediment resources, will continue to be

transformed into marine open water habitat. The loss of barrier resources would

adversely impact important transitional habitat between estuarine and marine

environments; essential fish habitat (EFH); unique wildlife habitat (e.g., nursery,

nesting, feeding, and roosting habitats); and critical wintering habitat for the

threatened piping plover. The continued degradation and eventual loss of soil

resources would result in the loss of fish and wildlife habitat which would likely

increase competition between and within various fish and wildlife species for

diminishing habitat resources. The loss of vegetated wetlands would also result in

a loss in primary productivity and eventually result in conversion of the existing

back bay estuarine system into more marine open water system.

5.2.2.1.3 Cumulative

The No Action Alternative would have cumulative impacts on sediments and

erosion in which sediment quality, quantity, and sediment source would be affected.

Erosion rates would increase to the point that the barrier habitats would erode and

sedimentation would decrease forcing these critical habitats to eventually no longer

exist. Sediment quality, an important role that sediments play in supporting

community productivity, would be altered in size and the availability of sediments

that are needed for healthy marsh, beach, and dune habitats. When all intertidal

habitats along the barrier islands disappear, the remaining habitat types will

increase in erosion and disappear as well. Storm surge will then reach further

inland with the absence of these barrier islands resulting in an increase in erosion

along inland marshes.

5.2.2.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.2.2.2.1 Direct

Compared to the No Action Alternative, implementing Alternative 5 (NER Plan)

would initially restore Raccoon, Timbalier, Trinity, and Whiskey Islands to their

minimal geormorphological form and ecological function utilizing approximately

67,184,714 cy of borrow sediments obtained from several sources, including Ship

Shoal, Raccoon, Whiskey 3a, South Pelto, and New Cut. Borrow sediments from the

South Pelto borrow area are characterized as D50 grain size 0.15 to 0.2 mm, with

less than 5% silt in upper stratigraphic layer. Other borrow area sediments would

be comparable. Impacts to sediments and erosion would primarily be indirect.

5.2.2.2.2 Indirect

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Compared to the No Action Alternative, indirect impacts of restoring 2,781 net

acres of barrier habitats by implementing Alternative 5 (NER Plan) would be

related to the geomorphologic character of the restored barrier islands. Indirect

impacts to sediments and erosion would be primarily related to size and

distribution of sediment particles.

Following construction, sediments would continue to be subjected to high energy

wave sorting as well as additional sorting achieved by the swash and backwash.

The coarsest sediment grains would occur at the top of the beach and the finest at

the bottom typically below low water. Erosion rates (Tables 4-2 and 4-3), adapted

from Williams et al. (1992), where calculated for each barrier island component

within Alternative 5 (NER Plan). Erosive forces, such as waves and storms, would

continue. However, the coarser grained borrow sediments would be expected to

better withstand erosive forces (personal communication Dr. Louis Del Britsch,

USACE Geologist, 1 September 2010). Restoration of fragmented beach and dune

would reduce erosion of the back barrier marsh. In addition, restoration with the

higher quality borrow sediments would enable, consistent with Stone (2005), the

restored barrier islands to better absorb wave energy during storms and fairweather conditions and provide some storm surge protection for the interior

marshes within the basin, which would decrease land loss erosion rates.

The character of the restored barrier islands, including their slope, stability and

capacity as a habitat, would be dependent upon the size and distribution of the

sediment particles that comprise it. A portion of the total 67,184,714 cy of borrow

sediments placed for restoration of the four barrier islands would be redistributed,

via natural coastal longshore transport process, throughout the Terrebonne barrier

island system over the 50-year period of analysis.

The proposed terminal groin, as well as the existing segmented breakwaters, on

Raccoon Island would function to intercept the net longshore sediment flux, thereby

retaining sediments on the beach up-drift of the groin and within the tombolos

shoreward of the breakwaters. Sedimentation rates along Whiskey, Trinity and

Timbalier Islands would likely remain unchanged.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.2.2.2.3 Cumulative

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Cumulative impacts would be the incremental impacts to sediment and erosion

from implementing Alternative 5 (NER Plan) when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 5 (NER Plan) would

restore the geomorphologic form and ecological function to a net total of 2,781 acres

of Terrebonne barrier island resources. Restoration of the geomorphologic form to

these four barrier islands would, consistent with Stone (2005), enable these barrier

islands to maintain their function of absorbing wave energy during storms and fairweather conditions and provide some undetermined level of storm surge protection

and reduction of wave potential for the Terrebonne interior estuarine marshes,

which would decrease interior land loss erosion rates. These incremental impacts

would be in addition to impacts and benefits for acres of barrier islands created,

nourished, restored, and/or protected by other Federal, State, local, and private

restoration efforts.

5.2.2.3 Alternative 11: Whiskey (Plan C)

5.2.2.3.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

11 would be similar to those described for the Whiskey Island component of

Alternative 5 (NER Plan). Whiskey Island would be restored to its minimal

geormorphological form and ecological function utilizing approximately 26,660,249

cy of borrow sediments obtained from several sources, including Ship Shoal and

Whiskey borrow areas.

5.2.2.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER) but to a lesser degree, including the natural

redistribution of a portion of the total 23,599,804 cy of sediments throughout the

Terrebonne Basin barrier island system over the 50-year period of analysis. The

coarser grained borrow sediments would be expected to better withstand erosive

forces (personal communication Dr. Louis Del Britsch, USACE Geologist,

September 1, 2010). In addition, restoration of fragmented beach and dune on

Whiskey Island would reduce erosion of the back barrier marsh.

Consequently, restoration with the higher quality borrow sediments would enable,

consistent with Stone (2005), the restored Whiskey Island to better absorb wave

energy during storms and fair-weather conditions and provide some storm surge

protection for the interior marshes within the basin, which would decrease land loss

erosion rates, although to a much less extent than Alternative 5 (NER Plan).

Additional indirect impacts would be the prevention of a net total of 527 acres of

barrier habitats and associated sediments being lost to erosion and converting to

water bottoms over the 50-year period of analysis.

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5.2.2.3.3 Cumulative

Cumulative impacts of implementing Alternative 11 would be similar to those

described for the Whiskey Island component of Alternative 5 (NER Plan) including

the natural redistribution of a portion of the 26,940,240 cy of sediments throughout

the Terrebonne Basin barrier island system as well as the prevention of a net total

of 527 acres of barrier sediments being lost to erosion and conversion to water

bottoms over the 50-year period of analysis. These incremental cumulative impacts

of Alternative 11 would be in addition to impacts and benefits to sediment and

erosion for barrier islands created, nourished, restored, and/or protected by other

Federal, State, local, and private restoration efforts.

5.2.2.4 Alternative 2: Timbalier (Plan E)

5.2.2.4.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

2 would be similar to those described for the Timbalier Island component of

Alternative 5 (NER Plan). Timbalier Island would be restored to its minimal

geomorphologic form and ecological function utilizing approximately 20,246,338 cy

of sediments be removed from South Pelto  6, Whiskey  3, and New Cut  5

borrow areas.

5.2.2.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) but to a lesser degree, including the natural

redistribution of a portion of the total 20,246,338 cy of sediments throughout the

Terrebonne Basin barrier island system over the 50-year period of analysis.

Additional indirect impacts would be the prevention of a net total of 1,324 acres of

barrier habitats and associated sediments being lost to erosion and converting to

water bottoms over the 50-year period of analysis. The coarser grained borrow

sediments would be expected to better withstand erosive forces (personal

communication Dr. Louis Del Britsch, USACE Geologist, September 1, 2010). In

addition, restoration of fragmented beach and dune on Whiskey Island would

reduce erosion of the back barrier marsh.

Consequently, restoration with the higher quality borrow sediments would enable,

consistent with Stone (2005), the restored Whiskey Island to better absorb wave

energy during storms and fair-weather conditions and provide some storm surge

protection for the interior marshes within the basin, which would decrease land loss

erosion rates, although to a much less extent than Alternative 5 (NER Plan).

Additional indirect impacts would be the prevention of a net total of 1,324 acres of

barrier habitats and associated sediments being lost to erosion and converting to

water bottoms over the 50-year period of analysis.

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5.2.2.4.3 Cumulative

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including the natural redistribution of a

portion of the 20,246,338 cy of sediments throughout the Terrebonne Basin barrier

island system as well as the prevention of a net total of 1,324 acres of barrier

sediments being lost to erosion and conversion to water bottoms over the 50-year

period of analysis. These incremental cumulative impacts would be in addition to

impacts and benefits to sediment and erosion for barrier islands created, nourished,

restored, and/or protected by other Federal, State, local, and private restoration

efforts.

5.2.2.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.2.2.5.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

3 would be similar to those described for the Whiskey and Timbalier Islands

components of Alternative 5 (NER Plan). Whiskey and Timbalier Islands would be

restored to their minimal geomorphologic form and ecological function utilizing a

total of approximately 43,846,142 cy of sediments removed from Ship Shoal, South

Pelto, Whiskey 3a, and New Cut borrow areas.

5.2.2.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER) but to a lesser degree, including the

natural redistribution of a portion of the total 43,846,142 cy of sediments

throughout the Terrebonne Basin barrier island system over the 50-year period of

analysis. Additional indirect impacts would be the prevention of a net total of 1,851

acres of barrier habitats and associated sediments being lost to erosion and

converting to water bottoms over the 50-year period of analysis. The coarser

grained borrow sediments would be expected to better withstand erosive forces

(personal communication Dr. Louis Del Britsch, USACE Geologist, September 1,

2010). In addition, restoration of fragmented beach and dune on Whiskey and

Timbalier Islands would reduce erosion of the back barrier marsh for these islands.

Consequently, restoration with the higher quality borrow sediments would enable,

consistent with Stone (2005), the restored Whiskey and Timbalier Islands to better

absorb wave energy during storms and fair-weather conditions and provide some

storm surge protection for the interior marshes within the basin, which would

decrease land loss erosion rates, although to a much less extent than Alternative 5

(NER Plan). Additional indirect impacts would be the prevention of a net total of

1,851 acres of barrier habitats and associated sediments being lost to erosion and

converting to water bottoms over the 50-year period of analysis.

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5.2.2.5.3 Cumulative

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) including the natural

redistribution of a portion of the 43,846,142 cy of sediments throughout the

Terrebonne Basin barrier island system as well as the prevention of a net total of

1,851 acres of barrier sediments being lost to erosion and conversion to water

bottoms over the 50-year period of analysis. These incremental cumulative impacts

would be in addition to impacts and benefits to sediment and erosion for barrier

islands created, nourished, restored, and/or protected by other Federal, State, local,

and private restoration efforts.

5.2.2.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.2.2.6.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

4 would be similar to those described for the Whiskey, Trinity and Timbalier

Islands components of Alternative 5 (NER Plan). Whiskey, Trinity and Timbalier

Islands would be restored to their minimal geomorphologic form and ecological

function utilizing a total of approximately 55,246,837 of sediments removed from

Ship Shoal, South Pelto, Whiskey 3a, Raccoon Island, and New Cut  5 borrow

areas.

5.2.2.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity, and

Timbalier Islands components of Alternative 5 (NER Plan) but to a lesser degree,

including the natural redistribution of a portion of the total 55,246,837 cy of

sediments throughout the Terrebonne Basin barrier island system over the 50-year

period of analysis. Additional indirect impacts would be the prevention of a net

total of 2,140 acres of barrier habitats and associated sediments being lost to

erosion and converting to water bottoms over the 50-year period of analysis. The

coarser grained borrow sediments would be expected to better withstand erosive

forces (personal communication Dr. Louis Del Britsch, USACE Geologist,

September 1, 2010). In addition, restoration of fragmented beach and dune on

Whiskey, Trinity and Timbalier Islands would reduce erosion of the back barrier

marsh for these islands.

Consequently, restoration with the higher quality borrow sediments would enable,

consistent with Stone (2005), the restored Whiskey, Trinity and Timbalier Islands

to better absorb wave energy during storms and fair-weather conditions and provide

some storm surge protection for the interior marshes within the basin, which would

decrease land loss erosion rates, although to a much less extent than Alternative 5

(NER Plan). Additional indirect impacts would be the prevention of a net total of

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2,140 acres of barrier habitats and associated sediments being lost to erosion and

converting to water bottoms over the 50-year period of analysis.

5.2.2.6.3 Cumulative

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) including the natural

redistribution of a portion of the 55,246,837 cy of sediments throughout the

Terrebonne Basin barrier island system as well as the prevention of a net total of

2,140 acres of barrier sediments being lost to erosion and conversion to water

bottoms over the 50-year period of analysis. These incremental cumulative impacts

would be in addition to impacts and benefits to sediment and erosion for barrier

islands created, nourished, restored, and/or protected by other Federal, State, local,

and private restoration efforts.

5.2.3 Water Use and Supply

5.2.3.1 No action Alternative (Future without Project Conditions)

5.2.3.1.1 Direct

The Study Area is remote and uninhabited. Hence, there would be no direct impacts

of the No Action Alternative on water use and supply. Not implementing the

Terrebonne Basin barrier island restoration would result in the persistence of

existing conditions.

5.2.3.1.2 Indirect

There would be no indirect impacts of the No Action Alternative on the water use

and supply within the Study Area.

5.2.3.1.3 Cumulative

There would be no cumulative impacts of the No Action Alternative on water use

and supply within the Study Area.

5.2.3.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.2.3.3

5.2.3.3.1 Direct

There would be no direct impact on the water supplies in this area.

5.2.3.3.2 Indirect

There would be no indirect impact on the water supplies in this area.

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5.2.3.3.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.2.3.4 Alternative 11: Whiskey (Plan C)

5.2.3.4.1 Direct

There would be no direct impact on the water supplies in this area.

5.2.3.4.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.2.3.4.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.2.3.5 Alternative 2: Timbalier (Plan E)

5.2.3.5.1 Direct

There would be no direct impact on the water supplies in this area.

5.2.3.5.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.2.3.5.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.2.3.6 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.2.3.6.1 Direct

There would be no direct impact on the water supplies in this area.

5.2.3.6.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.2.3.6.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.2.3.7 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.2.3.7.1 Direct

There would be no direct impact on the water supplies in this area.

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5.2.3.7.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.2.3.7.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.2.4 Groundwater

5.2.4.1 No action Alternative (Future without Project Conditions)

5.2.4.1.1 Direct

The Study Area is remote and uninhabited. Hence, there would be no direct impacts

of the No Action Alternative on groundwater. Not implementing barrier restoration

features would result in the persistence of existing conditions.

5.2.4.1.2 Indirect

There would be no indirect impact on the groundwater in the Study Area.

5.2.4.1.3 Cumulative

There would be no cumulative impact on the groundwater supplies in the Study

Area.

5.2.4.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.2.4.2.1 Direct

There would be no direct impact on the groundwater in the Study Area.

5.2.4.2.2 Indirect

There would be no indirect impact on the groundwater in the Study Area.

5.2.4.2.3 Cumulative

There would be no cumulative impact on the groundwater supplies in the Study

Area.

5.2.4.3 Alternative 11: Whiskey (Plan C)

5.2.4.3.1 Direct

There would be no direct impact on the groundwater in the Study Area.

5.2.4.3.2 Indirect

There would be no indirect impact on the groundwater in the Study Area.

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5.2.4.3.3 Cumulative

There would be no cumulative impact on the groundwater supplies in the Study

Area.

5.2.4.4 Alternative 2: Timbalier (Plan E)

5.2.4.4.1 Direct

There would be no direct impact on the groundwater in the Study Area.

5.2.4.4.2 Indirect

There would be no indirect impact on the groundwater in the Study Area.

5.2.4.4.3 Cumulative

There would be no cumulative impact on the groundwater supplies in the Study

Area.

5.2.4.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.2.4.5.1 Direct

There would be no direct impact on the groundwater in the Study Area.

5.2.4.5.2 Indirect

There would be no indirect impact on the groundwater in the Study Area.

5.2.4.5.3 Cumulative

There would be no cumulative impact on the groundwater supplies in the Study

Area.

5.2.4.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.2.4.6.1 Direct

There would be no direct impact on the groundwater in the Study Area.

5.2.4.6.2 Indirect

There would be no indirect impact on the groundwater in the Study Area.

5.2.4.6.3 Cumulative

There would be no cumulative impact on the groundwater supplies in the Study

Area.

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5.3 WATER QUALITY AND SALINITY

5.3.1 Water Quality

5.3.1.1 No action Alternative (Future without Project Conditions)

5.3.1.1.1 Direct

The No Action Alternative, not implementing the Terrebonne Basin Barrier

Shoreline restoration, would have no direct impact on water quality resources.

Existing conditions would likely continue into the future.

5.3.1.1.2 Indirect

Without implementation of the Terrebonne Basin Barrier Shoreline restoration, the

Terrebonne Basin would still be affected by natural and anthropogenic activities

having both beneficial and detrimental effects to water quality. Some of these

activities include: other restoration efforts, including other CWPPRA, USACE,

NRCS, and LDNR projects; Federal and State water quality management programs;

programs addressing hypoxia in the northern Gulf of Mexico; the continuation of

erosion and subsidence of coastal Louisiana; oil and gas development; and Federal,

State, and municipal flood-damage reduction and navigation projects. The future of

water quality for coastal Louisiana is dependent on a responsible, watershed

approach to managing these activities.

5.3.1.1.3 Cumulative

A majority of the present and future activities would persist without the Terrebonne

Basin Barrier Shoreline restoration and would affect surface water quality

conditions throughout Louisiana. The cumulative impacts associated with these

activities without the Terrebonne Basin Barrier Shoreline restoration are included

below:

Passage of the Federal Water Pollution Control Act (FWPCA) in 1948 and its

amendments, including the CWA and the Water Quality Act of 1987, as well as the

establishment of State and Federal environmental protection agencies, resulted in

water pollution control regulations, including:

 The National Pollutant Discharge Elimination System (NPDES) permit

program controls water pollution. In 1997 the USEPA granted NPDES

delegation to the Louisiana Department of Environmental Quality (LDEQ),

which is known as the Louisiana Pollutant Discharge Elimination System

(LPDES).

 The LDEQ Nonpoint Source Pollution Program is continuing to implement

watershed initiatives to address nonpoint source pollution sources such as

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agriculture, home sewage treatment, hydromodification, urban runoff,

construction activities, and resource extraction.

 The LDNRs Coastal Nonpoint Pollution Program is responsible for

identifying Best Management Practices (BMPs) appropriate for all applicable

pollutant source categories and carrying out initiatives of public education,

technical assistance, and development of enforcement protocols.

 Total Maximum Daily Loads (TMDLs); Section 303(d) of the CWA requires

states to identify, list, and rank for development of TMDLs for waters that do

not meet applicable water quality standards after implementation of

technology-based controls.

 The Barataria-Terrebonne National Estuary Program (BTNEP) is a coalition

of government, private, and commercial interests active in

collecting/publishing information, as well as educating the public to protect

the Barataria and Terrebonne Basins.

 The USEPA-formed Hypoxia Task Force is leading a national task force to

address hypoxia in the northern Gulf of Mexico, which is attributed to the

excessive nutrients in the Mississippi  Atchafalaya River Basin.

These programs would continue to develop with or without the Terrebonne Basin

Barrier Shoreline restoration to ensure that Louisiana public health and natural

resources remain protected. With these programs in place, it is expected that water

quality conditions within the State of Louisiana would likely improve overall.

However, activities with the potential for negative effects on water quality would

also continue to occur with or without the proposed restoration features. In

addition, present and future Federal, State, local, and private ecosystem restoration

projects would probably improve water quality conditions throughout Louisiana.

5.3.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.3.1.2.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

5 (NER Plan) would primarily result from the discharge of 67,184,714 cy of dredged

material and associated effluent waters during construction. Proposed restoration

features would not result in either long-term or short-term water quality impacts to

the adjacent aquatic ecosystem. Potential impacts of dredged material effluent

discharges would include increased turbidity and decreased oxygen concentrations,

are expected to be short-lived and would likely result in temporary and minor

impacts to water quality, if any.

5.3.1.2.2 Indirect

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Compared to the No Action Alternative, indirect impacts of implementing

Alternative 5 (NER Plan) would result in minor improvements to water quality as

barrier wetlands would serve as natural filters for improving water quality (Day et

al. 1989). A net total of 1,459 acres of vegetated barrier habitats would be

restored/created that would contribute to improving water quality. In addition,

restoration of the four islands within the Terrebonne Basin barrier island system

that would provide a more robust marine-estuarine geomorphic boundary that

would contribute to restricting higher salinity Gulf of Mexico waters from entering

fresher interior estuarine areas thereby helping stabilize salinity regimes in the

lower portions of the Terrebonne Basin.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.3.1.2.3 Cumulative

Compared to the No Action Alternative, cumulative impacts of implementing

Alternative 5 (NER Plan) would contribute towards the restoration of the

Terrebonne Basin barrier system which would serve, in part, to protect coastal

wetland areas from erosive forces. Restoring four of the seven Terrebonne Basin

barrier islands would contribute to improving water quality within lower portions of

the Terrebonne Basin.

Working synergistically with other restoration efforts (e.g., CWPPRA projects, LCA

Convey Atchafalaya River water to northern Terrebonne marshes, and others)

Alternative 5 (NER Plan) would contribute, to some unknown extent, to the

stabilization of the marine  estuarine system and salinity regimes within the lower

Terrebonne Basin. Stabilizing salinity regimes would contribute to multiple

natural resource users, resource managers, commercial and recreational fisheries

managers, and other water users in making long-term water quality management

decisions.

The incremental impacts of implementing Alternative 5 (NER Plan) would be in

synergistic combination to water quality impacts and benefits for overall net acres

of barrier resources created, nourished, restored, and/or protected by other Federal,

State, local, and private restoration efforts.

5.3.1.3 Alternative 11: Whiskey (Plan C)

5.3.1.3.1 Direct

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Compared to the No Action Alternative, direct impacts water quality of

implementing Alternative 11 would be similar, but to a much lesser degree, to those

described for the Whiskey Island component of Alternative 5 (NER Plan). The

discharge of 23,599,804 cy of dredged material and associated effluent waters

during construction would include increased turbidity and decreased oxygen

concentrations, which are expected to be short-lived and would likely result in

temporary and minor impacts to water quality, if any.

5.3.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) but to a lesser degree. A net total of 311

acres of vegetated barrier habitats would be restored/created that would contribute

to improving water quality as well as contribute to developing a more robust

Terrebonne Basin barrier island system, provide a more robust marine-estuarine

geomorphic boundary, and contribute to restricting higher salinity Gulf of Mexico

waters from entering fresher interior estuarine areas thereby helping stabilize

salinity regimes in the lower portions of the Terrebonne Basin.

5.3.1.3.3 Cumulative

Compared to the No Action Alternative, the incremental cumulative impacts of

implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan) but to a lesser degree. These impacts

would contribute to improving water quality within lower portions of the

Terrebonne Basin, work synergistically with other restoration efforts contributing

to the stabilization of the marine  estuarine system and salinity regimes within

the lower Terrebonne Basin. The incremental impacts of implementing Alternative

11 would be in synergistic combination to water quality impacts and benefits for

overall net acres of barrier resources created, nourished, restored, and/or protected

by other Federal, State, local, and private restoration efforts.

5.3.1.4 Alternative 2: Timbalier (Plan E)

5.3.1.4.1 Direct

Compared to the No Action Alternative, direct impacts water quality of

implementing Alternative 2 would be similar, but to a much lesser degree, to those

described for the Timbablier Island component of Alternative 5 (NER Plan). The

discharge of 20,246,338 cy of dredged material and associated effluent waters

during construction would include increased turbidity and decreased oxygen

concentrations, which are expected to be short-lived and would likely result in

temporary and minor impacts to water quality, if any.

5.3.1.4.2 Indirect

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Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 (recommended component of construction) would be similar to those

described for the Timbalier Island component of Alternative 5 (NER Plan) but to a

lesser degree. A net total of 706 acres of vegetated barrier habitats would be

restored/created that would contribute to improving water quality as well as

contribute to developing a more robust Terrebonne Basin barrier island system,

provide a more robust marine-estuarine geomorphic boundary, and contribute to

restricting higher salinity Gulf of Mexico waters from entering fresher interior

estuarine areas thereby helping stabilize salinity regimes in the lower portions of

the Terrebonne Basin.

5.3.1.4.3 Cumulative

Compared to the No Action Alternative, the incremental cumulative impacts of

implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan) but to a lesser degree. These impacts

would contribute to improving water quality within lower portions of the

Terrebonne Basin, work synergistically with other restoration efforts contributing

to the stabilization of the marine  estuarine system and salinity regimes within

the lower Terrebonne Basin. The incremental impacts of implementing Alternative

2 would be in synergistic combination to water quality impacts and benefits for

overall net acres of barrier resources created, nourished, restored, and/or protected

by other Federal, State, local, and private restoration efforts.

5.3.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.3.1.5.1 Direct

Compared to the No Action Alternative, direct impacts water quality of

implementing Alternative 3 would be similar, but to a much lesser degree, to those

described for the Whiskey and Timbablier Islands components of Alternative 5

(NER Plan). The discharge of 43,846,142 cy of dredged material and associated

effluent waters during construction would include increased turbidity and

decreased oxygen concentrations, which are expected to be short-lived and would

likely result in temporary and minor impacts to water quality, if any.

5.3.1.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) but to a lesser degree. A net total

of 1,017 acres of vegetated barrier habitats would be restored/created that would

contribute to improving water quality as well as contribute to developing a more

robust Terrebonne Basin barrier island system, provide a more robust marineestuarine geomorphic boundary, and contribute to restricting higher salinity Gulf of

Mexico waters from entering fresher interior estuarine areas thereby helping

stabilize salinity regimes in the lower portions of the Terrebonne Basin.

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5.3.1.5.3 Cumulative

Compared to the No Action Alternative, the incremental cumulative impacts of

implementing Alternative 3 would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan) but to a lesser degree.

These impacts would contribute to improving water quality within lower portions of

the Terrebonne Basin, work synergistically with other restoration efforts

contributing to the stabilization of the marine  estuarine system and salinity

regimes within the lower Terrebonne Basin. The incremental impacts of

implementing Alternative 3 would be in synergistic combination to water quality

impacts and benefits for overall net acres of barrier resources created, nourished,

restored, and/or protected by other Federal, State, local, and private restoration

efforts.

5.3.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.3.1.6.1 Direct

Compared to the No Action Alternative, direct impacts water quality of

implementing Alternative 4 would be similar, but to a lesser degree, to those

described for the Whiskey, Trinity and Timbablier Islands components of

Alternative 5 (NER Plan). The discharge of 55,246,837 cy of dredged material and

associated effluent waters during construction would include increased turbidity

and decreased oxygen concentrations, which are expected to be short-lived and

would likely result in temporary and minor impacts to water quality, if any.

5.3.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) but to a lesser degree. A

net total of 1,12 acres of vegetated barrier habitats would be restored/created that

would contribute to improving water quality as well as contribute to developing a

more robust Terrebonne Basin barrier island system, provide a more robust marineestuarine geomorphic boundary, and contribute to restricting higher salinity Gulf of

Mexico waters from entering fresher interior estuarine areas thereby helping

stabilize salinity regimes in the lower portions of the Terrebonne Basin.

5.3.1.6.3 Cumulative

Compared to the No Action Alternative, the incremental cumulative impacts of

implementing Alternative 4 would be similar to those described for the Whiskey,

Trinity and Timbalier Islands components of Alternative 5 (NER Plan) but to a

lesser degree. These impacts would contribute to improving water quality within

lower portions of the Terrebonne Basin, work synergistically with other restoration

efforts contributing to the stabilization of the marine  estuarine system and

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salinity regimes within the lower Terrebonne Basin. The incremental impacts of

implementing Alternative 4 would be in synergistic combination to water quality

impacts and benefits for overall net acres of barrier resources created, nourished,

restored, and/or protected by other Federal, State, local, and private restoration

efforts.

5.3.2 Salinity

5.3.2.1 No action Alternative (Future without Project Conditions)

5.3.2.1.1 Direct

Barrier islands are critical in maintaining salinity gradients between the marine

and estuarine system, which in turn is vital for proper functioning of the associated

estuarine systems (Knotts, et al. 2006). The Terrebonne Basin barrier islands define

the Terrebonne Basin marine  estuarine boundary, restrict water exchange

between the marine and estuarine systems, and provide storm surge protection to

wetlands and human infrastructure, and modify currents and salinity within the

bay systems (Britton and Morton 1989; Day et al. 1989).

The No Action Alternative, not implementing the Terrebonne Basin barrier

shoreline restoration, would have no direct impacts on salinity. Existing conditions

would continue with degradation and eventual loss of the Terrebonne Basin barrier

system thereby resulting in higher salinity waters from the Gulf of Mexico to

intrusion into the lower estuarine interior wetlands and disrupting the existing

estuarine salinity gradient.

5.3.2.1.2 Indirect

Without any action, the seven island 3,220-acre Terrebonne Basin barrier system

(East Timbalier, Timbalier, Trinity, East Island, Wine, Whiskey and Raccoon

Island) would continue to degrade, fragment and eventually convert into shallow

open water bottoms. The Terrebonne Basin barrier island system would continue to

experience higher wave energy levels and associated shoreline erosion in the

adjacent bays (Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005).

Loss of the geomorphic barrier system boundary would change the tidal prism

dynamics resulting in increased interior land loss and conversion of the Terrebonne

Basin estuarine system to a more marine system thereby significantly reducing

productivity (Penland et al., 2003). Vegetation species would be dominated by more

salt tolerant species and existing salt-intolerant species would be displaced to

fresher inland areas.

If the Terrebonne Basin barrier island system is not restored, the adjacent

estuarine bay systems, along with their various significant resources, would

continue to be transformed into marine open water habitats. The loss of the

Terrebonne Basin barrier system would result in the loss of important transitional

habitat between estuarine and marine environments; essential fish habitat (EFH);

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unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting habitats); and

critical wintering habitat for the threatened piping plover. The continued

degradation and eventual loss of the Terrebonne Basin barrier system would result

in the loss of fish and wildlife habitat which would likely increase competition

between and within various fish and wildlife species for diminishing habitat

resources. The loss of vegetated wetlands would also result in a loss in primary

productivity and eventually result in conversion of the existing back bay estuarine

system into more marine open water system devoid of vegetation resources.

5.3.2.1.3 Cumulative

Louisiana has lost approximately 1,900 square miles (492,097 ha) of coastal

wetlands, including barrier resources, since the 1930's (Dunbar et al. 1992; Barras

et al. 1994; Barras et al. 2003). Approximately 10 percent of Louisianas remaining

coastal wetlands, including barrier islands, would be lost at a rate of approximately

6,600 acres per year (2,672 ha per year) over the next 50 years, resulting in an

additional net loss of 328,000 acres (132,794 ha) by 2050 (Barras et al. 2003).

Approximately 3,220 acres, almost the entire Terrebonne barrier islands system,

projected to be lost by 2062. The projected loss of the Terrebonne barrier islands, in

synergistic combination with the loss of other barrier island losses, would alter the

salinity regimes within the back bay estuarine systems converting them to more

marine-open water systems and resulting in the concomitant loss of various plant

and animals that utilize not only transitional barrier island habitats but also the

estuarine habitats.

The LCA Study (USACE, 2004) estimated coastal Louisiana would continue to lose

land at a rate of approximately 6,600 acres per year over the next 50 years. The

projected loss of the Terrebonne Basin barrier island system and the conversion and

loss of estuarine habitats would be in addition to the projected loss of similar

resources throughout coastal Louisiana. These impacts would be offset, to some

degree by other Federal, State, and local coastal barrier restoration efforts.

5.3.2.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.3.2.2.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

5 (NER Plan) on salinity would be negligible, if at all.

5.3.2.2.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 5 (NER Plan) would restore a net total of 2,781 acres on Raccoon,

Whiskey, Trinity and Timbalier Islands restoring these barrier islands to their

minimal geormorphological form and ecological functions. Implementing

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Alternative 5 (NER Plan) would maintain the important geomorphic boundary

between the higher salinity waters from the Gulf of Mexico and the less saline

Terrebonne estuarine system thereby preventing the conversion of the barrier

system and the interior estuarine systems to open marine habitats and contribute

to maintaining the estuarine salinity gradients. Restoration of these four islands

would also, consistent with Stone (2005), absorb wave energy during storms and

fair-weather conditions, thereby providing some storm surge protection for the

interior estuarine marshes within the basin, which would decrease land loss erosion

rates to some unknown extent.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.3.2.2.3 Cumulative

Cumulative impacts to salinity would be the synergistic effects of implementing

Alternative 5 (NER Plan), restoring a net total of 2,781 acres on four of the

Terrebonne Basin barrier islands thereby maintaining the geomorphic boundary

between the higher salinity waters from the Gulf of Mexico and the less saline

Terrebonne estuarine system. This action, in synergistic combination with other

Federal, State and local barrier island restoration actions, would prevent the

conversion of the barrier systems and the interior estuarine systems to open marine

habitats and contribute to maintaining estuarine salinity gradients. Restoring

Louisianas coastal barrier islands have been addressed, to some degree, by efforts

under the CWPPRA program, and the beneficial use of dredged material

requirements under Section 307 of the Coastal Zone Management Act of 1972,

16 U.S.C. 1451 et. seq.

5.3.2.3 Alternative 11: Whiskey (Plan C)

5.3.2.3.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

11 on salinity would be negligible, if at all.

5.3.2.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan), including restoring a net total of 527 acres

of Whiskey Island to its minimal geormorphological form and ecological functions

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over the 50-year period of analysis thereby preventing the conversion of a portion of

the Terrebonne barrier system and the interior estuarine systems to open marine

habitats as well as contributing to maintaining the estuarine salinity gradients.

5.3.2.3.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres on Whiskey Island to its

minimal geormorphological form and ecological functions with the additive

combination of impacts and benefits for overall net acres of barrier islands created,

nourished, restored, and/or protected by other Federal, State, local, and private

restoration efforts. Coastal barrier land loss in Louisiana has been addressed, to

some degree, by efforts under the Coastal Wetlands Planning, Protection and

Restoration Act (CWPPRA) program, and the beneficial use of dredged material

requirements under Section 307 of the Coastal Zone Management Act of 1972,

16 U.S.C. 1451 et. seq.

5.3.2.4 Alternative 2: Timbalier (Plan E)

5.3.2.4.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

2 on salinity would be negligible, if at all.

5.3.2.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan), including restoring a net total of 1,324

acres of Timbalier Island to its minimal geormorphological form and ecological

functions over the 50-year period of analysis thereby preventing the conversion of a

portion of the Terrebonne barrier system and the interior estuarine systems to open

marine habitats as well as contributing to maintaining the estuarine salinity

gradients.

5.3.2.4.3 Cumulative

Cumulative impacts would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 (recommended component of construction) restoring a net

total of 1,324 acres on Timbalier Island to its minimal geormorphological form and

ecological functions with the additive combination of impacts and benefits for

overall net acres of barrier islands created, nourished, restored, and/or protected by

other Federal, State, local, and private restoration efforts. Coastal barrier land loss

in Louisiana has been addressed, to some degree, by efforts under the Coastal

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Wetlands Planning, Protection and Restoration Act (CWPPRA) program, and the

beneficial use of dredged material requirements under Section 307 of the Coastal

Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.3.2.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.3.2.5.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

3 on salinity would be negligible, if at all.

5.3.2.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan), including restoring a net total of

1,851 acres of Whiskey and Timbalier Islands to their minimal geormorphological

forms and ecological functions over the 50-year period of analysis thereby

preventing the conversion of a portion of the Terrebonne barrier system and the

interior estuarine systems to open marine habitats as well as contributing to

maintaining the estuarine salinity gradients.

5.3.2.5.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 3 restoring a net total of 1,851 acres on Whiskey and

Timbalier Islands to their minimal geormorphological forms and ecological

functions with the additive combination of impacts and benefits for overall net acres

of barrier islands created, nourished, restored, and/or protected by other Federal,

State, local, and private restoration efforts. Coastal barrier land loss in Louisiana

has been addressed, to some degree, by efforts under the Coastal Wetlands

Planning, Protection and Restoration Act (CWPPRA) program, and the beneficial

use of dredged material requirements under Section 307 of the Coastal Zone

Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.3.2.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.3.2.6.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

4 on salinity would be negligible, if at all.

5.3.2.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan), including restoring a net total of

2,140 acres of Whiskey, Trinity and Timbalier Islands to their minimal

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geormorphological forms and ecological functions over the 50-year period of analysis

thereby preventing the conversion of a portion of the Terrebonne barrier system and

the interior estuarine systems to open marine habitats as well as contributing to

maintaining the estuarine salinity gradients.

5.3.2.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 3 restoring a net total of 2,140 acres on Whiskey, Trinity and

Timbalier Islands to their minimal geormorphological forms and ecological

functions with the additive combination of impacts and benefits for overall net acres

of barrier islands created, nourished, restored, and/or protected by other Federal,

State, local, and private restoration efforts. Coastal barrier land loss in Louisiana

has been addressed, to some degree, by efforts under the Coastal Wetlands

Planning, Protection and Restoration Act (CWPPRA) program, and the beneficial

use of dredged material requirements under Section 307 of the Coastal Zone

Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.4 AIR QUALITY

5.4.1.1 No action Alternative (Future without Project Conditions)

5.4.1.1.1 Direct

The No Action Alternative, not implementing Terrebonne Basin barrier island

restoration, would have no direct impacts on air quality. Existing conditions would

persist. The institutional recognition of air quality would likely continue with

additional regulations.

5.4.1.1.2 Indirect

Without any action, air quality throughout the coastal Louisiana area, including the

Study Area, would likely continue to decline into the future. The EPA (2009)

recently assessed the impacts of global change on regional US air quality. This

report points out the challenges of understanding global to regional climate and air

quality modeling because of the large number of physical, chemical, and biological

processes involved, many of which are poorly understood, all interacting in complex

ways. Reasons for the predicted air quality decline include: continued human

population growth throughout the general coastal area, further commercialization

and industrialization (e.g., oil and gas operations), increased numbers of motor

vehicles, and increased emissions from various engines.

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These indirect impacts would be coupled with the continued loss of coastal wetland

vegetation that would no longer be available to remove gaseous pollutants. There

would likely be associated increases in respiratory aliments (such as asthma) in the

human populations. Air pollution would also have adverse aesthetic impacts on

coastal viewscapes. These impacts would probably also have some impacts on the

respiratory health of humans and potentially terrestrial wildlife, but information on

such impacts is not readily available.

5.4.1.1.3 Cumulative

Continued institutional recognition of air quality, along with the continued

deterioration of air quality throughout the nation and region would likely continue

to occur. Approximately 10 percent of Louisianas remaining coastal wetlands,

including barrier islands, would be lost at a rate of approximately 6,600 acres per

year over the next 50 years, resulting in an additional net loss of 328,000 acres by

2050 (Barras et al. 2003). Approximately 3,220 acres, almost the entire Terrebonne

barrier islands system, is projected to be lost by 2062. The projected losses of the

Terrebonne barrier islands, in synergistic combination with the loss of other barrier

island losses, would contribute, to some unknown extent (EPA 2009), to altering air

quality. However, these impacts to air quality would be offset, to some degree by

other Federal, State and local wetland and barrier restoration projects.

5.4.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.4.1.2.1 Direct

Compared to the No Action Alternative, Direct impacts to ambient air quality,

resulting primarily from implementing Alternative 5 (NER Plan) would be

primarily related to emissions of construction equipment within the Study Area.

Impacts would be temporary and localized, with air quality returning to preconstruction conditions shortly after completion of construction activities. The

Study Area is located within Terrebonne Parish which is presently in attainment

for air quality. An air applicability determination analysis was performed based

upon direct and indirect emissions for estimated construction hours. Generally,

since no other indirect Federal action, such as licensing or subsequent actions would

be required or related to the restoration construction actions, any indirect

emissions, if they would occur, would be negligible. Consideration of total emissions

for each work item separately would not exceed the threshold limit applicable to

volatile organic compounds (VOCs) or nitrous oxid (NOx). Such emissions would be

classified as de minimus and no further action would be required.

5.4.1.2.2 Indirect

Over the 50-year period of analysis Alternative 5 (NER Plan) would restore a net

total of 1,459 acres of vegetated barrier habitats that would help to improve local

air quality by reducing particulates and gaseous air pollutants. It is reasonable to

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extrapolate from the findings of researchers such as David J. Nowak (personal

communication, David J. Nowak, Project Leader, USDA Forest Service,

Northeastern Research Station, 5 Moon Library, SUNY-CESF, Syracuse, New York)

that the trees and vegetation in coastal Louisiana would improve air quality.

Improvement of air quality would provide positive benefits for humans overall,

although this relative difference would likely be minimal because of the size of the

Study Area and distance from human population centers.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.4.1.2.3 Cumulative

Cumulative impacts to air quality bottoms would be the synergistic effect of

implementing Alternative 5 (NER Plan), with restoration of a net total of 1,459

acres of vegetated barrier habitats, along with the synergistic combination of

impacts and benefits for overall net acres of vegetated barrier resources created,

nourished, restored, and/or protected by other Federal, State, local, and private

restoration efforts. Coastal barrier island restoration in Louisiana has been

addressed, to some degree, by efforts under the CWPPRA program, and the

beneficial use of dredged material requirements under Section 307 of the Coastal

Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.impacts and benefits of

existing wetlands being converted.

5.4.1.3 Alternative 11: Whiskey (Plan C)

5.4.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to ambient air quality of

implementing alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan), although to a much lesser extent.

5.4.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER) with restoration of a net total of 311 acres of

vegetated barrier habitats that would help to improve local air quality by reducing

particulates and gaseous air pollutants.

5.4.1.3.3 Cumulative

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Cumulative impacts of implementing Alternative 11 would be similar to those

described for the Whiskey Island component of Alternative 5 (NER Plan) with

restoration of a net total of 311 acres of vegetated barrier habitats, along with the

synergistic combination of impacts and benefits for overall net acres of vegetated

barrier resources created, nourished, restored, and/or protected by other Federal,

State, local, and private restoration efforts.

5.4.1.4 Alternative 2: Timbalier (Plan E)

5.4.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to ambient air quality of

implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan), although to a much lesser extent.

5.4.1.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Whiskey Island component

of Alternative 5 (NER Plan) with restoration of a net total of 706 acres of vegetated

barrier habitats that would help to improve local air quality by reducing

particulates and gaseous air pollutants.

5.4.1.4.3 Cumulative

Cumulative impacts of implementing Alternative 2 would be similar to those

described for the Timbalier Island component of Alternative 5 (NER Plan) with

restoration of a net total of 706 acres of vegetated barrier habitats, along with the

synergistic combination of impacts and benefits for overall net acres of vegetated

barrier resources created, nourished, restored, and/or protected by other Federal,

State, local, and private restoration efforts).

5.4.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.4.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to ambient air quality of

implementing Alternative 3 would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan), although to a much

lesser extent.

5.4.1.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) with restoration of a net total of

1,017 acres of vegetated barrier habitats that would help to improve local air

quality by reducing particulates and gaseous air pollutants.

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5.4.1.5.3 Cumulative

Cumulative impacts of implementing Alternative 3 would be similar to those

described for the Whiskey and Timbalier Islands components of Alternative 5 (NER

Plan) with restoration of a net total of 1,017 acres of vegetated barrier habitats,

along with the synergistic combination of impacts and benefits for overall net acres

of vegetated barrier resources created, nourished, restored, and/or protected by

other Federal, State, local, and private restoration efforts.

5.4.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.4.1.6.1 Direct

Compared to the No Action Alternative, direct impacts to ambient air quality of

implementing Alternative 4 would be similar to those described for the Whiskey,

Trinity and Timbalier Islands components of Alternative 5 (NER Plan), although to

a much lesser extent.

5.4.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) with restoration of a net

total of 1,120 acres of vegetated barrier habitats that would help to improve local

air quality by reducing particulates and gaseous air pollutants.

5.4.1.6.3 Cumulative

Cumulative impacts of implementing Alternative 3 would be similar to those

described for the Whiskey, Trinity and Timbalier Islands components of Alternative

5 (NER Plan) with restoration of a net total of 1,120 acres of vegetated barrier

habitats, along with the synergistic combination of impacts and benefits for overall

net acres of vegetated barrier resources created, nourished, restored, and/or

protected by other Federal, State, local, and private restoration efforts.

5.5 NOISE

5.5.1.1 No Action Alternative (Future without Project Conditions

5.5.1.1.1 Direct

The No Action Alternative, not implementing the barrier island restoration

features, would have no direct impact on noise. Existing conditions would persist.

Institutional recognition of noise, such as provided by the regulations for

Occupational Noise Exposure (29 CFR Part 1910.95) under the Occupational Safety

and Health Act of 1970, as amended, would continue. Localized and temporary

noise impacts, such as commercial and recreational fishing boats and oil and gas

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exploration activities, would likely continue to affect fish, wildlife and those humans

that utilize the Study Area.

5.5.1.1.2 Indirect

There would be no indirect impacts of the No-Action Alternative on noise. Not

implementing the barrier island restoration features would result in the persistence

of existing conditions. The Study Area consists of remote and uninhabited barrier

islands.

5.5.1.1.3 Cumulative

There would be no cumulative impacts of the No-Action Alternative on noise. Not

implementing the barrier island restoration features would result in the persistence

of existing conditions. The Study Area consists of remote and uninhabited barrier

islands. The noise from nearby urban areas has little, if any, impact on the Study

Area. This is expected to continue in the future.

5.5.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.5.1.2.1 Direct

Compared to the No Action Alternative, construction activities associated with

implementing Alternative 5 (NER Plan) would result in temporary and localized

increases to noise levels in the Study Area. Potential noise impacts concerns would

be expected from construction activities, although construction equipment is limited

in the level of noise that can be emitted. Institutional recognition of noise, such as

provided by the regulations for Occupational Noise Exposure (29 CFR Part 1910.95)

under the Occupational Safety and Health Act of 1970, as amended, would continue.

The Occupational Noise Exposure regulation mandate that noise levels emitted

from construction equipment be below 90 dB for exposures of eight hours per day or

more.

During the 2,480 day long construction period (mobilization/demobilization not

included), localized and temporary noise impacts would likely result in wildlife and

fishery resources temporarily displaced from the Study Area during construction

activities. In some instances, noise impacts may directly impact fish and wildlife

species. These organisms would generally avoid the construction area. However,

tolerance of unnatural disturbance varies among wildlife. Therefore coordination

with the USFWS in identifying the key species of concern and following feasible

administrative and or engineering controls, determining and implementing

appropriate buffer zones, and implementing construction activity windows, would

be implemented to address these issues.

5.5.1.2.2 Indirect

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Compared to the No Action Alternative, there are no anticipated long-term

significant adverse indirect noise impacts of implementing Alternative 5 (NER

Plan). Any project-related noise impacts are expected to be localized, temporary,

and minor in nature.

5.5.1.2.3 Cumulative

Compared to the No Action Alternative, cumulative noise impacts of implementing

Alternative 5 (NER Plan) would be localized and short-term causing local fish and

wildlife populations to relocate during construction. Long-term adverse cumulative

impacts due to noise levels would not be expected with implementation of

Alternative 5 (NER Plan) when considered in combination with impacts and

benefits of other Federal, State, local, and private restoration efforts.

5.5.1.3 Alternative 11: Whiskey (Plan C)

5.5.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to noise associated with

implementing Alternative 11 would be similar to the Whiskey Island component of

Alternative 5 (NER Plan) ) resulting in temporary and localized increases to noise

levels in the Study Area during construction. Once construction activities are

completed, noise levels would return to pre-construction conditions.

5.5.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts to noise of implementing

Alternative 11 would be similar to the Whiskey Island component of Alternative 5

(NER Plan). There are no anticipated long-term significant adverse indirect noise

impacts of implementing Alternative 11 (recommended component of construction).

Any project-related noise impacts are expected to be localized, temporary, and

minor in nature.

5.5.1.3.3 Cumulative

Compared to the No Action Alternative, incremental cumulative impacts to noise

from implementing Alternative 11 would be similar to the Whiskey Island

component of Alternative 5 (NER Plan). There are no anticipated long-term

significant adverse cumulative noise impacts of implementing Alternative 11. Longterm adverse cumulative impacts due to noise would not be expected with

implementation of Alternative 11 when considered in combination with impacts and

benefits of other Federal, State, local, and private restoration efforts.

5.5.1.4 Alternative 2: Timbalier (Plan E)

5.5.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to noise associated with

implementing Alternative 2 (recommended component of construction) would be

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similar to the Timbalier Island component of Alternative 5 (NER Plan) resulting in

temporary and localized increases to noise levels in the Study Area during

construction. Once construction activities are completed, noise levels would return

to pre-construction conditions.

5.5.1.4.2 Indirect

Compared to the No Action Alternative, indirect impacts to noise of implementing

Alternative 2 would be similar to the Timbalier Island component of Alternative 5

(NER Plan). There are no anticipated long-term significant adverse indirect noise

impacts of implementing Alternative 2. Any project-related noise impacts are

expected to be localized, temporary, and minor in nature.

5.5.1.4.3 Cumulative

Compared to the No Action Alternative, incremental cumulative impacts to noise

from implementing Alternative 2 would be similar to the Timbalier Island

component of Alternative 5 (NER Plan). There are no anticipated long-term

significant adverse cumulative noise impacts of implementing Alternative 2. Longterm adverse cumulative impacts due to noise would not be expected with

implementation of Alternative 2 when considered in combination with impacts and

benefits of other Federal, State, local, and private restoration efforts.

5.5.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.5.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to noise associated with

implementing Alternative 3 (recommended component of construction) would be

similar to the Whiskey and Timbalier Islands components of Alternative 5 (NER

Plan) resulting in temporary and localized increases to noise levels in the Study

Area during construction. Once construction activities are completed, noise levels

would return to pre-construction conditions.

5.5.1.5.2 Indirect

Compared to the No Action Alternative, indirect impacts to noise of implementing

Alternative 3 would be similar to the Whiskey and Timbalier Islands components of

Alternative 5 (NER Plan). There are no anticipated long-term significant adverse

indirect noise impacts of implementing Alternative 3. Any project-related noise

impacts are expected to be localized, temporary, and minor in nature.

5.5.1.5.3 Cumulative

Compared to the No Action Alternative, incremental cumulative impacts to noise

from implementing Alternative 3 would be similar to the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan). There are no anticipated longterm significant adverse cumulative noise impacts of implementing Alternative 3.

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Long-term adverse cumulative impacts due to noise would not be expected with

implementation of Alternative 3 when considered in combination with impacts and

benefits of other Federal, State, local, and private restoration efforts.

5.5.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.5.1.6.1 Direct

Compared to the No Action Alternative, direct impacts to noise associated with

implementing Alternative 4 (recommended component of construction) would be

similar to the Whiskey, Trinity and Timbalier Islands components of Alternative 5

(NER Plan) resulting in temporary and localized increases to noise levels in the

Study Area during construction. Once construction activities are completed, noise

levels would return to pre-construction conditions.

5.5.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts to noise of implementing

Alternative 4 would be similar to the Whiskey, Trinity and Timbalier Islands

components of Alternative 5 (NER Plan). There are no anticipated long-term

significant adverse indirect noise impacts of implementing Alternative 4. Any

project-related noise impacts are expected to be localized, temporary, and minor in

nature.

5.5.1.6.3 Cumulative

Compared to the No Action Alternative, incremental cumulative impacts to noise

from implementing Alternative 4 would be similar to the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan). There are no

anticipated long-term significant adverse cumulative noise impacts of implementing

Alternative 4. Long-term adverse cumulative impacts due to noise would not be

expected with implementation of Alternative 4 when considered in combination

with impacts and benefits of other Federal, State, local, and private restoration

efforts.

5.6 VEGETATION RESOURCES

5.6.1 Riparian Vegetation Resources

5.6.1.1 No Action Alternative (Future without Project Conditions)

5.6.1.1.1 Direct

The No Action Alternative, not implementing the Terrebonne Basin barrier islands

restoration project, would have no direct impacts to riparian vegetation as no such

resources are present on the barrier islands. However, existing conditions, including

the continued loss of riparian vegetation resources within the adjacent Terrebonne

Basin estuarine system would persist.

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5.6.1.1.2 Indirect

There are no existing riparian vegetation resources on the Terrebonne Basin barrier

islands. Hence, without any action there would be no indirect impacts on the

Terrebonne Basin barrier islands to riparian vegetation resources.

Without any action, approximately 3,220 acres of existing barrier resources from

the seven island Terrebonne Basin barrier system (East Timbalier, Timbalier,

Trinity, East Island, Wine, Whiskey and Raccoon Island) would likely continue to

degrade, fragment and eventually convert into shallow open water bottoms over the

50-year period of analysis. The loss of the Terrebonne Basin barrier island system

would consequently result in higher wave energy levels and associated shoreline

erosion in the adjacent estuarine bays (Stone and McBride 1998, Stone et al 2003,

and Stone et al. 2005). Some unknown portions of the adjacent estuarine systems,

along with their riparian vegetation resources, would be transformed into open

water habitat.

The loss of estuarine riparian vegetation resources would result in adverse impacts

to important transitional habitat between estuarine and terrestrial environments

as well as unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting

habitats). The degradation and eventual loss of estuarine riparian vegetation

resources would also result in the loss of important wildlife habitat which would

likely increase competition between and within various wildlife species for

diminishing habitat resources. The loss of estuarine riparian vegetated habitat

would also result in a loss in primary productivity, as well as undetermined impacts

to recreation, aesthetic and associated socioeconomic resources.

5.6.1.1.3 Cumulative

The incremental cumulative impacts of the No Action Alternative would be the

conversion of some unknown acreage of estuarine riparian vegetation resources due

to the higher wave energy levels and associated shoreline erosion (Stone and

McBride 1998, Stone et al 2003, and Stone et al. 2005) resulting from the loss of the

Terrebonne Basin barrier island system and other coastal Louisiana barrier

systems.

These impacts would be offset, to some degree, by the synergistic additive

combination of impacts and benefits of coastal barrier island restoration by other

Federal, State, local, and private restoration efforts that would protect adjacent

estuarine systems, and their associated riparian vegetation resources, from

converting to shallow open water habitats. Coastal barrier islands in Louisiana

have been restored, to some degree, by efforts under the CWPPRA program, and the

beneficial use of dredged material requirements under Section 307 of the Coastal

Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

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5.6.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.6.1.2.1 Direct

There would be no direct impacts to riparian wetland vegetation as no such

resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 5 (NER Plan) would be similar to the No

Action Alternative.

5.6.1.2.2 Indirect

There would be no indirect impacts of implementing Alternative 5 (NER Plan) on

the Terrebonne Basin barrier islands as there are no riparian vegetation resources

on the barrier islands.

However, compared to the No Action Alternative, implementing Alternative 5 (NER

Plan) would restore a net total of 2,781 acres on Raccoon, Timbalier, Trinity, and

Whiskey Islands. Restoring these barrier islands to their minimal

geormorphological form would result, consistent with Stone and McBride (1998),

Stone et al. (2003) and Stone et al. (2005), in the restored barrier islands absorbing

wave energy during storms and fair-weather conditions and providing some storm

surge protection. Restoring the Terrebonne Basin barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the estuarine system, especially riparian vegetation resources, to open

water habitat.

Implementing Alternative 5 (NER Plan) would restoring four of the seven

Terrebonne barrier islands to their minimal geormorphological form thereby

reducing, to some undetermined level, the loss of adjacent estuarine riparian

vegetation resources. This action would prevent/reduce the conversion of some

unknown portion of the existing back bay estuarine system and its riparian

vegetation resources into more open water system.

The estuarine riparian vegetation resources would, in turn, provide important

transitional habitat between estuarine and terrestrial environments as well as

unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting habitats). In

addition, preventing/reducing the loss of estuarine riparian vegetation resources

would provide important wildlife habitat which would likely decrease competition

between and within various wildlife species for diminishing habitat resources. The

prevention/reduction of loss of riparian vegetated habitat would also result in an

undetermined increase in primary productivity compared to the No Action

Alternative.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

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loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.6.1.2.3 Cumulative

Cumulative impacts would be the incremental impacts to riparian vegetation

resources from implementing Alternative 5 (NER Plan) when added to all past,

present and reasonably foreseeable barrier restoration efforts. Alternative 5 (NER

Plan) would restore the geomorphologic form and ecological function to a net total of

2,781 acres of Terrebonne barrier island resources. Restoration of the

geomorphologic form to Raccoon, Whiskey, Trinity and Timbalier Islands would,

consistent with Stone (2005), enable these barrier islands to maintain their

ecological function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne interior estuarine marshes and

associated riparian vegetation resources. These incremental impacts would be in

addition to similar impacts for other barrier island restoration efforts across the

Louisiana coastal area by other Federal, State, and local barrier island restoration

efforts.

5.6.1.3 Alternative 11: Whiskey (Plan C)

5.6.1.3.1 Direct

There would be no direct impacts to riparian wetland vegetation as no such

resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 11 would be similar to the No Action

Alternative.

5.6.1.3.2 Indirect

There would be no indirect impacts of implementing Alternative 11 on the

Terrebonne Basin barrier islands as there are no riparian vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to riparian vegetation

resources of implementing Alternative 11 would be similar to those described for

the Whiskey Island component of Alternative 5 (NER) but to a lesser degree.

Alternative 11 would restore a net total of 527 acres thereby restoring Whiskey

Island to its geomorphologic form which would contribute to its ecological function

of preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially riparian vegetation resources, to open water habitat.

5.6.1.3.3 Cumulative

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These incremental impacts would be in addition to similar impacts for other barrier

island restoration efforts across the Louisiana coastal area by other Federal, State,

and local barrier island restoration efforts.

Cumulative impacts would be the incremental impacts to riparian vegetation

resources from implementing Alternative 11 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 11 would restore the

geomorphologic form and ecological function to a net total of 527 acres on Whiskey

Island. Restoration of the geomorphologic form to Whiskey Island would, consistent

with Stone (2005), enable this barrier island to maintain its function of absorbing

wave energy during storms and fair-weather conditions and provide some

undetermined level of storm surge protection and reduction of wave potential for

the Terrebonne interior estuarine marshes and associated riparian vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.6.1.4 Alternative 2: Timbalier (Plan E)

5.6.1.4.1 Direct

There would be no direct impacts to riparian wetland vegetation as no such

resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 2 would be similar to the No Action

Alternative.

5.6.1.4.2 Indirect

There would be no indirect impacts of implementing Alternative 2 on the

Terrebonne Basin barrier islands as there are no riparian vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to riparian vegetation

resources of implementing Alternative 2 would be similar to those described for the

Whiskey Island component of Alternative 5 (NER Plan) but to a lesser degree.

Alternative 2 would restore a net total of 1,324 acres thereby restoring Timbalier

Island to its geomorphologic form which would contribute to its ecological function

of preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially riparian vegetation resources, to open water habitat.

5.6.1.4.3 Cumulative

Cumulative impacts would be the incremental impacts to riparian vegetation

resources from implementing Alternative 2 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 2 would restore the

geomorphologic form and ecological function to a net total of 1,324 acres on

Timbalier Island. Restoration of the geomorphologic form to Timbalier Island

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would, consistent with Stone (2005), enable this barrier island to maintain its

function of absorbing wave energy during storms and fair-weather conditions and

provide some undetermined level of storm surge protection and reduction of wave

potential for the Terrebonne interior estuarine marshes and associated riparian

vegetation resources. These incremental impacts would be in addition to similar

impacts for other barrier island restoration efforts across the Louisiana coastal area

by other Federal, State, and local barrier island restoration efforts.

5.6.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.6.1.5.1 Direct

There would be no direct impacts to riparian wetland vegetation as no such

resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 3 would be similar to the No Action

Alternative.

5.6.1.5.2 Indirect

There would be no indirect impacts of implementing Alternative 3 on the

Terrebonne Basin barrier islands as there are no riparian vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to riparian vegetation

resources of implementing Alternative 3 would be similar to those described for the

Whiskey and Timbalier Islands components of Alternative 5 (NER Plan) but to a

lesser degree. Alternative 3 would restore a net total of 1,851 acres thereby

restoring Whiskey and Timbalier Islands to their geomorphologic forms which

would contribute to their ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine system, especially riparian vegetation

resources, to open water habitat.

5.6.1.5.3 Cumulative

Cumulative impacts would be the incremental impacts to riparian vegetation

resources from implementing Alternative 3 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 3 would restore the

geomorphologic form and ecological function to a net total of 1,851 acres on Whiskey

and Timbalier Islands. Restoration of the geomorphologic form to Whiskey and

Timbalier Islands would, consistent with Stone (2005), enable these barrier islands

to maintain their function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne interior estuarine marshes and

associated riparian vegetation resources. These incremental impacts would be in

addition to similar impacts for other barrier island restoration efforts across the

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Louisiana coastal area by other Federal, State, and local barrier island restoration

efforts.

5.6.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.6.1.6.1 Direct

There would be no direct impacts to riparian wetland vegetation as no such

resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 4 would be similar to the No Action

Alternative.

5.6.1.6.2 Indirect

There would be no indirect impacts of implementing Alternative 4 on the

Terrebonne Basin barrier islands as there are no riparian vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to riparian vegetation

resources of implementing Alternative 4 would be similar to those described for the

Whiskey, Trinity and Timbalier Islands components of Alternative 4 but to a lesser

degree. Alternative 4 would restore a net total of 2,140 acres thereby restoring

Whiskey, Trinity and Timbalier Islands to their geomorphologic forms which would

contribute to their ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine system, especially riparian vegetation resources, to

open water habitat.

5.6.1.6.3 Cumulative

Cumulative impacts would be the incremental impacts to riparian vegetation

resources from implementing Alternative 4 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 4 would restore the

geomorphologic form and ecological function to a net total of 2,140 acres on

Whiskey, Trinity and Timbalier Islands. Restoration of the geomorphologic form to

Whiskey, Trinity and Timbalier Islands would, consistent with Stone (2005), enable

these barrier islands to maintain their function of absorbing wave energy during

storms and fair-weather conditions and provide some undetermined level of storm

surge protection and reduction of wave potential for the Terrebonne interior

estuarine marshes and associated riparian vegetation resources. These incremental

impacts would be in addition to similar impacts for other barrier island restoration

efforts across the Louisiana coastal area by other Federal, State, and local barrier

island restoration efforts.

5.6.2 Wetland Vegetation Resources

5.6.2.1 No Action Alternative (Future without Project Conditions)

5.6.2.1.1 Direct

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The No Action Alternative, not implementing the Terrebonne Basin barrier islands

restoration project, would have no direct impacts on existing barrier island wetland

vegetation resources or on adjacent Terrebonne Basin estuarine wetland vegetation

resources. Existing conditions, the continued loss of barrier island wetland

vegetation (beach, dune and marsh) and Terrebonne Basin estuarine wetland

vegetation resources, would persist.

5.6.2.1.2 Indirect

Without any action, wetland vegetation resources from the seven island Terrebonne

Basin barrier system and the adjacent Terrebonne Basin estuarine system would

likely continue to degrade, fragment and eventually convert into shallow open water

bottom habitat over the 50-year period of analysis.

The No Action Alternative would result in the conversion of 3,220 acres of existing

Terrebonne Basin barrier island beach, dune and marsh wetland vegetation

habitats to open water bottom habitat over the 50-year period of analysis. The loss

of the Terrebonne Basin barrier island system would consequently result in higher

wave energy levels and associated shoreline erosion in the adjacent estuarine bays

(Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005). Some unknown

portions of the adjacent estuarine systems, along with their wetland vegetation

resources, would be transformed into open water habitat.

The trend in barrier island loss is characterized by simultaneous reduction of total

area and elevation resulting in a reduction in the size and diversity of vegetation

zones, to varying degrees, across all of the barrier islands. Continued degradation

and loss, combined with loss of replenishing processes, has also accelerated decline

in the interdependent processes of plant production and vertical maintenance

necessary for a stable barrier island ecosystem.

Conversion of existing barrier and estuarine wetland vegetation habitats would

include degradation and loss of important and essential fish and wildlife habitats

used for shelter, nesting, feeding, roosting, cover, nursery, and other life

requirements; reduction in productivity; degradation and loss of EFH, especially

transitional habitat between estuarine and marine environments; degradation and

loss of stopover habitat for migrating neotropic birds; and increased inter- and

intra-specific competition between resident and migratory fish and wildlife species

for decreasing coastal barrier island resources, as well as undetermined impacts to

recreation, aesthetic and associated socioeconomic resources.

5.6.2.1.3 Cumulative

The incremental cumulative impacts of the No Action Alternative would be the

conversion of some unknown acreage of Terrebonne Basin barrier island wetland

vegetation resources to open water bottom habitats. In addition, there would be

undetermined impacts to adjacent Terrebonne Basin estuarine wetland vegetation

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resources due to the higher wave energy levels and associated shoreline erosion

(Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005) resulting from

Terrebonne Basin barrier island conversion to open water bottom habitat.

These impacts would be offset, to some degree, by the synergistic additive

combination of impacts and benefits of coastal barrier island restoration by other

Federal, State, local, and private restoration efforts that would restore barrier

island wetland vegetation resources that would, in turn, protect adjacent estuarine

systems and their associated wetland vegetation resources from converting to

shallow open water habitats. Coastal barrier islands in Louisiana have been

restored, to some degree, by efforts under the CWPPRA program, and the beneficial

use of dredged material requirements under Section 307 of the Coastal Zone

Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.6.2.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.6.2.2.1 Direct

Compared to the No Action Alternative, direct impacts to wetland vegetation

resources of implementing Alternative 5 (NER Plan) would primarily result from

construction activities related to placement of borrow material on existing

fragmented dune, supratidal, intertidal (gulfside and bayside) and shallow open

water habitats. The proposed action would initially restore a total of 5,840 acres on

Raccoon, Whiskey, Trinity, and Timbalier Islands. This would include initial

restoration of a total of 472 acres of dune, 4,320 acres of supratidal and 1,048 acres

of intertidal vegetated habitats.

Dune restoration for all alternatives would include installation of sand fencing and

plantings of native vegetation that would be anticipated to promote additional dune

elevation by capturing Aeolian sands. One shore parallel fence would likely be

installed about 50 ft north of the southern toe of the dune to continue the capture of

transported sand until the surface is vegetated. The sand fence would extend along

the total length of the constructed dune. Sand fences must be installed in

sequence/phases. The installation should start from the southern side of the dune

so as to build dune towards the Gulf of Mexico and proceed north. Additional rows

of sand fencing could be added once the existing sand fence is full (i.e. sand is

stacked up to the top of the fence.)

Seeding of the dune platform (aerial or ground application) would be considered

depending on the time of the year construction is completed. Rye grass seed could

be considered if construction is completed in the summer or fall to be used as a

ground cover during the winter months. Bermuda grass seed has been dispersed on

the barrier island dune platforms in the past as well, but with strong objection by

the Federal and State wildlife agencies as it is non-native.

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Dune and supratidal plants would consist of a variety of dune species including

bitter panicum (Panicum amarum var amarum Fourchon), sea oats (Uniola

paniculata Caminada), marshhay cordgrass (Spartina patens Gulf Coast) and gulf

cordgrass (Spartina spartinae). Plants shall be grown mainly in four inch

containers (sea oats in a slightly larger container). Species recommendations may

change due to soil properties and conditions, elevation after final construction,

salinity, available soil moisture, and other site conditions.

Other plants that could be considered to add diversity (depending upon availability)

include seacoast bluestem (Schizachyrium maritimum), seashore dropseed

(Sporobolous virginicus), and salt grass (Distichlis spicata). Woody species that

would be considered for planting (depending upon availability) on the dune and

supratidal swale areas include, but are not limited to matrimony vine, wax myrtle,

Iva frutescens, baccharis species, and hercules club. Plants on the dune, supratidal,

and marsh platforms would likely be installed 5-ft apart with 20-ft between rows.

However, woody vegetation would likely be planted at a density of 10-ft on center.

On Trinity Island, construction impacts to much of the existing mangrove habitat

would be avoided so that this would serve as both a seed and vegetative source.

Marsh plantings would primarily consist of smooth cordgrass (Spartina alterniflora

Vermilion). Depending upon availability, a smaller planting of black mangrove

(Avicennia germinans Pelican) may be incorporated to add a larger seed bank for

black mangroves. Plants shall mainly consist of vegetative plug material, four inch

containers, or tube-tainers (mangroves). The marsh platform planting area would

be filling broken marsh and shallow open water. Marsh plants would likely be

placed approximately 20 ft apart with plants approximately 3-ft on center.

5.6.2.2.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

alternative 5 (NER Plan) would be a net increase of 2,781 acres with 2,883 average

annual habitat units (AAHUs) of important and essential vegetated habitats used

by fish and wildlife for shelter, nesting, feeding, roosting, cover, nursery, and other

life requirements; increased vegetation growth and productivity; and reduced interand intra-specific species competition between resident and non-resident fish and

wildlife species for limited coastal vegetation. Alternative 5 (NER Plan) would

restore and rehabilitate dune, supratidal and intertidal vegetated coastal barrier

habitats; reduce conversion of these habitats to open water habitat; and provide

higher quality EFH, especially nursery habitat, for several species, including brown

and white shrimp, and blue crab. Vegetative plantings would contribute to reestablishment of a variety of wetland species that would further aid in sediment

trapping. Vegetative productivity would likely increase due to increased vegetated

acres of barrier habitats. Important stopover habitats used by migrating

neotropical birds would be restored and sustained for future use over the 50-year

period of analysis. Compared to the No Action Alternative, implementing

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Alternative 5 (NER Plan) would delay the conversion of vegetated barrier habitats

to open water habitats over the 50-year period of analysis.

In addition, compared to the No Action Alternative, implementing Alternative 5

(NER Plan) would restore Raccoon, Timbalier, Trinity, and Whiskey Islands to their

minimal geormorphological form would result, consistent with Stone and McBride

(1998), Stone et al. (2003) and Stone et al. (2005), in the restored barrier islands

absorbing wave energy during storms and fair-weather conditions and providing

some storm surge protection. Restoring these four barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the estuarine system, especially wetland vegetation resources, to open

water habitat.

Implementing Alternative 5 (NER Plan) would restoring four of the seven

Terrebonne barrier islands to their minimal geormorphological form thereby

reducing, to some undetermined level, the loss of adjacent estuarine wetland

vegetation resources. This action would prevent/reduce the conversion of some

unknown portion of the existing Terrebonne Basin estuarine system and its wetland

vegetation resources into more open water system.

The estuarine wetland vegetation resources would, in turn, provide important

transitional habitat between estuarine and terrestrial environments as well as

unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting habitats). In

addition, preventing/reducing the loss of estuarine riparian vegetation resources

would provide important wildlife habitat which would likely decrease competition

between and within various wildlife species for diminishing habitat resources. The

prevention/reduction of loss of riparian vegetated habitat would also result in an

undetermined increase in primary productivity compared to the No Action

Alternative.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.6.2.2.3 Cumulative

Cumulative impacts would be the incremental impact from implementing

Alternative 5 (NER Plan) when added to all past, present and reasonably

foreseeable similar barrier restoration efforts. Alternative 5 (NER Plan) would

restore a net total of 2,781 acres of fragmented dune, supratidal, intertidal (gulfside

and bayside) and shallow open water habitats on Raccoon (net total 641 acres),

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Whiskey (net total 527 acres), Trinity (net total 289 acres), and Timbalier Islands

(net total 1,324 acres) which would be in addition to impacts and benefits for overall

net acres of vegetated barrier resources created, nourished, restored, and/or

protected by other Federal, State, local, and private restoration efforts.

In addition, Alternative 5 (NER Plan) would restore the geomorphologic form to

Raccoon, Whiskey, Trinity and Timbalier Islands that would, consistent with Stone

(2005), enable these barrier islands to maintain their ecological function of

absorbing wave energy during storms and fair-weather conditions and provide some

undetermined level of storm surge protection and reduction of wave potential for

the Terrebonne interior estuarine marshes and associated riparian vegetation

resources. Coastal barrier land loss in Louisiana has been addressed, to some

degree, by efforts under the Coastal Wetlands Planning, Protection and Restoration

Act (CWPPRA) program, and the beneficial use of dredged material requirements

under Section 307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et.

seq.

5.6.2.3 Alternative 11: Whiskey (Plan C with renourishment)

5.6.2.3.1 Direct

Compared to the No Action Alternative, direct impact to wetland vegetation

resources of implementing Alternative 11 would be similar to those described for

the Whiskey Island component of Alternative 5 (NER Plan), including initial

restoration of a total 1,272 acres with 65 acres of dune, 830 acres of supratidal, 377

acres of intertidal vegetation resources on Whiskey Island.

5.6.2.3.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wetland vegetation

resources of implementing Alternative 11 would be similar to those described for

the Whiskey Island component of Alternative 5 (NER Plan). Alternative 11

(recommended component of construction) would restore a net total of 527 acres of

wetland vegetation resources with 0 net acres dune, 164 net acres supratidal, and

363 net acres of intertidal vegetation resources over the 50-year period of analysis.

In addition, Alternative 11 would restore Whiskey Island to its minimal

geomorphologic form which would contribute to its ecological function of preventing

conversion of the adjacent Terrebonne Basin estuarine system, especially wetland

vegetation resources, to open water habitat.

5.6.2.3.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres of barrier wetland

vegetation resources on Whiskey Island.

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Alternative 11 would also, restore the minimal geomorphologic form to Whiskey

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.6.2.4 Alternative 2: Timbalier (Plan E)

5.6.2.4.1 Direct

Compared to the No Action Alternative, direct impacts to wetland vegetation

resources of implementing Alternative 2 would be similar to those described for the

Timbalier Island component of Alternative 5 (NER Plan), including initial

restoration of a total 2,630 acres with 215 acres of dune, 2,346 acres of supratidal,

69 acres of intertidal vegetation resources on Timbalier Island.

5.6.2.4.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wetland vegetation

resources of implementing Alternative 2 would be similar to those described for the

Timbalier Island component of Alternative 5 (NER Plan). Alternative 2 would

restore a net total of 1,324 acres of wetland vegetation resources with 0 net acres

dune, 164 net acres supratidal, and 363 net acres of intertidal wetland vegetation

resources over the 50-year period of analysis. In addition, Alternative 11 would

restore Timbalier Island to its minimal geomorphologic form which would

contribute to its ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine system, especially wetland vegetation resources, to

open water habitat.

5.6.2.4.3 Cumulative

Cumulative impacts would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 restoring a net total of 1,324 acres of barrier wetland

vegetation resources on Timbalier Island.

Alternative 2 would also restore the minimal geomorphologic form to Timbalier Island that

would, consistent with Stone (2005), enable this barrier island to maintain its ecological function

of absorbing wave energy during storms and fair-weather conditions and provide some

undetermined level of storm surge protection and reduction of wave potential for the Terrebonne

Basin estuarine wetland vegetation resources. These incremental impacts would be in addition to

similar impacts for other barrier island restoration efforts across the Louisiana coastal area by

other Federal, State, and local barrier island restoration efforts.

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5.6.2.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.6.2.5.1 Direct

Compared to the No Action Alternative, direct impacts to wetland vegetation

resources of implementing Alternative 3 would be similar to those described for the

Whiskey and Timbalier Islands component of Alternative 5 (NER Plan), including

initial restoration of a total 3,902 acres with 280 acres of dune, 3,176 acres of

supratidal, 446 acres of intertidal vegetation resources on Whiskey and Timbalier

Islands.

5.6.2.5.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wetland vegetation

resources of implementing Alternative 3 would be similar to those described for the

Whiskey and Timbalier Islands components of Alternative 5 (NER Plan).

Alternative 3 would restore a net total of 1,851 acres of wetland vegetation

resources with 0 net acres dune, 400 net acres supratidal, and 1,451 net acres of

intertidal wetland vegetation resources over the 50-year period of analysis. In

addition, Alternative 3 would restore Whiskey and Timbalier Islands to their

minimal geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially wetland vegetation resources, to open water habitat.

5.6.2.5.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan) including the synergistic

interaction of the impacts of Alternative 3 restoring a net total of 1,851 acres of

barrier wetland vegetation resources on Whiskey and Timbalier Islands.

Alternative 3 would also restore the minimal geomorphologic form to Whiskey and

Timbalier Islands that would, consistent with Stone (2005), enable these barrier

islands to maintain their ecological function of absorbing wave energy during

storms and fair-weather conditions and provide some undetermined level of storm

surge protection and reduction of wave potential for the Terrebonne Basin estuarine

wetland vegetation resources. These incremental impacts would be in addition to

similar impacts for other barrier island restoration efforts across the Louisiana

coastal area by other Federal, State, and local barrier island restoration efforts.

5.6.2.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.6.2.6.1 Direct

Compared to the No Action Alternative, direct impacts to wetland vegetation

resources of implementing Alternative 4 would be similar to those described for the

Whiskey, Trinity and Timbalier Islands component of Alternative 5 (NER Plan),

including initial restoration of a total 5,051 acres with 409 acres of dune, 3,632

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acres of supratidal, 1,010 acres of intertidal vegetation resources on Whiskey,

Trinity and Timbalier Islands.

5.6.2.6.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wetland vegetation

resources of implementing Alternative 4 would be similar to those described for the

Whiskey, Trinity and Timbalier Islands components of Alternative 5 (NER Plan).

Alternative 4 would restore a net total of 2,140 acres of wetland vegetation

resources with 0 net acres dune, 490 net acres supratidal, and 1,650 net acres of

intertidal wetland vegetation resources over the 50-year period of analysis. In

addition, Alternative 4 would restore Whiskey, Trinity and Timbalier Islands to

their minimal geomorphologic form which would contribute to their ecological

function of preventing conversion of the adjacent Terrebonne Basin estuarine

system, especially wetland vegetation resources, to open water habitat.

5.6.2.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey, Trinity

and Timbalier Islands components of Alternative 5 (NER Plan) including the

synergistic interaction of the impacts of Alternative 4 restoring a net total of 2,140

acres of barrier wetland vegetation resources on Whiskey, Trinity and Timbalier

Islands.

Alternative 4 would also restore the minimal geomorphologic form to Whiskey,

Trinity and Timbalier Islands that would, consistent with Stone (2005), enable

these barrier islands to maintain their ecological function of absorbing wave energy

during storms and fair-weather conditions and provide some undetermined level of

storm surge protection and reduction of wave potential for the Terrebonne Basin

estuarine wetland vegetation resources. These incremental impacts would be in

addition to similar impacts for other barrier island restoration efforts across the

Louisiana coastal area by other Federal, State, and local barrier island restoration

efforts.

5.6.3 Upland Vegetation Resources

5.6.3.1 No Action Alternative (Future without Project Conditions)

5.6.3.1.1 Direct

The No Action Alternative, not implementing the Terrebonne Basin barrier islands

restoration project, would have no direct impacts to upland vegetation as no such

resources are present on the barrier islands. However, existing conditions, including

the continued loss of upland vegetation resources within the adjacent Terrebonne

Basin estuarine system would persist.

5.6.3.1.2 Indirect

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There are no existing upland vegetation resources on the Terrebonne Basin barrier

islands. Hence, without any action there would be no indirect impacts on the

Terrebonne Basin barrier islands to upland vegetation resources.

Without any action, approximately 3,220 acres of existing barrier resources from

the seven island Terrebonne Basin barrier system (East Timbalier, Timbalier,

Trinity, East Island, Wine, Whiskey and Raccoon Island) would likely continue to

degrade, fragment and eventually convert into shallow open water bottoms over the

50-year period of analysis. The loss of the Terrebonne Basin barrier island system

would consequently result in higher wave energy levels and associated shoreline

erosion in the adjacent estuarine bays (Stone and McBride 1998, Stone et al 2003,

and Stone et al. 2005). Some unknown portions of the adjacent estuarine systems,

along with their upland vegetation resources, would be transformed into open water

habitat.

The loss of estuarine upland vegetation resources would result in adverse impacts

to wildlife habitat (e.g., used for nesting, feeding, and roosting habitats). The

degradation and eventual loss of estuarine upland vegetation resources would also

result in the loss of available wildlife habitats which would likely increase

competition between and within various wildlife species for diminishing upland

habitat resources. The loss of estuarine upland vegetated habitat would also result

in a loss in primary productivity, as well as undetermined impacts to recreation,

aesthetic and associated socioeconomic resources.

5.6.3.1.3 Cumulative

The incremental cumulative impacts of the No Action Alternative would be the

conversion of some unknown acreage of estuarine upland vegetation resources due

to the higher wave energy levels and associated shoreline erosion (Stone and

McBride 1998, Stone et al 2003, and Stone et al. 2005) resulting from the loss of the

Terrebonne Basin barrier island system and other coastal Louisiana barrier

systems.

These impacts would be offset, to some degree, by the synergistic additive

combination of impacts and benefits of coastal barrier island restoration by other

Federal, State, local, and private restoration efforts that would protect adjacent

estuarine systems, and their associated upland vegetation resources, from

converting to shallow open water habitats. Coastal barrier islands in Louisiana

have been restored, to some degree, by efforts under the CWPPRA program, and the

beneficial use of dredged material requirements under Section 307 of the Coastal

Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.6.3.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.6.3.2.1 Direct

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There would be no direct impacts to upland wetland vegetation as no such resources

are present on the Terrebonne Basin barrier islands. Hence, direct impacts of

implementing Alternative 5 (NER Plan) would be similar to the No Action

Alternative.

5.6.3.2.2 Indirect

There would be no indirect impacts of implementing Alternative 5 (NER Plan) on

the Terrebonne Basin barrier islands as there are no upland vegetation resources

on the barrier islands.

However, compared to the No Action Alternative, implementing Alternative 5 (NER

Plan) would restore a net total of 2,781 acres on Raccoon, Timbalier, Trinity, and

Whiskey Islands. Restoring these barrier islands to their minimal

geormorphological form would result, consistent with Stone and McBride (1998),

Stone et al. (2003) and Stone et al. (2005), in the restored barrier islands absorbing

wave energy during storms and fair-weather conditions and providing some storm

surge protection. Restoring the Terrebonne Basin barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the estuarine system, especially upland vegetation resources, to open

water habitat.

Implementing Alternative 5 (NER Plan) would restore four of the seven Terrebonne

barrier islands to their minimal geormorphological form thereby reducing, to some

undetermined level, the loss of adjacent estuarine upland vegetation resources.

This action would prevent/reduce the conversion of some unknown portion of the

existing back bay estuarine system and its upland vegetation resources into more

open water system.

The estuarine upland vegetation resources would, in turn, provide important

transitional habitat between estuarine and terrestrial environments as well as

unique wildlife habitat (e.g., nesting, feeding, and roosting habitats). In addition,

preventing/reducing the loss of estuarine upland vegetation resources would provide

important wildlife habitat which would likely decrease competition between and

within various wildlife species for diminishing habitat resources. The

prevention/reduction of loss of upland vegetated habitat would also result in an

undetermined increase in primary productivity compared to the No Action

Alternative.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

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advancing by some unknown extent, the economic development of the State of

Louisiana.

5.6.3.2.3 Cumulative

Cumulative impacts would be the incremental impacts to upland vegetation

resources from implementing Alternative 5 (NER Plan) when added to all past,

present and reasonably foreseeable barrier restoration efforts. Alternative 5 (NER

Plan) would restore the geomorphologic form and ecological function to a net total of

2,781 acres of Terrebonne barrier island resources. Restoration of the

geomorphologic form to Raccoon, Whiskey, Trinity and Timbalier Islands would,

consistent with Stone (2005), enable these barrier islands to maintain their

ecological function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne interior estuarine marshes and

associated upland vegetation resources. These incremental impacts would be in

addition to similar impacts for other barrier island restoration efforts across the

Louisiana coastal area by other Federal, State, and local barrier island restoration

efforts.

5.6.3.3 Alternative 11: Whiskey (Plan C)

5.6.3.3.1 Direct

There would be no direct impacts to upland wetland vegetation as no such resources

are present on the Terrebonne Basin barrier islands. Hence, direct impacts of

implementing Alternative 11 would be similar to the No Action Alternative.

5.6.3.3.2 Indirect

There would be no indirect impacts of implementing Alternative 11 on the

Terrebonne Basin barrier islands as there are no upland vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to upland vegetation

resources of implementing Alternative 11 would be similar to those described for

the Whiskey Island component of Alternative 5 (NER) but to a lesser degree.

Alternative 11 would restore a net total of 527 acres thereby restoring Whiskey

Island to its geomorphologic form which would contribute to its ecological function

of preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially upland vegetation resources, to open water habitat.

5.6.3.3.3 Cumulative

These incremental impacts would be in addition to similar impacts for other barrier

island restoration efforts across the Louisiana coastal area by other Federal, State,

and local barrier island restoration efforts.

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Cumulative impacts would be the incremental impacts to upland vegetation

resources from implementing Alternative 11 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 11 would restore the

geomorphologic form and ecological function to a net total of 527 acres on Whiskey

Island. Restoration of the geomorphologic form to Whiskey Island would, consistent

with Stone (2005), enable this barrier island to maintain its function of absorbing

wave energy during storms and fair-weather conditions and provide some

undetermined level of storm surge protection and reduction of wave potential for

the Terrebonne interior estuarine marshes and associated upland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.6.3.4 Alternative 2: Timbalier (Plan E)

5.6.3.4.1 Direct

There would be no direct impacts to upland wetland vegetation as no such resources

are present on the Terrebonne Basin barrier islands. Hence, direct impacts of

implementing Alternative 2 would be similar to the No Action Alternative.

5.6.3.4.2 Indirect

There would be no indirect impacts of implementing Alternative 2 on the

Terrebonne Basin barrier islands as there are no upland vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to upland vegetation

resources of implementing Alternative 2 would be similar to those described for the

Whiskey Island component of Alternative 5 (NER Plan) but to a lesser degree.

Alternative 2 would restore a net total of 1,324 acres thereby restoring Timbalier

Island to its geomorphologic form which would contribute to its ecological function

of preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially upland vegetation resources, to open water habitat.

5.6.3.4.3 Cumulative

Cumulative impacts would be the incremental impacts to upland vegetation

resources from implementing Alternative 2 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 2 would restore the

geomorphologic form and ecological function to a net total of 1,324 acres on

Timbalier Island. Restoration of the geomorphologic form to Timbalier Island

would, consistent with Stone (2005), enable this barrier island to maintain its

function of absorbing wave energy during storms and fair-weather conditions and

provide some undetermined level of storm surge protection and reduction of wave

potential for the Terrebonne interior estuarine marshes and associated upland

vegetation resources. These incremental impacts would be in addition to similar

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impacts for other barrier island restoration efforts across the Louisiana coastal area

by other Federal, State, and local barrier island restoration efforts.

5.6.3.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.6.3.5.1 Direct

There would be no direct impacts to upland wetland vegetation as no such resources

are present on the Terrebonne Basin barrier islands. Hence, direct impacts of

implementing Alternative 3 would be similar to the No Action Alternative.

5.6.3.5.2 Indirect

There would be no indirect impacts of implementing Alternative 3 on the

Terrebonne Basin barrier islands as there are no upland vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to upland vegetation

resources of implementing Alternative 3 would be similar to those described for the

Whiskey and Timbalier Islands components of Alternative 5 (NER Plan) but to a

lesser degree. Alternative 3 would restore a net total of 1,851 acres thereby

restoring Whiskey and Timbalier Islands to their geomorphologic forms which

would contribute to their ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine system, especially upland vegetation

resources, to open water habitat.

5.6.3.5.3 Cumulative

Cumulative impacts would be the incremental impacts to upland vegetation

resources from implementing Alternative 3 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 3 would restore the

geomorphologic form and ecological function to a net total of 1,851 acres on Whiskey

and Timbalier Islands. Restoration of the geomorphologic form to Whiskey and

Timbalier Islands would, consistent with Stone (2005), enable these barrier islands

to maintain their function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne interior estuarine marshes and

associated upland vegetation resources. These incremental impacts would be in

addition to similar impacts for other barrier island restoration efforts across the

Louisiana coastal area by other Federal, State, and local barrier island restoration

efforts.

5.6.3.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.6.3.6.1 Direct

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There would be no direct impacts to upland wetland vegetation as no such resources

are present on the Terrebonne Basin barrier islands. Hence, direct impacts of

implementing Alternative 4 would be similar to the No Action Alternative.

5.6.3.6.2 Indirect

There would be no indirect impacts of implementing Alternative 4 on the

Terrebonne Basin barrier islands as there are no upland vegetation resources on

the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to upland vegetation

resources of implementing Alternative 4 would be similar to those described for the

Whiskey, Trinity and Timbalier Islands components of Alternative 4 but to a lesser

degree. Alternative 4 would restore a net total of 2,140 acres thereby restoring

Whiskey, Trinity and Timbalier Islands to their geomorphologic forms which would

contribute to their ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine system, especially upland vegetation resources, to open

water habitat.

5.6.3.6.3 Cumulative

Cumulative impacts would be the incremental impacts to upland vegetation

resources from implementing Alternative 4 when added to all past, present and

reasonably foreseeable barrier restoration efforts. Alternative 4 would restore the

geomorphologic form and ecological function to a net total of 2,140 acres on

Whiskey, Trinity and Timbalier Islands. Restoration of the geomorphologic form to

Whiskey, Trinity and Timbalier Islands would, consistent with Stone (2005), enable

these barrier islands to maintain their function of absorbing wave energy during

storms and fair-weather conditions and provide some undetermined level of storm

surge protection and reduction of wave potential for the Terrebonne interior

estuarine marshes and associated upland vegetation resources. These incremental

impacts would be in addition to similar impacts for other barrier island restoration

efforts across the Louisiana coastal area by other Federal, State, and local barrier

island restoration efforts.

5.6.4 Submerged Aquatic Vegetation (SAV)

5.6.4.1 No Action Alternative (Future without Project Conditions)

5.6.4.1.1 Direct

The No Action Alternative, not implementing the LCA TBBSR Study, would have

no direct impacts to submerged aquatic vegetation as no such resources are present

on the barrier islands. However, existing conditions, including the continued loss of

submerged aquatic vegetation resources within the adjacent Terrebonne Basin

estuarine system would persist.

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5.6.4.1.2 Indirect

There are no existing submerged aquatic vegetation resources on the Terrebonne

Basin barrier islands. Hence, without any action there would be no indirect impacts

on the Terrebonne Basin barrier islands to submerged aquatic vegetation resources.

Without any action, approximately 3,220 acres of existing barrier resources from

the seven island Terrebonne Basin barrier system (East Timbalier, Timbalier,

Trinity, East Island, Wine, Whiskey and Raccoon Island) would likely continue to

degrade, fragment and eventually convert into shallow open water bottoms over the

50-year period of analysis. The loss of the Terrebonne Basin barrier island system

would consequently result in higher wave energy levels and associated shoreline

erosion in the adjacent estuarine bays (Stone and McBride 1998, Stone et al 2003,

and Stone et al. 2005). Some unknown portions of the adjacent estuarine systems,

along with their submerged aquatic vegetation resources, would be transformed into

marine open water habitat. It is likely more marine-like conditions would not be

conducive to maintaining or establishing submerged aquatic vegetation.

The loss of estuarine submerged aquatic vegetation resources would result in

adverse impacts to fish and wildlife habitats (e.g., used for nursery, nesting and

feeding habitats). The degradation and eventual loss of estuarine submerged

aquatic vegetation resources would also result in the loss of available fish and

wildlife habitats which would likely increase competition between and within

various fish and wildlife species for diminishing submerged aquatic habitat

resources. The loss of estuarine submerged aquatic vegetated habitat would also

result in a loss in primary productivity, as well as undetermined impacts to

recreation, aesthetic and associated socioeconomic resources.

5.6.4.1.3 Cumulative

The incremental cumulative impacts of the No Action Alternative would be the

conversion of some unknown acreage of estuarine submerged aquatic vegetation

resources due to the higher wave energy levels and associated shoreline erosion

(Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005) resulting from

the loss of the Terrebonne Basin barrier island system and other coastal Louisiana

barrier systems and the resulting conversion from estuarine-like conditions to more

marine-like conditions.

These impacts would be offset, to some degree, by the synergistic additive

combination of impacts and benefits of coastal barrier island restoration by other

Federal, State, local, and private restoration efforts that would protect adjacent

estuarine systems, and their associated submerged aquatic vegetation resources,

from converting to shallow open water habitats. Coastal barrier islands in

Louisiana have been restored, to some degree, by efforts under the CWPPRA

program, and the beneficial use of dredged material requirements under Section

307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

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5.6.4.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.6.4.2.1 Direct

There would be no direct impacts to submerged aquatic wetland vegetation as no

such resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 5 (NER Plan) would be similar to the No

Action Alternative.

5.6.4.2.2 Indirect

There would be no indirect impacts of implementing Alternative 5 (NER Plan) on

the Terrebonne Basin barrier islands as there are no submerged aquatic vegetation

resources on the barrier islands.

However, compared to the No Action Alternative, implementing Alternative 5 (NER

Plan) would restore a net total of 2,781 acres on Raccoon, Timbalier, Trinity, and

Whiskey Islands. Restoring these barrier islands to their minimal

geormorphological form would result, consistent with Stone and McBride (1998),

Stone et al. (2003) and Stone et al. (2005), in the restored barrier islands absorbing

wave energy during storms and fair-weather conditions and providing some storm

surge protection. Restoring the Terrebonne Basin barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the estuarine system, especially submerged aquatic vegetation

resources, to open water habitat.

Implementing Alternative 5 (NER Plan) would restoring four of the seven

Terrebonne barrier islands to their minimal geormorphological form thereby

reducing, to some undetermined level, the loss of adjacent estuarine submerged

aquatic vegetation resources. This action would prevent/reduce the conversion of

some unknown portion of the existing back bay estuarine system and its submerged

aquatic vegetation resources into more open water system.

The estuarine submerged aquatic vegetation resources would, in turn, provide

important transitional habitat between estuarine and terrestrial environments as

well as unique fish and wildlife habitat (e.g., nursery, nesting, and feeding

habitats). In addition, preventing/reducing the loss of estuarine submerged aquatic

vegetation resources would provide important fish and wildlife habitat which would

likely decrease competition between and within various wildlife species for

diminishing habitat resources. The prevention/reduction of loss of submerged

aquatic vegetated habitat would also result in an undetermined increase in primary

productivity compared to the No Action Alternative.

5.6.4.2.3 Cumulative

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Cumulative impacts would be the incremental impacts to submerged aquatic

vegetation resources from implementing Alternative 5 (NER Plan) when added to

all past, present and reasonably foreseeable barrier restoration efforts. Alternative

5 (NER Plan) would restore the geomorphologic form and ecological function to a

net total of 2,781 acres of Terrebonne barrier island resources. Restoration of the

geomorphologic form to Raccoon, Whiskey, Trinity and Timbalier Islands would,

consistent with Stone (2005), enable these barrier islands to maintain their

ecological function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne interior estuarine marshes and

associated submerged aquatic vegetation resources. These incremental impacts

would be in addition to similar impacts for other barrier island restoration efforts

across the Louisiana coastal area by other Federal, State, and local barrier island

restoration efforts.

5.6.4.3 Alternative 11: Whiskey (Plan C)

5.6.4.3.1 Direct

There would be no direct impacts to submerged aquatic wetland vegetation as no

such resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 11 would be similar to the No Action

Alternative.

5.6.4.3.2 Indirect

There would be no indirect impacts of implementing Alternative 11 on the

Terrebonne Basin barrier islands as there are no submerged aquatic vegetation

resources on the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to submerged aquatic

vegetation resources of implementing Alternative 11 would be similar to those

described for the Whiskey Island component of Alternative 5 (NER) but to a lesser

degree. Alternative 11 would restore a net total of 527 acres thereby restoring

Whiskey Island to its geomorphologic form which would contribute to its ecological

function of preventing conversion of the adjacent Terrebonne Basin estuarine

system, especially submerged aquatic vegetation resources, to open water habitat.

5.6.4.3.3 Cumulative

These incremental impacts would be in addition to similar impacts for other barrier

island restoration efforts across the Louisiana coastal area by other Federal, State,

and local barrier island restoration efforts.

Cumulative impacts would be the incremental impacts to submerged aquatic

vegetation resources from implementing Alternative 11 when added to all past,

present and reasonably foreseeable barrier restoration efforts. Alternative 11 would

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restore the geomorphologic form and ecological function to a net total of 527 acres

on Whiskey Island. Restoration of the geomorphologic form to Whiskey Island

would, consistent with Stone (2005), enable this barrier island to maintain its

function of absorbing wave energy during storms and fair-weather conditions and

provide some undetermined level of storm surge protection and reduction of wave

potential for the Terrebonne interior estuarine marshes and associated submerged

aquatic vegetation resources. These incremental impacts would be in addition to

similar impacts for other barrier island restoration efforts across the Louisiana

coastal area by other Federal, State, and local barrier island restoration efforts.

5.6.4.4 Alternative 2: Timbalier (Plan E)

5.6.4.4.1 Direct

There would be no direct impacts to submerged aquatic wetland vegetation as no

such resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 2 would be similar to the No Action

Alternative.

5.6.4.4.2 Indirect

There would be no indirect impacts of implementing Alternative 2 on the

Terrebonne Basin barrier islands as there are no submerged aquatic vegetation

resources on the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to submerged aquatic

vegetation resources of implementing Alternative 2 would be similar to those

described for the Whiskey Island component of Alternative 5 (NER Plan) but to a

lesser degree. Alternative 2 would restore a net total of 1,324 acres thereby

restoring Timbalier Island to its geomorphologic form which would contribute to its

ecological function of preventing conversion of the adjacent Terrebonne Basin

estuarine system, especially submerged aquatic vegetation resources, to open water

habitat.

5.6.4.4.3 Cumulative

Cumulative impacts would be the incremental impacts to submerged aquatic

vegetation resources from implementing Alternative 2 when added to all past,

present and reasonably foreseeable barrier restoration efforts. Alternative 2 would

restore the geomorphologic form and ecological function to a net total of 1,324 acres

on Timbalier Island. Restoration of the geomorphologic form to Timbalier Island

would, consistent with Stone (2005), enable this barrier island to maintain its

function of absorbing wave energy during storms and fair-weather conditions and

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provide some undetermined level of storm surge protection and reduction of wave

potential for the Terrebonne interior estuarine marshes and associated submerged

aquatic vegetation resources. These incremental impacts would be in addition to

similar impacts for other barrier island restoration efforts across the Louisiana

coastal area by other Federal, State, and local barrier island restoration efforts.

5.6.4.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.6.4.5.1 Direct

There would be no direct impacts to submerged aquatic wetland vegetation as no

such resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 3 would be similar to the No Action

Alternative.

5.6.4.5.2 Indirect

There would be no indirect impacts of implementing Alternative 3 on the

Terrebonne Basin barrier islands as there are no submerged aquatic vegetation

resources on the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to submerged aquatic

vegetation resources of implementing Alternative 3 would be similar to those

described for the Whiskey and Timbalier Islands components of Alternative 5 (NER

Plan) but to a lesser degree. Alternative 3 would restore a net total of 1,851 acres

thereby restoring Whiskey and Timbalier Islands to their geomorphologic forms

which would contribute to their ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine system, especially submerged aquatic

vegetation resources, to open water habitat.

5.6.4.5.3 Cumulative

Cumulative impacts would be the incremental impacts to submerged aquatic

vegetation resources from implementing Alternative 3 when added to all past,

present and reasonably foreseeable barrier restoration efforts. Alternative 3 would

restore the geomorphologic form and ecological function to a net total of 1,851 acres

on Whiskey and Timbalier Islands. Restoration of the geomorphologic form to

Whiskey and Timbalier Islands would, consistent with Stone (2005), enable these

barrier islands to maintain their function of absorbing wave energy during storms

and fair-weather conditions and provide some undetermined level of storm surge

protection and reduction of wave potential for the Terrebonne interior estuarine

marshes and associated submerged aquatic vegetation resources. These incremental

impacts would be in addition to similar impacts for other barrier island restoration

efforts across the Louisiana coastal area by other Federal, State, and local barrier

island restoration efforts.

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5.6.4.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.6.4.6.1 Direct

There would be no direct impacts to submerged aquatic wetland vegetation as no

such resources are present on the Terrebonne Basin barrier islands. Hence, direct

impacts of implementing Alternative 4 would be similar to the No Action

Alternative.

5.6.4.6.2 Indirect

There would be no indirect impacts of implementing Alternative 4 on the

Terrebonne Basin barrier islands as there are no submerged aquatic vegetation

resources on the Terrebonne Basin barrier islands.

Compared to the No Action Alternative, indirect impacts to submerged aquatic

vegetation resources of implementing Alternative 4 would be similar to those

described for the Whiskey, Trinity and Timbalier Islands components of Alternative

4 but to a lesser degree. Alternative 4 would restore a net total of 2,140 acres

thereby restoring Whiskey, Trinity and Timbalier Islands to their geomorphologic

forms which would contribute to their ecological function of preventing conversion of

the adjacent Terrebonne Basin estuarine system, especially submerged aquatic

vegetation resources, to open water habitat.

5.6.4.6.3 Cumulative

Cumulative impacts would be the incremental impacts to submerged aquatic

vegetation resources from implementing Alternative 4 when added to all past,

present and reasonably foreseeable barrier restoration efforts. Alternative 4 would

restore the geomorphologic form and ecological function to a net total of 2,140 acres

on Whiskey, Trinity and Timbalier Islands. Restoration of the geomorphologic form

to Whiskey, Trinity and Timbalier Islands would, consistent with Stone (2005),

enable these barrier islands to maintain their function of absorbing wave energy

during storms and fair-weather conditions and provide some undetermined level of

storm surge protection and reduction of wave potential for the Terrebonne interior

estuarine marshes and associated submerged aquatic vegetation resources. These

incremental impacts would be in addition to similar impacts for other barrier island

restoration efforts across the Louisiana coastal area by other Federal, State, and

local barrier island restoration efforts.

5.6.5 Invasive Species  Vegetation

5.6.5.1 No Action Alternative (Future without Project Conditions)

5.6.5.1.1 Direct

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The No Action Alternative, not implementing the LCA TBBSR Study, would have no

direct impacts on invasive vegetation species as no such species are present on the

islands.

5.6.5.1.2 Indirect

The No Action Alternative, not implementing the LCA TBBSR Study, would have no

indirect impacts on invasive vegetation species as no such species are present on the

islands. In addition, it is unlikely that the eventual conversion of the Terrebonne

Basin barrier island system to shallow open water would have no indirect impacts

on invasive vegetation species within the adjacent Terrebonne Basin estuarine

system.

5.6.5.1.3 Cumulative

The No Action Alternative, not implementing the LCA TBBSR Study, would have no

cumulative impacts on invasive vegetation species either on the barrier islands or

within the adjacent Terrebonne Basin estuarine system.

5.6.5.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.6.5.2.1 Direct

No invasive vegetation species have been found on the Terrebonne Basin barrier

islands. Several barrier island restoration projects have been implemented over the

past years, with the majority (executed) through the CWPPRA program (e.g.

CWPPRA BA-76 Cheniere Ronquille Barrier Island Restoration; BA 40 Riverine

Sand Mining/Scofield Island Restoration; BA-38 Barataria Barrier Island Complex

Project; TE-27 Whiskey Island Restoration; TE-18 Timbalier island Planting

Demonstration; source:http://lacoast.gov/new/Projects/List.aspx accessed September

7, 2010). To date, no invasive species impacts resulting from those projects are

known to have been reported or documented. In addition, query of several

individuals knowledgeable of Louisiana barrier island ecosystems and current

restoration efforts yielded no reports or observations evidencing any displacement of

natural vegetative communities by invasive species (personal communication C.

Steyer, K. Bahlinger, M. Carloss, M. Hester, G.Linscombe, M. Materne, Irv

Mendelssohn, and C. Reid, J. Visser). Consequently, because this alternative would

create barrier island habitat with features on a scale similar to existing projects,

and would include native species plantings to quickly establish targeted vegetative

communities, the anticipated risk of causing conditions favorable to encroachment

and impacts by invasive species would be negligible. Hence, direct impacts of

implementing Alternative 5 (NER Plan) would be similar to the No Action

Alternative.

5.6.5.2.2 Indirect

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Indirect impacts of implementing Alternative 5 (NER Plan) would be similar to the

No Action Alternative.

5.6.5.2.3 Cumulative

Cumulative impacts of implementing Alternative 5 (NER Plan) would be similar to

the No Action Alternative.

5.6.5.3 Alternative 11: Whiskey (Plan C)

5.6.5.3.1 Direct

Direct impacts of implementing Alternative 11 would be similar to the Whiskey

Island component of Alternative 5 (NER Plan).

5.6.5.3.2 Indirect

Indirect impacts of implementing Alternative 11 would be similar to the Whiskey

Island component of Alternative 5 (NER Plan).

5.6.5.3.3 Cumulative

Cumulative impacts of implementing Alternative 11 would be similar to the

Whiskey Island component of Alternative 5 (NER Plan).

5.6.5.4 Alternative 2: Timbalier (Plan E)

5.6.5.4.1 Direct

Direct impacts of implementing Alternative 2 would be similar to the Timbalier

Island component of Alternative 5 (NER Plan).

5.6.5.4.2 Indirect

Indirect impacts of implementing Alternative 2 would be similar to the Timbablier

Island component of Alternative 5 (NER Plan).

5.6.5.4.3 Cumulative

Cumulative impacts of implementing Alternative 2 would be similar to the Timbalier

Whiskey Island component of Alternative 5 (NER Plan).

5.6.5.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.6.5.5.1 Direct

Direct impacts of implementing Alternative 3 would be similar to the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan).

5.6.5.5.2 Indirect

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Indirect impacts of implementing Alternative 3 would be similar to the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan).

5.6.5.5.3 Cumulative

Cumulative impacts of implementing Alternative 3 would be similar to the Whiskey

Island component of Alternative 5 (NER Plan).

5.6.5.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.6.5.6.1 Direct

Direct impacts of implementing Alternative 4 would be similar to the Whiskey, Trinity

and Timbalier Islands components of Alternative 5 (NER Plan).

5.6.5.6.2 Indirect

Indirect impacts of implementing Alternative 4 would be similar to the Whiskey,

Trinity and Timbalier Islands components of Alternative 5 (NER Plan).

5.6.5.6.3 Cumulative

Cumulative impacts of implementing Alternative 4 would be similar to the Whiskey,

Trinity and Timbalier Islands components of Alternative 5 (NER Plan).

5.7 WILDLIFE AND HABITAT

5.7.1.1 No Action Alternative (Future without Project Conditions)

5.7.1.1.1 Direct

The No Action Alternative, not implementing Terrebonne Basin barrier shoreline

restoration, would have no direct impacts on wildlife and habitat resources.

Existing conditions would persist. The Terrebonne Basin barrier shoreline would

continue to degrade, fragment and eventually convert to primarily marineinfluenced open water which would continue to adversely impact foraging, nesting,

wintering, resting, refugia, and other important wildlife habitats for resident and

migratory birds and other wildlife. The dwindling availability of suitable barrier

and back barrier marsh habitats for use by wildlife is expected to result in a general

decline of wildlife populations throughout the Terrebonne Basin in general, and the

Study Area specifically. Direct adverse impacts to wildlife may also result from

events such as tropical storms and hurricanes, but are expected to be smaller in

comparison to indirect impacts.

5.7.1.1.2 Indirect

The No Action Alternative would continue to degrade, fragment and eventually

convert 3,220 acres of existing Terrebonne Basin barrier island beach, dune and

intertidal wildlife habitats to marine-dominated open water bottom habitat over the

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50-year period of analysis. The loss of the Terrebonne Basin barrier island system

would consequently result in higher wave energy levels and associated shoreline

erosion in the adjacent estuarine bays (Stone and McBride 1998, Stone et al 2003,

and Stone et al. 2005). Some unknown portions of the adjacent Terrebonne Basin

estuarine systems, along with their wildlife habitat resources, would be

transformed into shallow open water habitat.

The loss of 3,220 acres of existing barrier island and adjacent estuarine wildlife

habitats would adversely impact important transitional habitat between estuarine

and marine environments; essential fish habitat (EFH); unique wildlife habitat

(e.g., nursery, nesting, feeding, and roosting habitats); and critical wintering

habitat for the threatened piping plover (Britton and Morton, 1989; Day et al. 1989).

The continued degradation and eventual loss of wildlife habitat resources would

likely increase competition between and within various fish and wildlife species for

diminishing barrier and estuarine habitat resources. The loss of vegetated barrier

island wetlands and estuarine islands would also result in a loss in primary

productivity. In the long-term, as marine-influenced open water replaces

transitional barrier island wildlife habitats and shallow open water replaces

existing estuarine wildlife habitats, the extent of land-to-water interface would

decrease and wildlife productivity would also likely decline.

5.7.1.1.3 Cumulative

The projected loss over all seven of the Terrebonne barrier islands of about 3,220

acres of barrier island wildlife habitat by 2062 would be in synergistic combination

with an unknown area of adjacent existing Terrebonne Basin estuarine wildlife

habitats converting to open water habitat following the collapse of the Terrebonne

Basin barrier shoreline system. Existing barrier and estuarine wildlife habitat

would convert to shallow open water thereby causing wildlife species to move to

areas that better support their habitat requirements.

Impacts from the loss of the Terrebonne Basin barrier island system and adjacent

estuarine system would be in addition to the projected loss of wildlife and habitat

resources throughout coastal Louisiana and the Nation. The LCA Study (USACE,

2004) estimated coastal Louisiana would continue to lose land at a rate of

approximately 6,600 acres per year over the next 50 years. Louisiana has lost

approximately 1,900 square miles (492,097 ha) of coastal wildlife habitat resources

since the 1930's (Dunbar et al. 1992; Barras et al. 1994; Barras et al. 2003).

Approximately 10 percent of Louisianas remaining coastal wetlands would be lost

at a rate of approximately 6,600 acres per year (2,672 ha per year) over the next 50

years, resulting in an additional net loss of 328,000 acres (132,794 ha) by 2050

(Barras et al. 2003). Coastal barrier wildlife habitat loss and estuarine wildlife

habitat loss in Louisiana has been addressed, to some degree, by efforts under the

Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) program,

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and the beneficial use of dredged material requirements under Section 307 of the

Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

5.7.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.7.1.2.1 Direct

Compared to the No Action Alternative, direct impacts to wildlife and habitat

resources of implementing Alternative 5 (NER Plan) would primarily result from

initial construction and re-nourishment construction activities related to placement

of borrow material on existing fragmented dune, supratidal, intertidal (gulfside and

bayside) and shallow open water habitats that would make these habitats

temporarily unavailable and could disrupt or displace wildlife utilizing these

habitats. Alternative 5 (NER Plan) would initially restore a total of 5,840 acres on

Raccoon, Whiskey, Trinity, and Timbalier Islands including a total of 472 acres of

dune, 4,320 acres of supratidal and 1,048 acres of intertidal wildlife habitats for use

by various wildlife species.

Alternative 5 (NER Plan) would initially restore a total of 789 acres of wildlife

habitat resources on Raccoon Island, including restoration of 239 acres of existing

degrading wildlife habitats and creation of an additional 554 acres of wildlife

habitats resources. Additional direct impacts would include renourishment at

target year 30 (TY30) of 658 acres of beach and dune wildlife habitat resources

along Raccoon Island.

Alternative 5 (NER Plan) would initially restore a total of 1,272 acres of wildlife

habitat resources on Whiskey Island including restoration of 820 acres of existing

degrading wildlife habitat resources and creation of an additional 469 acres of

wildlife habitat resources. Additional direct impacts would include renourishment of

929 acres and 905 acres of beach and dune wildlife habitat resources at TY20 and

TY 40, respectively.

Alternative 5 (NER Plan) would initially restore a total of 1,149 acres of wildlife

habitat resources on Trinity Island including restoration of 582 acres of existing

degrading wildlife habitat resources and creation of an additional 585 acres of

wildlife habitat resources. Additional direct impacts would include renourishment

of 1,151 acres of beach and dune wildlife habitat resources at TY25.

Alternative 5 (NER Plan) would initially restore a total of 2,630 acres of wildlife

habitat resources on Timablier island including restoration of 979 acres of existing

degrading wildlife habitat resources and creation of an additional 1,675 acres of

wildlife habitat resources. Additional direct impacts would include renourishment of

1,786 acres of beach and dune wildlife habitat resources at TY 30.

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Placement of borrow material would unavoidably bury existing barrier shoreline,

dune, marsh, and shallow water bottom wildlife habitat resources. Following

placement, consolidation of borrow material would take about one year.

Construction of the terminal groin on Raccoon Island would result in 2 acres of

these existing shallow water bottoms to be permanently unavailable for use by

wildlife.

Migratory Bird and Colonial Nesting Bird Impacts

The USACE Biological Assessment (Appendix A) and the USFWS Biological

Opinion (Appendix A) provide more detailed description of impacts to migratory

birds and colonial nesting wading birds. Construction activities could disturb or

potentially result in a Take of colonial-nesting wading birds, terns, gulls,

skimmers, shorebirds, or brown pelicans during the estimated 2,480-day

construction period. The Migratory Bird Treaty Act of 1918, as amended (MBTA),

established a Federal prohibition, unless permitted by regulations, to:

pursue, hunt, take, capture, kill, attempt to take, capture or kill, possess, offer

for sale, sell, offer to purchase, purchase, deliver for shipment, ship, cause to

be shipped, deliver for transportation, transport, cause to be transported carry,

or cause to be carried by any means whatever, receive for shipment,

transportation or carriage, or export, at any time, or in any manner, any

migratory bird, included in the terms of this convention  for the protection of

migratory birds  or any part, nest, or egg of any such bird. (16 U.S.C. 703)

All colonial nesting, wading and water birds, and shorebirds are protected by the

MBTA. The MBTA prohibits Take of these species and Executive Order 13186 of

2001(Responsibilities of Federal Agencies to Protect Migratory Birds) requires that

actions by Federal agencies be designed to avoid and minimize impacts to migratory

birds. The MBTA prohibits the capture or lethal take of migratory birds; however,

the MBTA does not prohibit harassment of migratory birds.

The USFWS and LDWF requires 1,000-ft no work areas around active colonial

wading-bird nesting colonies during the nesting season (February 15 through

September 1). However, the extended length of construction for Alternative 5 (NER

Plan), estimated 2,480-day construction period, will require the USACE to continue

coordinating with the USFWS and LDWF in order to determine appropriate

prevention and abatement procedures to prevent the disturbance and/or takings of

nesting birds.

The key to deterring colonial wading birds and other shorebirds from establishing

active nesting colonies is timing, persistence, organization, and diversity of

abatement measures. The USACE will develop a Nesting Prevention Plan, in

coordination with the USFWS and LDWF, that outlines known habitat conditions of

the Study Area, expected and potential colonial wading birds and other migratory

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birds, regulatory overview of Federal and State statutes relating to the

implementation of a Nesting Prevention Plan, proposed abatement methods and

techniques, safety and communication plans, ambient noise study implementation,

monitoring of the Study Area, and reporting the status of the abatement measures.

All abatement measures would be conducted by biologists familiar with colonial

wading bird ecology and with proposed abatement methods (e.g., stationary and

active audio and visual repellents and others). Prior to and during the nesting

season, the Study Area would be inspected by qualified personnel for the presence of

nesting colonies during the nesting season. In addition to surveillance, nesting

prevention measures would be employed to discourage and prevent wading birds

from nesting within a 1,000 ft range of the Study Areas. Active nesting prevention

measures would be coordinated with the USFWS and LDWF and likely required

from January to September during the year of construction.

If measures to prevent colonial nesting bird populations are not successful in the

Study Area, construction-related activities that would occur within 1,000 ft of a

colony could be restricted to the non-nesting period, which in this region generally

extends from September 1 to February 15, depending on the species present. This

restriction would likely pose significant problems to construction activity schedules.

If wading bird nesting colonies become established in the Study Area, the 1,000 ft

buffer must be maintained unless coordination with the USFWS indicates that the

buffer zone may be reduced based on the species present or an agreement is reached

with USFWS that allows a modified process to be adopted.

Most of the Terrebonne Basin barrier shoreline is designated as critical wintering

habitat for the endangered piping plover (Federal Register, Vol. 66, No. 132). The

Endangered Species Act of 1973 (ESA), as amended, prohibits unauthorized taking

of endangered or threatened species. Section 7 of the ESA requires Federal agencies

to ensure that any action authorized, funded or carried out by them is not likely to

jeopardize the continued existence of listed species or modify their critical habitat.

The USACE will continue to closely coordinate with the USFWS and LDWF in

determining specific actions to avoid and minimize potential impacts to these

species and their critical habitat. Therefore, abatement measures to prevent

colonial wading-bird nesting should not disturb interior least terns or piping plovers

on their wintering habitat.

Louisiana State law also protects species listed as threatened or endangered under

the ESA, or species determined by the secretary of the LDWF to be threatened or

endangered. The brown pelican and interior least tern are listed as State

endangered; piping plover is listed as State threatened. The taking of any State

threatened or endangered species is prohibited by State law; therefore, abatement

measures to prevent colonial wading-bird nesting should not disturb brown

pelicans, interior least terns or piping plovers on their critical wintering habitat.

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In order to minimize potential impacts to migratory bird species, the sequencing of

barrier island construction could also allow these birds to temporarily relocate to

nearby suitable habitat within the Study Area. For example, the proposed beach

and dune components of Whiskey and Trinity Island would be constructed before

the marsh templates. Once construction of the beach and dune are completed on

these two islands, construction would begin on the marsh templates. At that point,

the beaches would begin to recover. Raccoon Island would remain undisturbed

during sediment placement on Whiskey and Trinity and thus would provide

suitable habitat for displaced birds. Furthermore, East Island (which is a

continuation of Trinity Island) and East Timbalier (which is adjacent to Timbalier

Island) are not part of the proposed restoration efforts for Alternative 5 (NER Plan)

and would therefore also provide suitable habitat for the birds during construction

of the other islands. Prey species smothered by dune and beach creating activities

would re-colonize in the Study boundary within two years following completion of

construction activities (USFWS, 2010a). Therefore, by the time construction

activities commence on Raccoon Island, the benthic communities on the Whiskey

and Trinity Island beaches should be in the recovery phase.

During the preconstruction and engineering (PED) phase, the USACE will continue

to coordinate with the USFWS and LDWF to further assess construction sequencing

and determine the feasibility of staggering construction such that only one island is

disturbed at any point in time. This would minimize disturbance to the piping

plover during construction and maintain an abundance of critical wintering habitat

within the immediate vicinity of the construction area.

Staggered implementation of renourishment events would also be considered to

minimize potential adverse impacts to colonial-nesting wading birds, terns, gulls,

skimmers, shorebirds, or brown pelicans. However, as with initial construction,

staggering construction could significantly delay project implementation and

completion.

5.7.1.2.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 5 (NER Plan) would be a net increase of 2,781 acres with 2,883 AAHUs

of important and essential vegetated wildlife habitats used by fish and wildlife for

shelter, nesting, feeding, roosting, cover, nursery and other life requirements;

increased vegetation growth and productivity; and reduced inter- and intra-specific

species competition between resident and non-resident fish and wildlife species for

limited coastal vegetation.

Alternative 5 (NER Plan) would restore and rehabilitate dune, supratidal and

intertidal coastal barrier habitats for use by various wildlife species; reduce

conversion of these habitats to marine-dominated open water habitat; and provide

higher quality EFH, especially nursery habitat, for several species, including brown

and white shrimp, and blue crab. Vegetative plantings would contribute to re514
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establishing a variety of wetland species that would further aid in sediment

trapping and barrier island stabilization. Vegetative productivity would likely

increase due to increased in vegetated acres on the barrier islands. Important

stopover habitats used by migrating neotropical birds would be restored and

sustained for future use over the 50-year period of analysis. Compared to the No

Action Alternative, implementing Alternative 5 (NER Plan) would delay the

conversion of important barrier wildlife habitats to marine-dominated open water

habitats over the 50-year period of analysis.

In addition, compared to the No Action Alternative, implementing Alternative 5

(NER Plan) would restore Raccoon, Timbalier, Trinity, and Whiskey Islands to their

minimal geormorphological form which would result, consistent with Stone and

McBride (1998), Stone et al. (2003) and Stone et al. (2005), in the restored barrier

islands absorbing wave energy during storms and fair-weather conditions and

providing some storm surge protection. Restoring these four barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the adjacent Terrebonne Basin estuarine system, especially wildlife

habitat resources, to shallow open water habitat.

The protected estuarine wetland vegetation resources would, in turn, provide

important transitional habitat between estuarine and terrestrial environments as

well as unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting

habitats). In addition, preventing/reducing the loss of estuarine wildlife habitat

resources would provide important wildlife habitat which would likely decrease

competition between and within various wildlife species for diminishing habitat

resources. The prevention/reduction of loss of wildlife habitats would also result in

an undetermined increase in primary productivity compared to the No Action

Alternative.

Implementing Alternative 5 (NER Plan) would also restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana..

5.7.1.2.3 Cumulative

Cumulative impacts would be the incremental impact from implementing

Alternative 5 (NER Plan) when added to all past, present and reasonably

foreseeable similar barrier wildlife and habitat restoration efforts. Alternative 5

(NER Plan) would restore a net total of 2,781 acres with 2,883 AAHUs of dune,

supratidal, intertidal (gulfside and bayside) and shallow open water wildlife

habitats which would be in addition to impacts and benefits for overall net acres of

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barrier wildlife habitat resources created, nourished, restored, and/or protected by

other Federal, State, local, and private restoration efforts.

In addition, Alternative 5 (NER Plan) would restore the geomorphologic form to

Raccoon, Whiskey, Trinity and Timbalier Islands that would, consistent with Stone

(2005), enable these barrier islands to maintain their ecological function of

absorbing wave energy during storms and fair-weather conditions and provide some

undetermined level of storm surge protection and reduction of wave potential for

the Terrebonne interior estuarine wildlife habitat resources. These restoration

efforts would be in addition to other ongoing Federal, State and local restoration

efforts. Coastal barrier land loss in Louisiana has been addressed, to some degree,

by efforts under the Coastal Wetlands Planning, Protection and Restoration Act

(CWPPRA) program, and the beneficial use of dredged material requirements under

Section 307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

TY50..

5.7.1.3 Alternative 11: Whiskey (Plan C with renourishment)

5.7.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to wildlife and habitat

resources of implementing Alternative 11 would be similar to those described for

the Whiskey Island component of Alternative 5 (NER Plan), including initial

restoration of a total 1,272 acres with 678 AAHUs with 65 acres of dune, 830 acres

of supratidal, 377 acres of intertidal wildlife habitat resources on Whiskey Island.

5.7.1.3.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wildlife and habitat

resources of implementing Alternative 11 would be similar to those described for

the Whiskey Island component of Alternative 5 (NER). Alternative 11 would restore

a net total of 527 acres of wildlife habitat resources with 0 net acres dune, 164 net

acres supratidal, and 363 net acres of intertidal wildlife habitat resources over the

50-year period of analysis. In addition, Alternative 11 would restore Whiskey

Island to its minimal geomorphologic form which would contribute to its ecological

function of preventing conversion of the adjacent Terrebonne Basin estuarine

system, especially wildlife habitat resources, to open water habitat.

5.7.1.3.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres with 678 AAHUs of

wildlife and habitat resources on Whiskey Island.

Alternative 11 would also restore the minimal geomorphologic form to Whiskey

Island that would, consistent with Stone (2005), enable this barrier island to

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maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.7.1.4 Alternative 2: Timbalier (Plan E)

5.7.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to wildlife and habitat

resources of implementing Alternative 2 would be similar to those described for the

Timbalier Island component of Alternative 5 (NER Plan), including initial

restoration of a total 2,630 acres with 1,110 AAHUs with 215 acres of dune, 2,346

acres of supratidal, 69 acres of intertidal wildlife habitat resources on Timbalier

Island.

5.7.1.4.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wildlife and habitat

resources of implementing Alternative 2 would be similar to those described for the

Timbalier Island component of Alternative 5 (NER Plan). Alternative 2 would

restore a net total of 1,324 acres of wildlife habitat resources with 0 net acres dune,

236 net acres supratidal, and 1,088 net acres of intertidal wildlife habitat resources

over the 50-year period of analysis. In addition, Alternative 2 would restore

Timbalier Island to its minimal geomorphologic form which would contribute to its

ecological function of preventing conversion of the adjacent Terrebonne Basin

estuarine system, especially wildlife habitat resources, to open water habitat).

5.7.1.4.3 Cumulative

Cumulative impacts would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 restoring a net total of 1,324 acres with 1,100 AAHUs of

wildlife and habitat resources on Timbalier Island.

Alternative 2 would also restore the minimal geomorphologic form to Timbalier

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

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other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.7.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.7.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to wildlife and habitat

resources of implementing Alternative 3 would be similar to those described for the

Whiskey and Timbalier Islands component of Alternative 5 (NER Plan), including

initial restoration of a total 3,902 acres with 1,778 AAHUs with 280 acres of dune,

3176 acres of supratidal, 446 acres of intertidal wildlife habitat resources on

Whiskey and Timbalier Islands.

5.7.1.5.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wildlife and habitat

resources of implementing Alternative 3 would be similar to those described for the

Whiskey and Timbalier Islands components of Alternative 5 (NER Plan).

Alternative 3 would restore a net total of 1,851 acres of wildlife habitat resources

with 0 net acres dune, 400 net acres supratidal, and 1,451 net acres of intertidal

wildlife habitat resources over the 50-year period of analysis. In addition,

Alternative 3 would restore Whiskey and Timbalier Islands to their minimal

geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially wildlife habitat resources, to open water habitat.

5.7.1.5.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan) including the synergistic

interaction of the impacts of Alternative 3 restoring a net total of 1,851 acres with

1,778 AAHUs of wildlife and habitat resources on Whiskey and Timbalier Islands.

Alternative 3 would also, restore the minimal geomorphologic form to Whiskey and

Timbalier Islands that would, consistent with Stone (2005), enable these barrier

islands to maintain their function of absorbing wave energy during storms and fairweather conditions and provide some undetermined level of storm surge protection

and reduction of wave potential for the Terrebonne Basin estuarine wetland

vegetation resources. These incremental impacts would be in addition to similar

impacts for other barrier island restoration efforts across the Louisiana coastal area

by other Federal, State, and local barrier island restoration efforts.

5.7.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) /Timbalier (Plan E)

5.7.1.6.1 Direct

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Compared to the No Action Alternative, direct impacts to wildlife and habitat

resources of implementing Alternative 4 would be similar to those described for the

Whiskey, Trinity and Timbalier Islands component of Alternative 5 (NER Plan),

including initial restoration of a total 5,051 acres with 2,406 AAHUs with 409 acres

of dune, 3,632 acres of supratidal, 1,010 acres of intertidal wildlife habitat resources

on Whiskey, Trinity and Timbalier Islands.

5.7.1.6.2 Indirect

Compared to the No-Action Alternative, indirect impacts to wildlife and habitat

resources of implementing Alternative 4 would be similar to those described for the

Whiskey, Trinity and Timbalier Islands components of Alternative 5 (NER Plan).

Alternative 4 would restore a net total of 2,140 acres of wildlife habitat resources

with 0 net acres dune, 490 net acres supratidal, and 2,140 net acres of intertidal

wildlife habitat resources over the 50-year period of analysis. In addition,

Alternative 4 would restore Whiskey, Trinity and Timbalier Islands to their

minimal geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially wildlife habitat resources, to open water habitat.

5.7.1.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey, Trinity

and Timbalier Islands components of Alternative 5 (NER Plan) including the

synergistic interaction of the impacts of Alternative 4 restoring a net total of 2,140

acres with 2,406 AAHUs of wildlife and habitat resources on Whiskey, Trinity and

Timbalier Islands.

Alternative 4 would also, restore the minimal geomorphologic form to Whiskey,

Trinity and Timbalier Islands that would, consistent with Stone (2005), enable

these barrier islands to maintain their function of absorbing wave energy during

storms and fair-weather conditions and provide some undetermined level of storm

surge protection and reduction of wave potential for the Terrebonne Basin estuarine

wetland vegetation resources. These incremental impacts would be in addition to

similar impacts for other barrier island restoration efforts across the Louisiana

coastal area by other Federal, State, and local barrier island restoration efforts

5.8 AQUATIC RESOURCES

5.8.1 Benthic

5.8.1.1 No Action Alternative (Future without Project Conditions)

5.8.1.1.1 Direct

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The No Action Alternative, not implementing the LCA TBBSR Study, would have

no direct impacts on benthic resources and would result in the persistence of

existing conditions.

5.8.1.1.2 Indirect

The No Action Alternative would result in the conversion of approximately 3,220

acres of existing Terrebonne Basin barrier island beach, dune and marsh habitats

to water bottoms. Conversion of existing barrier island beach, dune and marsh

habitat to water bottom habitat would include degradation and loss of important

and essential fish and wildlife habitats used for shelter, nesting, feeding, roosting,

cover, nursery, and other life requirements; reduction in productivity; degradation

and loss of EFH, especially transitional habitat between estuarine and marine

environments; degradation and loss of stopover habitat for migrating neotropic

birds; and increased inter- and intra-specific competition between resident and

migratory fish and wildlife species for decreasing coastal barrier island resources.

The loss of the Terrebonne Basin barrier shoreline system would result in higher

wave energy levels and associated shoreline erosion to the adjacent Terrebonne

Basin estuarine bays (Stone and McBride 1998, Stone et al 2003, and Stone et al.

2005). Some unknown portions of the adjacent estuarine systems, along with their

various habitat resources, would be transformed into shallow open water habitat.

Although conversion of 3,220 acres of existing barrier habitat and an unknown

acreage of adjacent estuarine habitats to water bottoms would provide additional

habitat for benthic organisms, the conversion would decrease available nutrients

and detritus and result in the conversion of primarily estuarine-dependent benthic

species assemblages to more marine-dominated (in the case of the barrier islands)

and open water benthic species assemblages.

5.8.1.1.3 Cumulative

Cumulative impacts to benthic resources would be the synergistic effect of the NoAction Alternative of converting 3,220 acres of existing Terrebonne Basin barrier

island habitats to water bottoms, along with the additive combination of

approximately 10% of Louisianas remaining coastal wetlands being converted to

water bottoms at a rate of 6,600 acres per year over the next 50 years, resulting in

an additional net loss of 328,000 acres by 2050 (Barras et al. 2003). This

widespread habitat conversion would decrease available nutrients and detritus and

result in the conversion of primarily estuarine-dependent benthic species

assemblages to more marine-dominated (in the case of the barrier islands) and open

water benthic species assemblages.

These impacts would be offset, to some degree, by the additive combination of

impacts and benefits for overall acres of water bottoms impacted by other Federal,

State, local, and private restoration efforts. Coastal water bottoms in Louisiana

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have been impacted, to some degree, by efforts under the CWPPRA program, and

the beneficial use of dredged material requirements under Section 307 of the

Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

These impacts would be offset, to some degree, by the synergistic additive

combination of impacts and benefits of coastal barrier island restoration by other

Federal, State, local, and private restoration efforts that would restore barrier

island resources and, in turn, protect adjacent estuarine systems and their

associated benthic resources from converting to shallow open water habitats.

Coastal barrier islands in Louisiana have been restored, to some degree, by efforts

under the CWPPRA program, and the beneficial use of dredged material

requirements under Section 307 of the Coastal Zone Management Act of 1972, 16

U.S.C. 1451 et. seq..

5.8.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

Compared to the No Action Alternative, direct impacts of implementing Alternative

5 (NER Plan) to benthic organisms would primarily occur during the dredging of fill

material from offshore borrow areas and placement of borrow material within the

Study Area. Construction of the terminal groin on Raccoon Island would directly

impact a total of 2 acres of Gulf of Mexico water bottoms

Initial construction would directly impact a total of 2,498 acres of borrow site water

bottoms and benthic organisms utilizing these areas including: 744 acres at the

South Pelto-6; 1,187 acres at Ship Shoal, 31 acres at Whiskey 3a (12 ft depth); 366

acres at Whiskey 3a (20 ft depth); 87 acres at New Cut, and 83 acres at Raccoon

Island. Renourishment would directly impact a total of 1,222 acres of borrow site

water bottoms and benthic organisms utilizing these areas including 1,196 acres at

Ship Shoal and 26 acres at South Pelto.

A total of 3,283 acres of existing water bottoms would be converted to beach, dune

and marsh barrier habitats during initial construction. Renourishment would

impact 1,633 acres of water bottoms and associated benthic organisms.

Dredging and placement of borrow material, as well as placement of rock over 2

acres for construction of the terminal groin on Raccoon Island, could destroy any

slow-moving or sessile benthic organisms found within the borrow areas, within the

barrier island restoration/creation areas, or within the footprint of the terminal

groin at Raccoon Island. However, more mobile benthic species would likely be

displaced to more suitable habitats.

Special precautions would be taken in the design and placement of borrow material

to minimize disturbance to the benthic communities and maximize their potential

for recolonization and recovery. Examples of measures to avoid and minimize

potential adverse impacts to benthic resources include borrow area size, spacing,

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limiting cut depths and dredging frequency to maximize recovery of the benthic

community.

Borrow Area Impacts

Potential impacts to benthic communities from mining Ship Shoal were reported in

Stone et al. (2009) with findings later published in Dubois et al. (2009), Grippo et al.

(2009), and Grippo et al. (2010). Summaries of findings from Stone et al. (2009) are

were presented in Section 1.5.1.9. These studies provided baseline information to

better understand the ecological services provided by Ship Shoal and to predict

disturbance caused by sand mining.

Dubois et al. (2009) predict that the benthic macrofauna at Ship Shoal would be

strongly affected and slow to recover from sand mining. Sand mining would cause

a shift in species dominance to disturbance specialists that are fast-growing,

small, have rapid reproduction rates and body growth which enables them to

colonize disturbed habitats. This could lead to a reduction in biomass which would

indirectly impact higher trophic levels (Dubois et al. (2009).

Physical changes to Ship Shoal, such as water depth and mean particle size, and

turbidity resulting from dredging activities would also likely affect the benthic

community composition and influence primary production. Grippo et al (2009)

suggest that benthic microalgae may have higher biomass than phytoplankton on

Ship Shoal and contribute significantly to the shoals food web. Changes in primary

production (impact to the microalgae community) and particle size could reduce the

benthic community biomass and alter the species composition which could affect

higher trophic levels. Furthermore, Grippo et al. (2009) suggest that the benthic

larvae spawned on Ship Shoal could help to recolonize the nearby areas impacted by

the seasonal hypoxic zone. In addition, Ship Shoal offers a hypoxia refuge for

benthic species as well as an important foraging ground for fish and large

crustaceans, especially blue crabs that feed on the benthic invertebrates (Grippo et

al. 2009).

Grippo et al. (2009) conclude that the effects of sand mining activities on Ship Shoal

benthos would likely last for months to years and effects may extend to shoaldependent nekton by food web interactions. These authors conclude that Ship Shoal

and other sandy shoals offshore of Louisiana play a vital ecological role in the

ecology of the northern Gulf of Mexico and offer more than mineral resources.

Borrow Material Placement Impacts

Placement of borrow material for barrier shoreline restoration/creation would

directly impact and destroy any slow-moving or sessile benthic organisms found

within the intertidal footprints of the restoration sites. More mobile benthic species

utilizing these areas would likely be displaced to more suitable habitats. Other

direct impacts to the benthos would be localized and confined to construction areas

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such as fill templates and access channels. However, the prolific nature of the

benthic community is expected to recolonize within 1-2 years following construction.

5.8.1.2.1 Indirect

Compared to the No Action Alternative, primarily indirect impacts of implementing

Alternative 5 (NER Plan) would be a net increase of 2,118 acres of intertidal barrier

habitats used not only by benthic organisms but also by various fish and wildlife

species for shelter, nesting, feeding, roosting, cover, nursery, and other life

requirements; increased vegetation growth and productivity; and reduced inter- and

intra-specific species competition between resident and non-resident fish and

wildlife species for limited coastal vegetation. Alternative 5 (NER Plan) would

restore and rehabilitate dune, supratidal and intertidal vegetated coastal barrier

habitats; reduce conversion of these habitats to open water habitat; and provide

higher quality EFH, especially nursery habitat, for several species, including brown

and white shrimp, and blue crab. Vegetative plantings would contribute to reestablishment of a variety of wetland species that would further aid in sediment

trapping. Vegetative productivity would likely increase due to increased vegetated

acres of barrier habitats. Important stopover habitats used by migrating

neotropical birds would be restored and sustained for future use over the 50-year

period of analysis. Compared to the No Action Alternative, implementing

Alternative 5 (NER Plan) would delay the conversion of barrier habitats to open

water habitats over the 50-year period of analysis.

Borrow Area Impacts

Indirect impacts to benthic organisms caused by implementing Alternative 5 (NER

Plan) are presented above as direct and indirect impacts involve food web dynamics

and shifts of benthic species composition resulting from physical disturbance of

dredging as well as the environmental changes that follow such as changes in water

depths, turbidity, and sediment characteristics.

Placement Impacts

Indirect impacts to benthic organisms would primarily be related to dredging and

placement of borrow material for barrier shoreline restoration/creation and

renourishment and placement of stone for creation of the terminal groin at Raccoon

Island. Construction of the terminal groin at Raccoon Island would result in

approximately 2 acres of water bottoms no longer available for use by benthic

organisms.

Short-term disturbance to benthic species during dredging and placement would

likely occur including: increased turbidity, temperature and biological oxygen

demand (BOD); and decreased dissolved oxygen due to hydraulic dredging, marsh

creation, and placement of shoreline protection activities. Some smothering of

benthic organisms may also occur from the resettlement of the dredge plume, but

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these impacts would be minimized through the use of silt curtains or other

construction measures to minimize dredging impacts. However, indirect impacts

would be generally localized and temporary. Waters would return to ambient

conditions following construction.

Dredging and placement activities could also cause temporary habitat degradation

to existing water bottoms used by benthos for various life requirements. Any such

impacts would initially cause increased inter- and intra-specific competition

between various benthic species for nearby available habitat resources. There could

also be a shift in species composition to those benthic species more tolerant of

disturbance. However, any such impacts would be temporary as benthos would

likely quickly re-colonize areas disturbed by dredging activities.

Actions taken to reduce potential impacts during construction could include the use

of silt curtains and retention dikes to minimize the effects of runoff, overland flow,

and sediment movement and erosion into adjacent waterways and marshes. These

measures could also help to restrict the extent of increases in turbidity and

suspended particulates to the immediate construction area.

Transitional barrier habitats restored by Alternative 5 (NER Plan) would indirectly

benefit benthic resources by providing increased dissolved organic compounds and

detritus that would, in turn, provide food and energy resources for benthic

organisms. This would eventually increase local epifauna which, in turn, would

help reduce turbidity, regenerate ammonia and phosphorous, and serve as

important sources of food for birds, nekton, and people (Day et al. 1989).

Other Indirect Impacts

Dredging activities, especially at Ship Shoal, could potentially alter wave dynamics,

thereby changing onshore storm-wave impacts, possibly leading to greater shoreline

erosion. However, Stone et al. (2004) indicates that removal of Ship Shoal sands for

barrier/coastal restoration efforts would not significantly influence wave conditions

in the nearshore because the expected increase in wave energy is limited to the

leeward flank of the shoal. For near-shore borrow areas, proposed borrow sites

would be designed to minimize the potential to alter wave dynamics (including

sufficient distance from the existing shoreline).

Other Indirect Impacts

Other indirect impacts could include: marine organisms that presently utilize the

gulf bottom substrates (especially benthos) would have to adapt to changes in gulf

bottom topography; restoration construction activities could cause short-term

disruption of commercial and recreational fishing; and alteration of gulf water

bottoms may change littoral drift dynamics; creation of depressions, furrows, and

pits could impact recolonization by the benthic community (Nairn et al 2004). The

primary concern is the potential for ridge and shoal type features to deflate or be

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smoothed out where borrow deposits are accessed on an ongoing basis. This could

lead to large-scale impacts to biological communities (Nairn et al. 2004). However,

Stone et al. (2004) indicates that removal of Ship Shoal sands for barrier/coastal

restoration efforts would not significantly influence wave conditions in the

nearshore because the expected increase in wave energy is limited to the leeward

flank of the shoal.

In addition, the MMS, International Activities and Marine Minerals Division is

charged with management of Federal Outer Continental Shelf (OCS) sand and

gravel resources that would be used for beach nourishment to repair storm damage

and protect against sea-level rise. To reduce potential environmental damage

associated with long-term and large-scale use of these resources, a project was

funded by MMS to design a comprehensive physical and biological monitoring

program for sand-mining activities.

Alternative 5 (NER Plan) would restore Whiskey, Raccoon, Trinity and Timbalier

Islands to their minimal geomorphologic form which would contribute to their

ecological functions of preventing conversion of the adjacent Terrebonne Basin

estuarine system to open water habitat.

Implementing Alternative 5 (NER Plan) would restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.8.1.2.2 Cumulative

Cumulative impacts of implementing Alternative 5 (NER Plan) on benthic resources

would include dredging impacts to a total of 3,720 acres of water bottoms (2,498

acres initially; 1,222 acres for renourishment) and placement of borrow material for

barrier island restoration over a total of 4,884 acres (3,283 acres initially; 1,601

acres renourishment) in synergistic combination with other impacts and benefits to

benthic resources for overall net acres of barrier shorelines restored by other

Federal, State, local, and private restoration efforts.

5.8.1.3 Alternative 11: Whiskey (Plan C with renourishment)

5.8.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to benthic organisms caused

by implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 10,340,701 cy of sediments from a total of 535 acres of borrow site water

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bottoms including: 487 acres at Ship Shoal, and 48 acres at Whiskey Area 3a.

Renourishment would remove a total of 16,599,548 cy of borrow material from a

total of 859 acres at Ship Shoal; with 9,413,143 cy removed from 487 acres at TY20

and 7,186,405 cy from 372 acres at TY40.

A total of 469 acres of existing water bottoms would be converted to beach, dune

and marsh barrier habitats during initial construction. Renourishment would

impact 823 acres of water bottoms and associated benthic organisms.

5.8.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including restoring 363 net acres of

intertidal habitat suitable for use by benthic and other fish and wildlife organisms,

over the 50-year period of analysis. In addition, Alternative 11 would restore

Whiskey Island to its minimal geomorphologic form which would contribute to its

ecological function of preventing conversion of the adjacent Terrebonne Basin

estuarine system to open water habitat.

5.8.1.3.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres of barrier habitats

suitable for benthic and other fish and wildlife organisms on Whiskey Island.

Alternative 11 would also, restore the minimal geomorphologic form to Whiskey

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.8.1.4 Alternative 2: Timbalier (Plan E)

5.8.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to benthic organisms caused

by implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 25,214,803 cy of sediments from a total of 1,375 acres of borrow site water

bottoms including: 613 acres at South Pelto  6 and 762 acres at Whiskey  3 (beach

and marsh). Renourshiment at TY30 would remove a total of 531,329 cy of borrow

material from, 26 acres at South Pelto  6 borrow site.

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A total of 1,675 acres of existing water bottoms would be converted to beach, dune

and marsh barrier habitats during initial construction. Renourishment would

impact 202 acres of water bottoms and associated benthic organisms.

5.8.1.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including restoring a net total of 1,088 net

acres of intertidal habitat suitable for use by benthic and other fish and wildlife

organisms, over the 50-year period of analysis. In addition, Alternative 2 would

restore Timbalier Island to its minimal geomorphologic form which would

contribute to its ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine system to open water habitat.

5.8.1.4.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 restoring a net total of 1,324 acres of barrier habitats

suitable for benthic and other fish and wildlife organisms on Timbalier Island.

Alternative 2 would also, restore the minimal geomorphologic form to Timbalier

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.8.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.8.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to benthic organisms caused

by implementing Alternative 3 would be similar to those described for the Whiskey

and Timbalier Islands components of Alternative 5 (NER Plan). Initial construction

would remove a total of 35,381,587 cy of borrow material from a total of 1,535 acres

of water bottoms in the offshore borrow areas including 487 acres at Ship Shoal; 613

acres at the South Pelto; 39 acres at Raccoon Island; and 396 acres at Whiskey

Area. Renourishment would remove a total of 17,130,877 cy from a total of 885

acres of water bottoms in offshore borrow areas including 27 acres at South Pelto

and 859 acres at Ship Shoal.

A total of 2,144 acres of existing water bottoms on Whiskey and Timbalier Islands

would be converted to beach, dune and marsh barrier habitats during initial

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construction. Renourishment would impact 1,025 acres of water bottoms and

associated benthic organisms.

5.8.1.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) including restoring a net total of

1,088 net acres of intertidal habitat suitable for use by benthic and other fish and

wildlife organisms, over the 50-year period of analysis. In addition, Alternative 3

would restore Whiskey and Timbalier Islands to their minimal geomorphologic form

which would contribute to their ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine system to open water habitat.

5.8.1.5.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan) including the synergistic

interaction of the impacts of Alternative 3 restoring a net total of 1,851 acres of

barrier habitats suitable for benthic and other fish and wildlife organisms on

Whiskey and Timbalier Islands. Alternative 3 would also, restore the minimal

geomorphologic form to Whiskey and Timbalier Islands that would, consistent with

Stone (2005), enable this barrier island to maintain its function of absorbing wave

energy during storms and fair-weather conditions and provide some undetermined

level of storm surge protection and reduction of wave potential for the Terrebonne

Basin estuarine wetland vegetation resources. These incremental impacts would be

in addition to similar impacts for other barrier island restoration efforts across the

Louisiana coastal area by other Federal, State, and local barrier island restoration

efforts.

5.8.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.8.1.6.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

4 would be similar to those described for the Whiskey, Trinity and Timbalier

Islands components of Alternative 5 (NER Plan). Initial construction would remove

a total of 65,985,063 cy of borrow material from a total of 1,998 acres of water

bottoms in the offshore borrow areas including 803 acres at Ship Shoal; 613 acres at

the South Pelto; 147 acres at New Cut; and 396 acres at Whiskey Area 3a.

Renourishment would remove a total of 21,440,567 cy from a total of 1,108 acres of

water bottoms in offshore borrow areas including 26 acres at South Pelto and 1082

acres at Ship Shoal.

A total of 2,729 acres of existing water bottoms on Whiskey, Trinity and Timbalier

Islands would be converted to beach, dune and marsh barrier habitats during initial

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construction. Renourishment would impact 1,562 acres of water bottoms and

associated benthic organisms.

5.8.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) including restoring a net

total of 1,650 net acres of intertidal habitat suitable for use by benthic and other

fish and wildlife organisms, over the 50-year period of analysis. In addition,

Alternative 3 would restore Timbalier Island to its minimal geomorphologic form

which would contribute to its ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine system to open water habitat.

5.8.1.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 restoring a net total of 2,140 acres of barrier habitats

suitable for benthic and other fish and wildlife organisms on Timbalier Island.

Alternative 2 would also, restore the minimal geomorphologic form to Timbalier

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.8.2 Plankton

5.8.2.1 No Action Alternative (Future without Project Conditions)

5.8.2.1.1 Direct

The No Action Alternative, not implementing the LCA TBBSR Study, would have

no direct impacts on benthic resources and would result in the persistence of

existing conditions.

5.8.2.1.2 Indirect

The No Action Alternative would result in continued degradation, fragmentation

and eventual conversion of approximately 3,220 acres of existing Terrebonne Basin

barrier island beach, dune and marsh habitats to marine-dominated water bottoms.

Plankton populations respond to changes in environmental conditions (Day et al.

1989). In particular, changes in salinity and nutrients can result in changes in

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plankton abundance and community structure. The conversion of the Terrebonne

Basin barrier shoreline to marine-dominated water bottoms would result in changes

to plankton abundance and community structure.

Human population growth throughout coastal Louisiana would likely result in

greater nutrient flux to coastal waterbodies, via an increase in sewerage discharges,

increased storm water runoff and increased use of fertilizers thereby impacting

nutrient flux in the system. Increased nutrient loads on coastal waterbodies could

cause further deterioration of water quality in eutrophic lakes and bays, at times

resulting in algal blooms, some of which could be noxious, thereby resulting in a

shift in community structure towards dominance by one or several species (Day et

al. 1989).

The loss of the Terrebonne Basin barrier shoreline system would result in higher

wave energy levels and associated shoreline erosion in the adjacent Terrebonne

Basin estuarine bays (Stone and McBride 1998, Stone et al 2003, and Stone et al.

2005). Some unknown portions of the existing adjacent estuarine systems would be

transformed into open water habitat. This loss of barrier habitats and estuarine

habitats would result in a decrease of available nutrients and detritus, which could

lead to the conversion of primarily estuarine-dependent plankton species

assemblages to more marine-dominant and open water plankton species

assemblages.

Conversion of existing barrier island beach, dune and marsh habitat to water

bottom habitat would also include degradation and loss of important and essential

fish and wildlife habitats used for shelter, nesting, feeding, roosting, cover, nursery,

and other life requirements; reduction in productivity; degradation and loss of EFH,

especially transitional habitat between estuarine and marine environments;

degradation and loss of stopover habitat for migrating neotropic birds; and

increased inter- and intra-specific competition between resident and migratory fish

and wildlife species for decreasing coastal barrier island resources.

In addition, loss of the Terrebonne Basin barrier shoreline system would indirectly

impact natural services (e.g., recreation, aesthetics and water purification) and

productivity (fish, shellfish and fur) resulting in undetermined potential economic

losses to Louisiana and the nation (after Van Heerden and DeRouen 1997). There

would also be unknown adverse indirect impacts to the culture and people of

Louisiana that utilize the various coastal resources dependent upon plankton foodweb.

5.8.2.1.3 Cumulative

Cumulative impacts to plankton resources would be the synergistic effect of the NoAction Alternative of converting 3,220 acres of existing Terrebonne Basin barrier

island habitats to marine-dominated water bottoms, along with the additive

combination of approximately 10% of Louisianas remaining coastal wetlands being

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converted to water bottoms at a rate of 6,600 acres per year over the next 50 years,

resulting in an additional net loss of 328,000 acres by 2050 (Barras et al. 2003).

These habitat conversions would result in changes to plankton abundance and

community structure. However, these impacts would be offset, to some degree, by

the additive combination of impacts and benefits for overall plankton resources

impacted by other Federal, State, local, and private restoration efforts. Coastal

plankton resources in Louisiana have been impacted, to some degree, by efforts

under the CWPPRA program, and the beneficial use of dredged material

requirements under Section 307 of the Coastal Zone Management Act of 1972, 16

U.S.C. 1451 et. seq.

5.8.2.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.8.2.2.1 Direct

Compared to the No Action Alternative, direct impacts to plankton resources of

implementing Alternative 5 (NER Plan) would be localized and short-term adverse

impacts, including mortality of some plankton populations, due to construction

activities of terminal groin at Raccoon Island, dredging activities at borrow sites as

well as placement of borrow for barrier island restoration. During initial

construction and re-nourishment a total of 1,1048 acres and 1,601 acres,

respectively, of water bottoms and fragmented barrier habitat would be converted to

beach, dune and marsh barrier habitats.

During construction, there would be a localized and short-term decrease in available

dissolved oxygen; an increase in turbidity, temperature and biological oxygen

demand (BOD). Following construction and dredging operations, the area would

return to ambient conditions and be re-colonized by plankton populations.

5.8.2.2.2 Indirect

Plankton serve several important roles in estuarine systems (Day et al. 1989). A

large number of benthic and nektonic adults spend part of their life in the

zooplankton, and as such the plankton stage influences the distribution and

abundance of adult populations. In addition, phytoplankton productivity is a major

source of primary food-energy for most estuarine ecosystems. Implementation of

Alternative 5 (NER Plan) would restore and re-nourishment a net total of 2,781

acres of transitional barrier habitats which would enhance and increase, to some

undetermined level, aquatic productivity and nutrient transformation functions.

An increase in the export of dissolved organic compounds and detritus from the

created and re-nourished barrier islands would benefit local plankton populations

by increasing the planktonic food web. Some local plankton populations would be

displaced due to construction of barrier islands. Barrier island restoration would

result in a long-term loss of shallow open water habitats available for plankton use.

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However, there is an abundance of shallow open water habitat throughout the

Study Area for use by planktonic resources.

5.8.2.2.3 Cumulative

Cumulative impacts to plankton resources of implementing Alternative 5 (NER

Plan) would primarily be associated with the incremental impacts of restoring a net

total of 2,781 acres of the Terrebonne Basin barrier shoreline system along with the

synergistic effect and combination of impacts and benefits for overall net acres of

barrier shoreline created, nourished, and protected by other Federal, State, local,

and private restoration efforts. Implementing Alternative 5 (NER Plan) would

synergistically interact with these other restoration projects to provide important

and essential energy inputs to the planktonic food web throughout coastal

Louisiana.

5.8.2.3 Alternative 11: Whiskey (Plan C with renourishment)

5.8.2.3.1 Direct

Compared to the No Action Alternative, direct impacts to plankton resources of

implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan). During initial construction and renourishment a total of 377 acres and 813 acres, respectively, of water bottoms and

fragmented barrier habitat would be converted to beach, dune and marsh barrier

habitats.

5.8.2.3.2 Indirect

Compared to the No-Action Alternative, indirect impacts to plankton resources of

implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan). Alternative 11 would restore and renourish a net total of 527 acres of transitional barrier habitats which would

enhance and increase, to some undetermined level, aquatic productivity and

nutrient transformation functions thereby benefiting local plankton populations.

5.8.2.3.3 Cumulative

Cumulative impacts of implementing Alternative 11 would be similar to those

described for the Whiskey Island component of Alternative 5 (NER Plan) including

the synergistic impacts of restoring a net total of 527 acres on Whiskey Island along

with the synergistic effect and combination of impacts and benefits for overall net

acres of barrier shoreline created, nourished, and protected by other Federal, State,

local, and private restoration efforts.

5.8.2.4 Alternative 2: Timbalier (Plan E)

5.8.2.4.1 Direct

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Compared to the No Action Alternative, direct impacts to plankton resources of

implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan). During initial construction and renourishment a total of 69 acres and 191 acres, respectively, of water bottoms and

fragmented barrier habitat would be converted to beach, dune and marsh barrier

habitats.

5.8.2.4.2 Indirect

Compared to the No-Action Alternative, indirect impacts to plankton resources of

implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan). Alternative 2 would restore and renourish a net total of 1,324 acres of transitional barrier habitats which would

enhance and increase, to some undetermined level, aquatic productivity and

nutrient transformation functions thereby benefiting local plankton populations.

5.8.2.4.3 Cumulative

Cumulative impacts of implementing Alternative 2 would be similar to those

described for the Timbalier Island component of Alternative 5 (NER Plan) including

the synergistic impacts of restoring a net total of 1,324 acres on Timbalier Island

along with the synergistic effect and combination of impacts and benefits for overall

net acres of barrier shoreline created, nourished, and protected by other Federal,

State, local, and private restoration efforts.

5.8.2.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.8.2.5.1 Direct

Compared to the No Action Alternative, direct impacts to plankton resources of

implementing Alternative 3 would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan). During initial

construction and re-nourishment a total of 446 acres and 1,004 acres, respectively,

of water bottoms and fragmented barrier habitat would be converted to beach, dune

and marsh barrier habitats.

5.8.2.5.2 Indirect

Compared to the No-Action Alternative, indirect impacts to plankton resources of

implementing Alternative 3 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan). Alternative 3 would restore and renourish a net total of 1,851 acres of transitional barrier habitats which would

enhance and increase, to some undetermined level, aquatic productivity and

nutrient transformation functions thereby benefiting local plankton populations.

5.8.2.5.3 Cumulative

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Cumulative impacts of implementing Alternative 3 would be similar to those

described for the Whiskey and Timbalier Islands components of Alternative 5 (NER

Plan) including the synergistic impacts of restoring a net total of 1,851 acres on

Whiskey and Timbalier Islands along with the synergistic effect and combination of

impacts and benefits for overall net acres of barrier shoreline created, nourished,

and protected by other Federal, State, local, and private restoration efforts.

5.8.2.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.8.2.6.1 Direct

Compared to the No Action Alternative, direct impacts to plankton resources of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and Timbalier Islands

components of Alternative 5 (NER Plan). During initial construction and re-nourishment a total

of 1,010 acres and 1,532 acres, respectively, of water bottoms and fragmented barrier habitat

would be converted to beach, dune and marsh barrier habitats.

5.8.2.6.2 Indirect

Compared to the No-Action Alternative, indirect impacts to plankton resources of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and Timbalier Islands

components of Alternative 5 (NER). Alternative 3 would restore and re-nourish a net total of

2,140 acres of transitional barrier habitats which would enhance and increase, to some

undetermined level, aquatic productivity and nutrient transformation functions thereby benefiting

local plankton populations.

5.8.2.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey, Trinity

and Timbalier Islands components of Alternative 5 (NER Plan) including the

synergistic impacts of restoring a net total of 2,140 acres on Whiskey, Trinity and

Timbalier Islands along with the synergistic effect and combination of impacts and

benefits for overall net acres of barrier shoreline created, nourished, and protected

by other Federal, State, local, and private restoration efforts.

5.9 FISHERIES

5.9.1.1 No Action Alternative (Future without Project Conditions)

5.9.1.1.1 Direct

The No Action Alternative, not implementing Terrebonne Basin barrier shoreline

restoration, would have no direct impacts on fisheries resources. Existing

conditions would persist.

5.9.1.1.2 Indirect

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The No Action Alternative would result in the conversion of approximately 3,220

acres of existing Terrebonne Basin barrier island transitional habitats to water

bottom habitats. The loss of the Terrebonne Basin barrier island system would

consequently result in higher wave energy levels and associated shoreline erosion in

the adjacent estuarine bays (Stone and McBride 1998, Stone et al 2003, and Stone

et al. 2005). Some unknown portions of the adjacent estuarine systems, along with

their wetland resources, would be transformed into open water habitat.

Conversion of existing barrier island beach, dune and marsh habitats to water

bottom habitat would include degradation and loss of important and essential fish

and wildlife habitats used for shelter, nesting, feeding, roosting, cover, nursery, and

other life requirements; reduction in productivity; degradation and loss of EFH,

especially transitional habitat between estuarine and marine environments;

degradation and loss of stopover habitat for migrating neotropic birds; and

increased inter- and intra-specific competition between resident and migratory fish

and wildlife species for decreasing coastal barrier island resources. Indirect impacts

to fisheries may result from the expected continuation of land loss and further loss

of habitat supportive of estuarine and marine fishery species. In the short-term,

land loss and predicted sea level changes are likely to increase open water habitats

available to marine species. Overall local fish populations could be impacted due to

the lack of nursery and spawning areas that would no longer be present in the

Study Area due to decreases in inner marsh and marsh edge, estuarine water

column and mud, sand, and shell substrate habitats.

In the long-term, as open water replaces barrier and estuarine wetland habitats

and the extent of marsh-to-water interface begins to decrease, fishery productivity

is likely to decline (Rozas and Reed 1993; Minello et al. 1994). This may already be

happening in the Terrebonne estuary. Browder et al. (1989) predicted that brown

shrimp catches in Barataria, Timbalier, and Terrebonne basins would peak around

the year 2000 and may fall to zero within 52 to 105 years.

Additional indirect impacts resulting from the loss of Terrebonne Basin barrier

islands and adjacent estuarine wetlands would include undetermined losses of

natural services (recreation, aesthetics and water purification) and productivity

(fish, shellfish and fur). This would result in an undetermined economic and

cultural loss to Louisiana and the Nation (Van Heerden and DeRouen, 1997).

5.9.1.1.3 Cumulative

The incremental cumulative impacts of the No Action Alternative would be the

conversion of 3,220 acres of Terrebonne Basin barrier island transitional habitats to

open water bottom habitats over the 50-year period of analysis. In addition, there

would be undetermined impacts to adjacent Terrebonne Basin estuarine wetland

resources due to the higher wave energy levels and associated shoreline erosion

(Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005) resulting from

Terrebonne Basin barrier island conversion to open water bottom habitat.

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Conversion of existing barrier island transitional habitats to water bottom habitat

would include degradation and eventual loss of important and essential fish habitat

thereby impacting fisheries populations to some unknown extent.

These impacts would be offset, to some degree, by the synergistic additive

combination of impacts and benefits of coastal barrier island restoration by other

Federal, State, local, and private restoration efforts that would restore barrier

island transitional habitats. Coastal barrier islands in Louisiana have been

restored, to some degree, by efforts under the CWPPRA program, and the beneficial

use of dredged material requirements under Section 307 of the Coastal Zone

Management Act of 1972, 16 U.S.C. 1451 et. seq. Essential fish habitat that

supports juvenile fish species will cease to exist in the Study Area once the barrier

shoreline and back barrier marsh is no longer present.

5.9.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.9.1.2.1 Direct

Compared to the No Action Alternative, direct impacts to fisheries resources of

implementing Alternative 5 (NER Plan) would be localized and short-term adverse

impacts due to construction activities of the terminal groin at Raccoon Island,

dredging activities at borrow sites and access canals, as well as placement of borrow

for barrier island restoration.

Initial construction would directly impact a total of 2,498 acres of borrow site water

bottoms including 744 acres at the South Pelto; 1,187 acres at Ship Shoal, 31 acres

at Whiskey 3a (12 ft depth); 366 acres at Whiskey 3a (20 ft depth); 87 acres at New

Cut, and 83 acres at Raccoon Island. Renourishment would directly impact a total

of 1,222 acres of borrow site water bottoms including 1,196 acres at Ship Shoal and

26 acres at South Pelto.

A total of 3,283 acres of existing water bottoms would be converted to barrier island

transitional habitats. Dredging and placement of borrow material could destroy any

slow-moving or sessile fisheries organisms found within the borrow areas and

within the barrier island restoration/creation areas. Sessile or slow moving fisheries

resources would also likely suffer some mortality or injury during placement of

rocks a the terminal groin at Raccoon Island. Construction activities would also

temporarily increase turbidity, temperatures and biological oxygen demand (BOD);

and decrease dissolved oxygen. However, following construction, displaced fisheries

resources would likely return to the Study Area.

5.9.1.2.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 5 (NER Plan) would be a net increase of 2,781 acres of transitional

barrier habitats with 2,883 AAHUs of important and essential transitional habitats

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used by fish and wildlife for shelter, nesting, feeding, roosting, cover, nursery, and

other life requirements; increased vegetation growth and productivity; and reduced

inter- and intra-specific species competition between resident and non-resident fish

and wildlife species for limited coastal vegetation.

Alternative 5 (NER Plan) would restore and rehabilitate dune, supratidal and

intertidal vegetated coastal barrier habitats; reduce conversion of these habitats to

open water habitat; and provide higher quality EFH, especially nursery habitat, for

several species, including brown and white shrimp, and blue crab. More nutrients

and detritus would be added to the food web, thereby increasing fish productivity

and providing a benefit to local fisheries. Recreational activities, such as fishing,

would also benefit from the increase in fish populations. Important stopover

habitats used by migrating neotropical birds would be restored and sustained for

future use over the 50-year period of analysis. Compared to the No Action

Alternative, implementing Alternative 5 (NER Plan) would delay the conversion of

transitional barrier habitats to open water habitats over the 50-year period of

analysis.

In addition, compared to the No Action Alternative, implementing Alternative 5

(NER Plan) would restore Raccoon, Timbalier, Trinity, and Whiskey Islands to their

minimal geormorphological form would result, consistent with Stone and McBride

(1998), Stone et al. (2003) and Stone et al. (2005), in the restored barrier islands

absorbing wave energy during storms and fair-weather conditions and providing

some storm surge protection. Restoring these four barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the adjacent estuarine system, especially wetlands resources, to open

water habitat.

The long-term sustainability of local fisheries would be more likely with

implementation of Alternative 5 (NER) than in the No-Action Alternative.

Increased productivity, as a result of increased vegetated barrier habitats would

provide indirect benefits to fisheries through an increase in the energy inputs into

the food web of the ecosystem in this area.

Louisiana has an extensive and productive oyster lease program, compared to other

states, providing more than 50% of the Nations oyster harvest (USACE 2004).

Implementation of Alternative 5 (NER Plan) would be expected to indirectly benefit

local oyster populations. Restoration of transitional habitats would provide

additional nutrients and detritus that would contribute to sustaining and

maintaining local oyster populations as compared to the No-Action Alternative.

Dredging on Ship Shoal could result in the alteration of sediment grain size and

potential reduction of infaunal populations which could have a cascading effect on

the distribution of certain demersal fish and other epibenthic predators at Ship

Shoal due to the depletion of food resources (MMS 2004). Depending on the

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recovery rate of the benthic communities in the dredged area and the extent of the

area dredged, this could have short-term or long-term effects (MMS 2004). However,

the proposed borrow areas are designed with consideration to avoid, minimize and

reduce potential long-term adverse impacts. It is anticipated that primary effects of

dredging would be short-term and related primarily to benthic organisms. It is

further anticipated that benthic organisms would recolonize the borrow areas

within one to two years.

5.9.1.2.3 Cumulative

Cumulative impacts to fisheries resources of implementing Alternative 5 (NER

Plan) would primarily be associated with the incremental impacts of restoring a net

total of 2,781 acres of the Terrebonne Basin barrier islands. In addition Alternative

5 (NER Plan) would restore the geomorphologic form to Raccoon, Whiskey, Trinity

and Timbalier Islands that would, consistent with Stone (2005), enable these

barrier islands to maintain their ecological function of providing important

transitional barrier habitat for fisheries resources. These impacts would be in

synergistic combination with the impacts and benefits for overall net acres of

transitional barrier islands created, nourished, and protected by other Federal,

State, local, and private restoration efforts.

5.9.1.3 Alternative 11: Whiskey (Plan C)

5.9.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to fisheries resources of

implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 10,340,701 cy of sediments from a total of 535 acres of borrow site water

bottoms including: 487 acres at Ship Shoal, and 48 acres at Whiskey Area 3a.

Renourishment would remove a total of 16,599,548 cy of borrow material from a

total of 859 acres at Ship Shoal; with 9,413,143 cy removed from 487 acres at TY20

and 7,186,405 cy from 372 acres at TY40.

Initial construction would cover approximately 469 acres of water bottoms and

fragmented barrier habitats. Renourishment with borrow material from Ship Shoal

would directly impact a total of 474 acres and 349 acres of water bottoms and

fragmented barrier habitats at TY20 and TY40, respectively

5.9.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including a net increase of 527 acres of

transitional barrier habitats with 678 AAHUs. In addition, Alternative 11 would

restore Whiskey Island to its minimal geomorphologic form which would contribute

to its ecological function of preventing conversion of the adjacent Terrebonne Basin

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estuarine wetlands to open water habitat thereby maintaining important

transitional estuarine habitat for fisheries resources.

5.9.1.3.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres with 678 AAHUs of

transitional barrier island habitat resources on Whiskey Island combined with

restoring the minimal geomorphologic form and ecological functions to Whiskey

Island that would in addition to similar impacts for other barrier island restoration

efforts across the Louisiana coastal area by other Federal, State, and local barrier

island restoration efforts.

5.9.1.4 Alternative 2: Timbalier (Plan E)

5.9.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to fisheries resources of

implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 25,214,803 cy of sediments from a total of 1,375 acres of borrow site water

bottoms including: 613 acres at South Pelto  6 and 762 acres at Whiskey  3 (beach

and marsh). Renourshiment at TY30 would remove a total of 531,329 cy of borrow

material from, 26 acres at South Pelto  6 borrow site.

Initial construction would cover approximately 1,675 acres of existing water

bottoms and fragmented barrier habitats. Renourishment at TY30, with borrow

material from South Pelto  6, would directly impact a total of 202 acres of water

bottoms and fragmented barrier habitats

5.9.1.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including a net increase of 1,324 acres of

transitional barrier habitats with 678 AAHUs. In addition, Alternative 2 would

restore Timbalier Island to its minimal geomorphologic form which would

contribute to its ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine wetlands to open water habitat thereby maintaining

important transitional estuarine habitat for fisheries resources.

5.9.1.4.3 Cumulative

Cumulative impacts would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 restoring a net total of 1324 acres with 1,100 AAHUs of

transitional barrier island habitat resources on Timbalier Island combined with

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restoring the minimal geomorphologic form and ecological functions to Whiskey

Island that would in addition to similar impacts for other barrier island restoration

efforts across the Louisiana coastal area by other Federal, State, and local barrier

island restoration efforts.

5.9.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.9.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to fisheries resources of

implementing Alternative 3 would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan). Initial construction

would remove a total of 35,381,587 cy of borrow material from a total of 2,786 acres

of water bottoms in the offshore borrow areas including 487 acres at Ship Shoal; 613

acres at the South Pelto; 39 acres at Raccoon Island; and 762 acres at Whiskey

Area. Renourishment would remove a total of 17,130,877 cy from a total of 885

acres of water bottoms in offshore borrow areas including 27 acres at South Pelto

and 859 acres at Ship Shoal.

Initial construction would cover a total of 3,752 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 474 acres at TY

20 and 349 acres at TY30 on Whiskey Island and 202 acres on Timbalier Island at

TY40.

5.9.1.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) including a net increase of 1,851

acres of transitional barrier habitats with 1,778 AAHUs. In addition, Alternative 3

would restore Whiskey and Timbalier Islands to their minimal geomorphologic form

which would contribute to their ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine wetlands to open water habitat thereby

maintaining important transitional estuarine habitat for fisheries resources.

5.9.1.5.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan) including the

synergistic interaction of the impacts of Alternative 3 restoring a net total of 1,851

acres with 1,778 AAHUs of transitional barrier island habitat resources on Whiskey

and Timbalier Islands combined with restoring the minimal geomorphologic form

and ecological functions to Whiskey and Timbalier Islands that would in addition to

similar impacts for other barrier island restoration efforts across the Louisiana

coastal area by other Federal, State, and local barrier island restoration efforts.

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5.9.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.9.1.6.1 Direct

Compared to the No Action Alternative, direct impacts of implementing Alternative

4 would be similar to those described for the Whiskey, Trinity and Timbalier

Islands components of Alternative 5 (NER Plan). Initial construction would remove

a total of 44,326,558 cy of borrow material from a total of 1,998 acres of water

bottoms in the offshore borrow areas including 814 acres at Ship Shoal; 613 acres at

the South Pelto; 39 acres at Raccoon Island; 147 acres at New Cut; and 762 acres at

Whiskey Area. Renourishment would remove a total of 21440567 cy from a total of

1,108 acres of water bottoms in offshore borrow areas including 26 acres at South

Pelto and 1,082 acres at Ship Shoal.

Initial construction would cover a total of 2,729 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 464 acres at TY

20 and 349 acres at TY40 on Whiskey Island; 528 acres on Trinity Island at TY 25;

and 191 acres on Timbalier Island at TY30.

5.9.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) including a net increase

of 2,140 acres of transitional barrier habitats with 2,406 AAHUs. In addition,

Alternative 4 would restore Whiskey, Trinity and Timbalier Islands to their

minimal geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine wetlands to open

water habitat thereby maintaining important transitional estuarine habitat for

fisheries resources.

5.9.1.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey, Trinity

and Timbalier Islands components of Alternative 5 (NER Plan) including the

synergistic interaction of the impacts of Alternative 4 restoring a net total of

2,140 acres with 2,406 AAHUs of transitional barrier island habitat resources on

Whiskey and Timbalier Islands combined with restoring the minimal

geomorphologic form and ecological functions to Whiskey and Timbalier Islands

that would in addition to similar impacts for other barrier island restoration efforts

across the Louisiana coastal area by other Federal, State, and local barrier island

restoration efforts.

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5.10 ESSENTIAL FISH HABITAT (EFH)

5.10.1.1 No Action Alternative (Future without Project Conditions)

5.10.1.1.1 Direct

The No Action Alternative, not implementing coastal barrier system restoration,

would have no direct impacts on EFH. Existing conditions would persist.

5.10.1.1.2 Indirect

The No Action Alternative would result in the conversion of approximately

3,220 acres of transitional barrier habitats from East Timbalier, Timbalier, Trinity,

East Island, Wine, Whiskey and Raccoon Islands to water bottom habitats over the

50 year period of analysis. The loss of the Terrebonne Basin barrier shoreline

system would result in higher wave energy levels and associated shoreline erosion

in the adjacent estuarine bays (Stone and McBride 1998, Stone et al 2003, and

Stone et al. 2005). Some unknown portions of the adjacent Terrebonne Basin

estuarine systems, along with their EFH resources  particularly estuarine marsh

habitat  a more productive category of EFH, would be transformed into open water

habitat, a less productive category of EFH.

Approximately 1,560 acres of existing intertidal back barrier marsh from the seven

barrier island system, a more productive category of EFH, would be converted to

marine-dominated water bottoms, a less productive EFH category. This loss would

continue to adversely impact essential spawning, nursery, nesting, and foraging

habitats for commercially and recreationally important species of finfish and

shellfish, as well as other aquatic organisms.

The loss of Terrebonne Basin barrier islands would adversely impact important

transitional habitat between barrier island and marine environments as well as

between estuarine and open water environments. This would result in the loss of

unique wildlife habitat (e.g., nursery, nesting, feeding, and roosting habitats); and

critical wintering habitat for the threatened piping plover. In addition, the

continued degradation and eventual loss of Terrebonne Basin barrier islands and

adjacent estuarine wetland resources would result in the loss of fish and wildlife

habitat which would likely increase competition between and within various fish

and wildlife species for diminishing habitat resources. The loss of vegetated

wetlands would also result in a loss in primary productivity.

Without implementation of the proposed barrier island restoration, the conversion

of barrier island categories of EFH, such as inner barrier marsh and barrier marsh

edge, to marine-dominated water column and mud, sand, or shell substrates is

expected to continue. Loss of the Terrebonne Basin barrier island system would

result in conversion of adjacent estuarine wetland EFH to water bottoms, water

column and mud, sand or shell substrates. This would result in a substantial

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decrease in the quality of EFH throughout the Study Area and reduce the areas

ability to support Federally-managed fisheries species.

Additional indirect impacts of loss of Terrebonne Basin barrier islands and adjacent

estuarine wetlands would be include undetermined losses of natural services

(recreation, aesthetics and water purification) and productivity (fish, shellfish and

fur). This would result in an undetermined economic and cultural loss to Louisiana

and the Nation (Van Heerden and DeRouen, 1997).

5.10.1.1.3 Cumulative

Louisiana has lost approximately 1,900 square miles (492,097 ha) of coastal

wetlands and barrier habitats, which are important EFH resources, since the 1930's

(Dunbar et al. 1992; Barras et al. 1994; Barras et al. 2003). Approximately 10

percent of Louisianas remaining coastal wetlands and barrier islands would be lost

at a rate of approximately 6,600 acres per year (2,672 ha per year) over the next 50

years, resulting in an additional net loss of 328,000 acres (132,794 ha) by 2050

(Barras et al. 2003). Land loss in the Study Area would likely continue at rates

similar to present resulting in the projected loss over all seven of the Terrebonne

barrier islands of about 3,220 acres. There would likely be a concomitant increase

in loss of adjacent estuarine wetlands with loss of the Terrebonne Basin barrier

island system. This projected loss would be in addition to the projected loss of

barrier islands and other coastal wetland resources throughout coastal Louisiana.

The LCA Study (USACE, 2004) estimated coastal Louisiana would continue to lose

land at a rate of approximately 6,600 acres per year over the next 50 years. Barrier

island loss, loss of adjacent estuarine wetlands, conversion of existing EFH, sea

level change, increased storm intensity, and other natural perturbations are

expected to contribute to a decrease in the diversity of EFH most supportive of

transitional estuarine habitat and barrier island habitat-dependent species.

5.10.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.10.1.2.1 Direct

Compared to the No Action Alternative, direct impacts to EFH resources of

implementing Alternative 5 (NER Plan) would be localized and due primarily to

construction activities of the terminal groin at Raccoon Island, dredging activities at

borrow sites, as well as placement of borrow for barrier island restoration.

Direct impacts of construction activities would result in the conversion of existing

shallow open water and fragmented barrier wetland EFH into more continuous

transitional emergent wetlands thereby increasing the quality of EFH within the

Raccoon, Whiskey, Trinity and Timbalier Islands.

Dredging would alter existing water bottom (hard sandy shoal EFH) within the

borrow areas. Initial construction would directly impact a total of 2,498 acres of

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borrow site water bottoms including 744 acres at the South Pelto; 1,187 acres at

Ship Shoal, 31 acres at Whiskey 3A (12 ft depth); 366 acres at Whiskey 3A (20 ft

depth); 87 acres at New Cut, and 83 acres at Raccoon Island. Renourishment would

directly impact a total of 1,222 acres of borrow site water bottoms (hard sandy shoal

EFH) including 1,196 acres at Ship Shoal and 26 acres at South Pelto. Dredging

impacts would be of short duration with water bottoms re-equilibrating and resettled with benthic fauna within one to two years.

Disruption of the Gulf of Mexico marine habitat EFH associated with borrow areas

would temporarily displace the fishery (e.g. dog snapper, lane snapper, red drum,

and shrimp) that inhabitants these areas of reefs and hard sand bottoms. Sessile of

slow moving benthic organisms within the borrow areas could be destroyed by

dredging activities. This would make the borrow areas less suitable for use by

benthic or fishery resources. However, these impacts would be temporary. Fishery

organisms would likely use the borrow areas shortly after dredging activities cease.

Benthic organisms would recolonize the borrow areas within one to two years.

A total of 3,283 acres of existing water bottoms and associated fragmented barrier

EFH (intertidal marsh) would be converted to transitional barrier island beach,

dune, and intertidal habitats. Alternative 5 (NER Plan) would restore a total of

1,315 acres of intertidal back barrier marsh, a more continuous and higher quality

EFH than existing open water and highly fragmented barrier habitat EFH. This

conversion of lower quality EFH to higher quality EFH would provide important

and essential transitional barrier habitats used by fish and wildlife for spawning,

nursery, foraging, cover, and other life requirements. Increased vegetation growth

and productivity would also reduce inter- and intra- specific competition between

resident and migratory fish and wildlife species for limited coastal vegetation

resources.

Dredging and placement activities would result in increased turbidity, coupled with

a slight increase in temperature and biological oxygen demand (BOD), and

decreased dissolved oxygen. These impacts would be temporary and localized.

The existing open water and highly fragmented intertidal marsh in the barrier

island restoration areas consist of fragmented emergent marsh, remnant and active

oyster reefs, and sand/shell/hard bottoms within the surrounding estuaries. Species

such as red drum; pink, brown, and white shrimp; stone crab; juvenile red snapper;

and juvenile Spanish mackerel would be temporarily impacted due to construction

of Alternative 5 (NER Plan) (see table 4-8). Although existing EFH would be

initially negatively impacted, such impacts would be offset by the restoration of

transitional barrier habitats, which are considered a higher-quality EFH.

5.10.1.2.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 5 (NER Plan) would be a net increase of 2,781 acres of transitional

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barrier habitats with 2,883 AAHUs of important and essential transitional barrier

habitats used by fish and wildlife for shelter, nesting, feeding, roosting, cover,

nursery, and other life requirements; increased vegetation growth and productivity;

and reduced inter- and intra-specific species competition between resident and nonresident fish and wildlife species for limited coastal vegetation.

Alternative 5 (NER Plan) would restore and rehabilitate dune, supratidal and

intertidal vegetated coastal barrier habitats; reduce conversion of these habitats to

open water habitat; and provide higher quality EFH, especially nursery habitat, for

several species, including brown and white shrimp, and blue crab. More nutrients

and detritus would be added to the food web, thereby increasing fish productivity

and providing a benefit to local fisheries. Recreational activities, such as fishing,

would also benefit from the increase in fish populations. Important stopover

habitats used by migrating neotropical birds would be restored and sustained for

future use over the 50-year period of analysis. Compared to the No Action

Alternative, implementing Alternative 5 (NER Plan) would delay the conversion of

transitional barrier habitats and associated higher quality EFH to lower quality

and more abundant open water habitats over the 50-year period of analysis.

Alternative 5 (NER Plan) would restore a net total of 2,118 acres of intertidal

habitats over the 50 year period of analysis. This would improve the quality of some

categories of EFH, including essential nursery habitats for many fishery species.

Alternative 5 (NER Plan) would not only increase the area extent of higher quality

EFH, but would also improve the quality of transitional barrier wetland habitats

used by fish for spawning, nursery, forage, cover, and other life requirements. An

increase in the acreage of transitional habitat between estuarine and marine

environments would result in decreased inter- and intra-specific competition

between resident and migratory fish species and would likely sustain a larger

variety and greater diversity of fishery species. Some of these fishery species serve

as prey to others; therefore, predator populations may be indirectly enhanced as

compared to the No-Action Alternative.

The long-term sustainability of local fisheries would be more likely with

implementation of Alternative 5 (NER Plan) than in the No-Action Alternative.

Increased productivity, as a result of increased vegetated barrier habitats would

provide indirect benefits to fisheries through an increase in the energy inputs into

the food web of the ecosystem in this area.

Louisiana has an extensive and productive oyster lease program, compared to other

states, providing more than 50% of the Nations oyster harvest (USACE 2004).

Implementation of Alternative 5 (NER Plan) would be expected to indirectly benefit

local oyster populations. Restoration of transitional habitats would provide

additional nutrients and detritus that would contribute to sustaining and

maintaining local oyster populations as compared to the No-Action Alternative.

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In addition, compared to the No Action Alternative, implementing Alternative 5

(NER Plan) would restore Raccoon, Timbalier, Trinity, and Whiskey Islands to their

minimal geormorphological form would result, consistent with Stone and McBride

(1998), Stone et al. (2003) and Stone et al. (2005), in the restored barrier islands

absorbing wave energy during storms and fair-weather conditions and providing

some storm surge protection. Restoring these four barrier islands to their

geomorphologic form would also contribute to their ecological function of preventing

conversion of the adjacent estuarine wetland EFH resources to open water EFH.

5.10.1.2.3 Cumulative

Cumulative impacts to EFH resources of implementing Alternative 5 (NER Plan)

would primarily be associated with the incremental impacts of restoring a net total

of 2,781 acres of the Terrebonne Basin barrier islands. Although there would be

impacts to marine water bottom EFH associated with dredging a total of 3,720 acres

of water bottoms for initial construction and re-nourishment, these impacts would

likely be of short duration and not significant. In addition Alternative 5 (NER Plan)

would restore the geomorphologic form to Raccoon, Whiskey, Trinity and Timbalier

Islands that would, consistent with Stone (2005), enable these barrier islands to

maintain their ecological function of providing important transitional barrier

habitat for fisheries resources. These impacts would be in synergistic combination

with the impacts and benefits for overall net acres of transitional barrier islands

created, nourished, and protected by other Federal, State, local, and private

restoration efforts. Cumulative impacts would be the synergistic effect with the

additive combination of impacts and benefits for overall net acres of barrier habitats

restored by other Federal, State, local, and private restoration efforts. Alternative 5

(NER Plan) would synergistically interact with those other projects to provide

higher quality EFH.

5.10.1.3 Alternative 11: Whiskey Plan C (w/ renourishment)

5.10.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to EFH resources of

implementing Alternative 11 would be similar to those described for the Whiskey

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 10,340,701 cy of sediments from a total of 535 acres of borrow site water

bottoms including: 487 acres at Ship Shoal, and 48 acres at Whiskey Area 3a.

Renourishment would remove a total of 16,599,548 cy of borrow material from a

total of 859 acres at Ship Shoal; with 9,413,143 cy removed from 487 acres at TY20

and 7,186,405 cy from 372 acres at TY40.

A total of 469 acres of existing water bottoms and associated fragmented barrier

EFH (intertidal marsh) would be converted to transitional barrier island beach,

dune, and intertidal habitats. Alternative 11 would restore a total of 377 acres of

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intertidal back barrier marsh, a more continuous and higher quality EFH than

existing open water and highly fragmented barrier habitat EFH.

5.10.1.3.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 11 would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including a net increase of 527 acres of

transitional barrier habitats with 678 AAHUs. In addition, Alternative 11 would

restore Whiskey Island to its minimal geomorphologic form which would contribute

to its ecological function of preventing conversion of the adjacent Terrebonne Basin

estuarine wetlands and associate EFH to open water habitat EFH thereby

maintaining important transitional estuarine habitat for fisheries resources.

Alternative 11 would restore a net total of 363 acres of intertidal habitats over the

50 year period of analysis.

5.10.1.3.3 Cumulative

Cumulative impacts to EFH resources of implementing Alternative 11 would be

similar to those described for the Whiskey Island component of Alternative 5 (NER

Plan) and would be primarily associated with the incremental impacts of restoring a

net total of 527 acres on Whiskey Island. Although there would be impacts to

marine water bottom EFH associated with dredging a total of 1,394 acres of water

bottoms for initial construction and re-nourishment, these impacts would likely be

of short duration and not significant. Cumulative impacts would be the synergistic

effect with the additive combination of impacts and benefits for overall net acres of

barrier habitats, and their associated EFH, restored by other Federal, State, local,

and private restoration efforts. Alternative 11 would work cooperatively with those

projects to provide higher quality EFH.

5.10.1.4 Alternative 2: Timbalier (Plan E)

5.10.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to EFH resources of

implementing Alternative 2 would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan). Initial construction would remove a

total of 25,214,803 cy of sediments from a total of 1,375 acres of borrow site water

bottoms including: 613 acres at South Pelto  6 and 762 acres at Whiskey  3 (beach

and marsh). Renourshiment at TY30 would remove a total of 531,329 cy of borrow

material from, 26 acres at South Pelto  6 borrow site.

Initial construction would cover approximately 1,675 acres of existing water

bottoms and fragmented barrier habitats. Renourishment at TY30, with borrow

material from South Pelto  6, would directly impact a total of 202 acres of water

bottoms and fragmented barrier habitats.

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A total of 1,675 acres of existing water bottoms and associated fragmented barrier

EFH (intertidal marsh) would be converted to transitional barrier island beach,

dune, and intertidal habitats. Alternative 2 would restore a total of 564 acres of

intertidal back barrier marsh, a more continuous and higher quality EFH than

existing open water and highly fragmented barrier habitat EFH.

5.10.1.4.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 2 would be similar to those described for the Timbalier Island

component of Alternative 5 (NER Plan) including a net increase of 1,324 acres of

transitional barrier habitats with 1,100 AAHUs. In addition, Alternative 2 would

restore Timbalier Island to its minimal geomorphologic form which would

contribute to its ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine wetlands and associate EFH to open water habitat

EFH thereby maintaining important transitional estuarine habitat for fisheries

resources. Alternative 2 would restore a net total of 1,088 acres of intertidal

habitats over the 50 year period of analysis.

5.10.1.4.3 Cumulative

Cumulative impacts to EFH resources of implementing Alternative 2 would be

similar to those described for the Timbalier Island component of Alternative 5 (NER

Plan) and would be primarily associated with the incremental impacts of restoring a

net total of 1,324 acres on Timbalier Island. Although there would be impacts to

marine water bottom EFH associated with dredging a total of 1,401 acres of water

bottoms for initial construction and re-nourishment, these impacts would likely be

of short duration and not significant. Cumulative impacts would be the synergistic

effect with the additive combination of impacts and benefits for overall net acres of

barrier habitats, and their associated EFH, restored by other Federal, State, local,

and private restoration efforts. Alternative 2 would work cooperatively with those

projects to provide higher quality EFH.

5.10.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.10.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to EFH resources of

implementing Alternative 3 would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan). Initial construction

would remove a total of 35,381,587 cy of borrow material from a total of 2,786 acres

of water bottoms in the offshore borrow areas including 487 acres at Ship Shoal; 613

acres at the South Pelto; 39 acres at Raccoon Island; and 762 acres at Whiskey

Area. Renourishment would remove a total of 17,130,877 cy from a total of 885

acres of water bottoms in offshore borrow areas including 27 acres at South Pelto

and 859 acres at Ship Shoal.

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Initial construction would cover a total of 3,752 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 474 acres at TY

20 and 349 acres at TY30 on Whiskey Island and 202 acres on Timbalier Island at

TY40.

5.10.1.5.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 3 would be similar to those described for the Whiskey and Timbalier

Islands components of Alternative 5 (NER Plan) including a net increase of 1,851

acres of transitional barrier habitats with 1,778 AAHUs. In addition, Alternative 3

would restore Whiskey and Timbalier Islands to their minimal geomorphologic form

which would contribute to their ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine wetlands and associated EFH to open water

habitat EFH thereby maintaining important transitional estuarine habitat for

fisheries resources. Alternative 3 would restore a net total of 1,451 acres of

intertidal habitats over the 50 year period of analysis.

5.10.1.5.3 Cumulative

Cumulative impacts to EFH resources of implementing Alternative 3 would be

similar to those described for the Whiskey and Timbalier Islands components of

Alternative 5 (NER Plan) and would be primarily associated with the incremental

impacts of restoring a net total of 1,851 acres on Whiskey and Timbalier Islands.

Although there would be impacts to marine water bottom EFH associated with

dredging a total of 3,671 acres of water bottoms for initial construction and renourishment, these impacts would likely be of short duration and not significant.

Cumulative impacts would be the synergistic effect with the additive combination of

impacts and benefits for overall net acres of barrier habitats, and their associated

EFH, restored by other Federal, State, local, and private restoration efforts.

Alternative 3 would work cooperatively with those projects to provide higher quality

EFH.

5.10.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.10.1.6.1 Direct

Compared to the No Action Alternative, direct impacts to EFH resources of

implementing Alternative 3 would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan). Initial construction

would remove a total of 44,326,558 cy of borrow material from a total of 1,998 acres

of water bottoms in the offshore borrow areas including 814 acres at Ship Shoal; 613

acres at the South Pelto; 39 acres at Raccoon Island; 147 acres at New Cut; and 762

acres at Whiskey Area 3a. Renourishment would remove a total of 21440567 cy

from a total of 1,108 acres of water bottoms in offshore borrow areas including 26

acres at South Pelto and 1082 acres at Ship Shoal.

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Initial construction would cover a total of 2,729 acres of water bottoms and existing

fragmented barrier habitats. Renourishment would directly cover 464 acres at TY

20 and 349 acres at TY40 on Whiskey Island; 528 acres on Trinity Island at TY 25;

and 191 acres on Timbalier Island at TY30.

5.10.1.6.2 Indirect

Compared to the No Action Alternative, indirect impacts of implementing

Alternative 4 would be similar to those described for the Whiskey, Trinity and

Timbalier Islands components of Alternative 5 (NER Plan) including a net increase

of 2,140 acres of transitional barrier habitats with 2,406 AAHUs. In addition,

Alternative 4 would restore Whiskey, Trinity and Timbalier Islands to their

minimal geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine wetlands and

associated EFH to open water habitat EFH thereby maintaining important

transitional estuarine habitat for fisheries resources. Alternative 4 would restore a

net total of 1,650 acres of intertidal habitats over the 50 year period of analysis.

5.10.1.6.3 Cumulative

Cumulative impacts to EFH resources of implementing Alternative 4 would be

similar to those described for the Whiskey, Trinity and Timbalier Islands

components of Alternative 5 (NER Plan) and would be primarily associated with the

incremental impacts of restoring a net total of 2,140 acres on Whiskey, Trinity and

Timbalier Islands. Although there would be impacts to marine water bottom EFH

associated with dredging a total of 3,106 acres of water bottoms for initial

construction and re-nourishment, these impacts would likely be of short duration

and not significant. Cumulative impacts would be the synergistic effect with the

additive combination of impacts and benefits for overall net acres of barrier

habitats, and their associated EFH, restored by other Federal, State, local, and

private restoration efforts. Alternative 3 would work cooperatively with those

projects to provide higher quality EFH.

5.11 THREATENED AND ENDANGERED SPECIES

5.11.1.1 No Action Alternative (Future without Project Conditions)

5.11.1.1.1 Direct

The No Action Alternative, not implementing Terrebonne Basin barrier shoreline

restoration, would have no direct impacts on listed (endangered or threatened)

species or their critical habitat. Existing conditions would persist; listed species

would likely continue to be subject to institutional recognition and further

regulations and Federal management.

5.11.1.1.2 Indirect

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Without any action, approximately 3,220 acres of existing barrier island

transitional habitats from the seven island Terrebonne Basin barrier system (East

Timbalier, Timbalier, Trinity, East Island, Wine, Whiskey and Raccoon Island)

would continue to degrade, fragment and eventually convert into marine-dominated

open water bottoms. Loss of the Terrebonne Basin barrier island system would

result in higher wave energy levels and associated shoreline erosion in the adjacent

estuarine bays (Stone and McBride 1998, Stone et al 2003, and Stone et al. 2005). If

the Terrebonne Basin barrier island system is not restored, the adjacent estuarine

wetlands would also continue to be converted into open water habitat.

Indirect impacts of not implementing the Terrebonne Basin barrier island

restoration features would result in the continued degradation and loss of

designated critical wintering habitat and its primary constituents for the

threatened piping plover. Other listed species could also be adversely impacted by

the loss of the barrier islands including: Gulf sturgeon, green sea turtle, hawksbill

sea turtle, Kemps Ridley sea turtle, leatherback sea turtle, loggerhead sea turtle,

and the West Indian manatee. However, the piping plover and sea turtles would

most likely be impacted to the greatest extent, as these species utilize the rapidly

deteriorating barrier systems.

Loss of the Terrebonne Basin barrier islands and the concomitant conversion of

adjacent estuarine transitional wetlands would adversely affect not only listed

species but also other fish and wildlife species that utilize the Study Area such as

colonial nesting water birds, shorebirds, and the brown pelican. Indirect impacts

would include conversion of higher quality EFH (back barrier and estuarine marsh

habitat) to lower quality EFH (open water habitat); loss of unique fish and wildlife

habitats used for nursery, nesting, feeding, and roosting habitats and other life

requirements. The continued degradation and eventual loss of barrier and estuarine

wetland resources would result in the loss of fish and wildlife habitat which would

likely increase competition between and within various fish and wildlife species for

diminishing habitat resources. The loss of vegetated wetlands would also result in

a loss in primary productivity. In the long-term, as marine-influenced open water

replaces transitional barrier island wildlife habitats and shallow open water

replaces existing estuarine wildlife habitats, the extent of land-to-water interface

would decrease and wildlife productivity would also likely decline.

Van Heerden and DeRouen (1997) indicate the loss of Louisianas coastal wetlands,

including barrier island and barrier shorelines, was conservatively valued at

$1,000/hectare in terms of natural services (recreation, aesthetics and water

purification) and productivity (fish, shellfish and fur) resulting in the annual loss to

Louisiana and the nation exceeding $150 million every year. Van Heerden and

DeRouen father indicate that the people living in the Louisiana coastal zone, the

heart of Cajun culture, would have the greatest impact on the States economy;

hence, restoring the coast would therefore advance the economic development of the

State of Louisiana.

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5.11.1.1.3 Cumulative

The projected loss over all seven of the Terrebonne barrier islands of about 3,220

acres of barrier island transitional habitat by 2062 would be in synergistic

combination with an unknown area of adjacent existing Terrebonne Basin estuarine

habitats converting to open water habitat following the collapse of the Terrebonne

Basin barrier shoreline system. Existing barrier and estuarine transitional fish and

wildlife habitat would convert to marine dominated shallow open water thereby

causing fish and wildlife species to move to areas that better support their habitat

requirements. Listed species that would be primarily affected would be the piping

plover and sea turtles.

Impacts from the loss of the Terrebonne Basin barrier island system and adjacent

estuarine system would be in addition to the projected loss of fish and wildlife and

piping plover critical wintering habitat resources throughout coastal Louisiana and

the Nation. The LCA Study (USACE, 2004) estimated coastal Louisiana would

continue to lose land at a rate of approximately 6,600 acres per year over the next

50 years. Louisiana has lost approximately 1,900 square miles (492,097 ha) of

coastal wildlife habitat resources since the 1930's (Dunbar et al. 1992; Barras et al.

1994; Barras et al. 2003). Approximately 10 percent of Louisianas remaining

coastal wetlands would be lost at a rate of approximately 6,600 acres per year

(2,672 ha per year) over the next 50 years, resulting in an additional net loss of

328,000 acres (132,794 ha) by 2050 (Barras et al. 2003). Coastal barrier

transitional habitat loss and estuarine transitional habitat loss in Louisiana has

been addressed, to some degree, by efforts under the Coastal Wetlands Planning,

Protection and Restoration Act (CWPPRA) program, and the beneficial use of

dredged material requirements under Section 307 of the Coastal Zone Management

Act of 1972, 16 U.S.C. 1451 et. seq. area.

5.11.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.11.1.2.1 Direct

Compared to the No Action Alternative, direct impacts to listed species of

implementing Alternative 5 (NER Plan) would primarily result from initial

construction and re-nourishment construction activities related to placement of

borrow material on existing fragmented dune, supratidal, intertidal (gulfside and

bayside) and shallow open water habitats that would make these habitats

temporarily unavailable and could disrupt or displace listed species utilizing these

habitats. Direct impacts of implementing Alternative 5 (NER Plan) on listed species

is presented below. A Biological Assessment (Appendix A) and the USFWS

Biological Opinion (Appendix B) provide more detailed information.

Piping Plover Impacts

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Critical Habitat Impacts

Alternative 5 (NER Plan) would initially restore a total of 3,730 acres of piping

plover critical wintering habitat over the four barrier islands including: 619 acres

on Raccoon, 624 acres on Whiskey, 434 acres on Trinity, and 2053 acres on

Timbalier Island (see Biological Assessment, Appendix A). Beneficial impacts to

the piping plover and its critical habitat include restoration of critical wintering

habitat and prolonged life of barrier islands, as well as constructing a terminal

groin on Raccoon Island that would function to protect critical habitat. Much of the

existing barrier island system is sediment-starved, and the proposed action would

introduce sediment into the system that would be reworked and redistributed

through future storm events, thereby maintaining and/or enhancing the features of

critical wintering habitat (i.e. sand and mud flats) that are essential to piping

plover conservation.

Apart from the terminal groin on Raccoon Island, the project is not expected to alter

the natural longshore sediment transport mechanisms within the Isles Dernieres

and Timbalier Islands. Without the terminal groin, the sediment that moves off of

Raccoon Island to the west is lost to the shoals and buried by the mud stream from

the Atchafalaya. Therefore, the terminal groin on Raccoon Island will not starve

other islands in adjacent reaches.

Piping plover critical wintering habitat was assumed to be the unvegetated portion

of the dune, supratidal, and gulfward intertidal habitats (personal communication

Ms. Brigette Firmin, USFWS August, 2010). The intertidal habitats, such as the

beaches, mudflats, and sand flats, provide vital foraging grounds for the piping

plover. Unvegetated dune and supratidal habitats function as suitable roosting and

sheltering areas. The predicted critical habitat acres are provided in Tables 5-5

through 5-8.

Table 5-5. Predicted Critical Habitat Acreages for Raccoon Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY20 TY301 TY31 TY40 TY50

FWOP2 61 61 43 23 10 6 6 0 0

FWP3 61 680 295 348 339 183 276 139 133

Net4 0 619 253 325 329 178 270 139 133

1

Renourishment occurs at TY30

2

FWOP – Future Without Project (i.e. no action)

3

FWP – Future With Project

4

Net = FWP – FWOP

Table 5-6. Predicted Critical Habitat Acreages for Whiskey Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY201 TY21 TY30 TY401 TY41 TY50

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FWOP2 221 220 91 64 47 46 37 0 0 0

FWP3 221 843 236 223 127 615 212 89 464 118

Net4 0 624 146 159 80 569 174 89 464 118

1

Renourishment occurs at TY20 and TY40

2

FWOP – Future Without Project (i.e. no action)

3

FWP – Future With Project

4

Net = FWP – FWOP

Table 5-7. Predicted Critical Habitat Acreages for Trinity Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY20 TY251 TY26 TY30 TY40 TY50

FWOP2 158 149 110 60 10 6 6 3 0 0

FWP3 158 583 238 232 154 123 626 277 170 87

Net4 0 434 128 172 145 116 620 274 170 87

1

Renourishment occurs at TY25

2

FWOP – Future Without Project (i.e. no action)

3

FWP – Future With Project

4

Net = FWP – FWOP

Table 5-8. Predicted Critical Habitat Acreages for Timbalier Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY20 TY301 TY31 TY40 TY50

FWOP2 256 258 187 201 99 30 28 5 0

FWP3 256 2312 983 1152 1006 587 867 381 227

Net4 0 2053 796 952 907 557 839 376 227

1

Renourishment occurs at TY30

2

FWOP – Future Without Project (i.e. no action)

3

FWP – Future With Project

4

Net = FWP - FWOP

If Alternative 5 (NER Plan) were not constructed and the islands allowed to erode

at their current rate, the majority of existing critical habitat over these four islands

is expected to disappear by TY40. Alternative 5 (NER Plan) would substantially

increase the amount of critical habitat on the islands for each target year over the

50-year period of analysis.

Unavoidable short term impacts to piping plover critical wintering habitat would

primarily result from the placement of sediments onto existing beach and dune

habitats during construction and renourishment. These activities would smoother

existing populations of benthic prey species. Prey species smothered by dune and

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beach creating activities would re-colonize in these areas within two years once

construction activities cease (USFWS, 2010a). The critical habitat values do not

account for the required recovery time of these prey species. For example, there will

be approximately 867 acres of critical habitat on Timbalier Island immediately after

renourishment (i.e. TY31). However, the island will not reach optimal conditions for

the piping plover until TY33, once the benthic species have recovered.

Potential impacts that would occur to existing designated critical habitat would be

temporary, and would provide for the long-term maintenance and/or enhancement

of critical habitat within the Study Area. There would be no permanent impacts to

critical habitat that would change the ecological processes that maintain it.

However, because an entire island would be affected during a construction event,

and because adjacent islands may undergo construction within two years or less,

the ability of those islands to provide enough suitable foraging habitat to piping

plovers will likely be affected until all construction is completed (USFWS 2010a).

Based on these factors, it is the USACE determination that implementing

Alternative 5 (NER Plan) is likely to adversely affect the piping plover and its

critical habitat.

Species Impacts:

Under optimal conditions, impacts to piping plovers could be avoided by conducting

the proposed activities outside the wintering season. However, construction would

likely occur while plovers are present. Due to the magnitude of barrier island

erosion and land-loss rates, delaying construction until the non-wintering season

could result is considerable degradation to each barrier island foundation and thus

require significant increases in fill volume requirements.

Furthermore, delays would be extremely risky because the existing habitats would

be more vulnerable to hurricane forces. Therefore, the risks associated with

delaying the project are not justified based on the temporary nature of the

disturbance. Due to their mobility, piping plovers would be able to avoid areas of

temporary disturbance using the abundance of suitable foraging and roosting areas

adjacent to the Study Area. For example, East Island, which is a continuation of

Trinity Island, currently supports 272 acres of critical habitat. East Timbalier

Island and Wine Island collectively provide 259 acres of suitable habitat for piping

plover, although the islands have not been technically designated as critical habitat.

These three islands are located within the Isle Dernieres and Timbalier Island

Ranges, immediately adjacent to the islands in the NER Plan. There is also a

considerable amount of critical habitat near the Study boundary. For example, West

Belle Pass, Elmers Island, and East Grand Terre are located approximately 15

miles, 25 miles, and 40 miles east of Timbalier Island, respectively. Locust Bayou

and the Atchafalaya Delta offer additional critical habitat west of Raccoon Island.

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Suitable habitat can also be found at Point au Fer Island and at the numerous

pockets and sand and mudflats along coastal Louisiana.

During the Preliminary Engineering and Design (PED) phase, the USACE will

assess the feasibility of staggering the construction of the islands such that only one

island is disturbed at any point in time. Furthermore, the USACE will attempt to

adopt an every other island approach to construction. For example, Timbalier

Island would be constructed after Whiskey, followed by Trinity and then Raccoon.

This will minimize disturbance to the piping plover during construction and

maintain an abundance of critical habitat within the immediate vicinity of the

disturbed island. By staggering the initial construction of the islands in the NER

Plan, the renourishment events would also be staggered. However, constructing the

islands in series could significantly delay the completion of the project and inflate

project costs.

West Indian Manatee

Manatee occurrences have been regularly reported in the canals and coastline of

Louisiana. Collision with boats and barges is one of the primary anthropogenic

causes of manateemortalities. To avoid any impacts to the West Indian Manatee, all

contract personnel associatedwith the Study will be informed of the potential

presence of manatees and the need to avoid collisions with manatees, which are

protected under the Marine Mammal Protection Act of 1972and the Endangered

Species Act of 1973. All construction personnel will be required to monitor all waterrelated activities for the presence of manatee(s). Temporary signs will be posted

prior to and during all construction/dredging activities to remind personnel to be

observant for manatees during active construction/dredging operations or within

vessel movement zones (i.e., work area), and at least one sign will be placed where

it is visible to the vessel operator. Siltation barriers, if used by the contractor, will

be made of material in which manatees could not become entangled, and will be

properly secured per technical specifications provided by the manufacture. If a

manatee is sighted within 100 yards of the active work zone, special operating

conditions will be implemented, including:

 No operation of moving equipment within 50 ft of a manatee

 All vessels will operate at no wake/idle speeds within 100 yards of the work

area

 Siltation barriers, if used, will be monitored and re-secured as necessary

Once the manatee has left the 100-yard buffer zone around the work area on its own

accord, special operating conditions are no longer necessary, but careful

observations will resume. Care will also be taken to avoid entrapment of individuals

if any structure is to be installed that could be a barrier or impediment to manatee

movement.

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By implementing the above-mentioned manatee monitoring and avoidance program,

it is the USACE determination that the proposed NER Plan may affect, but will

not likely adversely affect the endangered West Indian Manatee.

Sea Turtles

Based on professional experience and related CWPPRA project construction

methods, it is anticipated that the contractor will use a hydraulic cutterhead dredge

and booster pump(s) to excavate sediment from the available offshore borrow

area(s) and directly transport it via a submerged sediment pipeline to the islands.

Environmental laws protecting sea turtles could possibly require the cessation of

work for a limited time if the allowable number of sea turtles mortalities is

exceeded during dredging. However, turtles are typically able to avoid cutterhead

dredge intakes because the dredges move along the seabed at such a slow speed.

Sediment used to construct the containment dikes will be dredged from existing

material inside the marsh creation area rather than from offshore borrow areas.

Therefore, dredging operations associated with the containment dikes are not

expected to adversely impact sea turtles.

In summary, it is the USACE determination that the borrow area dredging

operations may affect, but will not likely adversely affect populations of sea turtles

in the Study Area. Impacts associated with the actual placement of fill on the

islands are discussed below for each species of threatened/endangered sea turtles

identified by USFWS.

Green Sea Turtle

Due to the lack of extensive seagrass beds throughout much of coastal Louisiana,

and the low incidence of sightings and strandings, it is the Corps determination

that placement of fill on four islands in the NER Plan is expected to have no effect

on the green sea turtle population.

Hawksbill Sea Turtle

It is the Corps determination that placement of fill on the four islands in the NER

Plan will have no effect on hawksbill populations due to its rarity along the

Louisiana coast.

Kemps Ridley Sea Turtle

The proposed NER Plan would provide more suitable inshore habitat for foraging.

This habitat type is characterized by lower salinity and high turbidity and organic

content, where shrimp and blue crabs are abundant Therefore, it is the Corps

determination that placement of fill on the four islands in the NER Plan may

affect, but will not likely adversely affect populations of Kemps ridley sea turtles.

Leatherback Sea Turtle

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This pelagic species typically occupies oceanic waters of more than 160 ft (50 m) in

depth. Therefore, it is the Corps determination that placement of fill on the four

islands in the NER Plan is expected to have no effect on Leatherback sea turtle

populations.

Loggerhead Sea Turtle

Nesting loggerhead sea turtles have historically used barrier islands; however, it is

doubtful that loggerhead sea turtles nest anywhere on the Louisiana coast. The

restoration of Raccoon, Whiskey, Trinity, and Timbalier Island may or may not

provide suitable nesting habitat, but suitable nesting habitat is nearly nonexistent

due to the current degraded State of these islands. The NER Plan would not

negatively affect loggerheads and could potentially provide some benefit to the

species by restoring nesting habitat. Therefore, it is the USACE determination that

implementation of Alternative 5 (NER Plan) with placement of fill on Raccoon,

Whiskey, Trinity, and Timbalier Islands may affect, but will not likely adversely

affect populations of Loggerhead sea turtles.

Formal Consultation

Compliance with the ESA (7 U.S.C. 136; 16 U.S.C. 460 et seq.) has been coordinated

with the USFWS and the NMFS for those species under their respective

jurisdictions. The use of recommended primary activity exclusion zones and timing

restrictions would be utilized, to the maximum extent practicable, to avoid project

construction impacts to any threatened or endangered species or their critical

habitat within the Study Area. The USACE will continue to closely coordinate and

consult with the USFWS and the NMFS regarding threatened and endangered

species under their jurisdiction that may be potentially impacted by the proposed

action. Although the West Indian manatee and the Hawksbill, Kemps ridley,

Leatherback, Loggerhead, and Green sea turtles may be found in the Study Area,

the only endangered species with a high potential for adverse impacts from the

NER Plan is the piping plover. Multi-project research is currently underway to

determine the potential for diversion impacts to this species. Formal consultation

on the piping plover has been conducted and the USFWS has issued a Biological

Opinion (Annex A2). The USACE has agreed to comply with the RPM and the terms

and conditions outlined in the Biological Opinion and summarized in Sections

3.6.7.1 and 3.7.7.1.

5.11.1.2.2 Indirect

Compared to the No Action Alternative, implementing Alternative 5 (NER Plan)

would restore a net total of 565 acres of critical piping plover wintering habitat over

the four barrier islands including: 133 net acres on Raccoon, 118 net acres on

Whiskey, 87 net acres on Trinity, and 227 net acres on Timbalier Island.

Alternative 5 (NER Plan) would restore a net total of 2,781 acres with 2,883 AAHUs

of dune, supratidal and intertidal (gulfside and bayside) and shallow open water

habitats for use by not only the above described listed species, but also other fish

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and wildlife species. Alternative 5 (NER Plan) would restore the four barrier

islands to their minimal geormorphological form resulting, consistent with Stone

and McBride (1998), Stone et al. (2003) and Stone et al. (2005), in the restored

barrier islands absorbing wave energy during storms and fair-weather conditions

and providing some storm surge protection to adjacent estuarine system thereby

preventing the conversion of some unknown quantity of this transitional estuarine

habitat to shallow open water habitat. Restoring these four barrier islands to their

geomorphologic form would also contribute to their ecological function of providing

important and critical habitat for some listed species.

Alternative 5 (NER Plan) would reduce conversion of these transitional barrier

habitats to marine-dominated open water habitat thereby providing higher quality

EFH, especially nursery habitat, for several fishery species, including brown and

white shrimp, and blue crab as well as various benthic organisms. Vegetative

plantings would contribute to re-establishing a variety of wetland species that

would further aid in sediment trapping and barrier island stabilization. Vegetative

productivity would likely increase due to increased in vegetated acres on the barrier

islands. Important stopover habitats used by migrating neotropical birds would be

restored and sustained for future use over the 50-year period of analysis.

Alternative 5 (NER Plan) would also restore vegetation resources would, in turn,

provide important transitional habitat between estuarine and terrestrial

environments as well as unique habitats (e.g., nursery, nesting, feeding, and

roosting habitats). In addition, preventing/reducing the loss of estuarine wildlife

habitat resources would provide important fish and wildlife habitat which would

likely decrease competition between and within various fish and wildlife species for

diminishing habitat resources. The prevention/reduction of loss of barrier habitats

would also result in an undetermined increase in primary productivity compared to

the No Action Alternative.

Implementing Alternative 5 (NER Plan) would also restore a portion of the natural

services (recreation, aesthetics and water purification) and productivity (fish,

shellfish and fur) thereby reducing, to some unknown extent, the annual economic

loss to Louisiana and the nation (after Van Heerden and DeRouen 1997).

Furthermore, the proposed barrier shoreline restoration would contribute to the

Cajun culture and its people thereby indirectly impacting the States economy and

advancing by some unknown extent, the economic development of the State of

Louisiana.

5.11.1.2.3 Cumulative

Cumulative impacts would be the incremental impact from implementing

Alternative 5 (NER Plan) when added to all past, present and reasonably

foreseeable similar barrier island restoration efforts. Alternative 5 (NER Plan)

would restore a net total of 2,781 acres with 2,883 AAHUs of dune, supratidal,

intertidal (gulfside and bayside) and shallow open water wildlife habitats which

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include critical habitat for the piping plover. These impacts would be in addition to

impacts and benefits for overall net acres of barrier wildlife habitat resources

created, nourished, restored, and/or protected by other Federal, State, local, and

private restoration efforts. Cumulative impacts would be similar to Alternative 11,

but to lesser extent.

In addition, Alternative 5 (NER Plan) would restore the geomorphologic form to

Raccoon, Whiskey, Trinity and Timbalier Islands that would, consistent with Stone

(2005), enable these barrier islands to maintain their ecological function of

absorbing wave energy during storms and fair-weather conditions and provide some

undetermined level of storm surge protection and reduction of wave potential for

the Terrebonne interior estuarine wildlife habitat resources. These restoration

efforts would be in addition to other ongoing Federal, State and local restoration

efforts. Coastal barrier land loss in Louisiana has been addressed, to some degree,

by efforts under the Coastal Wetlands Planning, Protection and Restoration Act

(CWPPRA) program, and the beneficial use of dredged material requirements under

Section 307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq.

TY50.

5.11.1.3 Alternative 11: Whiskey (Plan C)

5.11.1.3.1 Direct

Compared to the No Action Alternative, direct impacts to listed species or their

designate critical habitat would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan), including initial restoration of a total 1,272

acres with 678 AAHUs with 65 acres of dune, 830 acres of supratidal, 377 acres of

intertidal resources on Whiskey Island. Alternative 11 would initially restore a total

of 624 acres of piping plover critical wintering habitat on Whiskey Island.

5.11.1.3.2 Indirect

Compared to the No-Action Alternative, indirect impacts to listed species or their

critical habitat of implementing Alternative 11 would be similar to those described

for the Whiskey Island component of Alternative 5 (NER). Alternative 11 would

restore a net total of 527 acres with 678 AAHUs of transitional barrier habitat

resources with 0 net acres dune, 164 net acres supratidal, and 363 net acres of

intertidal resources over the 50-year period of analysis. In addition, Alternative 11

would restore Whiskey Island to its minimal geomorphologic form which would

contribute to its ecological function of preventing conversion of the adjacent

Terrebonne Basin estuarine system, especially transitional wetland resources, to

open water habitat. Compared to the No Action Alternative, implementing

Alternative 11 would restore a net total of 118 acres of piping plover critical

wintering habitat on Whiskey Island.

5.11.1.3.3 Cumulative

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Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 11 restoring a net total of 527 acres with 678 AAHUs of

transitional barrier habitat resources on Whiskey Island, including a net total of

118 acres of piping plover critical wintering habitat.

Alternative 11 would also restore the minimal geomorphologic form to Whiskey

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.11.1.4 Alternative 2: Timbalier (Plan E)

5.11.1.4.1 Direct

Compared to the No Action Alternative, direct impacts to listed species or their

designate critical habitat would be similar to those described for the Timbalier

Island component of Alternative 5 (NER Plan), including initial restoration of a

total 2,630 acres with 1,110 AAHUs with 215 acres of dune, 2,346 acres of

supratidal, 69 acres of intertidal resources on Timbalier Island. Alternative 2 would

initially restore a total of 2,053 acres of piping plover critical wintering habitat on

Timbalier Island.

5.11.1.4.2 Indirect

Compared to the No-Action Alternative, indirect impacts to listed species or their

critical habitat of implementing Alternative 2 would be similar to those described

for the Timbalier Island component of Alternative 5 (NER Plan). Alternative 2

would restore a net total of 1,324 acres with 1,110 AAHUs of transitional barrier

habitat resources with 0 net acres dune, 236 net acres supratidal, and 1,088 net

acres of intertidal resources over the 50-year period of analysis. In addition,

Alternative 2 would restore Timbalier Island to its minimal geomorphologic form

which would contribute to its ecological function of preventing conversion of the

adjacent Terrebonne Basin estuarine system, especially transitional wetland

resources, to open water habitat. Compared to the No Action Alternative,

implementing Alternative 2 would restore a net total of 227 acres of piping plover

critical wintering habitat on Timbalier Island.

5.11.1.4.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey Island

component of Alternative 5 (NER Plan) including the synergistic interaction of the

impacts of Alternative 2 restoring a net total of 1,324 acres with 1,110 AAHUs of

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transitional barrier habitat resources on Timbalier Island, including a net total of

227 acres of piping plover critical wintering habitat.

Alternative 2 would also restore the minimal geomorphologic form to Timbalier

Island that would, consistent with Stone (2005), enable this barrier island to

maintain its function of absorbing wave energy during storms and fair-weather

conditions and provide some undetermined level of storm surge protection and

reduction of wave potential for the Terrebonne Basin estuarine wetland vegetation

resources. These incremental impacts would be in addition to similar impacts for

other barrier island restoration efforts across the Louisiana coastal area by other

Federal, State, and local barrier island restoration efforts.

5.11.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.11.1.5.1 Direct

Compared to the No Action Alternative, direct impacts to listed species or their

designate critical habitat would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan), including initial

restoration of a total 3,902 acres with 1,778 AAHUs with 280 acres of dune, 3176

acres of supratidal, 446 acres of intertidal wildlife habitat resources on Whiskey

and Timbalier Islands. Alternative 3 would initially restore a total of 2,677 acres of

piping plover critical wintering habitat on Whiskey and Timbalier Islands.

5.11.1.5.2 Indirect

Compared to the No-Action Alternative, indirect impacts to listed species or their

critical habitat of implementing Alternative 3 would be similar to those described

for the Whiskey and Timbalier Islands components of Alternative 5 (NER Plan).

Alternative 3 would restore a net total of 1,851 acres of transitional barrier habitat

resources with 0 net acres dune, 400 net acres supratidal, and 1,451 net acres of

intertidal habitat resources over the 50-year period of analysis. In addition,

Alternative 3 would restore Whiskey and Timbalier Islands to their minimal

geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially transitional wetland resources, to open water habitat. Compared to the

No Action Alternative, implementing Alternative 3 would restore a net total of 345

acres of piping plover critical wintering habitat on Whiskey Island.

5.11.1.5.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey and

Timbalier Islands components of Alternative 5 (NER Plan) including the synergistic

interaction of the impacts of Alternative 3 restoring a net total of 1,851 acres with

1,778 AAHUs of transitional barrier habitat resources on Whiskey and Timbalier

Islands, including a net total of 345 acres of piping plover critical wintering habitat.

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Alternative 3 would also restore the minimal geomorphologic form to Whiskey and

Timbalier Islands that would, consistent with Stone (2005), enable these barrier

islands to maintain their function of absorbing wave energy during storms and fairweather conditions and provide some undetermined level of storm surge protection

and reduction of wave potential for the Terrebonne Basin estuarine wetland

vegetation resources. These incremental impacts would be in addition to similar

impacts for other barrier island restoration efforts across the Louisiana coastal area

by other Federal, State, and local barrier island restoration efforts.

5.11.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.11.1.6.1 Direct

Compared to the No Action Alternative, direct impacts to listed species or their

designate critical habitat would be similar to those described for the Whiskey,

Trinity and Timbalier Islands components of Alternative 5 (NER Plan), including

initial restoration of a total 5,051 acres with 2,406 AAHUs with 409 acres of dune,

3,632 acres of supratidal, 1,010 acres of intertidal wildlife habitat resources on

Whiskey, Trinity and Timbalier Islands. Alternative 4 would initially restore a total

of 3,111 acres of piping plover critical wintering habitat on Whiskey and Timbalier

Islands.

5.11.1.6.2 Indirect

Compared to the No-Action Alternative, indirect impacts to listed species or their

critical habitat of implementing Alternative 4 would be similar to those described

for the Whiskey, Trinity and Timbalier Islands components of Alternative 5 (NER

Plan). Alternative 4 would restore a net total of 2,140 acres of transitional barrier

habitat resources with 0 net acres dune, 490 net acres supratidal, and 2,140 net

acres of intertidal habitat resources over the 50-year period of analysis. In addition,

Alternative 4 would restore Whiskey, Trinity and Timbalier Islands to their

minimal geomorphologic form which would contribute to their ecological function of

preventing conversion of the adjacent Terrebonne Basin estuarine system,

especially wildlife habitat resources, to open water habitat system, especially

transitional wetland resources, to open water habitat. Compared to the No Action

Alternative, implementing Alternative 3 would restore a net total of 432 acres of

piping plover critical wintering habitat on Whiskey, Trinity and Timbalier Islands.

5.11.1.6.3 Cumulative

Cumulative impacts would be similar to those described for the Whiskey, Trinity

and Timbalier Islands components of Alternative 5 (NER Plan) including the

synergistic interaction of the impacts of Alternative 4 restoring a net total of 2,140

acres with 2,406 AAHUs of transitional barrier habitat resources on Whiskey,

Trinity and Timbalier Islands, including a net total of 432 acres of piping plover

critical wintering habitat.

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Alternative 4 would also restore the minimal geomorphologic form to Whiskey,

Trinity and Timbalier Islands that would, consistent with Stone (2005), enable

these barrier islands to maintain their function of absorbing wave energy during

storms and fair-weather conditions and provide some undetermined level of storm

surge protection and reduction of wave potential for the Terrebonne Basin estuarine

wetland vegetation resources. These incremental impacts would be in addition to

similar impacts for other barrier island restoration efforts across the Louisiana

coastal area by other Federal, State, and local barrier island restoration efforts.

5.12 CULTURAL AND HISTORIC RESOURCES

Various prehistoric archaeological studies of the barrier island zones of the

Mississippi Deltas have been summarized by Nowak, et al. (2010) and Goodwin, et

al.(1991). They indicate that the primary settlement areas for prehistoric peoples

were natural levees and other elevated features associated with bayous,

particularly following delta or distributary abandonment. Some settlement has

been reported from the barrier islands, but it is postulated that the islands and

beaches were mainly exploited for their shellfish resources. Historically, permanent

settlement on the Terrebonne Basin Barrier Islands occurred in the nineteenth

century, but ceased mid-century, when the modest resort community on Isle

Dernieres was destroyed by a hurricane in 1856 (Sallenger, 2009). Subsequent

human habitation has been restricted to seasonal fishing camps and petroleum

processing and transmission facilities.

On July 29, 2010, the USACE executed a Programmatic Agreement among the

USACE, CPRA, SHPO, and ACHP, pursuant to 36 CFR § 800.14(b)(1). The

Programmatic Agreement establishes the procedures for consultation, identification

of historic properties, and assessment and resolution of adverse effects (Appendix

F). The execution and implementation of the Programmatic Agreement fulfills

USACE obligations under Section 106 of the National Historic Preservation Act of

1966, as amended. The Programmatic Agreement will be implemented during PED.

5.12.1.1 No Action Alternative (Future without Project Conditions)

5.12.1.1.1 Direct

The No Action Alternative, not implementing coastal barrier system restoration,

would present no immediate direct impacts to historic properties. Any undiscovered

or unreported cultural resources or traditional cultural properties would remain

intact and in their current State of preservation.

5.12.1.1.2 Indirect

As the barrier islands and interior marshes erode and/or subside, prehistoric

cultural resources could become exposed to elements or inundated, putting them at

a greater risk of damage or destruction. However, Nowak (ibid.) points out that no

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prehistoric archaeological sites have been recorded within the areas of potential

effect (APE) for the islands of the Study. The historic cultural resources,

particularly those associated with the petroleum industry, will become increasingly

vulnerable to adverse impacts over time from storm damage, as the barrier islands

and marshes continue to degrade.

5.12.1.1.3 Cumulative

As described in the preceding paragraph, both barrier island and inland cultural

resources, in the broadest sense, will continue to be adversely affected and become

increasingly vulnerable over time. This vulnerability extends to settled areas

located along the natural levees that extend into the basin, including established

communities such as Cocodrie. The latter is a center for recreational fishing and

the site of the Louisiana Universities Marine Consortium (LUMCON), a renowned

and significant educational and scientific research facility

5.12.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.12.1.2.1 Direct

Nowak (ibid.) indicates that there is a low probability for significant prehistoric

archaeological sites or prehistoric watercraft, historic archaeological sites or

standing structures within the Raccoon Island and Whiskey Island APEs. Within

the Raccoon Island APE, a high probability for historic shipwrecks is indicated near

Raccoon Point, while a moderate probability for such resources is present to the east

of this area. A low probability for historic shipwrecks is indicated along the entire

Gulf Coast of the island, since waters south of the shoreline within the APE were

subaerially exposed until the mid-twentieth century. The northwestern portion of

the Whiskey Island APE has a moderate probability for historic shipwrecks, but

areas within the APE south and west of this region were subaerially exposed until

the mid-twentieth century; thus, they should be considered to have low potential for

historic shipwrecks. A Phase I submerged cultural resources remote sensing

investigation was conducted by R. Christopher Goodwin and Associates, Inc. within

the vicinity of Whiskey Island (Nowak et al. 2010b). Thirteen (13) targets

potentially representing submerged cultural resources were identified. However,

none of the magnetic anomalies that compose those targets could be associated with

side scan sonar contacts, suggesting that all thirteen (13) targets are buried. There

will be no direct impacts to historic properties if the targets representing potential

historic properties are avoided. A Phase 1 remote sensing submerged cultural

resource investigation of the Raccoon and Timbalier Island areas having a high and

moderate potential for historic shipwrecks shall be completed prior to construction

activities, and any targets representing potential historic shipwrecks shall be

avoided. No historic properties have been identified in the Raccoon Island, Trinity

Island, and Timbalier Island APEs; therefore, no direct impacts to historic

properties are anticipated.

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5.12.1.2.2 Indirect

Shoreline stabilization and dune and marsh restoration on the four islands will

reduce ongoing land loss and erosion in the Study Area behind those the islands,

which will reduce impacts to cultural resources in the interior marshes and uplands

(Stone & McBride, 1998; Stone, et al., 2005).

5.12.1.2.3 Cumulative

The cumulative impacts of implementing Alternative 5 would be similar to the

previously-described indirect impacts. Over time, as the islands themselves are

eroded, their mitigative effects will diminish. The proposed periodic renourishment

will restore the protection they afford the interior marshes and uplands.

5.12.1.3 Alternative 11: Whiskey (Plan C)

5.12.1.3.1 Direct

There is a low probability for significant prehistoric archaeological sites or

prehistoric watercraft, historic archaeological sites or standing structures within

the Whiskey Island APE. The northwestern portion of the Whiskey Island APE has

a moderate probability for historic shipwrecks, but areas within the APE south and

west of this region were subaerially exposed until the mid-twentieth century; thus,

they should be considered to have low potential for historic shipwrecks. A Phase I

submerged cultural resources remote sensing investigation was conducted by R.

Christopher Goodwin and Associates, Inc. within the vicinity of Whiskey Island

(Nowak et al. 2010b). Thirteen (13) targets exhibiting the potential to represent

submerged cultural resources were identified, although none of the magnetic

anomalies that compose those targets could be associated with side scan sonar

contacts, suggesting that all thirteen (13) targets are buried. There will be no direct

impacts to historic properties if the targets representing potential historic

properties are avoided.

5.12.1.3.2 Indirect

Because Whiskey Island is so close to the interior marshes (approximately 1 mile to

the north) its shoreline stabilization and dune and marsh creation will provide

protection to the cultural resources associated with those wetlands. Such protection

will not benefit the interior marshes and uplands in the lee of the remaining

Terrebonne barrier islands.

5.12.1.3.3 Cumulative

The cumulative impact of Whiskey Island restoration will be the above-referenced

protection afforded the adjacent marsh and upland areas. With the anticipated

renourishment events at TY20 and TY40 such protection would last through the 50-

year period of analysis. Should there be other Federal, State, local, and private

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restoration efforts to provide complementary protection for the barrier islands, it

would extend to providing protection to inland cultural resources.

5.12.1.4 Alternative 2: Timbalier (Plan E)

5.12.1.4.1 Direct

There is a low probability for significant prehistoric archaeological sites or

prehistoric watercraft, historic archaeological sites or standing structures within

the Timbalier Island APE; however, there is a moderate probability for historic

shipwrecks. A portion of the Timbalier Island APE was investigated recently by

Coastal Environments, Inc. (Kelley et al. 2009). No significant cultural resources

were identified during that study. As a result, only the areas immediately adjacent

to but outside of the footprint of the aforementioned Coastal Environments, Inc.

investigation can be considered to have a moderate potential for historic

shipwrecks. A Phase 1 submerged cultural resource investigation of the area

having a moderate potential for historic shipwrecks shall be completed prior to

construction activities, and any targets representing potential historic shipwrecks

shall be avoided. No historic properties have been identified in the Timbalier Island

APE; therefore, no direct impacts to historic properties are anticipated.

Both the South Pelto Borrow Area 6 and the Whiskey Island Restoration Borrow Area 3 have

been investigated, and targets representing potentially significant cultural resources will be

avoided. The borrow area limits and avoidance areas are included in Appendix L. There will be

no direct impacts to historic properties if the targets representing potential historic properties are

avoided.

5.12.1.4.2 Indirect

Because Timbalier Island is well-removed from the marshes and uplands to its

north, indirect impacts of implementing Alternative 2 would be minimal, and would

be confined to protection of nearby petroleum industry infrastructure.

5.12.1.4.3 Cumulative

Cumulative impacts of implementing Alternative 2 would be the above-referenced

protection to nearby petroleum industry infrastructure. With the anticipated

renourishment at TY30 this protection should last through the 50-year period of

analysis for the Study. As with Alternative 11, should there be other Federal,

State, local, and private restoration efforts to provide complementary protection for

the barrier islands, it would extend to providing protection to inland cultural

resources.

5.12.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.12.1.5.1 Direct

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Direct impacts of implementing Alternative 3 would be a combination of those

described for Alternative 11 and Alternative 2, with the addition of use of the

Raccoon Island Restoration Borrow Area 5.

The Raccoon Island Restoration Borrow Area 5 has been investigated, and targets

representing potentially significant cultural resources will be avoided. The borrow

area limits and avoidance areas are included in Appendix L. There will be no direct

impacts to historic properties if the targets representing potential historic

properties are avoided

5.12.1.5.2 Indirect

Indirect impacts of implementing Alternative 3 would be a combination of those described for

Alternative 11 and Alternative 2.

5.12.1.5.3 Cumulative

Cumulative impacts of implementing Alternative 3 would be a combination of those described

for Alternative 11 and Alternative 2.

5.12.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.12.1.6.1 Direct

The direct impacts of implementing Alternative 4 would include those described for

Alternative 11, Alternative 2, and Alternative 3, with the addition of the Trinity

Island APE and the and New Cut Borrow Area 4.

There is a low probability for significant prehistoric archaeological sites or

prehistoric watercraft, historic archaeological sites or standing structures within

the Trinity Island APE. The Trinity Island APE was largely subaerially exposed

until the mid-twentieth century and is considered to have low probability for

historic shipwrecks. No historic properties have been identified in the Trinity

Island APE; therefore, no direct impacts to historic properties are anticipated.

The New Cut Borrow Area 4 has been investigated, and targets representing

potentially significant cultural resources will be avoided. The borrow area limits

and avoidance areas are included in Appendix L. There will be no direct impacts to

historic properties if the targets representing potential historic properties are

avoided.

5.12.1.6.2 Indirect

Indirect impacts of implementing Alternative 4 would be a combination of those

described for Alternative 3 and the above-referenced minimal impacts from the

Trinity Island APE and the New Cut Borrow Area 4.

5.12.1.6.3 Cumulative

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Cumulative impacts of implementing Alternative 4 would be a combination of those

described for Alternative 3, the above-referenced minimal impacts from the Trinity

Island APE, the New Cut Borrow Area 4, and the long-term protection for any

cultural resources afforded by the protection resulting from Trinity Island

renourishment at TY25. This protection should last through the 50-year period of

analysis for the Study. As with Alternative 11, should there be other Federal,

State, local, and private restoration efforts to provide complementary protection for

the barrier islands, it would extend to providing protection to inland cultural

resources.

5.13 AESTHETICS

5.13.1.1 No Action Alternative (Future without Project Conditions)

5.13.1.1.1 Direct

The visual complexity surrounding the Study Area is related to its geomorphic

structures including beach, dune, and marsh. All of these elements are critical

systems inclusive to the Terrebonne Basin Barrier Shoreline System. Together, all

of these elements provide a pleasing aesthetic view shed to the public.

5.13.1.1.2 Indirect

Without implementation of the barrier restoration features, existing conditions will

persist resulting in the continued loss and degradation of the barrier islands.

Degradation of the barrier islands would convert existing views of beach, dune, and

wetland to more open water views.

5.13.1.1.3 Cumulative

Cumulative impacts would be the synergistic effect of the No-Action Alternative on

aesthetic resources with the additive combination of similar impacts from wetland

loss and degradation throughout coastal Louisiana, as well as the benefits and

impacts of other State and Federal projects in the vicinity.

5.13.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.13.1.2.1 Direct

Viewscapes would be disturbed by construction activities and the use of rock as a

shoreline protection structure. There may be some perceived visual disturbance as

an unnatural terminal groin structure is placed at the end of Raccoon Island. Even

though the shoreline protection features would remain visually disruptive, the

visual benefits surrounding the protection of visually complex wetlands viewscapes

would outweigh the slight negative impact on aesthetics.

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With the implementation of any shoreline protection feature, the viewscapes around

the Study Area would experience limited short-term disruption imposed by the

working activities of the floating dredge plant. These minor impacts would be

localized and temporary. The Study Area should quickly stabilize, and the newly

created, nourished and protected emergent wetlands would provide new high

quality viewscapes as well as protect existing ones.

5.13.1.2.2 Indirect

Indirect impacts to visual resources would primarily result from newly created high

quality emergent wetland viewscapes that would provide a long-term visual

enhancement of an area that is presently experiencing a decline in visual

complexity.

5.13.1.2.3 Cumulative

Cumulative impacts would be the synergistic effect with the additive combination of

impacts and benefits for overall net acres created, nourished, and protected by other

Federal, State, local, and private restoration efforts. Alternative 11 would work

synergistically with those projects to provide more complete protection for the

barrier islands, which would increase the quality of the visually complex viewscapes

throughout the Study Area. Cumulative impacts of maintaining appealing

viewscapes would also support eco-tourism as one travels Louisianas Scenic

Byways and remote areas of visual interest.

5.13.1.3 Alternative 11: Whiskey (Plan C)

5.13.1.3.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.13.1.3.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.13.1.3.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

Alternative 2: Timbalier (Plan E)

5.13.1.3.4 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.13.1.3.5 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.13.1.3.6 Cumulative

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Cumulative impacts would be similar to Alternative 5 (NER Plan)

5.13.1.4 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.13.1.4.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.13.1.4.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.13.1.4.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.13.1.5 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.13.1.5.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.13.1.5.2 Indirect

Indirect impacts are similar to Alternative 5 (NER Plan).

5.13.1.5.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.14 RECREATION

As described in Section 4.2.14, above, the primary recreational activities on the

Terrebonne Basin Barrier Islands and their adjacent marshes and surface waters

are hunting and fishing. With the exception of mainland shoreline-based waterfowl

hunting and wading-depth fishing, watercraft are necessary to undertake

recreational activities on the marshes, islands, and in open water of the Terrebonne

Basin. All of these recreational activities provide business for charter fishermen,

private marinas and boat launching facilities, and local supply and service

companies (USFWS, 2003).

The Terrebonne Basin is a hot spot for fishing and boating activities in coastal

Louisiana, primarily because the uninhabited barrier islands (including their

associated marshes) still provide protective and productive habitats for a range of

fisheries resources. While many anglers visit the Terrebonne Basin with their own

boats, and utilize boat launching sites, there is a large population who own, co-own,

or rent houses and fishing camps located on the bayou and canal shorelines. The

concentrations of these are centered along the Houma Navigation Canal, in the

vicinity of Dulac, along Bayou Petite Caillou, approaching Cocodrie, and along

Bayou Lafouche, approaching Port Fourchon. Cocodrie itself has more fishing

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camps and marinas than any other urban area in coastal Louisiana. Table 5-9

presents data for facilities in the vicinity of Cocodrie and Holly Beach, on the Gulf

in Cameron Parish. Both communities are centers of recreational activity.

Table 5-9: Facilities in the Vicinity of Cocodrie

Location Marinas/Charter

Docks

Houses/Camps Nearest City

Cocodrie, LA 7 >400 Houma  31 miles N

Holly Beach, LA 2 >150 Cameron  10 miles E

5.14.1.1 No Action Alternative (Future without Project Conditions)

5.14.1.1.1 Direct

The No Action Alternative, not implementing barrier island restoration features,

would have no direct impacts on oyster leases recreation resources. Existing

conditions would persist. Much of the recreational activity occurring in Louisiana

consists of hunting, fishing, and wildlife viewing and photography. Recreational

resources in the Louisiana coastal zone that would be most affected in the Future

Without-Project conditions are those related to loss of wetlands/marshes and

habitat diversity. The general trend in wildlife abundance has been a decrease in

wildlife numbers in areas experiencing high land loss and an increase in areas of

freshwater input or land building due to restoration projects. Populations of

migratory birds and other animals directly dependent on the marsh and swamp

would decrease dramatically, an impact which would be felt in much of North

America, where many of these migratory species spend parts of their life cycles.

With the continued conversion of marsh to open water, much of the fishery

productivity would be expected to peak followed by a sharp decline.

5.14.1.1.2 Indirect

The coastal zones changing environment would affect the recreational resources

within that area. As existing barrier islands are lost and freshwater wetland/marsh

areas transition to saltwater marsh, and subsequently to open water, the

recreational opportunities would change accordingly: in part from actual habitat

shift and in part from loss of the nursery functions provided by that habitat. As

populations of freshwater and/or saltwater species decline, so would fishing

opportunities (including crawfishing, crabbing, oyster harvesting, and recreational

shrimping). In transitional and upland areas where populations of game species

exist, hunting opportunities would be reduced as the landscape became less

supportive of those species. The same holds true for the populations of migratory

waterfowl and other bird species, which will affect opportunities for viewing.

Another major impact of barrier island land loss, and land loss in general, is the

possible loss of facilities and infrastructure that support or are supported by

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recreational activities. Land loss can literally result in the loss of boat launches,

parking areas, access roads, marinas, and supply shops. The loss of access features,

such as roads and boat launches, directly impacts an individuals ability to recreate

in particular areas. The economic loss felt by marinas and other recreational service

and supply providers may be two-fold. One is potential loss of the actual facility or

access to the facility; the other is change in opportunities. Habitat change and

resulting changing recreation opportunities (i.e., fresh water to marine) may for

example severely impact a marina specializing in services for particular types of

recreation (i.e., a shift from freshwater to estuarine and offshore fishing might

necessitate changes in boat slip dimensions, deepening of basins, and access

channels to accommodate a different mix of recreational vessels).

5.14.1.1.3 Cumulative

Without action, the recreation needs identified by the SCORP for the Terrebonne

Basin in general, and the Study Area in particular, will increase. Land loss in

general, particularly the gradual loss of the barrier islands, coupled with conversion

of marsh to open water, will undoubtedly be the largest impact to recreation

resources. Over time, conversion of marsh to open water will result in a decline of

estuary-dependent recreation. Access to marsh-based recreation opportunities,

another identified need, will also be impacted by predicted land loss.

5.14.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.14.1.2.1 Direct

The immediate direct recreational resources impact from implementation of the

NER Plan would be temporary closure of each islands Study Area during

construction. In addition, there will be a temporary decrease in the quality of

recreational opportunities as the wetland restoration sites are allowed to settle,

vegetation is restored, and tidal circulation is reestablished naturally. The

recreational benefits and opportunities will rebound as the restored marshes take

root. It is important to understand that both Raccoon and Whiskey Islands are part

of the Terrebonne Barrier Islands Refuge, managed by the Louisiana Department of

Wildlife and Fisheries, which is closed to the public. The surrounding waters are

available for recreation, but trespass on the islands themselves is prohibited. As

formulated, the plan involves filling several canals on both Trinity and Timbalier

Islands. These canals were excavated and have been maintained to provide access

to oil or gas wells, and continued service/maintenance access will have to be

accommodated in cooperation with the well owners. The canals are periodically used

as mooring areas for houseboats and their elimination will have a negative impact

on that form of recreation.

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5.14.1.2.2 Indirect

Alternative 5 (NER Plan) will protect, create and nourish transitional estuarine

wetlands. Following construction, these transitional estuarine wetlands will provide

important and essential fish and wildlife habitats that will contribute to restoring

and nurturing the food chain for the organisms that provide the base for

recreational activities such as fishing, wildlife viewing, and camping. Increased

opportunity for recreational activities will come from expansion of new vegetative

habitat on newly created areas and the protection from storm-related stressors that

the restored beach, dune, and marsh areas will afford adjacent existing habitats.

5.14.1.2.3 Cumulative

The cumulative impacts from implementing the NER Plan would be provision of the

above-referenced recreational benefits into the future, assuming that the proposed

renourishment events are undertaken. Should other Federal, State, local, and

private restoration efforts be forthcoming, they will provide an additive combination

of impacts and benefits for overall net acres created, nourished, and protected.

Alternative 5 (NER Plan) will work synergistically with those projects to provide

more complete protection for barrier islands, which will continue to provide

wetland-dependent recreational opportunities in the Study Area.

5.14.1.3 Alternative 11: Whiskey (Plan C)

5.14.1.3.1 Direct

The primary direct impact on recreational resources will result from the Study Area

being temporarily unavailable during construction. In addition, there will be a

temporary decrease in the quality of recreational opportunities as the wetland

restoration sites are allowed to settle, vegetation is restored, and tidal circulation is

reestablished naturally. The recreational benefits and opportunities will rebound

as the restored marshes take root.

5.14.1.3.2 Indirect

Alternative 11 will protect, create and nourish a transitional estuarine wetland on a

single island. Following construction, this transitional estuarine wetland will

provide important and essential fish and wildlife habitat that will contribute to

restoring and nurturing the food chain for the organisms that provide the base for

recreational activities such as fishing and wildlife viewing. Increased recreation

activity will come from expansion of new vegetative habitat on newly created areas

and the protection from storm-related stressors that the restored beach, dune, and

marsh areas will afford adjacent existing habitats.

5.14.1.3.3 Cumulative

The cumulative impacts from implementing the recommended component of

construction plan would be provision of the above-referenced recreational benefits

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into the future, assuming that the proposed renourishment events are undertaken.

Should other Federal, State, local, and private restoration efforts be forthcoming,

they will provide an additive combination of impacts and benefits for overall net

acres created, nourished, and protected. Alternative 11 will work synergistically

with those projects to provide more complete protection for barrier islands, which

will continue to provide wetland-dependent recreational opportunities in the Study

Area.

5.14.1.4 Alternative 2: Timbalier (Plan E)

5.14.1.4.1 Direct

Direct impacts would be similar to Alternative 11, with recreational activity

curtailed during construction, and rebounding of both benefits and opportunities

following restoration and vegetation reestablishment.

5.14.1.4.2 Indirect

Indirect impacts would be similar to Alternative 11 because this too is a single

island effort. However, because Timbalier Island is not part of the Terrebonne

Barrier Island Reserve, camping and land-based recreation are not prohibited, and

would benefit from the habitat improvement.

5.14.1.4.3 Cumulative

Cumulative impacts would be similar to Alternative 11, assuming that the proposed

renourishment event occurs at TY30.

5.14.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.14.1.5.1 Direct

Direct impacts would be less than those for Alternative 5 (NER Plan), because this

alternative only involves two of the four islands.

5.14.1.5.2 Indirect

As with the direct impacts, the indirect impacts would be the same as for

Alternative 5 (NER Plan), but of a reduced magnitude and scope because they only

involve two islands.

5.14.1.5.3 Cumulative

The cumulative impacts would be the same as for Alternative 5 (NER Plan), but of a

reduced magnitude and scope because they are only derived from two islands.

5.14.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.14.1.6.1 Direct

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Direct impacts would be a reduction of those for Alternative 5 (NER Plan) because

the alternative only derives benefits from restoration of three of the four islands.

However, because neither Trinity nor Timbalier Islands are included in the

Reserve, both camping and land-based recreation will be available after completion

of construction.

5.14.1.6.2 Indirect

As with the direct impacts the indirect impacts would be similar to Alternative 5

(NER Plan), but reduced because they are derived from three islands, while the

NER Plan is for four islands.

5.14.1.6.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan) but somewhat

reduced because the benefits derived from restoration of Raccoon Island will be

missing. Because Whiskey Island will be renourished in TY20 and TY40, and the

others in TY25 and TY30, there will be localized disruption due to construction

throughout the 50-year planning period. The overall benefits from restoring the

barrier island habitats obviously outweigh the limited disturbance.

5.15 SOCIOECONOMICS AND HUMAN RESOURCES

5.15.1 Population and Housing

5.15.1.1 No Action Alternative (Future without Project Conditions)

The Study area is uninhabited and inaccessible, except by boat or aircraft. Five of

the islands (Raccoon, Whiskey, Trinity/East and Wine) make up the Isles Dernieres

Barrier Islands Refuge (IDBIR) which is managed by the LDWF. Access to the

IDBIR is regulated by the LDWF. As referenced in the previous section, there are

transient campers, often based from houseboats, and a few camp type structures

on Timbalier and East Timbalier Islands. In addition, there are several petroleum

transmission and processing facilities on or north of the latter two islands that

appear to have crew accommodations

5.15.1.1.1 Direct

The No Action Alternative for population and housing would have no direct impacts

on human populations. Not implementing wetland creation/ nourishment and

shoreline protection features would result in the persistence of existing conditions.

The Study Area is a remote and uninhabited marsh and there are no human

populations and/or housing are within the Study Area.

5.15.1.1.2 Indirect

There is no population residing within the Study Area, and the proposed action

would have no indirect impacts outside the Study Area.

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5.15.1.1.3 Cumulative

The cumulative impact of no further action would lead to continuing erosion of the

barrier islands and their associated wetland and marsh habitats. Left unchecked,

the loss of wetland and marsh would continue progressing north in the Terrebonne

Basin to the point where it could diminish protection for inhabited areas, such as

Cocodrie and Port Fourchon, as well as for the numerous petroleum transmission

and processing facilities scattered across Terrebonne and Timbalier Bays and their

marshes.

5.15.1.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.1.2.1 Direct

The direct impacts would be the same as the No Action Alternative

5.15.1.2.2 Indirect

The indirect impacts would be the same as the No Action Alternative

5.15.1.2.3 Cumulative

The cumulative impact of implementing the NER Plan would be to retard the

erosion of the islands and their associated wetlands and marshes, thus reducing the

potential for land loss to the north. Should other Federal, State, local, and private

restoration efforts be forthcoming, they will provide an additive combination of

impacts and benefits for overall net acres created, nourished, and protected.

Alternative 5 (NER Plan) will work synergistically with those projects to provide

more complete protection for the barrier islands and the inhabited areas to the

north in the Terrebonne Basin.

5.15.1.3 Alternative 11: Whiskey (Plan C)

5.15.1.3.1 Direct

There is no population residing within the Study Area, and the proposed action

would have no direct impacts outside the Study Area.

5.15.1.3.2 Indirect

There is no population residing within the Study Area, and the proposed action

would have no indirect impacts outside the Study Area.

5.15.1.3.3 Cumulative

The cumulative effect of restoration of a single barrier island will be minimal. The

protection a restored Whiskey Island affords the immediately adjacent wetlands,

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which are also uninhabited, will have no impact on population or housing. Should

other Federal, State, local, and private restoration efforts be forthcoming in the

Terrebonne Basin, they will provide an additive combination of impacts and

benefits for overall net acres created, nourished, and protected. Alternative 11 will

work synergistically with those projects to provide more complete protection for the

barrier islands and the inhabited areas to the north in the Terrebonne Basin.

5.15.1.4 Alternative 2: Timbalier (Plan E)

5.15.1.4.1 Direct

Direct impacts would be similar to the Timbalier component of Alternative 5 (NER

Plan).

5.15.1.4.2 Indirect

Indirect impacts would be similar to the Timbalier component Alternative 5 (NER

Plan).

5.15.1.4.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan), but to a lesser

extent.

5.15.1.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.1.5.1 Direct

Direct impacts would be similar to the Whiskey/Timbalier Island components of

Alternative 5 (NER Plan).

5.15.1.5.2 Indirect

Indirect impacts would be similar to the Whiskey/Timbalier Island components of

Alternative 5 (NER Plan).

5.15.1.5.3 Cumulative

Cumulative impacts would be similar to the Whiskey/Timbalier Islands component

of Alternative 5 (NER Plan), but of a reduced magnitude and scope because they are

only derived from two islands.

5.15.1.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.1.6.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan) without Raccoon

Island.

5.15.1.6.2 Indirect

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Indirect impacts would be similar to Alternative 5 (NER Plan) without Raccoon

Island.

5.15.1.6.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan) without Raccoon

Island.

5.15.2 Employment and Income

5.15.2.1 No Action Alternative (Future without Project Conditions)

The Study area is uninhabited and inaccessible, except by boat or aircraft. Five of

the islands (Raccoon, Whiskey, Trinity/East and Wine) make up the Isles Dernieres

Barrier Islands Refuge (IDBIR) which is managed by the LDWF. Access to the

IDBIR is regulated by the LDWF. Regarding employment and income, there are no

businesses or other employment opportunities on the barrier islands. As referenced

in the previous section, there are several petroleum transmission and processing

facilities on or north of Timbalier and East Timbalier Islands that appear to have

crew accommodations and there are other, less elaborate facilities scattered behind

and between the islands that obviously require routine servicing/maintenance, but

those activities appear to be based from mainland communities, such as Cocodrie

and Port Fourchon. Extensive commercial fishing, guided recreational fishing, and

ecotourism are undertaken in the Terrebonne Basin and around the barrier islands.

Like the aforementioned service/maintenance activities, these, too, are based from

mainland communities, notably Cocodrie and Dulac.

5.15.2.1.1 Direct

The No Action Alternative, not implementing the barrier restoration features,

would have no direct impacts on employment or income.

5.15.2.1.2 Indirect

Indirect impacts would result in the persistence of existing conditions including

continued wetland loss and degradation of the barrier islands and coastal wetlands

north of the Study Area. This continued wetland loss would have some localized

impacts on employment and income if it resulted in abandonment or relocation of oil

and gas distribution/processing facilities.

5.15.2.1.3 Cumulative

The impacts of wetland loss and degradation of the barrier islands will lead to a

decline in transitional wetland habitats, an important EFH which, in turn, could

lead to some undetermined level of economic decline in local fishery-related

employment and income. The aforementioned impact on oil and gas distribution/

processing facilities could extend north into the Terrebonne Basin, as the remaining

Basin wetlands deteriorate.

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5.15.2.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.2.2.1 Direct

Direct impacts would be similar to the No Action Alternative, as there are no

businesses or employment opportunities on the four islands.

5.15.2.2.2 Indirect

Alternative 5 (NER Plan) will protect, create and nourish transitional estuarine

wetlands. Following construction, these transitional estuarine wetlands will provide

important and essential fish and wildlife habitats that will contribute to restoring

and nurturing the food chain for the organisms that provide the base for commercial

and recreational activities such as fishing and ecotourism. Restored and protected

wetlands could obviate the need for abandonment or relocation of otherwise

vulnerable oil and gas facilities, and the employment opportunities that accompany

them.

5.15.2.2.3 Cumulative

The cumulative impacts from implementing the NER Plan would be provision of the

above-referenced employment and income benefits into the future, assuming that

the proposed renourishment events are undertaken. Should other Federal, State,

local, and private restoration efforts be forthcoming, they will provide an additive

combination of impacts and benefits for overall net acres created, nourished, and

protected. Alternative 5 (NER Plan) will work synergistically with those projects to

provide more complete protection for barrier islands, which will continue to provide

wetland-dependent employment opportunities in the Study Area.

5.15.2.3 Alternative 11: Whiskey (Plan C)

5.15.2.3.1 Direct

As part of the aforementioned wildlife refuge, trespass on Whiskey Island is

prohibited. Restoration of this single island will have no direct impact on

employment and income, as there are no businesses or employment opportunities

on the island. Commercial and recreational fishing will be temporarily curtailed

during construction in the Study Area These activities can resume after

construction is completed. The creation of a transitional estuarine wetland on the

island will provide important and essential fish and wildlife habitat that will

contribute to restoring and nurturing the food chain for the organisms that provide

the base for commercial and recreational activities, such as fishing and ecotourism

(wildlife viewing, etc.), thus facilitating income generation. Implementing this

alternative could result in turbidity or fill impacts on several oyster leases near the

Study Area

5.15.2.3.2 Indirect

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Implementing this single island alternative would provide limited benefits to

commercial and recreational fisheries by increasing the quantity and quality of

essential fish habitat available for nursery and other aquatic life functions. In

addition this alternative provides some protection of adjacent oyster leases from

being directly exposed to the higher saline waters of the Gulf.

5.15.2.3.3 Cumulative

The cumulative impact of Whiskey Island restoration will be protection afforded the

adjacent marsh and upland areas, thus facilitating productivity of fisheries

resource, including oysters. With the anticipated renourishment events at TY20

and TY40 such protection would last through the 50-year period of analysis. Should

there be other Federal, State, local, and private restoration efforts to provide

complementary protection for the barrier islands and the fishery resources they

nurture.

5.15.2.4 Alternative 2: Timbalier (Plan E)

5.15.2.4.1 Direct

Even though Timbalier Island is not within the Terrebonne Barrier Islands Refuge,

the direct impacts would be similar to Alternative 11. The restoration and

subsequent renourishment in TY30 would protect the oil and gas transmission and

processing infrastructure located behind the island, which continues to provide

employment opportunities. Should those facilities be abandoned or relocated, those

opportunities would be eliminated.

5.15.2.4.2 Indirect

As above, the indirect impacts of restoration of a single island would be similar to

Alternative 11 and to the aforementioned directs impacts.

5.15.2.4.3 Cumulative

The cumulative impacts would be similar to those from Alternative 11), however

there is only one renourishment event, planned for TY30. In addition, the

aforementioned petroleum infrastructure protection would persist through the 50-

year planning period for the project.

5.15.2.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.2.5.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan), but reduced in scale

because this alternative only involves restoration of two islands.

5.15.2.5.2 Indirect

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Indirect impacts would be similar to Alternative 5 (NER Plan), but reduced in scale

because this alternative only involves restoration of two islands.

5.15.2.5.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan), but reduced in

scale because this alternative only involves restoration of two islands.

5.15.2.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.2.6.1 Direct

The direct impacts would be similar to Alternative 5 (NER Plan), but reduced in scale

because this alternative only involves restoration of three islands. As with Alternatives 2 and

3, the petroleum infrastructure located at Timbalier Islands would be afforded

protection, which translates into continued employment for service technicians and

other workers.

5.15.2.6.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan), but reduced in scale

because this alternative only involves restoration of three islands.

5.15.2.6.3 Cumulative

C Cumulative impacts would be similar to Alternative 5 (NER Plan), but reduced in

scale because this alternative only involves restoration of three islands.

5.15.3 Community Cohesion

5.15.3.1 No Action Alternative (Future without Project Conditions)

The No Action Alternative would have no direct impacts on community cohesion.

Not implementing wetland creation/nourishment and shoreline protection features

would result in the persistence of existing conditions. The Study Area is remote and

uninhabited barrier islands, with no communities or permanent population.

5.15.3.1.1 Indirect

The No Action Alternative would have no indirect impact on community cohesion

because the Study Area is uninhabited.

5.15.3.1.2 Cumulative

The No Action Alternative may have cumulative impacts on community cohesion if

the islands continue to erode to the point where the interior wetlands cease to

protect the upland communities. If the communities are jeopardized by increasingly

frequent tidal inundation and storm surge impacts abandoning them may be more

cost-effective than constructing and maintaining levees or other barriers. In

addition, conversion of Terrebonne Bay to an open water habitat, with loss of the

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marshes and estuarine environment, will have detrimental impacts on a range of

fisheries and wildlife resources as well as the petroleum infrastructure that exists

throughout the basin, resulting in a detrimental impact to the communities

dependent on those resources.

5.15.3.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.3.2.1 Direct

Since there are no communities on the barrier islands, implementation of

Alternative 5 will have no direct impact on community cohesion.

5.15.3.2.2 Indirect

Since there are no communities on the barrier islands, implementation of

Alternative 5 will have no indirect impact on community cohesion.

5.15.3.2.3 Cumulative

The cumulative impact of the NER Plan on community cohesion would be positive.

By slowing wetland loss and retaining the protective function of the barrier islands

communities dependent on the basin resources would be less likely to lose cohesion

and community identity.

5.15.3.3 Alternative 11: Whiskey (Plan C)

5.15.3.3.1 Direct

There is no community residing within the Study Area, and the proposed action

would have no direct impacts outside the Study Area.

5.15.3.3.2 Indirect

There is no community residing within the Study Area, and the proposed action

would have no indirect impacts outside the Study Area.

5.15.3.3.3 Cumulative

There is no community residing within the Study Area, and the proposed action

would have no cumulative impacts outside the Study Area.

5.15.3.4 Alternative 2: Timbalier (Plan E)

5.15.3.4.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.3.4.2 Indirect

Indirect impacts would be similar to Alternative 11.

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5.15.3.4.3 Cumulative

The restoration and renourishment of Timbalier Island at TY30 will continue to

afford protection to the petroleum transmission and processing facilities behind the

island, which will have a positive impact on community cohesion.

5.15.3.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.3.5.1 Direct

Since there are no communities on the barrier islands, implementation of

Alternative 3 will have no direct impact on community cohesion.

5.15.3.5.2 Indirect

Since there are no communities on the barrier islands, implementation of

Alternative 3 will have no indirect impact on community cohesion.

5.15.3.5.3 Cumulative

Cumulative impacts would be similar to Alternative 2.

5.15.3.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.3.6.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan), but of reduced scope,

since it only involves three islands.

5.15.3.6.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan), but of reduced scope,

since it only involves three islands.

5.15.3.6.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan), but of reduced

scope, since it only involves three islands.

5.15.4 Environmental Justice

5.15.4.1 No Action Alternative (Future without Project Conditions)

5.15.4.1.1 Direct

There would be no direct impact of the No Action Alternative on environmental

justice, as this concept is inapplicable within the Study Area. The Study Area is

undeveloped and uninhabited.

5.15.4.1.2 Indirect

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There would be no indirect impact of the No Action Alternative on environmental

justice, as this concept is inapplicable within the Study Area. The Study Area is

undeveloped and uninhabited.

5.15.4.1.3 Cumulative

There would be no cumulative impact of the No Action Alternative on

environmental justice, as this concept is inapplicable within the Study Area. The

Study Area is undeveloped and uninhabited.

5.15.4.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.4.2.1 Direct

There would be no direct impact of Alternative 5 (NER Plan) on environmental

justice, as this concept is inapplicable within the Study Area. The Study Area is

undeveloped and uninhabited.

5.15.4.2.2 Indirect

There would be no indirect impact of Alternative 5 (NER Plan) on environmental

justice, as this concept is inapplicable within the Study Area. The Study Area is

undeveloped and uninhabited.

5.15.4.2.3 Cumulative

There would be no cumulative impact of Alternative5 (NER Plan) on environmental

justice, as this concept is inapplicable within the Study Area. The Study Area is

undeveloped and uninhabited).

5.15.4.3 Alternative 11: Whiskey (Plan C)

5.15.4.3.1 Direct

There would be no direct impact of Alternative 11 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.3.2 Indirect

There would be no indirect impact of Alternative 11 on environmental justice, as

this concept is inapplicable within the Study Area. The Study Area is undeveloped

and uninhabited.

5.15.4.3.3 Cumulative

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There would be no cumulative impact of Alternative 11 on environmental justice, as

this concept is inapplicable within the Study Area. The Study Area is undeveloped

and uninhabited.

5.15.4.4 Alternative 2: Timbalier (Plan E)

5.15.4.4.1 Direct

There would be no direct impact of Alternative 2 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.4.2 Indirect

There would be no indirect impact of Alternative 2 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.4.3 Cumulative

There would be no cumulative impact of Alternative 2 on environmental justice, as

this concept is inapplicable within the Study Area. The Study Area is undeveloped

and uninhabited.

5.15.4.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.4.5.1 Direct

There would be no direct impact of Alternative 3 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.5.2 Indirect

There would be no indirect impact of Alternative 3 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.5.3 Cumulative

There would be no cumulative impact of Alternative 3 on environmental justice, as

this concept is inapplicable within the Study Area. The Study Area is undeveloped

and uninhabited.

5.15.4.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.4.6.1 Direct

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There would be no direct impact of Alternative 4 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.6.2 Indirect

There would be no indirect impact of Alternative 4 on environmental justice, as this

concept is inapplicable within the Study Area. The Study Area is undeveloped and

uninhabited.

5.15.4.6.3 Cumulative

There would be no cumulative impact of Alternative 4 on environmental justice, as

this concept is inapplicable within the Study Area. The Study Area is undeveloped

and uninhabited.

5.15.5 Infrastructure

The Terrebonne Basin Barrier Islands have no public infrastructure, such as

streets, potable water supply and distribution, and wastewater collection and

treatment. The islands are uninhabited and undeveloped and inaccessible except by

boat or aircraft. Private infrastructure exists throughout the Terrebonne Basin in

the form of oil and gas wells, transmission lines, and petroleum distribution,

storage, and processing facilities

5.15.5.1 No Action Alternative (Future without Project Conditions)

5.15.5.1.1 Direct

The Study Area is remote and uninhabited. The existing private infrastructure

includes oil and gas pipelines; storage tank batteries, platforms, and wellheads. The

effects of continued barrier island loss and degradation will lead to increased costs

for maintenance and repair of the existing infrastructure, reduced level of oil and

gas infrastructure development, and possible relocation of some existing oil and gas

assets.

5.15.5.1.2 Indirect

The indirect impacts of the No Action Alternative will be the same as the direct

impacts, because the private infrastructure is scattered throughout the Terrebonne

Basin in open water and on other islands and remaining marsh areas. As the

barrier islands disappear these areas will become increasingly vulnerable, resulting

in the same impacts.

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5.15.5.1.3 Cumulative

The cumulative impact will be the same as the direct and indirect as the basins

islands and wetlands deteriorate and shift to open water.

5.15.5.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.5.2.1 Direct

Implementing the NER Plan would provide protection to the private infrastructure

on and adjacent to the four islands. Due to the planned renourishment events, this

protection should last for the duration of the 50-year period of analysis.

5.15.5.2.2 Indirect

Indirect impacts would be similar to the direct impacts of Alternative 5 (NER) but

expanded to the infrastructure located to the north in open water and on the other

islands in Terrebonne Bay.

5.15.5.2.3 Cumulative

Cumulative impacts would be similar to the indirect impacts, as long as the

proposed renourishment events are undertaken.

5.15.5.3 Alternative 11: Whiskey (Plan C)

5.15.5.3.1 Direct

Implementing this single island alternative would provide protection to the existing

infrastructure in the immediate area of Whiskey Island, assuming the proposed

renourishment events are undertaken in TY20 and TY40. Appropriate safety

precautions will be implemented for this and all other alternatives to avoid

potential construction-related impacts to existing infrastructure (e.g., pipelines,

wellheads, etc.).

5.15.5.3.2 Indirect

Implementing this single island alternative would have no indirect impacts on

existing infrastructure beyond the immediate area of Whiskey Island.

5.15.5.3.3 Cumulative

Implementing this single island alternative would have no cumulative impacts on

existing infrastructure beyond the immediate area of Whiskey Island.

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5.15.5.4 Alternative 2: Timbalier (Plan E)

5.15.5.4.1 Direct

Implementing this single island alternative would provide protection to the

extensive existing infrastructure in the immediate area of Timbalier Island,

assuming the renourishment event is undertaken in TY30. Appropriate safety

precautions will be implemented for this and all other alternatives to avoid

potential construction-related impacts to existing infrastructure (e.g., pipelines,

wellheads, etc.).

5.15.5.4.2 Indirect

Implementing this single island alternative would have no indirect impacts on

existing infrastructure beyond the immediate area of Timbalier Island.

5.15.5.4.3 Cumulative

Implementing this single island alternative would have no cumulative impacts on

existing infrastructure beyond the immediate area of Timbalier Island.

5.15.5.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.5.5.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan) but of lesser benefit

because Alternative 3 only involves two islands, however, as pointed out above,

Timbalier Island has extensive oil and gas industry infrastructure that would be

protected

5.15.5.5.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan), but of lesser benefit

because Alternative 3 only involves two islands.

5.15.5.5.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan), but of lesser

benefit because Alternative 3 only involves two islands.

5.15.5.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.5.6.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan) but of lesser benefit

because Alternative 4 only involves three islands, however, as pointed out above,

Timbalier Island has extensive oil and gas industry infrastructure that would be

protected.

5.15.5.6.2 Indirect

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Indirect impacts would be similar to Alternative 5 (NER Plan), but of somewhat

lesser benefit because Alternative 4 only involves three islands.

5.15.5.6.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan), but of somewhat

lesser benefit because Alternative 4 only involves three islands. As mentioned

previously, the cumulative benefits will only be realized if the proposed

renourishment events occur in the target years indicated.

5.15.6 Business and Industry

5.15.6.1 No Action Alternative (Future without Project Conditions)

5.15.6.1.1 Direct

The Study Area is remote and uninhabited. The primary industry in the Study Area

involves oil and gas extraction, processing, and transmission. Also of considerable

economic importance in the Terrebonne Basin are the commercial fisheries for

shrimp, finfish, and oysters. The effects of continued barrier island loss and

degradation will lead to increased maintenance costs for existing oil and gas

infrastructure, reduced level of oil and gas infrastructure development, and

relocation of some existing oil and gas assets. The no-action alternative would not

have any immediate direct impact on commercial fisheries. Existing conditions will

persist. The continued loss of wetland habitat within the Study Area and the

Terrebonne Basin, combined with the ongoing widespread wetland loss throughout

coastal Louisiana, will contribute to an overall decrease in productivity of

Louisianas coastal fisheries. The target species for the fisheries are estuarydependent species. As the estuaries and the marshes diminish in area and

productivity, their ability to provide shelter and forage for those species also

diminishes.

5.15.6.1.2 Indirect

The indirect impacts of the No Action Alternative will be the same as the direct

impacts, because the industrial infrastructure is scattered throughout the

Terrebonne Basin in open water and on other islands and remaining marsh areas.

As the barrier islands disappear these areas will become increasingly vulnerable,

resulting in the same impacts. The indirect impact to the commercial fishery

businesses will result from the gradual decline in abundance of the target resources

which will require adjustment to other target species or relocation to other more

productive fishing grounds. This adjustment could be unavoidable, if the regulatory

agencies conclude that the resources have exceeded their maximum sustainable

yield and close the fishery.

5.15.6.1.3 Cumulative

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The cumulative impacts of the No Action Alternative will be the same as the

indirect impacts, because the industrial infrastructure is scattered throughout the

Terrebonne Basin in open water and on other islands and remaining marsh areas.

As the barrier islands disappear these areas will become increasingly vulnerable,

resulting in the same impacts. Cumulative impacts to commercial fisheries in the

Study Area will be the same as the indirect impacts.

5.15.6.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.6.2.1 Direct

The direct impacts of implementing the NER Plan will provide protection to the

industrial infrastructure on and adjacent to the four islands. Due to the planned

renourishment events, this protection should last for the duration of the 50-year

period of analysis. Restoration of the barrier islands and their associated marshes

will slow the deterioration of the interior wetlands by affording them protection

against direct storm damage. In addition the restored marshes will continue to

provide the shelter and nursery functions required by the estuary-dependent fishery

resources.

5.15.6.2.2 Indirect

The indirect impacts will be similar to the direct impacts because the industrial

infrastructure is scattered throughout the Terrebonne Basin, as are the fishery

resources and the marshes and other wetlands upon which they depend for shelter

and forage.

5.15.6.2.3 Cumulative

The cumulative impacts will be similar to the direct and indirect impacts.

5.15.6.3 Alternative 11: Whiskey (Plan C)

5.15.6.3.1 Direct

Whiskey Island does not protect any industrial infrastructure, so the direct impact

of its restoration will be negligible. However, restoration of the marsh and its

protective beach and dune will provide a benefit to the fishery resources similar to

Alternative 5 (NER Plan), but at a reduced scale.

5.15.6.3.2 Indirect

The indirect impacts of implementing Alternative 11 will be similar to the direct

impacts.

5.15.6.3.3 Cumulative

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The cumulative impacts of implementing Alternative 11 will be similar to the direct

impacts.

5.15.6.4 Alternative 2: Timbalier (Plan E)

5.15.6.4.1 Direct

The direct impacts of implementing Alternative 2 would be similar to Alternative

11. In addition, Timbalier Island protects a significant amount of industrial

infrastructure from direct impact from the Gulf of Mexico and, similarly to Whiskey

Island, the restored marsh and its protective beach and dune will provide a benefit

to fishery resources, due to the proposed renourishment at TY30.

5.15.6.4.2 Indirect

As a single island restoration, the indirect impacts would be similar to the direct

impacts.

5.15.6.4.3 Cumulative

The cumulative impacts would be similar to the direct and indirect impacts,

providing localized benefits to industrial infrastructure and fisheries resources, but

minimal far-field benefits.

5.15.6.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.6.5.1 Direct

The direct impacts would be similar to Alternative 5 (NER Plan) but of lesser

benefit because Alternative 3 only involves two islands. However, as pointed out

above, Timbalier Island has extensive industrial infrastructure that would be

protected.

5.15.6.5.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan), but of lesser benefit

because Alternative 3 only involves two islands. Assuming the proposed

renourishment of Whiskey Island at TY20 and TY40, plus the renourishment of

Timbalier Island at TY30, the restored beach, dune, and marsh components on each

island will provide benefit to the fishery resources in the vicinity of both islands.

5.15.6.5.3 Cumulative

The cumulative impacts would be similar to the direct and indirect impacts,

providing localized benefits to industrial infrastructure and fisheries resources, but

minimal far-field benefits.

5.15.6.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.6.6.1 Direct

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Direct impacts would be similar to Alternative 5 (NER Plan), but somewhat reduced

because they will be derived from only three islands.

5.15.6.6.2 Indirect

Indirect impacts would be similar to the direct benefits.

5.15.6.6.3 Cumulative

Cumulative impacts would be similar to the direct and indirect benefits.

5.15.7 Traffic and Transportation

5.15.7.1 No Action Alternative (Future without Project Conditions)

5.15.7.1.1 Direct

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by shoal-draft boat or aircraft. There is no public or private

transportation infrastructure. There would be no direct impacts of the No Action on

traffic and transportation, as this feature does not exist within the Study Area

5.15.7.1.2 Indirect

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by shoal-draft boat or aircraft. There is no public or private

transportation infrastructure. There would be no indirect impacts of the No Action

Alternative on traffic and transportation, as this feature does not exist within the

Study Area

5.15.7.1.3 Cumulative

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by shoal-draft boat or aircraft. There is no public or private

transportation infrastructure. There would be no cumulative impacts of the No

Action Alternative on traffic and transportation, as this feature does not exist

within the Study Area

5.15.7.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.7.2.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.7.2.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.7.2.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

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5.15.7.3 Alternative 11: Whiskey (Plan C)

5.15.7.3.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.7.3.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.7.3.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.7.4 Alternative 2: Timbalier (Plan E)

5.15.7.4.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.7.4.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.7.4.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.7.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.7.5.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.7.5.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.7.5.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.7.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.7.6.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.7.6.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.7.6.3 Cumulative

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Cumulative impacts would be the same as the No Action Alternative.

5.15.8 Public Facilities and Services

5.15.8.1 No Action Alternative (Future without Project Conditions)

5.15.8.1.1 Direct

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities or public

services on the islands. There would be no direct impacts of the No Action

Alternative on public facilities and services, as these features do not exist within

the Study Area. Five of the islands, Raccoon, Whiskey, and Trinity/East, Wine

Islands, are owned and managed as a wildlife refuge by the LDWF, however, there

are no LDWF facilities present.

5.15.8.1.2 Indirect

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities or public

services on the islands. There would be no indirect impacts of the No Action

Alternative on public facilities and services, as these features do not exist within

the Study Area. Five of the islands, Raccoon, Whiskey, Trinity/East, and Wine

Islands, are managed as a wildlife refuge by the LDWF, however, there are no

LDWF facilities present.

5.15.8.1.3 Cumulative

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities or public

services on the islands. There would be no cumulative impacts of the No Action

Alternative on public facilities and services, as these features do not exist within

the Study area. Five of the islands, Raccoon, Whiskey, Trinity/East, and Wine

Islands, are managed as a wildlife refuge by the LDWF, however, there are no

LDWF facilities present.

5.15.8.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.8.2.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.8.2.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.8.2.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

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5.15.8.3 Alternative 11: Whiskey (Plan C)

5.15.8.3.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.8.3.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.8.3.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.8.4 Alternative 2: Timbalier (Plan E)

5.15.8.4.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.8.4.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.8.4.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.8.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.8.5.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.8.5.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.8.5.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.8.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.8.6.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.8.6.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.8.6.3 Cumulative

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Cumulative impacts would be the same as the No Action Alternative.

5.15.9 Local Government Finance

5.15.9.1 No Action Alternative (Future without Project Conditions)

5.15.9.1.1 Direct

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by shoal-draft boat or aircraft. There are no local

government expenditures for public services on the islands. There would be no

direct impacts of the No Action Alternative on local government finance, as this

aspect of government services is not applicable within the Study Area.

5.15.9.1.2 Indirect

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by shoal-draft boat or aircraft. There are no local

government expenditures for public services on the islands. There would be no

indirect impacts of the No Action Alternative on local government finance, as this

aspect of government services is not applicable within the Study Area.

5.15.9.1.3 Cumulative

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by shoal-draft boat or aircraft. There are no local

government expenditures for public services on the islands. There would be no

cumulative impacts of the No Action Alternative on local government finance, as

this aspect of government services is not applicable within the Study Area.

5.15.9.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.9.2.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.9.2.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.9.2.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.9.3 Alternative 11: Whiskey (Plan C)

5.15.9.3.1 Direct

Direct impacts would be the same as the No Action Alternative.

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5.15.9.3.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.9.3.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.9.4 Alternative 2: Timbalier (Plan E)

5.15.9.4.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.9.4.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.9.4.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.9.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.9.5.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.9.5.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.9.5.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.9.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.9.6.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.9.6.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.9.6.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.10 Tax Revenue and Property Values

The LDWF owns the surface rights to Whiskey Island and Raccoon Island. Mineral

rights are privately-owned. LDWF owns the surface rights to the majority of Trinity

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Island/East Island. Approximately 30 acres appear to be privately-owned. It

appears that this private landowner also owns the underlying mineral rights. The

LDWF also owns the majority of Timbalier Island. There appears to be 11 privatelyowned tracts on the eastern end of the island as well as private underlying mineral

right holders.

5.15.10.1 No Action Alternative (Future without Project Conditions)

5.15.10.1.1 Direct

The direct impact of the No Action Alternative would be the disappearance of all of

the islands before the end of the century. There would be no taxable property

remaining.

5.15.10.1.2 Indirect

The indirect impact of the No Action Alternative would be the disappearance of all

of the islands before the end of the century. There would be no taxable property

remaining.

5.15.10.1.3 Cumulative

The cumulative impact of the No Action Alternative would be the disappearance of

all of the islands before the end of the century. There would be no taxable property

remaining.

5.15.10.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.10.2.1 Direct

The direct impact of implementing the NER Plan, with proposed renourishments,

would be to preserve some taxable value of the four islands to the end of the 50-year

period of analysis.

5.15.10.2.2 Indirect

The indirect impact to Wine and East Timbalier islands would be a continuation of

their existing rate of erosion until they disappear, along with any taxable value.

5.15.10.2.3 Cumulative

The cumulative impact would be similar to the indirect impact.

5.15.10.3 Alternative 11: Whiskey (Plan C)

5.15.10.3.1 Direct

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The direct impact of implementing Alternative 11, with proposed renourishments,

would be to preserve some taxable value of the single island to the end of the 50-

year period of analysis.

5.15.10.3.2 Indirect

The indirect impact to the remaining islands would be a continuation of their

existing rate of erosion until they disappear, along with any taxable value.

5.15.10.3.3 Cumulative

The cumulative impact would be similar to the indirect impact.

5.15.10.4 Alternative 2: Timbalier (Plan E)

5.15.10.4.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.10.4.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.10.4.3 Cumulative

Cumulative impacts would be similar to Alternative 11.

5.15.10.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.10.5.1 Direct

The direct impact of implementing Alternative 3, with proposed renourishments,

would be to preserve some taxable value for both islands to the end of the 50-year

period of analysis.

5.15.10.5.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.10.5.3 Cumulative

The cumulative impacts would be similar to the indirect impact.

5.15.10.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.10.6.1 Direct

The direct impact of implementing Alternative 4, with proposed renourishments,

would be to preserve some taxable value of the three islands to the end of the 50-

year period of analysis.

5.15.10.6.2 Indirect

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Indirect impacts would be similar to Alternative 11.

5.15.10.6.3 Cumulative

Cumulative impacts would be similar to the indirect impact.

5.15.11 Community and Regional Growth

5.15.11.1 No Action Alternative (Future without Project Conditions)

5.15.11.1.1 Direct

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There would be no direct impacts of the

No Action Alternative on community and regional growth, as these features do not

exist within the Study Area.

5.15.11.1.2 Indirect

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There would be no indirect impacts of

the No Action Alternative on community and regional growth, as these features do

not exist within the Study Area.

5.15.11.1.3 Cumulative

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There would be no cumulative impacts of

the No Action Alternative on community and regional growth, as these features do

not exist within the Study Area.

5.15.11.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.11.2.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.11.2.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.11.2.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.11.3 Alternative 11: Whiskey (Plan C)

5.15.11.3.1 Direct

Direct impacts would be the same as the No Action Alternative.

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5.15.11.3.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.11.3.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.11.4 Alternative 2: Timbalier (Plan E)

5.15.11.4.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.11.4.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.11.4.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.11.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.11.5.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.11.5.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.11.5.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.11.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.11.6.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.11.6.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.11.6.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12 Land Use Socioeconomics

Agriculture

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5.15.12.1 No Action Alternative (Future without Project Conditions)

5.15.12.1.1 Direct

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities on the

islands. No agricultural or forestry-related activities are supported. There would be

no direct impacts of the No Action Alternative on agriculture or silviculture land

use, as these uses do not exist within the Study Area.

5.15.12.1.2 Indirect

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities on the

islands. No agricultural or forestry-related activities are supported. There would be

no indirect impacts of the No Action Alternative on agriculture or silviculture land

use, as these uses do not exist within the Study Area.

5.15.12.1.3 Cumulative

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities on the

islands. No agricultural or forestry-related activities are supported. There would be

no cumulative impacts of the No Action Alternative on agriculture or silviculture

land use, as these uses do not exist within the Study Area.

5.15.12.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.12.2.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.2.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.2.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.3 Alternative 11: Whiskey (Plan C)

5.15.12.3.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.3.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

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5.15.12.3.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.4 Alternative 2: Timbalier (Plan E)

5.15.12.4.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.4.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.4.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.12.5.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.5.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.5.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.12.6.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.6.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.6.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

Forestry

5.15.12.7 No Action Alternative (Future without Project Conditions)

5.15.12.7.1 Direct

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The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities on the

islands. No agricultural or forestry-related activities are supported. There would be

no direct impacts of the No Action Alternative on agriculture or silviculture land

use, as these uses do not exist within the Study Area.

5.15.12.7.2 Indirect

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities on the

islands. No agricultural or forestry-related activities are supported. There would be

no indirect impacts of the No Action Alternative on agriculture or silviculture land

use, as these uses do not exist within the Study Area.

5.15.12.7.3 Cumulative

The Study Area consists of two reaches of a chain of remote, uninhabited barrier

islands, accessible only by boat or aircraft. There are no public facilities on the

islands. No agricultural or forestry-related activities are supported. There would be

no cumulative impacts of the No Action Alternative on agriculture or silviculture

land use, as these uses do not exist within the Study Area.

5.15.12.8 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.12.8.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.8.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.8.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.9 Alternative 11: Whiskey (Plan C)

5.15.12.9.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.9.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.9.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

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5.15.12.10 Alternative 2: Timbalier (Plan E)

5.15.12.10.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.10.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.10.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.11 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.12.11.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.11.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.11.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

5.15.12.12 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.12.12.1 Direct

Direct impacts would be the same as the No Action Alternative.

5.15.12.12.2 Indirect

Indirect impacts would be the same as the No Action Alternative.

5.15.12.12.3 Cumulative

Cumulative impacts would be the same as the No Action Alternative.

Public Lands

5.15.12.13 No Action Alternative (Future without Project Conditions)

5.15.12.13.1 Direct

There would be no direct impacts of the No Action Alternative on public lands

within the Study Area. Not implementing barrier restoration features would result

in the persistence of existing conditions.

5.15.12.13.2 Indirect

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The indirect impacts on public lands in the region that would most likely be affected

under the No Action Alternative are those related to the loss of wetlands and

habitat diversity.

As wetland degradation and the high rates of land loss continues throughout the

area, wildlife abundance would continue to decrease. The local abundance of

resident transitional wetland-dependent wildlife would likely decrease. These

species would have to relocate to find more suitable transitional wetland habitats.

Migratory birds would be required to find other, more suitable stopover habitats on

their trans-Gulf migrations. With the continued conversion of transitional

estuarine wetlands to open water, estuarine fishery abundance and diversity would

be expected to decline over time. Lower quality fishery spawning, nursery, and

foraging habitat would translate to a decline in sport fishing success in the future

as the usage by game species decline, so would the hunting opportunities and the

usage by migratory birds decline, so would the opportunities for viewing.

5.15.12.13.3 Cumulative

Cumulative impacts would be the synergistic effect of the No-Action Alternative on

public lands with the additive combination of similar impacts from wetland loss and

degradation throughout coastal Louisiana on public lands, as well as the benefits

and impacts of other State and Federal projects in the vicinity.

5.15.12.14 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.12.14.1 Direct

The primary direct impacts on public lands would result from the Study Area being

temporarily unavailable during construction. In addition, there would be a

temporary decrease in the quality of recreational opportunities as the wetland

creation and nourishment sites re-vegetates, usually within 9 to 12 months,

following completion of construction.

5.15.12.14.2 Indirect

Alternative 5 (NER Plan) would protect, create and nourish transitional estuarine

wetlands. Following construction, these transitional estuarine wetlands would

provide important and essential fish and wildlife habitats that would contribute to

restoring the base of organisms used for recreational activities such as fishing and

camping. Increased recreation activities and public land use would come from

expansion of new vegetative habitat on newly created areas and the relief from

flooding frequency stressors that those areas would afford existing habitats.

5.15.12.14.3 Cumulative

Cumulative impacts would be the synergistic effect of implementing Alternative 5

(NER Plan) with the additive combination of impacts and benefits for overall net

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acres created, nourished, and protected by other Federal, State, local, and private

restoration efforts. Alternative 5 (NER Plan) would work synergistically with those

projects to provide more complete protection for barrier islands, which would

continue to provide wetland-dependent recreational opportunities on public lands

within the Study Area.

5.15.12.15 Alternative 11: Whiskey (Plan C)

5.15.12.15.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.15.12.15.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.15.12.15.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.15.12.16 Alternative 2: Timbalier (Plan E)

5.15.12.16.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.15.12.16.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.15.12.16.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.15.12.17 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.12.17.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.15.12.17.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.15.12.17.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.15.12.18 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.12.18.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

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5.15.12.18.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.15.12.18.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.15.13 Water Use and Supply

5.15.13.1 No Action Alternative (Future without Project Conditions)

5.15.13.1.1 Direct

The Terrebonne Basin Barrier Islands have no public infrastructure, such as

streets, potable water supply and distribution, and wastewater collection and

treatment. The islands are uninhabited and undeveloped and inaccessible except by

boat or aircraft. There would be no direct impacts of the No Action Alternative on

water use and water supply, as these features do not exist within the Study Area.

5.15.13.1.2 Indirect

The Terrebonne Basin Barrier Islands have no public infrastructure, such as

streets, potable water supply and distribution, and wastewater collection and

treatment. The islands are uninhabited and undeveloped and inaccessible except by

boat or aircraft. There would be no indirect impacts of the No Action Alternative on

water use and water supply, as these features do not exist within the Study Area.

5.15.13.1.3 Cumulative

The Terrebonne Basin Barrier Islands have no public infrastructure, such as

streets, potable water supply and distribution, and wastewater collection and

treatment. The islands are uninhabited and undeveloped and inaccessible except by

boat or aircraft. There would be no cumulative impacts of the No Action Alternative

on water use and water supply, as these features do not exist within the Study

Area.

5.15.13.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.13.2.1 Direct

There would be no direct impact on the water supplies in this area.

5.15.13.2.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.15.13.2.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

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5.15.13.3 Alternative 11: Whiskey (Plan C)

5.15.13.3.1 Direct

There would be no direct impact on the water supplies in this area.

5.15.13.3.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.15.13.3.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.15.13.4 Alternative 2: Timbalier (Plan E)

5.15.13.4.1 Direct

There would be no direct impact on the water supplies in this area.

5.15.13.4.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.15.13.4.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.15.13.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.13.5.1 Direct

There would be no direct impact on the water supplies in this area.

5.15.13.5.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.15.13.5.3 Cumulative

There would be no cumulative impact on the water supplies in this area.

5.15.13.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.13.6.1 Direct

There would be no direct impact on the water supplies in this area.

5.15.13.6.2 Indirect

There would be no indirect impact on the water supplies in this area.

5.15.13.6.3 Cumulative

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There would be no cumulative impact on the water supplies in this area.

5.15.14 Navigation

The two reaches of Terrebonne Basin Barrier Islands, the Isles Dernieres and

Timbalier Reaches, are bisected by the Houma Navigation Canal, which empties

into the Gulf of Mexico at Cat Island Pass, between Trinity-East and Timbalier

Islands. The HNC is a Federal channel, maintained by the New Orleans District of

the USACE. Elsewhere in the Basin there are numerous privately-maintained and

marked channels, where safe navigation depends solely on local knowledge.

5.15.14.1 No Action Alternative (Future without Project Conditions)

5.15.14.1.1 Direct

The No Action Alternative, not implementing the barrier island restoration

features, would have no immediate direct impacts on navigation in the Study Area.

5.15.14.1.2 Indirect

Indirect impacts would result from the persistence of existing conditions, including

continued degradation of the barrier islands, loss of their associated wetlands, and

loss of interior wetlands north of the Study Area. This continued wetland loss may

affect navigability and maintenance of both the federally- and privately-maintained

waterways, including the Houma Navigation Canal and several smaller bayous.

5.15.14.1.3 Cumulative

The cumulative impact of the No Action Alternative could change access, cost, and

frequency of maintenance for the federally maintained waterways that transect

Terrebonne and Timbalier Bays and pass near the Study Area.

5.15.14.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.14.2.1 Direct

The direct impact from implementing the NER Plan would be temporary disruption

of recreational and commercial vessel traffic in the vicinity of each island during

construction.

5.15.14.2.2 Indirect

The direct impact from implementing the NER Plan would be temporary disruption

of recreational and commercial vessel traffic in the vicinity of each island during

construction.

5.15.14.2.3 Cumulative

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Cumulative impacts, assuming the proposed renourishment events occur, would be

a reduction in the impact on waterway shoaling and waterway maintenance costs.

5.15.14.3 Alternative 11: Whiskey (Plan C)

5.15.14.3.1 Direct

The direct impact of implementing the recommended component of construction

would be temporary disruption of vessel traffic in the vicinity of the island during

construction.

5.15.14.3.2 Indirect

The indirect impact of implementing the recommended component of construction

would be temporary disruption of vessel traffic in the vicinity of the dredge at the

borrow area.

5.15.14.3.3 Cumulative

Implementing this alternative would have a cumulative impact on commercial and

recreational vessel traffic by some undetermined level during construction along the

barrier islands being restored.

5.15.14.4 Alternative 2: Timbalier (Plan E)

5.15.14.4.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.14.4.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.14.4.3 Cumulative

Cumulative impacts would be similar to Alternative 11.

5.15.14.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.14.5.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.14.5.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.14.5.3 Cumulative

Cumulative impacts would be similar to Alternative 11.

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5.15.14.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.14.6.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.14.6.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.14.6.3 Cumulative

Cumulative impacts would be similar to Alternative 11.

5.15.15 Man-Made Resources

Oil, Gas, Utilities, Pipelines

5.15.15.1 No Action Alternative (Future without Project Conditions)

5.15.15.1.1 Direct

The mineral-rich subsurface of the Terrebonne Basin has significantly contributed

to the States thriving oil and gas industry. According to the SONRIS database,

there are a total of 1,109 wells, 12 pipelines, and 396 pits found in the vicinity of the

Study Area (LDNR 2009). The No Action Alternative would have no direct impacts

on oil and gas activities or infrastructure since there will be no disturbance to the

island footprints or the borrow areas.

5.15.15.1.2 Indirect

Pipeline crossings occur within the island footprints, between the islands, and

within the vicinity of the islands. These pipelines are used to transport oil crude

and natural gas from wells to facilities scattered throughout the Terrebonne Basin.

As previously stated, there are a total of 12 oil and gas pipelines within the Study

Area, eleven of which are currently active. Table 5-10 presents active oil and gas

pipelines in or near the islands (LDNR 2009). There are also numerous pipelines that

intersect the proposed borrow areas.

Table 5-10. Pipelines in the Vicinity of the Study Area*

Pipeline ID Company Status Location

1498 United Gas Pipeline Company Active East Timbalier

2778 Duke Energy Hydrocarbons, LLC Active East Timbalier

3604 Chevron Pipeline Co. Active East Timbalier

3043 Tennessee Gas Transmission Company Active East Timbalier

5796 \ 5797 California Oil Company Abandoned East Timbalier

2567 Equilon Pipeline Company, LLC Active Western Portion of Timbalier

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Pipeline ID Company Status Location

9882 Louisiana Offshore Gathering S Active Eastern Portion of Timbalier

6138 Comstock Offshore, LLC Active Between East and Wine Islands

9145 Bayou City Pipelines, INC Active Between Whiskey and Trinity Islands

3860 Williams Field Service Co. Active East of Raccoon Island

7602 Trunkline Gas Company Active West of Raccoon Island

*These pipelines represent the active oil and gas pipelines that were identified in the SONRIS

database (LDNR, 2009). Additional investigations, including field verification, will be conducted

during PED to refine this list

Indirect impacts of not implementing wetland creation/nourishment and shoreline

protection features would result in the persistence of existing conditions including

the fragmentation and degradation of the existing barrier islands and inland

marshes. The unimpeded erosion of these areas will continue to uncover pipelines

that have been buried both on the islands and on the seafloor. As these pipelines

are exposed, they will become susceptible weathering, boat collisions, and impacts

from anchor dragging. Furthermore, erosion of the sediments surrounding the

pipelines could compromise the structural integrity of the pipelines and their

associated infrastructure. Damage to oil and gas pipelines could potentially result

in releases of petroleum products to the environmental. This will not only have a

considerable environmental impact, but will also have an impact on production. In

addition, cleanup costs could be substantial.

Timbalier and East Timbalier Islands are the only two islands in the Study Area

that host active oil and gas facilities. These facilities include a combination of

active and inactive wells, platforms, tank batteries, housing infrastructure, and

pits. Continued erosion of the beaches and dunes could eventually expose these

facilities to direct hurricane impacts. This could potentially result in spills,

damaged to infrastructure, and lost revenues.

5.15.15.1.3 Cumulative

The combined, incremental effects of the No Action alternative and the continued

degradation of Louisianas barrier coastline could have a significant adverse impact

on the oil and gas infrastructure in the Study Area over the 50-year period of

analysis. These impacts include exposure of the pipelines and infrastructure to

direct hurricane forces and navigational hazards. Although existing State and

Federal restoration projects within or near the Study Area will help to lessen these

impacts, they are not sufficient to reverse the process.

5.15.15.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.15.2.1 Direct

Although there are numerous pipelines within the Study Area, Timbalier Island is

the only island in the NER Plan with pipelines that are located within the proposed

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template. The construction of the NER Plan will benefit these pipelines by further

covering them will fill material. This will provide a protective barrier from

weather-related impacts as well as impacts associated with the day-to-day

operation of the oil and gas facilities. During PED, these pipelines will be clearly

marked so that they are not damaged while dredging the back-barrier access

channels.

The pipelines running through the Ship Shoal, South Pelto, Whiskey 3a, New Cut,

and Raccoon borrow areas could be directly impacted during the sediment mining

activities. However, these impacts are highly unlikely because the pipelines will be

clearly identified during PED. Also, a buffer zone will be applied to each pipeline to

provide additional protection during construction. Contractors will not be allowed

to dredge within the buffer zone.

5.15.15.2.2 Indirect

As previously stated, the NER Plan will benefit the existing pipelines on Timbalier

Island by providing additional protection from impacts. This could potentially

reduce the susceptibility of the pipelines to petroleum releases. The indirect

benefits of pipeline protection include a reduction in environmental risks (petroleum

impacts on wildlife and habitat) and economic risks (downtime, lost product, spill

cleanup costs). Furthermore, the oil and gas facilities on Timbalier Island will

indirectly benefit from the additional protection provided by the restored dune and

beaches that are gulfward of the facilities.

Oil and gas infrastructure within the bays and on the mainland behind Raccoon,

Whiskey, Trinity, and Timbalier Island would also benefit from the additional storm

surge and wave protection afforded by the restored islands.

There are no relocations of pipelines or oil and gas infrastructure associated with

construction or renourishment of the NER Plan.

5.15.15.2.3 Cumulative

When compared to the No Action Alternative, the combined, incremental effects of

the NER Plan and the existing coastal restoration projects within or adjacent to the

Study Area are expected to provide additional protection for the oil and gas

pipelines and infrastructure over the 50-year period of analysis.

5.15.15.3 Alternative 11: Whiskey (Plan C)

5.15.15.3.1 Direct

There are no oil and gas pipelines or infrastructure located within the proposed

template for Whiskey Island Plan C. Therefore, placement of fill on the island will

not have any direct impacts on oil and gas activities.

The pipelines running through the Ship Shoal and Whiskey 3 borrow areas could be

directly impacted during the sediment mining activities. However, as with the NER

Plan, these impacts are highly unlikely because the pipelines will be clearly

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identified during PED. Also, a buffer zone will be applied to each pipeline to

provide additional protection during construction. Contractors will not be allowed

to dredge within the buffer zone.

5.15.15.3.2 Indirect

Oil and gas infrastructure within the bays and on the mainland behind Whiskey

Island will indirectly benefit from the recommended component of construction

since the restoration features will provide enhanced protection from storm surge

and wave impacts. There are no relocations of pipelines or oil and gas

infrastructure associated with construction or renourishment of the recommended

component of construction.

5.15.15.3.3 Cumulative

When compared to the No Action Alternative, the combined, incremental effects of

the recommended component of construction and the existing coastal restoration

projects within or adjacent to the Study Area are expected to provide additional

protection for the oil and gas pipelines and infrastructure over the 50-year period of

analysis. However, the level of protection provided by the recommended component

of construction will be less than that provided by the NER Plan since only one

island is being restored.

5.15.15.4 Alternative 2: Timbalier (Plan E)

5.15.15.4.1 Direct

Construction of Timbalier Plan E will directly benefit the two active pipelines that

are on the island by further covering them will fill material. This will provide a

protective barrier from weather-related impacts as well as impacts associated with

the day-to-day operation of the oil and gas facilities. During PED, these pipelines

will be clearly marked so that they are not damaged while dredging the backbarrier access channels.

The pipelines running through the South Pelto and Whiskey 3a borrow areas could

be directly impacted during the sediment mining activities. However, these impacts

are highly unlikely because the pipelines will be clearly identified during PED.

Also, a buffer zone will be applied to each pipeline to provide additional protection

during construction. Contractors will not be allowed to dredge within the buffer

zone.

5.15.15.5 Indirect

Construction of Timbalier Plan E could potentially reduce the susceptibility of the

two existing pipelines on the island to petroleum releases. This wood translate to a

reduction in environmental risks (petroleum impacts on wildlife and habitat) and

economic risks (downtime, lost product, spill cleanup costs). Furthermore, the oil

and gas facilities on Timbalier Island will indirectly benefit from the additional

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protection provided by the restored dune and beaches that are gulfward of the

facilities. There are no relocations of pipelines or oil and gas infrastructure

associated with construction or renourishment of Alternative 2.

5.15.15.5.1 Cumulative

When compared to the No Action Alternative, the combined, incremental effects of

Alternative 2 and the existing coastal restoration projects within or adjacent to the

Study Area are expected to provide additional protection for the oil and gas

pipelines and infrastructure over the 50-year period of analysis. The cumulative

hydrologic impacts of Alternative 2 would be greater than that of the recommended

component of construction (a smaller island plan), but less than that of the NER

Plan (a four-island plan).

5.15.15.6 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.15.6.1 Direct

There is no oil and gas infrastructure on Whiskey Island. Construction of Timbalier

Plan E, however, will directly benefit the two active pipelines that are on the island

by further covering them with fill material and providing a protective barrier.

The pipelines running through the Ship Shoal, South Pelto, Whiskey 3a, and

Raccoon borrow areas could be directly impacted during the sediment mining

activities. However, these impacts are highly unlikely because the pipelines will be

clearly identified during PED. Also, a buffer zone will be applied to each pipeline to

provide additional protection during construction. Contractors will not be allowed

to dredge within the buffer zone.

5.15.15.6.2 Indirect

As with Alternative 2, construction of Timbalier Plan E could potentially reduce the

susceptibility of the two existing pipelines on the island to petroleum releases. This

would translate to a reduction in environmental and economic risks. Furthermore,

the oil and gas facilities on Timbalier Island will indirectly benefit from the

additional protection provided by the restored dune and beaches that are gulfward

of the facilities. Oil and gas infrastructure within the bays and on the mainland

behind Whiskey Island would also benefit from the additional storm surge and wave

protection afforded by the restored islands.

There are no relocations of pipelines or oil and gas infrastructure associated with

construction or renourishment of Alternative 3.

5.15.15.6.3 Cumulative

When compared to the No Action Alternative, the combined, incremental effects of

Alternative 3 and the existing coastal restoration projects within or adjacent to the

Study Area are expected to provide additional protection for the oil and gas

pipelines and infrastructure over the 50-year period of analysis. The cumulative

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hydrologic impacts of Alternative 3 would be greater than that of Alternative 2 (a

one-island plan), but less than that of the NER Plan (a four-island plan).

5.15.15.7 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.15.7.1 Direct

There is no oil and gas infrastructure on Whiskey or Trinity Island. Construction of

Timbalier Plan E, however, will directly benefit the two active pipelines that are on

the island by further covering them with fill material and providing a protective

barrier.

The pipelines running through the Ship Shoal, South Pelto, Whiskey 3a, New Cut,

and Raccoon borrow areas could be directly impacted during the sediment mining

activities. However, these impacts are highly unlikely because the pipelines will be

clearly identified during PED and will be protected with a buffer.

5.15.15.7.2 Indirect

The indirect benefits of Alternative 4 would be very similar to Alternative 3.

Construction of Timbalier Plan E could potentially reduce the susceptibility of the

two existing pipelines on the island to petroleum releases. This would translate to a

reduction in environmental and economic risks. Furthermore, the oil and gas

facilities on Timbalier Island will indirectly benefit from the additional protection

provided by the restored dune and beaches that are gulfward of the facilities. Oil

and gas infrastructure within the bays and on the mainland behind Whiskey and

Trinity Island would also benefit from the additional storm surge and wave

protection afforded by the restored islands.

There are no relocations of pipelines or oil and gas infrastructure associated with

construction or renourishment of Alternative 4.

5.15.15.7.3 Cumulative

When compared to the No Action Alternative, the combined, incremental effects of

Alternative 4 and the existing coastal restoration projects within or adjacent to the

Study Area are expected to provide additional protection for the oil and gas

pipelines and infrastructure over the 50-year period of analysis. The cumulative

hydrologic impacts of Alternative 4 would be greater than that of Alternative 3 (a

two-island plan), but less than that of the NER Plan (a four-island plan).

Flood Control and Hurricane Protection

5.15.15.8 No Action Alternative (Future without Project Conditions)

5.15.15.8.1 Direct

The Study Area is remote and uninhabited. There are no flood control or hurricane

protection levees in the area. The No Action Alternative would have no direct

impact. The existing trends, including continued wetland loss and degradation of

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the barrier islands, would persist, with the islands becoming increasingly

vulnerable to storm surge overwash and erosion.

5.15.15.8.2 Indirect

Without any action, approximately 2,811 acres of existing barrier resources from

the seven island Terrebonne Basin barrier system (East Timbalier, Timbalier,

Trinity, East Island, Wine, Whiskey and Raccoon Island) would likely continue to

deteriorate, degrade, fragment and eventually convert into shallow open water

bottoms. If the Terrebonne Basin barrier island system is not restored, the adjacent

estuarine bay systems, along with the interior coastal marshes, will continue to be

transformed into marine open water habitat.

5.15.15.8.3 Cumulative

There would be no cumulative impacts of the No Action Alternative on flood control

or hurricane protection levees, as this resource does not exist within the Study

Area. However, modeling studies conducted by Stone, et al. (2005) have

demonstrated that loss of the barrier islands and associated oyster reefs has had,

and will continue to have, a significant effect on wave heights in the adjacent bays

and their fringing marshes. Not implementing barrier restoration features will

result in the persistence of island erosion and wetland loss, both on the islands and

in the bays to the north.

5.15.15.9 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.15.9.1 Direct

The direct impact of implementing the NER Plan on flood control is not an

applicable issue, because there are no flood control levees in the Study Area.

Regarding hurricane protection, the proposed minimum island design restoration

template retains island geomorphic form and ecologic function and prevents

breaching when subjected to the impacts of two pairs of historic hurricanes

(Katrina/Rita and Gustav/Ike) and a theoretical 50-year storm. The proposed

template will add sufficient width and elevation to the islands for them to survive

similar hurricanes.

5.15.15.9.2 Indirect

The indirect impacts of implementing the NER Plan would be an undetermined

reduction in wave height in the bays to the north (Lake Pelto and Terrebonne and

Timbalier Bays), and a concomitant reduction in marsh and bay island erosion. The

NER Plan would also reduce storm surge to some degree further north in the

Terrebonne Basin and potentially reduce the storm surge-related stresses placed

upon existing and planned flood control structures.

5.15.15.9.3 Cumulative

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Cumulative impacts would be a combination of the above-referenced direct and

indirect impacts, assuming the proposed renourishment events occur.

5.15.15.10 Alternative 11: Whiskey (Plan C)

5.15.15.10.1 Direct

Implementing this alternative would have the direct impact of protecting the

restored Whiskey Island beach, dune, and marsh from storm surges and erosion.

5.15.15.10.2 Indirect

Implementing this alternative would have an undetermined indirect impact of

protecting the adjacent wetlands of Lake Pelto from storm surges and erosion.

Alternative 11 would also provide storm surge-related benefits, albeit to a lesser

degree than the NER Plan.

5.15.15.10.3 Cumulative

Implementing this alternative, assuming the proposed renourishment events occur,

would have the cumulative impact of providing an undetermined level of protection

for Whiskey Island and the nearby wetlands of Lake Pelto from storm surges and

erosion. Increasing and maintaining the restored acreage would contribute to a

reduction of storm surge and wave heights in the area.

5.15.15.11 Alternative 2: Timbalier (Plan E)

5.15.15.11.1 Direct

Direct impacts of implementing Alternative 2 would be similar to Alternative 11.

5.15.15.11.2 Indirect

The indirect impacts for Timbalier Island would be similar to those for Whiskey

Island, Alternative 11.

5.15.15.11.3 Cumulative

The cumulative impacts would be similar to Alternative 11, however the storm

surge and wave height reductions would not be as significant, because the wetlands

to the north are at a greater distance.

5.15.15.12 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.15.12.1 Direct

The direct impacts would be a combination of Alternatives 11 (recommended

component of construction) and Alternative 2.

5.15.15.12.2 Indirect

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The indirect impacts would be a combination of Alternatives 11 (recommended

component of construction) and Alternative 2.

5.15.15.12.3 Cumulative

The cumulative impacts would be a combination of Alternatives 11 (recommended

component of construction) and Alternative 2.

5.15.15.13 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.15.13.1 Direct

The direct impacts would be similar to Alternative 5 (NER Plan), but reduced in

scale because the alternative involves only three islands.

5.15.15.13.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan), but reduced in scale

because the alternative involves only three islands.

5.15.15.13.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan), but reduced in

scales because the alternative .involves only thee islands.

5.15.16 Natural Resources

Commercial Fisheries

5.15.16.1 No Action Alternative (Future without Project Conditions)

5.15.16.1.1 Direct

The No Action Alternative, not implementing barrier island restoration features,

would have no direct impacts on commercial fisheries. Existing conditions would

persist. The continued wetland habitat losses within the Study Area, combined

with widespread coastal wetland loss throughout coastal Louisiana, would

contribute to the overall decrease in productivity of Louisianas coastal fisheries.

Louisiana provides more fishery landings than any other State in the conterminous

United States (more than 1.1 billion pounds/year), and more than 75% of

Louisiana's commercially harvested fish and shellfish species are dependent on

wetlands (LSU, http://lamer.lsu.edu/projects/ oceancommotion/facts.htm).

5.15.16.1.2 Indirect

Wetland habitat losses in the Study Area would contribute to the overall decrease

in productivity of these fisheries throughout coastal Louisiana. For example,

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menhaden and other finfish species, shrimp, and blue crabs all depend upon the

estuaries for critical stages in their life cycles.

As much as 16% of the nation's fisheries' harvests, including shrimp, crabs, crawfish, oysters,

and numerous finfish species, come from Louisiana's coast

(http://lamer.lsu.edu/projects/oceancommotion/facts.htm). The seafood industry would

likely suffer significant losses in employment as estuaries that are necessary to produce shrimp,

oysters, and other valuable species continue to diminish in area and in productivity. Job losses

would likely occur in the areas reliant on fishing, harvesting, processing, and shipping of the

seafood catch.

5.15.16.1.3 Cumulative

The seafood industry would likely suffer significant losses in employment and

revenue as the estuarine natural resources, which are necessary to produce shrimp,

oysters, and other valuable species, continue to erode. Job losses would occur in the

areas of fishing, harvesting, processing, and shipping of seafood catch.

5.15.16.2 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.16.2.1 Direct

The direct impact from implementing the NER Plan would be temporary disruption

of commercial fishing vessel traffic in the vicinity of each island during construction.

5.15.16.2.2 Indirect

The indirect impact from implementing the NER Plan would be a temporary

disruption of commercial fishing vessel traffic in the vicinity of the dredge over the

borrow area during construction.

5.15.16.2.3 Cumulative

The cumulative impact from implementing the NER Plan, assuming the proposed

renourishment events occur, would be a reduction in the rate of decline of the

productivity of the estuary, leading to a reduction in the rate of decline of the

fisheries resources.

5.15.16.3 Alternative 11: Whiskey (Plan C)

5.15.16.3.1 Direct

Implementing this alternative would have a short term direct impact on commercial

fishing activity within the Study Area during the period of construction. The

seafood industry would have to operate away from the construction area and would

suffer a temporary loss of revenue until the disruption on marine life is abated.

5.15.16.3.2 Indirect

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Implementing this alternative would have an indirect impact on commercial fishing

activity in the vicinity of the dredge over the borrow area during the period of

construction.

5.15.16.3.3 Cumulative

The cumulative impact of implementing this alternative would be derived from the

additional productive marsh area created and from the adjacent marsh areas

protected from storm damage by the restored and renourished island. Assuming

that the other barrier islands continue to erode throughout the period of analysis,

this single islands impact is probably negligible.

5.15.16.4 Alternative 2: Timbalier (Plan E)

5.15.16.4.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.16.4.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.16.4.3 Cumulative

Cumulative impacts would be similar to Alternative 11, without the referenced

protection afforded the adjacent wetland.

5.15.16.5 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.16.5.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.16.5.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.16.5.3 Cumulative

Cumulative impacts would be similar to Alternative 11.

5.15.16.6 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.16.6.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.15.16.6.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

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5.15.16.6.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

Oyster Leases

Oysters feed by filtering suspended material, including organic detritus and

phytoplankton, from the water that flows past them. The loss of estuarine wetlands

not only reduces detritus, which is used directly by oysters, but also reduces

generation of catabolic substances (i.e. produced by catabolism, a process by which

complex organic molecules are converted to more simple compounds) that are more

readily utilized by primary producers (e.g., phytoplankton), which are then

consumed by oysters and other organisms (Kilgen and Dugas 1989). Oyster larvae

depend on estuaries for protection and food until they settle out of the water column

onto a hard substrate.

5.15.16.7 No Action Alternative (Future without Project Conditions)

5.15.16.7.1 Direct

The No Action Alternative, not implementing barrier island restoration features,

would have no immediate direct impacts on oyster leases. Existing conditions would

persist.

5.15.16.7.2 Indirect

The ongoing loss of wetlands in the Study Area would alter the detritus-based food

web of the oyster thereby reducing the localized carrying capacity of the oyster

leases in the area.

5.15.16.7.3 Cumulative

Cumulative impacts would be eventual loss of barrier and wetland habitats, which

in turn, would result in increased salinity conditions and decreased food supply,

making these areas unsuitable for the viable culture of oysters.

5.15.16.8 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.15.16.8.1 Direct

The immediate direct impacts to oyster leases would include disturbance to water

bottoms from the placement of dredged material. Other direct impacts during

construction would include disturbance and/or mortality due to increased turbidity

and decreased dissolved oxygen from increased biological oxygen demand (BOD).

Once construction is completed the direct impact of implementing the NER Plan

would be stabilization of the barrier islands, thus providing additional sheltered

habitat for oyster settlement, and creation of additional marsh habitat, leading to

increased production of detritus and catabolic compounds.

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5.15.16.8.2 Indirect

The immediate indirect impact to oyster leases could be increased stress from

turbidity generated by the restoration construction. Following completion of

construction, the indirect impact would be the increased production of detritus and

catabolic compounds, which are carried by tidal flow to adjacent areas, thus

benefiting neighboring oyster lease areas.

5.15.16.8.3 Cumulative

The cumulative impact of implementing the NER Plan, assuming the proposed

renourishment events occur, would be a continuation and expansion of the postconstruction indirect impact to a larger area of the Terrebonne Basin for the course

of the period of analysis.

5.15.16.9 Alternative 11: Whiskey (Plan C)

5.15.16.9.1 Direct

The direct impacts to oyster leases would be the same as the NER Plan, applied to a

single island.

5.15.16.9.2 Indirect

There would be minimal, localized indirect impacts to oyster leases in areas

adjacent to the construction area, due to increased turbidity and siltation caused by

fill placement.

5.15.16.9.3 Cumulative

The cumulative impact of this alternative would be similar to that for the NER

Plan, at a scale applicable to a single island.

5.15.16.10 Alternative 2: Timbalier (Plan E)

5.15.16.10.1 Direct

Direct impacts would be similar to Alternative 11.

5.15.16.10.2 Indirect

Indirect impacts would be similar to Alternative 11.

5.15.16.10.3 Cumulative

Cumulative impacts would be similar to Alternative 11.

5.15.16.11 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.15.16.11.1 Direct

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Direct impacts would be similar to Alternative 11 but increased in scale to account

for two islands.

5.15.16.11.2 Indirect

Indirect impacts would be similar to Alternative 11 but increased in scale to account

for two islands.

5.15.16.11.3 Cumulative

Cumulative impacts would be similar to Alternative 11 but increased in scale to

account for two islands.

5.15.16.12 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.15.16.12.1 Direct

Direct impacts would be similar to Alternative 11 but increased in scale to account

for three islands.

5.15.16.12.2 Indirect

Indirect impacts would be similar to Alternative 11, but increased in scale to

account for three islands.

5.15.16.12.3 Cumulative

Cumulative impacts would be similar to Alternative 11, but increased in scale to

account for three islands.

5.16 HAZARDOUS, TOXIC, AND RADIOACTIVE WASTES

[Phase I Environmental Site Assessment Findings]

5.16.1.1 No Action Alternative (Future without Project Conditions)

5.16.1.2 Direct

Based on current and historical uses of the Study Area for oil and gas exploration

and development, there is reason to believe that the potential to encounter HTRW

problems would be moderate. Furthermore, increased susceptibility of oil and gas

infrastructure to coastal processes could increase the potential for HTRW within the

Study Area.

5.16.1.2.1 Indirect

The condition with the No-Action Alternative regarding the potential for HTRW is

dependent on site-specific HTRW discovery. Based on previous HTRW studies in

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the Study Area, there is reason to believe that the potential to encounter HTRW

problems would be moderate.

5.16.1.2.2 Cumulative

The condition with the No-Action Alternative regarding the potential for HTRW is

dependent on site-specific HTRW discovery. Based on previous HTRW studies in

the Study Area, there is reason to believe that the potential to encounter HTRW

problems would be moderate.

5.16.1.3 Alternative 5 (NER Plan): Raccoon w/TG (Plan E) / Whiskey (Plan C) /

Trinity (Plan C) / Timbalier (Plan E)

5.16.1.3.1 Direct

An HTRW investigation of the Study Area was conducted. Based upon findings

from this investigation, there are several petroleum pipelines in the area, but as

long as they are not damaged the potential for direct impacts to the Study Area

from implementation of Alternative 5 (NER Plan) would be low and would likely

continue to be low into the future.

5.16.1.3.2 Indirect

An HTRW investigation of the Study Area was conducted. Based upon findings

from this investigation, there are several petroleum pipelines in the area, but as

long as they are not damaged the potential for indirect impacts to the Study Area

from implementation of Alternative 5 (NER Plan) would be low and would likely

continue to be low into the future.

5.16.1.3.3 Cumulative

An HTRW investigation of the Study Area was conducted. Based upon findings

from this investigation, there are several petroleum pipelines in the area, but as

long as they are not damaged the potential for cumulative impacts to the Study

Area from implementation of Alternative 5 (NER Plan) would be low and would

likely continue to be low into the future.

5.16.1.4 Alternative 11: Whiskey (Plan C)

5.16.1.4.1 Direct

An HTRW investigation of the Study Area was conducted. Based upon findings

from this investigation, there are several petroleum pipelines in the area, but as

long as they are not damaged the potential for direct impacts to the Study Area

from implementation of Alternative 11 would be low and would likely continue to be

low into the future.

5.16.1.4.2 Indirect

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An HTRW investigation of the Study Area was conducted. Based upon findings

from this investigation, there are several petroleum pipelines in the area, but as

long as they are not damaged the potential for indirect impacts to the Study Area

from implementation of Alternative 11 would be low and would likely continue to be

low into the future.

5.16.1.4.3 Cumulative

An HTRW investigation of the Study Area was conducted. Based upon findings

from this investigation, there are several petroleum pipelines in the area, but as

long as they are not damaged the potential for cumulative impacts to the Study

Area from implementation of Alternative 11 would be low and would likely continue

to be low into the future.

5.16.1.5 Alternative 2: Timbalier (Plan E)

5.16.1.5.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.16.1.5.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.16.1.5.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.16.1.6 Alternative 3: Whiskey (Plan C) / Timbalier (Plan E)

5.16.1.6.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.16.1.6.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

5.16.1.6.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

5.16.1.7 Alternative 4: Whiskey (Plan C) / Trinity (Plan C) / Timbalier (Plan E)

5.16.1.7.1 Direct

Direct impacts would be similar to Alternative 5 (NER Plan).

5.16.1.7.2 Indirect

Indirect impacts would be similar to Alternative 5 (NER Plan).

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5.16.1.7.3 Cumulative

Cumulative impacts would be similar to Alternative 5 (NER Plan).

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6.0 PUBLIC INVOLVEMENT

6.1 NEPA SCOPING

The USACE published a Notice of Intent (NOI) to prepare a Supplemental

Environmental Impact Statement (SEIS) for the LCA Terrebonne Basin Barrier

Shoreline Restoration Feasibility Study (Terrebonne Basin Barrier Shoreline

Restoration Study) in the Federal Register (volume 73, number 246) on December

22, 2008.

The purpose of the NOI was to announce the USACE intention to prepare a SEIS

that addresses the LCA TBBSR Study, which was identified in the 2004 LCA

Ecosystem Restoration Plan as a near-term critical restoration project.

NEPA requires an early and open public process for determining the scope of issues,

resources, impacts, and alternatives to be addressed in an EIS. This process is

referred to as scoping. Scoping meeting announcements were advertised in three

area newspapers before the meeting date. The meeting was held on Tuesday,

February 10, 2009, in Houma, Louisiana.

NEPA affords all persons, organizations and government agencies the right to

review and comment on proposed major Federal actions that are evaluated by a

NEPA document. This is known as the scoping process. The scoping process is the

initial step in the preparation of the EIS and will help identify (1) the range of

actions (project, procedural changes), (2) alternatives (both those to be rigorously

explored and evaluated and those that may be eliminated), and (3) the range of

environmental resources considered in the evaluation of environmental impacts.

A scoping meeting announcement requesting comments regarding the scope of the

Terrebonne Basin Barrier Shoreline Restoration Study was sent to Federal, State,

and local agencies; and interested groups and individuals on January 7, 2009. The

media advisory announcing the scoping meeting was provided to 350 media outlets,

and an advertisement for the public scoping meeting appeared in the following

publications:

 The Times-Picayune, January 31, 2009 and February 7, 2009

 The Baton Rouge Advocate, January 31, 2009

 The Houma Courier, January 29, 2009 and February 9, 2009

The public scoping meeting was held on:

Tuesday, February 10, 2009

Houma Municipal Auditorium

880 Verrett St.

Houma, LA 70360

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The schedule for the scoping meeting was:

6:00  7:00 p.m. Open House

7:00  7:30 p.m. Presentations

7:30  8:00 p.m. Question and Answer Session

8:00  8:50 p.m. Open Forum for Comments

8:50  9:00 p.m. Wrap-up

The open house session provided attendees with an opportunity to visit a series of

poster stations staffed by project team members and subject matter experts

regarding the following topics:

 LCA plan

 NEPA process and milestones

 Overview of the study and its goals and objectives

 Maps of the Study Area

Following the open house, there was a brief presentation on the LCA TBBSR Study

planned for the area and a description of the NEPA process. During this segment,

the LCA Environmental Manager and both the USACE Project Managers and the

Coastal Protection and Restoration Authority presented introductory remarks,

including the agenda, purpose of the meeting, public involvement under NEPA, a

brief history leading to the study, the scope of the analysis, and the intent to

prepare a Final EIS for the LCA TBBSR Study.

The question and answer portion focused on explaining the study process and

responding to general questions presented by meeting attendees. Following this

portion, the floor was opened for scoping comments. Individuals were invited to

present their verbal and/or written scoping comments to be recorded without

interruption. This portion of the meeting continued until no further scoping

comments were offered.

During the wrap-up, attendees were reminded to pick up self mailing comment

cards if they wished to submit additional comments at a later date, and to drop off

the meeting evaluation forms at the registration table.

6.2 SCOPING COMMENTS

Scoping and public comments document the publics concerns about the scope of the

proposed course of action and identify significant resources and suggested

alternatives. Scoping comments will be considered during the study process and in

preparation of the SEIS. A total of 45 participants signed in for the scoping meeting

in Houma, Louisiana.

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A total of 22 multi-part comments were received during the comment period. Nine

individuals expressed comments at the Houma scoping meeting. A total of 13

written comments were received during the comment period. There were two

scoping comment cards, five scoping comment letters and six scoping comment emails. There were no scoping comments submitted via the Web site for this study.

A scoping comment may contain several specific comments directed at multiple

areas of concern. Hence, a single comment could potentially be addressed in

multiple sections of the SEIS. A total of 74 specific comments were expressed.

The comments were categorized according to their applicability to the SEIS. SEIS

categories include:

 Purpose and Need

 Alternatives

 Affected Environment

 Environmental Consequences

 Consultation, Coordination, and Compliance with Regulations

An individual scoping comment may be categorized under more than one SEIS

subject matter heading, but no one comment was assigned to more than three

categories.

Purpose and Need

The majority of comments received in this category stressed the need to protect the

barrier islands in the area: Our barrier islands are our first line of defense both for

storm surge protection and protection of the estuaries. This is the first study that

focuses strictly on our barrier island chain from Belle Pass westward over for the

Terrebonne and Lafourche or Lafourche Basin barrier island chain and everybody

wants this project (USACE, 2009). Several respondents stressed the urgency of

project implementation.

Alternatives

Using Ship Shoal sand and/or rock material in the restoration efforts was the most

common suggestion, closely followed by reducing the width of the passes. We are a

proponent of using rock protection to the greatest extent possible, marsh creation and

reduction in the width of the passes. Concerns regarding cost of Ship Shoal sand

were raised Regarding the use of Ship Shoal sand, Ive heard its the best in

southern Louisiana. It would be great to use it, but we probably shouldnt wait until

we can afford Ship Shoal sand. We might be better off mining sand on the back bays,

Timbalier Bay and Lake Pelto, as weve done in the past (USACE, 2009).

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Affected Environment

The most common concern raised regarding affected environment was the need to

include Wine Island in the restoration effort Wine Island, which is now submerged

slightly, is not part of your project. That 6-mile gap is significant and should be part

of the project. Another commonly raised suggestion was to narrow passages to

lower water velocity Environmentally we would be better off with narrow passes

and deeper passes, short of doing anything to the north. Because the Barataria Pass

next to Grand Isle, we have maintained the width. Now it is probably 70 or 80 ft deep

right at the pass, because theres a lot of volume of water that goes in and out from

the Barataria Basin. The passes from Belle Pass eastward are choked down by rocks

(USACE, 2009).

Environmental Consequences

Few comments could be exclusively classified as relating to environmental

consequences, but several concerns were raised regarding the issue of saltwater

intrusion. The St. Louis Canal should not have been dammed. We no longer get

fresh water from the Intracoastal Waterway to flush salt water south, out of Hope

Farm and Point-Aux-Chenes (USACE, 2009)

Consultation, Coordination, and Compliance with Regulations

Concerns regarding urgency of project implementation dominated the comments

received. We ask that this project be addressed with the greatest sense of urgency

due to the importance of hurricane protection and our disappearing wetlands

(USACE, 2009). One commenter was worried this Study would be implemented too

late.

6.2.1 Landowner Involvement

Louisiana Department of Wildlife and Fisheries (LDWF) currently own the Isle

Dernieres Islands as well as the majority of Timbalier Island. LDWF has provided

insight on the Study Area and participated fully in all public meetings.

6.2.2 Non-Governmental Organization (NGO) Involvement

Restore or Retreat (ROR) is a non-profit coastal advocacy group created by coastal

Louisiana residents and stakeholders who recognize that the Barataria and

Terrebonne basins are the two most rapidly eroding estuaries on earth, and that

this erosion represents an economic and ecological crisis. ROR has attended the

LCA Scoping meetings stakeholder meetings, and the CZM Meeting held December

2009 concerning Terrebonne Basin and has commented on the Study area and the

opportunities that lie ahead.

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6.2.3 Parish Involvement

Terrebonne Coastal Zone Management (CZM) was developed by Terrebonne Parish

residents to protect, preserve, enhance, and where possible, restore renewable

resources of the coastal wetlands for the enjoyment and long-term benefit of parish

residents. Terrebonne Coastal Zone Management Committee (CZM) has attended

the LCA Scoping meetings as well as a CZM Meeting in December 2009 concerning

Terrebonne Basin and has commented on the Study area and the opportunities that

lie within.

6.3 PUBLIC COMMENTS ON THE SUPPLEMENTAL EIS

The Supplemental EIS was released to the public in June 2010, and included a 45-

day public review period. A public meeting soliciting comments on the proposed

action presented in the SEIS was held during the public comment period.

Comments from this review period have been incorporated into the final EIS. The

final EIS was released for a 30-day public review period in October 2010.

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7.0 COORDINATION AND COMPLIANCE

This chapter documents the coordination and compliance efforts for this Study

regarding statutory authorities including: environmental laws, regulations,

executive orders, policies, rules, and guidance. Consistency of the NER Plan and

the recommended component of construction with other Louisiana coastal

restoration efforts is also addressed. A summary of the Relevant Federal Statutory

Authorities and Executive Orders is provided in Tables 7-1 and 7-2.

7.1 USACE PRINCIPLES AND GUIDELINES (P&G)

The guidance for conducting Civil Works planning studies (ER 1105-2-100) is based

on the P&G adopted by the Water Resources Council. The P&G are composed of

two parts: The Economic and Environmental Principles and Guidelines for Water

and Related Land Implementation Studies and the Economic and Environmental

Guidelines for Water and Related Land Resources Implementation Studies. The

P&G require the systematic formulation of alternative plans to ensure all

reasonable alternatives are evaluated. The P&G also include guidance on the

development and structure of the studies and reports for projects requiring specific

authorization.

Under the study guidance for projects requiring specific authorization, the

feasibility study requirements include documentation of the planning process and

environmental compliance. The feasibility report is required to document the

planning process and all assumptions made during plan formulation along with the

rationale for decision making. The report should culminate in a recommended plan

along with documentation of how the plan relates to the NED, NER Plan, or a

combined NED/NER Plan. If the project deviates from those plans, the degree and

reasons for the deviation must be documented. The feasibility study is also

required to document compliance with applicable environmental laws and

regulations which can be included as an Environmental Assessment (EA) or EIS

included with the feasibility study or an integrated feasibility study document with

NEPA information.

Planning for this feasibility study has been conducted in accordance with the ER

1105-2-100 guidance. This report is an integrated feasibility study and final EIS.

Policy reviews have been conducted to ensure compliance with applicable USACE

policies.

7.2 ENVIRONMENTAL COORDINATION AND COMPLIANCE

7.2.1 U.S. Fish and Wildlife Coordination Act

The USACE and the USFWS have formally committed to work together to conserve,

protect, and restore fish and wildlife resources while ensuring environmental

sustainability of our Nations water resources under the January 22, 2003,

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Partnership Agreement for Water Resources and Fish and Wildlife. Accordingly, in

a letter dated May 9, 2005, the USFWS indicated agreement to serve as a

Cooperating Agency (per NEPA section 1501.6) in developing the final EIS for the

proposed project in accordance with applicable NEPA and CEQ guidance.

Participation of the USFWS includes: 1) participating in meetings and field trips to

obtain baseline information on project-area fish and wildlife resources; 2)

evaluating the proposed projects impacts to wetlands and associated fish and

wildlife resources, and assisting in the development of measures to avoid, minimize,

and/or compensate for those impacts; and 3) providing technical assistance in the

development of a Biological Assessment describing the impacts of the proposed

activity to Federally listed threatened or endangered species and/or their critical

habitat.

Prior to the current Study, the USFWS partnered with various other State, local,

and Federal agencies and entities in preparing the Programmatic Environmental

Impact Statement (PEIS) on the LCA Comprehensive Coastwide Ecosystem

Restoration Study. In a letter date September 26, 2003, the USFWS responded to a

request by the Corps to provide the listed threatened and endangered species, their

critical habitat, and migratory birds that may be found in or near the LCA TBBSR

Study Area (LCA, 2004).

In a letter dated January 21, 2010, the USFWS provided specific guidance on

including subtidal habitat in Study Area calculation. The letter also requested

Barrier Island Wetland Value Assessment V1, V2, and V3 Values for all new

alternatives that were added to the Final Array of Alternatives. Lastly, the letter

notified the Corps that potential impacts to the threatened piping plover

(Charadrius melodus) and/or its critical habitat via dredged material placement on

the islands should be addressed in planning studies and that formal consultation

with USFWS would be necessary if the proposed project directly or indirectly affects

the plover or its critical habitat. The coordination letter is included in Appendix A.

The USACE requested consultation with the USFWS on August 9, 2010. The

request initiated the formal consultation processes that culminated in the issuance

of a USFWS Biological Opinion (Annex A2) on September 23, 2010. The USACE has

agreed to comply with the RPM and the terms and conditions outlined in the

Biological Opinion and summarized in Sections 3.6.7.1 and 3.7.7.1.

On September 17, 2010, the USFWS issued the Final Fish and Wildlife

Coordination Act Report for the LCA TBBSR Study (Appendix B). The final report

contains a description of existing fish and wildlife resources in the Study Area,

discusses future with-project (FWP) and future without-project (FWOP) habitat

conditions, and identifies fish and wildlife-related impacts. The USFWS also

provided 13 recommendations to improve the proposed restoration measures:

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1. The Service, NMFS, and LDWF should be provided an opportunity to review and

submit recommendations on future detailed planning reports and the draft plans

and specifications on the Terrebonne Basin Barrier Shoreline Restoration Project

addressed in this report.

2. Consultation should continue with the Service and NMFS on detailed contract

specifications to avoid and minimize potential impacts to piping plover and their

critical habitat, manatees, sea turtles, migratory birds, and essential fish habitat.

3. Avoid adverse impacts to nesting waterbird colonies through careful design

project features and timing of construction. For colonies containing nesting gulls,

terns, and/or black skimmers, all activity occurring within 650 feet of a rookery

should be restricted to the non-nesting period (i.e., September 16 through April 1,

exact dates may vary within this window depending on species present). For

colonies containing nesting wading birds (i.e., herons, egrets, night-herons, ibis, and

roseate spoonbills), anhingas, and/or cormorants, all activity occurring within 1,000

feet of a rookery should be restricted to the non-nesting period (i.e., September 1

through February 15, exact dates may vary within this window depending on

species present). Prior to any such work, surveys should be conducted by qualified

personnel during the colonial seabird nesting season to determine the presence and

location of any such colonies. In addition, we recommend that on-site contract

personnel be informed of the need to identify colonial nesting birds and their nests,

and should avoid affecting them during the breeding season. Because of the extent

of the proposed restoration we understand that it may not be feasible to conduct all

construction related activities outside of pertinent nesting seasons. Should those

activities overlap with colonial nesting waterbird nesting seasons further

coordination with this office will be necessary.

4. To minimize disturbance to nesting colonies of brown pelicans, all activity

occurring within 2,000 feet of a rookery should be restricted to the non-nesting

period (i.e., September 15 through March 31). Prior to construction activities,

surveys should be conducted by qualified personnel during the brown pelican

nesting season to determine the presence and location ofany such colonies. In

addition, we recommend that on-site contract personnel be informed of the need to

brown pelicans and their nests, and should avoid affecting them during the

breeding season. Because of the extent of the proposed restoration we understand

that it may not be feasible to conduct all construction related activities outside of

pertinent nesting seasons. Should those activities overlap with the brown pelican

nesting season further coordination with this office will be necessary.

5. In order to minimize adverse impacts to blue crabs, we recommend that efforts be

made to prohibit the mining of Ship Shoal during annual periods of highest blue

crab use (i.e., April through October).

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6. If the proposed project has not been constructed within 1 year or if changes are

made to the proposed project, the Corps should re-initiate Endangered Species Act

consultation with the Service.

7. Portions of the proposed project are within the Isles Dernieres Barrier Islands

Refuge. No activities should occur on that refuge without first obtaining a Special

Use Permit from LDWF.

8. The newly created barrier island and back-barrier marsh, as well as the

surrounding habitats that may be indirectly benefited by long-shore transport and

sediment overwash, should be monitored over the project life for effectiveness and

the results should be provided to all resource agencies. Development of those

monitoring plans should be coordinated with all natural resource agencies. In

addition, those monitoring plans should be consistent with the Barrier Island

Comprehensive Monitoring requirements developed by the Office of Coastal

Protection and Restoration under funding from LCA Science and Technology

Program.

9. All dredge material containment features should be breached or degraded, if

necessary to restore tidal connectivity, once the marsh creation/nourishment areas

have at least 80% coverage of emergent vegetation.

10. The Service recommends that the Wine Island "Rock Ring" alternative be reanalyzed for potential inclusion in the NER plan, taking into account qualitative

benefits associated with important foraging, nesting, and roosting areas for federal

trust resources that are not incorporated into the IWR.

11. If authorized funding limits for this project are increased the Service

recommends that the NER plan (with Wine Island design if feasible) be

reconsidered as the potential future SP.

12. If additional dollars become available for constructing further increments of the

NER plan, the Service recommends that the Corps fully coordinate with the natural

resource agencies in prioritizing restoration of those islands contained within the

NER plan that are not within the SP.

13. In addition, to the above recommendations, LDWF believes that hard structures

(such as segmented breakwaters) should be reconsidered for inclusion in the

proposed project if additional funding becomes available. It has been LDWFs

experience that hard structures add considerable longevity to barrier island

restoration projects, offering high value for their cost. Therefore, we recommend

that the COE coordinate with pertinent natural resource agencies regarding the

potential use of hard structures should additional project funding become available.

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The USACE concurred with and adopted all recommendations provided by the

USFWS with the exception of Recommendations No. 10 and 13. The Wine Island

Rock Ring was evaluated and screened during the plan formulation process.

According the results of the CE/ICA analysis, the rock ring was considerably less

cost effective than the other alternatives. The fixed cost associated with pipeline

installation and equipment mobilization/ demobilization could not be justified given

the few AAHUs that would be created by the rock ring alternative.

Segmented breakwaters and other hard structures were evaluated for each island

during the plan formulation process (see Section 3.2.3). With the exception of the

terminal groin on Raccoon Island, the hard structures that were evaluated were

eliminated from further consideration because they either did not meet the initial

screening criteria (Section 3.2.3.1) or because they were not cost effective based on

the CE/ICA analysis. Island-specific evaluations of the breakwaters and terminal

groins are provided in Section 3.2.3.3.

7.2.2 Clean Water Act  Section 401

Section 401 of the Clean Water Act requires the certification of all federal licenses

and permits in which there is a discharge of fill material into navigable

waters. The certification is used to determine whether an activity will impact

established site specific water quality standards. Federal licenses and permits

cannot be issued without a water quality certification. The most common federal

license or permit requiring certification is the USACE 404 permit.

In August 2010, the USACE submitted an application for a Water Quality

Certification to the Louisiana Department of Environmental Quality (DEQ) for the

implementation of the NER Plan. The USACE received a response from DEQ on

September 20, 2010 stating that the requirements for a Water Quality Certification

had been met and that the placement of fill material would not violate water quality

standards of Louisiana as provided for in LAC 33:IX Chapter 11. DEQ further

stated that a Water Quality Certification has been issued to the USACE (number

WQC 100824-03/A1 171484/CER 20100003) for the NER Plan. The Water Quality

Certification letter is provided in Appendix D.

7.2.3 Clean Water Act  Section 404(b)(1)

The USACE is responsible for administering regulations under Section 404(b)(1) of

the Clean Water Act. Potential project-related impacts subject to these regulations,

such as the discharge of dredged material into shallow open water areas to create

wetlands, and the placement of rock for shoreline protection, will been evaluated in

compliance with Section 404(b)(1) of the Clean Water Act. The Section 404(b)(1)

Water Quality Report is included in Appendix D.

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Table 7.1 Relevant Federal Statutory Authorities and Executive Orders

(Note: This list is not complete or exhaustive)

Abandoned Shipwreck Act of 1987

American Indian Religious Freedom Act of 1978

Anadromous Fish Conservation Act of 1965

Archaeological Resources Protection Act of 1979

Archaeological and Historical Preservation Act of

1974

Bald Eagle Protection Act of 1940

Clean Air Act of 1970

Clean Water Act of 1977

Coastal Barrier Improvement Act of 1990

Coastal Barrier Resources Act of 1982

Coastal Wetlands Planning, Protection, and

Restoration Act of 1990

Coastal Zone Management Act of 1972

Coastal Zone Protection Act of 1996

Comprehensive Environmental Response,

Compensation, and Liability Act of 1980

Consultation and Coordination with Indian Tribal

Governments (EO 13175) of 2000

Deepwater Port Act of 1974

Emergency Planning and Community Right-toKnow

Act of 1986

Emergency Wetlands Restoration Act of 1986

Endangered Species Act of 1973

Environmental Quality Improvement Act of 1970

Estuaries and Clean Waters Act of 2000

Estuary Protection Act of 1968

Estuary Restoration Act of 2000

Exotic Organisms (EO 11987) of 1977

Farmland Protection Policy Act of 1981

Federal Actions to Address Environmental Justice

in Minority Populations & Low-Income Populations

(EO 12898, 12948) of 1994, as amended

Federal Compliance with Pollution Control

Standards (EO 12088) of 1978

Federal Emergency Management (EO 12148) of

1979

Federal Water Pollution Control Act of 1972

Federal Water Project Recreation Act of 1965

Fish and Wildlife Conservation Act of 1980

Fish and Wildlife Coordination Act of 1958

Flood Control Act of 1944

Floodplain Management (EO 11988) of 1977

Food Security Act of 1985

Greening of the Government Through Leadership in

Environmental Management (EO 13148) of 2000

Historic Sites Act of 1935

Historical and Archaeological Data-Preservation

Act of 1974

Indian Sacred Sites (EO 13007) of 1996

Invasive Species (EO 13112) of 1999

Land & Water Conservation Fund Act of 1965

Magnuson-Stevens Fishery Conservation and

Management Act of 1976, as amended

Marine Mammal Protection Act of 1972

Marine Protected Areas (EO 13158) of 2000

Marine Protection, Research, and Sanctuaries

Act of 1972

Migratory Bird Conservation Act of 1929

Migratory Bird Treaty Act of 1918

Migratory Bird Habitat Protection (EO 13186) of 2001

National Environmental Policy Act of 1969

National Historic Preservation Act of 1966

National Invasive Species Act of 1996

Native American Graves Protection and

Repatriation Act of 1990

Neotropical Migratory Bird Conservation Act of 2000

Noise Control Act of 1972

Nonindigenous Aquatic Nuisance Prevention and Control

Act of 1996

North American Wetlands Conservation Act of 1989

Oil Pollution Act of 1990

Outer Continental Shelf Lands Act of 1953

Pollution Prevention Act of 1990

Prime or Unique Farmlands, 1980 CEQ

Memorandum

Protection and Enhancement of the Cultural

Environment (EO 11593) of 1971

Protection and Enhancement of Environmental Quality

(EO 11991) of 1977

Protection of Children from Environmental Health Risks

and Safety Issues (EO 13045) of 1997

Protection of Cultural Property (EO 12555) of 1986

Protection of Wetlands (EO 11990) of 1977

Reclamation Projects Authorization and Adjustments Act

of 1992

Recreational Fisheries (EO 12962) of 1995

Resource Conservation and Recovery Act of 1976

Responsibilities of Federal Agencies to Protect Migratory

Birds (EO 13186) of 2001

Rivers and Harbors Acts of 1899, 1956

River and Harbor and Flood Control Act of 1970

Safe Drinking Water Act of 1974

Submerged Land Act of 1953

Sustainable Fisheries Act of 1996

Toxic Substances Control Act of 1976

Uniform Relocation Assistance and Real Property

Acquisition Policies Act of 1970 (Public Law 91-646)

Water Resources Development Acts of 1976, 1986, 1990,

1992, and 2007

Water Resources Planning Act of 1965

Watershed Protection & Flood Prevention Act of 1954

Water Pollution Control Act Amendments of 1961

Wild and Scenic River Act of 1968

Wilderness Act of 1964

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Table 7.2 Relevant State Statutory Authorities (Note: this list is not

complete or exhaustive)

Air Control Act

Archeological Treasury Act of 1974

Louisiana Coastal Resources Program

Louisiana Natural and Scenic Rivers System Act

Louisiana Threatened and Endangered Species and Rare

& Unique Habitats

Protection of Cypress Trees

Water Control Act

7.2.4 Section 122 of the Rivers and Harbors Act

Section 122 of the River and Harbor Flood Control Act of 1970 (PL 91-611) provides

for economic, environmental and social assessments, and requires that the Chief

promulgate guidelines designed to ensure that adverse economic, social and

environmental effects have been fully considered in plan formulation. The following

specific effects have been addressed in the Environmental Consequences section

(Section 5.0):

 Air, noise, water pollution.

 Destruction/disruption of resources, aesthetic values, community cohesion,

etc.

 Adverse employment effects, tax and property values.

 Displacement.

 Disruption of desirable community and regional growth.

7.2.5 Coastal Zone Management Act of 1972

Section 307 of the Coastal Zone Management Act (CZM) of 1972 (16 U.S.C.

1456(c)(1)(A)) directs Federal agencies proposing activities or development projects

(including civil work activities), whether within or outside the coastal zone, must

assure that those activities or projects are consistent, to the maximum extent

practicable, with the approved State coastal zone management program. A

Consistency Determination is included with this report (Appendix E) and was

submitted to the Louisiana Department of Natural Resources (LDNR) for

consistency review. Consistency concurrence was received on August 6, 2010.

Implementation of the NER Plan and the recommended component of construction

has been considered consistent, to the maximum extent practicable, with the

approved Louisiana State coastal management program.

7.2.6 Endangered Species Act of 1973

Compliance with the ESA (7 U.S.C. 136; 16 U.S.C. 460 et seq.) has been coordinated

with the USFWS and the NMFS for those species under their respective

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jurisdictions. The use of recommended primary activity exclusion zones and timing

restrictions would be utilized, to the maximum extent practicable, to avoid project

construction impacts to any threatened or endangered species or their critical

habitat within the Study Area. The USACE will continue to closely coordinate and

consult with the USFWS and the NMFS regarding threatened and endangered

species under their jurisdiction that may be potentially impacted by the proposed

action. Although the West Indian manatee and the Hawksbill, Kemps ridley,

Leatherback, Loggerhead, and Green sea turtles may be found in the Study Area,

the only endangered species with a high potential for adverse impacts from the

NER Plan and the recommended component of construction is the piping plover.

Multi-project research is currently underway to determine the potential for

diversion impacts to this species. Formal consultation on the piping plover has been

conducted and the USFWS has issued a Biological Opinion (Annex A2). The USACE

has agreed to comply with the RPM and the terms and conditions outlined in the

Biological Opinion and summarized in Sections 3.6.7.1 and 3.7.7.1.

The analysis of potential impacts of the NER Plan on endangered species is

described in Section 5.11 - Threatened and Endangered Species. A U.S. Fish and

Wildlife Service Biological Assessment is included in Appendix A.

7.2.7 Magnuson-Stevens Fishery Conservation and Management

Act of 1996; and the Magnuson-Stevens Act

Reauthorization of 2006 (Essential Fish Habitat)

As directed by the Magnuson-Stevens Fishery Conservation and Management Act

(Public Law 104-297), the USACE has coordinated with the NMFS and that

agencys experts on various marine organisms, as well as EFH (letter from NMFS,

2009). Via e-mail on January 13, 2010, the NMFS provided an updated essential

fish habitat guide prepared by the NMFS Southeast Regional Office as well as a

link to the 2004 EIS and the 2005 Generic Amendment to the Fishery Management

Plans which replaces the previously provided 2006 NMFS guidance document.

The NMFS identified shrimp, red drum, reef fish, and stone crabs as species

managed by the Gulf of Mexico Fishery Management Council that have Essential

Fish Habitat (EFH) in the proposed action area. They also listed estuarine

emergent wetlands, mud, sand and shell substrates, and estuarine and marine

water column as primary categories of EFH in the proposed action area. The

analysis of potential impacts of the NER Plan and the recommended component of

construction on EFH is described in Section 5.10 Essential Fish Habitat. The

NOAA Fisheries Service Coordination Letter will be included in Appendix C once it

is received.

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7.2.8 Clean Air Act  Air Quality Determination

Compliance with the Clean Air Act (42 U.S.C.A. §§7401) will be fully coordinated

with the Air Quality Section of the LDEQ (see also Section 5.4 Air Quality). As

required by Louisiana Administrative Code, Title 33 (LAC 33:III.1405 B), an air

quality applicability determination will be made for the NER Plan and the

recommended component of construction. This will include consideration of the

proposed action for the category of general conformity, in accordance with the

Louisiana General Conformity, State Implementation Plan (LDEQ, 1994). An air

quality determination will be calculated, based upon direct and indirect air

emissions. Generally, since no other indirect Federal action, such as licensing or

subsequent actions would likely be required or related to the restoration

construction actions, it is likely that indirect emissions, if they would occur, would

be negligible. Therefore, the air applicability determination analysis will be based

upon direct emission for estimated construction hours. Considering that total

emissions for each work item separately (or even when all work items are summed)

would not exceed the threshold limit applicable to Volatile Organic Compounds

(VOC) for parishes where the most stringent requirement (50 tons per year in

serious non-attainment parishes) is in effect (see General Conformity, State

Implementation Plan, Section 1405 B.2), the VOC emissions for the proposed

construction would be classified as de minimus and no further action would be

required.

7.2.9 National Historic Preservation Act of 1966

Section 106 of the National Historic Preservation Act of 1966 (16 U.S.C. § 470f), as

amended, requires Federal agencies to take into account the effects of their

undertakings on historic properties and afford the Advisory Council on Historic

Preservation (ACHP) a reasonable opportunity to comment on such undertakings.

Pursuant to 36 C.F.R. 800 of the regulations implementing Section 106 of the

National Historic Preservation Act, a Federal agency shall consult with the State

Historic Preservation Officer (SHPO) and any Federally recognized Indian tribe

that attaches religious and cultural significance to such properties. Accordingly,

USACE initiated consultation with the ACHP, SHPO and federally recognized

Indian tribes in May 2009.

In accordance with ER 1105-2-100, Appendix C, paragraph C-4(d)(5)(d)(2), the

USACE elected to fulfill its obligations under Section 106 of the National Historic

Preservation Act of 1966, as amended, through the execution and implementation of

a Programmatic Agreement. In consultation with the ACHP, Louisiana SHPO,

Indian tribes, representatives of local governments, and other consulting parties,

the USACE developed a Programmatic Agreement among the USACE, CPRA,

SHPO, and ACHP, pursuant to 36 CFR § 800.14(b)(1), executed July 29, 2010. The

Programmatic Agreement establishes the procedures for consultation, identification

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of historic properties, assessment and resolution of adverse effects, and is included

in Appendix F.

7.2.10 Farmland Protection Policy Act (Prime and Unique

Farmlands)

The purpose of the Farmland Protection Policy Act (7 U.S.C. 658) is to minimize the

extent to which Federal programs contribute to the unnecessary and irreversible

conversion of farmland to non-agricultural uses. There are no farmlands within the

Study Area. Hence, there would be no unnecessary or irreversible conversion of

farmland to non-agricultural uses.

7.2.11 Executive Order 13186  Migratory Bird Habitat

Protection

Executive Order 13186 proclaims the intent to support the conservation of previous

migratory bird conventions by integrating bird conservation principles, measures,

and practices into agency activities and by avoiding or minimizing, to the extent

practicable, adverse impacts on migratory bird resources when conducting agency

actions. This Executive Order requires environmental analyses of Federal actions

required by the NEPA or other established environmental review processes

evaluate the effects of actions and agency plans on migratory birds, with emphasis

on species of concern. In addition, each Federal agency shall restore and enhance

the habitat of migratory birds, as practicable. Implementation of the NER Plan and

the recommended component of construction would result in a net increase in

migratory bird habitat.

7.2.12 Executive Order 12898  Environmental Justice

Concern with environmental justice issues can be traced to Title VI, Section 601 of

the Civil Rights Act of 1964 (Public Law 88-352):

No person in the United States shall, on the grounds of race, color, or

national origin, be excluded from participation in, be denied the benefits of, or

be subjected to discrimination under any program or activity receiving

Federal financial assistance.

On February 11, 1994, President Clinton issued Executive Order 12898 regarding

Federal actions to address environmental justice issues in minority populations and

low-income populations:

To the greatest extent practicable and permitted by law, and consistent with

the principles set forth in the report on the National Performance Review, each

Federal agency shall make achieving environmental justice part of its mission

by identifying and addressing, as appropriate, disproportionately high and

adverse human health or environmental effects of its programs, policies, and

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activities on minority populations and low-income populations in the United

States and its territories and possessions, the District of Columbia, the

Commonwealth of Puerto Rico, and the Commonwealth of the Mariana

Islands.

Executive Order 12898 is designed to focus Federal attention on the environmental

and human health conditions in minority communities and low-income

communities. The order is also intended to promote non discrimination in Federal

programs substantially affecting human health and the environment, and to

provide minority communities and low income communities access to public

information on, and an opportunity for public participation in, matters relating to

human health or environmental planning, regulations, and enforcement. Potential

environmental justice issues have been considered throughout the entire study

process, and will continue to be considered through project implementation. As part

of the NEPA process, a scoping input request was provided to the public and

interested parties. The four scoping comments did not identify any potential

environmental justice issues. The USACE is committed to ensuring that any

potential environmental justice issues are addressed as the study proceeds. The

proposed wetland creation and nourishment and shoreline protection measures

would equally impact all potential users (e.g., commercial and recreational fishers)

in the area. There would be no potential environmental justice issues from

implementing the NER Plan or the recommended component of construction.

7.2.13 Executive Order 13112  Invasive Species

On February 3, 1999, President Clinton issued Executive Order 13112 to prevent

the introduction of invasive species and provide for their control and to minimize

the economic, ecological, and human health impacts that invasive species cause by

establishing the National Invasive Species Council. The NER Plan and the

recommended component of construction are consistent with Executive Order 13112

to the extent practicable and permitted by law and subject to the availability of

appropriations, and within Administration budgetary limits. The NER Plan and

the recommended component of construction will use relevant programs and

authorities to prevent the introduction of invasive species and not authorize, fund,

or carry out actions likely to cause or promote the introduction or spread of invasive

species in the United States or elsewhere, unless the USACE has determined and

made public its determination that the benefits of such actions clearly outweigh the

potential harm caused by invasive species, and that all feasible and prudent

measures to minimize risk of harm will be taken in conjunction with the actions.

The analysis of potential impacts of the NER Plan and the recommended component

of construction on invasive species is described in Section 5.6.5 -Invasive Species 

Vegetation.

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7.2.14 Executive Order 11988  Floodplain Management

Executive Order 11988 entitled Floodplain Management dated May 24, 1977,

requires Federal agencies to evaluate the potential effects of actions it may take in a

floodplain to avoid adversely impacting floodplains wherever possible, to ensure

that its planning programs and budget requests reflect consideration of flood

hazards and floodplain management, including the restoration and preservation of

such land areas as natural undeveloped floodplains, and to prescribe procedures to

implement the policies and procedures of this Executive Order. Guidance for

implementation of the Executive Order has been provided by the U.S. Water

Resources Council in its Floodplain Management Guidelines dated February 10,

1978 (see 40 FR 6030). The Floodplain / Wetland Public Notice and Statement of

Findings will be included in Appendix G.

7.2.15 Executive Order 11990  Protection of Wetlands

Executive Order 11990 entitled Protection of Wetlands, dated May 24, 1977,

requires Federal agencies to take action to avoid adversely impacting wetlands

wherever possible, to minimize wetlands destruction and to preserve the values of

wetlands, and to prescribe procedures to implement the policies and procedures of

this Executive Order. The analysis of potential impacts of the NER Plan and the

recommended component of construction on wetlands is described in Section 5.6.2.

7.2.16 Uniform Relocation Assistance and Real Property

Acquisition Policies Act of 1970

All real estate interests acquired for construction of the NER Plan and the

recommended component of construction will be in accordance with the provisions of

the Uniform Relocation Assistance and Real Property Acquisition Policies Act of

1970 (Uniform Act), as amended in 42 USC 4601-4655, and the Uniform

Regulations contained in 49 C.F.R. Part 24. The Uniform Act sets forth procedures

for the acquisition of private property for public use and specifically requires that

the acquiring agency appraise the real property interests it wishes to acquire and

provide the owner a written summary of the basis for the amount established as

just compensation.

7.2.17 Louisiana State Rare, Threatened, and Endangered

Species, and Natural Communities Coordination

On February 3, 1999, Executive Order 13112 was signed to prevent the introduction

of invasive species and provide for their control and to minimize the economic,

ecological, and human health impacts that invasive species cause by establishing

the National Invasive Species Council. The Executive Order requires that a Council

of Departments dealing with invasive species be created. Currently there are 10

departments and agencies on the Council of Departments.

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The NER Plan and the recommended component of construction is consistent with

Executive Order 13112 to the extent practicable and permitted by law and subject

to the availability of appropriations, and within Administration budgetary limits.

The NER Plan and the recommended component of construction will use relevant

programs and authorities to prevent the introduction of invasive species and not

authorize, fund, or carry out actions likely to cause or promote the introduction or

spread of invasive species in the United States or elsewhere unless the USACE has

determined and made public its determination that the benefits of such actions

clearly outweigh the potential harm caused by invasive species; and that all feasible

and prudent measures to minimize risk of harm will be taken in conjunction with

the actions. The analysis of potential impacts of the NER Plan and the

recommended component of construction on EFH is described in Section 5.11 -

Threatened and Endangered Species.

7.2.18 Coastal Barrier Resources Act of 1982

The Coastal Barrier Resources Act (CBRA) was passed in 1982 in an effort to

discourage development on certain barrier islands and thereby minimize (1) loss of

human life and property from storms, (2) wasteful Federal expenditures, and (3)

damage to fish, wildlife, and other natural resources. This act prohibits most new

Federal financial assistance such as national flood insurance for projects within the

designated Coastal Barrier Resources System. The CBRA designated various

undeveloped coastal barrier islands, which were illustrated by a set of maps

adopted by law, to be included in the John H. Chafee Coastal Barrier Resources

System (CBRS). According to boundary maps prepared by the USFWS, the Study

Area is included in the John H. Chafee Coastal Barrier Resources System.

Compliance with the CBRA will be coordinated with the USFWS who is the primary

authority for implementation of the CBRA.

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8.0 CONCLUSIONS AND DETERMINATIONS

8.1 AREAS OF CONTROVERSY AND UNRESOLVED ISSUES

An area of controversy that exists is the effectiveness of hardened structures, most

notably, rock breakwaters and revetments, in achieving the Study goals. As

previously described in the report, hard structures that have been used in the past

on East Timbalier Island and Raccoon Island have had mixed results. The

construction of jetties at Belle Pass and the seawall-groin systems along East

Timbalier have been linked to the present erosion problems on East Timbalier,

whereas, the segmented rock breakwaters on Raccoon have had positive results to

date.

A concurrent resolution, sponsored by Representative Gordon Dove of Terrebonne

Parish, was passed during the 2006 Regular Session of the Louisiana Legislature

which prompted the United States Congress to ensure that any USACE projects

designed to restore the barrier islands protecting Terrebonne and Timbalier Bays

utilize hardened material to redefine and narrow Whiskey Pass, Wine Island Pass,

and Cat Island pass. During the public scoping meeting held in March 2009,

Terrebonne Parish President Mr. Michel Claudet and other members of the public

stressed that rocks should be given proper consideration in light of the positive

benefits demonstrated at Raccoon Island.

The Louisiana Department of Wildlife and Fisheries (LDWF) have also been very

supportive of the use of hard structures on Raccoon and Whiskey Islands. Both of

these islands are owned and managed by LDWF.

The PDT evaluated the use of segmented breakwaters on Whiskey Island and

segmented breakwaters and a terminal groin on Raccoon Island using the

GENESIS Model. Model results indicated that the breakwaters reduced erosion on

Whiskey Island and Raccoon Island by 5.62 ft/year and 0.80 ft/year respectively.

However, further analysis revealed that barrier island restoration using dredged

material was a more cost-effective method of maximizing habitat created over the

50-year period of analysis.

The GENESIS model indicated that the terminal groin on Raccoon Island would

result in accretion of sand on the western end of Raccoon Island and would yield

cost-effective net benefits over 50-year period of analysis. The Raccoon Island

terminal groin has been included in the NER Plan.

Due to the highly variable nature of the coastal processes within the Terrebonne

Basin and the limitations of modeling barrier island restoration performance and

response to structures with the GENESIS model as noted in Appendix L, it is

recommended that combined wave and current modeling be conducted in PED on a

system-wide level to support the NER Plan.

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Because the neither the NER Plan nor recommended component of construction

stop the problems that cause coastal erosion, there is concern that the plans are not

sustainable. The island will begin to erode soon after construction, unable to

maintain a stable level of benefits. The plan keeps intact the geomorphic and

hydrologic structure and function of a barrier island throughout the period of

analysis, providing benefits, albeit on a declining scale. The diminishing benefits

are accounted for in the WVA benefits analysis.

The impacts of the Deepwater Horizon oil spill on coastal Louisiana are uncertain

at this time (October 2010). The impacts of the oil spill as well as the various

emergency actions taken to address oil spill impacts (e.g., use of oil dispersants,

creation of sand berms, use of Hesco baskets, rip-rap, sheet piling and other actions)

could potentially impact USACE water resources projects and studies within the

Louisiana coastal area, including the LCA TBBSR Study. Potential impacts could

include factors such as changes to existing, Future Without, and Future With

Project conditions, as well as increased project costs and implementation delays.

The USACE will continue to monitor and closely coordinate with other Federal and

State resource agencies and local sponsors in determining how to best address any

potential problems associated with the oil spill that may adversely impact project

implementation. Supplemental planning and environmental documentation may be

required as information becomes available. If at any time petroleum or crude oil is

discovered on project lands, all efforts will be taken to seek clean up by the

responsible parties, pursuant to the Oil Pollution Act of 1990 (33 U.S.C. 2701 et

seq.).

Ongoing documentation of the impacts associated with the Deepwater Horizon Oil

spill can be found in several governmental sources. The USFWS Situation Report

for August 2, 21010 (http://www.fws.gov/home/dhoilspill/pdfs/MondayAugust22010.pdf)

indicates the following environmental-related Deepwater Horizon oil spill

information: 563 personnel are actively engaged in the response, working to protect

wildlife and their habitats, including 36 national wildlife refuges. They are also

assessing the damage from the oil spill in preparation for the work that will be

needed to restore the Gulf of Mexico. Some 1,643 visibly oiled birds have been

collected alive by the USFWS and our partners in response to the Deepwater

Horizon oil spill. Of those, 594 birds have been rehabilitated and released. Another

1,451 visibly oiled birds have been collected dead. Aerial operations over Louisiana

observed an oil sheen covering 300 acres in the northeastern portion of Barataria

Bay. A heavily oiled coastline covering about one-half mile was found at Bayou

Chalond and heavy oil and tar balls were observed on landfall east of Point-Au-Fer

and along Timbalier Island. Beached bird surveys were conducted in Texas,

Louisiana, Mississippi, Alabama and Florida. Aerial missions are scheduled for

Southwest Pass, Chandeleur Islands, Biloxi Marsh, Barataria Bay, Terrebonne,

Marsh Islands, Atchafalaya Delta, Point-Au-Fer and Timbalier Bay.

 Overall number of personnel responding: approximately 30,100

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 Total vessels responding: more than 4,500

 Total boom deployed: more than 2,155 miles

 Boom available: more than 856 miles

 Oily water recovered: more than 34.7 million gallons

 Estimated 11.14 million gallons of oil burned

 Estimated total of more than 1.84 million gallons of dispersant used

including:

o Estimated more than 1.07 million gallons surface dispersant used

o Estimated more than 771,000 gallons of sub-sea dispersant used:

 Estimated approximately 632 miles of Gulf Coast shoreline is currently

oiledapproximately 365 miles in Louisiana, 111 miles in Mississippi, 68

miles in Alabama, and 88 miles in Florida.

The USACE, New Orleans District Regulatory Branch has considered and

responded to approximately 55 emergency permits related to the Deepwater

Horizon oil spill (http://www.mvn.usace.army.mil/pao/mvnoilspill.asp). Of particular

concern are the permitted activities proposed for the islands in the LCA TBBSR

Study (Table 8-1).

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Table 8-1. USACE New Orleans District Regulatory Branch Deepwater Horizon Emergency PermitRequest

DA Number Project Name Applicant Action Date Received Date Issued Date Denied Date Withdraw

n

MVN-2010-01136-WJ

Deepwater Horizon Oil Spill- State ofLouisiana- Create Sand Protection BermIsles Dernieres Chain, Terrebonne Ph. La. OCPR NOD-20 18-May-10 6-Jul-10

MVN-2010-01151-WB

Deepwater Horizon Oil Spill - TerrebonneParish Government, Trinity Island, sandbags

TerrebonnePh Govt NOD-20 24-May-10 4-Jun-10

MVN-2010-01267-WB

Deepwater Horizon Oil Spill - TerrebonneParish Government, install sheetpile withtiebacks for Closure of Canal 19 onTimbalier Island

TerrebonnePh Govt NOD-20 4-Jun-10 4-Jun-10

MVN-2010-01338-WJJ

Deepwater Horizon Oil Spill, TerrebonneParish, Dredge and Place Fill to CreateEmbankment

TerrebonnePh Govt NOD-20 11-Jun-10 15-Jun-10

MVN-2010-01473-WB

Deepwater Horizon Oil Spill - BP -Emergency Authorization for Piling/BoomInstallation at Raccourci Lake - Lafourche

BP AmericaProduction Co NOD-20 22-Jun-10 24-Jun-10

MVN-2010-01549-WJJ

Deepwater Horizon Oil Spill - EmergencyAuthorization to Fill Breaks along TwinPipeline Canal Levee - Terrebonne,Lafourche

TerrebonnePh Levee andConservationDistrict

NOD-20 29-Jun-10 7-Jul-10

MVN-2010-01554-WB

Deepwater Horizon Oil Spill - EmergencyAuthorization for Pilings and Booms atWine Island & Raccoon Island inTerrebonne Parishes

La. Wildlife &Fisheries NOD-20 30-Jun-10 1-Jul-10

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In addition, the State of Louisiana is permitted to dredge and fill to construct six

sand berm reaches along the shoreline of the Chandeleur Islands/Breton National

Wildlife Refuge westward to Baptiste Collette Bayou and along the seaward

shoreline of Timbalier Island eastward to Sandy Pont. Material to construct the

berms would be dredged from Ship Shoal, South Pelto, the Mississippi River

Offshore Disposal Site, Pass a Loutre, St. Bernard Shoal and Hewes Point.

Emergency permits have the following clause that provides for removing, relocating,

or altering permitted structures if necessary and upon due notice from the Corps.

The clause would pertain to future actions by the United States, such as proposed

Louisiana Coastal Area restoration projects:

The permittee understands and agrees that, if future operations by the United

States require the removal, relocation, or other alteration, of the structure or

work herein authorized, or if, in the opinion of the Secretary of the Army or his

authorized representative, said structure or work shall cause unreasonable

obstruction to the free navigation of the navigable waters, the permittee shall

be required upon due notice from the Corps of Engineers, to remove, relocate,

or alter the structural work or obstructions caused thereby, without expense to

the United States. No claim shall be made against the United States on

account of any such removal or alteration.

As is evident from the numerous ongoing actions, the dynamic nature of the impacts

associated with the Deepwater Horizon oil spill will likely require additional

consideration in the near future for USACE Civil Works projects.

8.2 CONCLUSIONS

Alternative 5 (Raccoon with Terminal Groin (Plan E) / Whiskey (Plan C) / Trinity

(Plan C) / and Timbalier (Plan E)) was selected as the NER Plan. The plan would

add 3,283 acres of habitat (dune, intertidal, and supratidal) to the existing island

footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing the total

size of the islands to 5,840 acres. This would result in the restoration and creation

of approximately 472 acres of dune, 4,320 acres of supratidal habitat, and 1,048

acres of intertidal habitat. Renourishment events will occur at TY 30 for Raccoon

Island Plan E and Timbalier Plan E, TY25 for Trinity Island Plan C, and TY20 and

TY40 for Whiskey Island Plan C.

The barrier island restoration features of the NER Plan would achieve the planning

objectives by maximizing the barrier islands ability to provide geomorphic and

hydrologic form and ecological function over the 50-year period of analysis as well

as improve critical barrier island habitats for fish, migratory birds, and other

terrestrial and aquatic species. Sediment would be placed into the system to

supplement longshore sediment transport processes along the gulf shoreline by

mechanically introducing compatible sediment, and increasing the ability of the

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restored area to continue to function and provide habitat with minimum continuing

intervention.

The NER Plan is the plan that best meets the goal of the 2004 LCA Plan to address

critical near-term needs for shoreline restoration for Terrebonne Basin through

simulating historical conditions by enlarging the barrier islands (width and dune

crest) and reducing the current number of breaches to ensure the continuing

geomorphic and ecological form and function of the barrier islands. The selection of

the NER Plan was based on a thorough review of existing scientific and engineering

reports, as well as geospatial, survey, and geotechnical data which reaffirmed that

the findings of the Final Programmatic Environmental Impact Statement remained

valid.

The NER Plan is also the plan that best meets the USACE Principles and

Guidelines of completeness, effectiveness, efficiency, and acceptability, as well as

the Environmental Operating Principles of environmental sustainability,

interdependence, balance and synergy, accountability, knowledge, respect, and

assessing and mitigating cumulative impacts.

However, the NER Plan cannot be constructed within WRDA 2007 authorization.

Therefore Whiskey Island Plan C, a subset of the NER Plan was selected as the

recommended component of construction. The plan will restore a total of 1,272 acres

on the island, including 65 acres of dune, 830 acres of supratidal habitat, and 377

acres of intertidal habitat. The plan will be constructed on the existing island

footprint, which consists of 377 acres of supratidal habitat and 443 acres of

intertidal habitat at TY0. A renourishment event will be conducted at TY20 and at

TY40 in order to maintain the geomorphic form and ecologic function of the island

throughout the 50-year period of analysis. Whiskey Island Plan C is an

implementable increment of the NER plan, meets the LCA Program and project

objectives, and is within the cost and scope of the WRDA authorization.

8.3 RECOMMENDATIONS

The District Commander has considered all the significant aspects of this study

including the environmental, social, and economic effects, engineering feasibility,

and the comments received from the non-Federal sponsors, the public, and other

resource agencies. Based on this information, the District Commander has

determined that the NER Plan presented in this report is in the overall public

interest and is a justified expenditure of Federal funds. Therefore, the District

Commander recommends the NER Plan for implementation.

Alternative 5 (Raccoon with Terminal Groin (Plan E) / Whiskey (Plan C) / Trinity

(Plan C) / and Timbalier (Plan E)) was selected as the NER Plan because it is a Best

Buy plan that fulfills the planning objectives in Section 2.3 of this report. The NER

Plan would restore the geomorphologic form and ecologic function of the four islands

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in the Terrebonne Basin barrier system. Immediately after construction (TY1), the

NER Plan would add 3,283 acres of habitat (dune, intertidal, and supratidal) to the

existing island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands,

increasing the total size of the islands to 5,840 acres. This would result in the

restoration and creation of approximately 472 acres of dune, 4,320 acres of

supratidal habitat, and 1,048 acres of intertidal habitat.

The creation of dune, supratidal, and intertidal habitats would provide essential

habitats for fish, migratory birds, and other terrestrial and aquatic species.

Furthermore, by using the proposed borrow areas, the NER Plan would increase

sediment input to supplement longshore sediment transport processes along the

gulf shoreline by mechanically introducing compatible sediment, and increasing the

ability of the restored area to continue to function and provide habitat with

minimum continuing intervention. Sediment placed on Trinity Island would

eventually be transported to Whiskey Island and Raccoon Island as the sediment

moves westward through the system. Raccoon Island would also receive sediment

directly from Whiskey.

The NER Plan includes renourishment at staggered intervals for each island over

the 50-year period of analysis. Renourishment events will occur at TY 30 for

Raccoon Island Plan E and Timbalier Plan E, TY25 for Trinity Island Plan C, and

TY20 and TY40 for Whiskey Island Plan C.

The NER Plan was also selected because it would protect existing critical habitat on

Raccoon and Whiskey Islands. Raccoon Plan E and Whiskey Plan C were designed

to avoid approximately 58 and 286 acres of existing mangroves on the islands,

respectively, thereby minimizing potential adverse ecologic impacts during

construction. Since these two islands are considered to be valuable wildlife habitats

(Isles Dernieres Barrier Islands Wildlife Refuge) and the LDWF is reestablishing a

pelican rookery on Whiskey Island, maintaining adequate areas of healthy beach,

dune, and marsh is particularly important. Raccoon, Whiskey, Trinity, and

Timbalier are also a critical habitat for endangered species including the piping

plover and are a valuable stopover habitat for migratory birds.

In addition to protecting and maintaining ecological benefits, the NER Plan would

supplement existing State investments on the island. For example, Whiskey Plan C

was designed to complement TE-50, which is an existing CWPPRA project that was

constructed in 2009. Raccoon Plan E was designed to complement two separate

CWPPRA projects, TE-29 and TE-48.

The NER Plan meets the LCA program and project objectives and is within the

scope of the authorization. However, it exceeds the authorized cost. The State of

Louisiana, acting as the non-Federal sponsor, concurs with the District

Commanders recommendation that additional Congressional authorization be

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requested to allow implementation of the NER plan to fully address the restoration

needs of the Study Area identified in this report. The estimated total first cost of

the NER plan is $646,931,000. The Federal share of the estimated first cost of this

project is $420,505,000 and the non-Federal share is $226,426,000.

The District Commander recommends that the recommended component of

construction (Whiskey Island Plan C) of the NER plan be implemented under the

existing authority provided in Section 7006(e)(3) of WRDA 2007. Whiskey Island

Plan C includes renourishment at TY20 and TY40 to maintain the constructed

features. Restoration of the one island will increase habitat function by 678

AAHUs by restoring a total of 1,272 acres on the island, including 65 acres of dune,

830 acres of supratidal habitat, and 377 acres of intertidal habitat. Whiskey Island

Plan C is an implementable increment of the NER plan, meets the LCA Program

and project objectives, and is within the cost and scope of the WRDA authorization.

The State of Louisiana, acting as the non-Federal sponsor, supports immediate

implementation of Whiskey Island Plan C as the recommended component of

construction. The estimated total first cost of the Whiskey Island Plan C is

$113,434,000. The Federal share of the estimated first cost of this project is

$73,732,000 and the non-Federal share is $39,702,000. Implementation

requirements and responsibilities are discussed in Section 3.10.2.

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9.0 DISTRIBUTION LIST AND OTHER

9.1 DISTRIBUTION LIST

This Integrated Feasibility Report and Final EIS will be distributed to Federal,

State, parish, and local agencies; tribes; businesses; libraries; museums;

universities; environmental organizations, groups and individuals; and scoping

participants. The complete distribution list will be available upon request from the

USACE at the following address.

U.S. Army Corps of Engineers

New Orleans District

P.O. Box 60267

New Orleans, Louisiana 70160-0267

9.2 LIST OF PREPARERS

Many individuals were involved with the completion of this document. The

following table lists those people who assisted in writing this Integrated Feasibility

Study and Final EIS.

Table 9-1: List of preparers

Name Job Title / Discipline

US Army Corps of Engineers, New Orleans District

Darrel Broussard Senior Project Manager

Paul Varnado Project Manager

Axtman, Tim Senior Plan Formulator

Lachney, Fay Plan Formulator

Boyce, Mayely Counsel

Britsch, Louis Geologist

Brown, Christopher HTRW

Burks, Fred Project Management

Clark, Erin Real Estate

Crawford, Mathew Engineering team lead

Dehaan, Andre Geospatial Engineering

Deloach, Pam Engineering and Design

Demarcay, Gary Archeologist

Fernandez, Bill Scheduler

Gautreau, Paul Engineering Surveys

Haab, Mark Economics

Hill, Rebecca Archeologist

Klein, William Environmental Management

Ayres, Steve H&H

Leaumont, Brian Engineering - Civil

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Name Job Title / Discipline

Mann, Joe Economics

McCaffrey, Kelly Aesthetics

Moore, Kiandra Program Analyst

O'Cain, Keith Engineering

Perez, Andrew Recreation

Petitbon, John Cost Engineering

Ramos, Miguel Cost Engineering

Serrano, Josinell Engineering

Smith, Sylvia Engineering

Talbert, Christopher Engineering - Relocations

Woodward, Mark Geotechnical Engineering

Louisiana Office of Coastal Protection and Restoration

Bass, Aaron SJB Senior Project Manager

Beall, Andrew OCPR Project Manager

Breland, Clayton OCPR Geologist

Cangelosi, Robert SJB Site Development Manager

Carloss, Mike WLF

Dartez, Steve CEC Field Engineer

Dean, Christopher SJB Project Manager

Dearmond, Daniel OCPR Operations Engineer

Finley, Heather WLF

Green, Mandy OCPR Environmental Manager

Khalil, Syed OCPR LACES

LeBlanc, Paul SJB Environmental Scientist

LeBlanc, Wes OCPR Study Manager

Martin, Summer OCPR Environmental Scientist

Montgomery, Joyce OCPR Landrights Manager

Poff, Michael CEC Project Manager

Rabalais, Ronnie SJB Real Estate Services Division Manager

Rodrigue, Laurie OCPR Project Scientist

Simoneaux, Rudy OCPR Project Engineer

Staiger, Jon CEC Senior Scientist

Stephen, Michael CEC Project Manager

Suir, Glenn SJB GIS Specialist

Thoemke, Kris CEC Ecologist

Zwerneman, Kevin CEC Staff Engineer

Government Agencies

Baumgart-Getz, Adam USGS

Boustany, Ron USDA

Broussard, Loland USDA

Ettinger, John EPA

Merritt, Stacie MMS

Soileau, Karen USFWS (Biologist)

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Name Job Title / Discipline

Wikel, Geoffrey MMS

Williams, Patrick NOAA

9.3 LITERATURE CITED

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Intergovernmental Panel on Climate Change (IPCC) 2007. Climate Change 2007:

The Physical Science Basis, Contribution of Working Group I to the Fourth

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Khalil, S., Finkl, C, Roberts, H., and Raynie, R., 2010. New Approaches to

Sediment Mangement on the Inner Continental Shelf Offshore Coastal Louisiana,

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Resources, Regional Geology, and Coastal Processes for the Restoration of the

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Orleans District, September 2001. US Geological Survey Open File Report 01-384.

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Processes, and Sand Resources in the Vicinity of East Timbalier Island. Report to

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Kulp, M., Pennland, S., Williams, SJ., Jenkins, C., Flocks, J., and Kindinger, J.

Geologic framework, evolution, and sediment resources for restoration of the

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Louisiana Department of Natural Resources. 2004. 2004 Operations, Maintenance,

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Ritchie, William, K. Westphal, R. A. McBride, S. Penland. 1989. Coastal Geology

Technical Report No. 5. Coastal Sand Dunes of Louisiana. The Isles Dernieres.

Louisiana Geological Survey, Department of Natural Resources. Baton Rouge,

Louisiana.

Ritchie W, Westphal KA, McBride RA, and Penland S. 1990. Coastal sand dunes of

Louisiana the Plaquemines shoreline. Louisiana Geological Survey. Coastal Geology

Technical Report. 90 pp.

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Ritchie, William, K. Westphal, R. A. McBride, S. Penland. 1995. Coastal Geology

Technical Report No. 9. Coastal Sand Dunes of Louisiana. Bayou Lafourche Barrier

Shoreline. Louisiana Geological Survey, Louisiana State University. Baton Rouge,

Louisiana.

Rounsefell, G.A. 1975. Ecology, utilization, and management of marine fisheries.

The C.V. Mosby Company, St. Louis, Missouri.

Saucier, M.H. and D.M. Baltz 1993. Spawning site selection by spotted seatrout,

Cynoscion nebulosus, and black drum, Pogonias cromis, in Louisiana. Environ. Biol.

Fish. 36:257-272.

SCORP. 2003. 2003-2008 Louisiana Statewide Comprehensive Outdoor Recreation

Plan. Louisiana Department of Culture, Recreation, and Tourism. Office of State

Parks, Division of Outdoor Recreation. Published by Louisiana State Library.

Showalter and Schiavinato. 2004. Marine Protected Areas in the Gulf of Mexico: A

Survey. Supported by the National Sea Grant College Program of the U.S.

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Shoreline Protection/Marsh Creation Project Phase B (TE-48), Offshore Geophysical

and Geotechnical Report.

Stone, G.W. and Zhang X. 2001. A Longshore Sediment Transport Model for the

Timbalier Islands, Louisiana. Baton Rouge, Louisiana: Coastal Studies Institute

Louisiana State University.

Stone, G.W., Pepper, D.A., Xu, J., and Zhang, X., 2004. Ship Shoal as a Prospective

Borrow Site for Barrier Island Restoration, Coastal South-Central Louisiana, USA:

Numerical Wave Modeling and Field Measurements of Hydrodynamics and

Sediment Transport. Journal of Coastal Research, 20(1), 70-89. West Palm Beach

(Florida), ISSN 0749-0208.

Stone, G.W., Zhang, X.P., and Sheremet, A. The role of barrier islands, muddy

shelf and reefs in mitigating the wave field along coastal Louisiana. Journal of

Coastal Research Sp.Iss. 44 (2005): 40-55.

Stone, G.W. et al. 2009. Environmental Investigation of the Long-Term Use of

Ship Shoal Sand Resources for Large Scale Beach and Coastal Restoration in

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Louisiana. U.S. dept. of the Interior, Minerals Management Service, Gulf of Mexico

OCS region, New Orleans, LA. OCS Study MMS 2009-024. 278 pp.

Suter, J.R., Berryhill, H.L., and Penland, S. Delineation of Late Quaternary

Depositional sequences by high-resolution seismic stratigraphy, Louisiana

Continental-Shelf. AAPG- American Assocation of Petroleum Geologists 71

(1987):620-620.

Suter, J. R., Penland, S., and Ramsey, K. E. 1991. Nearshore Sand Resources of the

Mississippi River Delta Plain: Marsh Island to Sandy Point. Coastal Geology

Technical Report No. 8. Louisiana Geological Survey.

T. Baker Smith. 1997. Evaluation and Recommendation of the Barrier Shoreline

Feasibility Study. Houma, La. September 1997.

T. Baker Smith and Moffatt & Nichol (TBS and M&N). 2007. Whiskey Island Back

Barrier Marsh Creation (TE-50) 95% Design Report, Appendix B, OSIs

Hydrographic, Geophysical, and Geotechnical Survey Program.

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April, 2004.

Thompson, B. 1988. Fish and Shellfish, 1988. Isles Dernieres Barrier Island

Stabilization project, State Project No. 750-55-01, Draft Environmental Assessment

submitted to State of Louisiana Department of Transportation and Development,

September 1988. Plaisance/Smith Engineers. Houma, Louisiana.

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The ecology of Barataria Basin, CA: an estuarine profile. U.S Fish Wildl. Serv. Biol.

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U.S. Army Corps of Engineers. 2004c. Louisiana Coastal Area (LCA) Ecosystem

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Louisiana for Coastal and barrier Island Nourishment and hurricane levee

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Archaeological Survey of Portions of Blocks 87, 88, 89, 94, and 95 Ship Shoal Area.

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Archaeological Survey of the South Pelto Area Block 13 Vicinity of Ship Shoal. New

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U.S. Fish and Wildlife Service. 1996. Piping Plover (Charadrius melodus), Atlantic

Coast Population, Revised Recovery Plan. Hadley, Massachusetts.

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dynamics of seabirds nesting in Louisiana. Colonial Waterbirds 17(2): pp. 146-152.

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Aquatic Habitats of East Timbalier Island, Louisiana. M.S. thesis, Louisiana State

University, Baton Rouge, Louisiana.

Zimmerman, R.J. 1988. A Survey and Assessment of Usage of a Salt Marsh at

Grand Isle, Louisiana by Estuarine Aquatic Fauna. Dallas, Texas. 14 pp.

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9.4 GLOSSARY

Acceptability Adequate to satisfy a need, requirement, or standard. One of

the USACE requirements for a project.

Adaptive

Management

An interdisciplinary approach acknowledging our

insufficient information base for decision-making; that

uncertainty and change in managed resources are

inevitable; and that new uncertainties will emerge. An

iterative approach that includes monitoring and involves

scientists, engineers and others who provide information

and recommendations that are incorporated into

management actions; results are then followed with further

research, recommendations and management actions, and

so on.

Air Quality

Determination

The Louisiana Department of Environmental Quality

ensures that projects do not adversely affect air quality

through this determination as a requirement of the Clean

Air Act.

Alternative Plan

A set of one of more management measures within a

subprovince functioning together to address one or more

objectives.

Amplitude The maximum absolute value of a periodically varying

quantity.

Anadromous Ascending rivers from the sea for breeding

Anoxia Absence of oxygen.

Anthropogenic Caused by human activity.

Average Annual

Habitat Unit (AAHU)

Represent a numerical combination of habitat quality and

quantity (acres) existing at any given point in time. The

habitat unites resulting from the future without- and future

with-project scenarios are annualized, averaged over the

project life, to determine Average Annual Habitat Units

(AAHUs).

Benefits Valuation of positive performance measures.

Benthic Living on or in sea, lake, or stream bottoms.

Biomass The total mass of living matter (plant and animal) within a

given unit of environmental area.

Bottomland

Hardwood Forest

Low-lying forested wetlands found along streams and rivers.

Brackish Marsh

(BRM)

Intertidal plant community typically found in the area of

the estuary where salinity ranges between 4-15 ppt.

Clean Water Act

Section 404 (b) (1)

There are several sections of this Act which pertain to

regulating impacts to wetlands. The discharge of dredged or

fill material into waters of the United States is subject to

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permitting specified under Title IV (Permits and Licenses)

of this Act and specifically under Section 404 (Discharges of

Dredge or Fill Material) of the Act.

Coastal Zone

Consistency

Determination

The U.S. Environmental Protection Agency reviews plans

for activities in the coastal zone to ensure they are

consistent with Federally approved State Coastal

Management Programs under Section 307(c)(3)(B) of the

Coastal Zone Management Act.

Coast wide Plan

Combination of alternative plans assembled to address an

objective or set of objectives across the entire Louisiana

Coast.

Collocated Team

A collection of scientists and professionals from the U.S.

Army Corps of Engineers, U.S. Fish and Wildlife Service,

NOAA Fisheries, Natural Resources Conservation Service,

U.S. Geological Survey, U.S. Environmental Protection

Agency, Louisiana Department of Natural Resources, and

Louisiana Department of Wildlife and Fisheries that are

located at the CEMVN office and work together on the LCA

Plan.

Comprehensive Plan Same as coast wide Plan.

Conditional

Authorization

Authorization for implementation of a project subject to

approval of the project feasibility-level decision document by

the Assistant Secretary of the Army for Civil Works

Congressional

Authorization

Authorization for investigation to prepare necessary

feasibility-level report to be recommended for authorization

of potential future project construction by Congress

Connectivity Property of ecosystems that allows for exchange of resources

and organisms throughout the broader ecosystem.

Continental Shelf The edge of the continent under gulf waters; the shallow

Gulf of Mexico fringing the coast.

Control Structure A gate, lock, or weir that controls the flow of water.

Cumulative Impacts The combined effect of all direct and indirect impacts to a

resource over time.

Datum A point, line, or surface used as a reference, as in surveying,

mapping, or geology.

Decomposition Breakdown or decay of organic materials.

Degradation Phase

The phase of the deltaic cycle when sediments are no longer

delivered to a delta, and it experiences erosion, dieback, or

breakup of marshes.

Deltaic Cycle

The repeating pattern of delta development, progression,

and abandonment. As sediments are deposited at the

mouth of the distributary channels, the delta progresses

seaward. The main channel then switches to a new course

with a shorter reach to the depositional basin. Abandoned

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delta lobes decrease in elevation due to continued

subsidence and sediment compaction, resulting in retreat of

the shoreline. Abandoned lobes may be partially or wholly

covered by new lobes during later deltaic cycles.

Deltaic Deposits Mud and sand deposited at the mouth of a river.

Deltaic Plain

The land formed and reworked as the Mississippi River

switched channels in the eastern part of the Louisiana

coastal area.

Detritus The remains of plant material that has been destroyed or

broken up.

Dewatering The process of dredged sediments compacting while losing

water after being deposited.

Discharge

The volume of fluid passing a point per unit of time,

commonly expressed in cubic ft per second, millions of

gallons per day, or gallons per minute.

Dissolved Oxygen

Oxygen dissolved in water, available for respiration by

aquatic organisms. One of the most important indicators of

the condition of a water body.

Direct Impacts

Those effects that result from the initial construction of a

measure (e.g., marsh destroyed during the dredging of a

canal). Contrast with Indirect Impacts.

Diurnal Relating to or occurring in a 24-hour period; daily.

Diversion

A turning aside or alteration of the natural course or flow of

water. In coastal restoration this usually consists of such

actions as channeling water through a canal, pipe, or

conduit to introduce water and water-borne resources into a

receiving area.

Dredged material

embankments (Spoil

Banks, Side-cast

Banks, Excavated

Material Banks)

Dredged material removed from canals and piled in a linear

mound along the edge of canals.

Dynamic Characterized by continuous change and activity.

Ecological Refers to the relationship between living things and their

environment.

Economic

Of or relating to the production, development, and

management of material wealth, as of a country, household,

or business enterprise.

Ecosystem

An organic community of plants and animals viewed within

its physical environment (habitat); the ecosystem results

from the interaction between soil, climate, vegetation, and

animal life.

Ecosystem

Restoration

Activities that seek to return a organic community of plants

and animals and their habitat to a previously existing or

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improved natural condition or function.

Effectiveness

Having an intended or expected effect. One of the USACE

four requirements for

a project.

Efficiency The quality of exhibiting a high ratio of output to input.

One of the USACE four requirements for a project.

Egress A path or opening for going out; an exit.

Embankment A linear mound of earth or stone existing or built to hold

back water or to support a roadway.

Encroachment

Entering gradually into an area not previously occupied,

such as a plant species distribution changing in response to

environmental factors such as salinity.

Endangered Species Animals and plants that are threatened with extinction.

Enhance To augment or increase/heighten the existing state of an

area.

Environmental

Impact Statement

(EIS)

A document that describes the positive and negative

environmental effects of a proposed action and the possible

alternatives to that action. The EIS is used by the Federal

government and addresses social issues as well as

environmental ones.

Estuary A semi-enclosed body of water with freshwater input and a

connection to the sea where fresh water and salt water mix.

Estuarine Related to an estuary.

Evaporation

The process by which any substance is converted from a

liquid state into, and carried off in, vapor; as, the

evaporation of water.

Exotic Species

Animal and plant species not native to the area; usually

undesirable (e.g., hyacinth, nutria, tallow tree, giant

salvinia).

Feasibility Report

A description of a proposed action, previously outlined in a

general fashion in a Reconnaissance Report, that will satisfy

the Federal interest and address the problems and needs

identified for an area. It must include an assessment of

impacts to the environment (either in an Environmental

Assessment, or the more robust Environmental Impact

Statement), an analysis of alternative methods of

completion, and the selection of a Recommended Plan

through the use of a cost-effectiveness analysis.

Feature A constructible increment of an alternative plan.

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Federal Principals

Group (FPG)

A collaboration among Federal agencies at the Washington

level to facilitate the flow of information, to provide

guidance and recommendations to the USACE and LDNR

throughout the study process, and to facilitate resolution of

any interagency issues that may be identified in the conduct

of the study.

Final Array The final grouping of the most effective coast wide plans

from which a final recommendation can be made.

Foreshore Dikes

An embankment of earth and rock built to prevent floods or

erosion that is built in the area of a shore that lies between

the average high tide mark and the average low tide mark.

Framework

Development Team

(FDT)

A group of professionals from various Federal and state

agencies, academia and the public formed to provide a

forum for individual members to discuss LCA

Comprehensive Study activities and technical issues and to

provide individual comments to the Senior Management

Committee.

Fresh Marsh Intertidal herbaceous plant community typically found in

that area of the estuary with salinity ranging from 0-3 ppt.

Furbearer

An animal whose skin is covered with fur (mammal),

especially fur that is commercially valuable, such as

muskrat, nutria, and mink.

Geomorphic Related to the geological surface configuration.

Goals Statements on what to accomplish and/or what is needed to

address a problem without specific detail.

Gradient A slope; a series of progressively increasing or decreasing

differences in a system or organism.

Habitat The place where an organism lives; part of physical

environment in which a plant or animal lives.

Habitat Loss

The disappearance of places where target groups of

organisms live. In coastal restoration, usually refers to the

conversion of marsh or swamp to open water.

Habitat Units (HUs)

Represent a numerical combination of quality (HSI) and

quantity (acres) existing at any given point in time. The

HUs resulting from the future without- and future withproject scenarios are annualized, averaged over the project

life, to determine Average Annual Habitat Units (AAHUs).

The benefit of a project can be quantified by comparing

AAHUs between the future without- and future with-project

scenarios. The difference in AAHUs between the two

scenarios represents the net benefit attributable to the

project in terms of habitat quantity and quality.

Hazardous, Toxic,

and Radioactive

Wastes that contain toxic constituents, or that may cause

hazardous chemical reactions, including explosive or

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Wastes (HTRW) flammable materials, or radioactive wastes, which,

improperly managed may present a hazard to human heath

or

the environment.

Headland A point of land projecting into the sea or other expanse of

water, still connected with the mainland.

Herbaceous A plant with no persistent woody stem above ground.

Hydrodynamic The continuous change or movement of water

Hydrology The pattern of water movement on the earth's surface, in

the soil and underlying rocks, and in the atmosphere.

Hypoxia The condition of low dissolved oxygen concentrations.

Indemnification Insurance against or compensation for loss or damage.

Indirect Impacts

Those effects that are not as a direct result of project

construction, but occur as secondary impacts due to changes

in the environment brought about by the construction.

Contrast with Direct Impacts.

Infrastructure

The basic facilities, services, and installations needed for

the functioning of a community or society, such as

transportation and communications systems, water and

power lines, and public institutions including schools, post

offices,

and prisons.

Ingress An entrance or the act of entering.

Inorganic Not derived from living organisms; mineral; matter other

than plant or animal.

Interdistributary

Deposits

Sand and mud deposited between the river channels or

between bayous.

Intermediate Marsh Intertidal herbaceous plant community typically found in

that area of the estuary with salinity ranging from 2-5 ppt.

Intertidal Alternately flooded and exposed by tides.

Invertebrates Animals without backbones, including shrimp, crabs,

oysters, and worms.

Larvae The stage in some animals life cycles between egg and adult

(most invertebrates).

Leeward Sheltered from the wind; away from the wind.

Levee

A linear mound of earth or stone built to prevent a river

from overflowing; a long, broad, low ridge built by a stream

on its flood plain along one or both banks of its channel in

time of flood.

Locally Preferred

Plan (LPP)

Alternative plan preferred by local sponsor if other than the

Recommended Plan.

Maintain To keep in existing state.

Methodology A set of practices, procedures, and rules.

Mineral Substrate Soil composed predominately of mineral rather than organic

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materials; less than 20% organic material.

Mudflats Flat, unvegetated wetlands subject to periodic flooding and

minor wave action.

National Ecosystem

Restoration (NER)

USACE standard for cost-effectiveness based on ecosystem,

not

economic, benefits.

Near-shore Currents

Movement of water parallel to the shoreline. Usually

generated by waves breaking on the shore at an angle other

than perpendicular.

National

Environmental

Policy Act (NEPA)

Ensures that Federal agencies consider the environmental

impacts of their actions and decisions. NEPA requires all

Federal agencies to consider the values of environmental

preservation for all significant actions and prescribes

procedural measures to ensure that those values are fully

respected.

Net Gain The amount of cumulative land gain less land loss, when

gain is greater than loss.

Net Loss The amount of cumulative land gain less land loss, when

gain is less than loss.

No Action

Alternative

The alternative in the EIS which describes the ecosystem of

the coastal area if no restoration efforts/projects were done.

Nursery A place for larval or juvenile animals to live, eat, and grow.

Objectives

More specific statements than Goals, describing how to

achieve the

desired targets.

Organic Composed of or derived from living things.

Oscillations Fluctuations back and forth, or up and down.

Oxidation of Organic

Matter

The decomposition (rotting, breaking down) of plant

material through exposure

to oxygen.

Oxygen-depleted Situation of low oxygen concentrations where living

organisms are stressed.

Planning Scale

Planning term that reflects the degree to which

environmental processes would be restored or reestablished,

and the resulting ecosystem and landscape changes that

would be expected over the next 50 years. This uppermost

scale is referred to as Increase. No net loss of ecosystem

function is Maintain. Reducing the projected rate of loss

of function is Reduce. The lowest possible scale was no

further action above and beyond existing projects and

programs.

Post-larval Stage in an animals lifecycle after metamorphosis from the

larval stage, but not yet full grown.

Potable Water Water that is fit to drink.

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ppt Parts per thousand. The salinity of ocean water is

approximately 35 ppt.

Prime Farmland

Land that has the best combination of physical and chemical

characteristics for producing food, feed, fiber, forage, oilseed,

and other agricultural crops with minimum inputs of fuel,

fertilizer, pesticides, and labor, and without intolerable soil

erosion. One of the categories of concern in the EIS.

Principles

Framing statements that can be used to evaluate

alternatives while considering issues that affect them. Used

along with targets and assessments of ecosystem needs to

provide guidance in formulation of alternative plans.

Productivity Growth of plants and animals.

Progradation

The phase during the deltaic cycle where land is being

actively accreted through deposition of river sediments near

the mouth.

Programmatic

Environmental

Impact Statement

(PEIS)

And Environmental Impact Statement that supports a

broad authorization for action, contingent on more specific

detailing of impacts from specific measures.

Province

A major division of the coastal area of Louisiana. (e.g.,

Deltaic Plain and

Chenier Plain).

Pulsing

Letting a diversion flow periodically at a high rate for a

short time, rather

than continuously.

Quantitative Able to assign a specific number; susceptible to

measurement.

Rebuild To some extent build back a structure/landform that had

once existed.

Reconnaissance

Report

A document prepared as part of a major authorization that

examines a problem or need and determines if sufficient

methods and Federal interest exists to address the

problem/need. If so, then a Feasibility Report is prepared,

which details the solution and its impacts further.

Reduce To diminish the rate or speed of a process.

Regional Working

Group (RWG)

An inter-agency team formed to support the Washingtonlevel Federal Principals Group and to facilitate regional

level collaboration and coordination on the

LCA study.

Rehabilitate

To focus on historical or pre-existing ecosystems as models

or references while emphasizing the reparation of ecosystem

processes, productivity and service.

Relative Sea Level

Change

The sum of the sinking of the land (subsidence) and eustatic

sea level change; the change in average water level with

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respect to the surface.

Restore

Return a wetland to an approximation of its condition or

function prior to disturbance by modifying conditions

responsible for the loss or change; re-establish the function

and structure of that ecosystem.

Saline Marsh

Intertidal herbaceous plant community typically found in

that area of the estuary with salinity ranging from 12-32

ppt.

Salinity The concentration of dissolved salts in a body of water,

commonly expressed as parts per thousand.

Salt Marshes See Saline Marsh.

Scoping

Soliciting and receiving public input to determine issues,

resources, impacts, and alternatives to be addressed in the

draft EIS.

Sea level Long-term average position of the sea surface.

Sediment Plume

Caused by sediment rich rainwater runoff entering the

ocean. The runoff creates a visible pattern of brown water

that is rich in nutrients and suspended sediments that

forms a kind of cloud in the water spreading out from the

coastline. Commonly forms at river and stream mouths,

near sloughs, and along coasts where a large amount of rain

runoff flows directly into the ocean.

Sheet Flow Flow of water, sediment, and nutrients across a flooded

wetland surface, as opposed to through channels.

Shoaling The shallowing of an open-water area through deposition of

sediments.

Social Relating to human society and its modes of organization.

Socioeconomic Involving both social and economic factors.

Stabilize To fix the level or fluctuation of; to make stable.

State Historic

Preservation Office

(SHPO)

The part of the Louisiana Department of Culture,

Recreation, and Tourism that deals with Native American

sites and other archaeological/historic sites.

Stillstand A period of time when sea level did not change.

Storm Overwash The process by which sand is transposed landward over the

dunes during a storm event by waves

Storm Surge

An abnormal and sudden rise of the sea along a shore as a

result of the winds of

a storm.

Strategy Ecosystem restoration concept from the Coast 2050 Plan.

Stream Gaging Data Records of water levels in streams and rivers.

Submergence Going under water.

Subprovince

The divisions of the two Provinces (see Province) into

smaller groupings:

1) east of the Mississippi River; 2) west of the Mississippi

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River to Bayou Lafourche; 3) Bayou Lafourche to

Freshwater Bayou; 4) Freshwater Bayou to Sabine River.

Subsidence The gradual downward settling or sinking of the Earths

surface with little or no horizontal motion.

Sustain To support and provide with nourishment to keep in

existence; maintain.

Target A desired ecosystem state that meets and objective or set of

objectives.

Terrestrial Habitat The land area or environment where an organism lives; as

distinct from water or air habitats.

Toxicity The measure of how poisonous something is.

Transpiration The process by which water passes through living plants

into the atmosphere.

Turbidity The level of suspended sediments in water; opposite of

clarity or clearness.

Upland A general term for non-wetland elevated land above low

areas along streams or between hills.

Water Resource

Units (WRU)

Stage-damage data developed as part of the Flood Damage

Estimation System (FDES) in 1980 for the Mississippi River

and Tributaries (MR&T) project were used to estimate the

flood damages that are expected to occur in Subprovinces 1,

2, and 3. The data collected for the FDES were delineated

into geographic areas with homogenous physical and

hydraulic characteristics. These geographic areas were

numerically coded and designated as Water Resource Units

(WRUs). Within each WRU, land-use elements (structures,

cropland, roads, bridges, railroads, etc.) were categorized by

location, value, and corresponding depth-damage

relationship. The structural damage categories included:

residential, commercial, industrial, public, and farm

buildings.

Water Resources

Development Act

(WRDA

A bill passed by Congress that provides authorization and/or

appropriation for projects related to the conservation and

development of water and

related resources.

Weir A dam placed across a canal or river to raise, divert,

regulate or measure the flow of water.

9.5 ACRONYMS, ABBREVIATIONS, SYMBOLS, AND INITIALISMS

AAHU Average Annual Habitat Unit

ACHP Advisory Council on Historic Preservation

BFE Base Flood Elevations

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BICM Barrier Island Comprehensive Monitoring Program

BMA benthic micro-algae

BMP Best Management Practices

BRM Brackish Marsh

BTNEP Barataria-Terrebonne National Estuary Program

CEMVN United States Army Corps of Engineers  Mississippi Valley

Division, New Orleans District

CE/ICA Cost Effectiveness and Incremental Cost Analysis

CEQ Council of Environmental Quality

CERCLA Comprehensive Environmental Response, Compensation, and

Liability Act

CFR Code of Federal Regulations

CIAP Coastal Impact Assistance Program

CoP Communities of Practice

CPRA Coastal Protection and Restoration Authority

CWA Clean Water Act

CWPPRA Coastal Wetland Planning, Protection Restoration Act

DEQ Department of Environmental Quality

DO Dissolved Oxygen

EA Environmental Assessment

ECO-PCX Ecosystem Center of Expertise

EIS Environmental Impact Statement

EOP Environmental Operating Principles

ER Engineering Regulation

ESLR Eustatic Sea Level Rise

E&T Endangered and Threatened Species

FDES Flood Damage Estimation System

FEIS Final Environmental Impact Statement

FEMA Federal Emergency Management Agency

FWOP Future Without Project

FWP Future With Project

FY Fiscal Year

GAP Gap Analysis Program

GIWW Gulf Intracoastal Waterway

GIS Geographic Information System

GOM Gulf of Mexico

GOMESA Gulf of Mexico Energy Security Act

HEP Habitat Evaluation Procedures

HNC Houma Navigation Canal

HQU Habitat Quality Units

HSI Habitat Suitability Index

HTRW Hazardous, Toxic, or Radioactive Waste

IBA Important Bird Areas

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IPCC Intergovernmental Panel on Climate Change

IWR Institute for Water Resources

LA Louisiana

LACES Louisiana Applied Coastal Engineering & Science

LCA Louisiana Coastal Area

LDNR Louisiana Department of Natural Resources

LDWF Louisiana Department of Wildlife and Fisheries

LERRD Land, Easements, Rights of Way, Relocation, and Disposal

LGS Louisiana Geological Survey

LiDAR Light Detection and Ranging

LL&E Louisiana Land and Exploration

LOOP Louisiana Offshore Oil Port

LSU Louisiana State University

MCACES Microcomputer Aided Cost Estimating System

MHW Mean High Water

MMS Minerals Management Service

MOU Memorandum of Understanding

MSL Mean Sea Level

MVD Mississippi Valley Division

NAVD 88 North American Vertical Datum of 1988

NED National Economic Development

NEPA National Environmental Policy Act

NER National Ecosystem Restoration

NGVD 29 National Geodetic Vertical Datum of 1929

NHPA National Historic Preservation Act

NMFS Department of Commerce  National Marine Fisheries Service

NOAA National Oceanic and Atmospheric Administration

NPDES National Pollutant Discharge Elimination System

NRC National Research Council

NRCS Department of Agriculture  Natural Resources Conservation

Service

OCPR Office of Coastal Protection and Restoration

OCS Outer Continental Shelf

OMRR&R Operating, Maintaining, Repairing, Replacing, and Rehabilitating

OSI Overall Suitability Index

O&M Operations and Maintenance

OPEC Organization of Petroleum Exporting Countries

P&G Principles & Guidelines

PDT Project Delivery Team

PED Preconstruction, Engineering, and Design

PIS Project Information Sheet

PPL Priority Projects List

REP Real Estate Plan

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ROD Record of Decision

RSLR Relative Sea Level Rise

SEIS Supplemental Environmental Impact Statement

SHPO State Historic Preservation Officer

SL Sediment Load

TEC Theater Engineer Commands

TPCZM Terrebonne Parish Coastal Zone Management

TY Target Year

USACE United States Army Corps of Engineers

USEPA United States Environmental Protection Agency

USFWS Department of Interior  U.S. Fish and Wildlife Service

USGS Department of Interior  United States Geological Survey

USDA United States Department of Agriculture

VE Value Engineering

WMA Wildlife Management Area

WRDA Water Resource Development Act

WVA Wetlands Value Assessment

YOD Year of Disappearance

685
MAIN REPORT

ATTACHMENT 1

Non-Federal Sponsor’s Letter of Intent

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Volume V  Terrebonne Basin Barrier Shoreline Restoration

Integrated Feasibility Study and Supplemental Environmental Impact Statement

For the

LCA Terrebonne Basin Barrier Shoreline Restoration

Terrebonne Parish, Louisiana

(APPENDICES A  M)

The responsible lead Federal agency for this study is the U. S. Army Engineer District, New Orleans. The

Non-Federal Sponsor for the study is the Louisiana Coastal Protection and Restoration Authority. The

responsible cooperating Federal agency is the U.S. Fish and Wildlife Service

U.S. Army Corps of Engineers (USACE) and the Council of Environmental Quality(CEQ), and is

intended to reduce duplication and paperwork. An asterisk (*) in the table of contents notes paragraphs

that are required for National Environmental Policy Act (NEPA) compliance.

. This report is a combined

feasibility report and environmental impact statement complying with requirements of the

October 2010

Coastal Protection and

Restoration Authority

U.S Army Corps of Engineers

New Orleans District



APPENDIX A

BIOLOGICAL ASSESSMENT



DRAFT

BIOLOGICAL ASSESSMENT

Louisiana Coastal Area (LCA)

Terrebonne Basin Barrier Shoreline Restoration

Terrebonne Parish, Louisiana

August 2010



i

TABLE OF CONTENTS

1 INTRODUCTION .................................................................................................................. 1

2 DESCRIPTION OF THE STUDY AREA ............................................................................. 1

2.1 Isles Dernieres Reach....................................................................................................................... 3

2.2 Timbalier Reach............................................................................................................................... 3

3 PURPOSE AND NEED FOR PROJECT............................................................................... 3

3.1 Critical Needs .................................................................................................................................. 4

3.2 Study Area Opportunities ................................................................................................................ 4

3.3 Planning Objectives ......................................................................................................................... 5

3.4 Planning Constraints........................................................................................................................ 5

3.5 Purpose............................................................................................................................................. 5

4 PROPOSED PROJECT .......................................................................................................... 6

4.1 National Ecosystem Restoration Plan.............................................................................................. 6

4.2 First Component of Construction..................................................................................................... 9

4.3 Components ..................................................................................................................................... 9

4.3.1 Raccoon Island Plan E with Terminal Groin .......................................................... 9

4.3.2 Whiskey Island Plan C.......................................................................................... 11

4.3.3 Trinity Island Plan C............................................................................................. 12

4.3.4 Timbalier Island Plan E ........................................................................................ 14

5 DESCRIPTION AND STATUS OF SPECIES .................................................................... 16

5.1 Piping Plover.................................................................................................................................. 19

5.2 West Indian Manatee ..................................................................................................................... 24

5.3 Hawksbill Sea Turtle...................................................................................................................... 24

5.4 Kemp’s Ridley Sea Turtle.............................................................................................................. 25

5.5 Leatherback Sea Turtle .................................................................................................................. 25

5.6 Green Sea Turtle ............................................................................................................................ 26

5.7 Loggerhead Sea Turtle................................................................................................................... 27

5.8 Brown Pelican................................................................................................................................ 28

5.9 Colonial Nesting Waterbirds.......................................................................................................... 29

6 ANTICIPATED EFFECTS OF THE PROPOSED PROJECT ............................................ 30

6.1 NER Plan ....................................................................................................................................... 30

6.1.1 Piping Plover......................................................................................................... 30


ii

6.1.2 West Indian Manatee ............................................................................................ 38

6.1.3 Sea Turtles ............................................................................................................ 39

6.1.4 Brown Pelican....................................................................................................... 40

6.1.5 Colonial Nesting Birds.......................................................................................... 41

6.2 First Component of Construction................................................................................................... 41

6.2.1 Piping Plover......................................................................................................... 41

6.2.2 West Indian Manatee ............................................................................................ 42

6.2.3 Sea Turtles ............................................................................................................ 42

6.2.4 Brown Pelican....................................................................................................... 43

6.2.5 Colonial Nesting Birds.......................................................................................... 43

6.2.6 Brown Pelican and Colonial Nesting Bird Protection Plan .................................. 44

7 REFERENCES ..................................................................................................................... 46


1

BIOLOGICAL ASSESSMENT

Louisiana Coastal Area (LCA)

Terrebonne Basin Barrier Shoreline Restoration

Terrebonne Parish, Louisiana

1 INTRODUCTION

Section 7(a)(2) of the Endangered Species Act (ESA) of 1973, as amended, requires that, “Each

Federal agency shall, in consultation with and with the assistance of the secretary, insure that any

action authorized, funded, or carried, out by such agency.... Is not likely to jeopardize the

continued existence of any endangered species or threatened species or result in the destruction

or adverse modification of habitat of such species...”

This Biological Assessment (BA) provides the information required pursuant to Implementing

Regulation 50 CFR 402.14 in accordance with the ESA. Additional jurisprudence includes the

National Environmental Policy Act (NEPA) of 1969, 42 U.S.C. section 4321, et seq.; the Fish

and Wildlife Conservation Act of 1958 (PL 85-624; 16 U.S.C. 661 et seq.); the Marine Mammal

Protection Act of 1972; and the Bald Eagle Protection Act of 1940. The purpose of the BA is to

evaluate the potential impacts of the proposed restoration efforts for the Terrebonne Basin

Barrier Shoreline Restoration (TBBSR) Study on Federally-listed and proposed threatened and

endangered species and designated and proposed critical habitat. Furthermore, the BA

determines whether any such species or habitats are likely to be adversely affected by

implementing the first component of construction of National Ecosystem Restoration Plan.

A programmatic BA was prepared in 2004 for the LCA Ecosystem Restoration Study (USACE

2004a). This proposed Project is an outgrowth of the LCA comprehensive programmatic

restoration study. The 2004 programmatic BA is thereby incorporated by reference.

2 DESCRIPTION OF THE STUDY AREA

The TBBSR Project provides for the restoration of the Timbalier and Isles Dernieres barrier

island chains located in Terrebonne Parish and Lafourche Parish, Louisiana. The Study Area is

located in the 3rd Congressional District. The basin is separated from the Gulf of Mexico

(GOM) by a chain of barrier islands, which serve as a natural barrier to storm events and reduce

marine influences on interior wetlands within the basin (Figure 1-1).


2

Figure 1-1. Terrebonne Basin Barrier Shoreline Restoration Study Area.


3

2.1 Isles Dernieres Reach

The Isles Dernieres Reach represents a barrier island arc approximately 22 miles long in

Terrebonne Parish and extends from Caillou Bay east to Cat Island Pass. Raccoon Island,

Whiskey Island, Trinity Island, East Island, and Wine Island, the primary islands that comprise

the Isles Dernieres barrier island chain, are backed by Bay Blanc, Bay Round, Caillou Bay, and

Terrebonne Bay, and bordered by the Gulf of Mexico (GOM) on the seaward side. The islands

range from approximately 0.1 to 0.7 miles wide and are generally composed of a thin sand cap

over a thick mud platform. Elevations are generally low and the islands are frequently

overwashed (USACE 2004c).

The Isles Dernieres have been and continue to be an important commercial and recreational

resource for Louisiana and the nation for more than 150 years. The islands support habitats that

are critical to the State’s commercial fishing industry. Furthermore, the mineral-rich subsurface

below Terrebonne Bay, Lake Pelto, and Timbalier Bay has supported a high concentration of oil

and gas wells.

The first major coastal resort in Louisiana was located here and was washed away by the great

hurricane of 1856 (USACE 2004c). The Isles Dernieres are also the location of five Coastal

Wetland Planning, Protection, and Restoration Act (CWPPRA) projects. These projects

included: Raccoon Island (TE-29), Whiskey Island (TE-27), Trinity Island (TE-24), East Island

(TE-20), and New Cut (TE-37).

2.2 Timbalier Reach

The Timbalier Reach is comprised of Timbalier Island and East Timbalier Island. The two

islands are on the western edge of the Lafourche barrier shoreline and are located about 60 miles

southwest of New Orleans, Louisiana. This barrier island shoreline is approximately 20 miles

long and backed by Terrebonne and Timbalier Bay to the north and delimited by Raccoon Pass

to the east and Cat Island Pass to the west. The islands range from 0.1 to 0.6 miles wide and

have low elevations. The Timbalier Islands support onshore and offshore oil and gas

development and production. Oil and gas production facilities are prevalent along East Timbalier

Island, while only a few scattered facilities are present along Timbalier Island. Oil and gas canals

are present on both islands (USACE 2004c).

3 PURPOSE AND NEED FOR PROJECT

The overarching problem in the Terrebonne Basin barrier islands (hereafter referred to as Study

Area) is a lack of sustainability of the coastal ecosystem, primarily due to coastal land loss.

Natural processes and human actions, such as the construction of oil field canals and the

containment of waterways, have threatened the long-term viability of the Study Area. These

processes and activities have caused significant adverse impacts to the Terrebonne Basin barrier

island shoreline, resulting in extensive barrier island habitat loss and ecosystem degradation

(USACE 2004a). Specific problems in the Study Area include:

•Land loss due to erosion threatens the geomorphic and hydrologic barrier systems

•Longshore sediments are significantly reduced, limiting the ecosystem’s ability to be selfsustaining

•Loss of barrier islands ecosystem habitat


4

• Freshwater wetlands are impacted by increased salinity

3.1 Critical Needs

The critical needs in the Study Area include:

•Restore and/or preserve critical and essential geomorphic structures (beach, dune, ridge, and

marsh) of the Terrebonne Basin barrier system

•Reduce and/or prevent future land loss, habitat loss, and fragmentation of the land features

• Protect vital local, regional, and national socio-economic resources

• Protect the back barrier estuarine environments from the high energy marine processes and

associated salinities of the GOM

•Near-term restoration should be synergistic with future restoration by maintaining or

restoring the integrity of Louisiana’s coastline, upon which all future coastal restoration is

dependent

•Design and operate restoration features that support the development of large-scale, longrange comprehensive coastal restoration

The sustainability of the coastal ecosystems is threatened by the inability of the barrier islands to

maintain geomorphologic functionality. The Isles Dernieres and Timbalier barrier islands are

expected to be impacted by multiple tropical weather events over the next several decades. Each

storm poses the risk of breaching the existing islands. As a result, these barrier islands will

continue to degrade and migrate landward as an increasingly fragmented chain of smaller barrier

islands. The fragmentation of the barrier islands will progressively increase the risk of a single

storm event causing widespread fundamental changes in the hydrodynamics and ecological

function of the interior bay system.

Complete opening of the bays to the unabated effects of storms will increase the volume of open

water and fetch within these bays, decreasing their ecologic value. Ecologic changes will occur

and storm surges will increase, requiring greater levels of flood risk reduction infrastructure in

populated areas. As the islands continue to fragment and migrate northward allowing intrusion

of the GOM, restoration will become progressively more expensive and difficult to implement.

The effects of increased wave and storm energy will increase stress on, and contribute to a

reduction in the vigor and aerial extent of, the remaining wetlands that now serve as a buffer

affording protection against storms to the developed areas located north of the Study Area

(USACE 2008).

3.2 Study Area Opportunities

Opportunities for ecosystem restoration include:

•Restore diversity of the barrier island habitats

• Increase longevity of the barrier island geomorphic function

• Increase sediment into the long-shore process

• Improve the barrier island habitat


5

Many of the above opportunities can be utilized in combination with planned or existing projects

to produce synergistic effects while minimizing disruptions to the surrounding ecosystem and

economy.

3.3 Planning Objectives

The LCA TBBSR study objectives are a localized and project specific delineation of the LCA

objectives. Based on the function of these barrier islands and problems identified for the

Terrebonne islands during this study, the following planning objectives were developed to assist

the development and evaluation of alternative plans.

• Provide an expanded footprint of minimized barrier island section to provide the

geomorphic form and ecologic function of the Terrebonne Basin barrier islands, reducing

volume loss within the LCA TBBSR Study Area below the historic average (1880 through

2005).

•Restore and improve various barrier island habitats that provide essential habitats for fish,

migratory birds, and other terrestrial and aquatic species, mimicking, as closely as possible,

conditions which would occur naturally in the area for the 50 year period of analysis.

• Increase sediment input to supplement long-shore sediment transport processes along the

gulf shoreline by mechanically introducing compatible sediment, and increasing the ability

of the restored area to continue to function and provide habitat for the 50-year period of

analysis with minimum continuing intervention.

3.4 Planning Constraints

Planning constraints relevant to the Project include natural resources limitations such as lack of

suitable sediments for restoration; environmental impacts of human activities in the Study Area;

infrastructure and cultural resources that must be avoided or relocated; and limitations in the

characterization and simulation of environmental processes that determine the effects of

alternatives plans. Barrier shoreline systems are dynamic. Each hurricane and winter season

will impact the shoreline to varying degrees. Breaches created during a hurricane are often

healed through the natural sand transport processes. However, lack of sediment in the

Terrebonne barrier system has limited the natural ability of these breaches to close. Throughout

the study, the team’s analyses attempted to incorporate data related to these changes. However,

the dynamic nature of the shoreline makes it more difficult to accurately simulate and predict the

affects of the various alternatives.

3.5 Purpose

The purpose of the Project is to address the critical near-term need for shoreline restoration in the

Study Area through simulation of historical conditions (USACE 2004a). This would be achieved

by enlarging the existing barrier islands (width and dune crest) and reducing the current number

of breaches. Additional objectives include analyzing the current conditions of the barrier islands,

assessing impacts from the hurricanes of 2005 and 2008, and reaffirming the validity of the

findings of the FPEIS conducted for the 2004 LCA Report (USACE 2004b).


6

4 PROPOSED PROJECT

4.1 National Ecosystem Restoration Plan

The National Ecosystem Restoration (NER) plan consists of Raccoon Island with Terminal

Groin (Plan E), Whiskey Island (Plan C), Trinity Island (Plan C), and Timbalier Island (Plan E).

The plan was selected because it is a Best Buy plan that restores the geomorphologic form and

ecologic function of the four islands in the Terrebonne Basin barrier system. Immediately after

construction (TY1), the NER will add 3,283 acres of habitat (dune, intertidal, and supratidal) to

the existing island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing the

total size of the islands to 5,840 acres. This includes approximately 472 acres of dune, 4,320

acres of supratidal habitat, and 1,048 acres of intertidal habitat. The NER plan is presented in

Figure 4-1.

Figure 4-1. The National Ecosystem Restoration Plan

The creation of dune, supratidal, and intertidal habitats will provide essential habitats for fish,

migratory birds, and other terrestrial and aquatic species. Furthermore, by using the proposed

borrow areas, the project would increase sediment input to supplement long-shore sediment

transport processes along the gulf shoreline by mechanically introducing compatible sediment,

and increasing the ability of the restored area to continue to function and provide habitat with

minimum continuing intervention. The plan also represents a system-wide and cost effective

approach of restoring as many islands within the Terrebonne Basin barrier system which are

constructible with available sediment sources.

Each of the islands in the NER plan will require at least one renourishment event in order to

maintain their geomorphologic form and ecologic function throughout the 50-year period of

analysis. The renourishment quantities and sequencing are provided in Table 4-1. Marsh

renourishment was not included since the initial restoration plan provides for significant


7

intertidal habitat throughout the 50 year period of analysis. The resulting habitat acres, including

renourishment benefits, are provided in Table 4-2.

Table 4-1. Renourishment Sequencing and Quantities.

Island Plan Renourishment Year Renourishment Plan

Raccoon Plan E w/ TG TY30 Restore Plan B

TY20 Add Plan C

Whiskey Plan Ca

TY40 Add Plan B

Trinity Plan C TY25 Add Plan C

Timbalier Plan E TY30 Restore Plan B

a Whiskey would require two renourishments, one at TY20 and one at TY40


8

Table 4-2. Summary of Habitat Values for the NER Plan

Habitat Acres

Island Habitat Type

TY0

2012

TY1

2013

TY5

2017

TY10

2022

TY20

2032

TY21

2033

TY25

2037

TY26

2038

TY30

2042

TY31

2043

TY40

2052

TY41

2053

TY50

2062

Dune 0 63 50 29 20 18 10 8 0 45 15 14 3Supratidal 51 688 678 659 650 603 416 369 182 204 165 166 170Intertidal 188 38 39 40 39 82 253 295 466 468 486 484 468

Raccoonw/TG Plan E

Total 239 789 767 728 709 703 679 672 648 717 666 664 641

Dune 0 65 61 57 0 65 61 61 57 51 0 57 0Supratidal 377 830 328 223 84 496 375 344 223 209 84 387 164Intertidal 443 377 808 828 847 834 782 769 717 693 472 461 363

WhiskeyPlan C

Total 820 1272 1197 1108 931 1395 1218 1174 997 953 556 905 527

Dune 39 129 122 67 0 0 0 129 122 113 34 30 0Supratidal 232 456 316 270 190 170 90 496 320 311 230 216 90Intertidal 311 564 632 635 594 595 597 590 561 543 380 362 199

TrinityPlan C

Total 582 1149 1070 972 784 765 687 1215 1003 967 644 608 289

Dune 57 215 183 160 0 0 0 0 0 155 13 12 0Supratidal 549 2346 2257 2130 1996 1859 1313 1176 629 667 524 495 236Intertidal 374 69 71 74 76 183 612 719 1148 1146 1123 1120 1088

TimbalierPlan E

Total 979 2630 2511 2364 2072 2043 1925 1895 1777 1968 1660 1626 1324

Dune 95 472 416 313 20 83 71 198 179 364 62 113 3Supratidal 1209 4320 3579 3282 2920 3129 2193 2385 1354 1391 1003 1264 660Intertidal 1315 1048 1550 1577 1556 1694 2244 2373 2892 2849 2461 2427 2118

Total

Total 2619 5840 5545 5172 4496 4905 4508 4956 4425 4604 3526 3803 2781


9

4.2 First Component of Construction

The NER plan, which consists of Whiskey Plan C, Trinity Plan C, Raccoon Plan E with

Terminal Groin, and Timbalier Plan E was selected as the NER because it was a Best Buy that

fulfills the planning objectives of the project. The plan also represents a system-wide and cost

effective approach of restoring as many islands within the Terrebonne Basin barrier system

which are constructible with available sediment sources. However, the NER plan cannot be

constructed under the current WRDA 2007 authorization. Therefore, a subset of the NER plan is

recommended as the first component of construction.

In order to identify the first component of construction from the NER plan, the PDT performed

separate cost refinements on each island in the NER using MCACES Second Generation (MII).

The original contingency was also refined using Crystal Ball. These refinements inflated the

costs of the islands, leaving Trinity Island Plan C and Whiskey Island Plan C as the only islands

plans that could be constructed within the budget. Consequently, a separate screening process

was conducted on the two islands to select the most appropriate island for the first component of

construction.

Although Whiskey Plan C provides slightly fewer AAHUs than Trinity Island Plan C (379

AAHUs vs. 387 AAHUs), it was selected as the first component of construction due to a number

of qualitative benefits provided by the plan. For example, Whiskey Plan C was designed to

avoid approximately 286 acres of existing mangroves on the island in order to minimize the

ecologic impact during construction. The plan will restore a total of 1,272 acres of dune,

supratidal, and intertidal habitat on the Terrebonne Basin Barrier Shoreline. Since the island is

considered a valuable wildlife habitat (Isles Dernieres Barrier Islands Wildlife Refuge) and the

LDWF is reestablishing a pelican rookery on the island, maintaining adequate areas of healthy

beach, dune, and marsh is particularly important. The island is also a critical habitat for

endangered species including the piping plover and is a valuable stopover habitat for migratory

birds.

The initial construction of Whiskey Island is estimated to take 447 days to complete. This

includes beach, dune, and marsh fill activities. As seen in Table 4-1, Whiskey Island Plan C will

require two renourishment intervals. The first would occur at TY20 and would include the

addition of the same amount of dune and supratidal beach habitat that was originally created in

TY1 (i.e. add a Plan C to the template at TY20). The second renourishment interval would occur

at TY 40 and would include the addition of the same amount of dune and supratidal beach

habitat needed to construct a Plan B template. The resulting habitat acres, including

renourishment benefits, are provided in Table 4-2.

4.3 Components

The following sections detail the proposed templates for each of the four islands in the NER

plan, including Whiskey Island Plan C, which was selected as the first component of

construction.

4.3.1 Raccoon Island Plan E with Terminal Groin

Raccoon Plan E proposes a dune height of +7.7 feet NAVD 88 with a dune crown width of 100

feet. The dune elevation takes into account that there will be approximately 1.7 feet of vertical

adjustments (eustatic sea level rise, subsidence, and compaction) occurring during the first six


10

months after construction. At the end of the six-month period, the dune should reach the design

elevation of 6 feet NAVD 88. The dune elevation is considerably higher than that of Trinity and

Whiskey because the plan is design to withstand 25 years of additional background erosion

rather than just 5 years. Furthermore, the thickness of the 25-year plan (Plan E) results in a

higher compaction rate.

The slopes of the beach and dune are set 60:1 and 30:1 (horizontal to vertical), respectively. The

marsh fill is proposed on the landward side of the dune at an elevation of +3.7 feet NAVD 88. As

with the dune elevation, the marsh elevation is higher than that of Whiskey and Trinity because it

is designed withstand a longer duration of background erosion.

Immediately after construction (TY1), the Raccoon Plan E will add 554 acres of habitat (dune,

intertidal, and supratidal) to the existing 235-acre island footprint, increasing the size of the

island to 789 acres. This includes 63 acres of dune, 688 acres of supratidal, and 38 acres of

intertidal habitat.

Eight detached and segmented breakwaters were constructed as part of a CWPPRA project (TE29) in 1997. The breakwaters were installed to reduce shoreline retreat, promote sediment

deposition along the beach, and to protect shorebird habitat. Due to the success of the TE-29

breakwaters, eight additional breakwaters were constructed as part of a separate CWPPRA

project (TE-48) that was completed in 1997. The breakwaters were installed west of the original

breakwaters. TE-48 also included the creation of approximately 60 acres of emergent and

intertidal back-barrier marsh.

Raccoon Plan E was designed to complement the intertidal marsh created as part of TE-48. Plan

E was also designed to avoid approximately 58 acres of existing mangroves immediately

adjacent to and gulfward of TE-48 (Figure 4-2).

The restoration plan for Raccoon Island (the western-most island), will include the construction

of a terminal groin. The terminal groin will be approximately 1200 feet long and 75 feet wide

and will be installed at the western terminus of the template to prevent sediment migration out of

the Isle Dernieres system. The sediment that moves off of Raccoon Island to the west is lost to

the shoals and buried by the mud stream from the Atchafalaya, so a terminal groin on Raccoon

Island will not starve another island. Apart from the terminal groin, the natural long-shore

sediment transport mechanisms within the Isles Deneries and Timbalier Islands would not be

altered by the Project.

Fill quantities for the dune/beach and marsh components of Raccoon Plan E are 5.2 million and

5.1 million cubic yards, respectively. The plan will utilize beach/dune material from Ship Shoal

and marsh material from the Raccoon Island TE-48 borrow area. However, the borrow area does

not have enough material to construct the marsh in its entirety. Therefore, approximately 2.7

million cubic yards of sand will be dredged from Ship Shoal to provide a base layer for the

marsh. The marsh material from the Raccoon Island TE-48 borrow area will be deposited on the

sand material to provide an adequate foundation for the marsh.

For the dune area, the material will be pumped from the dredge to the beach. The material will

then be worked on the beach by bulldozers and front-end loaders. For the marsh area, the

material will be pumped from the offshore borrow site. Containment dikes will be constructed

around the perimeter. Sediment for the containment dikes will be dredged from existing material

inside the marsh creation area. These operations will be completed in a manner that will


11

minimize turbidity of the water at the dredge site and the discharge site. The initial construction

of Raccoon Island is estimated to take 454 days to complete. This includes beach, dune, and

marsh fill activities as well as the construction of the terminal groin. Figure 4-2 presents the plan

view of Raccoon Plan E the proposed terminal groin.

Approximately 11,912 feet of sand fencing will be installed to promote deposition of windblown

sand, create dune features, reduce trampling of existing dunes by beach visitors, and protect

vegetative plantings. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-foot centers.

Figure 4-2. Raccoon Island Plan E with Terminal Groin

4.3.2 Whiskey Island Plan C

Whiskey Island Plan C, which is one of the four islands in the NER plan, was also selected as the

first component of construction . The plan proposes a dune height of +6.4 feet NAVD 88 with a

dune crown width of 100 feet. The dune elevation takes into account that there will be

approximately 0.4 feet of vertical adjustments (eustatic sea level rise, subsidence, and

compaction) occurring during the first six months after construction. At the end of the six-month

period, the dune should reach the design elevation of 6 feet NAVD 88. The slopes of the beach

and dune are set 60:1 and 30:1 (horizontal to vertical), respectively.

The marsh fill is proposed on the landward side of the dune at an elevation of +2.4 feet NAVD

88. Although the design elevation for the marsh is 1.6 feet NAVD 88, the marsh will be

constructed at a higher elevation to account for initial vertical adjustments.

The plan will utilize beach/dune material from the Ship Shoal borrow area and marsh material

from Whiskey 3a borrow area. Fill quantities for the initial construction of the dune/beach and


12

marsh components of Whiskey Plan C are 8.3 million and 0.6 million cubic yards, respectively.

For the dune area, the material will be pumped from the dredge to the beach. The material will

then be worked on the beach by bulldozers and front-end loaders. For the marsh area, the

material will be pumped from the offshore borrow site. Containment dikes will be constructed

around the perimeter. Sediment for the containment dikes will be dredged from existing material

inside the marsh creation area. These operations will be completed in a manner that will

minimize turbidity of the water at the dredge site and the discharge site. The initial construction

of Whiskey Island is estimated to take 447 days to complete. This includes beach, dune, and

marsh fill activities. Figure 4-3 presents the plan view of Whiskey Plan C.

Approximately 18,075 feet of sand fencing will be installed. The sand fences are porous barriers

that reduce wind speed along the coast such that sand being transported by the wind accumulates

on the downwind side of the fence. The sand fences will promote deposition of windblown sand,

create dune features, reduce trampling of existing dunes by beach visitors, and protect vegetative

plantings. Vegetative plantings will include a variety of native species. The recommended

planting density is no greater than 8-foot centers.

Figure 4-3. Whiskey Island Plan C

4.3.3 Trinity Island Plan C

Trinity Plan C proposes a dune height of +6.4 feet NAVD 88 with a dune crown width of 100

feet. The dune elevation takes into account that there will be approximately 0.4 feet of vertical

adjustments (eustatic sea level rise, subsidence, and compaction) occurring during the first six

months after construction. At the end of the six-month period, the dune should reach the design

elevation of 6 feet NAVD 88. The slopes of the beach and dune are set 60:1 and 30:1 (horizontal

to vertical), respectively. The marsh fill is proposed on the landward side of the dune at an

elevation of +2.5 feet NAVD 88, which is slightly higher than the dune elevation at Whiskey.

Due to the existing topography of Trinity Island, the required marsh fill thickness is greater and


13

thus results in a higher compaction rate. As with Whiskey Island, the dune and marsh elevations

account for vertical adjustments occurring after the first six months of construction.

Immediately after construction (TY1), the Trinity Plan C will add 585 acres of habitat (dune,

intertidal, and supratidal) to the existing 564-acre island footprint, increasing the size of the

island to 1,149 acres. This includes 129 acres of dune, 456 acres of supratidal, and 564 acres of

intertidal habitat.

Trinity Plan C will utilize beach/dune material from Ship Shoal and marsh material from the

Whiskey 3A borrow area. Fill quantities for the dune/beach and marsh components of Trinity

Plan C are 3.1 million and 4.0 million cubic yards, respectively. For the dune area, the material

will be pumped from the dredge to the beach. The material will then be worked on the beach by

bulldozers and front-end loaders. For the marsh area, the material will be pumped from the

offshore borrow site. Containment dikes will be constructed around the perimeter. Sediment for

the containment dikes will be dredged from existing material inside the marsh creation area.

These operations will be completed in a manner that will minimize turbidity of the water at the

dredge site and the discharge site. The initial construction of Trinity Island is estimated to take

484 days to complete. This includes beach, dune, and marsh fill activities. Figure 4-4 presents

the plan view of Trinity Plan C.

Figure 4-4. Trinity Island Plan C

Approximately 22,467 feet of sand fencing will be installed to promote deposition of windblown

sand, create dune features, reduce trampling of existing dunes by beach visitors, and protect

vegetative plantings. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-foot centers.


14

4.3.4 Timbalier Island Plan E

Timbalier Plan E proposes a dune height of +7.1 feet NAVD 88 with a dune crown width of 100

feet. The dune elevation takes into account that there will be approximately 1.1 feet of vertical

adjustments (eustatic sea level rise, subsidence, and compaction) occurring during the first six

months after construction. At the end of the six-month period, the dune should reach the design

elevation of 6 feet NAVD 88. The slopes of the beach and dune are set 60:1 and 30:1 (horizontal

to vertical), respectively. The marsh fill is proposed on the landward side of the dune at an

elevation of +3.2 feet NAVD 88. As with Raccoon Island Plan E, the elevations of the plan are

larger than that of Trinity and Whiskey because it is designed to withstand a longer period of

background erosion. Furthermore, the larger plans are thicker and thus exhibit higher

compaction rates.

Immediately after construction (TY1), the Timbalier Plan E will add 1,675 acres of habitat

(dune, intertidal, and supratidal) to the existing 955-acre island footprint, increasing the size of

the island to 2,630 acres. This includes 215 acres of dune, 2,346 acres of supratidal, and 69 acres

of intertidal habitat.

Fill quantities for the dune/beach and marsh components of Timbalier Plan E are 10.7 million

and 9.1 million cubic yards, respectively. Timbalier Plan E will utilize beach/dune material from

South Pelto and marsh material from Whiskey 3A (marsh material). However, the marsh borrow

areas do not have adequate material to construct the marsh in its entirety. Therefore,

approximately 8.6 million cubic yards of sand will be dredged from South Pelto, Whiskey 3A

(sandy material), and New Cut to provide a base layer for the marsh. The marsh material from

Whiskey 3A will be deposited on the sand material to provide an adequate foundation for the

marsh.

For the dune area, the material will be pumped from the dredge to the beach. The material will

then be worked on the beach by bulldozers and front-end loaders. For the marsh area, the

material will be pumped from the offshore borrow site. Containment dikes will be constructed

around the perimeter. Sediment for the containment dikes will be dredged from existing material

inside the marsh creation area. These operations will be completed in a manner that will

minimize turbidity of the water at the dredge site and the discharge site. The initial construction

of Timbalier Island is estimated to take 1,095 days to complete. This includes beach, dune, and

marsh fill activities. Figure 4-5 presents the plan view of Timbalier Plan E.

Approximately 35,425 feet of sand fencing will be installed to promote deposition of windblown

sand, create dune features, reduce trampling of existing dunes by beach visitors, and protect

vegetative plantings. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-foot centers.


15

Figure 4-5. Timbalier Island Plan E


16

5 DESCRIPTION AND STATUS OF SPECIES

There are twenty-nine animals and three plant species, under the jurisdiction of the U.S. Fish and

Wildlife Service (USFWS) and/or the National Marine Fisheries Service (NMFS), presently

classified as threatened or endangered within the state of Louisiana (Table 5-1). Based on a letter

from USFWS to the U.S. Army Corps of Engineers dated March 2010 (USFWS 2010a),

Federally listed threatened/endangered species occurring in the Study Area include the piping

plover, West Indian manatee, loggerhead sea turtle, Kemp’s Ridley sea turtle, green sea turtle,

leatherback sea turtle, and hawksbill sea turtle. The USFWS also identified the Brown Pelican

and colonial nesting waterbirds as species of special interest within the Study Area. The USFWS

letter is provided in Annex A1.

Compliance with the ESA (7 U.S.C. 136; 16 U.S.C. 460 et seq.) has been coordinated

with the USFWS and the NMFS for those species under their respective

jurisdictions. The use of recommended primary activity exclusion zones and timing

restrictions would be utilized, to the maximum extent practicable, to avoid project

construction impacts to any threatened or endangered species or their critical

habitat within the Study Area. The USACE will continue to closely coordinate and

consult with the USFWS and the NMFS regarding threatened and endangered

species under their jurisdiction that may be potentially impacted by the proposed

action. Although the West Indian manatee and the Hawksbill, Kemp’s ridley,

Leatherback, Loggerhead, and Green sea turtles may be found in the Study Area,

the only endangered species with a high potential for adverse impacts from the

proposed project is the piping plover. Multi-project research is currently underway

to determine the potential for diversion impacts to this species. Formal

consultation on the piping plover has been conducted and the USFWS has issued a

Biological Opinion (Annex A2). The USACE has agreed to comply with the RPM and

the terms and conditions outlined in the Biological Opinion.

In September of 2010, the USFWS provided a draft version of the USFWS Coordination Act

Report (FWCAR). The report reiterated the status of the threatened and endangered species in

the study area as well as the species of special Interest (USFWS, 2010c). Furthermore, the

USFWS provided recommendations for minimizing impacts to these species during construction.

These recommendations will be implemented to the fullest extent practicable. All construction

and renourishment activities will be conducted in close coordination with USFWS as well as

LDWF.


17

Table 5-1. Threatened and Endangered Species in Louisiana

Classification Species Scientific Name Status Jurisdiction Found in Study Area?

Florida Panther1 Felis concolor coryl Endangered USFWS No

Red Wolf1 Canis rufus Endangered USFWS No

West Indian Manatee Trichechus manatus Endangered USFWS Yes

Mammals

Louisiana Black Bear Ursus americanus luteolus Threatened USFWS No

Bachman’s Warbler2 Vermivora bachmanii Endangered USFWS No

Eskimo Curlew1 Numenius borealis Endangered USFWS No

Ivory-billed Woodpecker1 Campephilus principalis Endangered USFWS No

Least Tern; interior population Sterna antillarum Endangered USFWS No

Red-cockaded Woodpecker Picoides borealis Endangered USFWS No

Birds

Piping Plover Charadrius melodus Threatened USFWS Yes

Hawksbill Sea Turtle Eretomchelys imbricate Endangered USFWS/NMFS Yes

Kemp’s (Atlantic) Ridley Sea Turtle Lepidochelys kempii Endangered USFWS/NMFS Yes

Leatherback Sea Turtle Dermochelys coriacea Endangered USFWS/NMFS Yes

American Alligator3 Alligator mississippiensis Threatened USFWS No

Gopher Tortoise Gopherus polyphemus Threatened USFWS No

Green Sea Turtle Chelonia mydas Threatened USFWS/NMFS Yes

Loggerhead Sea Turtle Caretta caretta Threatened USFWS/NMFS Yes

Ringed Sawback Turtle Graptemys oculifera Threatened USFWS No

Reptiles

Snake, Louisiana Pine Pituophis ruthveni Candidate4 USFWS No

Pallid Sturgeon Scaphirhynchus albus Endangered USFWS No

Gulf Sturgeon Acipenser oxyrinchus desotoi Threatened USFWS/NMFS No

Dusky Shark Carcharhinus obscurus Candidate4 NMFS No

Sand Tiger Shark Odontaspis Taurus Candidate4 NMFS No

Night Shark Carcharinus signatus Candidate4 NMFS No

Fish

Speckled hind Epinephelus drummondhayi Candidate4 NMFS No


18

Classification Species Scientific Name Status Jurisdiction Found in Study Area?

Saltmarsh topminnow Fundulus jenkensi Candidate4 NMFS No

Jewfish Epinephelus itajara Candidate4 NMFS No

Warsaw Grouper Epinephelus striatus Candidate4 NMFS No

Mussel, Fat Pocketbook Potamilus capax Endangered USFWS No

Pink pearlymussel Mucket Lampsilis abrupta Endangered USFWS No

Inflated (Alabama) Heelsplitter Potamilus inflatus Threatened USFWS No

Invertebrates

Louisiana Pearlshell Margaritifera hembeli Threatened USFWS No

Sperm Whale Physeter macrocephalus Endangered NMFS No

Sei Whale Balaenoptera borealis Endangered NMFS No

Humpback Whale Megaptera novaeangliae Endangered NMFS No

Finback Whale Balaenoptera physalus Endangered NMFS No

Marine

Mammals

Blue Whale Balaenoptera musculus Endangered NMFS No

American Chaffseed Schwalbea Americana Endangered USFWS No

Louisiana Guillwort Isoetes louisianensis Endangered USFWS No Plants

Earth Fruit Geocarpon minimum Threatened USFWS No

1 The Florida panther, red wolf, Eskimo curlew, and ivory-billed woodpecker are presumed to be extinct in the state.2 There has been no confirmed Bachman’s warbler U.S. nesting ground sighting since the mid-1960s, however, several sightings of the species have occurred onwintering grounds during the last decade. This species may be extirpated in Louisiana.3 For law enforcement purposes, the alligator in Louisiana is classified as "Threatened due to Similarity of Appearance." They are biologically neitherendangered nor threatened. Regulated harvest is permitted under state law.4 Candidate species are not protected under the ESA, but concerns about their status indicate that they may warrant listing in the future. Federal agencies and thepublic are encouraged to consider these species during project planning so that future listings may be avoided.


19

The following sections provide the federal status, species descriptions, and habitat information

for the threatened/endangered species found within the Project Boundary of the NER plan. The

Project Boundary refers to each of the four island in the NER plan (which includes the first

component of construction) as well as the borrow areas used in their construction. Much of this

information was adapted from the Biological Assessment conducted for the Barataria Basin

Barrier Shoreline (BBBS) Restoration Feasibility Study (USACE 2009) and CWPPRA Project

TE-50 (USEPA 2009). The BBBS project was considered to be directly applicable because the

project proposes similar restoration efforts for barrier islands near the Project Boundary. The

CWPPRA Project was constructed on Whiskey Island in 2009 and was therefore considered

applicable to the TBBSR Project. Colonial nesting birds and the Brown Pelican are also

discussed since they are Species of Interest that are found within the Project Boundary.

5.1 Piping Plover

The piping plover, (Charadrius melodus), is a small shorebird approximately seven inches in

length with a wingspan of approximately fifteen inches and weighs from 1.5 to 2 ounces. It is

sand-colored on the back with white undersides. The piping plover is distinguished from similar

species by its bright orange legs. During the breeding season, the plover has a single black band

across its breast and forehead, which are absent during the winter.

The piping plover is named for its melodic mating call. It is a small, pale-colored North

American shorebird. The bird’s light sand-colored plumage blends in with sandy beaches and

shorelines. There are three populations of piping plovers in the United States. The most

endangered is the Great Lakes breeding population, which encompasses only thirty-two breeding

pairs. The Northern Great Plains and Atlantic Coast populations are classified as threatened and

include 1398 and 1372 breeding pairs, respectively. All piping plovers winter along the southeast

and Gulf coasts and are classified as threatened in their wintering habitat (USFWS 2000). Major

threats to the piping plover include the loss and degradation of habitat due to development,

disturbance by humans and pets, and predation.

As seen in Figure 5-1, the historical breeding range in North America of the piping plover

included the Atlantic coastal beaches from Newfoundland to South Carolina; beaches of the

Great Lakes; and the northern Great Plains region from Alberta to Ontario and south to Nebraska

(USFWS 2000). These populations were reported to winter along the GOM, the Atlantic coast

from North Carolina to Florida, eastern Mexico, and in the Caribbean Islands (Haig and Oring

1985). Approximately thirty-five percent of the total breeding piping plover population winters

along the Gulf coast from Florida to Texas and represents fifty-six percent of the Great

Lakes/Great Plains population (Nicholls and Baldassarre 1990).

The population potentially occurring within the Project Boundary is the Great Lakes population.

They arrive from their northern breeding grounds as early as late July and may be present for

eight to ten months of the year.


20

Figure 5-1. Distribution of Piping Plover Populations (USFWS 2000)

Northward migration to the breeding grounds occurs during late February, March, and early

April (Patterson 1988, MacIvor et al. 1990). Plovers will breed at one year of age (MacIvor

1990, Haig 1992) and are monogamous, but usually shift mates from year to year (Wilcox 1959,

Haig and Oring 1988, MacIvor et al. 1990).

Southward migration to the wintering grounds along the southern Atlantic coast and GOM

shoreline extends from late July through September. Individuals can be found on their wintering

grounds throughout the year but sightings are rare in May, June, and early July (USFWS 1996).

Ideal wintering habitat for the piping plover on the Gulf of Mexico coast would contain large

sand flats or sand-mud flats adjacent to a tidal pass or tidal inlet (Haig and Oring 1985, Nicholls

1989). A thin layer of mud covering the sand seems to attract plovers, due to possible food or

refuge association (Nicholls 1989). Nicholls observed that barrier beaches with over wash areas

or sections of old marshes also attract plovers. A gulf-facing beach having a very low gradient,

thus an increased intertidal zone, offers an almost equally attractive area (Haig and Oring 1985).

Also piping plovers will inhabit spoil islands on the Gulf Intracoastal Waterway on both Atlantic

and Gulf Coasts. Winter 2001 census observations were in the following habitat types: mudflats

(36.3%), sandy beaches (33.2%), sand/salt flats (23.1%) algal mats (2.8%), oyster reefs (1.0%)

and gravel shores (0.1%; Haig 2004).

Piping plovers feed extensively on intertidal beaches, mudflats, sand flats, algal flats, and washover passes with no or very sparse emergent vegetation; they also require unvegetated or sparsely

vegetated areas for roosting. Roosting areas may have debris, detritus, or micro-topographic

relief offering refuge from high winds and cold weather. In most areas, wintering piping plovers

are dependent on a mosaic of sites distributed throughout the landscape, because the suitability

of a particular site for foraging or roosting is dependant on local weather and tidal conditions.

Plovers move among sites as environmental conditions change. The primary constituent elements

for piping plover wintering habitat are those habitat components that support foraging, roosting,

and sheltering and the physical features necessary for maintaining the natural processes that

support those habitat components. Constituent elements are found in geologically dynamic


21

coastal areas that contain intertidal beaches and flats (between annual low tide and annual high

tide), and associated dune systems and flats above annual high tide. Important components (or

primary constituent elements) of intertidal flats include sand and/or mud flats with no or very

sparse emergent vegetation. Adjacent unvegetated or sparsely vegetated sand, mud, or algal flats

above high tide are also important, especially for roosting plovers (USEPA 2006)

In July of 2001, the USFWS designated specific areas in the United States as critical habitat for

wintering piping plovers (Federal Register / Vol. 66, No. 132, 10 July 2001). Piping plover

critical habitat is defined by the USFWS as “those elements essential for the primary biological

needs of foraging, sheltering, roosting, and the physical features necessary for maintaining the

natural processes that support those habitat components.” The USFWS also indicated that

constituent elements are found in geologically dynamic coastal areas that contain intertidal

beaches and flats (between annual low tide and annual high tide), and associated dune systems

and flats above annual high tide. Important primary constituent elements of intertidal flats

include sand and/or mud flats with no or very sparsely emergent vegetation. Adjacent

unvegetated or sparsely vegetated sand, mud, or algal flats above high tide are also important,

especially for roosting plovers (USFWS, 2001). The USFWS designated a total of 1,798 miles

(165,211 acres) of shoreline along the GOM and Atlantic coasts as critical wintering habitat.

Critical habitat in Louisiana encompasses 24,950 acres along 342.5 miles of shoreline, which is

most of the coast of Louisiana. The critical habitat designations within Louisiana include:

•Unit LA-1: Texas/Louisiana border to Cheniere au Tigre. 6,548 acres in Cameron and

Vermilion Parishes

•Unit LA-2: Atchafalaya River Delta. 2,276 acres in St. Mary Parish, LA

•Unit LA-3: Point Au Fer Island. 482 acres in Terrebonne Parish.

•Unit LA-4: Isles Dernieres. 1,964 acres in Terrebonne Parish

•Unit LA-5: Timbalier Island to East Grand Terre Island. 5,735 acres in Terrebonne,

Lafourche, Jefferson, and Plaquemines Parishes.

•Unit LA-6: Mississippi River Delta. 259 acres in Plaquemines Parish, LA.

•Unit LA-7: Breton Islands and Chandeleur Island Chain. 7,700 acres in Plaquemines and St.

Bernard Parishes, LA

The NER plan occurs within critical habitat designation Unit LA-4 and LA-5. Critical habitat

acreages for Raccoon, Whiskey, Trinity, and Timbalier Island are summarized in Table 5-1 and

visually delineated on Figures 5-2 through 5-5.

Table 5-2. Critical Habitat Acreages for the NER Plan

Island Critical Habitat (acres)1

Raccoon Island 171

Whiskey Island 269

Trinity Island 303

Timablier Island 572

Total NER Plan 1315

1

Based on 2008 USGS aerial photography


22

Figure 5-2. Piping Plover Critical Habitat on Raccoon Island

Figure 5-3. Piping Plover Critical Habitat on Whiskey Island


23

Figure 5-4. Piping Plover Critical Habitat on Trinity Island

Figure 5-5. Piping Plover Critical Habitat on Timbalier Island


24

5.2 West Indian Manatee

The West Indian manatee (Trichechus manatus) was Federally-listed as an endangered species in

March 11, 1967. The species is further protected as a depleted stock under the Marine Mammal

Protection Act of 1972 (16 U.S.C. 1361-1407).

Manatees are marine mammals that inhabit marine, estuarine, and freshwater environments.

They utilize freshwater runoff sites and springs for drinking water; secluded canals, embayments,

and lagoons for resting, cavorting, procreating, and raising young; and open waterways for

traveling. Preferred feeding areas include shallow seagrass beds near deep channels and smooth

cordgrass beds in salt marshes. Because they are a subtropical species, they are adversely

affected by cold weather and are susceptible to “cold stress syndrome”. During periods of

intense cold, they seek out warm-water refuges including springs and warm-water discharge

pipes from industrial facilities (USFWS 2010b).

Manatees occasionally enter in Lakes Pontchartrain and Maurepas. Sightings appear to be

increasing, and they have been regularly reported in the Amite, Blind, Tchefuncte, and Tickfaw

Rivers, and in canals within the adjacent coastal marshes of Louisiana. They have also been

occasionally observed elsewhere along the Louisiana Gulf coast (USFWS 2010c).

Although manatee sightings are increasing locally, global populations of manatees have declined

in numbers due to collisions with boats and barges, entrapment in flood control structures,

poaching, habitat loss, and pollution. Cold weather and outbreaks of red tide may also adversely

affect these animals. Adult manatees typically give birth to a single calf every two to five years.

Because of their low reproductive rate, manatees are less capable of rebounding from adverse

environmental impacts (USFWS 2010b).

5.3 Hawksbill Sea Turtle

The Hawksbill sea turtle (Eretomchelys imbricate) was listed as an endangered species

throughout its range on June 2, 1970. It is one of seven species of sea turtles found throughout

the world. One of the smaller sea turtles, it has overlapping scutes (plates) that are thicker than

those of other sea turtles. This protects them from being battered against sharp coral and rocks

during storm events. Adults range in size from thirty to thirty-six inches (0.8- 1.0 meters)

carapace length, and weigh 100 to 200 pounds (45-90 kilograms). Its carapace (upper shell) is an

attractive dark brown with faint yellow streaks and blotches and a yellow plastron (under shell).

The name "hawksbill" refers to the turtle's prominent hooked beak.

The hawksbill sea turtle is one of the most infrequently encountered sea turtles in offshore

Louisiana. However, a hawksbill was reported near Calcasieu Lake in 1986. Hawksbills

generally inhabit coastal reefs, bays, rocky areas, passes, estuaries, and lagoons, where they are

found at depths of less than seventy feet. Nesting occurs on undisturbed, deep-sand beaches,

from high-energy ocean beaches to tiny pocket beaches several meters wide bounded by crevices

of cliff walls; these beaches are typically low-energy, with woody vegetation near the waterline.

In the continental United States, nesting sites are restricted to Florida where nesting is sporadic at

best (NMFS /USFWS 1993). Due to the lack of suitable foraging and nesting habitats, there is a

low probability of this species occurring within the Project area.


25

5.4 Kemp’s Ridley Sea Turtle

On December 2, 1970, the Kemp's ridley sea turtle (Lepidochelys kempii) was designated as

endangered across its entire range (35 FR 18319). Critical habitat has been proposed, but has not

been finalized to date.

The Kemp's ridley is the rarest, most endangered, and enigmatic of all sea turtles world-wide

(Perrine 2003; Spotila 2004). Although this small sea turtle has continued to decline in

Louisiana, it is still believed to be the most frequently encountered (Dundee and Rossman 1989),

if not the most abundant sea turtle, off the Louisiana coast (Viosca 1961).

The Kemp's ridley has the most limited distribution of any sea turtles except the Australian

flatback (Perrine 2003). For the most part, breeding is confined to a limited stretch of beach on

the Gulf coast of Mexico. The known range of this species includes the GOM and the Atlantic

Ocean. The current range for Kemp’s ridley in the United States includes marine habitat of the

following coastal states: Georgia, Florida, Alabama, Mississippi, Louisiana, and Texas.

Inshore areas of the GOM appear to be important habitat for Kemp’s ridleys, as they tend to

concentrate around the mouths of major rivers (Frazier 1980). Members of this genus are

characteristically found in waters of low salinity and high turbidity and organic content, where

shrimp are abundant (Zwinenberg 1977; Hughes 1972 as cited in Frazier 1980). Kemp’s ridleys

have been collected in Louisiana from Lake Borgne, Barataria and Terrebonne Bays, and near

Calcasieu Pass (Dundee and Rossman 1989).

Occurrence of these sea turtles in bays and estuaries along the Louisiana coast would not be

unexpected, as many of their primary food items occur there. Stomach analyses of specimens

collected in shrimp trawls off Louisiana revealed crabs, gastropods, and clams (Dobie et al.

1961). Although Kemp’s ridleys are considered primarily carnivorous benthic feeders (Ernst and

Barbour 1972), jellyfish as well as by-catch from shrimp trawlers have been reported as part of

their diet (Landry 1986).

5.5 Leatherback Sea Turtle

The leatherback sea turtle (Dermochelys coriacea) was listed as an endangered species

throughout its range on June 2, 1970 (35 FR 8491). Critical habitat was designated on September

26, 1978 (43 FR 43688), March 23, 1979 (44 FR 17710), and March 23, 1999 (64 FR 14051).

Critical habitat has been designated for shoreline and adjacent waters of the U.S. Virgin Islands

(50 CFR 17.95; 50 CFR 226.207). The leatherback is found throughout the tropical waters of the

Atlantic, Pacific, and Indian Oceans (Ernst and Barbour 1972), the GOM, and the Caribbean

(Carr 1952). Critical habitat for the leatherback includes the waters adjacent to Sandy Point, St.

Croix, U.S. Virgin Islands, up to and inclusive of the waters from the hundred fathom curve

shoreward to the level of mean high tide with boundaries at 17°42'12" N and 64°50'00" W. This

turtle exhibits seasonal fluctuations in distribution in response to the Gulf Stream and other warm

water features (Pritchard 1971; Fritts et al. 1983). During the summer, leatherbacks tend to be

found along the east coast of the U.S. from the Gulf of Maine south to mid-Florida.

Nesting occurs from February through July at sites located from Georgia to the U.S. Virgin

Islands. Nesting leatherbacks occur along beaches in Florida, Nicaragua, and islands in the West

Indies; however, no nesting has been reported in Louisiana (Gunter 1981; Dundee and Rossman

1989). In Louisiana, leatherbacks are believed to occur offshore in deep waters; however, they


26

have been collected from or sighted in Cameron Parish, Atchafalaya Bay, Timbalier Bay, and

Chandeleur Sound (Dundee and Rossman 1989).

Leatherback turtles are omnivorous but feed primarily on jellyfish and other cnidarians, and have

been associated with large schools of cabbage head jellyfish (Stomolophus meleagris). Fritts et

al. (1983) reported that these turtles also ingest plastic, apparently mistaking it for food.

The leatherback is found throughout the tropical waters of the Atlantic, Pacific, and Indian

Oceans (Ernst and Barbour 1972), the GOM, and the Caribbean (Carr 1952). Critical habitat for

the leatherback includes the waters adjacent to Sandy Point, St. Croix, U.S. Virgin Islands, up to

and inclusive of the waters from the hundred fathom curve shoreward to the level of mean high

tide with boundaries at 17°42'12" N and 64°50'00" W. This turtle exhibits seasonal fluctuations

in distribution in response to the Gulf Stream and other warm water features (Pritchard 1971;

Fritts et al. 1983). During the summer, leatherbacks tend to be found along the east coast of the

U.S. from the Gulf of Maine south to mid-Florida.

Nesting occurs from February through July at sites located from Georgia to the U.S. Virgin

Islands. Nesting leatherbacks occur along beaches in Florida, Nicaragua, and islands in the West

Indies; however, no nesting has been reported in Louisiana (Gunter 1981; Dundee and Rossman

1989). In Louisiana, leatherbacks are believed to occur offshore in deep waters; however, they

have been collected from or sighted in Cameron Parish, Atchafalaya Bay, Timbalier Bay, and

Chandeleur Sound (Dundee and Rossman 1989).

Leatherbacks are seriously declining at all major nesting beaches throughout the Pacific. The

decline is dramatic along the Pacific coasts of Mexico, Costa Rica and Malaysia. Nesting along

the Pacific coast of Mexico declined at an annual rate of twenty-two percent over the last twelve

years, and the Malaysian population represents one percent of the levels recorded in the 1950s.

The collapse of those nesting populations was precipitated by a tremendous over-harvest of eggs,

direct harvest of adults, and incidental mortality from fishing. In the Atlantic and Caribbean, the

largest nesting assemblages are found in the U.S. Virgin Islands, Puerto Rico, and Florida.

Nesting data for these locations have been collected since the early 1980s and indicate that the

annual number of nests is likely stable; however, information regarding the status of the entire

leatherback population in the Atlantic is lacking. Nesting activity has also declined in French

Guiana due to erosion of nesting beaches. The population appears to have shifted to Surinam,

where annual numbers of nests rose from less than 100 in 1967 to 5,565 in 1977 and 9,816 in

1987. Current estimates are that 20,000 to 30,000 female leatherbacks exist worldwide.

5.6 Green Sea Turtle

Breeding populations of the green sea turtle (chelonian mydas) in Florida and the Pacific coast of

Mexico are listed as endangered, all others are listed as threatened under the Endangered Species

Act of 1973, as amended, on July 28, 1978 (43 FR 32800). Critical habitat for the green sea turtle

was designated on September 2, 1998 (63 FR 46701); critical habitat was redesignated and

amended on March 23, 1999 (64 FR 14067). Critical habitat has also been designated for waters

surrounding Culebra Island, Puerto Rico (50 CFR 226.208).

Although green sea turtles are found worldwide in oceans and gulfs with water temperatures

greater than 68 ̊F (20 ̊C), their distribution can be correlated to grass bed distribution, location of

nesting beaches, and associated ocean currents (Perrine 2003; Spotila 2004). Long migrations are

often made between feeding and nesting grounds (Carr and Hirth 1962). Within Louisiana


27

waters, these turtles probably occur all along the coast and may nest on the Chandeleur Islands

(Dundee and Rossman 1989). Population decline has been attributed to heavy fishing pressure

and human nest predation (Dundee and Rossman 1989; Perrine 2003; Spotila 2004). Historically,

green sea turtles were fished off the Louisiana coast, especially the Chandeleur Islands (Rebel

1974). Exploitation and incidental drowning in shrimp trawls has contributed to the decline of

this species and its eventual listing (King 1981). During their first year of life, green sea turtles

are primarily carnivorous, feeding mainly on invertebrates. Green turtles are the only sea turtles

that eat large amounts of plants, feeding in shallow water areas with abundant seagrasses or algae

(Fritts et al. 1983; Spotila 2004). Green sea turtles also feed on invertebrates and carrion

(Dundee and Rossman 1989). The green sea turtle grows to the second largest size of any sea

turtle, with a maximum shell length of 55 inches (140 cm) and a maximum weight of 517 lbs

(235 kg), but most are considerably smaller (Perrine 2003).

The turtles migrate from nesting areas to feeding grounds, which are sometimes several thousand

miles away. Most turtles migrate along the coasts, but some populations are known to migrate

across the ocean from nesting area to feeding grounds. The major nesting beaches are always

found in places where the seawater temperature is greater than 77 ̊F (25 ̊C). As a species that

migrates long distances, these turtles face special problems associated with differing attitudes

toward conservation in different countries. Green turtles are the only sea turtles known to come

ashore for purposes other than nesting. Both immature and adult green sea turtles are known to

bask (Perrine 2003).

In the southeastern United States, green sea turtles are found around the U.S. Virgin Islands,

Puerto Rico, and the continental U.S. from Texas to Massachusetts. The primary nesting sites in

U.S. Atlantic waters are along the east coast of Florida, with additional sites in the U.S. Virgin

Islands and Puerto Rico.

Green sea turtles are also found throughout the North Pacific, ranging as far north as Eliza

Harbor, Admiralty Island, Alaska, and Ucluelet, British Columbia. In the eastern North Pacific,

green sea turtles have been sighted from Baja California to southern Alaska. In the central

Pacific, green sea turtles can be found at most tropical islands. In U.S. Hawaiian waters, green

sea turtles are found around most of the islands in the Hawaiian Archipelago. The primary

nesting site is at French Frigate Shoals.

Female green sea turtles lay one to seven clutches of eggs in a single nesting season with each

clutch contains an average of 110 eggs (Spotila 2004). The number of nests has been estimated

to be between 350 to 2,300 nests annually. Green sea turtles nest at two, three, or four-year

intervals. This nesting activity indicates a population of less than 1,000 females in the breeding

population of Florida and Mexico. It takes longer for a green turtle to reach maturity than any

other sea turtle, typically living 45-59 years (Spotila 2004).

5.7 Loggerhead Sea Turtle

The loggerhead sea turtle (Caretta caretta) was listed as a threatened species on July 28, 1978

(43 FR32800). Critical habitat has been proposed (October 4, 1978 (43 FR 45905); November

29, 1978 (43 FR 55806); and March 19, 1980 (45 FR 17588)) but has not been finalized.

Loggerheads are circumglobal, inhabiting continental shelves, bays, estuaries, and lagoons in

temperate, subtropical, and tropical waters. In the Atlantic, the loggerhead turtle's range extends

from Newfoundland to as far south as Argentina. During the summer, nesting occurs in the lower


28

latitudes. The primary Atlantic nesting sites are along the east coast of Florida, with additional

sites in Georgia, and the Carolinas; some nesting also occurs on the Gulf Coast of Florida. In the

eastern Pacific, loggerheads are reported as far north as Alaska, and as far south as Chile.

Occasional sightings are also reported from the coast of Washington, but most records are of

juveniles off the coast of California. Southern Japan is the only known breeding area in the north

Pacific (NMFS 2010).

The loggerhead sea turtle has continued to decline in Louisiana (USFWS 2010). Perrine (2003)

and Spotila (2004) provide recent summaries of loggerhead sea turtle biology, behavior and

conservation. Loggerheads are capable of living in a variety of environments, such as in brackish

waters of coastal lagoons and river mouths. During the winter, they may remain dormant, buried

in the mud at the bottom of sounds, bays, and estuaries. The major nesting beaches are located in

the southeastern United States, primarily along the Atlantic coast of Florida, North Carolina,

South Carolina, and Georgia. Only minor and solitary nesting has been recorded along the coasts

of the GOM.

The largest of the hard-shell sea turtles, the loggerhead is distributed worldwide in temperate and

tropical bays and open oceans. Loggerheads probably range all along the Louisiana coast;

however, Dundee and Rossman (1989) reported specimens only from Chandeleur Sound,

Barataria Bay, and Cameron Parish. The population decline of loggerheads can be attributed to

egg and nestling predation by mammals and birds (Dundee and Rossman 1989).

Nesting on the Gulf Coast occurs between the months of April and August, with 90 percent of

the nesting effort occurring on the south-central Gulf Coast of Florida (Hildebrand 1981).

Although loggerheads have been documented as nesting on the Chandeleurs in 1962 and Grand

Isle in the 1930s, it is doubtful whether this species currently successfully nests on the Louisiana

coast (Hildebrand 1981, Dundee and Rossman 1989). The loggerhead's diet includes marine

invertebrates such as mollusks, shrimp, crabs, sponges, jellyfish, squid, sea urchins, and basket

stars (Caldwell et al. 1955; Hendrickson 1980; Nelson 1986). Landry (1986) suggested that these

turtles may also feed on discarded by-catch from shrimp trawling. Adult loggerheads feed in

waters less than fifty meters deep, while the primary foraging areas for juveniles appears to be in

estuaries and bays (Nelson 1986; Rabalais and Rabalais 1980).

5.8 Brown Pelican

Although the brown pelican (Pelecanus occidentalis) was removed from the List of Endangered

and Threatened Species on December 17, 2009, brown pelicans and their nests continue to be

protected under the Migratory Bird Treaty Act (USFWS 2010c).

Brown pelicans nest in Louisiana from April through August. They are known to nest on barrier

islands in Lafourche and Terrebonne Parishes. Nesting surveys conducted by LDWF between

2004 and 2008 revealed that Raccoon was the only island with nesting location within the

Project Boundary (LDWF 2004, 2006, 2007, 2008, and 2010). Results of the surveys for

Raccoon Island are presented in Table 5-2.


29

Table 5-2. Estimated Number of Nests/Nesting Pair of Brown Pelicans

Year Raccoon Island

2004 5,400

2005 6,200

2006 3,075

2007 3,850

2008 7,600

In spring and summer, nests are built in mangrove trees or other shrubby vegetation, although

ground nesting may also occur. Brown pelicans feed along the Louisiana coast in shallow

estuarine waters, using sand spits and offshore sand bars as rest and roost areas. Major threats to

this species include chemical pollutants, colony site erosion, disease, and human disturbance

(USFWS 2010c).

5.9 Colonial Nesting Waterbirds

The islands included in the NER host a variety of colonial nesting waterbird species. These

species breed in high densities along the shorelines and barrier islands of Coastal Louisiana. The

benefits of colonial nesting include group defense from predation, increased foraging efficiency,

and maximization of limited breeding sites (Wittenberger and Hunt 1985, Siegel-Causey and

Kharitonv 1990).

Many of these species exhibit both site fidelity and group adherence (Michot et al. 2003). They

tend to concentrate their breeding efforts in relatively few colonies, even to the exclusion of

adjacent, potentially suitable sites (Forbes and Kaiser 1994). Consequently, large populations

are susceptible to stochastic events that could adversely impact their breeding success, and thus

survival. These events include erosion-induced habitat loss, coastal development, sea level rise,

and predation (Jackson et. al 1982, Burger 1984, Visser and Peterson 1994, Goodrich and

Buskirk 1995, Rolland et al. 1998, Erwin et al. 2003).

Colonial nesting waterbirds have been identified as species of special interest within the Project

Boundary by the USFWS (USFWS, 2010a). In 2008, the LDWF conducted a survey of colonial

nesting waterbirds on the Isles Dernieres (LDWF, 2010). The results from the study are

presented in Table 5-3.


30

Table 5-3. Estimated Number of Nests/Nesting Pair of Colonial Nesting Waterbirds

Year Raccoon Island Whiskey

Island

Trinity

Island

Timbalier

Island

American Oystercatcher 2 6 5 NA

Black Skimmer 1,100 535 75 NA

Black-crowned Night Heron 120 0 0 NA

Black-necked Stilt 0 3 0 NA

Brown Pelican 7,600 0 0 NA

Clapper Rail 0 10 10 NA

Great Egret 150 0 0 NA

Green Heron 0 0 5 NA

Gull-billed Tern 30 11 0 NA

Laughing Gull 8,000 0 0 NA

Least Tern 0 70 45 NA

Reddish Egret 20 0 0 NA

Roseate Spoonbill 30 0 0 NA

Royal Tern 10,600 0 0 NA

Sandwich Tern 4,800 0 0 NA

Snowy Egret 80 0 0 NA

Tri-colored Heron 400 0 0 NA

White Ibis 70 0 0 NA

Willet 0 0 12 NA

Wilson’s Plover 30 36 30 NA

NA – Not Available

Results from the survey revealed the presence of colonial nesting birds within the project

boundary, particularly on Raccoon Island. Although Timbalier Island was not surveyed in 2008,

similar surveys conducted in 2006 did not reveal any colonial nesting bird species.

6 ANTICIPATED EFFECTS OF THE PROPOSED PROJECT

6.1 NER Plan

The anticipated effects of the proposed NER plan are discussed in the following section. Impacts

resulting from the one-island first component of construction are discussed in Section 6.2.

6.1.1 Piping Plover

Critical Habitat Impacts

Beneficial impacts to the piping plover and its critical habitat include the restoration of habitat

and prolonged life of barrier islands for the NER plan, as well as creating new barriers or

structures that would function to protect critical habitat. Much of the existing system is sedimentstarved, and the proposed Project would introduce sediment into the system that would be reworked and redistributed through future storm events, thus maintaining and/or enhancing the

features of critical habitat (i.e. sand and mud flats) that are essential to piping plover

conservation. Apart from the terminal groin on Raccoon Island, the project is not expected to

alter the natural long-shore sediment transport mechanisms within the Isles Deneries and

Timbalier Islands. Without the terminal groin, the sediment that moves off of Raccoon Island to

the west is lost to the shoals and buried by the mud stream from the Atchafalaya. Therefore, the

terminal groin on Raccoon Island will not starve other islands in adjacent reaches.


31

In order to quantify the benefits of the project, the predicted critical habitat acres for the “no

action” alternative (i.e. future without project conditions) were compared to that of each island in

the NER plan (i.e. future with project conditions). Critical habitat was assumed to be the

unvegetated portion of the dune, supratidal, and gulfward intertidal habitats. The intertidal

habitats, such as the beaches, mudflats, and sand flats, provide vital foraging grounds for the

plover. Unvegetated dune and supratidal habitats function as suitable roosting and sheltering

areas. The predicted critical habitat acres are provided in Tables 6-1 through 6-4.

Table 6-1. Predicted Critical Habitat Acreages for Raccoon Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY20 TY301 TY31 TY40 TY50

FWOP2 61 61 43 23 10 6 6 0 0

FWP3 61 680 295 348 339 183 276 139 133

Net4 0 619 253 325 329 178 270 139 133

1

Renourishment occurs at TY30

2

FWOP – future without project (i.e. no action)

3

FWP – future with project

4

Net = FWP - FWOP

Table 6-2. Predicted Critical Habitat Acreages for Whiskey Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY201 TY21 TY30 TY401 TY41 TY50

FWOP2 221 220 91 64 47 46 37 0 0 0

FWP3 221 843 236 223 127 615 212 89 464 118

Net4 0 624 146 159 80 569 174 89 464 118

1

Renourishment occurs at TY20 and TY40

2

FWOP – future without projects (i.e. no action)

3

FWP – future with project

4

Net = FWP - FWOP

Table 6-3. Predicted Critical Habitat Acreages for Trinity Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY20 TY251 TY26 TY30 TY40 TY50

FWOP2 158 149 110 60 10 6 6 3 0 0

FWP3 158 583 238 232 154 123 626 277 170 87

Net4 0 434 128 172 145 116 620 274 170 87

1

Renourishment occurs at TY25

2

FWOP – future without projects (i.e. no action)

3

FWP – future with project

4

Net = FWP - FWOP


32

Table 6-4. Predicted Critical Habitat Acreages for Timbalier Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY20 TY301 TY31 TY40 TY50

FWOP2 256 258 187 201 99 30 28 5 0

FWP3 256 2312 983 1152 1006 587 867 381 227

Net4 0 2053 796 952 907 557 839 376 227

1

Renourishment occurs at TY30

2

FWOP – future without project (i.e. no action)

3

FWP – future with project

4

Net = FWP - FWOP

If the NER plan is not constructed and the islands are allowed to erode at their current rate, the

majority of the critical habitat on each of these four islands is expected to disappear by TY40.

As seen in Tables 6-1 through 6-4, the NER plan is expected to substantially increase the amount

of critical habitat on the islands for each target year in the period of analysis. However,

unavoidable short term impacts to the critical habitat would result from the placement of

sediments onto existing beach and dune habitats during construction and renourishment. These

activities would smoother existing populations of benthic prey species. Prey species smothered

by dune and beach creating activities would re-colonize in these areas within two years once

construction activities cease (USFWS, 2010a). The critical habitat values do not account for the

required recovery time of these prey species. For example, there will be approximately 867

acres of critical habitat on Timbalier Island immediately after renourishment (i.e. TY31).

However, the island will not reach optimal conditions for the piping plover until TY33, once the

benthic species have recovered.

Any impacts that would occur to existing designated critical habitat would be temporary, and

would provide for the long-term maintenance and/or enhancement of critical habitat within the

Project Boundary. There would be no permanent impacts to critical habitat that would change the

ecological processes that maintain it. However, because an entire island would be affected during

a construction event, and because adjacent islands may undergo construction within two years or

less, the ability of those islands to provide enough suitable foraging habitat to piping plovers will

likely be affected until all construction is completed (USFWS 2010a). Based on these factors, it

is the Corps’ determination that the NER plan is likely to adversely affect piping plover and its

critical habitat.

Species Impacts

Under optimal conditions, impacts to piping plovers could be avoided by conducting the

proposed activities outside the wintering season. However, construction of the Project is likely

to occur while plovers are present because construction of the NER is anticipated to take 2,480

days. Due to the magnitude of erosion and land-loss rates, delaying the project to the nonwintering season could result is considerable degradation to the island foundation and thus

significant increases in fill volume requirements. Furthermore, delays would be extremely risky

because the existing habitats would be more vulnerable to hurricane forces. Therefore, the risks

associated with delaying the project are not justified based on the temporary nature of the

disturbance.


33

Due to their mobility, piping plovers would be able to avoid areas of temporary disturbance

using the abundance of suitable foraging and roosting areas adjacent to the Project Boundary.

For example, East Island, which is a continuation of Trinity Island, currently supports 272 acres

of critical habitat. East Timbalier Island and Wine Island collectively provide 259 acres of

suitable habitat for piping plover, although the islands have not been technically designated as

critical habitat. These three islands are located within the Isle Deneires and Timbalier Island

Ranges, immediately adjacent to the islands in the NER plan. There is also a considerable

amount of critical habitat near the Project Boundary. For example, West Belle Pass, Elmers

Island, and East Grand Terre are located approximately 15 miles, 25 miles, and 40 miles east of

Timbalier Island, respectively (Figure 6-1). Locust Bayou and the Atchafalaya Delta offer

additional critical habitat west of Raccoon Island (Figure 6-2). Suitable habitat can also be found

at Point au Fer Island and at the numerous pockets and sand and mudflats along Coastal

Louisiana.

Figure 6-1. Piping Plover Critical Habitat West of Raccoon Island


34

Figure 6-2. Piping Plover Critical Habitat East of Timbalier Island

During the Preliminary Engineering and Design (PED) phase, the USACE will assess the

feasibility of staggering the construction of the islands such that only one island is disturbed at

any point in time. Furthermore, the USACE will attempt to adopt an “every other island”

approach to construction. For example, Timbalier Island would be constructed after Whiskey,

followed by Trinity and then Raccoon. This will minimize disturbance to the piping plover

during construction and maintain an abundance of critical habitat within the immediate vicinity

of the disturbed island. By staggering the initial construction of the islands in the NER plan, the

renourishment events would also be staggered. However, constructing the islands in series could

significantly delay the completion of the project and inflate project costs.

The current WRDA 2007 authorization will only support the construction of the first component

of construction (Whiskey Island Plan C). Therefore, this island will likely be built first while the

USACE is seeking additional authorization to construct the other three islands in the NER plan.

The proposed beach and dune components of Whiskey Island will be constructed before the

marsh templates. During marsh construction, the benthic organisms on the beaches would begin

to recover. Raccoon, Trinity, East, and Timbalier Island would remain undisturbed during

sediment placement on Whiskey and thus would provide critical habitat for displaced plovers. If

and when Congress grants additional authorization, the benthic organisms on Whiskey Island

would be in the recovery phase and would likely be able to support displaced plovers during the

construction of the three other islands in the NER plan. If economically feasible, the remaining

three islands would be constructed in series.

Due to the temporary impacts to the critical habitat and the associated benthic communities

during the construction and restoration of the islands, it is the Corps’ determination that the

proposed NER plan is likely to adversely affect piping plover.


35

Oil Spill-related Impacts

The Deepwater Horizon was an ultra-deepwater offshore rig that was conducting exploratory

drilling off the Coast of Louisiana. On April 20, 2010, the drill breached a pocket of highpressure methane gas which ignited and created an explosion on the platform. The explosion and

ensuing fire caused eleven deaths and eventually capsized the rig, creating a massive oil spill in

the Gulf of Mexico. The sunken rig is located approximately 125 miles southeast of Timbalier

Island.

Since the spill, oil has been found on the gulfward shorelines of each island in the Isle Dernieres

and Timbalier Island reaches. The quantity of oil washed on to the shorelines was approximated

using Shoreline Cleanup Assessment Technique (SCAT) data (NOAA, 2010). Oil impacts were

categorized as heavy, moderate, light, very light, tar balls, and no oil observed. The oil impacts

for the four islands in the NER plan are presented in figures 6-3 through 6-6.

 	
  	


Figure 6-3. Deepwater Horizon Oil Spill Impact on Raccoon Island (NOAA, 2010)


36


 	
 
 	


Figure 6-4. Deepwater Horizon Oil Spill Impact on Whiskey Island (NOAA, 2010)



 	
 

 	


Figure 6-5. Deepwater Horizon Oil Spill Impact on Trinity Island (NOAA, 2010)


37


	
 
	
 	


Figure 6-6. Deepwater Horizon Oil Spill Impact on Timbalier Island (NOAA, 2010)

Oil has also been found on Atchafalaya, Locust Bayou, West Belle Pass, Elmer’s Island, and

East Grand Terre, all of which support critical habitat adjacent to the Project Boundary.

Potential piping plover impacts associated with the oil spill primarily consist of a reduction in

available food supply. Piping plovers primarily feed on benthic organisms found in intertidal

beaches, mudflats, sand flats, algal flats, and washover passes. The effects of oil on the health of

benthic communities can be both acute and chronic in nature. According to the USFWS, oil can

be directly toxic to these organisms or impact them through physical smothering, altering

metabolic and feeding rates, and altering shell formation. Intertidal benthic communities may be

particularly vulnerable when oil becomes highly concentrated in narrow bands along the

shoreline (USFWS, 2004). Barnacles and other sessile species are vulnerable to smothering by

heavy oils while the physiological effects of the hydrocarbons can considerably reduce the

mobility of the more mobile species (University of Delaware, 2010). Additionally, sediments

can become reservoirs for the spilled petroleum. Some benthic invertebrates can survive the

initial exposure, but may accumulate high levels of contaminants in their bodies that can be

passed on to predators (USFWS, 2004).

The magnitude of the impacts is also a function of the characteristics of oil spilled. For example,

a study conducted on the Amoco Cadiz spill in 1978 revealed that “light oil” resulted in

considerable detrimental impacts to the benthic communities. However, a separate study

revealed that the benthic organisms were contaminated, but were not adversely impact, from a

spill of heavy crude (University of Delaware, 2010).

In 2003, Donlan et al. assessed the impacts of the North Cape oil spill on communities of piping

plover in Rhode Island. The study first examined the abundance of prey species on Moonstone

Beach (the oiled island) and compared it to that of an adjacent, un-oiled beach (Goosewing).

Although the abundance of benthic organisms was not significantly different between the two

beaches, the species composition was considerably dissimilar. For example, only two


38

Amphilporeia were found in the sampling station on Moonstone, compared to 456 at Goosewing.

This reinforced the common belief that amphipods are the first group of organisms to disappear

and one of the last to recolonize once exposed to oil. Based on this information, the authors

concluded that the piping plovers’ food supply may have been reduced because of the oil spill.

The authors also noted a decline in the number of fledgings produced per nesting pair between

1995 and 1996 (the year of the spill). This reduction was attributed to the lack of available prey

species in the intertidal zone, which caused plovers to travel longer distances and expend more

energy when feeding (Donlan et al., 2003).

Between 1990 and 1995, Jewett et al. assessed the impacts of the Exxon Valdez oil spill on the

benthic communities in Prince Williams Sound, Alaska. The metrics of the study included

concentrations of hydrocarbons and benthic community composition, diversity, biomass, and

abundance. These metrics were compared between a number of reference sites and oiled sites.

The comparison was conducted in 1990 (approximately 16 months after the spill), 1991, 1993,

and 1995.

According to the authors, the “total abundance and biomass of epifauna were generally higher at

oiled sites, primarily because of higher densities of epifaunal bivalves. Otherwise, there were few

consistent community-wide responses to oiling in diversity, richness, total abundance, total

biomass, or the abundances of major taxonomic groups (e.g. polychaetes or bivalves).” The lack

of a stronger community-wide response was attributed to the varying sensitivities of benthic

organisms. For example, oil-sensitive amphipods such as Isaeidaes and Phoxocephalidaes were

found in lower concentrations at the oiled sites. These impacts were evident throughout the

duration of the study (i.e. 6 years after the spill). However, stress-tolerant and opportunistic

organisms such as polychaetes were found in higher concentrations at the oiled sites due to

organic enrichment. The study also revealed that hydrocarbon concentrations in the sediment

were high (up to 15,300 ng/g) in eel grass beds immediately adjacent to the oiled shorelines, but

sharply declined after 1990 (Jewett et all, 1999). Although the benthic organisms and habitat

types within Prince Williams Sound vary from that of the Project Area (eelgrass beds versus

sand beds and mud flats), the study does provide an indication of the resiliency and recovery

rates of benthic communities as a whole. Furthermore, the results of the study indicate that the

species composition of the benthic communities is expected to shift as a result of the Deepwater

Horizon oil spill. For example, amphipods, which are favored by the piping plover, are expected

to decrease in number while other less-favorable species may increase.

As previously stated, the NER plan will likely impact benthic communities by smothering them

during fill placement. In the short term, this could further stress the oil-impacted benthic

organisms that are currently on the island. However, sediment used for fill placement would be

tested to ensure that it is free of oil before it is placed on the island. Placement of clean sediment

on the islands could potentially improve the quality of the benthic habitat by diluting

concentrations of oil in the island’s intertidal zone. This could, in turn, speed up the recovery

time of the oil-impacted benthic communities.

6.1.2 West Indian Manatee

Manatee occurrences have been regularly reported in the canals and coastline of Louisiana.

Collision with boats and barges is one of the primary anthropogenic causes of manatee

mortalities. To avoid any impacts to the West Indian Manatee, all contract personnel associated

with the Project will be informed of the potential presence of manatees and the need to avoid


39

collisions with manatees, which are protected under the Marine Mammal Protection Act of 1972

and the Endangered Species Act of 1973. All construction personnel will be required to monitor

all water-related activities for the presence of manatee(s). Temporary signs will be posted prior

to and during all construction/dredging activities to remind personnel to be observant for

manatees during active construction/dredging operations or within vessel movement zones (i.e.,

work area), and at least one sign will be placed where it is visible to the vessel operator.

Siltation barriers, if used by the contractor, will be made of material in which manatees could not

become entangled, and will be properly secured per technical specifications provided by the

manufacture. If a manatee is sighted within 100 yards of the active work zone, special operating

conditions will be implemented, including:

•No operation of moving equipment within 50 feet of a manatee

•All vessels will operate at no wake/idle speeds within 100 yards of the work area

• Siltation barriers, if used, will be monitored and re-secured as necessary

Once the manatee has left the 100-yard buffer zone around the work area on its own accord,

special operating conditions are no longer necessary, but careful observations will resume. Care

will also be taken to avoid entrapment of individuals if any structure is to be installed that could

be a barrier or impediment to manatee movement.

By implementing the above-mentioned manatee monitoring and avoidance program, it is the

Corps’ determination that the proposed NER plan “may affect, but will not likely adversely

affect” the endangered West Indian Manatee.

6.1.3 Sea Turtles

Based on professional experience and related CWPPRA project construction methods, it is

anticipated that the contractor will use a hydraulic cutterhead dredge and booster pump(s) to

excavate sediment from the available offshore borrow area(s) and directly transport it via a

submerged sediment pipeline to the islands. Environmental laws protecting sea turtles could

possibly require the cessation of work for a limited time if the allowable number of sea turtles

mortalities is exceeded during dredging. However, turtles are typically able to avoid cutterhead

dredge intakes because the dredges move along the seabed at such a slow speed. Sediment used

to construct the containment dikes will be dredged from existing material inside the marsh

creation area rather than from offshore borrow areas. Therefore, dredging operations associated

with the containment dikes are not expected to adversely impact sea turtles.

In summary, it is the Corps’ determination that the borrow area dredging operations “may affect,

but will not likely adversely affect” populations of sea turtles in the Project Boundary. Impacts

associated with the actual placement of fill on the islands are discussed below for each species of

threatened/endangered sea turtles identified by USFWS.

Green Sea Turtle

Due to the lack of extensive seagrass beds throughout much of coastal Louisiana, and the low

incidence of sightings and strandings, it is the Corps’ determination that placement of fill on four

islands in the NER is expected to have “no effect” on the green sea turtle population.


40

Hawksbill Sea Turtle

It is the Corps’ determination that placement of fill on the four islands in the NER will have “no

effect” on hawksbill populations due to its rarity along the Louisiana coast.

Kemp’s Ridley Sea Turtle

The proposed NER plan would provide more suitable inshore habitat for foraging. This habitat

type is characterized by lower salinity and high turbidity and organic content, where shrimp and

blue crabs are abundant Therefore, it is the Corps’ determination that placement of fill on the

four islands in the NER plan “may affect, but will not likely adversely affect” populations of

Kemp’s ridley sea turtles.

Leatherback Sea Turtle

This pelagic species typically occupies oceanic waters of more than 160 feet (50 m) in depth.

Therefore, it is the Corps’ determination that placement of fill on the four islands in the NER

plan is expected to have “no effect” on Leatherback sea turtle populations.

Loggerhead Sea Turtle

Nesting loggerhead sea turtles have historically used barrier islands; however, it is doubtful that

loggerhead sea turtles nest anywhere on the Louisiana coast. The restoration of Raccoon,

Whiskey, Trinity, and Timbalier Island may or may not provide suitable nesting habitat, but

suitable nesting habitat is nearly nonexistent due to the current degraded state of these islands.

The NER plan would not negatively affect loggerheads and could potentially provide some

benefit to the species by restoring nesting habitat. Therefore, it is the Corps’ determination that

placement of fill on the four islands in the NER plan “may affect, but will not likely adversely

affect” populations of Loggerhead sea turtles.

6.1.4 Brown Pelican

Suitable brown pelican feeding and/or nesting habitat occurs along the barrier islands, sand spits,

and mud lumps throughout the Project Boundary. Pelicans and their nest sites may be impacted

by barrier island restoration activities or noise disturbance from work activities. Unavoidable

short term impacts to brown pelicans include placement of sediment within foraging or roosting

areas in or near the Project Boundary. Additional impacts could result from equipment noise and

increased human activity on the islands. As previously stated, it is not feasible to delay project

construction until after the nesting season. However, there is an abundance of suitable habitat

available nearby should the birds be temporarily displaced. Furthermore, the sequencing of

construction will allow the pelicans to relocate to adjacent suitable habitat within the Project

Boundary (Section 6.3). Once construction activities are complete, any birds disturbed by the

activities are expected to return to the area.

The proposed barrier island restoration activities for the four islands in the NER are likely to

create new nesting habitat and prolong the life of existing suitable nesting habitat. In addition,

restoration of barrier habitat and salt marsh would provide nursery and grow-out areas for the

aquatic life upon which pelicans feed (USFWS 2010c). Therefore, it is the Corps’ determination

that the proposed NER plan “may affect, but will not likely adversely affect” the brown pelican.


41

6.1.5 Colonial Nesting Birds

The bird count survey conducted by LDWF in 2008 revealed the presence of various species of

colonial nesting waterbirds on Raccoon, Whiskey, and Trinity Islands (Section 5.9). As with the

brown pelican, unavoidable short term impacts would include placement of sediment within

foraging or roosting areas in or near the Project Boundary. However, the proposed barrier island

restoration activities for the four islands in the NER are likely to create new nesting habitat and

prolong the life of existing suitable nesting habitat. Furthermore, there is abundant suitable

habitat in the vicinity of islands that can host temporally displaced colonial nesting birds during

construction. Sequencing of construction will also help to minimize impacts to the nesting birds.

Therefore, it is the Corps’ determination that the proposed NER plan “may affect, but will not

likely adversely affect” colonial nesting birds.

6.2 First Component of Construction

The first component of construction, which consists of Whiskey Island Plan C, is a subset of the

NER plan and is therefore expected to experience similar impacts. However, since only one

island is being restored rather than four, construction related impacts are not expected to be as

severe. The following sections describe the impacts of the first component of construction on

threatened and endangered species, as well as the species of special interest.

6.2.1 Piping Plover

Critical Habitat Impacts

As with the NER Plan, beneficial impacts to the piping plover and its critical habitat include the

restoration of habitat and prolonged life of Whiskey Island, as well as creating new barriers or

structures that would function to protect critical habitat. The implementation of first component

of construction would also increase sediment available to Raccoon Island because the long shore

sediment movement is westward. The predicted critical habitat acres on Whiskey Island are

provided in Table 6-5.

Table 6-5. Predicted Critical Habitat Acreages for Whiskey Island

Critical Habitat (acres)

TY0 TY1 TY5 TY10 TY201 TY21 TY30 TY401 TY41 TY50

FWOP2 221 220 91 64 47 46 37 0 0 0

FWP3 221 843 236 223 127 615 212 89 464 118

Net4 0 624 146 159 80 569 174 89 464 118

1

Renourishment occurs at TY20 and TY40

2

FWOP – future without projects (i.e. no action)

3

FWP – future with project

4

Net = FWP - FWOP

Whiskey Island is expected to disappear considerably sooner than the other islands in the Isles

Dernieres and Timbalier Island Ranges. The island currently lacks dune habitat. If no action is

taken on the island, supratidal and intertidal habitat is expected to disappear by TY17 and TY31,

respectively (compared to TY33 and TY40 for Trinity Island).


42

As seen in Table 6-5, the first component of construction is expected to substantially increase

the amount of critical habitat on Whiskey Island for each target year in the period of analysis.

However, as with the NER plan, unavoidable short term impacts to the critical habitat would

result from the placement of sediments onto existing beach and dune habitats during

construction and renourishment. These activities would smother existing populations of benthic

prey species. However, any impacts that would occur to existing designated critical habitat

would be temporary, and would provide for the long-term maintenance and/or enhancement of

critical habitat within the Project Boundary. There would be no permanent impacts to critical

habitat that would change the ecological processes that maintain it.

However, because the entire island would be affected during a construction event, and because

adjacent islands may undergo construction within two years or less, the ability of those islands to

provide enough suitable foraging habitat to piping plovers will likely be affected until all

construction is completed (USFWS 2010a). Based on these factors, it is the Corps’ determination

that the construction of the first component of construction is likely to adversely affect piping

plover and its critical habitat.

Species Impacts

As with the NER plan, construction of the Project is likely to occur while plovers are present.

However, due to their mobility, piping plovers would be able to avoid areas of temporary

disturbance using the abundance of suitable foraging and roosting areas adjacent to the Project

Boundary. For example, Raccoon, Trinity, East, and Timbalier Islands currently support a total

of 1318 acres of critical habitat. East Timbalier Island and Wine Island collectively provide 259

acres of suitable habitat for piping plover, although the islands have not been technically

designated as critical habitat. These six islands are located within the immediate vicinity of

Whiskey Island.

However, due to the temporary impacts to the critical habitat and the associated benthic

communities during the construction and restoration of Whiskey Island, it is the Corps’

determination that the construction of the first component of construction is likely to adversely

affect piping plover.

Oil Spill-related Impacts

The oil spill-related impacts related to the first component of construction are similar to those

discussed for the NER plan (see Section 6.1.1).

6.2.2 West Indian Manatee

The potential impacts of the first component of construction on the West Indian Manatee are

similar to that of the NER plan. By implementing the manatee monitoring and avoidance

program discussed in Section 6.1.2, it is the Corps’ determination that the proposed Project “may

affect, but will not likely adversely affect” the endangered West Indian Manatee.

6.2.3 Sea Turtles

The potential dredging impacts of the first component of construction on Sea Turtles are similar

to that of the NER plan. However, since the first component of construction is a single island, it

will require much less dredged material then the NER plan, thus reducing the probability of turtle

impacts. As with the NER plan, a cutterhead dredge will be used in the initial construction and

restoration of the island. It is the Corps’ determination that the borrow area dredging operations


43

“may affect, but will not likely adversely affect” populations of sea turtles in the Project

Boundary. Impacts associated with the actual placement of fill on Whiskey Island are discussed

below for each species of threatened/endangered sea turtles identified by USFWS.

Green Sea Turtle

Due to the lack of extensive seagrass beds throughout much of coastal Louisiana, and the low

incidence of sightings and strandings, it is the Corps’ determination that placement of fill on

Whiskey Island is expected to have “no effect” on the green sea turtle population.

Hawksbill Sea Turtle

It is the Corps’ determination that placement of fill on Whiskey Island will have “no effect” on

hawksbill populations due to its rarity along the Louisiana coast.

Kemp’s Ridley Sea Turtle

The proposed first component of construction would provide more suitable inshore habitat for

foraging. This habitat type is characterized by lower salinity and high turbidity and organic

content, where shrimp and blue crabs are abundant Therefore, it is the Corps’ determination that

placement of fill on Whiskey Island “may affect, but will not likely adversely affect” populations

of Kemp’s ridley sea turtles.

Leatherback Sea Turtle

This pelagic species typically occupies oceanic waters of more than 160 feet (50 m) in depth.

Therefore, it is the Corps’ determination that placement of fill on Whiskey Island is expected to

have “no effect” on Leatherback sea turtle populations.

Loggerhead Sea Turtle

Nesting loggerhead sea turtles have historically used barrier islands; however, it is doubtful that

loggerhead sea turtles nest anywhere on the Louisiana coast. The restoration of Whiskey Island

may or may not provide suitable nesting habitat, but suitable nesting habitat is nearly nonexistent

due to the current degraded state of these islands. The first component of construction plan

would not negatively affect loggerheads and could potentially provide some benefit to the

species by restoring nesting habitat. Therefore, it is the Corps’ determination that placement of

fill on Whiskey Island “may affect, but will not likely adversely affect” populations of

Loggerhead sea turtles.

6.2.4 Brown Pelican

The proposed barrier island restoration activities for the first component of construction are

likely to create new nesting habitat and prolong the life of existing suitable nesting habitat. In

addition, restoration of barrier habitat and salt marsh would provide nursery and grow-out areas

for the aquatic life upon which pelicans feed (USFWS 2010c). Therefore, it is the Corps’

determination that construction of the first component of construction “may affect, but will not

likely adversely affect” the brown pelican.

6.2.5 Colonial Nesting Birds

As with the brown pelican, unavoidable short term impacts would include placement of sediment

within foraging or roosting areas in or near the Project Boundary. However, the proposed barrier

island restoration activities for the first component of construction is likely to create new nesting


44

habitat and prolong the life of existing suitable nesting habitat. Furthermore, there is abundant

suitable habitat in the vicinity of islands that can host temporally displaced colonial nesting birds

during construction. Therefore, it is the Corps’ determination that construction of the first

component of construction “may affect, but will not likely adversely affect” colonial nesting

birds.

6.2.6 Brown Pelican and Colonial Nesting Bird Protection Plan

Throughout PED, consultation will continue with the LDWF, USFWS, and NMFS on detailed

contract specifications to avoid and minimize potential impacts to the brown pelican and colonial

nesting waterbirds. The total construction duration of the NER is 2,480 days, not including

mobilization and demobilization.

Proactive measures will be taken to prevent brown pelicans and colonial nesting waterbirds from

nesting within the Study Area prior to and during construction. These measures may include

deterrents such as propane cannons, predator decoys, or other approved bird repellant devices.

These repellent devices will be placed in designated areas within the Study Area prior to the

nesting periods. Nesting periods are April 2 through September 15 for gulls terns, and/or black

skimmers; February 16 through August 31 for nesting wading birds (i.e., herons, egrets, nightherons, ibis, and roseate spoonbills), anhingas, and/or cormorants; and April 1 through

September 14 for brown pelicans. The contractor will coordinate closely with the LDWF,

USFWS, and NMFS on the timing and placement of the deterrent devices. The USACE

understands the importance of preventing nesting activities within the Study Area that is under

constructions as there is no provision for “incidental take” in the Migratory Bird Treaty Act of

1918

Prior to any work, qualified personnel will conduct surveys in all potential nesting bird habitats

within the Study boundaries that may be impacted by construction or preconstruction activities.

These surveys will be conducted for both brown pelicans and colonial nesting waterbirds. Data

collection protocols will be established through close coordination with the LDWF, USFWS, and

NMFS.

•Nesting periods are April 2 through September 15 for gulls terns, and/or black skimmers;

February 16 through August 31 for nesting wading birds (i.e., herons, egrets, night-herons,

ibis, and roseate spoonbills), anhingas, and/or cormorants; and April 1 through September

14 for brown pelicans.

• Nesting season surveys shall be conducted in all potential nesting bird habitats within the

Study boundaries that may be impacted by construction or preconstruction activities during

the nesting season. Portions of the Study area in which there is no potential for projectrelated activity during the nesting season may be excluded.

• Surveys for detecting new nesting activity will be completed on a daily basis prior to

movement of equipment, operation of vehicles, or other activities that could potentially

disrupt nesting behavior or cause harm to the birds their eggs or young.


45

• Surveys should be conducted by walking the length of the Study area and visually inspecting,

using binoculars or spotting scope, for the presence of shorebirds exhibiting breeding

behavior. If an ATV or other vehicle is needed to cover large Study areas, the vehicle must

be operated at a speed of <6 mph, shall be run at or below the high tide line, and the Bird

Monitor will stop at no greater than 200-meter intervals to visually inspect for nesting

activity.

• Daily summaries of shorebird/brown pelican abundance, location of the birds and their

activity (e.g., foraging, resting, nesting, courtship behavior), and summaries of any nests

observed including the number of eggs and fledglings, shall be provided on the next business

day on an approved report form.

• The Bird Monitor shall communicate the results of their survey to the contractor daily.

• If breeding is confirmed by the presence of a scrape, eggs, or young, the Bird Monitor will

immediately notify the appropriate personnel at the LDWF and USFWS.

If nesting occurs during construction within the Study area, the contractor shall establish a 650-ft

buffer zone around colonies containing nesting gulls, terns, and/or black skimmers; a 1,000-ft

buffer around colonies of nesting wading birds (i.e., herons, egrets, night-herons, ibis, and

roseate spoonbills), anhingas, and/or cormorants; and a 2,000-ft buffer around nesting colonies

of brown pelicans.

• The designated buffer zones shall be posted with clearly marked signs around the perimeter.

These markings shall be maintained until nesting is completed or terminated. In the case of

solitary nesters, nesting is not considered to be completed until all chicks have fledged.

• No construction activities, movement of vehicles, or stockpiling of equipment shall be

allowed within the buffer area unless authorized by LDWF, USFWS, and NMFS.

• LDWF/USFWS/NMFS-approved travel corridors shall be designated and marked outside the

buffer areas. Heavy equipment, vehicles, and pedestrians may transit past nesting areas in

these corridors. However, other activities such as stopping or turning shall be prohibited

within the designated travel corridors adjacent to the nesting site.

• Where such a travel corridor must be established within the Study Area, it shall avoid critical

areas for shorebirds (known nesting sites, designated critical wildlife habitat, and designated

critical piping plover habitat) as much as possible, and be marked with signs clearly

delineating the travel corridor from the shorebird buffer areas described above.

If shorebird or pelican nesting occurs within the Study Area, a bulletin board will be placed and

maintained in the construction area with the location map of the construction site showing the

bird nesting areas and a warning, clearly visible, stating the “bird nesting areas are protected by

the Federal Migratory Bird Treaty Act.”


46

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U.S. Environmental Protection Agency, 2008. “Biological Assessment – Potential Impacts of

the Proposed Whiskey Island Back Barrier Marsh Creation Projects (TE-50) on the Threatened

Piping Plover (Charadrius melodus) and other Relevant Protected Species”. Submitted to the

USFWS.

U.S. Fish and Wildlife Service, 1996. Piping Plover (Charadrius melodus), Atlantic Coast

Population, Revised Recovery Plan. Hadley, Massachusetts.

U.S. Fish and Wildlife Services, 2000. “All About Piping Plovers.” Accessed May 2010 from

USFWS website: http://www.fws.gov/plover/facts.html.

U.S. Fish and Wildlife Services, 2001. “50 CFR Part 17 - Endangered and Threatened Wildlife

and Plans; Final Determination of Critical Habitat for Wintering Piping Plovers; Final Rule”.

Federal Register, Rules and Regulations, pp 36037-36086.


50

U.S. Fish and Wildlife Services, 2004. “Effects of Oil Spills on Wildlife and Habitat – Alaska

Region.” Accessed August 2010 from the USFWS website:

http://www.fws.gov/home/dhoilspill/pdfs/DHJICFWSOilImpactsWildlifeFactSheet.pdf

U.S. Fish and Wildlife Services, 2010a. Unpublished. Letter to Colonel Alvin Lee, USACE,

District Commander. New Orleans District, Louisiana.

U.S. Fish and Wildlife Services, 2010b. Endangered Species Program. Accessed May 2010

from USFWS website: http://www.fws.gov/endangered/

U.S. Fish and Wildlife Services, 2010c. “Draft Fish and Wildlife Coordination Act Report –

Louisiana Coastal Area (LCA) Terrebonne Basin Barrier Shoreline Restoration, Terrebonne and

Lafourche Parishes, Louisiana.” Unpublished. USFWS Ecological Services, April 2010.

U.S. Fish and Wildlife Services, Endangered Species Program, Accessed May 2010 from

USFWS website: http://www.fws.gov/endangered/

Viosa, P., 1961. “Turtles, Tame and Truculent.” Louisiana Conservationist. 13:5-8.

Visser, J., and G. Peterson, 1994. “Breeding Populations and Colony Site Dynamics of Seabirds

Nesting in Louisiana.” Colonial Waterbirds 17:146-152.

Wilcox, L., 1959. “A Twenty Year Banding Study of the Piping Plover.” The Auk 76:129-152

Wittenberger, J., and G. Hunt, 1985. “The Adaptive Significance of Coloniality in Birds.” Avian

Biology Vol. 8, pp. 1–78. Academic Press, New York.

Zwinenberg, A.J, 1977. “Kemp's Ridley, Undoubtedly the Most Endangered Marine Turtle

Today (with notes on the current status of Lepidochelys olivacea).” Bull. Maryland

Herpetological Society. 13:170-192.


TERREBONNE BASIN BARRIER

SHORELINE RESTORATION

APPENDIX A

BIOLOGICAL ASSESSMENT

ANNEX A1

USFWS LETTERS







TERREBONNE BASIN BARRIER

SHORELINE RESTORATION

APPENDIX A

BIOLOGICAL ASSESSMENT

ANNEX A2

USFWS BIOLOGICAL OPINION


Louisiana Coastal Area

Terrebonne Basin Barrier Shoreline Restoration Project

Terrebonne Parish, Louisiana

43440-2010-F-2769

Final Biological Opinion

September 23, 2010

Prepared by:

U.S. Fish and Wildlife Service

646 Cajundome Boulevard, Suite 400

Lafayette, LA


TBBSR biological opinion |Page i

TABLE OF CONTENTS

Consultation History..2

BIOLOGICAL OPINION.....2

DESCRIPTION OF THE PROPOSED ACTION...2

Action area.........5

STATUS OF THE SPECIES/CRITICAL HABITAT5

Species/critical habitat description5

Life history7

Population dynamics...11

Status and distribution.14

Threats to piping plovers/critical habitat...18

Analysis of the species/critical habitat likely to be affected...35

ENVIRONMENTAL BASELINE35

Status of the species within the action area.36

Factors affecting species environment within the action area.38

EFFECTS OF THE ACTION...39

Factors to be considered..40

Analysis for the effects of the action...42

Species response to the proposed action.43

CUMULATIVE EFFECTS...44

CONCLUSION...45

INCIDENTAL TAKE STATEMENT46

AMOUNT OR EXTENT OF TAKE ANTICIPATED.46

EFFECT OF THE TAKE..47

REASONABLE AND PRUDENT MEASURES.47

TERMS AND CONDITIONS...48

COORDINATION OF INCIDENTAL TAKE STATEMENT WITH OTHER LAWS,

REGULATIONS, AND POLICIES50

Migratory Bird Treaty Act...50

CONSERVATION RECOMMENDATIONS50

REINITIATION NOTICE...51

LITERATURE CITED52

APPENDIX A: Figures.A-1

APPENDIX B: Non-breeding Piping Plover Survey Guidelines..B-1

APPENDIX C: Standard Conditions for In-water Work in the Presence of Manatees.C-1

APPENDIX D: Louisiana Guidelines for Minimizing Disturbance to Colonial Nesting Birds...D-1


TBBSR biological opinion |Page ii

LIST OF TABLES

Table 1. Species and critical habitat evaluated for effects from the proposed action but not discussed

further in this biological opinion......1

Table 2. The number of adult piping plovers and breeding pairs reported in the U.S. Northern Great

Plains by the IPPC efforts...11

Table 3. Results of the 1991, 1996, 2001, and 2006 International Piping Plover Winter

Censuses..15

Table 4. Summary of the extent of nourished beaches in piping plover wintering and migrating

habitat within the conterminous U.S...20

Table 5. Visually estimated numbers of navigable mainland and barrier island inlets and hardened

inlets by state...22

Table 6. Summary of predator control programs that may benefit piping plovers on winter and

migration grounds...26

Table 7. Percent of known piping plover winter and migration habitat locations, by state, where

various types of anthropogenic disturbance have been reported28

Table 8. Military bases that occur within the wintering/migration range of piping plovers and contain

piping plover habitat...29

Table 9. Number of sites surveyed during the 2006 winter IPPC with hardened or developed

structures adjacent to the shoreline.33

Table 10. CWPPRA projects that have been constructed on barrier islands within the Terrebonne

Basin.......................................................................................36

Table 11. Piping plover numbers from sporadic survey results within the action area......37

Table 12. Existing critical habitat acreages within the project footprint for each island of the NER Plan

as estimated from 2008 aerial photography....38

Table 13. Results of the SCAT reports for the Deepwater Horizon Mississippi Canyon Well #252 oil

spill and follow-up cleanup activities on Isles Dernieres and Timbalier Island.39

Table 14. Piping plover numbers from winter surveys within the Atchafalaya River Delta.44

Table 15. How the incidental take will be monitored if the specific number of individuals cannot be

determined...47


TBBSR biological opinion |Page iii

LIST OF FIGURES

Figure 1. The proposed National Ecosystem Restoration Plan would encompass the Isles Dernieres

Barrier Islands and Timbalier Island in Terrebonne Parish, Louisiana....A-1

Figure 2. The proposed Raccoon Island Plan E with Terminal Groin would encompass all of Raccoon

Island except for a portion of the western sand spit.A-2

Figure 3. The proposed Whiskey Island Plan C would encompass only portions of Whiskey Island in

order to avoid a previous marsh creation area (TE-50) and existing mangrove habitat ..A-3

Figure 4. The Trinity Island Plan C would encompass most of Trinity Island while avoiding New Cut

and East Island .A-4

Figure 5. The Timbalier Island Plan E would encompass all of Timbalier Island ..A-5

Figure 6. Distribution and range of piping plovers..A-6

Figure 7. Breeding population distribution in wintering/migration range...A-7

Figure 8. Approximate extent of critical habitat that currently exists on Raccoon, Whiskey, Trinity,

and Timbalier Islands .................................................................A-8


TBBSR biological opinion |Page iv

Acronyms

Act Endangered Species Act

BA Biological Assessment

BO Biological Opinion

CFR Code of Federal Regulations

Corps U.S. Army Corps of Engineers

CWPPRA Coastal Wetlands Planning, Protection, and Restoration Act

DPS Distinct Population Segment

EPA Environmental Protection Agency

FR Federal Register

GPS Global Positioning System

IPPC International Piping Plover Census

LCA Louisiana Coastal Area

LDNR Louisiana Department of Natural Resources

LDWF Louisiana Department of Wildlife and Fisheries

MBTA Migratory Bird Treaty Act

MLLW Mean Low Low Water

NAVD North American Vertical Datum

NER National Ecosystem Restoration

NMFS National Marine Fisheries Service

NPS National Park Service

ORV Off-road Vehicle

PCB Polychlorinated Biphenol

PCE Primary Constituent Element

RPMs Reasonable and Prudent Measures

SCAT Shoreline Cleanup Assessment Team

Service U.S. Fish and Wildlife Service

SEIS Supplemental Environmental Impact Statement

TBBSR Terrebonne Basin Barrier Shoreline Restoration

TSP Tentatively Selected Plan

TY Target Year

U.S. United States

USC United States Code

USCG U.S. Coast Guard

USDA U.S. Department of Agriculture

USFS U.S. Forest Service


United States Department of the Interior

FISH AND WILDLIFE SERVICE

646 Cajundome Blvd.

Suite 400

Lafayette, Louisiana 70506

September 23, 2010

Colonel Edward R. Fleming

District Commander

U.S. Army Corps of Engineers

Post Office Box 60267

New Orleans, Louisiana 70160-0267

Dear Colonel Fleming:

This document transmits the U.S. Fish and Wildlife Services (Service) biological opinion based on

our review of the U.S. Army Corps of Engineers (Corps) proposed Louisiana Coastal Area (LCA) 

Terrebonne Basin Barrier Shoreline Restoration (TBBSR) project that would be located in Terrebonne

Parish, Louisiana, and its effects on the threatened piping plover (Charadrius melodus) and its

designated critical habitat, in accordance with section 7 of the Endangered Species Act (Act) of 1973,

as amended (16 United States Code [U.S.C.] 1531 et seq.). Your August 9, 2010, request for formal

consultation was received via electronic mail on that same date.

This biological opinion is based on information provided in the Corps August 9, 2010, biological

assessment (BA); the Corps June 1, 2010, Draft Supplemental Environmental Impact Statement

(SEIS); meetings; telephone conversations; electronic mails; field investigations; and other sources of

information. A complete administrative record of this consultation (Service Log No. 43440-2010-F2769) is on file at the Services Lafayette, Louisiana, Field Office.

The Service concurs with the Corps determination that the proposed project is not likely to adversely

affect the endangered West Indian manatee (Trichechus manatus) because: (1) the project area does

not contain suitable foraging habitat for that species; and (2) the Corps would implement, as part of the

project construction plan, standard conditions for in-water work in the presence of manatees (Appendix

C). Federally listed sea turtles (i.e., Kemps ridley, Hawksbill, Loggerhead, Leatherback, and Green

sea turtles) are not currently known to nest in Louisiana. It is our understanding that the Corps has

conducted a separate consultation with the National Marine Fisheries Service (NMFS) regarding

project-related effects to sea turtles offshore. Accordingly, none of the species mentioned in this

paragraph will be discussed further in this biological opinion.

Table 1. Species and critical habitat evaluated for effects from the proposed action but not

discussed further in this biological opinion.

Species or Critical

Habitat Present in Action Area Present in Action Area but NotLikely to Adversely Affect

West Indian manatee Yes Yes


TBBSR biological opinion| Page 2

Consultation History

On January 21, 2009, the Service provided a list of federally threatened and endangered species to the

Corps in response to their Notice of Intent to prepare a SEIS.

On March 4, 2010, the Service provided an updated list of federally threatened and endangered species

to the Corps. That letter included species-specific recommendations for avoiding and/or minimizing

project-related impacts.

In May 2010, the Service provided a draft Fish and Wildlife Coordination Act Report to the Corps

regarding project-related effects to Service trust resources and our recommendations for avoiding

and/or minimizing impacts. That report also included species-specific recommendations for avoiding

and/or minimizing project-related impacts to federally listed species.

On July 19, 2010, the Service provided comments to the Corps on the Draft SEIS and their June 17,

2010, biological assessment (Appendix A of the Draft SEIS). The Service did not concur with the

Corps determination that the proposed action was not likely to adversely affect the piping plover or its

critical habitat and recommended that the Corps initiate formal consultation.

On July 23, 2010, the Service requested additional information from the Corps regarding their June 17,

2010, BA. On August 9, 2010, the Corps provided the Service with a revised BA which contained the

information required to complete formal consultation and requested initiation of formal consultation.

On August 12, 2010, the Service provided confirmation to the Corps that all information had been

received and that a biological opinion would be issued no later than December 22, 2010.

BIOLOGICAL OPINION

DESCRIPTION OF THE PROPOSED ACTION

According to the BA (Corps 2010), the National Ecosystem Restoration (NER) plan (Figure 1) consists

of Raccoon Island Plan E with a terminal groin, Whiskey Island Plan C, Trinity Island Plan C, and

Timbalier Island Plan E. After construction is complete (i.e., Target Year 1 (TY1)), the NER plan

would result in an additional 3,283 acres of habitat (dune, intertidal, and supratidal) on the existing

island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing the total size of the

islands to 5,840 acres. This includes approximately 472 acres of dune, 4,320 acres of supratidal

habitat, and 1,048 acres of intertidal habitat. Each of the islands in the NER plan will require at least

one beach/dune renourishment event in order to maintain their geomorphologic form and ecologic

function throughout the 50-year period of analysis. Marsh renourishment was not included since the

initial restoration plan provides for significant intertidal habitat throughout the 50 year period of

analysis. The individual island plans are described in detail below.

1. Raccoon Island Plan E with Terminal Groin (Figure 2): The dune would be constructed to a

height of +7.7 feet North American Vertical Datum 1988 (NAVD 88) with a dune crown width

of 100 feet. The dune elevation takes into account that there will be approximately 1.7 feet of

vertical adjustments (eustatic sea level rise, subsidence, and compaction) occurring during the

first six months after construction. At the end of the six-month period, the dune should reach

the design elevation of 6 feet NAVD 88. The marsh fill is proposed on the landward side of the

dune at an elevation of +3.7 feet NAVD 88. The dune and marsh elevations are considerably

higher than those planned for Trinity and Whiskey Islands for two reasons: (1) Plan E is


TBBSR biological opinion| Page 3

designed to withstand 25 years rather than 5 years of additional background erosion; and (2) the

higher elevation of the 25-year plan results in a higher compaction rate. Fill quantities for the

dune/beach and marsh components are 5.2 million and 5.1 million cubic yards, respectively.

For the dune area, the material will be dredged from the Ship Shoal Outer Continental Shelf

(OCS) area. For the marsh area, the material will be dredged from the Raccoon Island TE-48

borrow area; however, the borrow area does not have enough material to construct the marsh in

its entirety. Therefore, approximately 2.7 million cubic yards of sand will be dredged from

Ship Shoal to provide a base layer for the marsh. Approximately 11,912 feet of sand fencing

will be installed along the dune to promote deposition of windblown sand. At TY1, this plan

would add 554 acres of habitat (dune, intertidal, and supratidal) to the existing 235-acre island

footprint, increasing the size of the island to 789 acres. The result would be 63 acres of dune,

688 acres of supratidal, and 38 acres of intertidal habitat. This plan would require one

renourishment interval at TY30 that would consist of a lesser amount of sediment placement.

In 1997, eight detached and segmented breakwaters were installed along the Gulf shoreline of

Raccoon Island as part of a Coastal Wetlands Planning, Protection, and Restoration Act

(CWPPRA) project (TE-29) to reduce shoreline retreat, promote sediment deposition along the

beach, and to protect shorebird habitat. Due to the success of the TE-29 breakwaters, eight

additional breakwaters were constructed to the west of the original breakwaters as part of a

separate CWPPRA project (TE-48) that was completed in 2007. Project TE-48 also included

the creation of approximately 60 acres of emergent and intertidal back-barrier marsh, which has

yet to be constructed. Raccoon Plan E was designed to complement the marsh creation portion

of TE-48 and to avoid impacting approximately 58 acres of existing mangroves adjacent to

project TE-48. A terminal groin will also be constructed as part of Raccoon Island Plan E. The

terminal groin will be approximately 1,200-feet-long and 75-feet-wide and will be installed at

the western terminus of the island to prevent sediment migration out of the Isles Dernieres

system.

2. Whiskey Island Plan C (Figure 3): The dune would be constructed to a height of +6.4 feet

NAVD 88 with a dune crown width of 100 feet. The dune elevation takes into account that

there will be approximately 0.4 feet of vertical adjustments (eustatic sea level rise, subsidence,

and compaction) occurring during the first six months after construction. At the end of the sixmonth period, the dune should reach the design elevation of 6 feet NAVD 88. The marsh fill is

proposed on the landward side of the dune at an elevation of +2.4 feet NAVD 88. Although the

design elevation for the marsh is 1.6 feet NAVD 88, the marsh will be constructed at a higher

elevation to account for initial vertical adjustments. The plan will utilize beach/dune material

from the Ship Shoal OCS borrow area and marsh material from the Whiskey 3A borrow area.

Fill quantities for the initial construction of the dune/beach and marsh components are 8.3

million and 0.6 million cubic yards, respectively. Approximately 18,075 feet of sand fencing

will be installed along the dune to promote deposition of windblown sand. This plan was

designed to avoid impacting approximately 286 acres of existing mangroves on the island in

order to minimize the ecological impact during construction. At TY1 this plan would restore a

total of 1,272 acres of dune, supratidal, and intertidal habitat. This plan will require two

renourishment intervals. The first would occur at TY20 that would consist of the same amount

of dune and supratidal beach habitat that was originally created in TY1. The second

renourishment interval would occur at TY40 that would consist of a lesser amount of sediment

placement.


TBBSR biological opinion| Page 4

3. Trinity Island Plan C (Figure 4): The dune would be constructed to a height of +6.4 feet NAVD

88 with a dune crown width of 100 feet. The dune elevation takes into account that there will

be approximately 0.4 feet of vertical adjustments (eustatic sea level rise, subsidence, and

compaction) occurring during the first six months after construction. At the end of the sixmonth period, the dune should reach the design elevation of 6 feet NAVD 88. The marsh fill is

proposed on the landward side of the dune at an elevation of +2.5 feet NAVD 88, and accounts

for vertical adjustments (e.g., higher compaction rates due to the existing topography of this

island) occurring after the first six months of construction. This plan will also utilize

beach/dune material from Ship Shoal OCS and marsh materials from the Whiskey 3A borrow

area. Fill quantities for the initial construction of the dune/beach and marsh components of

Trinity Plan C are 3.1 million and 4.0 million cubic yards, respectively. Approximately 22,467

feet of sand fencing will be installed along the dune to promote deposition of windblown sand.

At TY1, this plan would add 585 acres of habitat (dune, intertidal, and supratidal) to the

existing 564-acre island footprint, increasing the size of the island to 1,149 acres. The result

would be 129 acres of dune, 456 acres of supratidal, and 564 acres of intertidal habitat. (Please

note that this project design does not include the eastern portion of the island located east of

New Cut, which is also called East Island. The islands are no longer separated by New Cut

because the cut began filling in naturally and was further restored by a CWPPRA project in

2007.) This plan would require one renourishment interval at TY25 that would consist of the

same amount of dune and supratidal beach habitat that was originally created in TY1.

4. Timbalier Island Plan E (Figure 5): The dune would be constructed to a height of +7.1 feet

NAVD 88 with a dune crown width of 100 feet. The dune elevation takes into account that

there will be approximately 1.1 feet of vertical adjustments (eustatic sea level rise, subsidence,

and compaction) occurring during the first six months after construction. At the end of the sixmonth period, the dune should reach the design elevation of 6 feet NAVD 88. The marsh fill is

proposed on the landward side of the dune at an elevation of +3.2 feet NAVD 88. The dune

and marsh elevations are considerably higher than those planned for Trinity and Whiskey

Islands for two reasons: (1) Plan E is designed to withstand 25 years rather than 5 years of

additional background erosion, and (2) the higher elevation of the 25-year plan results in a

higher compaction rate. Fill quantities for the dune/beach and marsh components of Timbalier

Plan E are 10.7 million and 9.1 million cubic yards, respectively. Timbalier Plan E will utilize

beach/dune material from the South Pelto OCS area and marsh materials from the Whiskey 3A

borrow area. However, the marsh borrow area does not have adequate material to construct the

marsh in its entirety. Therefore, approximately 8.6 million cubic yards of sand will be dredged

from the South Pelto OCS area, the sandy portions of the Whiskey 3A borrow area, and the

New Cut borrow area to provide a base layer for the marsh. The marsh material from the

Whiskey 3A borrow area will be deposited on the sand material to provide an adequate

foundation for the marsh. Approximately 35,425 feet of sand fencing will be installed. At

TY1, this would add 1,675 acres of habitat (dune, intertidal, and supratidal) to the existing 955-

acre island footprint, increasing the size of the island to 2,630 acres. The result would be 215

acres of dune, 2,346 acres of supratidal, and 69 acres of intertidal habitat. This plan would

require one renourishment interval at TY30 that would consist of a lesser amount of sediment

placement.

Dredging of offshore borrow areas would be conducted using a hydraulic cutter-head dredge, for

which the Corps has already conducted section 7 consultation with the NMFS. The dredged material

would be transported to an island using a booster pump(s) and submerged sediment pipeline. Borrow

locations are located sufficient distance from the restoration sites that they will not impact littoral drift


TBBSR biological opinion| Page 5

or project longevity. The following specific construction actions would be implemented for all four

island plans:

a) For the dune areas, the dredged material would be deposited on the beach and re-worked by

bulldozers and front-end loaders.

b) For the marsh creation areas, containment dikes would be constructed around its perimeter

using existing material dredged from inside that marsh creation area using either a bucket

dredge or a track hoe.

c) All dredging and discharge operations will be completed in a manner that will minimize

turbidity of the water at the dredge site and the discharge site.

d) Sand fencing will be installed to promote deposition of windblown sand, create dune features,

reduce trampling of existing dunes by beach visitors, and protect vegetative plantings.

e) Vegetative plantings will include a variety of native dune and marsh grass species, and the

recommended planting density is no greater than 8-foot centers.

Construction for the initial NER plan would be divided into two separate contracts. Contract 1 would

consist of Whiskey, Trinity, and Raccoon Islands for which total construction time is estimated at

approximately 4 years (49.2 months). Contract 2 would consist of Timbalier Island for which total

construction time is estimated at approximately 3.5 years (40.1 months). According to the BA, the

NER plan cannot be constructed all at once because it exceeds the authorized cost in the Water

Resources Development Act of 2007; however, the Corps plans to seek authorization to eventually

restore all four islands. Consequently, the Corps plans to only construct a subset of that plan (i.e.,

Whiskey Island Plan C only) which is recommended as the Tentatively Selected Plan (TSP).

Construction for the TSP would consist of one contract for Whiskey Island Plan C for which total

construction time is estimated at approximately 16.6 months. The Corps anticipates beginning

construction of the TSP in June 2012.

Since Whiskey Island is considered a valuable wildlife habitat (as part of the Isles Dernieres Barrier

Islands Wildlife Refuge) and the Louisiana Department of Wildlife and Fisheries (LDWF) is

reestablishing a pelican rookery on the island, maintaining adequate areas of healthy beach, dune, and

marsh is particularly important for the island. The island is also designated as critical habitat for the

piping plover and contains valuable stopover habitat for migratory birds.

Although the project footprints of the Corps plans for Raccoon, Whiskey, and Trinity Islands would

not encompass the entire islands (in contrast, all of Timbalier Island would be affected), project effects

would occur along the entire island chain due to the dynamic nature of coastal processes and the longtransport of sediments within the subject barrier island system. All of the project-area islands are also

designated as piping plover critical habitat (described in detail in the Species/critical habitat

description and Status of the species within the action area sections of this document). Therefore,

the Service has described the action area to include all of Whiskey, Raccoon, Trinity/East, and

Timbalier Islands and their associated sand and mud flats for reasons that will be explained and

discussed in detail in the EFFECTS OF THE ACTION section of this consultation.

STATUS OF THE SPECIES/CRITICAL HABITAT

Species/critical habitat description

The piping plover is a small, pale sand-colored shorebird, about seven inches long with a wingspan of

about 15 inches (Palmer 1967). On January 10, 1986, the piping plover was listed as endangered in the


TBBSR biological opinion| Page 6

Great Lakes watershed and threatened elsewhere within its range, including migratory routes outside of

the Great Lakes watershed and wintering grounds (Service 1985). Piping plovers were listed

principally because of habitat destruction and degradation, predation, and human disturbance.

Protection of the species under the Act reflects the species precarious status range-wide. Three

separate breeding populations have been identified, each with its own recovery criteria: the northern

Great Plains (threatened), the Great Lakes (endangered), and the Atlantic Coast (threatened). The

piping plover winters in coastal areas of the United States (U.S.) from North Carolina to Texas, and

along the coast of eastern Mexico and on Caribbean islands from Barbados to Cuba and the Bahamas

(Haig and Elliott-Smith 2004). Piping plover subspecies are phenotypically indistinguishable, and

most studies in the nonbreeding range report results without regard to breeding origin. Although a

recent analysis shows strong patterns in the wintering distribution of piping plovers from different

breeding populations, partitioning is not complete and major information gaps persist. Therefore,

information summarized here pertains to the species as a whole (i.e., all three breeding populations),

except where a particular breeding population is specified (Figure 6).

The Service has designated critical habitat for the piping plover on three occasions. Two of these

designations protected different breeding populations. Critical habitat for the Great Lakes breeding

population was designated May 7, 2001 (66 Federal Register (FR) 22938; Service 2001a), and critical

habitat for the northern Great Plains breeding population was designated September 11, 2002 (67 FR

57637; Service 2002). The Service designated critical habitat for wintering piping plovers on July 10,

2001 (66 FR 36038; Service 2001b). Wintering piping plovers may include individuals from the Great

Lakes and northern Great Plains breeding populations as well as birds that nest along the Atlantic

coast.

Designated wintering piping plover critical habitat originally included 142 areas (the rule states 137

units; this is in error) encompassing about 1,793 miles of mapped shoreline and 165,211 acres of

mapped areas along the coasts of North Carolina, South Carolina, Georgia, Florida, Alabama,

Mississippi, Louisiana, and Texas. Since the designation of wintering critical habitat, 19 units (TX3,4,7-10, 14-19, 22, 23, 27,28, and 31-33) in Texas have been vacated and remanded back to the

Service for reconsideration by Court order (Texas General Land Office v. U.S. Department of Interior,

Case No. V-06-CV-00032). On May 19, 2009, the Service published a final rule designating 18

revised critical habitat units in Texas, totaling approximately 139,029 acres (74 FR 23476). The

Courts also vacated and remanded back to the Service for reconsideration, four units in North Carolina

(Cape Hatteras Access Preservation Alliance v. U.S. Department of Interior, 344 F. Supp. 2d 108

(D.D.C. 2004)). The four critical habitat units vacated were NC-1, 2, 4, and 5, and all occurred within

Cape Hatteras National Seashore (CAHA). A revised designation for these four units was published

on October 21, 2008 (73 FR 62816).

The primary constituent elements (PCEs) for piping plover wintering habitat are those biological and

physical features that are essential to the conservation of the species. The PCEs are those habitat

components that support foraging, roosting, and sheltering and the physical features necessary for

maintaining the natural processes that support these habitat components. These areas typically include

coastal areas that support intertidal beaches and flats and associated dune systems and flats above

annual high tide (Service 2001a). PCEs of wintering piping plover critical habitat include sand or mud

flats (or both) with no or sparse emergent vegetation. Adjacent unvegetated or sparsely vegetated

sand, mud, or algal flats above high tide are also important, especially for roosting piping plovers

(Service 2001a). Important components of the beach/dune ecosystem include surf-cast algae, sparsely

vegetated back beach and salterns, spits, and washover areas. Washover areas are broad, unvegetated

zones, with little or no topographic relief, that are formed and maintained by the action of hurricanes,


TBBSR biological opinion| Page 7

storm surge, or other extreme wave action. The units designated as critical habitat are those areas that

have consistent use by piping plovers and that best meet the biological needs of the species. The

amount of wintering habitat included in the designation appears sufficient to support future recovered

populations, and the existence of this habitat is essential to the conservation of the species. Additional

information on each specific unit included in the designation can be found at 66 FR 36038 (Service

2001a).

Activities that affect PCEs include those that directly or indirectly alter, modify, or destroy the

processes that are associated with the formation and movement of barrier islands, inlets, and other

coastal landforms. Those processes include erosion, accretion, succession, and sea-level change. The

integrity of the habitat components also depends upon daily tidal events and regular sediment transport

processes, as well as episodic, high-magnitude storm events (Service 2001b).

Life History

Piping plovers live an average of five years, although studies have documented birds as old as 11

(Wilcox 1959) and 15 years. Breeding activity begins in mid-March when birds begin returning to

their nesting areas (Coutu et al. 1990; Cross 1990; Goldin et al. 1990; MacIvor 1990; Hake 1993).

Plovers are known to begin breeding as early as one year of age (MacIvor 1990; Haig 1992); however,

the percentage of birds that breed in their first adult year is unknown. Piping plovers generally fledge

only a single brood per season, but may re-nest several times if previous nests are lost.

The most consistent finding in the various population viability analyses conducted for piping plovers

indicates that even small declines in adult and juvenile survival rates will cause very substantial

increases in extinction risk (Ryan et al. 1993; Melvin and Gibbs 1996; Plissner and Haig 2000;

Wemmer et al. 2001; Larson et al. 2002; Amirault et al. 2005; Calvert et al. 2006; Brault 2007). A

banding study conducted between 1998 and 2004 in Atlantic Canada found lower return rates of

juvenile (first year) birds to the breeding grounds than was documented for Massachusetts (Melvin and

Gibbs 1994; Service 1996), Maryland (Loegering 1992), and Virginia (Cross 1996) breeding

populations in the mid-1980s and very early 1990s. This is consistent with failure of the Atlantic

Canada population to increase in abundance despite very high productivity (relative to other breeding

populations) and extremely low rates of dispersal to the U.S. over the last 15 plus years (Amirault et al.

2005). Simply stated, this suggests that maximizing productivity does not ensure population increases.

Efforts to partition survival within the annual cycle are beginning to receive more attention, but current

information remains limited. Drake et al. (2001) observed no mortality among 49 radio-marked piping

plovers (total of 2,704 transmitter days) in Texas in 2007-2008. Cohen et al. (2008a) documented no

mortality of 7 radio-tracked wintering piping plovers at Oregon Inlet from December 2005 to March

2006. They speculate their high survival rate was attributed to plover food availability much of the day

as well as the low occurrence of days below freezing and infrequent wet weather. Analysis of South

Carolina resighting data for 87 banded piping plovers (78 percent Great Lakes breeders) in 2006-2007

and 2007-2008 found 100 percent survival from December to April1 (Cohen pers. comm. 2009 ). Noel

et al. (2007) inferred two winter (November to February) mortalities2 among 21 banded (but not radio-

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1 However, of those birds, one unique and one non-uniquely banded piping plover were seen in the first winter and were resighted multiple times in the

second fall at the same location but were not seen during the second winter; whether these two birds died in the fall or shifted their wintering location is

unknown (Maddock et al. 2009).

2 Noel et al. (2007) inferred mortality if a uniquely banded piping plover with multiple November to February sightings on the survey site disappeared

during that time and was never observed again in either its nonbreeding or breeding range. Note that most of these birds were from the Great Lakes

breeding population, where detectability during the breeding season is very high.


TBBSR biological opinion| Page 8

tagged) overwintering piping plovers in 2003-2004 and 9 mortalities among 19 overwintering birds

during the winter of 2004-2005 at Little St. Simons Island, Georgia. LeDee (2008) found higher

apparent survival3 rates during breeding and southward migration than during winter and northward

migration for 150 adult (i.e., after-hatch year) Great Lakes piping plovers.

Mark-recapture analysis of resightings of uniquely banded piping plovers from seven breeding areas

by Roche et al. (2009) found that apparent adult survival declined in four populations and increased in

none over the life of the studies4

. Some evidence of correlation in year-to-year fluctuations in annual

survival of Great Lakes and eastern Canada populations, both of which winter primarily along the

southeastern U.S. Atlantic Coast, suggests that shared over-wintering and/or migration habitats may

influence annual variation in survival. Further concurrent mark-resighting analysis of color-banded

individuals across piping plover breeding populations has the potential to shed light on threats that

affect survival in the migration and wintering range. However, very little to no information exists

specifically for birds wintering along the northern Gulf of Mexico.

Migration

Plovers depart their breeding grounds for their wintering grounds from July through late August, but

southward migration extends through November. Piping plovers spend up to 10 months of their life

cycle on their migration and winter grounds, generally July 15 through as late as May 15. Piping

plovers migrate through and winter in coastal areas of the U.S. from North Carolina to Texas and in

portions of Mexico and the Caribbean. Both spring and fall migration routes of Atlantic Coast

breeders are believed to occur primarily within a narrow zone along the Atlantic Coast (Service 1996).

The pattern of both fall and spring counts at many Atlantic Coast sites demonstrates that many piping

plovers make intermediate stopovers lasting from a few days up to one month during their migrations

(Noel et al. 2005; Stucker and Cuthbert 2006). Some mid-continent breeders travel up or down the

Atlantic Coast before or after their overland movements (Stucker and Cuthbert 2006). Use of inland

stopovers during migration is also documented (Pompei and Cuthbert 2004). The source breeding

population of a given wintering individual cannot be determined in the field unless it has been banded

or otherwise marked. Information from observation of color-banded piping plovers indicates that the

winter ranges of the breeding populations overlap to a significant degree. See the Status and

Distribution section for additional information pertaining to population distribution on the wintering

grounds. While piping plover migration patterns and needs remain poorly understood and occupancy

of a particular habitat may involve shorter periods relative to wintering, information about the

energetics of avian migration indicates that this might be a particularly critical time in the species life

cycle.

Foraging

Behavioral observation of piping plovers on the wintering grounds suggests that they spend the

majority of their time foraging (Nicholls and Baldassarre 1990a; Drake 1999a, 1999b). Feeding

activities may occur during all hours of the day and night (Staine and Burger 1994; Zonick 1997), and

at all stages in the tidal cycle (Goldin 1993; Hoopes 1993). Wintering plovers primarily feed on

invertebrates such as polychaete marine worms, various crustaceans, fly larvae, beetles, and

occasionally bivalve mollusks (Bent 1929; Nicholls 1989; Zonick and Ryan 1996). They peck these

------------------------------------------------------

3 Apparent survival does not account for permanent emigration. If marked individuals leave a survey site, apparent survival rates will be lower than true

survival. If a survey area is sufficiently large, such that emigration out of the site is unlikely, apparent survival will approach true survival.

4 Data were analyzed for 3 to 11 years per breeding area, all between 1998 and 2008.


TBBSR biological opinion| Page 9

invertebrates on top of the soil or just beneath the surface. Plovers forage on moist substrate features

such as intertidal portions of ocean beaches, washover areas, mudflats, sand flats, algal flats, shoals,

wrack lines, sparse vegetation, shorelines of coastal ponds, lagoons, ephemeral pools and adjacent to

salt marshes (Gibbs 1986; Zivojnovich 1987; Nichols 1989; Nicholls and Baldassarre 1990a; Nicholls

and Baldassarre 1990b; Coutu et al. 1990; Hoopes et al. 1992; Loegering 1992; Goldin 1993; EliasGerken 1994; Wilkinson and Spinks 1994; Zonick 1997; Service 2001a). Studies from the coastal

breeding range have shown that the relative importance of various feeding habitat types may vary by

site (Gibbs 1986; Coutu et al. 1990; McConnaughey et al. 1990; Loegering 1992; Goldin 1993;

Hoopes 1993). Cohen et al. (2006) documented more abundant prey items and biomass on sound

island and sound beaches than the ocean beach. On the wintering grounds, Ecological Associates, Inc.

(2009) observed that during piping plover surveys at St. Lucie Inlet, Martin County, Florida, intertidal

mudflats and/or shallow subtidal grass flats appear to have greater value as foraging habitat than the

unvegetated intertidal areas of a flood shoal.

Roosting

Several studies identified wrack (organic material including seaweed, seashells, driftwood, and other

materials deposited on beaches by tidal action) as an important component of roosting habitat for

nonbreeding piping plovers. Lott et al. (2009) found greater than 90 percent of roosting piping plovers

in southwest Florida in old wrack with the remainder roosting on dry sand. In South Carolina, 45

percent of roosting piping plovers were in old wrack, and 18 percent were in fresh wrack. The

remainder of roosting birds used intertidal habitat (22 percent), backshore (defined as zone of dry sand,

shell, cobble and beach debris from mean high water line up to the toe of the dune)(8 percent),

washover and ephemeral pools 2 percent and 1 percent respectively (Maddock et al. 2009). Thirty

percent of roosting piping plovers in northwest Florida were observed in wrack substrates with 49

percent on dry sand and 20 percent using intertidal habitat (Smith 2007). In Texas, sea grass debris

(bay-shore wrack) was an important feature of piping plover roost sites (Drake 1999b). Mean

abundance of two other plover species in California, including the listed western snowy plover

(Charadrius alexandrinus nivosus), was positively correlated with abundance of wrack during the

nonbreeding season (Dugan et al. 2003).

Natural protection

Cryptic coloration is a primary defense mechanism for this species. Nests, adults, and chicks all blend

in with their typical beach surroundings. Piping plovers on wintering and migration grounds respond

to intruders (pedestrian, avian and mammalian) usually by squatting, running, and flushing (flying).

Habitat

Wintering piping plovers prefer coastal habitat that include sand spits, islets (small islands), tidal flats,

shoals (usually flood tidal deltas), and sandbars that are often associated with inlets (Harrington 2008).

Sandy mud flats, ephemeral pools, and overwash areas are also considered primary foraging habitats.

These substrate types have a richer infauna than the foreshore of high energy beaches and often attract

large numbers of shorebirds (Cohen et al. 2006). Wintering plovers are dependent on a mosaic of

habitat patches and move among these patches depending on local weather and tidal conditions

(Nicholls and Baldassarre 1990a).

Recent study results in North Carolina, South Carolina, and Florida complement information from

earlier investigations in Texas and Alabama (summarized in the 1996 Atlantic Coast and 2003 Great


TBBSR biological opinion| Page 10

Lakes Recovery Plans) regarding habitat use patterns of piping plovers in their coastal migration and

wintering range. Maddock et al. (2009) observed shifts to roosting habitats and behaviors during hightide periods in South Carolina. In South Carolina, exposed intertidal areas were the dominant foraging

substrate (accounting for 94 percent of observed foraging piping plovers; Maddock et al. 2009). As

observed in Texas studies, Lott et al. (2009) identified bay beaches (bay shorelines as opposed to

ocean-facing beaches) as the most common landform used by foraging piping plovers in southwest

Florida. In northwest Florida, however, Smith (2007) reported landform use by foraging piping

plovers about equally divided between Gulf of Mexico (ocean-facing) and bay beaches. Exposed

intertidal areas were the dominant foraging substrate in South Carolina (accounting for 94 percent of

observed foraging piping plovers; Maddock et al. 2009) and in northwest Florida (96 percent of

foraging observations; Smith 2007). In southwest Florida, Lott et al. (2009) found approximately 75

percent of foraging piping plovers on intertidal substrates.

Atlantic Coast and Florida studies highlighted the importance of inlets for non-breeding piping plovers.

Almost 90 percent of observations of roosting piping plovers at ten coastal sites in southwest Florida

were on inlet shorelines (Lott et al. 2009). Piping plovers were among seven shorebird species found

more often than expected (p = 0.0004; Wilcoxon Scores test) at inlet locations versus non-inlet

locations in an evaluation of 361 International Shorebird Survey sites from North Carolina to Florida

(Harrington 2008).

Recent geographic analysis of piping plover distribution on the upper Texas coast noted major

concentration areas at the mouths of rivers and washover passes (low, sparsely vegetated barrier island

habitats created and maintained by temporary, storm-driven water channels) into major bay systems

(Arvin 2008). Earlier studies in Texas have drawn attention to washover passes, which are commonly

used by piping plovers during periods of high bay-shore tides and during the spring migration period

(Zonick 1997; Zonick 2000). Cobb (in Elliott-Smith et al. 2009) reported piping plover concentrations

on exposed sea grass beds and oyster reefs during seasonal low water periods in 2006.

The effects of dredge-material deposition merit further study. Drake et al. (2001) concluded that

conversion of southern Texas mainland bay-shore tidal flats to dredged material impoundments results

in a net loss of habitat for wintering piping plovers, because impoundments eventually convert to

upland habitat not used by piping plovers. Zonick et al. (1998) reported that dredged material

placement areas along the Intracoastal Waterway in Texas were rarely used by piping plovers, and

noted concern that dredge islands block wind-driven water flows, which are critical to maintaining

important shorebird habitats. By contrast, most of the sound islands used by foraging piping plovers at

Oregon Inlet, North Caroline, were created by the Corps by deposition of dredged material in the

subtidal bay bottom, with the most recent deposition ranging from 28 to less than 10 years prior to the

study (Cohen et al. 2008a).

Mean home range size (95 percent of locations) for 49 radio-marked piping plovers in southern Texas

in 1997-98 was 12.6 square-kilometers (km2

) (3,113 acres), mean core area (50 percent of locations)

was 2.9 km2 (717 acres), and mean linear distance moved between successive locations (1.97 + 0.04

days apart), averaged across seasons, was 3.3 km (2.1 miles) (Drake 1999b; Drake et al. 2001). Seven

radio-tagged piping plovers used a 20.1 km2 (4,967 acres) area (100 percent minimum convex

polygon) at Oregon Inlet in 2005-2006, and piping plover activity was concentrated in 12 areas totaling

2.2 km2 (544 acres) (Cohen et al. 2008a). Noel and Chandler (2008) observed high fidelity of banded

piping plovers to 1 km to 4.5 km (0.62 to 2.8 miles) sections of beach on Little St. Simons Island,

Georgia.


TBBSR biological opinion| Page 11

Population dynamics

The 2006 Piping Plover Breeding Census, the last comprehensive survey throughout the breeding

grounds, documented 3,497 breeding pairs with a total of 8,065 birds throughout Canada and U.S

(Elliott-Smith et al. 2009).

Northern Great Plains Population

The Northern Great Plains plover breeds from Alberta to Manitoba, Canada, and south to Nebraska;

although some nesting has recently occurred in Oklahoma. Currently the most westerly breeding

piping plovers in the United States occur in Montana and Colorado. The decline of piping plovers on

rivers in the Northern Great Plains has been largely attributed to the loss of sandbar island habitat and

forage base due to dam construction and operation. Nesting occurs on sand flats or bare shorelines of

rivers and lakes, including sandbar islands in the upper Missouri River system, and patches of sand,

gravel, or pebbly-mud on the alkali lakes of the northern Great Plains. Plovers do nest on shorelines of

reservoirs created by the dams, but reproductive success is often low and reservoir habitat is not

available in many years due to high water levels or vegetation. Dams operated with steady constant

flows allow vegetation to grow on potential nesting islands, making these sites unsuitable for nesting.

Population declines in alkali wetlands are attributed to wetland drainage, contaminants, and predation.

The International Piping Plover Census (IPPC), conducted every five years, also estimates the number

of piping plover pairs in the Northern Great Plains. As illustrated in Table 2, none of the IPPC

estimates of the number of pairs in the U.S. suggests that the Northern Great Plains population has yet

satisfied the recovery criterion of 2,300 pairs (Plissner and Haig 1997; Ferland and Haig 2002; ElliotSmith et al. 2009). The IPPC count in prairie Canada reported 1,703 adult birds in 2006, which is also

short of the goal of 2,500 adult piping plover as stated in the Services Recovery Plan (Service 1988).

Table 2. The number of adult piping plovers and breeding pairs reported in the U.S. Northern

Great Plains by the IPPC efforts. (Sources: Plissner and Haig 1997, Ferland and Haig 2002,

Elliot-Smith et al. 2009)

Year Adults Pairs Reported

by the Census

1991 2,023 891

1996 1,599 586

2001 1,981 899

2006 2,959 1,212

The IPPC indicates that the U.S. population decreased between 1991 and 1996, then increased in 2001

and 2006. The Canadian population showed the reverse trend for the first three censuses, increasing

slightly as the U.S. population decreased, and then decreasing in 2001. Combined, the IPPC numbers

suggest that the population declined from 1991 through 2001, then increased almost 58 percent

between 2001 and 2006 (Elliott-Smith et al. 2009).

The increase in 2006 is likely due in large part to a multi-year drought across much of the region

starting in 2001 that exposed thousands of acres of nesting habitat. The Corps ran low flows on the

riverine stretches of the Missouri River for most of the years between censuses, allowing more habitat


TBBSR biological opinion| Page 12

to be exposed and resulting in relatively high fledging ratios (Corps 2009). The Corps also began to

construct habitat using mechanical means (dredging sand from the riverbed) on the Missouri River in

2004, providing some new nesting and foraging habitat. The drought also caused reservoir levels to

drop on many reservoirs throughout the Northern Great Plains (e.g., Missouri River Reservoirs in

North and South Dakota, and Lake McConaughey in Nebraska), providing previously unavailable

shoreline habitat. The population increase may also be partially due to more intensive management

activities on the alkali lakes, with increased management actions to improve habitat and reduce

predation pressures.

While the IPPC provides an index to the piping plover population, the design does not always provide

sufficient information to understand the populations dynamics. The five-year time interval between

IPPC efforts may be too long to allow managers to get a clear picture of what the short-term population

trends are and to respond accordingly if needed. As noted above, the first three IPPCs (1991, 1996,

and 2001) showed a declining population, while the fourth (2006) indicated a dramatic population

rebound of almost 58 percent for the combined U.S. and Canada Northern Great Plains population

between 2001 and 2006. With only four data points over 15 years, it is impossible to determine if and

to what extent the apparent upswing reflects a real population trend versus error(s) in the 2006 census

count and/or a previous IPPC. The 2006 IPPC included a detectability component, in which a number

of pre-selected sites were visited twice by the same observer(s) during the two-week window to get an

estimate of error rate. This study found an approximately 76 percent detectability rate through the

entire breeding area, with a range of between 39 percent to 78 percent detectability among habitat

types in the Northern Great Plains.

Such a reported large increase in population may indeed indicate a positive population trend, but with

the limited data available, it is impossible to determine how much. Furthermore, with the next IPPC

not scheduled until 2011, there is limited feedback in many areas on whether this increase is being

maintained or if the population is declining in the interim. Additionally, the results from the IPPC

have been slow to be released, adding to the time lag between data collection and possible

management response.

Great Lakes Population

The Great Lakes plovers once nested on Great Lakes beaches in Illinois, Indiana, Michigan,

Minnesota, New York, Ohio, Pennsylvania, Wisconsin, and Ontario. Great Lakes piping plovers nest

on wide, flat, open, sandy or cobble shoreline with very little grass or other vegetation. Reproduction

is adversely affected by human disturbance of nesting areas and predation by foxes, gulls, crows and

other avian species. Shoreline development, such as the construction of marinas, breakwaters, and

other navigation structures, has adversely affected nesting and brood rearing.

The Recovery Plan (Service 2003) sets a population goal of at least 150 pairs (300 individuals), for at

least 5 consecutive years, with at least 100 breeding pairs (200 individuals) in Michigan and 50

breeding pairs (100 individuals) distributed among sites in other Great Lakes states.

The Great Lakes piping plover population, which has been traditionally represented as the number of

breeding pairs, has increased since the completion of the recovery plan in 2003 (Cuthbert and Roche

2006, 2007; Westbrock et al. 2005; Stucker and Cuthbert 2004; Stucker et al. 2003). The Great Lakes

piping plover recovery plan documents the 2002 population at 51 breeding pairs (Service 2003). The

most recent census conducted in 2008 found 63 breeding pairs, an increase of approximately 23

percent. Of these, 53 pairs were found nesting in Michigan, while 10 were found outside the state,


TBBSR biological opinion| Page 13

including six pairs in Wisconsin and four in Ontario, Canada. The 53 nesting pairs in Michigan

represent approximately 50 percent of the recovery criterion. The 10 breeding pairs outside Michigan

in the Great Lakes basin, represents 20 percent of the goal, albeit the number of breeding pairs outside

Michigan has continued to increase over the past five years. The single breeding pair discovered in

2007 in the Great Lakes region of Canada represented the first confirmed piping plover nest there in

over 30 years, and in 2008 the number of nesting pairs further increased to four.

In addition, the number of non-nesting individuals has increased annually since 2003. Between 2003-

2008 an annual average of approximately 26 non-nesting piping plovers were observed, based on

limited data from 2003, 2006, 2007, and 2008. Although there was some fluctuation in the total

population from 2002 to 2008 the overall increase from 51 to 63 pairs combined with the increased

observance of non-breeding individuals indicates the population is increasing.

Atlantic Coast Population

The Atlantic Coast piping plover breeds on coastal beaches from Newfoundland and southeastern

Quebec to North Carolina. Historical population trends for the Atlantic Coast piping plover have been

reconstructed from scattered, largely qualitative records. Nineteenth-century naturalists, such as

Audubon and Wilson, described the piping plover as a common summer resident on Atlantic Coast

beaches (Haig and Oring 1987). However, by the beginning of the 20th Century, egg collecting and

uncontrolled hunting, primarily for the millinery trade, had greatly reduced the population, and in some

areas along the Atlantic Coast, the piping plover was close to extirpation. Following passage of the

Migratory Bird Treaty Act (40 Stat. 775; 16 U.S.C. 703-712) in 1918, and changes in the fashion

industry that no longer exploited wild birds for feathers, piping plover numbers recovered to some

extent (Haig and Oring 1985).

Available data suggest that the most recent population decline began in the late 1940s or early 1950s

(Haig and Oring 1985). Reports of local or statewide declines between 1950 and 1985 are numerous,

and many are summarized by Cairns and McLaren (1980) and Haig and Oring (1985). While Wilcox

(1939) estimated more than 500 pairs of piping plovers on Long Island, New York, the 1989

population estimate was 191 pairs (Service 1996). There was little focus on gathering quantitative data

on piping plovers in Massachusetts through the late 1960s because the species was commonly

observed and presumed to be secure. However, numbers of piping plover breeding pairs declined 50 to

100 percent at seven Massachusetts sites between the early 1970s and 1984 (Griffin and Melvin 1984).

Piping plover surveys in the early years of the recovery effort found that counts of these cryptically

colored birds sometimes went up with increased census effort, suggesting that some historic counts of

piping plovers by one or a few observers may have underestimated the piping plover population. Thus,

the magnitude of the species decline may have been more severe than available numbers imply.

Annual estimates of breeding pairs of Atlantic Coast piping plovers are based on multiple surveys at

most occupied sites. Sites that cannot be monitored repeatedly in May and June (primarily sites with

few pairs or inconsistent occupancy) are surveyed at least once during a standard nine-day count

period (Hecht and Melvin 2009).

Since its 1986 listing under the ESA, the Atlantic Coast population estimate has increased 234 percent,

from approximately 790 pairs to an estimated 1,849 pairs in 2008, and the U.S. portion of the

population has almost tripled, from approximately 550 pairs to an estimated 1,596 pairs. Even

discounting apparent increases in New York, New Jersey, and North Carolina between 1986 and 1989,

which likely were due in part to increased census effort (Service 1996), the population nearly doubled


TBBSR biological opinion| Page 14

between 1989 and 2008. The largest population increase between 1989 and 2008 has occurred in New

England (245 percent), followed by New York-New Jersey (74 percent). In the Southern (DE-MDVA-NC) Recovery Unit, overall growth between 1989 and 2008 was 66 percent, but almost threequarters of this increase occurred in just two years, 2003 to 2005. The eastern Canada population

fluctuated from year to year, with increases often quickly eroded in subsequent years; net growth

between 1989 and 2008 was 9 percent.

The overall population growth pattern was tempered by periodic rapid declines in the Southern and

Eastern Canada Recovery Units. The eastern Canada population decreased 21 percent in just three

years (2002 to 2005), and the population in the southern half of the Southern Recovery Unit declined

68 percent in seven years (1995 to 2001). The recent 64 percent decline in the Maine population, from

66 pairs in 2002 to 24 pairs in 2008, following only a few years of decreased productivity, provides

another example of the continuing risk of rapid and precipitous reversals in population growth.

Status and distribution

Nonbreeding (migrating and wintering) Range

Piping plovers spend up to 10 months of their life cycle on their migration and winter grounds,

generally July 15 through as late as May 15. Piping plover migration routes and habitats overlap

breeding and wintering habitats, and, unless banded, migrants passing through a site usually are

indistinguishable from breeding or wintering piping plovers. Migration stopovers by banded piping

plovers from the Great Lakes have been documented in New Jersey, Maryland, Virginia, and North

Carolina (Stucker and Cuthbert 2006). Migrating breeders from eastern Canada have been observed in

Massachusetts, New Jersey, New York, and North Carolina (Amirault et al. 2005). As many as 85

staging piping plovers have been tallied at various sites in the Atlantic breeding range (Perkins 2008

pers. communication), but the composition (e.g., adults that nested nearby and their fledged young of

the year versus migrants moving to or from sites farther north), stopover duration, and local

movements are unknown. Review of published records of piping plover sightings throughout North

America by Pompei and Cuthbert (2004) found more than 3,400 fall and spring stopover records at

1,196 sites. Published reports indicated that piping plovers do not concentrate in large numbers at

inland sites and that they seem to stop opportunistically. In most cases, reports of birds at inland sites

were single individuals. In general, distance between stopover locations and duration of stopovers

throughout the coastal migration range remains poorly understood.

Piping plovers migrate through and winter in coastal areas of the U.S. from North Carolina to Texas

and in portions of Mexico and the Caribbean. Four range-wide, mid-winter (late January to early

February) population surveys, conducted at five-year intervals starting in 1991, are summarized in

Table 3. Total numbers have fluctuated over time, with some areas experiencing increases and others

decreases. In 2001, 2,389 piping plovers were located during a winter census, accounting for only 40

percent of the known breeding birds recorded during a breeding census (Ferland and Haig 2002).

About 89 percent of birds that are known to winter in the U.S. do so along the Gulf Coast (Texas to

Florida), while 8 percent winter along the Atlantic Coast (North Carolina to Florida).


TBBSR biological opinion| Page 15

Table 3. Results of the 1991, 1996, 2001, and 2006 International Piping Plover Winter Censuses

(Haig et al. 2005; Elliott-Smith et al. 2009).

Location 1991 1996 2001 2006

Virginia not surveyed (NS) NS NS 1

North Carolina 20 50 87 84

South Carolina 51 78 78 100

Georgia 37 124 111 212

Florida 551 375 416 454

-Atlantic 70 31 111 133

-Gulf 481 344 305 321

Alabama 12 31 30 29

Mississippi 59 27 18 78

Louisiana 750 398 511 226

Texas 1,904 1,333 1,042 2,090

Puerto Rico 0 0 6 NS

U.S. Total 3,384 2,416 2,299 3,355

Mexico 27 16 NS 76

Bahamas 29 17 35 417

Cuba 11 66 55 89

Other Caribbean

Islands 0 0 0 28

GRAND TOTAL 3,451 2,515 2,389 3,884

Percent of Total

International

Piping Plover

Breeding Census

62.9% 42.4% 40.2% 48.2%

Regional and local fluctuations may reflect the quantity and quality of suitable foraging and roosting

habitat, which vary over time in response to natural coastal formation processes as well as

anthropogenic habitat changes (e.g., inlet relocation, dredging of shoals and spits). See, for example,

discussions of survey number changes in Mississippi, Louisiana, and Texas by Winstead, Baka, and

Cobb, respectively, in Elliott-Smith et al. (2009). Fluctuations may also represent localized weather

conditions (especially wind) during surveys, or unequal survey coverage. For example, airboats

facilitated first-time surveys of several central Texas sites in 2006 (Cobb in Elliott-Smith et al. 2009).

Similarly, the increase in the 2006 numbers in the Bahamas is attributed to greatly increased census

efforts; the extent of additional habitat not surveyed remains undetermined (Maddock and Wardle in

Elliott-Smith et al. 2009). Changes in wintering numbers may also be influenced by growth or decline

in the particular breeding populations that concentrate their wintering distribution in a given area.

Major opportunities to locate previously unidentified wintering sites are concentrated in the Caribbean

and Mexico (see pertinent sections in Elliott-Smith et al. 2009). Further surveys and assessment of

seasonally emergent habitats (e.g., sea grass beds, mudflats, oyster reefs) within bays lying between

the mainland and barrier islands in Texas are also needed.

Mid-winter surveys may substantially underestimate the abundance of nonbreeding piping plovers

using a site or region during other months. In late September 2007, 104 piping plovers were counted at

the south end of Ocracoke Island, North Carolina (NPS 2007), where none were seen during the 2006

International Piping Plover Winter Census (Elliott-Smith et al. 2009). Noel et al. (2007) observed up


TBBSR biological opinion| Page 16

to 100 piping plovers during peak migration at Little St. Simons Island, Georgia, where approximately

40 piping plovers wintered in 2003 to 2005. Differences among fall, winter, and spring counts in

South Carolina were less pronounced, but inter-year fluctuations (e.g., 108 piping plovers in spring

2007 versus 174 piping plovers in spring 2008) at 28 sites were striking (Maddock et al. 2009). Even

as far south as the Florida Panhandle, monthly counts at Phipps Preserve in Franklin County ranged

from a mid-winter low of four piping plovers in December 2006 to peak counts of 47 in October 2006

and March 2007 (Smith 2007). Pinkston (2004) observed much heavier use of Texas Gulf Coast

(ocean-facing) beaches between early September and mid-October (approximately 16 birds per mile)

than during December to March (approximately two birds per mile).

Local movements of nonbreeding piping plovers may also affect abundance estimates. At Deveaux

Bank, one of South Carolinas most important piping plover sites, five counts at approximately 10-day

intervals between August 27 and October 7, 2006, oscillated from 28 to 14 to 29 to 18 to 26 (Maddock

et al. 2009). Noel and Chandler (2008) detected banded Great Lakes piping plovers known to be

wintering on their Georgia study site in 73.8 + 8.1 percent of surveys over three years.

Abundance estimates for nonbreeding piping plovers may also be affected by the number of surveyor

visits to the site. Preliminary analysis of detection rates by Maddock et al. (2009) found 87 percent

detection during the mid-winter period on core sites surveyed three times a month during fall and

spring and one time per month during winter, compared with 42 percent detection on sites surveyed

three times per year (Cohen 2009 pers. communication).

Gratto-Trevor et al. (2009; Figure 7) found strong patterns (but no exclusive partitioning) in winter

distribution of uniquely banded piping plovers from four breeding populations. All eastern Canada

and 94 percent of Great Lakes birds wintered from North Carolina to southwest Florida. However,

eastern Canada birds were more heavily concentrated in North Carolina, and a larger proportion of

Great Lakes piping plovers were found in South Carolina and Georgia. Northern Great Plains

populations were primarily seen farther west and south, especially on the Texas Gulf Coast. Although

the great majority of Prairie Canada individuals were observed in Texas, particularly southern Texas,

individuals from the U.S. Great Plains were more widely distributed on the Gulf Coast from Florida to

Texas.

The findings of Gratto-Trevor et al. (2009) provide evidence of differences in the wintering

distribution of piping plovers from these four breeding areas. However, the distribution of birds by

breeding origin during migration remains largely unknown. Other major information gaps include the

wintering locations of the U.S. Atlantic Coast breeding population (banding of U.S. Atlantic Coast

piping plovers has been extremely limited) and the breeding origin of piping plovers wintering on the

Caribbean islands and in much of Mexico. Banded piping plovers from the Great Lakes, Northern

Great Plains, and eastern Canada breeding populations showed similar patterns of seasonal abundance

at Little St. Simons Island, Georgia (Noel et al. 2007). However, the number of banded plovers

originating from the latter two populations was relatively small at this study area.

This species exhibits a high degree of intra- and inter-annual wintering site fidelity (Nicholls and

Baldassarre 1990a; Drake et al. 2001; Noel et al. 2005; Stucker and Cuthbert 2006). Gratto-Trevor et

al. (2009) reported that six of 259 banded piping plovers observed more than once per winter moved

across boundaries of the seven U.S. regions. Of 216 birds observed in different years, only eight

changed regions between years, and several of these shifts were associated with late summer or early

spring migration periods (Gratto-Trevor et al. 2009; Figure 7).


TBBSR biological opinion| Page 17

Local movements are more common. In South Carolina, Maddock et al. (2009) documented many

cross-inlet movements by wintering banded piping plovers as well as occasional movements of up to

18 km (11 miles) by approximately 10 percent of the banded population; larger movements within

South Carolina were seen during fall and spring migration. Similarly, eight banded piping plovers that

were observed in two locations during 2006-2007 surveys in Louisiana and Texas were all in close

proximity to their original location, such as on the bay and ocean side of the same island or on

adjoining islands (Maddock 2008).

The 2004 and 2005 hurricane seasons affected a substantial amount of habitat along the Gulf Coast.

Habitats such as those along Gulf Islands National Seashore have benefited from increased washover

events, which created optimal habitat conditions for piping plovers. Conversely, hard shoreline

structures put into place following storms throughout the species range to prevent such shoreline

migration prevent habitat creation. Four hurricanes between 2002 and 2005 are often cited in reference

to rapid erosion of the Chandeleur Islands, a chain of low-lying islands in Louisiana where the 1991

IPPC tallied more than 350 piping plovers. Those same storms, however, created habitats such as

overwash fans and sand spits on barrier islands and headlands in other portions of Louisiana. (See the

Storm events section below for more details on their effects to habitat.)

The Service is aware of the following site-specific conditions that benefit several habitats piping plover

use while wintering and migrating, including critical habitat units. In Texas, one critical habitat unit

was afforded greater protection due to the acquisition of adjacent upland properties by the local

Audubon chapter. In another unit in Texas, vehicles were removed from a portion of the beach

decreasing the likelihood of automobile disturbance to plovers. Exotic plant removal that threatens to

invade suitable piping plover habitat is occurring in a critical habitat unit in South Florida. The

Service and other government agencies remain in a contractual agreement with the U.S. Department of

Agriculture (USDA) for predator control within limited coastal areas in the Florida panhandle,

including portions of some critical habitat units. Continued removal of potential terrestrial predators is

likely to enhance survivorship of wintering and migrating piping plovers. In North Carolina, one

critical habitat unit was afforded greater protection when the local Audubon chapter agreed to manage

the area specifically for piping plovers and other shorebirds following the relocation of the nearby inlet

channel.

Recovery criteria

Northern Great Plains Population (Service 1988, 1994)

1. Increase the number of birds in the U.S. northern Great Plains states to 2,300 pairs (Service

1994).

2. Increase the number of birds in the prairie region of Canada to 2,500 adult piping plovers

(Service 1988).

3. Secure long term protection of essential breeding and wintering habitat (Service 1994).

Great Lakes Population (Service 2003)

1. At least 150 pairs (300 individuals), for at least 5 consecutive years, with at least 100 breeding

pairs (200 individuals) in Michigan and 50 breeding pairs (100 individuals) distributed among

sites in other Great Lakes states.


TBBSR biological opinion| Page 18

2. Five-year average fecundity within the range of 1.5-2.0 fledglings per pair, per year, across the

breeding distribution, and ten-year population projections indicate the population is stable or

continuing to grow above the recovery goal.

3. Protection and long-term maintenance of essential breeding and wintering habitat is ensured,

sufficient in quantity, quality, and distribution to support the recovery goal of 150 pairs (300

individuals).

4. Genetic diversity within the population is deemed adequate for population persistence and can

be maintained over the long-term.

5. Agreements and funding mechanisms are in place for long-term protection and management

activities in essential breeding and wintering habitat.

Atlantic Coast Population (Service 1996)

1. Increase and maintain for 5 years a total of 2,000 breeding pairs, distributed among 4 recovery

units.

Recovery Unit Minimum Subpopulation

Atlantic (eastern) Canada 400 pairs

New England 625 pairs

New York-New Jersey 575 pairs

Southern (DE-MD-VA-NC) 400 pairs

2. Verify the adequacy of a 2,000 pair population of piping plovers to maintain heterozygosity

and allelic diversity over the long term.

3. Achieve a 5-year average productivity of 1.5 fledged chicks per pair in each of the 4 recovery

units described in criterion 1, based on data from sites that collectively support at least 90

percent of the recover units population.

4. Institute long-term agreements to assure protection and management sufficient to maintain the

population targets and average productivity in each recovery unit.

5. Ensure long-term maintenance of wintering habitat, sufficient in quantity, quality, and

distribution to maintain survival rates for a 2,000-pair population.

Threats to piping plovers/critical habitat

In the following sections, we provide an analysis of threats to piping plovers in their migration and

wintering range. We update information obtained since the 1985 listing rule, the 1991 and 2009 status

reviews, and the three breeding population recovery plans. Both previously identified and new threats

are discussed. With minor exceptions, this analysis is focused on threats to piping plovers within the

continental U.S. portion of their migration and wintering range. Threats in the Caribbean and Mexico

remain largely unknown.

Present or threatened destruction, modification, or curtailment of its habitat or range

The status of piping plovers on winter and migration grounds is difficult to assess, but threats to piping

plover habitat used during winter and migration (identified by the Service during its designation of

critical habitat) continue to affect the species. Unregulated motorized and pedestrian recreational use,

inlet and shoreline stabilization projects, beach maintenance and nourishment, and pollution affect

most winter and migration areas. Conservation efforts at some locations have likely resulted in the

maintenance or enhancement of wintering habitat.


TBBSR biological opinion| Page 19

The 1985 final listing rule stated that the number of piping plovers on the Gulf of Mexico coastal

wintering grounds might be declining as indicated by preliminary analysis of Christmas Bird Count

data. Independent counts of piping plovers on the Alabama coast indicated a decline in numbers

between the 1950s and early 1980s. At the time of listing, the Texas Parks and Wildlife Department

stated that 30 percent of wintering habitat in Texas had been lost over the previous 20 years. The final

rule also stated that in addition to extensive breeding area problems, the loss and modification of

wintering habitat was a significant threat to the piping plover.

The three recovery plans state that shoreline development throughout the wintering range poses a

threat to all populations of piping plovers. The plans further state that beach maintenance and

nourishment, inlet dredging, and artificial structures, such as jetties and groins, could eliminate

wintering areas and alter sedimentation patterns leading to the loss of nearby habitat. Priority 1 actions

in the 1996 Atlantic Coast and 2003 Great Lakes Recovery Plans identify tasks to protect natural

processes that maintain coastal ecosystems and quality wintering piping plover habitat and to protect

wintering habitat from shoreline stabilization and navigation projects. The 1988 Northern Great Plains

Recovery Plan states that, as winter habitat is identified, current and potential threats to each site

should be determined.

Important components of ecologically sound barrier beach management include perpetuation of natural

dynamic coastal formation processes. Structural development along the shoreline or manipulation of

natural inlets upsets the dynamic processes and results in habitat loss or degradation (Melvin et al.

1991). Throughout the range of migrating and wintering piping plovers, inlet and shoreline

stabilization, inlet dredging, beach maintenance and nourishment activities, and seawall installations

continue to constrain natural coastal processes. Dredging of inlets can affect spit formation adjacent to

inlets and directly remove or affect ebb and flood tidal shoal formation. Jetties, which stabilize an

island, cause island widening and subsequent growth of vegetation on inlet shores. Seawalls restrict

natural island movement and exacerbate erosion. As discussed in more detail below, all these efforts

result in loss of piping plover habitat. Construction of these projects during months when piping

plovers are present also causes disturbance that disrupts the birds foraging efficiency and hinders their

ability to build fat reserves over the winter and in preparation for migration, as well as their

recuperation from migratory flights. Additional investigation is needed to determine the extent to

which these factors cumulatively affect piping plover survival and how they may impede conservation

efforts for the species.

Any assessment of threats to piping plovers from loss and degradation of habitat must recognize that

up to 24 shorebird species migrate or winter along the Atlantic Coast and almost 40 species of

shorebirds are present during migration and wintering periods in the Gulf of Mexico region (Helmers

1992). Continual degradation and loss of habitats used by wintering and migrating shorebirds may

cause an increase in intra-specific and inter-specific competition for remaining food supplies and

roosting habitats. In Florida, for example, approximately 825 miles of coastline and parallel bayside

flats (unspecified amount) were present prior to the advent of high human densities and beach

stabilization projects. We estimate that only about 35 percent of the Florida coastline continues to

support natural coastal formation processes, thereby concentrating foraging and roosting opportunities

for all shorebird species and forcing some individuals into suboptimal habitats. Thus, intra- and interspecific competition most likely exacerbates threats from habitat loss and degradation.


TBBSR biological opinion| Page 20

Sand placement projects

In the wake of episodic storm events, managers of lands under public, private, and county ownership

often protect coastal structures using emergency storm berms; this is frequently followed by beach

nourishment or renourishment activities (nourishment projects are considered soft stabilization

versus hard stabilization such as seawalls). Berm placement and beach nourishment deposit

substantial amounts of sand along Gulf of Mexico and Atlantic beaches to protect local property in

anticipation of preventing erosion and what otherwise will be considered natural processes of

overwash and island migration (Schmitt and Haines 2003). On unpopulated islands, the addition of

sand and creation of marsh are sometimes used to counteract the loss of roosting and nesting habitat

for shorebirds and wading birds as a result of erosional storm events.

Past and ongoing stabilization projects fundamentally may alter the naturally dynamic coastal

processes that create and maintain beach strand and bayside habitats, including those habitat

components that piping plovers rely upon. Although impacts may vary depending on a range of

factors, stabilization projects may directly degrade or destroy piping plover roosting and foraging

habitat in several ways. Front beach habitat may be used to construct an artificial berm that is densely

planted in grass, which can directly reduce the availability of roosting habitat. Over time, if the beach

narrows due to erosion, additional roosting habitat between the berm and the water can be lost. Berms

can also prevent or reduce the natural overwash that creates roosting habitats by converting vegetated

areas to open sand areas. The vegetation growth caused by impeding natural overwash can also reduce

the maintenance and creation of bayside intertidal feeding habitats. In addition, stabilization projects

may indirectly encourage further development of coastal areas and increase the threat of disturbance.

Table 4. Summary of the extent of nourished beaches in piping plover wintering and migrating

habitat within the conterminous U.S. Data extracted from Service unpublished data (project files,

gray literature, and field observations).

State

Sandy beach

shoreline

miles

available

Sandy beach shoreline

miles nourished to date

(within critical habitat

units)

Percent of sandy beach

shoreline affected (within

critical habitat units)

North Carolina 301a 117e (unknown) 39 (unknown)

South Carolina 187a 56 (0.6) 30 (0.32))

Georgia 100a 8 (0.4) 8 (0.40)

Florida 825b 404 (6)f 49 (0.72)

Alabama 53a 12 (2) 23 (3.77)

Mississippi 110c >6 (0) 5 (0)

Louisiana 397a Unquantified (generally

restoration-oriented) Unknown

Texas 367d 65 (45) 18 (12.26)

Overall Total

2,340 (does

not include

Louisiana)

>668 does not include

Louisiana (54 in CH) 29% (>2.31% in CH)

(a) Data from www.50states.com; (b) Clark 1993; (c) N. Winstead, Mississippi Museum of Natural Science, in litt. 2008; (d)

www.Surfrider.org; (e) H. Hall, Service, pers. comm. 2009; (f) Partial data from Lott et al. (2007 in review).


TBBSR biological opinion| Page 21

At least 668 of 2,340 coastal shoreline miles (29 percent of beaches throughout the piping plover

winter and migration range in the U.S.) are bermed, nourished, or renourished, generally for

recreational purposes and to protect commercial and private infrastructure. However, only

approximately 54 miles or 2.31 percent of these impacts have occurred within critical habitat.

In Louisiana, the sustainability of the coastal ecosystem is threatened by the inability of the barrier

islands to maintain geomorphologic functionality (i.e., the Louisiana coastal systems are starved for

sediment sources) (Corps 2010). Consequently, most of the planned sediment placement projects are

conducted as environmental restoration projects by various Federal and State agencies because without

the sediment many areas would erode below sea level. Agencies conducting coastal restoration

projects aim to design projects that mimic the natural existing elevations of coastal habitats (e.g.,

beach, dune, and marsh) in order to allow their projects to work within and be sustained by the natural

ecosystem processes that maintain those coastal habitats. Due to the low elevation of barrier islands

and coastal headlands, placement of additional sediment in those areas generally does not reach an

elevation that would prevent the formation of washover areas or impede natural coastal processes,

especially during storm events. Such careful design of these restoration projects allows daily tidal

processes or storm events to re-work the sediments to reform the Gulf/beach interface and create

washover areas, sand flats, and mud flats on the bay-side of the islands, as well as sand spits on the

ends of the islands; thus, the added sediment aids in sustaining the barrier island system.

Sediment placement also temporarily affects the benthic fauna found in intertidal systems by covering

them with a layer of sediment. Some benthic species can burrow through a thin layer (varies from 15

to 35 inches for different species) of additional sediment since they are adapted to the turbulent

environment of the intertidal zone; however, thicker layers (i.e., greater than 40 inches) of sediment are

likely to smother the benthic fauna (Greene 2002). Various studies of such effects indicate that the

recovery of benthic fauna after beach renourishment or sediment placement can take anywhere from 6

months to 2 years. Such delayed recovery of benthic prey species temporarily affects the quality of

piping plover foraging habitat.

Inlet stabilization/relocation

Many navigable mainland or barrier island tidal inlets along the Atlantic and Gulf of Mexico coasts are

stabilized with jetties, groins, or by seawalls and/or adjacent industrial or residential development.

Jetties are structures built perpendicular to the shoreline that extend through the entire nearshore zone

and past the breaker zone to prevent or decrease sand deposition in the channel (Hayes and Michel

2008). Inlet stabilization with rock jetties and associated channel dredging for navigation alter the

dynamics of long-shore sediment transport and affect the location and movement rate of barrier islands

(Camfield and Holmes 1995), typically causing down-drift erosion. Sediment is then dredged and

added back to the islands which are subsequently widened. Once the island becomes stabilized,

vegetation encroaches on the bayside habitat, thereby diminishing and eventually destroying its value

to piping plovers. Accelerated erosion may compound future habitat loss, depending on the degree of

sea-level rise. Unstabilized inlets naturally migrate, re-forming important habitat components, whereas

jetties often trap sand and cause significant erosion of the down-drift shoreline. These combined

actions affect the availability of piping plover habitat (Cohen et al. 2008b).

Using Google Earth© (accessed April 2009), Service biologists visually estimated the number of

navigable mainland or barrier island tidal inlets throughout the wintering range of the piping plover in


TBBSR biological opinion| Page 22

the conterminous U.S. that have some form of hardened structure. This includes seawalls or adjacent

development, which lock the inlets in place (Table 5).

Table 5. Visually estimated numbers of navigable mainland and barrier island inlets and hardened

inlets by state.

State

Number of navigable

mainland and barrier

island inlets

Number of

hardened inlets

Percent of

inlets affected

North Carolina 20 2.5* 12.5%

South Carolina 34 3.5* 10.3%

Georgia 26 2 7.7%

Florida 82 41 50%

Alabama 14 6 42.9%

Mississippi 16 7 43.8%

Louisiana 40 9 22.5%

Texas 17 10 58.8%

Overall Total 249 81 32.5%

*An inlet at the state line is considered to be half an inlet counted in each state.

Tidal inlet relocation can cause loss and/or degradation of piping plover habitat; although less

permanent than construction of hard structures, effects can persist for years. For example, a project on

Kiawah Island, South Carolina, degraded one of the most important piping plover habitats in the State

by reducing the size and physical characteristics of an active foraging site, changing the composition of

the benthic community, decreasing the tidal lag in an adjacent tidal lagoon, and decreasing the

exposure time of the associated sand flats (Service and Town of Kiawah Island unpublished data). In

2006, pre-project piping plover numbers in the project area recorded during four surveys conducted at

low tide averaged 13.5 piping plovers. This contrasts with a post-project average of 7.1 plovers during

eight surveys (four in 2007 and four in 2008) conducted during the same months (Service and Town of

Kiawah Island unpublished data), indicating that habitat quality was reduced. Service biologists are

aware of at least seven inlet relocation projects (two in North Carolina, three in South Carolina, two in

Florida), but this number likely under-represents the extent of this activity.

Sand mining/dredging

Sand mining, the practice of extracting (dredging) sand from sand bars, shoals, and inlets in the

nearshore zone, is a less expensive source of sand than obtaining sand from offshore shoals for beach

nourishment. Sand bars and shoals are sand sources that move onshore over time and act as natural

breakwaters. Inlet dredging reduces the formation of exposed ebb and flood tidal shoals considered to

be primary or optimal piping plover roosting and foraging habitat. Removing these sand sources can

alter depth contours and change wave refraction as well as cause localized erosion (Hayes and Michel

2008). Exposed shoals and sandbars are also valuable to piping plovers, as they tend to receive less

human recreational use (because they are only accessible by boat) and therefore provide relatively less

disturbed habitats for birds. We do not have a good estimate of the amount of sand mining that occurs

across the piping plover wintering range, nor do we have a good estimate of the number of inlet

dredging projects that occur. This number is likely greater than the number of total jettied inlets shown

in Table 5, since most jettied inlets need maintenance dredging, but non-hardened inlets are often

dredged as well.


TBBSR biological opinion| Page 23

Groins

Groins (structures made of concrete, rip rap, wood, or metal built perpendicular to the beach in order to

trap sand) are typically found on developed beaches with severe erosion. Although groins can be

individual structures, they are often clustered along the shoreline. Groins can act as barriers to longshore sand transport and cause down-drift erosion (Hayes and Michel 2008), which prevents piping

plover habitat creation by limiting sediment deposition and accretion. These structures are found

throughout the southeastern Atlantic Coast, and although most were in place prior to the piping

plovers 1986 listing under the Act, installation of new groins continues to occur.

Seawalls and revetments

Seawalls and revetments are vertical hard structures built parallel to the beach in front of buildings,

roads, and other facilities to protect them from erosion. However, these structures often accelerate

erosion by causing scouring in front of and down-drift from the structure (Hayes and Michel 2008),

which can eliminate intertidal foraging habitat and adjacent roosting habitat. Physical characteristics

that determine microhabitats and biological communities can be altered after installation of a seawall

or revetment, thereby depleting or changing composition of benthic communities that serve as the prey

base for piping plovers. At four California study sites, each comprised of an unarmored segment and a

segment seaward of a seawall, Dugan and Hubbard (2006) found that armored segments had narrower

intertidal zones, smaller standing crops of macrophyte wrack, and lower shorebird abundance and

species richness. Geotubes (long cylindrical bags made of high-strength permeable fabric and filled

with sand) are softer alternatives, but act as barriers by preventing overwash. We did not find any

sources that summarize the linear extent of seawall, revetment, and geotube installation projects that

have occurred across the piping plovers wintering and migration habitat.

Exotic/invasive vegetation

A recently identified threat to piping plover habitat, not described in the listing rule or recovery plans,

is the spread of coastal invasive plants into suitable piping plover habitat. Like most invasive species,

coastal exotic plants reproduce and spread quickly and exhibit dense growth habits, often

outcompeting native plant species. If left uncontrolled, invasive plants cause a habitat shift from open

or sparsely vegetated sand to dense vegetation, resulting in the loss or degradation of piping plover

roosting habitat, which is especially important during high tides and migration periods.

Beach vitex (Vitex rotundifolia) is a woody vine introduced into the southeastern U.S. as a dune

stabilization and ornamental plant (Westbrooks and Madsen 2006). It currently occupies a very small

percentage of its potential range in the U.S.; however, it is expected to grow well in coastal

communities throughout the southeastern U.S. from Virginia to Florida, and west to Texas

(Westbrooks and Madsen 2006). In 2003, the plant was documented in New Hanover, Pender, and

Onslow counties in North Carolina, and at 125 sites in Horry, Georgetown, and Charleston counties in

South Carolina. One Chesapeake Bay site in Virginia was eradicated, and another site on Jekyll

Island, Georgia, is about 95 percent controlled (Suiter 2009 pers. communication). Beach vitex has

been documented from two locations in northwest Florida, but one site disappeared after erosional

storm events. The landowner of the other site has indicated an intention to eradicate the plant, but

follow through is unknown (Farley 2009 pers. communication). The task forces formed in North and

South Carolina in 2004 and 2005 have made great strides to remove this plant from their coasts. To


TBBSR biological opinion| Page 24

date, about 200 sites in North Carolina have been treated, with 200 additional sites in need of

treatment. Similar efforts are underway in South Carolina.

Unquantified amounts of crowfoot grass (Dactyloctenium aegyptium) grow invasively along portions

of the Florida coastline. It forms thick bunches or mats that may change the vegetative structure of

coastal plant communities and alter shorebird habitat. The Australian pine (Casuarina equisetifolia)

also changes the vegetative structure of the coastal community in south Florida and islands within the

Bahamas. Shorebirds prefer foraging in open areas where they are able to see potential predators, and

tall trees provide good perches for avian predators. Australian pines potentially impact shorebirds,

including the piping plover, by reducing attractiveness of foraging habitat and/or increasing avian

predation.

The propensity of these exotic species to spread, and their tenacity once established, make them a

persistent threat, partially countered by increasing landowner awareness and willingness to undertake

eradication activities.

Wrack removal and beach cleaning

Wrack on beaches and baysides provides important foraging and roosting habitat for piping plovers

(Drake 1999a; Smith 2007; Maddock et al. 2009; Lott et al. 2009) and many other shorebirds on their

winter, breeding, and migration grounds. Because shorebird numbers are positively correlated with

wrack cover and biomass of their invertebrate prey that feed on wrack (Tarr and Tarr 1987; Hubbard

and Dugan 2003; Dugan et al. 2003), beach grooming will lower bird numbers (Defreo et al. 2009).

There is increasing popularity along developed beaches in the Southeast, especially in Florida, for

beach communities to carry out beach cleaning and beach raking actions. Beach cleaning occurs

on private beaches, where piping plover use is not well documented, and on some municipal or county

beaches that are used by piping plovers. Most wrack removal on state and federal lands is limited to

post-storm cleanup and does not occur regularly.

Man-made beach cleaning and raking machines effectively remove seaweed, fish, glass, syringes,

plastic, cans, cigarettes, shells, stone, wood, and virtually any unwanted debris (Barber Beach Cleaning

Equipment 2009). These efforts remove accumulated wrack, topographic depressions, and sparse

vegetation nodes used by roosting and foraging piping plovers. Removal of wrack also eliminates a

beachs natural sand-trapping abilities, further destabilizing the beach. In addition, sand adhering to

seaweed and trapped in the cracks and crevices of wrack is removed from the beach. Although the

amount of sand lost due to single sweeping actions may be small, it adds up considerably over a period

of years (Nordstrom et al. 2006; Neal et al. 2007). Beach cleaning or grooming can result in

abnormally broad unvegetated zones that are inhospitable to dune formation or plant colonization,

thereby enhancing the likelihood of erosion (Defeo et al. 2009).

Currently, the Florida Department of Environmental Protections Beaches and Coastal Management

Systems section has issued 117 permits for beach raking or cleaning to multiple entities. We estimate

that 240 of 825 miles (29 percent) of sandy beach shoreline in Florida are cleaned or raked on various

schedules (i.e., daily, weekly, monthly) (FDEP 2008). Service biologists estimate that South Carolina

mechanically cleans approximately 34 of its 187 shoreline miles (18 percent), and Texas mechanically

cleans approximately 20 of its 367 shoreline miles (5.4 percent). In Louisiana, beach raking

occasionally occurs on Grand Isle (the states only inhabited island) along approximately 8 miles of


TBBSR biological opinion| Page 25

shoreline, roughly 2 percent of the states 397 sandy shoreline miles. We are not aware of what

percentage of mechanical cleaning occurs elsewhere in piping plover critical habitat.

Tilling beaches to reduce soil compaction, as sometimes required by the Service for sea turtle

protection after beach nourishment activities, also has similar impacts. Recently, the Service improved

sea turtle protection provisions in Florida; these provisions now require tilling, when needed, to be

above the primary wrack line, not within it.

Disease

Neither the final listing rule nor the recovery plans state that disease is an issue for the species, and no

plan assigns recovery actions to this threat factor. Based on information available to date, West Nile

virus and avian influenza are a minor threat to piping plovers (Service 2009).

Predation

The impact of predation on migrating or wintering piping plovers remains largely undocumented.

Except for one incident reported in 2007 by the New York Times involving a cat in Texas, no

depredation of piping plovers during winter or migration has been noted, although it would be difficult

to document. Avian and mammalian predators are common throughout the species wintering range.

Predatory birds are relatively common during fall and spring migration, and it is possible that raptors

occasionally take piping plovers (Drake et al. 2001). It has been noted, however, that the behavioral

response of crouching when in the presence of avian predators may minimize avian predation on

piping plovers (Morrier and McNeil 1991; Drake 1999a; Drake et al. 2001).

The 1996 Atlantic Coast Recovery Plan summarized evidence that human activities affect types,

numbers, and activity patterns of some predators, thereby exacerbating natural predation on breeding

piping plovers. Nonbreeding piping plovers may reap some collateral benefits from predator

management conducted for the primary benefit of other species. In 1997, the USDA implemented a

public lands predator control partnership in northwest Florida that included the Department of Defense,

National Park Service (NPS), the State of Florida (state park lands) and Service (National Wildlife

Refuges and Ecological Services). The program continues with all partners except Florida  in 2008,

lack of funding precluded inclusion of Florida state lands (although Florida Department of

Environmental Protection staff conduct occasional predator trapping on state lands, trapping is not

implemented consistently).

The NPS and individual state park staff in North Carolina participate in predator control programs

(Rabon 2009 pers. communication). The Service issued permit conditions for raccoon eradication to

Indian River County staff in Florida as part of a coastal Habitat Conservation Plan (Adams 2009 pers.

communication). Destruction of turtle nests by dogs or coyotes in the Indian River area justified the

need to amend the permit to include an education program targeting dog owners regarding the

appropriate means to reduce impacts to coastal species caused by their pets. The Service partnered

with Texas Audubon and the Coastal Bend Bays and Estuaries Program in Texas to implement

predator control efforts on colonial waterbird nesting islands (Cobb 2009 pers. communication). Some

of these predator control programs may provide very limited protection to piping plovers, should they

use these areas for roosting or foraging. Table 6 summarizes predator control actions on a state-bystate basis. The Service is not aware of any current predator control programs targeting protection of

coastal species in Georgia, Alabama, Mississippi, or Louisiana.


TBBSR biological opinion| Page 26

Regarding predation, the magnitude of this threat to nonbreeding piping plovers remains unknown, but

given the pervasive, persistent, and serious impacts of predation on other coastal reliant species, it

remains a potential threat. Focused research to confirm impacts as well as to ascertain effectiveness of

predator control programs may be warranted, especially in areas frequented by Great Lakes birds

during migration and wintering months. We consider predator control on their wintering and

migration grounds to be a low priority at this time.5

Table 6. Summary of predator control programs that may benefit piping plovers on winter and

migration grounds.

State Entities with Predator Control Programs

North Carolina State Parks, Cape Lookout and Cape Hatteras National Seashores.

South Carolina As needed throughout the state, targets raccoons and coyotes.

Georgia No programs known.

Florida

Merritt Island NWR, Cape Canaveral AFS, Indian River County, Eglin AFB, Gulf

Islands NS, northwest Florida state parks (up until 2008), St. Vincent NWR,

Tyndall AFB.

Alabama Late 1990s Gulf State Park and Orange Beach for beach mice, no current

programs known.

Mississippi No programs known.

Louisiana No programs known; sporadic predator control by LDWF on islands with colonial

nesting bird rookeries.

Texas Aransas NWR (hog control for habitat protection), Audubon (mammalian predator

control on colonial waterbird islands that have occasional piping plover use).

Recreational disturbance

Disturbance (i.e., human and pet presence that alters bird behavior) disrupts piping plovers as well as

other shorebird species. Shorebirds are also more likely to flush from the presence of dogs than

people, and birds react to dogs from farther distances than people (Lafferty 2001a, 2001b; Thomas et

al. 2002). Dogs off leash are more likely to flush piping plovers from farther distances than are dogs

on leash; nonetheless, dogs both on and off leashes disturb piping plovers (Hoopes 1993). Pedestrians

walking with dogs often go through flocks of foraging and roosting shorebirds; some even encourage

their dogs to chase birds.

Shorebirds that are repeatedly flushed in response to disturbance expend energy on costly short flights

(Nudds and Bryant 2000); such energy is needed for migration and subsequent reproduction. Intense

human disturbance in shorebird winter habitat can be functionally equivalent to habitat loss if the

disturbance prevents birds from using an area (Goss-Custard et al. 1996), which can lead to roost

abandonment and local population declines (Burton et al. 1996). Pfister et al. (1992) implicate

anthropogenic disturbance as a factor in the long-term decline of migrating shorebirds at staging areas.

Elliott and Teas (1996) found a significant difference in actions between piping plovers encountering

pedestrians and those not encountering pedestrians. Piping plovers encountering pedestrians spend

------------------------------------------------------

5 The threat of direct predation should be distinguished from the threat of disturbance to roosting and feeding piping plovers posed by dogs off leash.


TBBSR biological opinion| Page 27

proportionately more time in non-foraging behavior. This study suggests that interactions with

pedestrians on beaches cause birds to shift their activities from calorie acquisition to calorie

expenditure. Disturbance can cause shorebirds to spend less time roosting or foraging and more time

in alert postures or fleeing from the disturbances (Johnson and Baldassarre 1988; Burger 1991; Burger

1994; Elliott and Teas 1996; Lafferty 2001a, 2001b; Thomas et al. 2002), which limits the local

abundance of piping plovers (Zonick and Ryan 1996; Zonick 2000). In wintering and migration sites,

human disturbance continues to decrease the amount of undisturbed habitat and appears to limit local

piping plover abundance (Zonick and Ryan 1996). While piping plover migration patterns and needs

remain poorly understood and occupancy of a particular habitat may involve shorter periods relative to

the wintering season, information about the energetics of avian migration indicates that this might be a

particularly critical time in the species life cycle.

Off-road vehicles (ORVs) can also disrupt the birds normal behavior patterns (Zonick 2000) or can

significantly degrade piping plover habitat (Wheeler 1979). The 1996 Atlantic Coast Recovery Plan

cites tire ruts crushing wrack into the sand, making it unavailable as cover or as foraging substrate

(Hoopes 1993; Goldin 1993). The plan also notes that the magnitude of the threat from ORVs is

particularly significant, because vehicles extend impacts to remote stretches of beach where human

disturbance will otherwise be very slight. Godfrey et al. (1980 as cited in Lamont et al. 1997)

postulated that vehicular traffic along the beach may compact the substrate and kill marine

invertebrates that are food for the piping plover. Zonick (2000) found that the density of ORVs

negatively correlated with abundance of roosting piping plovers on the ocean beach. Cohen et al.

(2008a) found that radio-tagged piping plovers using ocean beach habitat at Oregon Inlet in North

Carolina were far less likely to use the north side of the inlet where ORV use is allowed, and

recommended controlled management experiments to determine if recreational disturbance drives roost

site selection. Ninety-six percent of piping plover detections was on the south side of the inlet even

though it was farther away from foraging sites (1.8 km from the sound side foraging site to the north

side of the inlet versus 0.4 km from the sound side foraging site to the north side of the inlet) (Cohen et

al. 2008a).

Based on surveys with land managers and biologists, knowledge of local site conditions, and other

information, we have estimated the levels of eight types of disturbance at sites in the U.S. with

wintering piping plovers. There are few areas used by wintering piping plovers that are devoid of

human presence, and just under half have leashed and unleashed dog presence (Smith 2007; Lott et al.

2009, Service unpublished data 2009; Maddock and Bimbi unpublished data). Table 7 summarizes the

disturbance analysis results. Data are not available on human disturbance at wintering sites in the

Bahamas, other Caribbean countries, or Mexico.

[This area intentionally left blank.]


TBBSR biological opinion| Page 28

Table 7. Percent of known piping plover winter and migration habitat locations, by state, where

various types of anthropogenic disturbance have been reported.

Percent by State

Disturbance Type AL FL GA LA MS NC SC TX

Pedestrians 67 92 94 25 100 100 88 54

Dogs on leash 67 69 31 25 73 94 25 25

Dogs off leash 67 81 19 25 73 94 66 46

Bikes 0 19 63 25 0 0 28 19

ATVsa 0 35 0 25 0 17 25 30

ORVsb 0 21 0 25 0 50 31 38

Boats 33 65 100 100 0 78 63 44

Kite surfing 0 10 0 0 0 33 0 0

(a) ATV = all terrain vehicle; (b) ORV = off-road vehicle

Although the timing, frequency, and duration of human and dog presence throughout the wintering

range are unknown, studies in Alabama and South Carolina suggest that most disturbances to piping

plovers occurs during periods of warmer weather, which coincides with piping plover migration

(Johnson and Baldassarre 1988; Lott et al. 2009; Maddock et al. 2009). Smith (2007) documents

varying disturbance levels throughout the nonbreeding season at northwest Florida sites.

LeDee (2008) collected survey responses in 2007 from 35 managers (located in seven states) at sites

that were designated as critical habitat for wintering piping plovers. Ownership included federal, state,

and local governmental agencies and non-governmental organizations managing national wildlife

refuges; national, state, county, and municipal parks; state and estuarine research reserves; state

preserves; state wildlife management areas; and other types of managed lands. Of 44 reporting sites,

40 allowed public beach access year-round and four sites were closed to the public. Of the 40 sites that

allow public access, 62 percent of site managers reported greater than 10,000 visitors from September

through March, and 31 percent reported greater than 100,000 visitors. Restrictions on visitor activities

on the beach included automobiles (at 81 percent of sites), all-terrain vehicles (89 percent), and dogs

during the winter season (50 percent). Half of the survey respondents reported funding as a primary

limitation in managing piping plovers and other threatened and endangered species at their sites. Other

limitations included human resource capacity (24 percent), conflicting management priorities (12

percent), and lack of research (3 percent).

Disturbance can be addressed by implementing recreational management techniques such as vehicle

and pet restrictions and symbolic fencing (usually sign posts and string) of roosting and feeding

habitats. In implementing conservation measures, managers need to consider a range of site-specific

factors, including the extent and quality of roosting and feeding habitats and the types and intensity of

recreational use patterns. In addition, educational materials such as informational signs or brochures

can provide valuable information so that the public understands the need for conservation measures.

In summary, although there is some variability among states, disturbance from human beach recreation

and pets poses a moderate to high and escalating threat to migrating and wintering piping plovers.

Systematic review of recreation policy and beach management across the nonbreeding range will assist

in better understanding cumulative impacts. Site-specific analysis and implementation of conservation

measures should be a high priority at piping plover sites that have moderate or high levels of


TBBSR biological opinion| Page 29

disturbance. The Service and state wildlife agencies should increase technical assistance to land

managers to implement management strategies and monitor their effectiveness.

Military Actions

Twelve coastal military bases are located in the Southeast. To date, five bases have consulted with the

Service under section 7 of the Act, on military activities on beaches and baysides that may affect

piping plovers or their habitat (Table 8). Camp Lejeune in North Carolina consulted formally with the

Service in 2002 on troop activities, dune stabilization efforts, and recreational use of Onslow Beach.

The permit conditions require twice-monthly piping plover surveys and use of buffer zones and work

restrictions within buffer zones. Naval Station Mayport in Duval County, Florida, consulted with the

Service on Marine Corps training activities that included beach exercises and use of amphibious

assault vehicles. The area of impact was not considered optimal for piping plovers, and the

consultation was concluded informally. Similar informal consultations have occurred with Tyndall Air

Force Base (Bay County) and Eglin Air Force Base (Okaloosa and Santa Rosa counties) in northwest

Florida. Both consultations dealt with occasional use of motorized equipment on the beaches and

associated baysides. Tyndall Air Force Base has minimal on-the-ground use, and activities, when

conducted, occur on the Gulf of Mexico beach, which is not considered the optimal area for piping

plovers within this region. Eglin Air Force Base conducts bi-monthly surveys for piping plovers, and

habitats consistently documented with piping plover use are posted with avoidance requirements to

minimize direct disturbance from troop activities. A 2001 consultation with the Navy for one-time

training and retraction operations on Peveto Beach, in Cameron Parish, Louisiana, concluded

informally.

Table 8. Military bases that occur within the wintering/migration range of piping plovers and

contain piping plover habitat.

State Coastal Military Bases

North Carolina Camp Lejeune*

South Carolina No coastal beach bases

Georgia Kings Bay Naval Base

Florida Key West Base, Naval Station Mayport*, Cape Canaveral Air Force

Station, Patrick AFB, MacDill AFB, Eglin AFB*, Tyndall AFB*

Alabama No coastal beach bases

Mississippi Keesler AFB

Louisiana No coastal beach bases

Texas Corpus Christi Naval Air Station

* Bases which conduct activities that may affect piping plovers or their habitat.

Overall, project avoidance and minimization actions currently reduce threats from military activities to

wintering and migrating piping plovers to a minimal threat level. However, prior to removal of the

piping plover from protection under the Act, Integrated Resource Management Plans or other

agreements should clarify if and how a change in legal status would affect plover protections.

Contaminants

Contaminants have the potential to cause direct toxicity to individual birds or negatively affect their

invertebrate prey base (Rattner and Ackerson 2008). Depending on the type and degree of contact,


TBBSR biological opinion| Page 30

contaminants can have lethal and sub-lethal effects on birds, including behavioral impairment,

deformities, and impaired reproduction (Rand and Petrocelli 1985; Gilbertson et al. 1991; Hoffman et

al. 1996).

The Great Lakes Recovery Plan states that concentration levels of polychlorinated biphenol (PCB)

detected in Michigan piping plover eggs have the potential to cause reproductive harm. They further

state that analysis of prey available to piping plovers at representative Michigan breeding sites

indicated that breeding areas along the upper Great Lakes region are not likely the major source of

contaminants to this population.

Petroleum products are the contaminants of primary concern, as opportunities exist for petroleum to

pollute intertidal habitats that provide foraging substrate. Impacts to piping plovers from oil spills

have been documented throughout their life cycle (Chapman 1984; Service 1996; Burger 1997;

Massachusetts Audubon 2003; Amirault-Langlais et al. 2007; Amos 2009 pers. communication). This

threat persists due to the high volume of shipping vessels (from which most documented spills have

originated) traveling offshore and within connected bays along the Atlantic Coast and the Gulf of

Mexico. Additional risks exist for leaks or spills from offshore oil rigs, associated undersea pipelines,

and onshore facilities such as petroleum refineries and petrochemical plants. Beach-stranded 55-gallon

barrels and smaller containers, which may fall from moving cargo ships or offshore rigs and are not

uncommon on the Texas coast, contain primarily oil products (gasoline or diesel), as well as other

chemicals such as methanol, paint, organochlorine pesticides, and detergents (Lee 2009 pers.

communication). Federal and state land managers have protective provisions in place to secure and

remove the barrels, thus reducing the likelihood of contamination.

Lightly oiled piping plovers have survived and successfully reproduced (Chapman 1984; AmiraultLanglais et al. 2007; A. Amos pers. comm. 2009). Chapman (1984) noted shifts in habitat use as

piping plovers moved out of spill areas. This behavioral change was believed to be related to the

demonstrated decline in benthic infauna (prey items) in the intertidal zone and may have decreased the

direct impact to the species. To date, no plover mortality has been attributed to oil contamination

outside the breeding grounds, but latent effects would be difficult to prove.

Deepwater Horizon Mississippi Canyon Well #252 Oil Spill

The Deepwater Horizon Mississippi Canyon Well #252 oil spill, which started April 20, 2010,

discharged into the Gulf of Mexico through July 15, 2010. According to government estimates, the

leak released between 100 and 200 million gallons of oil into the Gulf of Mexico due to the Deepwater

Horizon accident. The U.S. Coast Guard (USCG) estimates that more than 50 million gallons of oil

have been removed from the Gulf, or roughly a quarter of the spill amount. Additional impacts to

natural resources may be attributed to the 1.84 million gallons of dispersant that have been applied to

the spill. Approximately 625 miles of Gulf of Mexico shoreline is currently oiled (approximately 360

miles in LA, 105 miles in MS, 66 miles in AL and 94 miles in FL) (July 28, 2010 Joint Information

Center news release http://app.restorethegulf.gov/go/doc/2931/832251). These numbers reflect a daily

snapshot of shoreline currently experiencing impacts from oil; they do not include cumulative impacts

to date, or shoreline that has already been cleaned.

At the time of this documents writing, piping plovers are arriving to the Gulf of Mexico shorelines,

and no oiled piping plovers have yet to be documented from this spill. However, oiling of designated

piping plover critical habitat has been documented. Impacts to the species and its habitat are expected

but their extent remains hard to predict. The USCG, the states, and responsible parties form the


TBBSR biological opinion| Page 31

Unified Command, with advice from federal and state natural resource agencies, initiated protective

measures and clean-up efforts per prepared contingency plans to deal with petroleum and other

hazardous chemical spills for each state's coastline. The contingency plans identify sensitive habitats,

including all federally listed species habitats, which receive a higher priority for response actions.

Those plans allow for immediate habitat protective measures for clean-up activities in response to large

contaminant spills. While such plans usually ameliorate the threat to piping plovers, it is yet unknown

how much improvement will result in this case given the breadth of the impacts associated with the

Deepwater Horizon incident.

Based on all available data prior to the Deepwater Horizon oil spill, the risk of impacts from

contamination to piping plovers and their habitat was recognized, but the safety contingency plans

were considered adequate to alleviate most of these concerns. The Deepwater Horizon incident has

brought heightened awareness of the intensity and extent to fish and wildlife habitat from large-scale

releases. In addition to potential direct habitat degradation from oiling of intertidal habitats and

retraction of stranded boom, impacts to piping plovers may occur from the increased human

disturbance associated with boom deployment and retraction, clean-up activities, wildlife response, and

damage assessment crews working along affected shorelines. Research studies are being initiated to

begin documenting the potential expanse of impacts to the piping plover.

Pesticides

In 2000, mortality of large numbers of wading birds and shorebirds, including one piping plover, at

Audubons Rookery Bay Sanctuary on Marco Island, Florida, occurred following the countys aerial

application of the organophosphate pesticide Fenthion for mosquito control purposes (Williams 2001).

Fenthion, a known toxin to birds, was registered for use as an avicide by Bayer, a chemical

manufacturer. Subsequent to a lawsuit being filed against the Environmental Protection Agency (EPA)

in 2002, the manufacturer withdrew Fenthion from the market, and EPA declared all uses of the

chemical were to end by November 30, 2004 (American Bird Conservancy 2007). All other counties

in the U.S. now use less toxic chemicals for mosquito control. It is unknown whether pesticides are a

threat for piping plovers wintering in the Bahamas, other Caribbean countries, or Mexico.

Climate Change (sea-level rise)

Over the past 100 years, the globally averaged sea level has risen approximately 10 to 25 centimeters

(cm) (Rahmstorf et al. 2007), a rate that is an order of magnitude greater than that seen in the past

several thousand years (Douglas et al. 2001 as cited in Hopkinson et al. 2008). The IPCC suggests that

by 2080 sea-level rise could convert as much as 33 percent of the worlds coastal wetlands to open

water (IPCC 2007). Although rapid changes in sea level are predicted, estimated time frames and

resulting water levels vary due to the uncertainty about global temperature projections and the rate of

ice sheets melting and slipping into the ocean (IPCC 2007; CCSP 2008).

Potential effects of sea-level rise on coastal beaches may vary regionally due to subsidence or uplift as

well as the geological character of the coast and nearshore (CCSP 2009; Galbraith et al. 2002). In the

last century, for example, sea-level rise along the U.S. Gulf Coast exceeded the global average by 13 to

15 cm, because coastal lands west of Florida are subsiding (EPA 2009). Sediment compaction and oil

and gas extraction compound tectonic subsidence (Penland and Ramsey 1990; Morton et al. 2003;

Hopkinson et al. 2008). Low elevations and proximity to the coast make all nonbreeding coastal

piping plover foraging and roosting habitats vulnerable to the effects of rising sea level. Furthermore,

areas with small astronomical tidal ranges (e.g., portions of the Gulf Coast where intertidal range is


TBBSR biological opinion| Page 32

less than 1 meter) are the most vulnerable to loss of intertidal wetlands and flats induced by sea-level

rise (EPA 2009). Sea-level rise was cited as a contributing factor in the 68 percent decline in tidal flats

and algal mats in the Corpus Christi area (i.e., Lamar Peninsula to Encinal Peninsula) in Texas

between the 1950s and 2004 (Tremblay et al. 2008). Mapping by Titus and Richman (2001) showed

that more than 80 percent of the lowest land along the Atlantic and Gulf coasts was in Louisiana,

Florida, Texas, and North Carolina, where 73.5 percent of all wintering piping plovers were tallied

during the 2006 IPPC (Elliott-Smith et al. 2009).

Inundation of piping plover habitat by rising seas could lead to permanent loss of habitat if natural

coastal dynamics are impeded by numerous structures or roads, especially if those shorelines are also

armored with hardened structures. Without development or armoring, low undeveloped islands can

migrate toward the mainland, pushed by the over-washing of sand eroding from the seaward side and

being re-deposited in the bay (Scavia et al. 2002). Overwash and sand migration are impeded on

developed portions of islands. Instead, as sea-level increases, the ocean-facing beach erodes and the

resulting sand is deposited offshore. The buildings and the sand dunes then prevent sand from washing

back toward the lagoons, and the lagoon side becomes increasingly submerged during extreme high

tides (Scavia et al. 2002), diminishing both barrier beach shorebird habitat and protection for mainland

developments.

Modeling for three sea-level rise scenarios (reflecting variable projections of global temperature rise)

at five important U.S. shorebird staging and wintering sites predicted loss of 20 to 70 percent of

current intertidal foraging habitat (Galbraith et al. 2002). These authors estimated probabilistic sealevel changes for specific sites partially based on historical rates of sea-level change (from tide gauges

at or near each site); they then superimposed this on projected 50 percent and 5 percent probability of

global sea-level changes by 2100 of 34 cm and 77 cm, respectively. The 50 percent and 5 percent

probability sea level change projections were based on assumed global temperature increases of 2° C

(50 percent probability) and 4.7° C (5 percent probability). The most severe losses were projected at

sites where the coastline is unable to move inland due to steep topography or seawalls. The Galbraith

et al. (2002) Gulf Coast study site at Bolivar Flats, Texas, is a designated critical habitat unit known to

host high numbers of piping plovers during migration and throughout the winter (e.g., 275 individuals

were tallied during the 2006 IPPC) (Elliott-Smith et al. 2009). Under the 50 percent likelihood

scenario for sea-level rise, Galbraith et al. (2002) projected approximately 38 percent loss of intertidal

flats at Bolivar Flats by 2050; however, after initially losing habitat, the area of tidal flat habitat was

predicted to slightly increase by the year 2100, because Bolivar Flats lacks armoring, and the coastline

at this site can thus migrate inland. Although habitat losses in some areas are likely to be offset by

gains in other locations, Galbraith et al. (2002) noted that time lags may exert serious adverse effects

on shorebird populations. Furthermore, even if piping plovers are able to move their wintering

locations in response to accelerated habitat changes, there could be adverse effects on the birds

survival rates or reproductive fitness.

Table 9 displays the potential for adjacent development and/or hardened shorelines to impede response

of habitat to sea-level rise in the eight states supporting wintering piping plovers. Although complete

linear shoreline estimates are not readily obtainable, almost all known piping plover wintering sites in

the U.S. were surveyed during the 2006 IPPC. To estimate effects at the census sites, as well as

additional areas where piping plovers have been found outside of the census period, Service biologists

reviewed satellite imagery and spoke with other biologists familiar with the sites. Of 406 sites, 204

(50 percent) have adjacent structures that may prevent the creation of new habitat if existing habitat

were to become inundated. These threats will be perpetuated in places where damaged structures are

repaired and replaced, and exacerbated where the height and strength of structures are increased. Data


TBBSR biological opinion| Page 33

do not exist on the amount or types of hardened structures at wintering sites in the Bahamas, other

Caribbean countries, or Mexico.

Table 9. Number of sites surveyed during the 2006 winter IPPC with hardened or developed

structures adjacent to the shoreline. Those marked with an asterisk (*) are additional sites that

were not surveyed in the 2006 IPPC.

State

Number of sites

surveyed during the

2006 winter Census

Number of sites

with some armoring

or development

Percent of

sites affected

North Carolina 37 (+2)* 20 51

South Carolina 39 18 46

Georgia 13 2 15

Florida 188 114 61

Alabama 4 (+2)* 3 50

Mississippi 16 7 44

Louisiana 25 (+2)* 9 33

Texas 78 31 40

Overall Total 406 204 50

Sea-level rise poses a significant threat to all piping plover populations during the migration and

wintering portion of their life cycle. Ongoing coastal stabilization activities may strongly influence the

effects of sea-level rise on piping plover habitat. In Louisiana, Federal and State agencies take into

account the effects of sea-level rise and attempt to compensate for those effects in the design of coastal

restoration projects. Improved understanding of how sea-level rise will affect the quality and quantity

of habitat for migrating and wintering piping plovers remains an urgent need.

Storm events

Although coastal piping plover habitats are storm-created and maintained, the 1996 Atlantic Coast

Recovery Plan also notes that storms and severe cold weather may take a toll on piping plovers, and

the 2003 Great Lakes Recovery Plan postulates that loss of habitats, such as overwash passes or wrack,

where birds shelter during harsh weather, poses a threat. Storms are a component of the natural

processes that form coastal habitats used by migrating and wintering piping plovers, and positive

effects of storm-induced overwash and vegetation removal have been noted in portions of the

wintering range. For example, Gulf Islands National Seashore habitats in Florida benefited from

increased washover events that created optimal habitat conditions during the 2004 and 2005 hurricane

seasons, with biologists reporting piping plover use of these habitats within six months of the storms

(Nicholas 2005 pers. communication). Hurricane Katrina (2005) over-washed the mainland beaches of

Mississippi, creating many tidal flats where piping plovers were subsequently observed (Winstead

2008). Hurricane Katrina also created a new inlet and improved habitat conditions on some areas of

Dauphin Island, Alabama (LeBlanc 2009 pers. communication). Conversely, localized storms, since

Katrina, have induced habitat losses on Dauphin Island (LeBlanc 2009 pers. communication).

Noel and Chandler (2005) suspect that changes in habitat caused by multiple hurricanes along the

Georgia coastline altered the spatial distribution of piping plovers and may have contributed to winter

mortality of three Great Lakes piping plovers. Following Hurricane Ike in 2008, Arvin (2009) reported

decreased numbers of piping plovers at some heavily eroded Texas beaches in the center of the storm


TBBSR biological opinion| Page 34

impact area and increases in plover numbers at sites about 100 miles to the southwest. However,

piping plovers were observed later in the season using tidal lagoons and pools that Ike created behind

the eroded beaches (Arvin 2009).

The adverse effects on piping plovers attributed to storms are sometimes due to a combination of

storms and other environmental changes or human use patterns. For example, four hurricanes between

2002 and 2005 are often cited in reference to rapid erosion of the Chandeleur Islands, a chain of lowlying islands in Louisiana where the 1991 IPPC tallied more than 350 piping plovers. Comparison of

imagery taken three years before and several days after Hurricane Katrina indicated that the

Chandeleur Islands lost 82 percent of their surface area (Sallenger et al. 2009), and a review of aerial

photography prior to the 2006 IPPC suggested little piping plover habitat remained (Elliott-Smith et al.

2009). However, Sallenger et al. (2009) noted that habitat changes in the Chandeleur Islands stem not

only from the effects of these storms but rather from the combined effects of the storms, long-term

(i.e., greater than 1,000 years) diminishing sand supply, and sea-level rise relative to the land.

Sallenger et al. (2009) went on to explain that although the marsh platform of the Chandeleur Islands

continued to erode for 22 months post-Katrina, some sand was released from the marsh sediments

which in turn created beaches, spits, and welded swash bars that advanced the shoreline seaward.

Thus, although intense erosional forces have affected the Chandeleur Islands, they are still providing

high quality shorebird habitat in the form of sand flats, spits, and beaches, until they are eroded below

sea level.

Other storm-induced adverse effects include post-storm acceleration of human activities such as beach

nourishment, sand scraping, and berm and seawall construction. Such stabilization activities can result

in the loss and degradation of feeding and resting habitats. Storms also can cause widespread

deposition of debris along beaches. Removal of debris often requires large machinery, which can

cause extensive disturbance and adversely affect habitat elements such as wrack. Another example of

indirect adverse effects linked to a storm event is the increased access to Pelican Island (LeBlanc 2009

pers. communication) due to merging with Dauphin Island following a 2007 storm (Gibson et al.

2009).

Recent climate change studies indicate a trend toward increasing hurricane numbers and intensity

(Emanuel 2005; Webster et al. 2005). When combined with predicted effects of sea-level rise, there

may be increased cumulative impacts from future storms. Storms can create or enhance piping plover

habitat while causing localized losses elsewhere in the wintering and migration range. Available

information suggests that some birds may have resiliency to storms and move to unaffected areas

without harm, while other reports suggest birds may perish from storm events. Significant concerns

include disturbance to piping plovers and habitats during cleanup of debris and post-storm acceleration

of shoreline stabilization activities, which can cause persistent habitat degradation and loss.

Threats Summary

Habitat loss and degradation on winter and migration grounds from shoreline and inlet stabilization

efforts, both within and outside of designated critical habitat, remain a serious threat to all piping

plover populations. Modeling strongly suggests that the population is very sensitive to adult and

juvenile survival. Therefore, while there is a great deal of effort extended to improve breeding success

and thus improve and maintain a higher population over time, it is also necessary to ensure that the

wintering habitat, where birds spend most of their time, is secure. On some of the wintering grounds,

the shoreline areas used by wintering piping plovers are being developed, stabilized, or otherwise

altered, generally making the habitat unsuitable. Even in areas where habitat conditions are


TBBSR biological opinion| Page 35

appropriate, human disturbance on beaches may negatively impact piping plovers energy budget, as

they may spend more time being vigilant and less time in foraging and roosting behavior. In many

cases, the disturbance is severe enough that piping plovers appear to avoid some areas altogether.

Threats on the wintering grounds may impact piping plovers breeding success if they start migration

or arrive at the breeding grounds with a poor body condition.

Analysis of the species/critical habitat likely to be affected

The proposed action has the potential to adversely affect wintering piping plovers and their habitat,

including designated critical habitat in Units LA-4 and LA-5, within the action area. The construction

activities may lead to temporarily diminished quantity and quality of intertidal foraging and roosting

habitats within the project area and action area, resulting in decreased survivorship of migrating and

wintering plovers (potential effects on breeding success from poor body condition) and temporary

adverse affects to critical habitat. The length of construction (which varies from 16.6 months to 4

years) may delay the recovery of benthic species due to the prolonged disturbance of the benthic fauna.

Ultimately, the project goal is to restore the diversity of coastal barrier island habitats, but the

temporary effects of construction will require time for natural recovery and would extend beyond one

wintering season. The detailed effects of the proposed action on piping plovers and critical habitat will

be considered further in the remaining sections of this opinion.

ENVIRONMENTAL BASELINE

Louisianas loss of wetlands and barrier islands to open water is now a well-documented fact in

numerous studies. Since the 1930s Louisiana has lost 1,900 square miles of land (this includes coastal

wetlands). From 1990 to 2000, approximately 24 square miles of coastal land were lost each year.

The 2004 Louisiana Coastal Area Ecosystem Restoration Study projected that 513 square miles of land

would disappear by 2050, including a gain of 161 square miles from CWPPRA projects (Corps 2004).

In Louisiana, barrier island and barrier headland erosion is attributable to increasing tidal prism,

insufficient volumes of sediment supplied by littoral currents, land subsidence, and sea-level rise

(Boesch 1982). Although increases in the tidal prism may be primarily responsible for enlargement of

tidal passes, the insufficient supply of sand available to rebuild eroded areas has also contributed to

increased tidal pass widths and shoreline retreat (Louisiana Coastal Wetlands Conservation and

Restoration Task Force and the Wetlands Conservation and Restoration Authority 1999). Where

insufficient supplies of sand prevail, measures to maximize sand retention, such as sand fencing and

vegetative planting, are used to effectively rebuild and maintain such eroded areas.

Louisiana barrier islands are part of a complex and dynamic coastal system that continually respond to

tidal passes, tides, wind, waves, erosion and deposition, long-shore sediment transport and depletion,

fluctuations in sea level, and weather events. During storm events, overwash across the barrier islands

is common, depositing sediments on the bayside, clearing vegetation and increasing the amount of

open, sand flat habitat ideal for shoreline dependent shorebirds. The locations and shapes of the

islands perpetually adjust to these physical forces. Winds move sediment across the dry beaches

forming low dunes and the island interior landscape. The natural communities contain plants and

animals that are subject to shoreline erosion and deposition, salt spray, wind, drought conditions, and

sandy soils. Vegetative communities include fore dunes, occasional primary dunes, salt marsh, and

black mangroves.

The TBBSR project area consists of undeveloped barrier islands (Raccoon, Whiskey, Trinity, and

Timbalier) that are protected and managed by the LDWF. Human access to the barrier island system is


TBBSR biological opinion| Page 36

by boat only and direct access on the islands requires a LDWF permit. Occasional disturbance directly

on the islands results from IPPC surveys (once every 5 years), breeding bird surveys (annual), winter

and summer bird atlas surveys (annual), and banded bird surveys (occasional). Regular boat traffic

adjacent to the islands occurs as a result of ongoing recreational and commercial fishing activity,

recreational birding, and nearshore and offshore oil and gas activities. As indicated in Table 10 several

CWPPRA projects have also been constructed on portions of the islands to restore and maintain the

diverse functions of those barrier island habitats. As a result of those projects, the added sediment has

been reworked by the dynamic coastal processes of the barrier island system and has resulted in the

preservation and maintenance of shorebird and waterbird foraging and nesting habitats.

Table 10. CWPPRA projects that have been constructed on barrier islands within the Terrebonne

Basin.

Project

(CWPPRA Project No.)

Federal

Agencya

Construction

Completed Net Benefit

Isles Dernieres Restoration

East Island (TE-20) EPA 1999 9 acres

Vegetative Plantings 

Timbalier Island

Demonstration (TE-17)

NRCS 1996 N/Ab

Isles Dernieres Restoration

Trinity Island (TE-24) EPA 1999 109 acres

Whiskey Island

Restoration (TE-27) EPA 2000 1,239 acres

Raccoon Island Breakwaters

Demonstration (TE-29) NRCS 1997 N/A

Timbalier Island Dune and

Marsh Creation (TE-40) EPA 2005 273 acres

New Cut Dune and Marsh

Creation (TE-37) EPA 2007 102 acres

Raccoon Island Shoreline

Protection and Marsh Creation

(TE-48)

NRCS

Breakwaters2006;

Marsh Creation not

yet constructed

71 acres

Ship Shoal: Whiskey West

Flank Restoration (TE-47) EPA Engineering &Design Phase 195 acres

Whiskey Island

Back Barrier Marsh Creation

(TE-50)

EPA

Dredging

completed 2009;

Planting scheduled

for summer 2010

316 acres

(a) EPA = Environmental Protection Agency; NMFS = National Marine Fisheries Service; NRCS = Natural Resources

Conservation Service; (b) N/A = Not applicable.

Status of the species within the action area

The number of piping plovers within the action area during winter is difficult to assess because the

number of birds utilizing the area varies from year to year and throughout the wintering season.

Because the islands are only accessible by boat and because winter weather generally provides

inclement weather conditions, daily surveys over any length of time during the wintering season are

also difficult to coordinate. Consequently, surveys for non-breeding (e.g., over-wintering and


TBBSR biological opinion| Page 37

migrating) plovers within the action area have been sporadic at best (Table 11). Because the 2005

hurricane season severely damaged much of the piping plover critical habitat across the state, the

Service provided funding to the LDWF to conduct hurricane impact assessments of piping plovers and

their habitat across the Louisiana coast. The LDWF conducted annual, one-day-count piping plover

surveys between January 1 and February 18 from 2007 through 2010. Due to lack of manpower and

inclement weather (e.g., dangerous boating conditions) LDWF was unable to survey the Isles

Dernieres and Timbalier Islands in 2010. For surveys that have been successful, results indicate that

piping plovers utilize any non-vegetated or sparsely vegetated portions of the subject barrier islands.

Such habitat consists of sand beaches, spits, and flats, mud flats, shell beaches, and oyster reefs

associated with both the Gulf- and bay-sides of the island, as well as wash-over areas created by storm

events.

Table 11. Piping plover numbers from sporadic survey results within the action area. The 2010

LDWF survey data are not included here since the subject islands were not surveyed in that year.

Location

1991

IPPCa

Survey

1996

IPPC

Survey

2001

IPPC

Survey

2006

IPPC

Survey

2006/2007

CWSb

Survey

2007

LDWFc

Survey

2008

LDWF

Survey

2009

LDWF

Survey

Raccoon

Island 43 0 32 39 49 18 53 NSd

Trinity/East

Island 86 83e 73 16 11f 20 NS 4

Whiskey

Island NS 22 40 31 48 3 36 NS

Timbalier

Island 89 84 78 17 NS 14 39 47

(a) IPPC = International Piping Plover Census; (b) CWS = Canadian Wildlife Service; (c) LDWF = Louisiana Department of Wildlife

and Fisheries-Natural Heritage Program; (d) NS = Not Surveyed; (e) The value includes counts for both Trinity and East Islands

which were surveyed separately during this census year; (f) The value includes East Island only.

Although piping plover numbers fluctuate from survey to survey, Table 11 appears to indicate an

overall trend of decreasing piping plover numbers on Trinity and Timbalier Islands over the last 9

surveys. Prior to the 2001 IPPC survey, Trinity and East Islands were two separate islands, and East

Island was roughly a large sand flat with very little marsh. According to 2001 satellite imagery, the

channel (known as New Cut) between the two islands began to fill in through long-shore transport of

sediment, and by 2002, New Cut had naturally filled in to reconnect the two islands. In 2007, a

CWPPRA project (TE-37) was completed to restore dune habitat to the naturally created sand flat and

provided a bayside marsh platform behind the New Cut area, in order to further tie the two islands

together. Meanwhile, suitable habitat on the easternmost end of East Island has continued to erode.

Suitable habitat on Timbalier Island appears to be affected by erosion as well. For the surveys

conducted in 1991, 1996, and 2001, all of the birds observed were concentrated on a sand spit at the

eastern tip of the island. After review of aerial photography from 1998, 2004, 2005, 2008, and 2009,

the large sand spit on the eastern tip of Timbalier Island has eroded below sea level. Although we do

not know for certain why survey trends are showing a decrease in piping plover numbers for Trinity

and Timbalier Islands, review of aerial photography indicate that erosion has caused changes in the

availability of suitable habitat on those islands.

All of the islands within the action area are designated critical habitat for the piping plover. Raccoon,

Trinity, East, and Whiskey Islands are located within Unit LA-4, while Timbalier Island is located in


TBBSR biological opinion| Page 38

Unit LA-5. The Final Determinations of Critical Habitat for Wintering Piping Plovers (Service 2001b)

describes critical habitat within those units as . . . the entire islands where primary constituent

elements occur to the MLLW [mean low low water]. At the time of designation, Raccoon,

Trinity/East, Whiskey, and Timbalier Islands consisted of an estimated 3,681 acres of barrier island

habitat, a portion of which consisted of sparsely vegetated and non-vegetated areas suitable for piping

plovers (based upon 1998 aerial photography). Within the proposed project footprints the Corps

estimates that approximately 1,315 acres of suitable piping plover habitat currently exist on the islands

(Figure 8) based on 2008 aerial photography and excluding densely vegetated areas (e.g., mangroves

and saline marsh). An additional 272 acres currently exists on East Island located outside of the

project footprint for Trinity Island Plan C but still within the action area.

Table 12. Existing critical habitat acreages within the project footprint for each island of the NER

Plan as estimated from 2008 aerial photography. The Corps did not include East Island in these

estimates because East Island is not within the project footprint for the Trinity Island plan.

ISLAND

CRITICAL

HABITAT

(acres)

Raccoon Island 171

Whiskey Island 269

Trinity Island 303

Timbalier Island 572

Total NER Plan 1,315

Factors affecting species environment within the action area

As mentioned previously, the project-area islands remain undeveloped and are relatively isolated from

the mainland. Raccoon, Whiskey, and Trinity/East Islands are afforded protection from major

disturbance activities as part of the LDWFs Isles Dernieres Barrier Islands Wildlife Refuge.

Occasional bird surveying and bird and wetland research are allowed on the islands via LDWF

permits, while both recreational birding and commercial and recreational fishing occur along the

islands perimeters. Other than nearby boat traffic from fishing and offshore oil and gas activities, the

islands generally do not receive regular visitors. There is one oil and gas platform located offshore of

the northeastern end of East Island; however, there is no direct access to the island from that facility.

Timbalier Island is mostly owned by the State but several small patches of privately owned marsh

persist. There are several existing active oil and gas leases on the island including multiple access

canals, and the State also leases two camps on/near the island. Thus, Timbalier Island experiences

somewhat regular human disturbance related to oil and gas wells, pipeline maintenance, and boat

traffic.

Mammalian predators (e.g., raccoons, coyotes) have access to all of the islands; however, they do not

appear to permanently inhabit the islands. Mammalian predators swim back and forth to the islands

from the mainland or adjacent islands, but none of the islands provide enough shelter or forage to

sustain a constant predator population, and somewhat regular storm events (e.g., flooding) tend to

discourage mammals from persisting on the islands. Avian predators may also be present throughout

the year but likely peak during fall and spring migration periods.


TBBSR biological opinion| Page 39

The Deepwater Horizon Mississippi Canyon Well #252 oil spill, which started April 20, 2010,

discharged into the Gulf of Mexico through July 15, 2010. The LDWF confirmed the presence of oil

on the project-area islands on or about May 20, 2010. Shoreline Cleanup Assessment Team (SCAT)

reports throughout the duration of the spill documented various degrees of oiling on each of the islands

(Table 13). At the time this document is being written, oil spill response efforts are ongoing in the

form of continued SCAT surveys, Stage III cleanup efforts, and Natural Resources Damage and

Assessment Restoration (NRDAR) surveys and data collection.

At this time, it is unknown if there are any current or lasting affects to the inter-tidal invertebrate food

source used by piping plovers from either oil or oil dispersants and resulting cleanup activities within

the action area. A greater impact to the piping plover and its habitat might be the increased human

disturbance activities associated with cleanup, wildlife response, and damage assessment crews highly

visible on the shorelines and ongoing surveys.

Table 13. Results of the SCAT reports for the Deepwater Horizon Mississippi Canyon Well #252

oil spill and follow-up cleanup activities on Isles Dernieres and Timbalier Island.

Location Extent of Oil Cleanup Actions

Proposed or Implemented

Raccoon Island Oiled vegetation on bayside; tar balls on beach Manual cleanup with shovels;

removal of oiled wrack

Whiskey Island Large tar balls, mousse, tar mats on beach; oiled

vegetation on bayside

Manual cleanup with shovels;

removal of oiled wrack

Trinity/East

Island

Oil, tar balls, tar patties, tar mats on beach; tar

patties and mats extending into vegetation on

eastern end

Manual cleanup with shovels;

removal of oiled wrack

Timbalier Island Oil, mousse, tar balls and patties on beach; oil on

vegetation on bayside

Manual cleanup with shovels;

removal of oiled wrack

EFFECTS OF THE ACTION

The proposed action includes marsh creation and dune and beach restoration of four barrier islands.

The proposed project intends to lengthen and widen each island in order to add much-needed sediment

to the barrier island system, prolong the existence of the islands, and restore barrier island habitat,

function, and morphology. Much of the proposed project would occur in habitat that is used regularly

by piping plovers and designated as critical habitat for the species. Construction of the fully proposed

NER Plan will overlap with multiple piping plover wintering seasons, while construction of only the

TSP (i.e., Whiskey Island Plan C) will overlap with two wintering seasons. Short-term and temporary

construction impacts to piping plovers will occur when the birds are roosting and feeding in the area.

The deposition of sand and marsh material will temporarily deplete the intertidal food base along the

Gulf beach and bay-side flats, respectively, and temporarily disturb roosting birds during project

construction on the islands. The shaping and grading of the newly created beach and dune will

temporarily disturb any wrack that has accumulated on the Gulf-side of the island. This also affects

feeding and roosting habitat for piping plovers, since they often use wrack for cover and foraging. The

construction of the marsh creation area will cover any existing bay-side flats used by foraging plovers

and will render that area unusable until natural processes re-work the sediments, overwash areas and

bay-side flats are again created by tidal and storm events, and benthic prey species re-colonize those

areas. Similar effects to the beach and dune portions of the islands will occur again on the Gulf-side of


TBBSR biological opinion| Page 40

the islands during renourishment periods (see project plan descriptions on pages 2 through 4 for target

years) and extend for 2 years beyond the renourishment period until the benthic fauna recovers. The

temporary increase in human presence and construction activity on the islands may also disturb piping

plovers from utilizing adjacent areas outside of the project footprints, such as nearby sand spits and

East Island (not included in the Trinity Island Plan C portion of the action).

The geomorphic characteristics of barrier islands, dunes, overwash fans, and inlets are critical to a

variety of natural resources and influence a barrier islands ability to respond to wave action, including

storm overwash and sediment transport. The protection or persistence of these important natural

processes and wildlife resources are part of the goal of this restoration project. The newly created

beach, dune, and marsh will not impede overwash but may temporarily consist of less than optimal

roosting and foraging habitat until natural wrack is restored, the benthic prey base is able to recover

from the construction activities, and overwash areas are again created by natural tidal and weather

events. The newly added sediment will be reworked by natural wind and wave processes which will,

given time, create sand spits and flats on the ends and bay-sides of the islands, or as sediment is lost

from one island, it will be carried by long-shore transport to another island. Thus, piping plover

foraging, roosting, and critical habitat will continue to be lost and created through the natural processes

associated with daily tidal events and future storm events.

Factors to be considered

Proximity of the action

Lack of regular surveys and fluctuation of use by piping plovers from year to year make it difficult to

measure the number of birds actually using any particular island (Gulf- or bay-side) within the action

area. We expect direct short-term effects in the form of: (1) disturbance during sediment placement,

dune construction, marsh creation, and vegetative planting; and (2) a temporary loss of food base

within the project footprint on each island for up to 2 years following completion of sediment

placement until the benthic community re-colonizes the project area. The footprints of each island

plan occur within critical habitat Units LA-4 and LA-5. East Island (i.e., the eastern portion of Trinity

Island; see Figure 1) would not be included within any project footprint and would provide available

habitat during project construction. However, human presence/activity within the project footprint on

Trinity Island may potentially disturb birds foraging or roosting on East Island due to the proximity of

the project footprint.

Distribution

The Corps proposes project construction activities on the Gulf- and bay-sides of Raccoon, Whiskey,

Trinity, and Timbalier Islands within Terrebonne Parish. We expect direct effects to wintering piping

plovers along existing sand beaches, spits, and flats, mud flats, shell beaches, oyster reefs, and

washover areas associated with both the Gulf- and bay-sides of the islands as a result of human activity

and ground disturbance on the islands. Similar temporary disturbance would occur again during a

renourishment cycle on the Gulf-side of the island only.

Timing

Construction of the NER Plan will overlap with multiple piping plover wintering/migrating seasons

(mid-July to late April), while construction of only the TSP (i.e., Whiskey Island Plan C) will overlap

with two wintering/migrating seasons.


TBBSR biological opinion| Page 41

Nature of the effect

The effects to piping plover may be direct, indirect, and short-term. We anticipate a temporary (i.e., up

to 2 years post-construction) decrease in benthic prey species within existing piping plover habitat as a

result of sand and marsh material placement on the four islands. A decrease in survival of birds on

migrating or wintering grounds due to lack of optimal habitat contribute to decreased survival rates,

decreased productivity on the breeding grounds, and therefore increased vulnerability to any of the

three piping plover populations. We expect concurrent short-term impacts from human disturbance

during project construction to both the bird and its habitat. Activities that impact or alter the use of

optimal habitat or increase disturbance to the species may decrease the survival and recovery potential

of the piping plover.

The effects to critical habitat Units LA-4 and LA-5 are activities that impact or alter the PCEs

(disturbance to the species) which may decrease the survival and recovery potential of the piping

plover. Such effects consists of temporary reductions in the value of the units from disturbance to

foraging and roosting piping plovers due to human activity during construction, a temporary decrease

in benthic prey species due to sand and marsh material placement, and vegetative planting of newly

created dune and marsh areas. In addition, existing washover areas would be covered by placement of

new material until natural coastal processes (e.g., daily tidal events, storm events, etc.) are allowed to

re-work the additional sediment to create new sand and mud flats.

Duration

For the NER Plan, construction would be completed in approximately 4 years, while the TSP-only

option would require 16.6 months for construction. The activities associated with construction of the

marsh creation are a one-time occurrence for each island. Construction of the dune and beach would

initially occur at TY1 for each island; however, one renourishment event would occur for Raccoon (at

TY30), Trinity (at TY25), and Timbalier (at TY30) Islands and two renourishment events (at TY20

and TY40) would occur for Whiskey Island. Each activity may vary in duration for each island

depending on the amount of work needed, weather conditions, and equipment mobilization and

maintenance. The Corps anticipates beginning construction on the TSP (i.e., Whiskey Island Plan C)

in June 2012; construction of the remaining islands would occur later in time as additional

authorizations are approved. We do not expect long-term, permanent alteration of the natural coastal

processes and the renourishment events would result in a pulse effect that would temporarily disturb

the Gulf-side of each island while the bay-side of each island would remain untouched after initial

construction. The addition of sand and marsh material on critical habitat Units LA-4 and LA-5 is

expected to decrease the quality of foraging habitat from 6 months up to 2 years until the intertidal

benthic fauna recovers to normal population levels on each island.

Disturbance frequency, intensity, and severity

We expect short-term disturbance from construction activities and short-term effects of sand and marsh

material placement. Direct effects to critical habitat Units LA-4 and LA-5 would include temporary

smothering of intertidal benthic prey species at TY1 (on both sides of the islands) and again at the

target year of a renourishment cycle (only on the Gulf-side of the islands). We anticipate construction

activities to have short-term and temporary effects on piping plover populations. We anticipate that

piping plovers located within the construction area would move outside of the construction zone due to

disturbance. We anticipate that the intertidal benthic fauna would recover within 2 years of each


TBBSR biological opinion| Page 42

disturbance event. We do not anticipate any permanent adverse changes to barrier island morphology

because initial construction elevations and follow-up renourishment elevations would not prevent

island washover during storm events and the created marsh platform would allow for natural island

retreat or rollover. There would not be any increased or continual disturbance within critical habitat

Units LA-4 and LA-5 as a result of the project. Over the long-term the additional sediment would

allow for creation of piping plover habitat on the islands as natural processes re-work the sediment to

create sand flats, mud flats, and sand spits.

Analysis for the effects of the action

Direct effects

Direct effects are those direct or immediate effects of a project on the species or its habitat. The

construction window (i.e., disposal of sand and marsh material) will extend through several piping

plover migration and wintering seasons for the proposed NER Plan and two piping plover migration

and wintering seasons for the TSP. Heavy machinery and equipment (e.g., ORVs and bulldozers

operating on project area beaches and bay-side sand and mud flats, the placement of the dredge

pipeline along the beach, and sand and marsh material disposal) may adversely affect migrating and

wintering piping plovers in the project area by disturbance and disruption of normal activities such as

roosting and feeding, and possibly forcing birds to expend valuable energy reserves to seek available

habitat elsewhere.

Burial and suffocation of invertebrate intertidal prey species will occur during sand and marsh material

placement and follow-up renourishment events. Impacts will affect the project footprint on each island

as well as some down-drift areas. Timeframes projected for benthic recruitment and re-establishment

following sand and marsh material placement are from 6 months up to 2 years. Due to the duration of

project construction and depending on actual recovery rates, impacts will occur even if renourishment

events occur outside the plover migration and wintering seasons.

Direct effects to critical habitat Units LA-4 and LA-5 consist of sand and marsh material placement

over existing habitat areas on the Gulf- and bay-sides of the islands at TY1 and along the Gulf-side of

the islands for follow-up renourishment at different target years, temporary loss of washover areas,

vegetative plantings, and burial and suffocation of intertidal benthic prey species.

Indirect effects

Indirect effects are those that are caused by or result from the proposed action, are later in time, and are

reasonably certain to occur. Reducing the potential for the formation of optimal habitats (such as

overwash or ephemeral pool formations) is a possible indirect effect. The piping plovers rapid

response (within 6 months) to habitats formed by washover areas demonstrates the importance of

overwash created sand and mud flats for wintering and migrating piping plovers. Implementation of

the proposed project will temporarily cover existing overwash habitat on the islands. However, given

time, the intertidal zone along the islands will re-establish and with daily tidal processes and occasional

storm events natural overwash and ephemeral pool habitat would again be recreated on the islands.

Thus, the indirect effect will not be permanent for the life of the project.

The project life and expected future re-nourishment activities do not increase the likelihood of longterm increased human disturbance or that the LDWF or other entities would initiate construction of

new infrastructure or upgrade existing facilities, such as camps or oil and gas infrastructure within or


TBBSR biological opinion| Page 43

adjacent to the project area. The LDWF is committed to managing and maintaining the islands as a

wildlife refuge area and improving shorebird nesting, roosting, and foraging habitats within minimal

human disturbance.

Beneficial effects

Beneficial effects are wholly positive without any adverse effects. We expect the prolonged existence

and creation of foraging and roosting habitat for piping plovers within critical habitat Units LA-4 and

LA-5 as an overall result of the proposed TBBSR project. The additional sediment (within the

sediment-starved system) would be re-worked by natural processes to allow for island rollover as

well as the formation of optimal piping plover habitat in the form of sand flats, mud flats, and sand

spits. The Corps has estimated that without the project there would be no piping plover critical habitat

remaining on the islands at TY50, but with the project, Raccoon Island would retain 133 acres of

critical habitat, Whiskey Island would retain 118 acres, Trinity Island would retain 87 acres (does not

include East Island), and Timbalier Island would retain 227 acres (Corps 2010).

Species response to the proposed action

This biological opinion is based on direct and indirect effects that are anticipated to piping plovers

(wintering and migrating) and designated critical habitat as a result of restoring beach, dune, and marsh

on four barrier islands and concurrent temporary disruption of existing plover foraging and roosting

habitat for the long-term benefit of maintaining existing barrier island habitat. In the context of

migrating and wintering piping plovers, it is anticipated that an unquantifiable number of piping

plovers utilizing the four barrier islands and up to 1,315 acres of existing critical habitat will be

impacted by (1) construction disturbance within the action area, and (2) temporary habitat loss within

the project footprint on each island for the duration of construction activities (4 years for the NER Plan

and 16.6 months for the TSP) and up to 2 years post construction for the recovery of intertidal benthic

prey species.

The Service anticipates temporary adverse affects to piping plovers and their critical habitat throughout

the action area from increased human activity during construction. The nearest suitable habitats into

which piping plovers can disperse are located on Wine Island (located between Trinity/East and

Timbalier Islands, see Figure 1) and East Timbalier Island (located 6.5 miles east of Timbalier Island).

The next closest suitable habitat areas consist of West Belle Pass (part of critical habitat Unit LA-5) to

the east and the eastern shoreline of Point au Fer Island (critical habitat Unit LA-3) to the west; both of

which are greater than 10 miles away from the action area. However, all of those areas have been

impacted by the Deepwater Horizon oil spill, and foraging and roosting habitat in those areas are

recovering from ongoing oil spill cleanup activities and NRDAR surveys and data collection. The

duration of disturbance and effects to piping plovers from the oil spill are ongoing for an unknown

period of time.

The closest non-oiled impacted habitat would be the Atchafalaya River Delta which is located greater

than 30 miles west of the action area. Critical habitat Unit LA-2 consists of the deltaic splay and the

dredge disposal islands occurring east and southeast of the main navigation channel of the Atchafalaya

River. At this time, there have been no reported impacts to those areas as a result of the oil spill.

Table 14 depicts the results of sporadic winter surveys of the Atchafalaya River Delta over the last 19

years.


TBBSR biological opinion| Page 44

Table 14. Piping plover numbers from winter surveys within the Atchafalaya River Delta.

Location

1991

IPPCa

Survey

1996

IPPC

Survey

2001

IPPC

Survey

2006

IPPC

Survey

2006/2007

CWSb

Survey

2007

LDWFc

Survey

2008

LDWF

Survey

2009

LDWF

Survey

2010

LDWF

Survey

Atchafalaya

River Delta 27 0 21 6 NSd NS 27 0 NS

(a) IPPC = International Piping Plover Census; (b) CWS = Canadian Wildlife Service; (c) LDWF = Louisiana Department of Wildlife

and Fisheries-Natural Heritage Program; (d) NS = Not Surveyed.

The Service has documented that critical habitat within the action area has been oiled and is

experiencing ongoing disturbance by oil spill cleanup activities; such disturbance will continue for an

unknown period of time. The proposed action would also involve anywhere from 16.6 months to 4

years of disturbance activities for the construction period, plus an additional 2 years of recovery for the

intertidal benthic community following TY1. However, it is possible that the proposed action would

ameliorate some effects associated with the oil spill by providing for maintenance of the existing

habitat and creation of new habitat in the future as sediments are re-worked by wind and wave action.

In addition, the project would not result in permanent changes to the natural processes that maintain

the PCEs of critical habitat. Daily tidal processes and occasional storm events would also re-work the

additional sediment to recreate overwash areas, sand and mud flats, and sand spits. Without the

additional sediment from the project, critical habitat on the subject islands would eventually erode

below sea level.

Although restoration of the four barrier islands would follow on the heels of the Deepwater Horizon oil

spill and would result in temporary disturbance within the action area, in time the proposed action

would ultimately benefit the piping plover and its critical habitat by restoring diverse barrier island

habitats used by the piping plover. The proposed action would also allow for the continued existence

and creation of habitat within critical habitat Units LA-4 and LA-5 throughout the project life.

CUMULATIVE EFFECTS

The proposed project would occur on State-owned lands and/or water bottoms, except for a few small

areas of marsh on Timbalier Island which are privately owned. Cumulative effects include the effects

of future State, tribal, local, or private actions that are reasonably certain to occur in the action area

considered in this biological opinion. Future Federal actions that are unrelated to the proposed action

are not considered in this section because they require separate consultation pursuant to section 7 of the

Act.

It is unknown how much influence the proposed project would contribute to the recreational use of the

barrier islands; regardless, the LDWF restricts human access to the islands throughout the year.

Overall recreational use of the islands is restricted to nearby birding and fishing, and because of their

remoteness, there is little human disturbance on the islands. Any future proposed actions that are

within endangered or threatened species habitat will require section 7 or 10 permitting from the

Service to be covered under the Act.

Impacts to the action area from the Deepwater Horizon Mississippi Canyon Well #252 oil spill

includes Stage III cleanup actions for weathered oil, tar balls, tar mats, tar patties, oil mousse, oiled

wrack, ongoing NRDAR surveys and studies, dispersants in the water, and increased human

disturbance from those cleanup and monitoring activities. The final breadth of the oil spill impacts to


TBBSR biological opinion| Page 45

the shoreline and shoreline-dependent species remains unknown; however, at the conclusion of the

emergency event, section 7 consultation will be completed with the lead Federal agency, the U.S.

Coast Guard.

CONCLUSION

After reviewing the current status of the piping plover wintering population of the northern Great

Plains, the Great Lakes, and the Atlantic Coast; the environmental baseline for the action area; the

effects of the proposed TBBSR project; and cumulative effects, it is the Services biological opinion

that implementation of the TBBSR project, as proposed, is not likely to jeopardize the continued

existence of non-breeding piping plover. As noted previously, the overall status of the listed species is

stable, if not increasing.

The survival and recovery of all breeding populations of piping plovers are fundamentally dependent

on the continued availability of sufficient habitat in their coastal migration and wintering range, where

the species spends more than two-thirds of its annual cycle. All piping plover populations are

inherently vulnerable to even small declines in their most sensitive vital rates (i.e., survival of adults

and fledged juveniles). Mark-recapture analysis of resightings of uniquely banded piping plovers from

seven breeding areas by Roche et al. (2009) found that apparent adult survival declined in four

populations and increased in none over the life of the studies. Some evidence of correlation in year-toyear fluctuations in annual survival of Great Lakes and eastern Canada populations, both of which

winter primarily along the southeastern U.S. Atlantic Coast, suggests that shared over-wintering and/or

migration habitats may influence annual variation in survival. Further concurrent mark-resighting

analysis of color-banded individuals across piping plover breeding populations has the potential to

shed light on threats that affect survival in the migration and wintering range. Progress towards

recovery (which is attained primarily through intensive protections to increase productivity on the

breeding grounds) would be quickly slowed or reversed by even small sustained decreases in survival

rates during migration and wintering.

Critical Habitat

Critical habitat for this species has been designated within the project area and the action area. This

biological opinion does not rely on the regulatory definition of destruction or adverse modification

of critical habitat in 50 Code of Federal Regulations (C.F.R.) 402.02. Instead, it relies upon the

statutory provisions of the Act to complete the following analysis with respect to critical habitat.

The proposed project has been designed to mimic natural barrier island habitat and, in the long-term,

would aid natural processes in creating and maintaining the PCEs of critical habitat by providing

sediment within the sediment-starved barrier island system. The amount of critical habitat in Units

LA-4 and LA-5 directly affected from the project is approximately 1,315 acres of sparsely and nonvegetated barrier island habitat. The project area would be temporarily disturbed during construction

activities which would impede piping plovers attempting to roost and forage in the area during the

migration and wintering months that coincide with construction. Temporary disturbance to 1,315 acres

of Units LA-4 and LA-5 equates to 5.3 percent of designated critical habitat in Louisiana and 0.76

percent of all designated critical habitat throughout the Southeast (i.e., North Carolina to Texas).

Because the effects to critical habitat would be temporary in nature and the overall project would be

beneficial in the long-term, it is the Services biological opinion that implementation of the TBBSR

project is not likely to destroy or adversely modify designated critical habitat Units LA-4 and LA-5.


TBBSR biological opinion| Page 46

INCIDENTAL TAKE STATEMENT

Section 9 of the Act and Federal regulation pursuant to section 4(d) of the Act prohibit the take of

endangered and threatened species, respectively, without special exemption. Take is defined as to

harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect, or to attempt to engage in any

such conduct. Harm is further defined by the Service to include significant habitat modification or

degradation that results in death or injury to listed species by significantly impairing essential

behavioral patterns, including breeding, feeding, or sheltering. Harass is defined by the Service as

intentional or negligent actions that create the likelihood of injury to listed species to such an extent as

to significantly disrupt normal behavior patterns which include, but are not limited to, breeding,

feeding, or sheltering. Incidental take is defined as take that is incidental to, and not the purpose of,

the carrying out of an otherwise lawful activity. Under the terms of section 7(b)(4) and section 7(o)(2),

taking that is incidental to and not intended as part of the agency action is not considered to be

prohibited taking under the Act provided that such taking is in compliance with the terms and

conditions of this Incidental Take Statement.

The measures described below are non-discretionary, and must be undertaken by the Corps so that they

become binding conditions of any contract, grant, or permit issued to the Corps contractor, as

appropriate, for the exemption in section 7(o)(2) to apply. The Corps has a continuing duty to regulate

the activity covered by this incidental take statement. If the Corps (1) fails to assume and implement

the terms and conditions or (2) fails to require its contractor to adhere to the terms and conditions of

the incidental take statement through enforceable terms that are added to the contract, grant, or permit

document, the protective coverage of section 7(o)(2) may lapse. In order to monitor the impact of

incidental take, the Corps and/or its contractor must report the progress of the action and its impact on

the species to the Service as specified in the incidental take statement. [50 CFR §402.14(I) (3)]

AMOUNT OR EXTENT OF TAKE ANTICIPATED

The Service anticipates incidental take of piping plovers will be difficult to detect because: (1)

harassment to the level of harm (e.g., poor body condition due to loss of foraging opportunities) may

only be apparent on the breeding grounds or during migration the following year; (2) movement and

use of habitat by individual piping plovers or disturbance to individual birds would be difficult to

quantify as birds may move in, out, or through the action area during winter months; and (3) loss of

individual birds may be masked by fluctuations in piping plover numbers within the action area

between wintering seasons. However, the level of take of this species can be anticipated by the

temporary effects to the PCEs within 1,315 acres of designated critical habitat because:

1. Piping plovers winter in the action area.

2. The initial effects of project activities would occur over multiple migration and wintering

seasons until construction is complete.

3. Temporarily increased levels of human disturbance are expected for the duration of

construction activities.

4. A temporary reduction of food base will occur due to sand and marsh material placement.

That temporary reduction in benthic prey species can last anywhere from 6 months to 2

years.

The Service has reviewed the biological information and other information relevant to the proposed

action. The take is expected in the form of harm and harassment because of: (1) temporary decreased

fitness and survivorship of wintering plovers; and (2) temporary decreased fitness and survivorship of


TBBSR biological opinion| Page 47

plovers attempting to migrate to breeding grounds, due to temporary loss of and disturbance to

foraging and roosting habitat. Incidental take covers take of the species within the action area.

Consultation must be reinitiated if one or more of the following conditions occur:

1. The Corps expands the project scope outside of the described action area (e.g., restoration of

Wine or East Timbalier Islands), or adds additional project features (e.g., rock breakwaters)

that create effects to the species or its critical habitat that are not already considered in this

biological opinion.

2. Monitoring indicates that piping plovers fail to reoccupy the project footprint within 2 years

post construction (i.e., TY3).

3. Monitoring indicates that the benthic fauna within the project footprint do not recover to

baseline conditions by 2 years post construction (i.e., TY3).

Table 15. How the incidental take will be monitored if the specific number of individuals cannot

be determined. This will be based on the best available commercial and scientific information.

Species Critical Habitat Habitat Conditions and Quality

Piping Plover 1,315 acres

1. Prior to initiating construction activities, the

project footprints on each island would be

delineated using a GPSa unit.

2. Piping plover usage of the project area would

be monitored during and for 2 years post

construction (i.e., TY3).

3. Monitoring of benthic fauna should indicate

recovery to baseline conditions within the project

footprint by 2 years post construction (i.e., TY3).

(a) GPS = global positioning system.

EFFECT OF THE TAKE

In the accompanying biological opinion, the Service determined that this level of anticipated take is not

likely to result in jeopardy to the piping plover species or destruction or adverse modification of its

critical habitat. Incidental take of piping plovers is anticipated to occur within 1,315 acres of barrier

island habitat on Raccoon, Whiskey, Trinity/East, and Timbalier Islands during project construction

and up to 2 years following construction until the intertidal benthic community recovers.

REASONABLE AND PRUDENT MEASURES

The Service believes the following reasonable and prudent measures (RPMs) are necessary and

appropriate to minimize take on non-breeding piping plovers during implementation of the proposed

TBBSR project within the action area.

1. A baseline piping plover survey shall be conducted within the migrating and wintering season

immediately prior to initial construction within the action area. As part of that survey, the

project footprint should be delineated using a global position system (GPS) unit and

appropriately marked/flagged for future survey reference and data collection.

2. A survey of the intertidal benthic prey species community shall be conducted within the

migrating and wintering season immediately prior to initial construction, at the same time as


TBBSR biological opinion| Page 48

the plover distribution surveys, in order to establish a baseline of benthic prey species diversity

and abundance.

3. Piping plover monitoring surveys shall be conducted during the migrating and wintering

seasons throughout initial project construction and three consecutive years following

completion of initial construction.

4. To confirm re-establishment of suitable foraging habitat for migrating and wintering plovers,

monitoring surveys of the intertidal benthic prey species community shall be conducted each

year following completion of initial construction for three consecutive years, preferably at the

same time as the bird surveys.

5. The Service shall be notified in writing at least 3 months prior to a renourishment event for

each island. If renourishment events are conducted during the migrating and wintering season,

piping plover monitoring surveys shall be conducted for the duration of construction activities

following the survey schedule outlined in Appendix B.

6. A comprehensive report describing the actions taken to implement the RPMs and terms and

conditions associated with this incidental take statement (including data sheets from surveys

conducted) shall be submitted to the Service by June 1 of the year following completion of all

required surveys.

TERMS AND CONDITIONS

In order to be exempt from the prohibitions of section 9 of the Act, the Corps shall execute the

following terms and conditions, which implement the RPMs, described above and outline required

reporting/monitoring requirements. These terms and conditions are non-discretionary.

Monitoring Requirements

1. Requirements for piping plover surveys

a) A survey schedule (with dates) is listed in Appendix B and the recommendation is for at

least 3 survey dates per month; this schedule should be followed as closely as possible. If

conditions require a deviation from the recommended survey schedule, such information

should be carefully documented, including an explanation why any deviation from the

recommended schedule was deemed necessary. The Service recognizes that given the

remoteness of the project area and the potential for inclement weather conditions during the

plover wintering season, three survey dates per month may be difficult to achieve in

Louisiana. Therefore, the Service will require a minimum of two survey dates per month.

b) Piping plover identification, especially when in non-breeding plumage, can be difficult.

Qualified professionals with shorebird/habitat survey experience must conduct the required

survey work. Piping plover monitors must be capable of detecting and recording locations

of roosting and foraging plovers, and documenting observations in legible, complete field

notes. Aptitude for monitoring includes keen powers of observation, familiarity with avian

biology and behavior, experience observing birds or other wildlife for sustained periods,

tolerance for adverse weather, experience in data collection and management, and patience.

c) Binoculars, a GPS unit, a 10-60x spotting scope with a tripod, and the Service datasheet

(Appendix B) must be used to conduct the surveys.

d) Negative (i.e., no plovers seen) and positive survey data shall be recorded and reported.

e) Piping plover locations shall be recorded with a GPS unit set to record in decimal degrees

in universal transverse mercator (UTM) North American Datum 1983 (NAD83).


TBBSR biological opinion| Page 49

f) Habitat, landscape, and substrate features used by piping plovers when seen shall be

recorded. Such features are outlined on the Service data sheet in Appendix B.

g) Behavior of piping plovers (e.g., foraging, roosting, preening, bathing, flying, aggression,

walking) shall be documented on the Service data sheet in Appendix B.

h) Color-bands seen on piping plovers shall also be carefully documented, and should also be

reported according to the information found at the following websites. Information

regarding color-band observations can be found at:

http://www.fishwild.vt.edu/piping_plover/Protocols_final_draft.pdf,

http://www.waterbirds.umn.edu/Piping_Plovers/piping2.htm, and

http://www.fws.gov/northeast/pipingplover/pdf/BahamasBandReporting2010.pdf.

2. Requirements for surveying benthic prey species

a) A qualified professional with sediment/macroinvertebrate sampling experience must

conduct the required benthic prey species surveys.

b) A baseline macroinvertebrate survey will be conducted at the same time of the initial piping

plover survey during the migrating/wintering season immediately prior to construction.

Additional surveys will be conducted during the migrating/wintering season each year postconstruction for three consecutive years to determine benthic prey species recovery. Such

surveys shall be conducted at the same time as the plover surveys.

c) Sampling will be conducted using a basic before and after control and impact design

method. Sampling will be coordinated with piping plover foraging observations based on

low tide surveys.

d) In addition to recording benthic species abundance and diversity, a qualitative measure of

sediment characteristics (sand, shell, mud) will also be recorded.

e) A detailed sampling methodology shall be developed in coordination with the Service and

LDWF prior to initiating surveys.

Reporting Requirements

1. Incorporate all data collected into an appropriate database, preferably one for piping plovers

and one for benthic prey species.

2. Annual update reports shall be provided to the Service and LDWF by June 30 of each calendar

year once construction begins. Annual update reports should include data sheets, maps, a copy

of the database, and the progress and initial findings of piping plover and benthic community

surveys, as well as any problematic issues that may hinder future survey efforts.

3. If the Corps foresees any problematic issues that would require a change in the recommended

survey schedule due to work conditions or project delays, the Corps should immediately notify

the Service so that we can resolve/correct any such issues.

4. A final comprehensive report should be provided to the Service and LDWF by June 30

following the third year of surveys. That final report should include an analysis of all data

results from the piping plover and benthic community surveys.

5. At least six months prior to mobilization, the Corps should notify the Service in writing prior to

each proposed renourishment event. That notification should include whether there are any

changes in the proposed amount of renourishment per island.

Upon locating a dead or injured piping plover that may have been harmed or destroyed as a direct or

indirect result of the proposed project, the Corps and/or contractor shall be responsible for notifying

the Services Lafayette, Louisiana, Field Office (337/291-3100) and the LDWFs Natural Heritage


TBBSR biological opinion| Page 50

Program (225/765-2821). Care shall be taken in handling an injured piping plover to ensure effective

treatment or disposition and in handling dead specimens to preserve biological materials in the best

possible state for later analysis.

COORDINATION OF INCIDENTAL TAKE STATEMENT WITH OTHER LAWS,

REGULATIONS, AND POLICIES

Migratory Bird Treaty Act (MBTA)

The MBTA implements various treaties and conventions between the U.S., Canada, Japan, Mexico,

and the former Soviet Union for the protection of migratory bird. Under the provisions of the MBTA

it is unlawful by any means or manner to pursue, hunt, take, capture or kill any migratory bird except

as permitted by regulations issued by the Fish and Wildlife Service. The term take is not defined in

the MBTA, but the Service has defined it by regulation to mean to pursue, hunt, shoot, wound, kill,

trap, capture or collect any migratory bird, or any part, nest or egg or any migratory bird covered by

the conventions or to attempt those activities.

In order to comply with the MBTA and potential for this project to impact nesting shorebirds, the

Corps should follow the Service and LDWFs standard guidelines (Appendix D) to protect against

impacts to nesting shorebirds during implementation of this project.

The Fish and Wildlife Service will not refer the incidental take of piping plovers for prosecution under

the Migratory Bird Treaty Act of 1918, as amended (16 U.S.C. 703-712), if such take is in compliance

with the terms and conditions specified here.

CONSERVATION RECOMMENDATIONS

Section 7(a)(1) of the Act directs Federal agencies to utilize their authorities to further the purposes of

the Act by carrying out conservation programs for the benefit of endangered and threatened species.

Conservation recommendations are discretionary agency activities to minimize or avoid adverse

effects of a proposed action on listed species or critical habitat, to help implement recovery plans, or to

develop information.

1. The Corps should consider retro-fitting all sand fencing poles with pointy tops or caps to

reduce avian predation.

2. As an alternative to installing sand fencing for the TBBSR and future restoration projects, the

Corps should evaluate the feasibility of promoting natural dune growth with planting native

dune grasses.

3. We encourage the Corps to take a proactive approach via application of their Section 7(a)(1)

responsibilities, which would further minimize the issues surrounding the cumulative impacts

to listed species resulting from implementation of coastal restoration projects in Louisiana.

4. We encourage the Corps to continue to coordinate with the Service and LDWF during the preplanning phases of future restoration projects (including any sand placement projects) within

piping plover designated critical habitat.



TBBSR biological opinion| Page 52

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Corps of Engineers.


APPENDIX A

FIGURES


TBBSR biological opinion | Page A-1

Figure 1. The proposed National Ecosystem Restoration Plan would encompass the Isles Dernieres Barrier Islands and Timbalier

Island in Terrebonne Parish, Louisiana (Corps 2010).


TBBSR biological opinion | Page A-2

Figure 2. The proposed Raccoon Island Plan E with Terminal Groin would encompass all of Raccoon Island except for a portion of

the western sand spit (Corps 2010).


TBBSR biological opinion | Page A-3

Figure 3. The proposed Whiskey Island Plan C would encompass only portions of Whiskey Island in order to avoid a previous marsh

creation area (TE-50) and existing mangrove habitat (Corps 2010).


TBBSR biological opinion | Page A-4

Figure 4. The Trinity Island Plan C would encompass most of Trinity Island while avoiding New Cut and East Island (Corps 2010).


TBBSR biological opinion | Page A-5

Figure 5. The Timbalier Island Plan E would encompass all of Timbalier Island (Corps 2010).


TBBSR biological opinion | Page A-6

Figure 6. Distribution and range of piping plovers (base map from Haig and Elliott-Smith 2004).

Conceptual presentation of subspecies and distinct population segments (DPS) ranges

are not intended to convey precise boundaries.


TBBSR biological opinion | Page A-7

Figure 7. Breeding population distribution* in the wintering/migration range (from GrattoTrevor et al. 2009, reproduced by permission).

*Regions: ATLC=Atlantic (eastern) Canada; ATLS=Atlantic U.S.; GFS=Gulf Coast of southern Florida; GFN=Gulf Coast of

north Florida; AL=Alabama; MS/LA=Mississippi and Louisiana; TXN=northern Texas; and TXS=southern Texas. For each

breeding population, circles represent the percentage of individuals reported wintering along the eastern coast of the U.S. from

the central Atlantic to southern Texas/Mexico up to December 2008. Each individual was counted only once. Grey circles

represent Eastern Canada birds, orange circles for U.S. Great Lakes, green circles for the U.S. Great Plains, and black circles for

Prairie Canada. The relative size of the circle represents the percentage from a specific breeding area seen in that winter region.

Total number of individuals observed on the wintering grounds was 46 for Eastern Canada, 150 for the U.S. Great Lakes, 169 for

the U.S. Great Plains, and 356 for Prairie Canada.


TBBSR biological opinion | Page A-8

Figure 8. Approximate extent of critical habitat that currently exists on Raccoon, Whiskey, Trinity, and Timbalier Islands. Recentrestoration (i.e., CWPPRA) projects are also depicted for Raccoon and Whiskey Islands (Corps 2010).

Raccoon Island Whiskey Island

Trinity Island Timbalier Island


APPENDIX B

Non-breeding Piping Plover Survey Guidelines


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page B-1

Louisiana Piping Plover Non-Breeding Season Survey Guidelines

The purpose of these guidelines is to assess and/or monitor piping plover use of coastal

restoration features related to the Terrebonne Basin Barrier Shoreline Restoration Project.

Survey locations should include the coastal restoration features plus adjacent suitable shorebird

habitat (i.e., intertidal beaches, mud flats, sand flats, algal flats, wash-over passes, and associated

dunes and flats above annual high tide). Monitoring should be conducted July 15 through May

15 to follow the International Shorebird Survey (ISS) census dates listed below. The ISS

schedule usually results in three surveys per month. If this is not feasible, try to do at least two

surveys per month on the ISS census dates. Surveys should be conducted on ISS dates plus or

minus two days. For example, a survey scheduled for the 15th could be conducted on any day

between the 13th through the 17th of that month.

Spring Migration Fall Migration Winter

February 25 July 15 October 15

March 5 July 25 October 25

March 25 August 5 November 5

April 5 August 15 November 15

April 15 August 25 November 25

April 25 September 5 December 5

May 5 September 15 December 15

May 15 September 25 December 25

October 5 January 5

January 15

January 25

February 5

February 15

To the extent possible, surveys should be conducted when birds are foraging. The best time is at

low tide, but surveys can also be conducted on a falling or rising tide provided that the foraging

areas are not completely covered. During high tide, birds will be roosting. Although piping

plovers often roost near foraging areas, the birds will be more difficult to locate. Avoid

conducting surveys during poor weather conditions (e.g., high winds, rain).

Methods

In most cases surveys will be conducted by foot. All terrain vehicles (ATVs) may be used to

expedite the transport of observers over long stretches of liner routes (leapfrogging teams

down a beach in 0.5 to 1 mile increments), but all bird counting will be conducted while walking.

[Driving on vegetated areas shall not be permitted. Any ATV use should be coordinated

with the Louisiana Department of Wildlife and Fisheries Isles Dernieres Wildlife Refuge

management staff.] Birds on exposed mudflats that may be inaccessible by foot should be

counted from boats. Each survey crew should use their best professional judgment on the most

efficient way to conduct the survey and should document in detail if any deviations to these

guidelines are deemed necessary.


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page B-2

Observers should work in teams of two to four people, depending on the width of the beach and

beach/tidal interface. Wide coastal beaches will require a greater number of observers in order to

assure that birds are not missed on the back (aft) side of the dune. Observers working on

beaches that contain moderate to high dunes should climb them every 0.5 to 1 mile and look for

wash-over flats and pools that may not be visible from the beach. Coastal islands will be

surveyed on both the Gulf and bay sides (this may require multiple teams of observers in order to

finish the surveys in a timely manner).

Piping plover locations will be recorded with global positioning system (GPS) units. GPS

locations will be recorded in universal transverse mercator (UTM) map datum NAD 83 CONUS.

Each survey team should carry aerial photography of the survey route so that new breaks (cuts)

in the beach or island can be noted on the survey maps. Habitat data will also be collected and

will include foraging substrate, portion of the beach used and side of the island on which the

birds are found (see attached data sheet). These habitat criteria have been adapted from the 2006

International Winter Piping Plover Census organized by the U.S. Geological Survey. Behavioral

data (e.g., foraging, roosting, preening, bathing, flying, aggression, walking) of piping plovers

when seen should also be documented.

Negative data is as important as positive data. Indicate when surveys have been done and no

birds were observed. Although piping plovers are the target species, any additional observations

of other species would help the U.S. Fish and Wildlife Service to identify shorebird

concentration areas and management needs.


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page B-3

Louisiana Piping Plover Survey Form

(Note: Most criteria adopted from the 2006 Wintering Piping Plover Census Form)

A. Total # Piping Plovers Observed: _______________________________________________

B. Location Description (Name): __________________________________________________

1. Parish: _________________________________________________________________

2. UTM location NAD 83 CONUS (center):

Northing_____________________________ Easting____________________________

3. Land Ownership:

___Federal ___State ___Municipal ___Private ___County ___Tribal

C. Date of survey:_________________ Time survey conducted: __________to __________

D. Weather Conditions:

1. Tide stage(s): ___Low ___Mid ___High (___Rising / ___Falling)

2. General weather: ___Sunny ___Partly cloudy ___Overcast ___Rain ___Fog

___Other (describe):_______________________________________________________

3. Approximate temperature: ________Celsius / Fahrenheit (circle one)

4. Wind speed: _____miles/hr Wind direction:_________

E. Description of Habitat Surveyed (check as many as apply). The Code designation will be

used in Section F table below:

Body of Water Type:

____I. Ocean ____II. Protected bay, harbor, cove, lagoon ____III. Gulf of Mexico

____IV. Ocean Inlet ____V. Other (describe)__________________________________

Shoreline Type:

____A. Mainland ____B. Barrier Island ____C. Spoil Island ____D. Bar

____E. Other Island ____F. Washover area ____G. Other (describe)______________

Specific Description:

____1. Sand beach ____2. Sand spit ____3. Sand flat ____4. Sand bar

____5. Salt flat ____6. Gravel shore ____7. Oyster reef ____8. Mudflat

____9. Vegetation (algal) mat ____10. Vegetated shoreline

____11. Other (describe)___________________________________________________

Location Description (criteria for islands only):

____ i. Gulf-side of island ____ii. Bay-side of island

____a. Tidal interface ____b. Fore dune ____c. Top of dune ____d. Aft dune


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page B-4

F. Numbers, behaviors, habitat types, and GPS location(s) of piping plovers observed (mark on

map if possible).

Number of

Plovers

Observed

Behavior

Displayed

(e.g., foraging, roosting,

preening, walking,

flying, aggression, etc.)

Habitat Type

where Plovers

were found

(use designations from

Section E above,

e.g., IIC8ii, IIIB9ia)

UTM location NAD 83 CONUS

Northing Easting

G. Mode(s) of transportation:

____Foot ____Car/Truck ____ATV ____Boat ____Airboat ____Other__________

H. Habitat (shoreline) covered: _______miles (please calculate using aerial photographs scale)

I. Observers: __________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

J. Additional comments or notes:___________________________________________________

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page B-5

K. Additional species encountered (for flying flocks lump as peeps and estimate number).

Species of special interest are listed below; please add any additional species.

OTHER SPECIES TOTAL# OTHER SPECIES TOTAL#

Reddish Egret

Marbled Godwit

Red Knot

Western Sandpiper

Stilt Sandpiper

Short-billed Dowitcher

Snowy Plover

Wilsons Plover

Long-billed Curlew

American Oystercatcher


APPENDIX C

Standard Conditions for In-water Work in the Presence of Manatees


TBBSR biological opinion |Page C-1

Guidelines for Activities in Proximity to Manatees and Their Habitat

A. All personnel associated with the project should be informed of the potential presence of

manatees, manatee speed zones, and the need to avoid collisions with and injury to

manatees. Such personnel instruction should also include a discussion of the civil and

criminal penalties for harming, harassing, or killing manatees, which are protected under

the Marine Mammal Protection Act of 1972 and the Endangered Species Act of 1973.

B. All contract and/or construction personnel are responsible for observing water-related

activities for the presence of manatee(s).

C. Temporary signs should be posted prior to and during all construction/dredging activities

to remind personnel to be observant for manatees during active construction/dredging

operations or within vessel movement zones (i.e., work area), and at least one sign should

be placed where it is visible to the vessel operator.

D. Siltation barriers, if used, should be made of material in which manatees could not

become entangled, and should be properly secured and regularly monitored. Barriers

should not impede manatee movement.

E. If a manatee is sighted within 100 yards of the active work zone, special operating

conditions should be implemented, including: no operation of moving equipment within

50 feet of a manatee; all vessels should operate at no wake/idle speeds within 100 yards

of the work area; and siltation barriers, if used, should be re-secured and monitored.

Once the manatee has left the 100-yard buffer zone around the work area on its own

accord, special operating conditions are no longer necessary, but careful observations

would be resumed.

F. Any manatee sighting should be immediately reported to the U.S. Fish and Wildlife

Services (Service) Lafayette, Louisiana, Field Office (337/291-3100) and the Louisiana

Department of Wildlife and Fisheries (LDWF), Natural Heritage Program (225/765-

2821).


APPENDIX D

Louisiana Guidelines for Minimizing Disturbance to Colonial Nesting Birds


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page D-1

Louisiana Guidelines for Minimizing Disturbance to Colonial Nesting Birds

Nesting colonies may be present that are not currently listed in the database maintained by the

Louisiana Department of Wildlife and Fisheries (LDWF). That database is updated primarily by

monitoring the colony sites that were previously surveyed during the 1980s. Until a new,

comprehensive coast-wide survey is conducted to determine the location of newly-established

nesting colonies, we recommend that a qualified biologist inspect the proposed work site for the

presence of undocumented nesting colonies during the nesting season. In addition, we

recommend that on-site contract personnel be informed of the need to identify colonial nesting

birds and their nests, and should avoid affecting them during the breeding season.

To minimize disturbance to colonial nesting birds, the following restrictions on activity should

be observed:

1. For colonies containing nesting brown pelicans, all activity occurring within 2,000 feet of

a rookery should be restricted to the non-nesting period (i.e., September 15 through

March 31). Nesting periods vary considerably among Louisianas brown pelican

colonies, however, so it is possible that this activity window could be altered based upon

the dynamics of the individual colony. The Louisiana Department of Wildlife and

Fisheries Fur and Refuge Division should be contacted to obtain the most current

information about the nesting chronology of individual brown pelican colonies. Brown

pelicans are known to nest on barrier islands and other coastal islands in St. Bernard,

Plaquemines, Jefferson, Lafourche, and Terrebonne Parishes, and on Rabbit Island in

lower Calcasieu Lake, in Cameron Parish.

2. For colonies containing nesting wading birds (i.e., herons, egrets, night-herons, ibis, and

roseate spoonbills), anhingas, and/or cormorants, all activity occurring within 1,000 feet

of a rookery should be restricted to the non-nesting period (i.e., September 1 through

February 15, exact dates may vary within this window depending on species present).

3. For colonies containing nesting gulls, terns, and/or black skimmers, all activity occurring

within 650 feet of a rookery should be restricted to the non-nesting period (i.e.,

September 16 through April 1, exact dates may vary within this window depending on

species present).

Below is a table explaining the nesting chronology of species that are known to nest in

Louisiana. The table is an excerpt from page 31 of:

Martin, R.P., and G.D. Lester. 1990. The Atlas and Census of Wading Bird and Seabird Nesting

Colonies of Louisiana: 1990. Louisiana Department of Wildlife and Fisheries  Louisiana

Natural Heritage Program. Special Publication No. 3 for the U.S. Department of Interior  Fish

and Wildlife Service. Contract No. 14-16-0004-89-963.


U.S. Fish and Wildlife Service

Ecological Services Office

Lafayette, Louisiana

TBBSR biological opinion |Page D-2



APPENDIX B

U.S. FISH AND WILDLIFE SERVICE

COORDINATION REPORT


TERREBONNE BASIN BARRIER

SHORELINE RESTORATION

FINAL FISH AND WILDLIFE

COORDINATION ACT REPORT

September 17, 2010












































A-2

PROJECT INFORMATION SHEET BARRIER ISLAND VALUE ASSESSMENT

Terrebonne Basin Barrier BVA Project Information Sheet

September 2010

Final

Project Name: LCA Terrebonne Basin Barrier Shoreline Restoration

Project Type(s): Barrier island restoration, marsh creation, vegetative planting

Sponsoring Agency: US Army Corps of Engineers

Preparer of information sheet: Karen Soileau, Aaron Bass, Chris Dean, and Ken Duffy.

Information found in this project information sheet was obtained primarily from the

Integrated Feasibility Study and Final Environmental Impact Statement for the

Terrebonne Basin Barrier Shoreline Restoration Study.

Project Area:

The proposed project provides for the restoration of the Timbalier and Isles Dernieres

Barrier Island chains located in Terrebonne and Lafourche Parishes, Louisiana. The

Timbalier Reach is comprised of Timbalier Island and East Timbalier Island. Raccoon,

Whiskey, Trinity, East, and Wine, are the primary islands that comprise the Isles

Dernieres barrier island chain.

Intermediate Array of Alternatives:

Based upon the results of the plan formulation, analyses and screening, twelve (12) plan

alternatives have been recommended for inclusion in the Intermediate Array of

Alternatives. The twelve alternatives were grouped into five (5) categories described

below.

Category 1, Alternative 1 No Action – The No-Action Alternative assumes there would

be no future barrier island restoration within the study area. The barrier islands will

continue to be subjected to the factors and processes that are contributing to the loss of

the Timbalier and Isles Dernieres barrier island chains and will result in a direct loss of

the barrier islands to open water.

Category 2, “Best Buy” within Budget – The best-buy alternative based on the IWR

screening provides the greatest increase in the value of the output variable for the least

increase in the value of the cost variable. In other words, the best-buy alternative yields

the maximum habitat acres at the lowest cost per unit within the budget. If the budget

falls between two “best buy” alternatives, the lower cost plan could be scaled-up. The

“best buy” alternative is geared less toward the system-wide approach of restoring the

entire barrier island chain and more toward restoring the island or islands that are most

cost-effective.


A-3

• Alternative 2 – Restoration of Timbalier Island to its minimal geomorphologic

form and ecologic function along with 25 years of background erosion/land loss

(i.e. advanced fill).

• Alternative 3 – Restoration of Whiskey Island to its minimal geomorphologic

form and ecologic function along with 5 years of advanced fill combined with

restoration of Timbalier Island to its minimal geomorphologic form and ecologic

function along with 25 years of advanced fill.

• Alternative 4 – Restoration of Whiskey and Trinity Islands to their minimal

geomorphologic form and ecologic function along with 5 years of advanced fill

combined with restoration of Timbalier Island to its minimal geomorphologic

form and ecologic function along with 25 years of advanced fill.

• Alternative 5 – Restoration of Whiskey and Trinity Islands to their minimal

geomorphologic form and ecologic function along with 5 years of advanced fill

combined with restoration of Raccoon and Timbalier Islands to their minimal

geomorphologic form and ecologic function along with 25 years of advanced fill

and construction of a terminal groin on the western end of Raccoon Island.

Category 3, Maximum Number of Islands Constructible with Cleared Sediment

Sources – These alternatives would favor those islands where the total costs are lowest,

allowing for more islands to be created using cleared sediment sources noting they may

or may not be cost effective based on the IWR screening.

• Alternative 6 – Restoration of Raccoon, Whiskey, and Trinity Islands, all to their

minimal geomorphologic form and ecologic function

• Alternative 7 – Restoration of Raccoon, Whiskey, and Trinity Islands, all to their

minimal geomorphologic form and ecologic function, along with construction of

8 additional breakwaters on the western end of Raccoon Island

• Alternative 8 – Restoration of Raccoon, Whiskey, and Trinity Islands, all to their

minimal geomorphologic form and ecologic function, along with construction of a

terminal groin on the western end of Raccoon Island

• Alternative 9 – Restoration of Raccoon, Whiskey, and Timbalier Islands, all to

their minimal geomorphologic form and ecologic function

Category 4, System-wide Barrier Island Restoration – This alternative would take a

full system-wide approach to restoring the Terrebonne Basin barrier system. Each of the

seven barrier islands would be restored to their minimal geomorphologic form and

ecologic function. Similar to the alternatives that include the most islands within the

budget, this alternative may or may not be cost effective based on the IWR screening.

• Alternative 10 – Restoration of Raccoon, Whiskey, Trinity, East, Wine,

Timbalier, and East Timbalier Islands, all to their minimal geomorphologic form

and ecologic function

Category 5, Subsets of NER Plan


A-4

• Alternative 11 – Restoration of Whiskey Island to its minimal geomorphologic

form and ecologic function along with 5 years of background erosion/land loss

• Alternative 12 – Restoration of Trinity Island to its minimal geomorphologic

form and ecologic function along with 5 years of background erosion/land loss

V1, V2, and V3

Variables V1, V2, and V3 represent the percentage of the subaerial portion of the Study

Area that is dune, supratidal, and intertidal habitat, respectively. Dune habitat is defined

as subaerial habitat > 5 ft NAVD 88 and encompasses foredune, dune, and reardune.

Although dune habitat occurs at elevations below 5ft NAVD 88, lower-elevation dunes

are more ephemeral and more frequently overwashed, which reduces their habitat value.

The variable is calculated as the percent of the total subaerial area that is classified as

dune habitat.

Supratidal habitat occurs from 2.0 ft NAVD 88 to 4.9 ft NAVD 88. This habitat type

primarily encompasses swale and may include low-elevation dune and beach habitat.

The variable is calculated as the percent of the total subaerial area that is classified as

supratidal habitat.

Intertidal habitat occurs from 0.0 ft NAVD 88 to 1.9 ft NAVD 88. This habitat type

encompasses intertidal marsh, mudflats, beach, and any other habitat within that elevation

range on the gulfside and bayside of the barrier island. The variable is calculated as the

percent of the total subaerial area that is classified as supratidal habitat.

In order to determine the habitat composition for Future Without Project (FWOP)

conditions, the Project Delivery Team (PDT) developed profiles of each of the seven

islands in the Study Area. The island profiles were delineated in AutoCad using 2006

survey data that was collected as part of the Barrier Island Comprehensive Monitoring

(BICM) program. Since the period of analysis begins in 2012 (designated as TY0), the

profiles were adjusted using average historic erosion rates to account for the six years of

erosion. The adjusted 2012 profiles were then used to create plan-view polygons of each

habitat type to determine acreages of dune, supratidal, and intertidal habitats. This

process was repeated to determine the habitat composition for each target year in the 50-

year period of analysis.

For the Future With Project (FWP) conditions, the PDT developed four restoration

templates (Plans B through E) designed to meet the objectives of the Study. The template

for Plan B restores the minimal geomorphologic form and ecologic function of each

island by restoring the beach, dune, and marsh to their critical dimensions. These

dimensions were defined through analysis of historical planforms and elevations.

Furthermore, these dimensions must be maintained after being subjected to selected

design storms. The design storms that were used in template development included a

hypothetical 50-year storm as well as the varying intensities, durations, and approach

paths of Hurricanes Katrina and Rita, which occurred in 2005, and Hurricanes Gustav

and Ike, which occurred in 2008.


A-5

Plans C through E are scalars of Plan B that incorporate incremental increases in the

scales of beach, dune and marsh planforms and elevations to provide plan formulators the

ability to determine the optimal increment for restoration of the geomorphologic form

and ecologic function of these islands. Plan C provides for the minimal geomorphologic

form and ecologic function on each island along with 5 years of additional protection

from background erosion/land loss (i.e. advanced fill). Plan D provides for the minimal

geomorphologic form and ecologic function on each island along with 10 years of

advanced fill. Plan E provides for the minimal geomorphologic form and ecologic

function on each island along with 25 years of advanced fill.

Profiles were developed in AutoCad for the proposed restoration plans on each island. It

was assumed that construction of the restoration plans would begin in TY0 (i.e. 2012)

and would be completed by TY1 (i.e. 2013). Starting in TY1, each restoration plan was

eroded using the same procedures used for the FWOP conditions.

In order to increase the sustainability of the restoration plans, a renourishment scenario

was also analyzed for each island. The PDT optimized the renourishment quantity and

sequencing by determining the minimum amount needed to maintain the geomorphic

form and ecologic function of the islands throughout the 50-year period of analysis. This

approach minimized the amount of sediment needed for renourishment, thus reducing

costs. The resulting configurations are provided in Table 1. It was assumed that the

renourishment events would take approximately one year to complete. Therefore the

benefits would not be recognized until the year following renourishment. Marsh

renourishment was not included since the initial restoration plan provides for significant

intertidal habitat throughout the 50 year period of analysis.

Table 1. Renourishment sequencing and quantities

Island Plan Renourishment Year Renourishment Plan

Raccoon Plan E w/ TG TY30 Restore Plan B

TY20 Add Plan C Whiskey Plan Ca

TY40 Add Plan B

Trinity Plan C TY25 Add Plan C

Timbalier Plan E TY30 Restore Plan B

a

Whiskey would require two renourishments, one at TY20 and one at TY40

Additional analyses were conducted on Raccoon Island to determine the effectiveness of

breakwaters and terminal groins in reducing shoreline erosion. Raccoon Island was the

only island in the Study Area where these hard structures proved to be cost effective.

Hard structures were accounted for by reducing the rate of shoreline erosion.

The following sections provide variables V1, V2, and V3 for each restoration plan at each

target year.


A-6

Raccoon – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0.0 51 188 239 0% 21% 79%

TY1 0.0 51 184 235 0% 22% 78%

TY5 0.0 30 161 191 0% 16% 84%

TY21 0.0 3 74 77 0% 4% 96%

TY30 0.0 0 55 55 0% 0% 100%

TY40 0.0 0 0 0 0% 0% 0%

TY48 0.0 0 0 0 0% 0% 0%

TY50 0.0 0 0 0 0% 0% 0%

Raccoon – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 51 188 239 0% 21% 79%

TY1 45 227 235 506 9% 45% 46%

TY5 33 194 253 481 7% 40% 53%

TY21 0 143 255 398 0% 36% 64%

TY30 0 83 260 343 0% 24% 76%

TY40 0 25 248 273 0% 9% 91%

TY48 0 0 68 68 0% 0% 100%

TY50 0 0 23 23 0% 0% 100%

Raccoon – FWP (Plan B) with breakwaters:

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 51 188 239 0% 21% 79%

TY1 45 227 237 508 9% 45% 47%

TY5 33 198 254 486 7% 41% 52%

TY21 0 166 255 421 0% 39% 61%

TY30 0 112 264 376 0% 30% 70%

TY40 0 62 259 320 0% 19% 81%

TY48 0 0 82 82 0% 0% 100%

TY50 0 0 38 38 0% 0% 100%

Raccoon – FWP (Plan B) with terminal groin:

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 51 188 239 0% 21% 79%

TY1 45 227 237 508 9% 45% 47%

TY5 33 198 254 485 7% 41% 52%

TY21 0 164 255 419 0% 39% 61%

TY30 0 107 264 371 0% 29% 71%

TY40 0 36 279 315 0% 11% 89%

TY48 0 0 83 83 0% 0% 100%

TY50 0 0 34 34 0% 0% 100%


A-7

Raccoon – FWP (Plan E) with terminal groin:

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 51 188 239 0% 21% 79%

TY1 63 688 38 789 8% 87% 5%

TY5 50 678 39 767 7% 88% 5%

TY30 0 182 466 648 0% 28% 72%

TY40 0 106 486 592 0% 18% 82%

TY50 0 66 468 534 0% 12% 88%

Raccoon – FWP (Plan E) with terminal groin (renourishment at TY30):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 51 188 239 0% 21% 79%

TY1 63 688 38 789 8% 87% 5%

TY5 50 678 39 767 7% 88% 5%

TY10 29 659 40 728 4% 91% 5%

TY20 20 650 39 709 3% 92% 6%

TY30 0 182 466 648 0% 28% 72%

TY31 45 204 468 717 6% 28% 65%

TY40 15 165 486 666 2% 25% 73%

TY50 3 170 468 641 0% 27% 73%

Whiskey – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0.0 377 443 820 0% 46% 54%

TY1 0.0 367 436 803 0% 46% 54%

TY5 0.0 40 692 731 0% 5% 95%

TY10 0.0 4 616 620 0% 1% 99%

TY17 0.0 0 512 512 0% 0% 100%

TY20 0.0 0 468 468 0% 0% 100%

TY30 0.0 0 375 375 0% 0% 100%

TY50 0.0 0 0 0 0% 0% 0%

Whiskey – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 377 443 820 0% 46% 54%

TY1 57 614 509 1180 5% 52% 43%

TY5 53 220 830 1102 5% 20% 75%

TY10 0 164 801 965 0% 17% 83%

TY17 0 49 791 840 0% 6% 94%

TY20 0 0 786 786 0% 0% 100%

TY30 0 0 594 594 0% 0% 100%

TY50 0 0 276 276 0% 0% 100%


A-8

Whiskey – FWP (Plan C):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 377 443 820 0% 46% 54%

TY1 65 830 377 1271 5% 65% 30%

TY5 61 328 808 1197 5% 27% 68%

TY10 57 223 828 1107 5% 20% 75%

TY17 17 126 841 984 2% 13% 85%

TY20 0 84 847 931 0% 9% 91%

TY30 0 0 717 717 0% 0% 100%

TY50 0 0 363 363 0% 0% 100%

Whiskey – FWP (Plan C) with renourishment at TY20 and TY40:

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 0 377 443 820 0% 46% 54%

TY1 65 830 377 1272 5% 65% 30%

TY5 61 328 808 1197 5% 27% 68%

TY10 57 223 828 1108 5% 20% 75%

TY20 0 84 847 931 0% 9% 91%

TY21 65 496 834 1395 5% 36% 60%

TY30 57 223 717 997 6% 22% 72%

TY40 0 84 472 556 0% 15% 85%

TY41 57 387 461 905 6% 43% 51%

TY50 0 164 363 527 0% 31% 69%

Trinity – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 39 232 311 582 7% 40% 53%

TY1 32 206 326 564 6% 37% 58%

TY5 4 137 327 469 1% 29% 70%

TY20 0 3 72 75 0% 4% 96%

TY24 0 2 51 53 0% 4% 96%

TY33 0 0 14 14 0% 0% 100%

TY40 0 0 0 0 0% 0% 0%

TY50 0 0 0 0 0% 0% 0%

Trinity – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 39 232 311 582 7% 40% 53%

TY1 126 338 569 1033 12% 33% 55%

TY5 92 237 626 956 10% 25% 66%

TY20 0 43 627 670 0% 6% 94%

TY24 0 0 560 560 0% 0% 100%

TY33 0 0 406 406 0% 0% 100%

TY40 0 0 279 279 0% 0% 100%

TY50 0 0 33 33 0% 0% 100%


A-9

Trinity – FWP (Plan C):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 39 232 311 582 7% 40% 53%

TY1 129 456 564 1149 11% 40% 49%

TY5 122 316 632 1070 11% 30% 59%

TY20 0 190 594 784 0% 24% 76%

TY31 0 0 543 543 0% 0% 100%

TY40 0 0 380 380 0% 0% 100%

TY50 0 0 199 199 0% 0% 100%

Trinity – FWP (Plan C) with renourishment at TY25:

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 39 232 311 582 7% 40% 53%

TY1 129 456 564 1149 11% 40% 49%

TY5 122 316 632 1070 11% 30% 59%

TY10 67 270 635 972 7% 28% 65%

TY20 0 190 594 784 0% 24% 76%

TY25 0 90 597 687 0% 13% 87%

TY26 129 496 590 1215 11% 41% 49%

TY30 122 320 561 1003 12% 32% 56%

TY40 34 230 380 644 5% 36% 59%

TY50 0 90 199 289 0% 31% 69%

East – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 35 178 71 284 12% 63% 25%

TY1 23 176 59 258 9% 68% 23%

TY5 5 86 110 201 2% 43% 55%

TY20 0 6 58 64 0% 10% 90%

TY22 0 5 49 54 0% 9% 91%

TY29 0 0 20 20 0% 0% 100%

TY40 0 0 0 0 0% 0% 0%

TY50 0 0 0 0 0% 0% 0%

East – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 35 178 71 284 12% 63% 25%

TY1 88 229 362 680 13% 34% 53%

TY5 59 165 404 628 9% 26% 64%

TY20 0 33 401 434 0% 8% 92%

TY22 0 0 378 378 0% 0% 100%

TY29 0 0 301 301 0% 0% 100%

TY40 0 0 171 171 0% 0% 100%

TY50 0 0 46 46 0% 0% 100%


A-10

Wine – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 1 5 6 12 4% 46% 50%

TY1 0 4 7 11 0% 36% 64%

TY5 0 3 6 9 0% 33% 67%

TY20 0 1 3 4 0% 25% 75%

TY29 0 0 1 1 0% 0% 100%

TY35 0 0 0 0 0% 0% 0%

TY40 0 0 0 0 0% 0% 0%

TY50 0 0 0 0 0% 0% 0%

Wine – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 1 5 6 12 4% 46% 50%

TY1 12 97 97 206 6% 47% 47%

TY5 11 75 109 195 6% 38% 56%

TY20 0 47 106 153 0% 31% 69%

TY29 0 16 111 127 0% 12% 88%

TY35 0 12 98 110 0% 11% 89%

TY40 0 0 96 96 0% 0% 100%

TY50 0 0 5 5 0% 0% 100%

Timbalier – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 57 549 374 979 6% 56% 38%

TY1 53 529 373 955 6% 55% 39%

TY5 31 266 541 837 4% 32% 65%

TY20 0 93 289 382 0% 24% 76%

TY41 0 1 33 34 0% 3% 97%

TY50 0 0 2 2 0% 0% 100%

Timbalier – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 57 549 374 979 6% 56% 38%

TY1 155 748 726 1629 10% 46% 45%

TY5 130 566 811 1507 9% 38% 54%

TY20 0 236 829 1065 0% 22% 78%

TY41 0 0 423 423 0% 0% 100%

TY50 0 0 175 175 0% 0% 100%


A-11

Timbalier – FWP (Plan E):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 57 549 374 979 6% 56% 38%

TY1 215 2346 69 2630 8% 89% 3%

TY5 183 2257 71 2511 7% 90% 3%

TY20 0 1996 76 2072 0% 96% 4%

TY41 0 303 1120 1422 0% 21% 79%

TY50 0 53 1088 1141 0% 5% 95%

Timbalier – FWP (Plan E) with renourishment at TY30:

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 57 549 374 980 6% 56% 38%

TY1 215 2346 69 2630 8% 89% 3%

TY5 183 2257 71 2511 7% 90% 3%

TY10 160 2130 74 2364 7% 90% 3%

TY20 0 1996 76 2072 0% 96% 4%

TY30 0 629 1148 1777 0% 35% 65%

TY31 155 667 1146 1968 8% 34% 58%

TY40 13 524 1123 1660 1% 32% 68%

TY50 0 236 1088 1324 0% 18% 82%

East Timbalier – FWOP

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 1 112 119 233 1% 48% 51%

TY1 1 74 133 208 1% 35% 64%

TY5 1 60 140 201 1% 30% 70%

TY10 0 46 111 156 0% 29% 71%

TY20 0 9 98 107 0% 8% 92%

TY43 0 0 13 13 0% 0% 100%

TY45 0 0 10 10 0% 0% 100%

TY50 0 0 4 4 0% 0% 100%

East Timbalier – FWP (Plan B):

Target

Year

Dune

(acres)

Supratidal

(acres)

Intertidal

(acres)

Subaerial

(acres)

V1

(% Dune)

V2

(% Supratidal)

V3

(% Intertidal)

TY0 1 112 119 233 1% 48% 51%

TY1 63 314 452 828 8% 38% 55%

TY5 58 240 476 775 8% 31% 61%

TY10 54 199 474 727 7% 27% 65%

TY20 0 175 456 631 0% 28% 72%

TY43 0 9 286 295 0% 3% 97%

TY45 0 0 206 206 0% 0% 100%

TY50 0 0 7 7 0% 0% 100%


A-12

V4- Vegetative Cover

For each of the subject barrier islands, the subaerial land acreage, total vegetative

coverage, and woody vegetative coverage was determined based on an evaluation of the

most recent high-resolution aerial photography available to our agency (2008 digital

orthophoto quarterquadrangles [DOQQs]). Landscape and vegetative community

polygons were delineated from observable imagery signatures and evaluated at scales

ranging from 1:1,000 to 1:4,000. Our interpretation of landscape and vegetation imagery

signatures was based upon, and verified by, field data collected by an interagency team of

biologists during a July 27 – 29, 2009, site inspection. The results of those calculations

were compared to historical data collected for the respective islands (i.e., data collected

for CWPPRA projects) to ensure a reasonable level of consistency with previous studies

and to corroborate our findings.

Under “future with project” conditions we assumed plantings of dune, supratidal, and

intertidal habitats. We recommend dune plantings include sea oats, bitter panicum, beach

morning glory (if available), and Roseau (use source material for better survivability in

saline conditions).

Raccoon – FWOP

TY0 17% Year 2012

TY1 17%

TY5 12% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY21 7% Continued deterioration and lowering of profile.

TY30 5% Continued deterioration and lowering of profile.

TY40 0% There are no subaerial acres left by target year 40.

TY48 0% The island is no longer subaerial.

TY50 0% The island is no longer subaerial.

Raccoon – FWP (Plan B): Assumptions based on Shell Island project

TY0 17% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (45 dune acres + 227 supratidal acres @ 10% cover) + (212 acres of

marsh platform [90% of 235 intertidal acres = 212 acres of marsh

platform] @ 25% cover)/506 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (33 dune acres + 194 supratidal acres

@ 60% cover) + (228 acres of marsh platform [90% of 253 intertidal acres

= 228 acres of marsh platform] @ 75% cover)/481 subaerial acres

TY21 51% Assume 45% cover of dune and supratidal habitat and 60% vegetative

cover of marsh platform (0 dune acres + 143 supratidal acres @ 45%


A-13

cover) + (230 acres of marsh platform [90% of 255 intertidal acres = 230

acres of marsh platform] @ 60% cover)/398 subaerial acres

TY30 37% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 83 supratidal acres @ 25% cover)

+ (234 acres of marsh platform [90% of 260 intertidal acres = 234 acres of

marsh platform] @ 45% cover)/343 subaerial acres

TY40 22% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 25 supratidal acres @ 15% cover)

+ (223 acres of marsh platform [90% of 248 intertidal acres = 223 acres of

marsh platform] @ 25% cover)/273 subaerial acres

TY48 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(61 acres of marsh platform [90% of 68 intertidal acres = 61 acres of

marsh platform] @ 15% cover)/68 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(21 acres of marsh platform [90% of 23 intertidal acres = 21 acres of

marsh platform] @ 15% cover)/23 subaerial acres

Raccoon – FWP (Plan B) with breakwaters: Assumptions based on Shell Island project

TY0 17% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (45 dune acres + 227 supratidal acres @ 10% cover) + (213 acres of

marsh platform [90% of 237 intertidal acres = 213 acres of marsh

platform] @ 25% cover)/508 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (33 dune acres + 198 supratidal acres

@ 60% cover) + (229 acres of marsh platform [90% of 254 intertidal acres

= 228 acres of marsh platform] @ 75% cover)/486 subaerial acres

TY21 50% Assume 45% cover of dune and supratidal habitat and 60% vegetative

cover of marsh platform (0 dune acres + 167 supratidal acres @ 45%

cover) + (230 acres of marsh platform [90% of 255 intertidal acres = 230

acres of marsh platform] @ 60% cover)/421 subaerial acres

TY30 36% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 112 supratidal acres @ 25%

cover) + (238 acres of marsh platform [90% of 264 intertidal acres = 238

acres of marsh platform] @ 45% cover)/376 subaerial acres

TY40 21% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 62 supratidal acres @ 15% cover)

+ (233 acres of marsh platform [90% of 259 intertidal acres = 233 acres of

marsh platform] @ 25% cover)/320 subaerial acres


A-14

TY48 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(74 acres of marsh platform [90% of 82 intertidal acres = 74 acres of

marsh platform] @ 15% cover)/82 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(34 acres of marsh platform [90% of 38 intertidal acres = 34 acres of

marsh platform] @ 15% cover)/38 subaerial acres

Raccoon – FWP (Plan B) with terminal groin: Assumptions based on Shell Island project

TY0 17% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (45 dune acres + 227 supratidal acres @ 10% cover) + (213 acres of

marsh platform [90% of 237 intertidal acres = 213 acres of marsh

platform] @ 25% cover)/508 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (33 dune acres + 198 supratidal acres

@ 60% cover) + (229 acres of marsh platform [90% of 254 intertidal acres

= 228 acres of marsh platform] @ 75% cover)/485 subaerial acres

TY21 50% Assume 45% cover of dune and supratidal habitat and 60% vegetative

cover of marsh platform (0 dune acres + 164 supratidal acres @ 45%

cover) + (230 acres of marsh platform [90% of 255 intertidal acres = 230

acres of marsh platform] @ 60% cover)/419 subaerial acres

TY30 36% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 107 supratidal acres @ 25%

cover) + (238 acres of marsh platform [90% of 264 intertidal acres = 238

acres of marsh platform] @ 45% cover)/371 subaerial acres

TY40 22% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 36 supratidal acres @ 15% cover)

+ (251 acres of marsh platform [90% of 279 intertidal acres = 251 acres of

marsh platform] @ 25% cover)/315 subaerial acres

TY48 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(75 acres of marsh platform [90% of 83 intertidal acres = 75 acres of

marsh platform] @ 15% cover)/83 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(31 acres of marsh platform [90% of 34 intertidal acres = 31 acres of

marsh platform] @ 15% cover)/34 subaerial acres


A-15

Raccoon – FWP (Plan E) with terminal groin: Assumptions based on Shell Island project

TY0 17% Year 2012

TY1 11% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (63 dune acres + 688 supratidal acres @ 10% cover) + (34 acres of

marsh platform [90% of 38 intertidal acres = 34 acres of marsh platform]

@ 25% cover)/789 subaerial acres

TY5 60% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (50 dune acres + 678 supratidal acres

@ 60% cover) + (35 acres of marsh platform [90% of 39 intertidal acres =

35 acres of marsh platform] @ 75% cover)/767 subaerial acres

TY30 36% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 182 supratidal acres @ 25%

cover) + (419 acres of marsh platform [90% of 466 intertidal acres = 419

acres of marsh platform] @ 45% cover)/646 subaerial acres

TY40 21% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 106 supratidal acres @ 15%

cover) + (437 acres of marsh platform [90% of 486 intertidal acres = 437

acres of marsh platform] @ 25% cover)/592 subaerial acres

TY50 12% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 66 supratidal acres @ 5% cover)

+ (421 acres of marsh platform [90% of 468 intertidal acres = 421 acres of

marsh platform] @ 15% cover)/534 subaerial acres

Raccoon – FWP (Plan E) with terminal groin (renourishment at TY30): Assumptions

based on Shell Island project

TY0 17% Year 2012

TY1 11% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (63 dune acres + 688 supratidal acres @ 10% cover) + (34 acres of

marsh platform [90% of 38 intertidal acres = 34 acres of marsh platform]

@ 25% cover)/789 subaerial acres

TY5 60% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (50 dune acres + 678 supratidal acres

@ 60% cover) + (35 acres of marsh platform [90% of 39 intertidal acres =

35 acres of marsh platform] @ 75% cover)/767 subaerial acres

TY10 51% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (29 dune acres + 659 supratidal acres

@ 50% cover) + (36 acres of marsh platform [90% of 40 intertidal acres =

36 acres of marsh platform] @ 70% cover)/728 subaerial acres


A-16

TY20 50% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (20 dune acres + 650 supratidal acres

@ 50% cover) + (35 acres of marsh platform [90% of 39 intertidal acres =

35 acres of marsh platform] @ 70% cover)/709 subaerial acres

TY30 36% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 182 supratidal acres @ 25%

cover) + (419 acres of marsh platform [90% of 466 intertidal acres = 419

acres of marsh platform] @ 45% cover)/648 subaerial acres

TY31 38% All of the supratidal acreage is unvegetated (covered with spoil) so

supratidal acres are removed from the vegetative cover formula. Assume

45% vegetative cover of dune and 60% vegetative cover of marsh

platform. (45 dune acres @ 45% cover) + (421 acres of marsh platform

[90% of 468 intertidal acres = 421 acres of marsh platform] @ 60%

cover)/717 subaerial acres

TY40 59% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (15 dune acres + 165 supratidal acres

@ 50% cover) + (437 acres of marsh platform [90% of 486 intertidal acres

= 437 acres of marsh platform] @ 70% cover)/666 subaerial acres

TY50 53% Assume 50% cover of dune and supratidal habitat and 60% vegetative

cover of marsh platform (3 dune acres + 170 supratidal acres @ 50%

cover) + (421 acres of marsh platform [90% of 468 intertidal acres = 421

acres of marsh platform] @ 60% cover)/641 subaerial acres

Whiskey – FWOP

TY0 53% Year 2012

TY1 52%

TY5 45% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY10 35% Continued deterioration and lowering of profile.

TY17 25% Continued deterioration and lowering of profile.

TY20 20% Continued deterioration and lowering of profile.

TY30 15% Continued deterioration and lowering of profile.

TY50 0% The island is no longer subaerial.

Whiskey – FWP (Plan B): Assumptions based on Shell Island project

TY0 53% Year 2012

TY1 15% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (57 dune acres + 614 supratidal acres @ 10% cover) + (458 acres of

marsh platform [90% of 509 intertidal acres = 458 acres of marsh

platform] @ 25% cover)/1180 subaerial acres

TY5 66% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (53 dune acres + 220 supratidal acres


A-17

@ 60% cover) + (747 acres of marsh platform [90% of 830 intertidal acres

= 747 acres of marsh platform] @ 75% cover)/1102 subaerial acres

TY10 61% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (0 dune acres + 164 supratidal acres

@ 50% cover) + (721 acres of marsh platform [90% of 801 intertidal acres

= 721 acres of marsh platform] @ 70% cover)/965 subaerial acres

TY17 58% Assume 50% vegetative cover of dune and supratidal habitat and 65%

vegetative cover of marsh platform. (0 dune acres + 49 supratidal acres @

50% cover) + (712 acres of marsh platform [90% of 791 intertidal acres =

712 acres of marsh platform] @ 65% cover)/840 subaerial acres

TY20 54% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 0 supratidal acres @

50% cover) + (707 acres of marsh platform [90% of 786 intertidal acres =

707 acres of marsh platform] @ 70% cover)/786 subaerial acres

TY30 41% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 25% cover)

+ (535 acres of marsh platform [90% of 594 intertidal acres = 535 acres of

marsh platform] @ 45% cover)/594 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(248 acres of marsh platform [90% of 276 intertidal acres = 248 acres of

marsh platform] @ 15% cover)/276 subaerial acres

Whiskey – FWP (Plan C): Assumptions based on Shell Island project

TY0 53% Year 2012

TY1 14% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (65 dune acres + 830 supratidal acres @ 10% cover) + (339 acres of

marsh platform [90% of 377 intertidal acres = 339 acres of marsh

platform] @ 25% cover)/1271 subaerial acres

TY5 65% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (61 dune acres + 328 supratidal acres

@ 60% cover) + (727 acres of marsh platform [90% of 808 intertidal acres

= 727 acres of marsh platform] @ 75% cover)/1197 subaerial acres

TY10 60% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (57 dune acres + 223 supratidal acres

@ 50% cover) + (745 acres of marsh platform [90% of 828 intertidal acres

= 745 acres of marsh platform] @ 70% cover)/1107 subaerial acres

TY17 57% Assume 50% vegetative cover of dune and supratidal habitat and 65%

vegetative cover of marsh platform. (17 dune acres + 126 supratidal acres

@ 50% cover) + (757 acres of marsh platform [90% of 841 intertidal acres

= 757 acres of marsh platform] @ 65% cover)/984 subaerial acres


A-18

TY20 54% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 84 supratidal acres @

50% cover) + (762 acres of marsh platform [90% of 847 intertidal acres =

762 acres of marsh platform] @ 70% cover)/931 subaerial acres

TY30 41% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 25% cover)

+ (645 acres of marsh platform [90% of 717 intertidal acres = 645 acres of

marsh platform] @ 45% cover)/717 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(327 acres of marsh platform [90% of 363 intertidal acres = 327 acres of

marsh platform] @ 15% cover)/363 subaerial acres

Whiskey – FWP (Plan C) with renourishment at TY20 and TY40: Assumptions based on

Shell Island project

TY0 53% Year 2012

TY1 14% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (65 dune acres + 830 supratidal acres @ 10% cover) + (339 acres of

marsh platform [90% of 377 intertidal acres = 339 acres of marsh

platform] @ 25% cover)/1271 subaerial acres

TY5 65% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (61 dune acres + 328 supratidal acres

@ 60% cover) + (727 acres of marsh platform [90% of 808 intertidal acres

= 727 acres of marsh platform] @ 75% cover)/1197 subaerial acres

TY10 60% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (57 dune acres + 223 supratidal acres

@ 50% cover) + (745 acres of marsh platform [90% of 828 intertidal acres

= 745 acres of marsh platform] @ 70% cover)/1107 subaerial acres

TY20 54% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 84 supratidal acres @

50% cover) + (762 acres of marsh platform [90% of 847 intertidal acres =

762 acres of marsh platform] @ 70% cover)/931 subaerial acres

TY21 34% All of the supratidal acreage is unvegetated (covered with spoil) so

supratidal acres are removed from the vegetative cover formula. Assume

45% vegetative cover of dune and 60% vegetative cover of marsh

platform. (65 dune acres @ 45% cover) + (751 acres of marsh platform

[90% of 834 intertidal acres = 751 acres of marsh platform] @ 60%

cover)/1395 subaerial acres

TY30 59% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (57 dune acres + 223 supratidal acres

@ 50% cover) + (745 acres of marsh platform [90% of 717 intertidal acres

= 745 acres of marsh platform] @ 70% cover)/1107 subaerial acres


A-19

TY31 38% All of the supratidal acreage is unvegetated (covered with spoil) so

supratidal acres are removed from the vegetative cover formula. Assume

45% vegetative cover of dune and 60% vegetative cover of marsh

platform. (65 dune acres @ 45% cover) + (645 acres of marsh platform

[90% of 717 intertidal acres = 645 acres of marsh platform] @ 60%

cover)/997 subaerial acres

TY40 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 84 supratidal acres @

50% cover) + (425 acres of marsh platform [90% of 472 intertidal acres =

425 acres of marsh platform] @ 70% cover)/556 subaerial acres

TY41 30% All of the supratidal acreage is unvegetated (covered with spoil) so

supratidal acres are removed from the vegetative cover formula. Assume

45% vegetative cover of dune and 60% vegetative cover of marsh

platform. (57 dune acres @ 45% cover) + (415 acres of marsh platform

[90% of 461 intertidal acres = 415 acres of marsh platform] @ 60%

cover)/905 subaerial acres

TY50 59% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (0 dune acres + 164 supratidal acres

@ 50% cover) + (327 acres of marsh platform [90% of 363 intertidal acres

= 327 acres of marsh platform] @ 70% cover)/527 subaerial acres

Trinity – FWOP

TY0 53% Year 2012

TY1 51%

TY5 45% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY20 15% Continued deterioration and lowering of profile.

TY24 10% Continued deterioration and lowering of profile.

TY33 3% Continued deterioration and lowering of profile.

TY40 0% There are no subaerial acres left by target year 40.

TY50 0% The island is no longer subaerial.

Trinity – FWP (Plan B): Assumptions based on Shell Island project

TY0 53% Year 2012

TY1 17% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (126 dune acres + 338 supratidal acres @ 10% cover) + (512 acres

of marsh platform [90% of 569 intertidal acres = 512 acres of marsh

platform] @ 25% cover)/1033 subaerial acres

TY5 65% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (92 dune acres + 237 supratidal acres

@ 60% cover) + (563 acres of marsh platform [90% of 626 intertidal acres

= 563 acres of marsh platform] @ 75% cover)/956 subaerial acres


A-20

TY20 54% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 43 supratidal acres @

50% cover) + (564 acres of marsh platform [90% of 627 intertidal acres =

564 acres of marsh platform] @ 70% cover)/670 subaerial acres

TY24 50% Assume 35% vegetative cover of dune and supratidal habitat and 55%

vegetative cover of marsh platform. (0 dune acres + 0 supratidal acres @

50% cover) + (504 acres of marsh platform [90% of 560 intertidal acres =

504 acres of marsh platform] @ 70% cover)/560 subaerial acres

TY33 32% Assume 20% vegetative cover of dune and supratidal habitat and 35%

vegetative cover of marsh platform. (0 dune acres + 0 supratidal acres @

20% cover) + (365 acres of marsh platform [90% of 406 intertidal acres =

365 acres of marsh platform] @ 35% cover)/406 subaerial acres

TY40 23% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 15% cover)

+ (251 acres of marsh platform [90% of 279 intertidal acres = 251 acres of

marsh platform] @ 25% cover)/279 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(30 acres of marsh platform [90% of 33 intertidal acres = 30 acres of

marsh platform] @ 15% cover)/33 subaerial acres

Trinity – FWP (Plan C): Assumptions based on Shell Island project

TY0 53% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (129 dune acres + 456 supratidal acres @ 10% cover) + (508 acres

of marsh platform [90% of 564 intertidal acres = 508 acres of marsh

platform] @ 25% cover)/1149 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (122 dune acres + 316 supratidal

acres @ 60% cover) + (569 acres of marsh platform [90% of 632 intertidal

acres = 569 acres of marsh platform] @ 75% cover)/1070 subaerial acres

TY20 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 190 supratidal acres

@ 50% cover) + (535 acres of marsh platform [90% of 594 intertidal acres

= 535 acres of marsh platform] @ 70% cover)/784 subaerial acres

TY31 36% Assume 25% vegetative cover of dune and supratidal habitat and 40%

vegetative cover of marsh platform. (0 dune acres + 0 supratidal acres @

50% cover) + (489 acres of marsh platform [90% of 543 intertidal acres =

489 acres of marsh platform] @ 70% cover)/543 subaerial acres

TY40 23% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 15% cover)


A-21

+ (342 acres of marsh platform [90% of 380 intertidal acres = 342 acres of

marsh platform] @ 25% cover)/380 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(179 acres of marsh platform [90% of 199 intertidal acres = 179 acres of

marsh platform] @ 15% cover)/199 subaerial acres

Trinity – FWP (Plan C) with renourishment at TY25: Assumptions based on Shell Island

project

TY0 53% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (129 dune acres + 456 supratidal acres @ 10% cover) + (508 acres

of marsh platform [90% of 564 intertidal acres = 508 acres of marsh

platform] @ 25% cover)/1149 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (122 dune acres + 316 supratidal

acres @ 60% cover) + (569 acres of marsh platform [90% of 632 intertidal

acres = 569 acres of marsh platform] @ 75% cover)/1070 subaerial acres

TY10 58% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (67 dune acres + 270 supratidal acres

@ 50% cover) + (572 acres of marsh platform [90% of 635 intertidal acres

= 572 acres of marsh platform] @ 70% cover)/972 subaerial acres

TY20 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 190 supratidal acres

@ 50% cover) + (535 acres of marsh platform [90% of 594 intertidal acres

= 535 acres of marsh platform] @ 70% cover)/784 subaerial acres

TY25 51% Assume 30% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 90 supratidal acres @

30% cover) + (537 acres of marsh platform [90% of 597 intertidal acres =

537 acres of marsh platform] @ 60% cover)/687 subaerial acres

TY26 31% All of the supratidal acreage is unvegetated (covered with spoil) so

supratidal acres are removed from the vegetative cover formula. Assume

45% vegetative cover of dune and 60% vegetative cover of marsh

platform. (129 dune acres @ 45% cover) + (531 acres of marsh platform

[90% of 590 intertidal acres = 531 acres of marsh platform] @ 60%

cover)/1215 subaerial acres

TY30 57% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (122 dune acres + 320 supratidal

acres @ 50% cover) + (505 acres of marsh platform [90% of 561 intertidal

acres = 505 acres of marsh platform] @ 70% cover)/1003 subaerial acres

TY40 52% Assume 50% cover of dune and supratidal habitat and 60% vegetative

cover of marsh platform (34 dune acres + 230 supratidal acres @ 50%


A-22

cover) + (342 acres of marsh platform [90% of 380 intertidal acres = 342

acres of marsh platform] @ 60% cover)/644 subaerial acres

TY50 36% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 90 supratidal acres @ 25% cover)

+ (179 acres of marsh platform [90% of 199 intertidal acres = 179 acres of

marsh platform] @ 15% cover)/289 subaerial acres

East – FWOP

TY0 29% Year 2012

TY1 28%

TY5 25% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY20 10% Continued deterioration and lowering of profile.

TY22 8% Continued deterioration and lowering of profile.

TY29 5% Continued deterioration and lowering of profile.

TY40 0% There are no subaerial acres left by target year 40.

TY50 0% The island is no longer subaerial.

East – FWP (Plan B): Assumptions based on Shell Island project

TY0 29% Year 2012

TY1 17% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (88 dune acres + 229 supratidal acres @ 10% cover) + (326 acres of

marsh platform [90% of 362 intertidal acres = 326 acres of marsh

platform] @ 25% cover)/680 subaerial acres

TY5 65% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (59 dune acres + 165 supratidal acres

@ 60% cover) + (364 acres of marsh platform [90% of 404 intertidal acres

= 364 acres of marsh platform] @ 75% cover)/628 subaerial acres

TY20 54% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 33 supratidal acres @

50% cover) + (361 acres of marsh platform [90% of 401 intertidal acres =

361 acres of marsh platform] @ 70% cover)/434 subaerial acres

TY22 54% Assume 40% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 0 supratidal acres @

50% cover) + (340 acres of marsh platform [90% of 378 intertidal acres =

340 acres of marsh platform] @ 70% cover)/378 subaerial acres

TY29 41% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 25% cover)

+ (271 acres of marsh platform [90% of 301 intertidal acres = 271 acres of

marsh platform] @ 45% cover)/301 subaerial acres

TY40 23% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 15% cover)


A-23

+ (154 acres of marsh platform [90% of 171 intertidal acres = 154 acres of

marsh platform] @ 25% cover)/171 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(41 acres of marsh platform [90% of 46 intertidal acres = 41 acres of

marsh platform] @ 15% cover)/46 subaerial acres

Wine – FWOP

TY0 16% Year 2012

TY1 16%

TY5 10% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY20 5% Continued deterioration and lowering of profile.

TY29 2% Continued deterioration and lowering of profile.

TY35 0% There are no subaerial acres left by target year 35.

TY40 0% The island is no longer subaerial.

TY50 0% The island is no longer subaerial.

Wine – FWP (Plan B): Assumptions based on Shell Island project

TY0 16% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (12 dune acres + 97 supratidal acres @ 10% cover) + (87 acres of

marsh platform [90% of 97 intertidal acres = 87 acres of marsh platform]

@ 25% cover)/206 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (11 dune acres + 75 supratidal acres

@ 60% cover) + (98 acres of marsh platform [90% of 109 intertidal acres

= 98 acres of marsh platform] @ 75% cover)/195 subaerial acres

TY20 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 47 supratidal acres @

50% cover) + (95 acres of marsh platform [90% of 106 intertidal acres =

95 acres of marsh platform] @ 70% cover)/153 subaerial acres

TY29 39% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 16 supratidal acres @ 25% cover)

+ (100 acres of marsh platform [90% of 111 intertidal acres = 100 acres of

marsh platform] @ 45% cover)/127 subaerial acres

TY35 26% Assume 20% cover of dune and supratidal habitat and 30% vegetative

cover of marsh platform (0 dune acres + 12 supratidal acres @ 25% cover)

+ (88 acres of marsh platform [90% of 98 intertidal acres = 88 acres of

marsh platform] @ 45% cover)/110 subaerial acres

TY40 23% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 15% cover)


A-24

+ (86 acres of marsh platform [90% of 96 intertidal acres = 86 acres of

marsh platform] @ 25% cover)/96 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(5 acres of marsh platform [90% of 5 intertidal acres = 5 acres of marsh

platform] @ 15% cover)/5 subaerial acres

Timbalier – FWOP

TY0 64% Year 2012

TY1 62%

TY5 55% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY20 25% Continued deterioration and lowering of profile.

TY41 7% Continued deterioration and lowering of profile.

TY50 1% Only 2 subaerial acres remain.

Timbalier – FWP (Plan B): Assumptions based on Shell Island project

TY0 64% Year 2012

TY1 16% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (155 dune acres + 748 supratidal acres @ 10% cover) + (653 acres

of marsh platform [90% of 726 intertidal acres = 653 acres of marsh

platform] @ 25% cover)/1629 subaerial acres

TY5 64% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (130 dune acres + 566 supratidal

acres @ 60% cover) + (730 acres of marsh platform [90% of 811 intertidal

acres = 730 acres of marsh platform] @ 75% cover)/1507 subaerial acres

TY20 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 236 supratidal acres

@ 50% cover) + (746 acres of marsh platform [90% of 829 intertidal acres

= 746 acres of marsh platform] @ 70% cover)/1065 subaerial acres

TY41 23% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 15% cover)

+ (381 acres of marsh platform [90% of 423 intertidal acres = 381 acres of

marsh platform] @ 25% cover)/423 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(158 acres of marsh platform [90% of 175 intertidal acres = 158 acres of

marsh platform] @ 15% cover)/175 subaerial acres

Timbalier – FWP (Plan E): Assumptions based on Shell Island project

TY0 64% Year 2012


A-25

TY1 10% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (215 dune acres + 2346 supratidal acres @ 10% cover) + (62 acres

of marsh platform [90% of 69 intertidal acres = 62 acres of marsh

platform] @ 25% cover)/2630 subaerial acres

TY5 60% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (183 dune acres + 2257 supratidal

acres @ 60% cover) + (64 acres of marsh platform [90% of 71 intertidal

acres = 64 acres of marsh platform] @ 75% cover)/2511 subaerial acres

TY20 50% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 1996 supratidal acres

@ 50% cover) + (68 acres of marsh platform [90% of 76 intertidal acres =

68 acres of marsh platform] @ 70% cover)/2072 subaerial acres

TY41 21% Assume 15% cover of dune and supratidal habitat and 25% vegetative

cover of marsh platform (0 dune acres + 303 supratidal acres @ 15%

cover) + ( acres of marsh platform [90% of 1120 intertidal acres = 1008

acres of marsh platform] @ 25% cover)/1422 subaerial acres

TY50 13% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 53 supratidal acres @ 5% cover)

+ (979 acres of marsh platform [90% of 1088 intertidal acres = 979 acres

of marsh platform] @ 15% cover)/1141 subaerial acres

Timbalier – FWP (Plan E) with renourishment at TY30: Assumptions based on Shell

Island project

TY0 64% Year 2012

TY1 10% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (215 dune acres + 2346 supratidal acres @ 10% cover) + (62 acres

of marsh platform [90% of 69 intertidal acres = 62 acres of marsh

platform] @ 25% cover)/2630 subaerial acres

TY5 60% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (183 dune acres + 2257 supratidal

acres @ 60% cover) + (64 acres of marsh platform [90% of 71 intertidal

acres = 64 acres of marsh platform] @ 75% cover)/2511 subaerial acres

TY10 50% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (160 dune acres + 2130 supratidal

acres @ 50% cover) + (67 acres of marsh platform [90% of 74 intertidal

acres = 67 acres of marsh platform] @ 70% cover)/2364 subaerial acres


A-26

TY20 50% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 1996 supratidal acres

@ 50% cover) + (68 acres of marsh platform [90% of 76 intertidal acres =

68 acres of marsh platform] @ 60% cover)/2072 subaerial acres

TY30 35% Assume 25% cover of dune and supratidal habitat and 45% vegetative

cover of marsh platform (0 dune acres + 629 supratidal acres @ 25%

cover) + (1033 acres of marsh platform [90% of 1148 intertidal acres =

1033 acres of marsh platform] @ 45% cover)/1777 subaerial acres

TY31 35% All of the supratidal acreage is unvegetated (covered with spoil) so

supratidal acres are removed from the vegetative cover formula. Assume

45% vegetative cover of dune and 60% vegetative cover of marsh

platform. (155 dune acres @ 45% cover) + (1031 acres of marsh platform

[90% of 1146 intertidal acres = 1031 acres of marsh platform] @ 60%

cover)/1968 subaerial acres

TY40 59% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (13 dune acres + 524 supratidal acres

@ 50% cover) + (1011 acres of marsh platform [90% of 1123 intertidal

acres = 1011 acres of marsh platform] @ 70% cover)/1660 subaerial acres

TY50 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 236 supratidal acres

@ 50% cover) + (979 acres of marsh platform [90% of 1088 intertidal

acres = 979 acres of marsh platform] @ 60% cover)/1324 subaerial acres

East Timbalier – FWOP

TY0 38% Year 2012

TY1 37%

TY5 35% Project a decrease in percent vegetative cover due to deterioration and

lowering of profile.

TY10 30% Continued deterioration and lowering of profile.

TY20 25% Continued deterioration and lowering of profile.

TY43 10% Continued deterioration and lowering of profile.

TY45 5% Continued deterioration and lowering of profile.

TY50 1% Only 4 subaerial acres remain.

East Timbalier – FWP (Plan B): Assumptions based on Shell Island project

TY0 38% Year 2012

TY1 17% Assume 10% vegetative cover of dune and supratidal habitat and 25%

vegetative cover of marsh platform. Because the amount of intertidal

habitat occurring within the bay-side versus the gulf-side has not been

identified, we assume that 90% of the intertidal habitat is located on the

bay side of islands (i.e., the marsh platform), while 10% occurs on the gulf

side. (63 dune acres + 314 supratidal acres @ 10% cover) + (407 acres of

marsh platform [90% of 452 intertidal acres = 407 acres of marsh

platform] @ 25% cover)/828 subaerial acres

TY5 65% Assume 60% vegetative cover of dune and supratidal habitat and 75%

vegetative cover of marsh platform. (58 dune acres + 240 supratidal acres


A-27

@ 60% cover) + (428 acres of marsh platform [90% of 476 intertidal acres

= 428 acres of marsh platform] @ 75% cover)/775 subaerial acres

TY10 58% Assume 50% vegetative cover of dune and supratidal habitat and 70%

vegetative cover of marsh platform. (54 dune acres + 199 supratidal acres

@ 50% cover) + (427 acres of marsh platform [90% of 474 intertidal acres

= 427 acres of marsh platform] @ 70% cover)/727 subaerial acres

TY20 53% Assume 50% vegetative cover of dune and supratidal habitat and 60%

vegetative cover of marsh platform. (0 dune acres + 175 supratidal acres

@ 50% cover) + (410 acres of marsh platform [90% of 456 intertidal acres

= 410 acres of marsh platform] @ 70% cover)/631 subaerial acres

TY43 18% Assume 10% vegetative cover of dune and supratidal habitat and 20%

vegetative cover of marsh platform. (0 dune acres + 9 supratidal acres @

50% cover) + (257 acres of marsh platform [90% of 286 intertidal acres =

257 acres of marsh platform] @ 70% cover)/ subaerial acres

TY45 18% Assume 10% vegetative cover of dune and supratidal habitat and 20%

vegetative cover of marsh platform. (0 dune acres + 0 supratidal acres @

50% cover) + (185 acres of marsh platform [90% of 206 intertidal acres =

185 acres of marsh platform] @ 70% cover)/206 subaerial acres

TY50 14% Assume 5% cover of dune and supratidal habitat and 15% vegetative

cover of marsh platform (0 dune acres + 0 supratidal acres @ 5% cover) +

(6 acres of marsh platform [90% of 7 intertidal acres = 6 acres of marsh

platform] @ 15% cover)/7 subaerial acres

V5- Woody Cover

For each of the subject barrier islands, the subaerial land acreage, total vegetative

coverage, and woody vegetative coverage was determined based on an evaluation of the

most recent high-resolution aerial photography available to our agency (2008 digital

orthophoto quarterquadrangles [DOQQs]). Landscape and vegetative community

polygons were delineated from observable imagery signatures and evaluated at scales

ranging from 1:1,000 to 1:4,000. Our interpretation of landscape and vegetation imagery

signatures was based upon, and verified by, field data collected by an interagency team of

biologists during a July 27 – 29, 2009, site inspection. The results of those calculations

were compared to historical data collected for the respective islands (i.e., data collected

for CWPPRA projects) to ensure a reasonable level of consistency with previous studies

and to corroborate our findings.

Raccoon – FWOP

TY0 43% Year 2012

TY1 43%

TY5 52% Most of supratidal acreage lost would be unvegetated or vegetated with

non-woody veg. Lost 18 acres vegetation - assume 1/3 woody lost = 12

acres woody remaining/23 acres vegetated = 52%.

TY21 30% Assume some woody losses relative to non-woody as island degrades).

TY30 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.


A-28

TY40 0% No vegetation expected to remain on island.

TY48 0% No vegetation expected to remain on island.

TY50 0% No vegetation expected to remain on island.

Raccoon – FWP (Plan B)

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~58 acres)

are avoided. Percent woody remains constant in that area.

TY5 12% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (308 acres vegetated minus 58 acres mangrove flat = 250 ac. 250 *

5% initial cover = 13 ac. 58 ac mangrove flat * 43% = 25 ac. Total

woody of 38 ac/308 ac total vegetated = 12%).

TY21 23% Mangrove flat (58 ac, 25 ac woody) remains. Woody cover of remaining

vegetated areas increases to 15%. (203-58=145 ac vegetated * 15% = 22

ac. 22+25=47 ac woody. 47 ac/203 vegetated = 23%).

TY30 23% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species..

TY40 23% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species..

TY48 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

TY50 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

Raccoon – FWP (Plan B) with breakwaters

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~58 acres)

are avoided. Percent woody remains constant in that area.

TY5 12% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (308 acres vegetated minus 58 acres mangrove flat = 250 ac. 250 *

5% initial cover = 13 ac. 58 ac mangrove flat * 43% = 25 ac. Total

woody of 38 ac/308 ac total vegetated = 12%).

TY21 23% Mangrove flat (58 ac, 25 ac woody) remains. Woody cover of remaining

vegetated areas increases to 15%. (203-58=145 ac vegetated * 15% = 22

ac. 22+25=47 ac woody. 47 ac/203 vegetated = 23%)

TY30 23% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY40 23% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.


A-29

TY48 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

TY50 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

Raccoon – FWP (Plan B) with terminal groin

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~58 acres)

are avoided. Percent woody remains constant in that area.

TY5 12% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (311 acres vegetated minus 58 acres mangrove flat = 253 ac. 253 *

5% initial cover = 13 ac. 58 ac mangrove flat * 43% = 25 ac. Total

woody of 38 ac/308 ac total vegetated = 12%).

TY21 23% Mangrove flat (58 ac, 25 ac woody) remains. Woody cover of remaining

vegetated areas increases to 15%. (211-58=153 ac vegetated * 15% = 23

ac. 23+25=48 ac woody. 48 ac/211 vegetated = 23%)

TY30 23% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY40 23% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY48 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

TY50 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

Raccoon – FWP (Plan E) with terminal groin

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~58 acres)

are avoided. Percent woody remains constant in that area.

TY5 10% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (460 acres vegetated minus 58 acres mangrove flat = 402 ac. 402 *

5% initial cover = 20 ac. 58 ac mangrove flat * 43% = 25 ac. Total

woody of 45 ac/460 ac total vegetated = 10%).

TY30 22% Mangrove flat (58 ac, 25 ac woody) remains. Woody cover of remaining

vegetated areas increases to 15%. (233-58=175 ac vegetated * 15% = 26

ac. 26+25=51 ac woody. 51 ac/233 vegetated = 22%).

TY40 22% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY50 22% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.


A-30

Raccoon – FWP (Plan E) with terminal groin and renourishment at TY30

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~58 acres)

are avoided. Percent woody remains constant in that area.

TY5 10% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (460 acres vegetated minus 58 acres mangrove flat = 402 ac. 402 *

5% initial cover = 20 ac. 58 ac mangrove flat * 43% = 25 ac. Total

woody of 45 ac/460 ac total vegetated = 10%).

TY10 25% Increase due to growth of planted woody vegetation.

TY20 22% Percentage of woody vegetation decreases as island degrades.

TY30 20% Percentage of woody vegetation decreases as island degrades.

TY31 15% Loss of some woody vegetation due to renourishment, however, mangrove

flats would be avoided.

TY40 20% Increase due to growth of planted woody vegetation.

TY50 20% Woody vegetation percentage remains constant with minimal change in

percent dune and supratidal habitat available.

Whiskey – FWOP

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43%

TY5 46% Most of supratidal acreage lost would be unvegetated or vegetated with

non-woody veg. Lost 106 acres vegetation - assume 1/3 woody lost = 152

acres woody remaining/329 acres vegetated = 46%.

TY10 40% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY17 35% Only intertidal remains. All supratidal acreage lost. Percentage of woody

vegetation decreases as island degrades. Only one woody species

(mangrove) present. Divide SI by 2.

TY20 20% Only intertidal remains. . Percentage of woody vegetation decreases as

island degrades. Only one woody species (mangrove) present. Divide SI

by 2.

TY30 0% No vegetation expected to remain on island.

TY50 0% No vegetation expected to remain on island.

Whiskey – FWP (Plan B)

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~190

acres) are avoided. Percent woody remains constant in that area.


A-31

TY5 20% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (727 acres vegetated minus 286 acres mangrove flat = 441 ac. 441 *

5% initial cover = 22 ac. 286 ac mangrove flat * 43% = 123 ac. Total

woody of 145 ac/727 ac total vegetated = 20%).

TY10 29% Mangrove flat (286 ac, 123 ac woody) remains. Woody cover of

remaining vegetated areas increases to 15%. (589-286=303 ac vegetated *

15% = 45 ac. 45+123=168 ac woody. 168 ac/589 vegetated = 29%)

TY17 29% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY20 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

TY30 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

TY50 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

Whiskey – FWP (Plan C)

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~190

acres) are avoided. Percent woody remains constant in that area.

TY5 19% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (778 acres vegetated minus 286 acres mangrove flat = 492 ac. 492 *

5% initial cover = 25 ac. 286 ac mangrove flat * 43% = 123 ac. Total

woody of 148 ac/778 ac total vegetated = 19%).

TY10 27% Mangrove flat (286 ac, 123 ac woody) remains. Woody cover of

remaining vegetated areas increases to 15%. (664-286=378 ac vegetated *

15% = 57 ac. 57+123=180 ac woody. 180 ac/664 vegetated = 27%)

TY17 27% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY20 20% Almost all supratidal lost. Most of vegetation would be marsh grass.

Only one woody species (mangrove) present. Divide SI by 2.

TY30 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

TY50 20% Only intertidal remains. Most of vegetation would be marsh grass. Only

one woody species (mangrove) present. Divide SI by 2.

Whiskey – FWP (Plan C) with renourishment at TY20 and TY40

TY0 43% Year 2012. 43% of the vegetated subaerial acres are vegetated with

woody species.

TY1 43% Burial of woody vegetation is minimized, since mangrove flats (~190

acres) are avoided. Percent woody remains constant in that area.


A-32

TY5 19% Black mangrove and other available woody vegetation installed on dune

and swale in TY2 or TY3 (15% of installed vegetation is woody).

Existing mangrove flat still there, but smaller proportion of total vegetated

area. (778 acres vegetated minus 286 acres mangrove flat = 492 ac. 492 *

5% initial cover = 25 ac. 286 ac mangrove flat * 43% = 123 ac. Total

woody of 148 ac/778 ac total vegetated = 19%).

TY10 27% Mangrove flat (286 ac, 123 ac woody) remains. Woody cover of

remaining vegetated areas increases to 15%. (664-286=378 ac vegetated *

15% = 57 ac. 57+123=180 ac woody. 180 ac/664 vegetated = 27%)

TY20 20% Decrease in woody vegetation due to losses of dune and supratidal

acreage.

TY21 15% Loss of some woody vegetation due to renourishment, however, mangrove

flats would be avoided.

TY30 25% Increase due to growth of planted woody vegetation.

TY40 20% Percentage of woody vegetation decreases as island degrades.

TY41 15% Loss of some woody vegetation due to renourishment, however, mangrove

flats would be avoided.

TY50 20% Increase due to growth of planted woody vegetation.

Trinity – FWOP

TY0 59% Year 2012. 59% of the vegetated subaerial acres are vegetated with

woody species.

TY1 59%

TY5 68% Most of supratidal acreage lost would be unvegetated or vegetated with

non-woody veg. Lost 77 acres vegetation - assume 1/3 woody lost = 144

acres woody remaining/211 acres vegetated = 68%.

TY20 40% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY24 30% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY33 20% Only intertidal remains. All supratidal acreage lost. Percentage of woody

vegetation decreases as island degrades. Only one woody species

(mangrove) present. Divide SI by 2.

TY40 0% No vegetation expected to remain on island.

TY50 0% No vegetation expected to remain on island.

Trinity – FWP (Plan B)

TY0 59% Year 2012. 59% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species.


A-33

TY24 30% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species. No supratidal acreage

left. Only one species of woody (Mangrove). Divide SI by 2.

TY33 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

TY40 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

TY50 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

Trinity – FWP (Plan C)

TY0 59% Year 2012. 59% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species.

TY31 30% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species. No supratidal acreage

left. Only one species of woody (Mangrove). Divide SI by 2.

TY40 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

TY50 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

Trinity – FWP (Plan C) with renourishment at TY25

TY0 59% Year 2012. 59% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY10 15% Increase due to growth of planted woody vegetation.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species.

TY25 20% Woody vegetation percentage remains constant.

TY26 15% Loss of some woody vegetation due to renourishment.

TY30 20% Increase due to growth of planted woody vegetation.

TY40 20% Woody vegetation percentage remains constant.

TY50 20% Woody vegetation percentage remains constant.

East – FWOP

TY0 56% Year 2012. 56% of the vegetated subaerial acres are vegetated with

woody species.

TY1 56%


A-34

TY5 68% Most of supratidal acreage lost would be unvegetated or vegetated with

non-woody veg. Lost 22 acres vegetation - assume 1/3 woody lost = 33

acres woody remaining/50 acres vegetated = 66%.

TY20 40% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY22 30% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY29 20% Only intertidal remains. All supratidal acreage lost. Percentage of woody

vegetation decreases as island degrades. Only one woody species

(mangrove) present. Divide SI by 2.

TY40 0% No vegetation expected to remain on island.

TY50 0% No vegetation expected to remain on island.

East – FWP (Plan B)

TY0 56% Year 2012. 56% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species.

TY22 30% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species. No supratidal acreage

left. Only one species of woody (Mangrove). Divide SI by 2.

TY29 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

TY40 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

TY50 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

Wine – FWOP

TY0 0% Year 2012. 0% of the vegetated subaerial acres are vegetated with woody

species.

TY1 0% No woody vegetation expected to establish.

TY5 0% No woody vegetation expected to establish.

TY20 0% No woody vegetation expected to establish.

TY29 0% No woody vegetation expected to establish.

TY35 0% No woody vegetation expected to establish.

TY40 0% No woody vegetation expected to establish.

TY50 0% No woody vegetation expected to establish.


A-35

Wine – FWP (Plan B)

TY0 0% Year 2012. 0% of the vegetated subaerial acres are vegetated with woody

species.

TY1 0% No woody vegetation established yet.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY20 15% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species.

TY29 15% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY35 15% Woody percentage remains constant as supratidal acreage is lost.

Mangrove dominates woody species.

TY40 15% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.

TY50 5% Very little intertidal acreage remains. Overwash processes dominate,

reducing mangrove area. Divide SI by 2.

Timbalier – FWOP

TY0 61% Year 2012. 61% of the vegetated subaerial acres are vegetated with

woody species.

TY1 61%

TY5 69% Most of supratidal acreage lost would be unvegetated or vegetated with

non-woody veg. Lost 132 acres vegetation - assume 1/3 woody lost = 317

acres woody remaining/460 acres vegetated = 69%.

TY20 50% Assume some woody losses relative to non-woody as island degrades.

TY41 20% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY50 0% Only very little intertidal remains. All supratidal acreage lost. No woody

species are expected to remain.

Timbalier – FWP (Plan B)

TY0 61% Year 2012. 61% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species.

TY41 30% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Mangrove dominates woody species. No supratidal acreage

left. Only one species of woody (Mangrove). Divide SI by 2.

TY50 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Divide SI by 2.


A-36

Timbalier – FWP (Plan E)

TY0 61% Year 2012. 61% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Large area of supratidal remains. Mangrove dominates

woody species.

TY41 30% Percentage of mangrove cover increases though recruitment and

durability. Supratidal acreage converts to intertidal.

TY50 30% Percentage of mangrove cover remains constant as supratidal and

intertidal acreages decrease.

Timbalier – FWP (Plan E) with renourishment at TY30

TY0 61% Year 2012. 61% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY10 15% Increase due to growth of planted woody vegetation.

TY20 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion. Large area of supratidal remains. Mangrove dominates

woody species.

TY30 20% Woody vegetation percentage remains constant.

TY31 15% Loss of some woody vegetation due to renourishment.

TY40 20% Increase due to growth of planted woody vegetation.

TY50 20% Woody vegetation percentage remains constant.

East Timbalier – FWOP

TY0 61% Year 2012. 61% of the vegetated subaerial acres are vegetated with

woody species.

TY1 61%

TY5 64% Most of supratidal acreage lost would be unvegetated or vegetated with

non-woody veg. Lost 7 acres vegetation - assume 1/3 woody lost = 45

acres woody remaining/70 acres vegetated = 64%.

TY10 50% Assume some woody losses relative to non-woody as island degrades.

TY20 40% Almost all supratidal acreage lost. Treat as though only intertidal remains.

Percentage of woody vegetation decreases as island degrades. Only one

woody species (mangrove) present. Divide SI by 2.

TY43 20% Only intertidal remains. All supratidal acreage lost. Percentage of woody

vegetation decreases as island degrades. Only one woody species

(mangrove) present. Divide SI by 2.

TY45 0% Only very little intertidal remains. All supratidal acreage lost. No woody

species are expected to remain.


A-37

TY50 0% Only very little intertidal remains. All supratidal acreage lost. No woody

species are expected to remain.

East Timbalier – FWP (Plan B)

TY0 61% Year 2012. 61% of the vegetated subaerial acres are vegetated with

woody species.

TY1 5% Burial of majority of woody vegetation is expected.

TY5 10% Black mangrove and other available woody vegetation installed in TY2 or

TY3.

TY10 20% Woody percentage increases as herbaceous vegetation is lost in greater

proportion and mangrove recruits. Mangrove dominates woody species.

TY20 30% Woody percentage increases as herbaceous vegetation is lost in greater

proportion and mangrove recruits. Mangrove dominates woody species.

TY43 30% Percentage of mangrove cover remains constant as supratidal and

intertidal acreages decrease.

TY45 30% Percentage of mangrove cover remains constant as intertidal acreage

decreases. Only one species remains (Mangrove). Divide SI by 2.

TY50 10% Very little intertidal acreage remains. Overwash processes dominate,

reducing mangrove area. Divide SI by 2.

V6- Edge and Interspersion

This variable is intended to capture the relative juxtaposition of intertidal, subaerial

habitat (vegetated and unvegetated) and intra-island aquatic habitats such as ponds,

lagoons, and tidal creeks associated with barrier islands. The variable is made up of five

classes:

• Class 1 (V6 = 1.0): Represents unvegetated flats and healthy back-barrier marsh

with a high degree of tidal creeks, tidal channels, ponds, and/or lagoons.

• Class 2 (V6 = 0.8): Represents a high degree of interspersion, but usually

indicates the beginning of marsh breakup and degradation.

• Class 3 (V6 = 0.6): Represents the development of larger open water areas due to

overwash and subsidence. Class 3 is also applied to projects designed to create

intertidal marsh because they lack functionally distinct interspersion and provide

basically one intertidal habitat type.

• Class 4 (V6 = 0.4): Represents extreme stages of subsidence of the dominance of

breaching with unstable overwash flats.

• Class 5 (V6 = 0.1): Consists of no emergent, intertidal land.

A high degree of dispersion is considered to be optimal (V6 = 1.0) and the lowest

expression of interspersion (open water) is assumed to be less desirable in terms of

community-based function quality (V5 = 0.1).

Interspersion for the TBBSR Study was determined by tracking the evolution of the

intertidal habitat over the 50-year period of analysis. Existing supratidal habitat that

subsides and becomes intertidal habitat was assigned a Class 1 rating. As larger open


A-38

water areas continue to develop in these intertidal zones, the classification ratings are

increased (i.e. become less optimal).

Any new intertidal marsh constructed as part of the project is first assigned a Class 3

rating since the retention dikes prevent the formation of tidal access. As these retention

dikes degrade, tidal channels are formed. These channels provide the optimal amount of

interspersion (Class 1). The following sections discuss the derivation of variable V6 for

each target year.

Raccoon – FWOP

TY0 0.64 10% Class 1; 90% Class 3. This includes 53 acres of CWPPRA project

TE-48 (Class 3), 20 acres of existing mangroves (Class 1), and 116 acres

of other intertidal area (Class 3). It was assumed that CWPPRA project

TE-48 was constructed at TY0 and that it was new confined carpet marsh

with retention dikes that would prevent tidal access. According to aerial

photography, the existing mangrove stands appear to have healthy

interspersion.

TY1 0.64 10% Class 1; 90% Class 3. It was assumed that the retention dikes for TE48 were not yet degraded. The existing mangrove stands were assumed to

maintain a healthy amount of interspersion at TY1 and were thus assigned

a Class 1 rating.

TY5 0.64 47% Class 1; 7% Class 3; 46% Class 4. The retention dikes for TE-48 are

expected to degrade, thus providing tidal access. Therefore, the 53-acre

CWPPRA project was assigned a Class 1 rating.

TY10 0.58 39% Class 2; 14% Class 3; 47% Class 4

TY20 0.54 70% Class 3; 30% Class 4

TY21 0.53 Interpolated

TY30 0.40 100% Class 4

TY40 0.10 100% Class 5 (no subaerial habitat)

TY48 0.10 100% Class 5 (no subaerial habitat)

TY50 0.10 100% Class 5 (no subaerial habitat)

Raccoon – FWP (Plan B):

TY0 0.64 Same as FWOP

TY1 0.70 26% Class 1; 74% Class 3. This includes 53 acres of CWPPRA project

TE-48 (Class 3), 20 acres of existing mangroves (Class 1), 121 acres of

proposed marsh template (Class 3) and 41 acres of other intertidal area

(Class 1 It was assumed that CWPPRA project TE-48 was constructed at

TY0 and that it was new confined carpet marsh with retention dikes that

would temporarily prevent the formation of tidal channels. Retention

dikes will also be constructed as part of the proposed marsh template. The

existing mangrove stands were assumed to maintain a healthy amount of

interspersion at TY1 and were thus assigned a Class 1 rating.

TY5 0.98 94% Class 1; 6% Class 3. This includes 53 acres of TE-48 (now a Class

1), 20 acres of existing mangroves (still a Class 1), 121 acres of proposed

marsh template (now a Class 1) and 60 acres of other intertidal area (16


A-39

acres of Class 3 and 44 acres of Class 1). It was assumed that retention

dikes constructed for CWPPRA project TE-48 and for the proposed marsh

template would degrade, thus providing tidal access.

TY10 0.95 85% Class 1; 8% Class 2; 7% Class 3

TY20 0.78 10% Class 1; 69% Class 2; 21% Class 3

TY21 0.77 Interpolated

TY30 0.70 25% Class 1; 75% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat at this point, thus increasing the percentage of Class 1

habitat.

TY40 0.68 23% Class 1; 69% Class 3; 8% Class 4

TY48 0.46 Interpolated

TY50 0.40 100% Class 4

Raccoon – FWP (Plan B) with breakwaters:

TY0 0.64 Same as FWOP

TY1 0.71 27% Class 1; 73% Class 3. This includes 53 acres of CWPPRA project

TE-48 (Class 3), 20 acres of existing mangroves (Class 1), 121 acres of

proposed marsh template (Class 3) and 43 acres of other intertidal area

(Class 1). It was assumed that CWPPRA project TE-48 was constructed

at TY0 and that it was new confined carpet marsh with retention dikes that

would temporarily prevent the formation of tidal channels. Retention

dikes will also be constructed as part of the proposed marsh template. The

existing mangrove stands were assumed to maintain a healthy amount of

interspersion at TY1 and were thus assigned a Class 1 rating.

TY5 0.97 92% Class 1; 8% Class 3. This includes 53 acres of TE-48 (now a Class

1), 20 acres of existing mangroves (still a Class 1), 121 acres of proposed

marsh template (now a Class 1) and 61 acres of other intertidal area (21

acres of Class 3 and 40 acres of Class 1). It was assumed that retention

dikes constructed for CWPPRA project TE-48 and for the proposed marsh

template would degrade, thus providing tidal access.

TY10 0.96 85% Class 1; 8% Class 2; 7% Class 3

TY20 0.77 90% Class 2; 8% Class 3; 2% Class 4

TY21 0.77 Interpolated

TY30 0.70 25% Class 1; 75% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat at this point, thus increasing the percentage of Class 1

habitat.

TY40 0.66 19% Class 1; 73% Class 3; 8% Class 4

TY48 0.45 Interpolated

TY50 0.40 100% Class 4

Raccoon – FWP (Plan B) with terminal groin:

TY0 0.64 Same as FWOP

TY1 0.71 26% Class 1; 74% Class 3. This includes 53 acres of CWPPRA project

TE-48 (Class 3), 20 acres of existing mangroves (Class 1), 121 acres of

proposed marsh template (Class 3) and 43 acres of other intertidal area

(Class 1). It was assumed that CWPPRA project TE-48 was constructed


A-40

at TY0 and that it was new confined carpet marsh with retention dikes that

would temporarily prevent the formation of tidal channels. Retention

dikes will also be constructed as part of the proposed marsh template. The

existing mangrove stands were assumed to maintain a healthy amount of

interspersion at TY1 and were thus assigned a Class 1 rating.

TY5 0.97 93% Class 1; 7% Class 3. This includes 53 acres of TE-48 (now Class 1),

20 acres of existing mangroves (still Class 1), 121 acres of proposed

marsh template (now Class 1) and 60 acres of other intertidal area (20

acres of Class 3 and 40 acres of Class 1). It was assumed that retention

dikes constructed for CWPPRA project TE-48 and for the proposed marsh

template would degrade, thus providing tidal access.

TY10 0.95 84% Class 1; 8% Class 2; 8% Class 3

TY20 0.75 3% Class 1; 69% Class 2; 27% Class 3; 1% Class 4

TY21 0.74 Interpolated

TY30 0.70 25% Class 1; 75% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat at this point, thus increasing the percentage of Class 1

habitat.

TY40 0.69 25% Class 1; 67% Class 3; 8% Class 4

TY48 0.46 Interpolated

TY50 0.40 100% Class 4

Raccoon – FWP (Plan E) with terminal groin:

TY0 0.64 Same as FWOP

TY1 1.00 100% Class 1. The design elevations of Plan E are significantly larger

than those of Plan B. The proposed marsh template is constructed at an

elevation greater than +2 ft NAVD 88 and therefore is not considered to

be intertidal habitat. The proposed marsh template is not expected to be

converted to intertidal habitat until TY30. At TY1, there is only 38 acres

of intertidal habitat, 20 of which consists of the existing mangrove habitat.

This habitat was assumed to have optimal interspersion (Class 1).

TY5 0.84 59% Class 1; 41% Class 3.

TY10 0.80 100% Class 2. The Class 3 habitat from TY5 is converted to open water.

TY20 0.79 48% Class 1; 52% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat at this point. This habitat is assumed to have optimal

interspersion. The Class 2 habitat from TY10 is converted to Class 3.

TY30 0.68 21% Class 1; 79% Class 3. This includes the 53-acres CWPPRA project

(Class 3), the 318-acre proposed marsh template, and the remaining

intertidal area. The proposed marsh template is converted to intertidal

habitat at TY30 due to subsidence. Since the marsh template has been at a

higher elevation, tidal inlets have not yet formed. Therefore, the marsh

template was assigned a Class 3 rating. CWPPRA project TE-48, which

also is converted to intertidal habitat, was assigned a Class 3 rating. The

remaining intertidal area was assigned a Class 1 rating since it was

assumed to have optimal interspersion.


A-41

TY40 0.97 92% Class 1; 8% Class 3. It was assumed that tidal canals would have

become established in CWPPRA project TE-48 and in the marsh template.

Therefore they were assigned a Class 1 rating.

TY50 0.71 79% Class 2; 12% Class 3; 9% Class 4.

Raccoon – FWP (Plan E) with terminal groin (renourishment at TY30):

TY0 0.64 Same as FWOP

TY1 1.00 100% Class 1. The design elevations of Plan E are significantly larger

than those of Plan B. The proposed marsh template is constructed at an

elevation greater than +2 ft NAVD 88 and therefore is not considered to

be intertidal habitat. The proposed marsh template is not expected to be

converted to intertidal habitat until TY30. At TY1, there is only 38 acres

of intertidal habitat, 20 of which consists of the existing mangrove habitat.

This habitat was assumed to have optimal interspersion (Class 1).

TY5 0.84 59% Class 1; 41% Class 3.

TY10 0.80 100% Class 2. The Class 3 habitat from TY5 is converted to open water.

TY20 0.79 48% Class 1; 52% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat at this point. This habitat is assumed to have optimal

interspersion. The Class 2 habitat from TY10 is converted to Class 3.

TY30 0.68 21% Class 1; 79% Class 3. This includes the 53-acres CWPPRA project

(Class 3), the 318-acre proposed marsh template, and the remaining

intertidal area. The proposed marsh template is converted to intertidal

habitat at TY30 due to subsidence. Since the marsh template has been at a

higher elevation, tidal inlets have not yet formed. Therefore, the marsh

template was assigned a Class 3 rating. CWPPRA project TE-48, which

also is converted to intertidal habitat, was assigned a Class 3 rating. The

remaining intertidal area was assigned a Class 1 rating since it was

assumed to have optimal interspersion.

TY31 0.64 19% Class 1; 1% Class 2; 80% Class 3. This includes the 53-acres

CWPPRA project (Class 3), the 318-acre proposed marsh template, and

the remaining intertidal area. The proposed marsh template is converted

to intertidal habitat at TY30 due to subsidence. Since the marsh template

has been at a higher elevation, tidal inlets have not yet formed. Therefore,

the marsh template was assigned a Class 3 rating. CWPPRA project TE48, which also is converted to intertidal habitat, was assigned a Class 3

rating. The remaining intertidal area was assigned a Class 1 or 2 rating

since it was assumed to have optimal or near-optimal interspersion. The

dune and supratidal portions of the island are renourished at TY31.

However, this will not have an immediate impact on interspersion since it

does not immediately affect intertidal habitat.

TY40 0.96 90% Class 1; 10% Class 3. It was assumed that tidal canals would have

become established in CWPPRA project TE-48 and in the marsh template.

Therefore they were assigned a Class 1 rating.


A-42

TY50 0.75 79% Class 2; 17% Class 3; 4% Class 4. By TY50, a portion of the

renourished dune and supratidal habitat is expected to subside and become

intertidal habitat.

Whiskey – FWOP

TY0 0.86 64% Class 1; 36% Class 3. At TY0, CWPPRA project TE-50 is greater

than +2ft NAVD 88. Since TE-50 is not intertidal, it does not contribute

to the interspersion variable.

TY1 0.80 64% Class 1; 4% Class 3; 32% Class 4. At TY1, CWPPRA project TE-50

is greater than +2ft NAVD 88. Since TE-50 is not intertidal, it does not

contribute to the interspersion variable.

TY5 0.82 46% Class 1 (TE-50 becomes intertidal); 34% Class 2 (existing mangrove

stands begin to break up); 3% Class 3; 17% Class 4.

TY10 0.69 50% Class 2 (TE-50 begins to break up); 45% Class 3; 5% Class 4

TY17 0.56 Interpolated

TY20 0.52 59% Class 3; 41% Class 4

TY30 0.10 100% Class 5 (no subaerial habitat)

TY40 0.10 100% Class 5 (no subaerial habitat)

TY50 0.10 100% Class 5 (no subaerial habitat)

Whiskey – FWP (Plan B):

TY0 0.86 Same as FWOP

TY1 0.92 81% Class 1; 19% Class 3. This includes 284 acres of existing mangroves

(Class 1), the 100-acre proposed marsh template (Class 3), and 125 acres

of other intertidal habitat (Class 1). At TY1, the elevation of CWPPRA

project TE-50 is greater than +2ft NAVD 88. Since TE-50 is not

intertidal, it does not contribute to the interspersion variable. It was

assumed that the proposed marsh template would function as new

confined carpet marsh with retention dikes that would temporarily prevent

the formation tidal canals. Therefore, the marsh template was assigned a

Class 3 rating. The existing mangrove stands were assumed to maintain a

healthy amount of interspersion at TY1 and were thus assigned a Class 1

rating.

TY5 0.96 89% Class 1; 11% Class 3. This includes the 316-acre CWPPRA project

TE-50 (Class 3), 238 acres of existing mangroves (still Class 1), the 100-

acre proposed marsh template (now Class 1), and 175 acres of other

intertidal habitat (93 acres of Class 3 and 82 acres of Class 1). At TY5,

CWPPRA project TE-50 is expected to subside and become intertidal

habitat. Since the CWPPRA project has been at a higher elevation, tidal

inlets have not yet formed. Therefore, the TE-50 was assigned a Class 3

rating. It was assumed that retention dikes constructed for the proposed

marsh template would degrade, thus providing tidal access.

TY10 0.92 64% Class 1; 30% Class 2; 6% Class 3

TY17 0.80 Interpolated

TY20 0.77 17% Class 1; 53% Class 2; 30% Class 3


A-43

TY30 0.60 100% Class 3

TY40 0.54 70% Class 3; 30% Class 4

TY50 0.40 100% Class 4

Whiskey – FWP (Plan C):

TY0 0.86 Same as FWOP

TY1 1.00 100% Class 1. This includes 284 acres of existing mangroves (Class 1),

and 125 acres of other intertidal habitat (Class 1). At TY1, the elevations

of CWPPRA project TE-50 and the proposed marsh template is greater

than +2ft NAVD 88. Since these two components are not intertidal, they

does not contribute to the interspersion variable. The existing mangrove

stands were assumed to maintain a healthy amount of interspersion at TY1

and were thus assigned a Class 1 rating.

TY5 0.91 78% Class 1; 22% Class 3. This includes the 316-acre CWPPRA project

TE-50 (Class 1), 238 acres of existing mangroves (still Class 1), the 110-

acre proposed marsh template (Class 3), and 145 acres of other intertidal

habitat (65 acres of Class 3 and 80 acres of Class 1). At TY5, CWPPRA

project TE-50 is expected to subside and become intertidal habitat. It was

assumed that retention dikes constructed for the CWPPRA project TE-50

and the proposed marsh template would degrade, thus providing tidal

access.

TY10 0.92 64% Class 1; 29% Class 2; 7% Class 3

TY17 0.80 Interpolated

TY20 0.79 22% Class 1; 50% Class 2; 28% Class 3

TY30 0.65 12% Class 1; 88% Class 3

TY40 0.54 69% Class 3; 31% Class 4

TY50 0.40 100% Class 4

Whiskey – FWP (Plan C) with renourishment at TY20 and TY40:

TY0 0.86 Same as FWOP

TY1 1.00 100% Class 1. This includes 284 acres of existing mangroves (Class 1),

and 125 acres of other intertidal habitat (Class 1). At TY1, the elevations

of CWPPRA project TE-50 and the proposed marsh template is greater

than +2ft NAVD 88. Since these two components are not intertidal, they

does not contribute to the interspersion variable. The existing mangrove

stands were assumed to maintain a healthy amount of interspersion at TY1

and were thus assigned a Class 1 rating.

TY5 0.91 78% Class 1; 22% Class 3. This includes the 316-acre CWPPRA project

TE-50 (Class 1), 238 acres of existing mangroves (still Class 1), the 110-

acre proposed marsh template (Class 3), and 145 acres of other intertidal

habitat (65 acres of Class 3 and 80 acres of Class 1). At TY5, CWPPRA

project TE-50 is expected to subside and become intertidal habitat. It was

assumed that retention dikes constructed for the CWPPRA project TE-50

and the proposed marsh template would degrade, thus providing tidal

access.

TY10 0.92 64% Class 1; 29% Class 2; 7% Class 3


A-44

TY20 0.79 22% Class 1; 50% Class 2; 28% Class 3

TY21 0.71 2% Class 1; 51% Class 2; 47% Class 3. The dune and supratidal portions

of the island are renourished at TY21. However, this will not have an

immediate impact on interspersion since it does not immediately affect

intertidal habitat.

TY30 0.66 14% Class 1; 86% Class 3. A large slug of supratidal habitat is expected

to become intertidal habitat at TY30.

TY40 0.55 4% Class 1; 65% Class 3; 31% Class 4

TY41 0.53 67% Class 3; 32% Class 4. The dune and supratidal portions of the island

are renourished again at TY41. However, this will not have an immediate

impact on interspersion since it does not immediately affect intertidal

habitat.

TY50 0.40 100% Class 4

Trinity – FWOP

TY0 0.60 100% Class 3. Aerial photography indicates the development of larger

open water areas within the intertidal zone.

TY1 0.60 100% Class 3

TY5 0.48 40% Class 3; 60% Class 4

TY10 0.47 35% Class 3; 65% Class 4

TY20 0.40 100% Class 4

TY24 0.40 100% Class 4

TY30 0.40 100% Class 4

TY33 0.40 100% Class

TY40 0.10 100% Class 5 (no subaerial habitat)

TY50 0.10 100% Class 5 (no subaerial habitat)

Trinity – FWP (Plan B):

TY0 0.60 Same as FWOP

TY1 0.64 10% Class 1; 90% Class 3. This includes 512 acres of the proposed marsh

template (Class 3) and 57 acres of other intertidal habitat (Class 1). It was

assumed that the proposed marsh template would function as new

confined carpet marsh with retention dikes that would temporarily prevent

the formation tidal canals. Therefore, the marsh template was assigned a

Class 3 rating. There are no existing mangrove stands on Trinity Island.

TY5 1.00 100% Class 1. It was assumed that retention dikes constructed for the

proposed marsh template would degrade, thus providing tidal access.

Therefore the proposed marsh template was assigned a Class 1 rating. The

remaining intertidal habitat was also assigned a Class 1 rating because it

was assumed to have optimal interspersion.

TY10 0.99 97% Class 1; 3% Class 3

TY20 0.84 18% Class 1; 82% Class 2. The Class 3 habitat from TY10 is expected to

be converted to open water.

TY24 0.75 Interpolated

TY30 0.63 8% Class 1; 92% Class 3.

TY33 0.57 Interpolated


A-45

TY40 0.42 11% Class 3; 89% Class 4.

TY50 0.40 100% Class 4.

Trinity – FWP (Plan C):

TY0 0.60 Same as FWOP

TY1 0.63 8% Class 1; 92% Class 3. This includes 520 acres of the proposed marsh

template (Class 3) and 44 acres of other intertidal habitat (Class 1). It was

assumed that the proposed marsh template would function as new

confined carpet marsh with retention dikes that would temporarily prevent

the formation tidal canals. Therefore, the marsh template was assigned a

Class 3 rating. There are no existing mangrove stands on Trinity Island.

TY5 1.00 100% Class 1. It was assumed that retention dikes constructed for the

proposed marsh template would degrade, thus providing tidal access.

Therefore the proposed marsh template was assigned a Class 1 rating. The

remaining intertidal habitat was also assigned a Class 1 rating because it

was assumed to have optimal interspersion.

TY10 0.99 98% Class 1; 2% Class 3

TY20 0.82 12% Class 1; 88% Class 2. The Class 3 habitat from TY10 is expected to

be converted to open water.

TY30 0.63 7% Class 1; 93% Class 3.

TY31 0.62 Interpolated

TY40 0.41 3% Class 3; 97% Class 4.

TY50 0.40 100% Class 4.

Trinity – FWP (Plan C) with renourishment at TY25:

TY0 0.60 Same as FWOP

TY1 0.63 8% Class 1; 92% Class 3. This includes 520 acres of the proposed marsh

template (Class 3) and 44 acres of other intertidal habitat (Class 1). It was

assumed that the proposed marsh template would function as new

confined carpet marsh with retention dikes that would temporarily prevent

the formation tidal canals. Therefore, the marsh template was assigned a

Class 3 rating. There are no existing mangrove stands on Trinity Island.

TY5 1.00 100% Class 1. It was assumed that retention dikes constructed for the

proposed marsh template would degrade, thus providing tidal access.

Therefore the proposed marsh template was assigned a Class 1 rating. The

remaining intertidal habitat was also assigned a Class 1 rating because it

was assumed to have optimal interspersion.

TY10 0.99 98% Class 1; 2% Class 3

TY20 0.82 12% Class 1; 88% Class 2. The Class 3 habitat from TY10 is expected to

be converted to open water.

TY25 0.83 13% Class 1; 87% Class 2.

TY26 0.61 3% Class 1; 97% Class 3. The Class 2 habitat from TY25 is converted to

Class 3. There is a small amount of Class 1 habitat remaining. The dune

and supratidal portions of the island are renourished at TY26. However,

this will not have an immediate impact on interspersion since it does not

immediately affect intertidal habitat.


A-46

TY30 0.63 7% Class 1; 93% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat.

TY40 0.41 4% Class 3; 96% Class 4.

TY50 0.40 100% Class 4.

East – FWOP

TY0 0.60 100% Class 3. Aerial photography indicates the development of larger

open water areas within the intertidal zone.

TY1 0.60 100% Class 3

TY5 0.60 98% Class 3; 2% Class 4

TY10 0.48 41% Class 3; 59% Class 4

TY20 0.40 100% Class 4

TY22 0.40 100% Class 4

TY29 0.40 100% Class 4

TY30 0.40 100% Class 4

TY40 0.10 100% Class 5 (no subaerial habitat)

TY50 0.10 100% Class 5 (no subaerial habitat)

East – FWP (Plan B):

TY0 0.60 Same as FWOP

TY1 0.63 6% Class 1; 94% Class 3. This includes the 339-acre proposed marsh

template (Class 3) and 23 acres of other intertidal habitat. It was assumed

that the proposed marsh template would function as new confined carpet

marsh with retention dikes that would temporarily prevent the formation

tidal canals. Therefore, the marsh template was assigned a Class 3 rating.

There are no existing mangrove stands on East Island.

TY5 1.00 100% Class 1. It was assumed that retention dikes constructed for the

proposed marsh template would degrade, thus providing tidal access.

Therefore the proposed marsh template was assigned a Class 1 rating. The

remaining intertidal habitat was also assigned a Class 1 rating because it

was assumed to have optimal interspersion.

TY10 1.00 100% Class 1

TY20 0.83 15% Class 1; 85% Class 2

TY22 0.79 Interpolated

TY29 0.64 Interpolated

TY30 0.62 4% Class 1; 96% Class 3

TY40 0.40 100% Class 4

TY50 0.40 100% Class 4

Wine – FWOP

TY0 0.40 100% Class 4. Aerial photography indicates extremely fragmented marsh

within and adjacent to the rock ring. There is very little subaerial habitat

present (6 acre)

TY1 0.40 100% Class 4

TY5 0.40 100% Class 4

TY10 0.40 100% Class 4


A-47

TY20 0.40 100% Class 4

TY29 0.40 100% Class 4

TY30 0.40 100% Class 4

TY35 0.10 100% Class 5 (no subaerial habitat)

TY40 0.10 100% Class 5 (no subaerial habitat)

TY50 0.10 100% Class 5 (no subaerial habitat)

Wine – FWP (Plan B):

TY0 0.40 Same as FWOP

TY1 0.77 43% Class 1; 57% Class 3. This includes 55 acres of the proposed marsh

template (Class 3) and 42 acres of other intertidal habitat. It was assumed

that the proposed marsh template would function as new confined carpet

marsh with retention dikes that would temporarily prevent the formation

tidal canals. Therefore, the marsh template was assigned a Class 3 rating.

The total marsh template is 69 acres. However, 14 acres of the template

was constructed in the supratidal zone. Once this portion subsides, it will

be accounted for in the interspersion variable. There are no existing

mangrove stands on Wine Island.

TY5 0.92 80% Class 1; 20% Class 3. It was assumed that retention dikes constructed

for the proposed marsh template would degrade, thus providing tidal

access. Therefore the proposed marsh template was assigned a Class 1

rating. By TY5, a total of 64 acres of the proposed marsh template are

intertidal. Approximately 23 acres and 22 acres of the remaining intertidal

habitat were assigned a Class 1 and Class 3 rating, respectively.

TY10 0.85 59% Class 1; 13% Class 2; 21% Class 3; 7% Class 4

TY20 0.81 23% Class 1; 61% Class 2; 14% Class 3; 2% Class 4

TY29 0.73 Interpolated

TY30 0.72 30% Class 1; 70% Class 3. By TY30, all 69 acres of the proposed marsh

template are intertidal.

TY35 0.67 Interpolated

TY40 0.63 14% Class 2; 86% Class 3

TY50 0.40 100% Class 4. There is very little subaerial habitat present (5 acre)

Timbalier – FWOP

TY0 0.60 100% Class 3. Aerial photography indicates the development of larger

open water areas within the intertidal zone.

TY1 0.60 100% Class 3.

TY5 0.51 57% Class 3; 43% Class 4.

TY10 0.40 100% Class 4.

TY20 0.54 69% Class 3; 31% Class 4. A large slug of supratidal becomes intertidal at

this point. Therefore, the suitability index for dispersion is expected to

increase

TY30 0.50 51% Class 3; 49% Class 4.

TY40 0.40 100% Class 4.

TY41 0.40 100% Class 4.

TY50 0.40 100% Class 4.


A-48

Timbalier – FWP (Plan B):

TY0 0.60 Same as FWOP.

TY1 0.65 13% Class 1; 87% Class 3. This includes the 630-acre proposed marsh

template (Class 3) and 96 acres of other intertidal habitat. It was assumed

that the proposed marsh template would function as new confined carpet

marsh with retention dikes that would temporarily prevent the formation

tidal canals. Therefore, the marsh template was assigned a Class 3 rating.

TY5 1.00 100% Class 1. It was assumed that retention dikes constructed for the

proposed marsh template would degrade, thus providing tidal access.

Therefore the proposed marsh template was assigned a Class 1 rating. The

remaining intertidal habitat was also assigned a Class 1 rating because it

was assumed to have optimal interspersion.

TY10 0.98 96% Class 1; 4% Class 3

TY20 0.85 24% Class 1; 76% Class 2. The Class 3 habitat from TY10 is expected to

covert to open water.

TY30 0.64 9% Class 1; 91% Class 3.

TY40 0.43 4% Class 1; 96% Class 4

TY41 0.42 Interpolated

TY50 0.40 100% Class 4.

Timbalier – FWP (Plan E):

TY0 0.60 Same as FWOP.

TY1 1.00 100% Class 1; The design elevations of Plan E are significantly larger than

those of Plan B. The proposed marsh template is constructed at an

elevation greater than +2 ft NAVD 88 and therefore is not considered to

be intertidal habitat. The proposed marsh template is not expected to be

converted to intertidal habitat until TY30. At TY1, there is only 69 acres

of intertidal habitat. This habitat was assumed to have optimal

interspersion (Class 1).

TY5 1.00 100% Class 1. This includes 71 acres of intertidal habitat.

TY10 1.00 100% Class 1. This includes 74 acres of intertidal habitat.

TY20 1.00 100% Class 1. This includes 76 acres of intertidal habitat.

TY30 0.63 7% Class 1; 93% Class 3. This includes the 1064-acre proposed marsh

template and the remaining 84 acres of intertidal area. The proposed

marsh template is converted to intertidal habitat at TY30 due to

subsidence. Since the marsh template has been at a higher elevation, tidal

inlets have not yet formed. Therefore, the marsh template was assigned a

Class 3 rating. The remaining intertidal area was assigned a Class 1 rating

since it was assumed to have optimal interspersion.

TY40 1.00 100% Class 1. It was assumed that tidal channels would have formed in

the proposed marsh template by TY40. Therefore the proposed marsh

template was assigned a Class 1 rating. The remaining intertidal habitat

was also assigned a Class 1 rating because it was assumed to have optimal

interspersion.

TY41 0.96 Interpolated


A-49

TY50 0.60 100% Class 3.

Timbalier – FWP (Plan E) with renourishment at TY30:

TY0 0.60 Same as FWOP.

TY1 1.00 100% Class 1; The design elevations of Plan E are significantly larger than

those of Plan B. The proposed marsh template is constructed at an

elevation greater than +2 ft NAVD 88 and therefore is not considered to

be intertidal habitat. The proposed marsh template is not expected to be

converted to intertidal habitat until TY30. At TY1, there is only 69 acres

of intertidal habitat. This habitat was assumed to have optimal

interspersion (Class 1).

TY5 1.00 100% Class 1. This includes 71 acres of intertidal habitat.

TY10 1.00 100% Class 1. This includes 74 acres of intertidal habitat.

TY20 1.00 100% Class 1. This includes 76 acres of intertidal habitat.

TY30 0.63 7% Class 1; 93% Class 3. This includes the 1064-acre proposed marsh

template and the remaining 84 acres of intertidal area. The proposed

marsh template is converted to intertidal habitat at TY30 due to

subsidence. Since the marsh template has been at a higher elevation, tidal

inlets have not yet formed. Therefore, the marsh template was assigned a

Class 3 rating. The remaining intertidal area was assigned a Class 1 rating

since it was assumed to have optimal interspersion.

TY31 0.61 3% Class 1; 97% Class 3. The dune and supratidal portions of the island

are renourished at TY31. However, this will not have an immediate impact

on interspersion since it does not immediately affect intertidal habitat.

TY40 1.00 100% Class 1. It was assumed that tidal channels would have formed in

the proposed marsh template by TY40. Therefore the proposed marsh

template was assigned a Class 1 rating. The remaining intertidal habitat

was also assigned a Class 1 rating because it was assumed to have optimal

interspersion.

TY50 0.60 100% Class 3.

East Timbalier – FWOP

TY0 0.60 100% Class 3. Aerial photography indicates the development of larger

open water areas within the intertidal zone.

TY1 0.60 100% Class 3.

TY5 0.60 100% Class 3.

TY10 0.52 61% Class 39% Class 4.

TY20 0.48 38% Class 3; 62% Class 4.

TY30 0.40 100% Class 4.

TY40 0.40 100% Class 4.

TY43 0.40 100% Class 4.

TY45 0.40 100% Class 4.

TY50 0.40 100% Class 4. There is only 4 acres of subaerial habitat remaining.


A-50

East Timbalier – FWP (Plan B):

TY0 0.60 Same as FWOP

TY1 0.69 22% Class 1; 78% Class 3. This includes the 353-acre proposed marsh

template (Class 3) and 99 acres of other intertidal habitat (Class 1). It was

assumed that the proposed marsh template would function as new

confined carpet marsh with retention dikes that would temporarily prevent

the formation tidal canals. Therefore, the marsh template was assigned a

Class 3 rating.

TY5 0.96 90% Class 1; 10% Class 3. It was assumed that retention dikes constructed

for the proposed marsh template would degrade, thus providing tidal

access. Therefore the proposed marsh template was assigned a Class 1

rating. Approximately 78 acres and 45 acres of the remaining intertidal

habitat was assigned a Class 1 and Class 3, respectively.

TY10 0.94 84% Class 1; 16% Class 3

TY20 0.82 17% Class 1; 77% Class 2; 6% Class 3

TY30 0.69 23% Class 1; 77% Class 3. A large slug of supratidal habitat is converted

to intertidal habitat at this point, thus increasing the percentage of Class 1

habitat.

TY40 0.48 13% Class 1; 87% Class 4

TY43 0.45 Interpolated

TY45 0.43 Interpolated

TY50 0.40 100% Class 4. There is only 7 acres of subaerial habitat remaining.

V7- Beach/Surf Zone Features

Raccoon – FWOP

TY0 0.945 There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The total length of the island

was 16,000 ft (source: 2008 USGS aerial).

The island will continue to erode away from the breakwaters due to

natural processes. According to the modeling results, the existing 16

breakwaters will be too far from the island to be effective by TY21. We

assumed that none of the existing breakwaters would be maintained.

For TY0, there are a total of 8820 ft of breakwaters (4400 + 4420), which

is 55% of the beach length. Therefore, 55% of the beach is classified as

Class 3 (breakwaters) and the remaining 45% is classified as Class 1

(unconfined beach). The resulting suitability index is calculated as

follows: (0.55*0.9)+(0.45*1)=0.945

TY1 0.945


A-51

TY5 0.945

TY21 1.00 Since the existing breakwater fields are no longer effective at TY21, the

entire beach is classified as Class 1 (unconfined beach) with a suitability

index of 1.

TY30 1.00

TY40 0.10 There are no subaerial acres at this point; therefore the island is given a

Class 5 rating (No emergent habitat). The suitability index is 0.1.

TY48 0.10

TY50 0.10

Raccoon – FWP (Plan B)

TY0 0.945 There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The total length of the island

was 16,000 ft (source: 2008 USGS aerial).

The island will continue to erode away from the breakwaters due to

natural processes. According to the modeling results, the existing 16

breakwaters will be too far from the island to be effective by TY21. We

assumed that none of the existing breakwaters would be maintained.

For TY0, there are a total of 8820 ft of breakwaters (4400 + 4420), which

is 55% of the beach length. Therefore, 55% of the beach is classified as

Class 3 (breakwaters) and the remaining 45% is classified as Class 1

(unconfined beach). The resulting suitability index is calculated as

follows: (0.55*0.9)+(0.45*1)=0.945

TY1 0.945

TY5 0.945

TY21 1.00 Since the existing breakwater fields are no longer effective at TY21, the

entire beach is classified as Class 1 (unconfined beach) with a suitability

index of 1.

TY30 1.00

TY40 1.00

TY48 1.00

TY50 1.00

Raccoon – FWP (Plan B) with breakwaters

TY0 0.945 There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The total length of the island

was 16,000 ft (source: 2008 USGS aerial).


A-52

The island will continue to erode away from the breakwaters due to

natural processes. According to the modeling results, the existing 16

breakwaters will be too far from the island to be effective by TY21. We

assumed that none of the existing breakwaters would be maintained.

For TY0, there are a total of 8820 ft of breakwaters (4400 + 4420), which

is 55% of the beach length. Therefore, 55% of the beach is classified as

Class 3 (breakwaters) and the remaining 45% is classified as Class 1

(unconfined beach). The resulting suitability index is calculated as

follows: (0.55*0.9)+(0.45*1)=0.945

TY1 0.917 There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The island will erode away

from the breakwaters due to natural processes. According to the modeling

results, the existing 16 breakwaters will be too far from the island to be

effective by TY21. We assumed that none of the existing breakwaters

would be maintained.

A third breakwater field has been proposed as part of this project. The

breakwater field will consist of 8 additional breakwaters, with a

cumulative length of 4500 feet (including gaps). The construction of the

breakwaters will be completed by 2013. It was assumed that typical

maintenance would be conducted as necessary on the breakwaters in order

to maintain their effectiveness. However, the modeling results indicated

that the proposed breakwaters would be too far from the islands to be

effective by TY21 due to natural erosion processes. Therefore,

maintenance of the structures would no longer be effective.

The total length of the island is 16,000 ft (source: 2008 USGS aerial).

For TY1, there are a total of 13320 ft of breakwaters (4400 + 4420 +

4500), which is 83% of the beach length. Therefore, 83% of the beach is

classified as Class 3 (breakwaters) and the remaining 17% is classified as

Class 1 (unconfined beach). The resulting suitability index is calculated as

follows: (0.83*0.9)+(0.17*1)=0.917

TY5 0.917

TY21 1.00 Since the existing breakwater fields are no longer effective at TY21, the

entire beach is classified as Class 1 (unconfined beach) with a suitability

index of 1.

TY30 1.00

TY40 1.00

TY48 1.00

TY50 1.00


A-53

Raccoon – FWP (Plan B) with terminal groin

TY0 0.945 There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The total length of the island

was 16,000 ft (source: 2008 USGS aerial).

The island will continue to erode away from the breakwaters due to

natural processes. According to the modeling results, the existing 16

breakwaters will be too far from the island to be effective by TY21. We

assumed that none of the existing breakwaters would be maintained.

For TY0, there are a total of 8820 ft of breakwaters (4400 + 4420), which

is 55% of the beach length. Therefore, 55% of the beach is classified as

Class 3 (breakwaters) and the remaining 45% is classified as Class 1

(unconfined beach). The resulting suitability index is calculated as

follows: (0.55*0.9)+(0.45*1)=0.945

TY1 0.90 Based on the modeling results for SBEACH, the entire beach was

impacted by either the proposed terminal groin or the 16 existing hard

structures. Therefore, the length of beach impacted by the terminal groins

was calculated by subtracting as follows: 16,000 - 4400 - 4420 = 7180.

There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The island will erode away

from the breakwaters due to natural processes. According to the modeling

results, the existing 16 breakwaters will be too far from the island to be

effective by TY21. We assumed that none of the existing breakwaters

would be maintained.

A terminal groin will be constructed at the western end of the island as

part of this project. The terminal groin will impact approximately 7180 ft

of the shoreline (based on the GENESIS modeling results). It was also

assumed that the terminal groin would impact the surf zone habitat similar

to a breakwater and would thus be assigned a Class 3 rating. The

construction of the terminal groin will be completed by 2013. It was

assumed that the terminal groin would no longer be effective at TY21.

The total length of the island is 16,000 ft (source: 2008 USGS aerial).

For TY1, the entire length of the beach will be impacted by the terminal

groin and the existing breakwaters. Therefore, 100% of the beach is


A-54

classified as Class 3 (breakwaters). The resulting suitability index is

calculated as follows: (1.0*0.9) = 0.9

TY5 0.90 For TY5, the entire length of the beach will be impacted by the terminal

groin and the existing breakwaters. Therefore, 100% of the beach is

classified as Class 3 (breakwaters). The resulting suitability index is

calculated as follows: (1.0*0.9) = 0.9

TY21 1.00 Since the existing breakwater fields are no longer effective at TY21, the

entire beach is classified as Class 1 (unconfined beach) with a suitability

index of 1.

TY30 1.00

TY40 1.00

TY48 1.00

TY50 1.00

Raccoon – FWP (Plan E) with terminal groin

TY0 0.945 There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The total length of the island

was 16,000 ft (source: 2008 USGS aerial).

The island will continue to erode away from the breakwaters due to

natural processes. According to the modeling results, the existing 16

breakwaters will be too far from the island to be effective by TY21. We

assumed that none of the existing breakwaters would be maintained.

For TY0, there are a total of 8820 ft of breakwaters (4400 + 4420), which

is 55% of the beach length. Therefore, 55% of the beach is classified as

Class 3 (breakwaters) and the remaining 45% is classified as Class 1

(unconfined beach). The resulting suitability index is calculated as

follows: (0.55*0.9)+(0.45*1)=0.945

TY1 0.90 Based on the modeling results for SBEACH, the entire beach was

impacted by either the proposed terminal groin or the 16 existing hard

structures. Therefore, the length of beach impacted by the terminal groins

was calculated by subtracting as follows: 16,000 - 4400 - 4420 = 7180.

There are two existing breakwater fields. The first was implemented in

1997 and includes 8 breakwaters. The total length of this breakwater field

is 4400 ft (including gaps) (source: PIS for TE-48). Eight additional

breakwaters were constructed in 2005. This additional breakwater field

was 4420 feet long (source: PIS for TE-48). The island will erode away

from the breakwaters due to natural processes. According to the modeling

results, the existing 16 breakwaters will be too far from the island to be

effective by TY21. We assumed that none of the existing breakwaters

would be maintained.


A-55

A terminal groin will be constructed at the western end of the island as

part of this project. The terminal groin will impact approximately 7180 ft

of the shoreline (based on the GENESIS modeling results). It was also

assumed that the terminal groin would impact the surf zone habitat similar

to a breakwater and would thus be assigned a Class 3 rating. The

construction of the terminal groin will be completed by 2013. It was

assumed that the terminal groin would no longer be effective at TY21.

The total length of the island is 16,000 ft (source: 2008 USGS aerial).

For TY1, the entire length of the beach will be impacted by the terminal

groin and the existing breakwaters. Therefore, 100% of the beach is

classified as Class 3 (breakwaters). The resulting suitability index is

calculated as follows: (1.0*0.9) = 0.9

TY5 0.90 For TY5, the entire length of the beach will be impacted by the terminal

groin and the existing breakwaters. Therefore, 100% of the beach is

classified as Class 3 (breakwaters). The resulting suitability index is

calculated as follows: (1.0*0.9) = 0.9

TY30 1.00 Since the terminal groin and the existing breakwater fields are no longer

effective at TY21, the entire beach is classified as Class 1 (unconfined

beach) with a suitability index of 1.

TY40 1.00

TY50 1.00

Whiskey – FWOP

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY10 1.00

TY17 1.00

TY20 1.00

TY30 1.00

TY50 0.10 There are no subaerial acres at this point; therefore the island is given a

Class 5 rating (No emergent habitat). The suitability index is 0.1.

Whiskey – FWP (Plan B)

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY10 1.00

TY17 1.00

TY20 1.00

TY30 1.00


A-56

TY50 1.00

Whiskey – FWP (Plan C)

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY10 1.00

TY17 1.00

TY20 1.00

TY30 1.00

TY50 1.00

Trinity – FWOP

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY24

TY33 1.00

TY40 0.10 There are no subaerial acres at this point; therefore the island is given a

Class 5 rating (No emergent habitat). The suitability index is 0.1.

TY50 0.10

Trinity – FWP (Plan B)

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY24 1.00

TY33 1.00

TY40 1.00

TY50 1.00

Trinity – FWP (Plan C)

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY31 1.00

TY40 1.00

TY50 1.00


A-57

East – FWOP

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY22 1.00

TY29 1.00

TY40 0.10 There are no subaerial acres at this point; therefore the island is given a

Class 5 rating (No emergent habitat). The suitability index is 0.1.

TY50 0.10

East – FWP (Plan B)

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY22 1.00

TY29 1.00

TY40 1.00

TY50 1.00

Wine – FWOP

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY29 1.00

TY35 0.10 There are no subaerial acres at this point; therefore the island is given a

Class 5 rating (No emergent habitat). The suitability index is 0.1.

TY40 0.10

TY50 0.10

Wine w/Monkey – FWP (Plan B)

TY0 1.00 100% Class 1; Unconfined natural beach with no structures parallel to the

shore.

TY1 1.00

TY5 1.00

TY20 1.00

TY29 1.00

TY35 1.00

TY40 1.00

TY50 1.00


A-58

Timbalier – FWOP

TY0 0.96 There is an existing seawall that is approximately 1,900 ft long. The

seawall is on the beach and acts as a revetment (Class 4). The total island

length is 35,570 ft long. Therefore 5.3% of the island will be assigned a

Class 4 rating (Seawall - SI = 0.2) and the remaining portion of the island

will be assigned a Class 1 (SI = 1) rating. The suitability index is

calculated as follows: (0.053 * 0.2)+(0.947 * 1) = 0.96

TY1 0.96

TY5 0.96

TY20 1.00 By TY20, the portion of the island that is behind the seawall completely

washes away. Although the wall is expected to still be intact, it will not be

effecting surf zone habitat. 100% Class 1; Unconfined natural beach with

no structures parallel to the shore

TY41 1.00

TY50 1.00

Timbalier – FWP (Plan B)

TY0 0.96 There is an existing seawall that is approximately 1,900 ft long. The

seawall is on the beach and acts as a revetment (Class 4). The total island

length is 35,570 ft long. Therefore 5.3% of the island will be assigned a

Class 4 rating (Seawall - SI = 0.2) and the remaining portion of the island

will be assigned a Class 1 (SI = 1) rating. The suitability index is

calculated as follows: (0.053 * 0.2)+(0.947 * 1) = 0.96

TY1 0.96

TY5 0.96

TY20 0.99 There is an existing seawall that is approximately 1,900 ft long. The

seawall that was on the beach is expected to be in the surf zone by TY20,

due to island migration. Therefore, it will likely function as a breakwater

(Class 3). The total island length is 39,630 ft long. Therefore 4.8% of the

island will be assigned a Class 3 rating (SI = 0.9) and the remaining

portion of the island will be assigned a Class 1 (SI = 1) rating. The

suitability index is calculated as follows: (0.048 * 0.9)+(0.952 * 1) = 0.99

TY41 0.99

TY50 0.99

Timbalier – FWP (Plan E)

TY0 0.96 There is an existing seawall that is approximately 1,900 ft long. The

seawall is on the beach and acts as a revetment (Class 4). The total island

length is 35,570 ft long. Therefore 5.3% of the island will be assigned a

Class 4 rating (Seawall - SI = 0.2) and the remaining portion of the island

will be assigned a Class 1 (SI = 1) rating. The suitability index is

calculated as follows: (0.053 * 0.2)+(0.947 * 1) = 0.96

TY1 0.96

TY5 0.96

TY20 0.99 There is an existing seawall that is approximately 1,900 ft long. The

seawall that was on the beach is expected to be in the surf zone by TY20,


A-59

due to island migration. Therefore, it will likely function as a breakwater

(Class 3). The total island length is 39,630 ft long. Therefore 4.8% of the

island will be assigned a Class 3 rating (SI = 0.9) and the remaining

portion of the island will be assigned a Class 1 (SI = 1) rating. The

suitability index is calculated as follows: (0.048 * 0.9)+(0.952 * 1) = 0.99

TY41 0.99

TY50 0.99

East Timbalier – FWOP

TY0 0.54 Approximately 49% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 51% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.49*0.9)+(0.51*0.2) =

0.54

TY1 0.54

TY5 0.54

TY10 0.58 Approximately 54% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 46% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.54*0.9)+(0.46*0.2) =

0.58

TY20 0.87 Approximately 96% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 4% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.96*0.9)+(0.04*0.2) =

0.87

TY43 0.90

TY45 0.90

TY50 0.90

East Timbalier – FWP (Plan B)

TY0 0.54 Approximately 49% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 51% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.49*0.9)+(0.51*0.2) =

0.54

TY1 0.69 Approximately 70% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 30% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.7*0.9)+(0.3*0.2) = 0.69

TY5 0.70 Approximately 71% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 29% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.71*0.9)+(0.29*0.2) =

0.70


A-60

TY10 0.71 Approximately 72% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 28% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.72*0.9)+(0.28*0.2) =

0.71

TY20 0.88 Approximately 98% of the island is protected by breakwaters (TE-25, TE30, or the existing rock wall that is now offshore), while 2% is protected

by a portion of the rockwall that is now on the beach, functioning as a

revetment. The SI was calculated as follows: (0.98*0.9)+(0.02*0.2) =

0.88

TY43 0.90 Approximately 100% of the island is protected by breakwaters (TE-25,

TE-30, or the existing rock wall that is now offshore). The SI was

calculated as follows: (1.0*0.9) = 0.9

TY45 0.90

TY50 0.90










TERREBONNE BASIN BARRIER

SHORELINE RESTORATION

DRAFT FISH AND WILDLIFE

COORDINATION ACT REPORT

April 30, 2010
















































































APPENDIX C

NOAA FISHERIES SERVICE

COORDINATION LETTER









APPENDIX D

404(b)(1) WATER QUALITY REPORT



1

Volume IV

APPENDIX D:

404(b)(1) Water Quality Report

1.0 Project Description

1.1 Location and General Description

The project, located in LCA Subprovince 3, provides for the restoration of the Timbalier

and Isles Dernieres Barrier Island chains located in Terrebonne and Lafourche Parishes,

Louisiana. The study area (Figure 1) is located in the 3rd Congressional District. The

study area consists of the barrier islands being considered for restoration as well as the

offshore borrow areas. The borrow areas are depicted on Figure 2.

Isles Dernieres Reach

The Isles Dernieres Reach represents a barrier island arc approximately 22 miles long in

the southern reaches of Terrebonne Parish and extends from Caillou Bay east to Cat

Island Pass. Raccoon, Whiskey, Trinity, East, and Wine, the primary islands that

comprise the Isles Dernieres barrier island chain, are backed by Bay Blanc, Bay Round,

Caillou Bay and Terrebonne Bay, and bordered by the Gulf of Mexico (GOM) on the

seaward side. The remnant of Wine Island is located in Wine Island Pass, about midway

between East and Timbalier Islands.

Timbalier Reach

The Timbalier Reach is comprised of Timbalier Island and East Timbalier Island.

Timbalier and East Timbalier Islands are on the western edge of the Lafourche barrier

shoreline and are located about 60 miles southwest of New Orleans, Louisiana. This

barrier island shoreline is approximately 20 miles long and backed by Terrebonne and

Timbalier Bay to the north and delimited by Raccoon Pass to the east and Cat Island Pass

to the west. The islands range from 0.1 to 0.6 miles wide, with low elevations.

Borrow Areas

Ship Shoal is the largest and easternmost of a series of sand shoals on the inner

continental shelf of Louisiana and contains approximately 1.6 billion cubic yards of fine

sand. The elongated shoal lies parallel to the coast approximately 8 to 12 miles (12 to 19

km) south of the Isles Dernieres Reach and measures approximately 31 miles (50 km) in

an east-west direction. The potential borrow areas identified within the shoal include Ship

Shoal MMS Lease Blocks 87, 88, 89, 94 (Ship Shoal) and South Pelto Blocks 12, 13, 14,

18, and 19 (South Pelto).


2

Several closer sand sources, previously identified for other coastal restoration project will

also be used for construction of the NER. These include: Whiskey Island Restoration

Borrow Area 3a (Whiskey Island), New Cut TE-37 Borrow Area (New Cut), and

Raccoon Island TE-48 Borrow Area (Raccoon Island). These proposed borrow areas are

shown on Figure 2.

Figure 1. Terrebonne Basin Barrier Shoreline Restoration Study Area.


3

Figure 2. Proposed Borrow Areas.

1.2 Authority and Purpose

Title VII of the Water Resources Development Act (WRDA) 2007 authorizes the

Louisiana Coastal Area (LCA) ecosystem restoration program. Included within that

authority are requirements for comprehensive coastal restoration planning, program

governance, a Science and Technology Program, a program for the beneficial use of

dredged material, feasibility studies for restoration plans, project modification

investigations, and restoration project construction, in addition to other program

elements. This authorization was recommended by the Chief of Engineer’s Report, dated

January 31, 2005.

Under the 2007 WRDA Section 7006, the LCA program has authority for feasibilitylevel reports of six near-term critical restoration features. The excerpt below from

WRDA outlines the project authority for this report for the Terrebonne Basin Barrier

Shoreline Restoration project:

SEC. 7003. LOUISIANA COASTAL AREA.

(a) IN GENERAL.-The Secretary may carry out a program for ecosystem restoration, Louisiana

Coastal Area, Louisiana, substantially in accordance with the report of the Chief of Engineers,

dated January 31, 2005.

SEC. 7006. CONSTRUCTION.


4

(3) PROJECTS SUBJECT TO REPORTS.—

(A) FEASIBILITY REPORTS.—Not later than December

31, 2008, the Secretary shall submit to Congress feasibility

reports on the following projects referred to in the restoration

plan:

(i) Multipurpose Operation of Houma Navigation

Lock at a total cost of $18,100,000.

(ii) Terrebonne Basin Barrier Shoreline Restoration

at a total cost of $124,600,000.

(iii) Small Diversion at Convent/Blind River at a

total cost of $88,000,000.

(iv) Amite River Diversion Canal Modification at a

total cost of $5,600,000.

(v) Medium Diversion at White’s Ditch at a total

cost of $86,100,000.

(vi) Convey Atchafalaya River Water to Northern

Terrebonne Marshes at a total cost of $221,200,000.

(B) CONSTRUCTION.—The Secretary may carry out the

projects under subparagraph (A) substantially in accordance

with the plans and subject to the conditions, recommended

in a final report of the Chief of Engineers if a

favorable report of the Chief is completed by not later than

December 31, 2010.

(4) CONSTRUCTION.—No appropriations shall be made to

construct any project under this subsection if the report under

paragraph (2) or paragraph (3), as the case may be, has not

been approved by resolutions adopted by the Committee.

This report is an integrated feasibility study and environmental impact statement (EIS)

conducted for the Terrebonne Basin Barrier Shoreline Restoration project. This report

fulfills the reporting requirement to Congress of Section 7006(e)(3) which directs the

Secretary of the Army to submit feasibility reports on the six projects included in that

section by December 31, 2008 and authorizes implementation of the projects provided a

favorable Chief of Engineers’ Report is completed no later than December 31, 2010.

The National Ecosystem Restoration Plan (NER Plan) includes the restoration of

Raccoon Island to its minimal geomorphologic form and ecologic function along with

twenty-five (25) years of advanced fill (Plan E) and construction of a terminal groin.

This plan also includes restoration of Whiskey and Trinity Islands to their minimal

geomorphologic form and ecologic function along with five (5) years of advanced fill

(Plan C) and restoration of Timbalier Island to its minimal geomorphologic form and

ecologic function along with twenty-five (25) years of advanced fill (Plan E).

Approximately 5,840 acres would be restored for the NER Plan.

1.3 General Description of Excavated or Dredged and Fill Material

General Characteristics of Material. The materials proposed for placement on

Raccoon, Whiskey, Trinity, and Timbalier Islands consist of sands, silts, and clays

materials.


5

Quantity and Source of Dredged Material.

The NER plan will require a total of 55,787,481 cy of dredged material for initial

construction and 23,639,786 cubic yards for periodic renourishment. Table 1 provides

detailed information on the cut and fill quantities for the NER. Table 2 contains total

volumes that will be dredged from each of the borrow areas during initial construction

and renourishment. Figure The following sections provide additional information on the

source and quantity of material that will be dredged for each component of NER Plan.

Whiskey Island Plan C

Whiskey Island Plan C has been proposed as the first component of construction. During

construction, approximately 8.3 mcy of sandy material would be placed along the

southern beach shoreline and dune of Whiskey Island. Approximately 0.6 mcy of marsh

material would be placed within the marsh template of the site.

The island will also require two renourishment intervals in order to maintain its

geomorphologic form and ecologic function throughout the 50-year period of analysis.

The first renourishment event will occur 20 years after construction (i.e. 2032) and will

include the addition of approximately 8.3 mcy of sandy material to the dune and

supratidal beach components of the island. The second renourishment interval will occur

40 years after construction (i.e. 2052) and will include the addition of approximately 6.4

mcy of sandy material to the dune and supratidal beach. No additional marsh material

will be added.

The material used for the initial construction of Whiskey Island Plan C will be dredged

from the Ship Shoal Borrow Area and Whiskey Island Restoration Borrow Area 3. The

material used for the renourishment events at TY20 and TY40 will also be dredge from

the Ship Shoal Borrow Area.

Raccoon Island Plan E with Terminal Groin

Fill quantities for the dune/beach and marsh components of Raccoon Plan E are 5.4

million and 4.6 mcy, respectively. The plan will utilize beach/dune material from Ship

Shoal and marsh material from the Raccoon Island TE-48 borrow area. However, the

borrow area does not have enough material to construct the marsh in its entirety.

Therefore, approximately 2.8 mcy of sand will be dredged from Ship Shoal to provide a

base layer for the marsh. The marsh material from the Raccoon Island TE-48 borrow

area will be deposited on the sand material to provide an adequate foundation for the

marsh.

For the dune area, the material will be pumped from the dredge to the beach. The

material will then be worked on the beach by bulldozers and front-end loaders. For the

marsh area, the material will be pumped from the offshore borrow site. Containment

dikes will be constructed around the perimeter. Sediment for the containment dikes will

be dredged from existing material inside the marsh creation area. These operations will

be completed in a manner that will minimize turbidity of the water at the dredge site and

the discharge site.


6

Trinity Island Plan C

Trinity Plan C will utilize beach/dune material from Ship Shoal and marsh material from

the Whiskey 3A borrow area. Fill quantities for the dune/beach and marsh components

of Trinity Plan C are 3.8 million and 3.8 mcy, respectively. For the dune area, the

material will be pumped from the dredge to the beach. The material will then be worked

on the beach by bulldozers and front-end loaders. For the marsh area, the material will be

pumped from the offshore borrow site. Containment dikes will be constructed around the

perimeter. Sediment for the containment dikes will be dredged from existing material

inside the marsh creation area. These operations will be completed in a manner that will

minimize turbidity of the water at the dredge site and the discharge site.

Timbalier Plan E

Fill quantities for the dune/beach and marsh components of Timbalier Plan E are 10.7

million and 9.1 mcy, respectively. Timbalier Plan E will utilize beach/dune material

from South Pelto and marsh material from Whiskey 3A (marsh material). However, the

marsh borrow areas do not have adequate material to construct the marsh in its entirety.

Therefore, approximately 8.6 mcy of sand will be dredged from South Pelto, Whiskey 3A

(sandy material), and New Cut to provide a base layer for the marsh. The marsh material

from Whiskey 3A will be deposited on the sand material to provide an adequate

foundation for the marsh.

For the dune area, the material will be pumped from the dredge to the beach. The

material will then be worked on the beach by bulldozers and front-end loaders. For the

marsh area, the material will be pumped from the offshore borrow site. Containment

dikes will be constructed around the perimeter. Sediment for the containment dikes will

be dredged from existing material inside the marsh creation area. These operations will

be completed in a manner that will minimize turbidity of the water at the dredge site and

the discharge site.


7

Table 1. Cut and Fill Quantities for Alternative 5 (NER).

Island Fill Template

Fill

Volume

(cy)

Source

Source Fill

Volume

(cy)

Cut-toFill Cut Volume (cy) Depth of Cut Acreage (acres)

Initial Construction

Beach/Dune 5,381,956 Ship Shoal 5,381,956 1.13 6,081,610 12 315

Ship Shoal 2,763,555 1.13 3,122,817 12 162

RaccoonPlan E Marsh 4,609,709

Raccoon 1,846,154 1.3 2,400,000 18 83

Beach/Dune 8,330,215 Ship Shoal 8,330,215 1.13 9,413,143 12 487 Whiskey

Plan C Marsh 579,724 Whiskey (marsh) 579,724 1.6 927,558 12 48

Beach/Dune 3,813,885 Ship Shoal 3,813,885 1.13 4,309,690 12 223 Trinity Plan

C Marsh 3,772,925 Whiskey (marsh) 3,772,925 1.6 6,036,680 12 312

Beach/Dune 10,702,818 South Pelto 10,702,818 1.13 12,094,184 13 577

South Pelto 3,083,736 1.13 3,484,622 13 167Whiskey (beach) 3,630,769 1.3 4,720,000 8 366Whiskey (marsh) 435,735 1.6 697,176 12 37

TimbalierPlan E Marsh 9,073,317

New Cut 1,923,077 1.3 2,500,000 18 87

Renourishment

RaccoonPlan E

Plan B @ TY30 –Beach/Dune 1,946,212 Ship Shoal 1,946,212 1.13 2,199,220 12 114

Plan C @ TY20 –Beach/Dune 8,330,215 Ship Shoal 8,330,215 1.13 9,413,143 12 487 Whiskey

Plan C Plan B @ TY40 –

Beach/Dune 6,359,650 Ship Shoal 6,359,650 1.13 7,186,405 12 372

Trinity Plan C @TY25 – Beach/Dune 3,813,885 Ship Shoal 3,813,885 1.13 4,309,690 12 223TimbalierPlan E

Plan B @ TY30 –Beach/Dune 470,203 South Pelto 470,203 1.13 531,329 13 26


8

Table 2. Borrow Area Utilization for Alternative 5 (NER).

1.4 Description of Proposed Discharge Sites

Location and Size. Initial construction would cover a total of 3,283 acres of water

bottoms and existing fragmented barrier habitats on Raccoon, Whiskey, Trinity, and

Timbalier Islands. Renourishment would directly cover 71 acres on Raccoon, 474 acres at

TY 20 and 349 acres at TY40 on Whiskey Island; 537 acres on Trinity Island at TY 25;

and 202 acres on Timbalier Island at TY30.

Type of Site. The disposal sites for the beach and marsh creation projects are comprised

of shallow open-water and fragmented barrier habitats. All disposal areas are saline and

tidally influenced. Earthen retention dikes would be constructed as needed to span gaps

of open water between sections of barrier habitats or natural ridges within the marsh and

beach creation sites. Material excavated for construction of floatation and access channels

would be placed in shallow open-water between the shoreline and dikes or adjacent to the

excavation channel.

Type of Habitat. The discharge sites consist of typical coastal barrier island habitats

including: shallow intertidal flats, emergent saline marsh, and beach/dune habitat. These

areas provide estuarine habitat that supports marine life of the Gulf of Mexico. Salinity

within the disposal area is high and a variety of marine fauna utilize the area. These

estuarine habitats also function as critical nursery areas for various species of finfish and

shellfish including; brown, white, and pink shrimp; blue crab; oyster; menhaden; black

and red drum; spotted sea trout; sheepshead; striped mullet; and croaker.

Borrow Area Acreage Volume (cy)

Initial Construction

South Pelto 744 15,578,806

Ship Shoal 1,187 22,927,260

Whiskey (12’ depth) 31 Not applicable

Whiskey (20’ depth) 366 12,381,414

New Cut 87 2,500,000

Raccoon Island 83 2,400,000

Renourishment

South Pelto 26 531,329

Ship Shoal 1196 23,108,457


9

Timing and Duration of Discharge. The dredge and fill activities for the NER are

expected to last about 2,480 days. The excavation/dredging activities would occur

simultaneously with placement of previously dredged material to disposal areas.

Description of Disposal Method. Excavation and construction of retention features

within the marsh creation sites would be performed with a marsh buggy equipped with a

bucket, or similar equipment. Dredged material would be excavated from the borrow sites

by a hydraulic cutterhead dredge and discharged from a pipeline into the marsh creation

disposal areas. If practical, other mechanical or hydraulic dredges would be utilized for

placement of material into the disposal areas. A mechanical dredge, such as a bargemounted bucket dredge, would be used to excavate and place the floatation channel

material in the shallow open-water disposal areas. A barge-mounted drag-line with a

bucket, or similar equipment, would be used to construct the shoreline protection dikes.

2.0 Factual Determinations

2.1 Physical Substrate Determinations

Comparison of Existing Substrate and Fill. Sediments at the Terrebonne Basin

Barrier Island Restoration Project – NER Plan project area and the proposed borrow

sites are composed of similar alluvial silts, clays, fine and coarse sands formed by the

deltaic process. However, sediments at the marsh creation disposal areas likely contain

greater amounts of organic material originating from the surrounding marsh. Due to

similar physical qualities of substrates at borrow and marsh creation sites, it is anticipated

that plants from the surrounding marsh would colonize the newly deposited material.

Earthen retention dikes would be constructed from material borrowed from within or

adjacent to the disposal areas, and would not differ from surrounding sediments in the

disposal area.

Changes to Disposal Area Elevation. Shallow open-water disposal areas of the

Terrebonne Basin Barrier Island Restoration Project – NER Plan would be filled to an

initial elevation of approximately +4.2 feet NAVD88 for beach; +6.4 feet NAVD88 for

Dune, and +2.4 feet NAVD88 for marsh. Elevations between +0.5 and +1.5 feet

NAVD88 are expected within the disposal areas following dewatering and compaction,

and would be suitable for marsh development. Earthen retention dikes would be

constructed in open water areas around the perimeter of the disposal areas to elevations of

about +6.0 feet NAVD88. The retention features would degrade naturally over time to

match marsh or open-water elevation.

Migration of Fill. Construction methods may vary but it is anticipated that sand

placement along the shoreline will be controlled by advancing a temporary sand dike

several hundred feet parallel to shore ahead of the discharge terminus. This aids in

reducing initial fill losses offshore and helps control temporary turbidity that may result

from the fill placement operations. Typically water drainage and discharges will be

directed offshore into the Gulf of Mexico or into existing marsh areas to nourish these

habitats.


10

Placement of the material for the backbarrier marsh would be confined to the limits of the

diked area and project footprint.

Duration and Extent of Substrate Change. Substrates at the disposal and borrow sites

are of similar physical quality, and plant colonization at the marsh creation sites would

increase organic content of the newly deposited sediments. The marsh creation areas

would be protected from erosion by containment dikes along the northern edge of the

backbarrier marsh fill area. However, the material is expected to subside over time, and

the disposal areas would convert back to shallow open-water without periodic

maintenance. Earthen retention features are expected to degrade naturally over time after

project completion.

The discharge of floatation and access channel material at the Terrebonne Basin Barrier

Island Restoration Project – Whiskey (Plan C) project into shallow open-water is not

expected to substantially alter disposal area substrates. Substrates at the excavation and

disposal sites are of similar quality. Dredged material placed between the shoreline and

dikes is expected to consolidate and migrate into low-lying areas within or adjacent to the

disposal areas. Total impacted acres are to be determined by the P.E.D at a later date.

Changes to Environmental Quality and Value. Initial construction of the NER would

remove a total of 55,787,481 cy of borrow material from a total of 2,498 acres of water

bottoms in the offshore borrow areas. Renourishment would remove a total of 23,639,786

cy from a total of 1,222 acres of water bottoms in offshore borrow areas. Initial

construction would cover a total of 3,283 acres of water bottoms and existing fragmented

barrier habitats. Renourishment would directly cover 71 acres on Raccoon, 474 acres at

TY 20 and 349 acres at TY40 on Whiskey Island; 537 acres on Trinity Island at TY 25;

and 202 acres on Timbalier Island at TY30.

The NER Plan would initially restore a total of 5,840 acres on Raccoon, Whiskey,

Trinity, and Timbalier Islands. This would include initial restoration of a total of 472

acres of dune, 4,320 acres of supratidal and 1,048 acres of intertidal vegetated habitats

used by fish and wildlife for shelter, nesting, feeding, roosting, cover, nursery, and other

life requirements; increased vegetation growth and productivity; and reduced inter- and

intra-specific species competition between resident and non-resident fish and wildlife

species for limited coastal vegetation. A complete environmental impact assessment can

be found in Section 5 of the Integrated Feasibility Study and Final Environmental Impact

Statement.

Actions to Minimize Impacts. Project construction will require placement of beach and

marsh fill within the Study Area. These activities could potentially adversely impact

cultural resources and threatened and endangered species living within the Project Area.

Cultural resource surveys will be conducted within the Project Area prior to construction

activities in areas where they have not been conducted already. If during dredging,

cultural resources are inadvertently discovered, construction activities will cease and the

USACE shall immediately secure the jobsite. The USACE will immediately notify the


11

State Historic Preservation Office, Indian Tribes, and other consulting parties as

appropriate.

The project could potentially impact threatened and endangered species as well as species

of special interest. To avoid/minimize impacts, construction-related activities will be

coordinated with the USFWS, NMFS, and LDWF. During the PED process, both the

mechanics/ methodologies and phasing of fill placement will be analyzed and modified

with the goal to eliminate or minimize adverse impacts to the species inhabiting the

Project Area. Detailed information regarding protection of threatened and endangered

species and species of special interest is found in the Section 3.7.7.1 of the main report.

2.1.1 Water Circulation, Fluctuation, and Salinity Determination

Normal water fluctuations in the area consist of daily, seasonal, and annual tidal and

flood fluctuations in water level and salinity gradients. Water circulation, stratification,

and chemistry as they relate to the discharge/placement of excavated or previously

dredged material are will not be significantly affected by the proposed action.

Alteration of Current Patterns and Water Circulation. Currents and water circulation

within the disposal areas are influenced primarily by tidal and wind driven forces. The

combined force of wind and tide regulate current direction and velocity along the

shoreline, through narrow bayous, at bayou openings, and within open water areas.

Discharge of dredged material and construction of earthen retention features for the

barrier island restoration project would convert open water areas to low elevation land

inundated only during high tides. Currents or water circulation within these disposal areas

would be minimal and only possible during periodic high tides. Earthen retention features

would be constructed across areas of open water, and would restrict water from moving

into the disposal area or along routes that are currently open to circulation. However, tidal

access would be restored after retention features degrade.

Discharge of floatation channel material between the dikes and shoreline at the shoreline

protection projects would reduce the overall volume and depth of water within the

disposal area, although it is impossible to determine the extent of this reduction. The

reduction of water depth, including the creation of sub-aerial mounds, would further alter

currents and water circulation between the dikes and shoreline. Impacts to water

circulation and depth would be temporary, and conditions similar to pre-construction

levels would return as the dredged material naturally disperses between the shoreline and

dike.

Interference with Water Level Fluctuation. Water level within the marsh creation and

shoreline protection disposal areas is primarily influenced by tidal fluctuation. While the

placement of dredged material and stone at the project sites would decrease overall water

depths within the disposal areas, there would be no interference with water level

fluctuation associated with the tides.


12

Salinity Gradient Alteration. Marsh creation and shoreline protection features or

disposal of floatation/access channel material would not result in any obstruction of flow

from these intersections or other minor bayous. Therefore, alteration of salinity gradients

is not expected.

Cumulative Effects on Water Quality:

Salinity. No cumulative effects are expected.

Clarity. No effects are expected.

Color. No effects are expected.

Water Chemistry and Dissolved Gases. No effects are expected.

Temperature. No effects are expected.

Nutrients. Slight increases in nutrient concentrations may occur; however, these

would rapidly disperse. These described increases would have no significant effect to the

water column.

Changes to Environmental Quality and Value. The direct impacts of implementing

the NER Plan would primarily result from the discharge of 67,184,714 cy of dredged

material and associated effluent waters during construction. Proposed restoration features

would not result in either long-term or short-term water quality impacts to the adjacent

aquatic ecosystem. Potential impacts of dredged material effluent discharges would

include increased turbidity and decreased oxygen concentrations, are expected to be

short-lived and would likely result in temporary and minor impacts to water quality, if

any.

Actions Taken to Minimize Impacts. Containment of dredged material by earthen

retention dikes and natural features within the marsh creation disposal areas would

minimize turbid plumes in adjacent waters. Gaps in the dikes at channel openings would

allow water to circulate between the bays, shallow open-water fronting the shoreline, and

interior marshes.

2.1.2 Suspended Material/Turbidity Determination

Alteration of Suspended Particulate Type and Concentration. Particulates suspended

at the dredging locations and within the disposal areas during project construction, or by

natural forces after project construction, are not expected to differ in type from

particulates currently within the project area.

Particulate Plumes Associated with Discharge. Temporary and local particulate

plumes may occur during construction activities but will quickly dissipate after

construction is complete.


13

Changes to Environmental Quality and Value. Particulate plumes resulting from any

construction activity are not expected to persist after project completion. Particulates

suspended within disposal areas during project construction, or by natural forces after

construction, are not expected to differ in type from particulates currently within the

project area.

Actions to Minimize Impacts. Water column turbidity alterations will be temporary in

nature, taking place during excavation/dredging activity, and are expected to return to

normal once these activities are completed. Minimal impacts would occur if construction

and excavation were timed with low water stages.

2.1.3 Contaminant Determinations

A Phase I Environmental Site Assessment was completed for the project Study Area and

indicated no findings of any HTRW impacts. It is not expected, based on these findings,

that any contaminants will go into suspension during the construction of this project.

2.2 Aquatic Ecosystem and Organisms Determinations

Effects on Plankton. Direct impacts to plankton resources of implementing the NER

Plan would be localized and short-term adverse impacts, including mortality of some

plankton populations, due to construction activities of terminal groin at Raccoon Island,

dredging activities at borrow sites as well as placement of borrow for barrier island

restoration. During initial construction and re-nourishment a total of 1,1048 acres and

1,601 acres, respectively, of water bottoms and fragmented barrier habitat would be

converted to beach, dune and marsh barrier habitats.

During construction, there would be a localized and short-term decrease in available

dissolved oxygen; an increase in turbidity, temperature and biological oxygen demand

(BOD). Following construction and dredging operations, the area would return to

ambient conditions and be re-colonized by plankton populations.

Effects on Benthos. Initial construction would directly impact a total of 2,498 acres of

borrow site water bottoms and benthic organisms utilizing these areas including: 744

acres at the South Pelto-6; 1,187 acres at Ship Shoal-7, 31 acres at Whiskey 3A (12 ft

depth); 366 acres at Whiskey 3A (20 ft depth); 87 acres at New Cut BA-4, and 83 acres at

Raccoon Island BA-5. Renourishment would directly impact a total of 1,222 acres of

borrow site water bottoms and benthic organisms utilizing these areas including 1,196

acres at Ship Shoal - 7 and 26 acres at South Pelto – 6.

A total of 3,283 acres of existing water bottoms would be converted to beach, dune and

marsh barrier habitats during initial construction. Renourishment would impact 1,633

acres of water bottoms and associated benthic organisms.

Dredging and placement of borrow material, as well as placement of rock over 2 acres for

construction of the terminal groin on Raccoon Island, could destroy any slow-moving or


14

sessile benthic organisms found within the borrow areas, within the barrier island

restoration/creation areas, or within the footprint of the terminal groin at Raccoon Island.

However, more mobile benthic species would likely be displaced to more suitable

habitats.

Effects on Nekton. The direct impacts to fisheries resources of implementing the NER

Plan would be localized and short-term adverse impacts due to construction activities of

the terminal groin at Raccoon Island, dredging activities at borrow sites and access

canals, as well as placement of borrow for barrier island restoration. Initial construction

would directly impact a total of 2,498 acres of borrow site water bottoms including 744

acres at the South Pelto-6; 1,187 acres at Ship Shoal-7, 31 acres at Whiskey 3A (12 ft

depth); 366 acres at Whiskey 3A (20 ft depth); 87 acres at New Cut BA-4, and 83 acres at

Raccoon Island BA-5. Renourishment would directly impact a total of 1,222 acres of

borrow site water bottoms including 1,196 acres at Ship Shoal - 7 and 26 acres at South

Pelto – 6.

A total of 3,283 acres of existing water bottoms would be converted to barrier island

transitional habitats. Dredging and placement of borrow material could destroy any slowmoving or sessile fisheries organisms found within the borrow areas and within the

barrier island restoration/creation areas. Sessile or slow moving fisheries resources would

also likely suffer some mortality or injury during placement of rocks a the terminal groin

at Raccoon Island. Construction activities would also temporarily increase turbidity,

temperatures and biological oxygen demand (BOD); and decrease dissolved oxygen.

However, following construction, displaced fisheries resources would likely return to the

Study Area.

Effects on the Aquatic Food Web. All aquatic organisms, in all of their life stages,

could potentially be impacted temporarily during construction activities and placement of

excavated material that would cause increased turbidity and change in water circulation

patterns. Excavation during periods of reproduction/spawning will be minimized or

avoided. Impact to or reduction of detrital feeding species or lower trophic level species

(immobile or sedentary bottom feeders) will be minimized as much as possible to

preserve the food chain populations and nutrient export capability of the ecosystem.

While no adverse cumulative effects on the aquatic organisms are expected to result from

this project, it is expected that some effects will improve and/or benefit aquatic life

within the ecosystem.

Effects on Threatened and Endangered Species. Species that have been found within

the study area that is either considered threatened or endangered include Gulf sturgeon,

green sea turtle, hawksbill sea turtle, Kemp’s Ridley sea turtle, leatherback sea turtle,

loggerhead sea turtle, brown pelican, and the West Indian manatee. Details regarding the

protection of threatened and endangered species are included in Section 3.7.7.1 of the

main report and in the USACE Biological Assessment (Appendix A of main report)

Effects on Other Wildlife. Direct impacts to wildlife and habitat resources of

implementing NER Plan would primarily result from initial construction and renourishment construction activities related to placement of borrow material on existing


15

fragmented dune, supratidal, intertidal (gulfside and bayside) and shallow open water

habitats that would make these habitats temporarily unavailable and could disrupt or

displace wildlife utilizing these habitats. The NER Plan would initially restore a total of

5,840 acres on Raccoon, Whiskey, Trinity, and Timbalier Islands including a total of 472

acres of dune, 4,320 acres of supratidal and 1,048 acres of intertidal wildlife habitats for

use by various wildlife species.

Placement of borrow material would unavoidably bury existing barrier shoreline, dune,

marsh, and shallow water bottom wildlife habitat resources. Following placement,

consolidation of borrow material would take about one year.

Construction of the terminal groin on Raccoon Island would result in 2 acres of these

existing shallow water bottoms to be permanently unavailable for use by wildlife.

Potential impacts to migratory bird and colonial nesting birds are described in Section

5.7.1.2 of the main report and in the USACE Biological Assessment (Appendix A of

main report).

Actions to Minimize Impacts. Due to the duration of the construction events, avoiding

critical nesting periods altogether is not feasible under the current schedule and funding

constraints. The USACE will develop a Nesting Prevention Plan that will include a

combination of proactive measures, coordination, monitoring, and avoidance that will be

utilized to avoid/reduce impacts to these species. Throughout PED, consultation will

continue with the LDWF, USFWS, and NMFS on detailed contract specifications to

avoid and minimize potential impacts to the brown pelican and colonial nesting

waterbirds.

2.3 Special Aquatic Sites

2.3.1 Effect on Sanctuaries and Refuges

The project Study Area is within the Terrebonne Barrier Island Refuge. The purpose,

along with objectives and goals of this project, is to improve the existing degrading

barrier island conditions within the refuge.

2.3.2 Effect on Wetlands

The NER Plan would affect wetlands during the construction activities related to

placement of borrow material on existing dune, supratidal, and intertidal habitats. The

proposed action would initially restore a total of 5,840 acres on Raccoon, Whiskey,

Trinity, and Timbalier Islands. This would include initial restoration of a total of 472

acres of dune, 4,320 acres of supratidal and 1,048 acres of intertidal habitat. Of the 5,840

acres restored, 3,283 acres would be created and 2,557 acres of existing beach, dune, or

intertidal habitats would be nourished with dredged material.


16

2.3.3 Effect on Mud Flats

A portion of the 1,315 acres of intertidal habitat that will exist at the beginning of project

construction are mud flats and will be covered with dredged material. These mud flats

will be planted with marsh vegetation and will provide 1,550 acres of intertidal habitat by

TY5.

2.3.4 Effect on Vegetated Shallows

A portion of the 1,315 acres of intertidal habitat that will exist at the beginning of project

construction is shallow backbarrier marsh habitat and will be covered with dredged

material. These areas will be planted with marsh vegetation and will provide 1,550 acres

of intertidal habitat by TY5.

2.3.5 Effect on Coral Reefs

Not applicable to this project.

2.4 Human Use Characteristics

2.4.1 Effect on Municipal and Private Water Supplies

No municipal or private water supplies exist within the project area.

2.4.2 Effect on Recreational and Commercial Fisheries

Direct impacts to fisheries resources of implementing the NER Plan would be localized

and short-term adverse impacts due to construction activities of the terminal groin at

Raccoon Island, dredging activities at borrow sites and access canals, as well as

placement of borrow for barrier island restoration.

2.4.3 Effect on Water-related Recreation

The immediate direct recreational resources impact from implementation of the NER

Plan would be temporary closure of each island’s Study Area during construction. In

addition, there will be a temporary decrease in the quality of recreational opportunities as

the wetland restoration sites are allowed to settle, vegetation is restored, and tidal

circulation is reestablished naturally. The recreational benefits and opportunities will

rebound as the restored marshes become established. As formulated, the plan involves

filling several canals on both Trinity and Timbalier Islands. These canals were excavated

and have been maintained to provide access to oil or gas wells and for houseboat

mooring. The filling of these canals will have a negative impact on that form of

recreation.

2.4.4 Aesthetic Effects

Aesthetics of the barrier island habitat and aquatic ecosystems apply to the perception of

beauty and quality of life enjoyed by the general public and property owners. It is

expected that all project components will be in keeping with general characteristics of the

area that will likely enhance areas of the aquatic ecosystem.


17

2.4.5 Effect on Parks, National and Historical Monuments, National

Seashores, Wilderness Areas, Research Sites, and Similar Preserves

Whiskey Island and Raccoon Island are part of the Terrebonne Barrier Island Refuge

(TBIR) which is managed by the Louisiana Department of Wildlife and Fisheries. The

purpose, along with objectives and goals of this project, is to improve degrading barrier

island conditions which will have a long-term positive effect on the TBIR.

3.0 Findings of Compliance or Non Compliance with the

Restrictions on Discharge

1) No significant adaptations of the guidelines were made relative to this evaluation.

2) No practicable alternative exists which meets the study objectives that does not

involve discharge of fill into waters of the United States.

3) The discharges of fill materials will not cause or contribute to, after consideration

of disposal site dilution and dispersion, violation of any applicable State water

quality standards for waters. The discharge operations will not violate the Toxic

Effluent Standards of Section 307 of the Clean Water Act.

4) The placement of fill materials in the Project A will not jeopardize the continued

existence of any species listed as threatened or endangered or result in the

likelihood of destruction or adverse modification of any critical habitat as

specified by the Endangered Species Act of 1973. Deposition of fill material in

the gulfside intertidal areas will adversely impact piping plover foraging areas. In

order to minimize impacts to this species, the sequencing of island construction

will allow these birds to temporarily relocate to suitable habitat within the

boundary of the Study.

5) The placement of fill materials will not result in significant adverse effects on

human health and welfare, including municipal and private water supplies,

recreational and commercial fishing, fish, shellfish, wildlife, and special aquatic

sites. The life stages of aquatic species and other wildlife will not be adversely

affected. Significant adverse effects on aquatic ecosystem diversity, productivity

and stability, and recreational, aesthetic, and economic values will not occur.



ENG FORM 4345, SEPT 2009 EDITION OF OCT 2004 IS OBSOLETE Proponent: CECW-OR

APPLICATION FOR DEPARTMENT OF THE ARMY PERMIT

(33 CFR 325)

OMB APPROVAL NO. 0710-0003

EXPIRES: 31 August 2012

Public reporting burden for this collection of information is estimated to average 11 hours per response, including the time for reviewing instructions, searching existing data

sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other

aspect of this collection of information, including suggestions for reducing this burden, to Department of Defense, Washington Headquarters, Executive Services and

Communications Directorate, Information Management Division and to the Office of Management and Budget, Paperwork Reduction Project (0710-0003). Respondents

should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not

display a currently valid OMB control number. Please DO NOT RETURN your form to either of those addresses. Completed applications must be submitted to the District Engineer

having jurisdiction over the location of the proposed activity.

PRIVACY ACT STATEMENT

Authorities: Rivers and Harbors Act, Section 10, 33 USC 403; Clean Water Act, Section 404, 33 USC 1344; Marine Protection, Research, and Sanctuaries Act, Section

103, 33 USC 1413; Regulatory Programs of the Corps of Engineers; Final Rule 33 CFR 320-332. Principal Purpose: Information provided on this form will be used in evaluating

the application for a permit. Routine Uses: This Information may be shared with the Department of Justice and other federal, state, and local government agencies, and the

public and may be made available as part of a public notice as required by Federal law. Submission of requested information is voluntary, however, if information is not

provided the permit application cannot be evaluated nor can a permit be issued. One set of original drawings or good reproducible copies which show the location and character

of the proposed activity must be attached to this application (see sample drawings and instructions) and be submitted to the District Engineer having jurisdiction over the

location of the proposed activity. An application that is not completed in full will be returned.

(ITEMS 1 THRU 4 TO BE FILLED BY THE CORPS)

1. APPLICATION NO. 2. FIELD OFFICE CODE 3. DATE RECEIVED 4. DATE APPLICATION COMPLETE

(ITEMS BELOW TO BE FILLED BY APPLICANT)

5. APPLICANTS NAME:

First  Middle - Last

Company  U.S. Army Corps of Engineers, New Orleans District

E-mail Address  William.P.Klein.Jr@usace.army.mil

8. AUTHORIZED AGENTS NAME AND TITLE (an agent is not required)

First  Middle - Last

Company  NA

E-mail Address - NA

6. APPLICANTS ADDRESS:

City  New Orleans State  Louisiana Zip 70160-0267 Country  USA

9. AGENTS ADDRESS

City  NA State  NA Zip  NA Country  NA

7. APPLICANTS PHONE NOs. W/AREA CODE.

a. Residence - NA b. Business - (504)862-2540 c. Fax- NA

10. AGENTS PHONE NOs. W/AREA CODE

a. Residence - NA b. Business - NA c. Fax - NA

STATEMENT OF AUTHORIZATION

11. I hereby authorize, ___________to act in my behalf as my agent in the processing of this application and to furnish, upon request,

supplemental information in support of this permit application.

________________________________________________________________________________________________________________________________________________

APPLICANTS SIGNATURE D ATE

NAME, LOCATION, AND DESCRIPTION OF PROJECT OR ACTIVITY

12. PROJECT NAME OR TITLE (see instructions)

Louisiana Coastal Area  Terrebonne Basin Barrier Shoreline Restoration Project

13. NAME OF WATERBODY, IF KNOWN (if applicable),

Gulf of Mexico 14. PROJECT STREET ADDRESS (if applicable)

Address - NA

City - NA State  NA Zip - NA

15. LOCATION OF PROJECT:

Raccoon Whiskey Trinity Timbalier

Latitude N 29.0536 29.0460 29.0525 29.0753

Longitude W 90.9305 90.8312 90.7311 90.4962


ENG FORM 4345, SEPT 2009 EDITION OF OCT 2004 IS OBSOLETE Proponent: CECW-OR

16. OTHER LOCATION DESCRIPTIONS, IF KNOWN (see instructions)

The Project, located in LCA Subprovince 3, provides for the restoration of the Timbalier and Isles Dernieres barrier island chains located in Terrebonne Parish and Lafourche Parish,

Louisiana. The Isles Dernieres Reach represents a barrier island arc approximately 22 miles long in Terrebonne Parish that extends from Caillou Bay east to Cat Island Pass. Raccoon

Island, Whiskey Island, Trinity Island, East Island, and Wine Island (the primary islands that comprise the Isles Dernieres barrier island chain) are backed by Bay Blanc, Bay Round,

Caillou Bay, and Terrebonne Bay, and bordered by the Gulf of Mexico on the seaward side (Attachment 1). The Timbalier Reach is comprised of Timbalier Island and East Timbalier

Island. The two islands are on the western edge of the Lafourche barrier shoreline and are located about 60 miles southwest of New Orleans, Louisiana (Attachment 1). This barrier

island shoreline is approximately 20 miles long and backed by Terrebonne and Timbalier Bay to the north and delimited by Raccoon Pass to the east and Cat Island Pass to the west.

17. DIRECTIONS TO THE SITE:

Please see Section 16.


18. Nature of Activity (Description of project, include all features)

The project includes the restoration of Raccoon Island to its minimal geomorphologic form and ecologic function along with twenty-five (25) years of background erosion / land loss and

construction of a terminal groin. This plan also includes restoration of Whiskey and Trinity Islands to their minimal geomorphologic form and ecologic function along with five (5) years of

background erosion / land loss and restoration of Timbalier Island to its minimal geomorphologic form and ecologic function along with twenty-five (25) years of background erosion / land

loss. Immediately after construction, the project will add 3,283 acres of habitat (dune, intertidal, and supratidal) to the existing island footprints of Raccoon, Whiskey, Trinity, and Timbalier

Islands, increasing the total size of the islands to 5,840 acres. This includes approximately 472 acres of dune, 4,320 acres of supratidal habitat, and 1,048 acres of intertidal habitat. A

detailed description of the components for each island and the related construction activities is provided in Attachment 2. These components are summarized in the following table:

Table 1: Project Components*

Island

Proposed

Dune

Height

Proposed

Marsh

Height

Proposed

Dune

Crown

Width

Proposed

Dune

Slope

Proposed

Beach

Slope

Existing

Island

Footprint

Proposed

Island

Footprint

Net Increase

in Island

Footprint

Proposed Fill

Quantity:

Beach/Dune

Proposed Fill

Quantity:

Marsh

Proposed

Length of

Sand

Fencing

Used

(ft NAVD88) (ft NAVD88 (ft) (H:V) (H:V) (acres) (acres) (acres) (mcy) (mcy) (ft)

Raccoon +7.7 +3.7 100 30:1 60:1 235 789 554 5.2 5.1 11,912

Whiskey +6.4 +2.4 100 30:1 60:1 803 1,272 469 8.3 0.6 18,075

Trinity +6.4 +2.5 100 30:1 60:1 564 1,149 585 3.1 4.0 22,467

Timbalier +7.1 +3.2 100 30:1 60:1 955 2,630 1,675 10.7 9.1 35,425

*Please note that this information was developed for a feasibility level report and will be revised during Pre-construction, Engineering, and Design (PED).

Each of the islands in the project will require at least one renourishment event in order to maintain their geomorphologic form and ecologic function throughout the 50-year period of

analysis. Trinity Island will be renourished at TY25 (2037) while Raccoon and Timbalier will be renourished at TY30 (2042). Whiskey Island will require two renourishment events; one at

TY20 (2032) and one at TY40 (2052). Separate 404 permits will be submitted for the renourishment events.

Beach and Dune Construction

The contractor will use a hydraulic cutterhead dredge to excavate sand from the available sand borrow areas. The sand will then be pumped through a series of booster pumps to the

beach/dune fill template via a submerged sediment pipeline.

During construction the contractor will be directed to maintain dedicated equipment loading/unloading areas, staging areas, and access corridors to minimize the impacts to the island.

Existing mangrove habitats and prior restoration project areas shall be avoided by construction equipment and construction-related activities.

Once on the beach, the sediment pipeline will run parallel to the shoreline. Front-end loaders that are equipped with grapple arms will be utilized in the placement and relocation of the

sediment pipeline. For segments of the fill template that have sufficient width, a Y-valve will be utilized to enable placement of multiple sediment pipelines along the template. The

bifurcation of the discharge pipeline will facilitate lower discharge velocities and increased sediment retention within the fill template. In order to minimize the impact on piping plover (a

threatened and endangered species that inhabits the island), the beach will be constructed in sections to allow the birds to move to areas that are not currently under construction.

The sand will be worked on the beach by bulldozers to meet the specified template grades, slopes and widths. Construction methods may vary but it is anticipated that sand placement

along the shoreline will be controlled by advancing a temporary sand dike several hundred feet parallel to shore ahead of the discharge terminus. This aids in reducing initial fill losses

offshore and helps control temporary turbidity that may result from the fill placement operations. Typically water drainage and discharges will be directed offshore into the Gulf of Mexico

or into existing marsh areas to nourish these habitats.

If construction is completed during the summer, fall, or winter months, the dune and supratidal areas would be temporarily stabilized through aerial dispersion of grass seed. During the

first spring following construction, the dune and supratidal areas would be planted with a more permanent combination of plants. Vegetation would be manually planted on 8-foot centers

and would provide 100% coverage of the dune and supratidal areas. An additional 15% of the dune and supratidal swale areas will be planted with woody species in TY2 (2014). The

vegetation will be manually planted on 8-foot centers.

Back-Barrier Marsh Construction

As with the beach fill, it is anticipated that the contractor will use a hydraulic cutterhead dredge and booster pump(s) to excavate sediment from the available offshore marsh borrow

area(s) and directly transport it via a submerged sediment pipeline to the marsh platform. Sediment used to construct the marsh containment dikes will be dredged from existing material

inside the marsh creation area rather than from offshore borrow areas.

These operations will be done in a manner that will minimize turbidity. Discharge and dewatering from the marsh fill shall typically be directed towards the Gulf of Mexico including

orienting discharge pipes such that the hydraulic flow moves in a gulfward direction and locating dewatering structures on the gulf side of the Project area. The contractor may employ

other methods such as building interior containment dikes and creating a drainage gradient towards the gulf. If excess turbidity occurs, the contractor will be directed to change the

operating procedure to reduce the degree of turbidity.

Herbaceous planting of the marsh template will be conducted in two phases. The first phase will occur in the second year following construction (i.e. TY3 - 2015) and will consist of

covering 50% of the platform. The remaining 50% of the platform will be planted the following year. The vegetation will be manually planted on 8-foot centers.

19. Project Purpose (Describe the reason or purpose of the project, see Instructions)

Natural processes and human actions, such as the construction of oil field canals and the containment of waterways, have threatened the long-term viability of the project area. These

processes and activities have caused significant adverse impacts to the Terrebonne Basin barrier island shoreline, resulting in extensive barrier island habitat loss and ecosystem

degradation. The purpose of this project is to expand the footprints of four barrier islands (i.e. Raccoon, Whiskey, Trinity, and Timbalier Islands) to restore their geomorphic form and

ecologic function. This will effectively reduce land-loss rates within the project area to below historic land-loss rates (1880 through 2005). The project will also restore and improve

various barrier island habitats that provide essential habitats for fish, migratory birds, and other terrestrial and aquatic species, mimicking, as closely as possible, conditions which would

occur naturally in the area for the 50 year period of analysis. Furthermore, restoration of the four islands will increase sediment input to supplement long-shore sediment transport

processes along the gulf shoreline by mechanically introducing compatible sediment, and increasing the ability of the restored area to continue to function and provide habitat for the 50

year period of analysis with minimal continuing intervention.

USE BLOCKS 20-23 IF DREDGED AND/OR FILL MATERIAL IS TO BE DISCHARGED


20. Reason(s) for Discharge

The restoration of Raccoon, Whiskey, Trinity, and Timbalier Islands will require a considerable amount of fill material (e.g. marsh material for marsh creation and sand material for

beach/dune creation). This material will be dredged from a number of off-shore borrow areas located gulfward of the islands including Whiskey Island 3, New Cut, Raccoon, South Pelto,

and Ship Shoal (see Attachment 3). As previously stated, the contractor will use a hydraulic cutterhead dredge to excavate fill from the available borrow areas. The fill will then be pumped

through a series of booster pumps to the beach/dune fill template via a submerged sediment pipeline. If no action is taken, the barrier islands will continue to be subjected to the prevailing

erosional processes that will eventually result in a direct loss of the barrier islands to open water. This will reduce essential fish habitat, destroy critical habitat for threatened and

endangered species (i.e. the piping plover) and species of special interest (i.e. the brown pelican), impact fisheries resources, and diminish the storm-surge protection benefits of the barrier

island system.

21. Type(s) of Material Being Discharged and the Amount of Each Type in Cubic Yards:

The impacts of the Deepwater Horizon oil spill on the proposed borrow areas are uncertain at this time (August 2010). However, prior to any dredging activities, the borrow material will be

tested to insure that it is free of contaminants. Fill types and quantities for each of the fours islands are presented in the following sections and summarized in Table 2.

Raccoon

Fill quantities for the dune/beach and marsh components of Raccoon Plan E are 5.4 million and 4.6 million cubic yards, respectively. The plan will utilize beach/dune material from Ship

Shoal and marsh material from the Raccoon Island TE-48 borrow area. However, the borrow area does not have enough material to construct the marsh in its entirety. Therefore,

approximately 2.8 million cubic yards of sand will be dredged from Ship Shoal to provide a base layer for the marsh. The marsh material from the Raccoon Island TE-48 borrow area will

be deposited on the sand material to provide an adequate foundation for the marsh.

Whiskey

The plan will utilize beach/dune material from the Ship Shoal borrow area and marsh material from Whiskey 3a borrow area. Fill quantities for the initial construction of the dune/beach and

marsh components of Whiskey Plan C are 8.3 million and 0.6 million cubic yards, respectively.

Trinity

Trinity Plan C will utilize beach/dune material from Ship Shoal and marsh material from the Whiskey 3A borrow area. Fill quantities for the dune/beach and marsh components of Trinity

Plan C are 3.8 million and 3.8 million cubic yards, respectively.

Timbalier

Fill quantities for the dune/beach and marsh components of Timbalier Plan E are 10.7 million and 9.1 million cubic yards, respectively. Timbalier Plan E will utilize beach/dune material

from South Pelto and marsh material from Whiskey 3A (marsh material). However, the marsh borrow areas do not have adequate material to construct the marsh in its entirety. Therefore,

approximately 8.6 million cubic yards of sand will be dredged from South Pelto, Whiskey 3A (sandy material), and New Cut to provide a base layer for the marsh. The marsh material from

Whiskey 3A will be deposited on the sand material to provide an adequate foundation for the marsh.

Table 2: Fill Type and Quantities

Island Type of

Material

Fill Volume

(cy) Source

Source Fill

Volume

(cy)

Cut-to-Fill

Ratio

Cut Volume

(cy)

Depth of Cut

(ft)

Acreage

(acres)

Raccoon

Beach/Dune 5,381,956 Ship Shoal 5,381,956 1.13 6,081,610 12 315

Marsh 4,609,709 Ship Shoal 2,763,555 1.13 3,122,817 12 162

Raccoon 1,846,154 1.3 2,400,000 18 83

Whiskey Beach/Dune 8,330,215 Ship Shoal 8,330,215 1.13 9,413,143 12 487

Marsh 579,724 Whiskey 3A (marsh) 579,724 1.6 927,558 12 48

Trinity Beach/Dune 3,813,885 Ship Shoal 3,813,885 1.13 4,309,690 12 223

Marsh 3,772,925 Whiskey 3A (marsh) 3,772,925 1.6 6,036,680 12 312

Timbalier

Beach/Dune 10,702,818 South Pelto 10,702,818 1.13 12,094,184 13 577

Marsh 9,073,317

South Pelto 3,083,736 1.13 3,484,622 13 167

Whiskey 3A (beach) 3,630,769 1.3 4,720,000 8 366

Whiskey 3A (marsh) 435,735 1.6 697,176 12 37

New Cut 1,923,077 1.3 2,500,000 18 87


22. Surface Area in Acres of Wetlands or Other Waters Filled (see instructions) Acres Or Liner Feet

There are existing pockets of back-barrier marsh on each of the islands that will be covered with fill material during construction. Although construction of the project will result in temporary

impacts to these marshes, the creation of larger back-barrier marshes is expected to offset these impacts in the long term. Table 3 summarizes the anticipated area of marsh that will be

covered and the amount of new marsh created.

One of the primary objectives of the project is to increase the island footprints. This will require the placement of fill material in the Gulf of Mexico. Table 3 identifies the acreage of island

fill that will be placed in the open water adjacent to the existing island footprints.

Table 3: Fill Type and Quantities

Island

Area of Marsh

Covered at TY1

(acres)

Area of Marsh

Created at TY1

(acres)

Net Marsh

Created at TY1

(acres)*

Area of Open

Water Filled at TY1

(acres)**

Raccoon 5 318 313 554

Whiskey 105 110 5 469

Trinity 343 521 178 585

Timbalier 791 1063 272 1675

Total 1244 2012 768 3283

*Net Marsh Created equals the area of marsh created at TY1 minus the area of marsh covered at TY1

**Represents the acreage of the Gulf of Mexico that will be filled during construction

23. Description of Avoidance, Minimization, and Compensation (see instructions)

During the plan formulation, the proposed island plans for Raccoon and Whiskey Islands were shifted gulfward to avoid approximately 58 and 286 acres of existing mangroves on the

islands, respectively. This was done in order to minimize the ecologic impact during construction. Since these two islands are considered to be valuable wildlife habitats (Isles Dernieres

Barrier Islands Wildlife Refuge) and the LDWF is reestablishing a pelican rookery on Whiskey Island, maintaining adequate areas of healthy beach, dune, and marsh is particularly

important.

The project was also designed to avoid existing restoration projects on the islands. For example, Whiskey Plan C was designed to complement TE-50, which is an existing CWPPRA

project that was constructed in 2009. TE-50 created approximately 316 acres of intertidal back-barrier marsh between the two existing mangrove stands. Restoration of the beach and

dune gulfward of TE-50 will help to protect the existing CWPPRA investment.

Raccoon Plan E was designed to complement two separate CWPPRA projects, TE-29 and TE-48. The TE-29 project, which was completed in July 1997, included the construction of eight

segmented breakwaters along the eastern end of the island. The TE-48 project consists of two phases. Phase A, which included the construction of eight additional segmented

breakwaters and a terminal groin, was completed in September of 2005. The terminal groin, which was constructed on the eastern end of the island, was intended to prevent longshore

currents from scouring accumulated sediment behind the breakwater field. Phase B, which is currently in the pre-construction phase, will include the construction of a 53-acre marsh along

the backside of the island. The resilience of Raccoon Island Plan E is partially due to the existing breakwaters from both CWPPRA projects. The plan will help protected the marsh that will

be constructed as part of TE-48.

The mangrove stands and CWPPRA projects on Raccoon and Whiskey Island can be avoided without undermining the project because they are the only areas of sufficient elevation to

complement the design template and to contribute to the geomorphologic form and ecologic function of the islands. Avoidance of other pockets of existing habitat could potentially

undermine the project by providing weak spots in the template. These areas could be more susceptible to breaching and could accelerate erosion. Therefore, the remaining habitat on

Raccoon and Whiskey Island will be covered with fill material during construction of the template (i.e. at TY1). Existing habitat on Trinity and Timbalier Islands can not be avoided without

undermining the project. Therefore, the entire footprints of the islands will be covered with fill material, but will be restored through the vegetative planting efforts immediately following

construction.

No compensatory mitigation is required for this project. As an ecosystem restoration project, the alternatives were designed to avoid environmental impacts. Any incidental temporary

impacts that might be incurred during construction will be more than offset by the net habitat value created by the project.

24. Is Any Portion of the Work Already Complete? Yes ___ No __X_ IF YES, DESCRIBE THE COMPLETED WORK

25. Addresses of Adjoining Property Owners, Lessees, Etc., Whose Property Adjoins the Waterbody (If more than can be entered here, please attach a supplemental list).

The four islands in the project area are completed sounded by the Gulf of Mexico. The following sections describe the landownership of the actual islands.

Raccoon Island

Raccoon Island is owned by the State of Louisiana and is under the jurisdiction of the Louisiana Department of Wildlife & Fisheries for Isles Dernieres Barrier Island Refuge, therefore,

easements are not needed for this island, only a Grant of Particular Use.

Whiskey Island

Whiskey Island is owned by the State of Louisiana and is under the jurisdiction of the Louisiana Department of Wildlife & Fisheries for Isles Dernieres Barrier Island Refuge; therefore,

easements are not needed for this island, only a Grant of Particular Use.

Trinity Island

The majority of the island is owned by the State of Louisiana, however, a small portion of the island, approximately 30 acres, is privately owned by what appears to be one landowner. This

property owner will be identified during PED. A Standard Perpetual Beach Nourishment Easement would be acquired over these 30 acres of private property.

Timbalier Island

The majority of the island is owned by the State of Louisiana, however, one end of the island has some private ownership which is estimated to be approximately 80 acres. The ownership

of this land is heavily disputed; however, preliminary data indicates that each of the 11 estimated tracts contain multiple owners. These property owners will be identified during PED. A

Standard Perpetual Beach Nourishment Easement would be acquired over these 80 acres of private property.


26. List of Other Certifications or Approvals/Denials Received from other Federal, State, or Local Agencies for Work Described in This Application.

AGENCY TYPE APPROVAL* IDENTIFICATION NUMBER DATE APPLIED DATE APPROVED DATE DENIED

LDEQ Water Quality Certification TBD TBD

*Would include but is not restricted to zoning, building, and flood plain permits

27. Application is hereby made for a permit or permits to authorize the work described in this application. I certify that the information in this application is complete and

accurate. I further certify that I possess the authority to undertake the work described herein or am acting as the duly authorized agent of the applicant.

___________________________________ ____________ _______________________________ _______________

SIGNATURE OF APPLICANT DATE SIGNATURE OF AGENT DATE

The application must be signed by the person who desires to undertake the proposed activity (applicant) or it may be signed by a duly authorized agent if the statement in block 11 has been filled out and signed.

18 U.S.C. Section 1001 provides that: Whoever, in any manner within the jurisdiction of any department or agency of the United States knowingly and willfully falsifies, conceals, or covers up any

trick, scheme, or disguises a material fact or makes any false, fictitious or fraudulent statements or representations or makes or uses any false writing or document knowing same to

contain any false, fictitious or fraudulent statements or entry, shall be fined not more than $10,000 or imprisoned not more than five years or both.

ENG FORM 4345, SEPT 2009




APPENDIX E

LOUISIANA COASTAL RESOURCES

PROGRAM CONSISTENCY DETERMINATION



Volume V

APPENDIX E:

Louisiana Coastal Resources Program Consistency Determination

CONSISTENCY DETERMINATION

LOUISIANA COASTAL ZONE MANAGEMENT PROGRAM

LCA Terrebonne Basin Barrier Shoreline Restoration

Terrebonne and Lafourche Parish, Louisiana

INTRODUCTION

Section 307 of the Coastal Zone Management Act of 1972, 16 U.S.C. 1451 et. seq. requires that

"each federal agency conducting or supporting activities directly affecting the coastal zone shall

conduct or support those activities in a manner which is, to the maximum extent practicable,

consistent with approved state management programs." In accordance with Section 307, a

Consistency Determination has been prepared for the proposed LCA Terrebonne Basin Barrier

Shoreline Restoration, located in Terrebonne and Lafourche Parish, Louisiana. Coastal Use

Guidelines were written in order to implement the policies and goals of the Louisiana Coastal

Resources Program, and serve as a set of performance standards for evaluating projects.

Compliance with the Louisiana Coastal Resources Program, and therefore, Section 307, requires

compliance with applicable Coastal Use Guidelines.

PROJECT DESCRIPTION

The main objective and goal for this project, LCA Terrebonne Basin Barrier Shoreline

Restoration, is to restore the geomorphological form and ecological function of the Isles

Dernieres and Timbalier Barrier Islands. Specific objectives of this project are to:

• Restore the minimized barrier island conditions that provide the geomorphic form and

ecologic function of the Terrebonne Basin barrier island, reducing volume loss within

the TBBSR project area below the historic average (1880 through 2005).

• Restore and improve various barrier island habitats that provide essential habitats for

fish, migratory birds, and other terrestrial and aquatic species, mimicking, as closely

as possible, conditions which occur naturally in the area for the 50 year period of

analysis.

• Increase sediment input to supplement long-shore sediment transport processes along

the gulf shoreline by mechanically introducing compatible sediment, and increasing

the ability of the restored area to continue to function and provide habitat for the 50

year period of analysis with minimum continuing intervention.

The natural processes of subsidence and erosion have combined with human-caused effects

leading to significant shoreline retreat and land loss along the Terrebonne Basin barrier island

chain. Construction of levees along the Mississippi River to prevent flooding has effectively


stopped the nourishment of the wetlands with riverine nutrients and sediments. Confinement of

the Mississippi has also caused its bedload to be deposited in progressively deeper waters of the

GOM. In addition, the sediment load of the river has declined by over 50% due to flood control

works and bank stabilization upstream. The latter two factors have prevented the Mississippi

River sediments from nourishing the barrier islands (USACE, 2004a).

The Isles Dernieres and Timbalier Island Ranges consist of Raccoon, Whiskey, Trinity, East,

Wine, Timbalier, and East Timbalier Islands (Figure 1). These islands are expected to be

impacted by multiple tropical weather events over the next several decades. Each storm poses

the risk of breaching the existing islands. As a result, these barrier islands will continue to

degrade and migrate landward as an increasingly fragmented chain of smaller barrier islands.

The fragmentation of the barrier islands will progressively increase the risk of a single storm

event causing widespread fundamental changes in the hydrodynamics and ecological function of

the interior bay system. Based on historical trends, a direct hurricane or tropical storm impact

can be expected on a frequent basis.

Without action, this critical geomorphic feature that isolates the Terrebonne Basin estuaries from

the Gulf of Mexico will continue to degrade, existing breaches will widen and new breaches will

form, and portions of the project area will disappear in the near term. For example, Raccoon,

Whiskey, Trinity, East, and Wine Island are expected to completely disappear by 2052 if no

action is taken. By 2062, Timbalier and East Timbalier will only have six acres of subaerial

habitat left.

NER Plan

The NER Plan includes the restoration of Raccoon Island to its minimal geomorphologic form

and ecologic function along with twenty-five (25) years of advanced fill (Plan E) and

construction of a terminal groin. This plan also includes restoration of Whiskey and Trinity

Islands to their minimal geomorphologic form and ecologic function along with five (5) years of

advanced fill (Plan C) and restoration of Timbalier Island to its minimal geomorphologic form

and ecologic function along with twenty-five (25) years of advanced fill (Plan E). Approximately

5,840 acres would be restored for Alternative 5 (NER Plan).

The NER plan cannot be constructed under the current WRDA 2007 authorization. Therefore,

the Whiskey Island plan, a single-island increment of the NER, has been proposed as the first

component of construction. The USACE will seek additional authorization in order to construct

additional increments of the NER Plan. Therefore, this Coastal Zone Consistency Determination

pertains to the NER.

Whiskey Island Plan C

Immediately after construction (TY1), Whiskey Island Plan C will add 469 acres of habitat

(dune, intertidal, and supratidal) to the existing island footprint, increasing the size of the island

to 1,272 acres (Figure 2). Whiskey Plan C was designed to avoid approximately 286 acres of

existing mangroves on the island to minimize the ecologic impact during construction. Plan C

was also designed to complement TE-50, which is an existing CWPPRA project that was




constructed in 2009. TE-50 created approximately 316 acres of intertidal back-barrier marsh

between the two existing mangrove stands. The recommended component of construction will

utilize marsh material from the Whiskey 3a borrow area and beach/dune material from the Ship

Shoal borrow area (Figure 3).

Whiskey Plan C will require two renourishment intervals. The first will occur at TY20 and will

include the addition of the same amount of dune and supratidal beach habitat that was originally

created in TY1 (i.e. add a Plan C to the template at TY20). The second renourishment interval

will occur at TY40 and will include the addition of the same amount of dune and supratidal

beach habitat needed to construct a Plan B template. No additional marsh material will be added.

Figure 1. Project Area




Figure 2. Whiskey Island Plan C – First Component of Construction

Figure 3. Proposed Borrow Areas




Trinity Plan C

Immediately after construction (TY1), the Trinity Plan C will add 585 acres of habitat (dune,

intertidal, and supratidal) to the existing 564-acre island footprint, increasing the size of the

island to 1,149 acres. This includes 129 acres of dune, 456 acres of supratidal, and 564

acres of intertidal habitat.

Trinity Plan C will utilize beach/dune material from Ship Shoal and marsh material from the

Whiskey 3A borrow area. Fill quantities for the dune/beach and marsh components of Trinity

Plan C are 3.8 million and 3.8 mcy, respectively. For the dune area, the material will be pumped

from the dredge to the beach. The material will then be worked on the beach by bulldozers and

front-end loaders. For the marsh area, the material will be pumped from the offshore borrow

site. Containment dikes will be constructed around the perimeter. Sediment for the containment

dikes will be dredged from existing material inside the marsh creation area. These operations

will be completed in a manner that will minimize turbidity of the water at the dredge site and the

discharge site. Figure 4 presents the plan view of Trinity Plan C.

Approximately 22,500 ft of sand fencing will be installed to promote deposition of windblown

sand, create dune features, reduce trampling of existing dunes by beach visitors, and protect

vegetative plantings. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-ft centers.

Figure 4. Trinity Island Plan C.




Raccoon Island Plan E with Terminal Groin

Immediately after construction (TY1), the Raccoon Plan E will add 554 acres of habitat (dune,

intertidal, and supratidal) to the existing 235-acre island footprint, increasing the size of the

island to 789 acres. This includes 63 acres of dune, 688 acres of supratidal, and 38 acres of

intertidal habitat.

Eight detached and segmented breakwaters were constructed as part of a CWPPRA project (TE29) in 1997. The breakwaters were installed to reduce shoreline retreat, promote sediment

deposition along the beach, and to protect seabird habitat. Due to the success of the TE-29

breakwaters, eight additional breakwaters were constructed as part of a separate CWPPRA

project (TE-48) that was completed in 1997. The breakwaters were installed west of the original

breakwaters. TE-48 also included the creation of approximately 60 acres of emergent and

intertidal back-barrier marsh.

Raccoon Plan E was designed to complement the intertidal marsh created as part of TE-48. Plan

E was also designed to avoid approximately 58 acres of existing mangroves immediately

adjacent to and gulfward of TE-48 (Figure 5).

A terminal groin will also be constructed as part of Raccoon Island Plan E. The terminal groin

will be approximately 1200 ft long and 75 ft wide and will be installed at the western terminus of

the template to prevent sediment migration out of the Isle Dernieres system.

Fill quantities for the dune/beach and marsh components of Raccoon Plan E are 5.4 million and

4.6 mcy, respectively. The plan will utilize beach/dune material from Ship Shoal and marsh

material from the Raccoon Island TE-48 borrow area. However, the borrow area does not have

enough material to construct the marsh in its entirety. Therefore, approximately 2.8 mcy of sand

will be dredged from Ship Shoal to provide a base layer for the marsh. The marsh material from

the Raccoon Island TE-48 borrow area will be deposited on the sand material to provide an

adequate foundation for the marsh.

For the dune area, the material will be pumped from the dredge to the beach. The material will

then be worked on the beach by bulldozers and front-end loaders. For the marsh area, the

material will be pumped from the offshore borrow site. Containment dikes will be constructed

around the perimeter. Sediment for the containment dikes will be dredged from existing material

inside the marsh creation area. These operations will be completed in a manner that will

minimize turbidity of the water at the dredge site and the discharge site. Figure 5 presents the

plan view of Raccoon Plan E and the proposed terminal groin.

Approximately 12,200 ft of sand fencing will be installed to promote deposition of windblown

sand, create dune features, reduce trampling of existing dunes by beach visitors, and protect




vegetative plantings. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-ft centers.

Figure 5. Raccoon Island Plan E with Terminal Groin.

Timbalier Island Plan E

Timbalier Plan E proposes a dune height of +7.1 ft NAVD 88 with a dune crown width of 100 ft.

The slopes of the beach and dune are set 60:1 and 30:1 (horizontal to vertical), respectively. The

marsh fill is proposed on the landward side of the dune at an elevation of +3.2 ft NAVD 88. As

with Raccoon Island Plan E, the elevations of the plan are larger than that of Trinity and

Whiskey because it is designed to withstand a longer period of background erosion.

Furthermore, the larger plans are thicker and thus exhibit higher compaction rates.

Immediately after construction (TY1), the Timbalier Plan E will add 1675 acres of habitat (dune,

intertidal, and supratidal) to the existing 955-acre island footprint, increasing the size of the

island to 2,630 acres. This includes 215 acres of dune, 2346 acres of supratidal, and 69 acres of

intertidal habitat.

Fill quantities for the dune/beach and marsh components of Timbalier Plan E are 10.7 million

and 9.1 mcy, respectively. Timbalier Plan E will utilize beach/dune material from South Pelto

and marsh material from Whiskey 3A (marsh material). However, the marsh borrow areas do

not have adequate material to construct the marsh in its entirety. Therefore, approximately 8.6

mcy of sand will be dredged from South Pelto, Whiskey 3A (sandy material), and New Cut to


	

provide a base layer for the marsh. The marsh material from Whiskey 3A will be deposited on

the sand material to provide an adequate foundation for the marsh.

For the dune area, the material will be pumped from the dredge to the beach. The material will

then be worked on the beach by bulldozers and front-end loaders. For the marsh area, the

material will be pumped from the offshore borrow site. Containment dikes will be constructed

around the perimeter. Sediment for the containment dikes will be dredged from existing material

inside the marsh creation area. These operations will be completed in a manner that will

minimize turbidity of the water at the dredge site and the discharge site. Figure 6 presents the

plan view of Timbalier Plan E.

Approximately 35,500 ft of sand fencing will be installed to promote deposition of windblown

sand, create dune features, reduce trampling of existing dunes by beach visitors, and protect

vegetative plantings. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-ft centers.

Figure 6. Timbalier Plan E.





GUIDELINES

1. Guidelines Applicable to All Uses

Guideline 1.1: The guidelines must be read in their entirety. Any proposed use may be subject to

the requirements of more than one guideline or section of guidelines and all applicable guidelines

must be complied with.

Response: Acknowledged.

Guideline 1.2: Conformance with applicable water and air quality laws, standards, and

regulations, and with those other laws, standards and regulations which have been incorporated

into the coastal resources program shall be deemed in conformance with the program except to

the extent that these guidelines would impose additional requirements.

Response: Acknowledged.

Guideline 1.3: The guidelines include both general provisions applicable to all uses and specific

provisions applicable only to certain types of uses. The general guidelines apply in all situations.

The specific guidelines apply only to situations they address. Specific and general guidelines

should be interpreted to be consistent with each other. In the event there is an inconsistency, the

specific should prevail.

Response: Acknowledged.

Guideline 1.4: These guidelines are not intended to, nor shall they be, interpreted so as to result

in an involuntary acquisition or taking of property.

Response: Acknowledged.

Guideline 1.5: No use or activity shall be carried out or conducted in such a manner as to

constitute a violation of the terms of a grant or donation of any lands or water bottoms to the

State or any subdivision thereof. Revocations of such grants and donations shall be avoided.

Response: The NER Plan would not cause violations or revocations of such grants or

donations.

Guideline 1.6: Information regarding the following general factors shall be utilized by the

permitting authority in evaluating whether the proposed use is in compliance with the guidelines.

a) type, nature, and location of use.

b) elevation, soil, and water conditions and flood and storm hazard characteristics of site.

c) techniques and materials used in construction, operation, and maintenance of use.

d) existing drainage patterns and water regimes of surrounding area including flow,

circulation, quality, quantity, and salinity; and impacts on them.

e) availability of feasible alternative sites or methods for implementing the use.




f) designation of the area for certain uses as part of a local program.

g) economic need for use and extent of impacts of use on economy of locality.

h) extent of resulting public and private benefits.

i) extent of coastal water dependency of the use.

j) existence of necessary infrastructure to support the use and public costs resulting from the

use.

k) extent of impacts on existing and traditional uses of the area and on future uses for which

the area is suited.

l) proximity to and extent of impacts on important natural features such as beaches, barrier

islands, tidal passes, wildlife and aquatic habitats, and forest lands.

m) the extent to which regional, state, and national interests are served including the

national interest in resources and the siting of facilities in the coastal zones as identified in the

coastal resources program.

n) proximity to, and extent of, impacts on special areas, particular areas, or other areas of

particular concern of the state program or local programs.

o) likelihood of, and extent of impacts, resulting secondary impacts and cumulative

impacts.

p) proximity to, and extent of, impacts on public lands or works, or historic, recreational or

cultural resources.

q) extent of impacts on navigation, fishing, public access, and recreational opportunities.

r) extent of compatibility with natural and cultural setting.

s) extent of long-term benefits or adverse impacts.

Response: All of the above are acknowledged

Guideline 1.7: It is the policy of the coastal resources program to avoid the following adverse

impacts. To this end, all users and activities shall be planned, sited, designed, and constructed,

operated, and maintained to avoid to the maximum extent practicable significant:

a) reductions in the natural supply of sediment and nutrients to the coastal system by

alterations of freshwater flow.

Response: The proposed project will introduce sediments into the coastal system and will

not impact nutrient supply or freshwater flow.

b) adverse economic impacts on the locality of the use and affected governmental bodies.

Response: Long-term economic benefits to the region and nation are anticipated as a

result of project implementation. Improved habitat for fish and wildlife, reduction in

conversion of marsh to open water, reduction in storm surge, and improved recreational

benefits would result upon project completion.

c) detrimental discharges of inorganic nutrient compounds into coastal waters.

Response: There would be a temporary increase in the concentration of inorganic nutrient

compounds near the dredging/clearing and/or construction locations due to resuspension


of sediments during dredging operations. Any effects are expected to be minor and

would only occur during actual dredging and construction operations.

d) alterations in the natural concentration of oxygen in coastal waters.

Response: Biological oxygen demand (BOD) in the dredge plume in the borrow area(s)

or project area will likely be greater than surrounding water if the disturbed sediments

have a high organic content. The decrease in dissolved oxygen accompanying high BOD

could result in a localized hypoxic water column or bottom-water conditions. The

increased turbidity will be localized and the dredge plume is expected to impact water

quality in a surface area of 5-10 areas. Ambient oxygen concentrations would return once

dredging operations were completed.

e) destruction or adverse alterations of streams, wetland, tidal passes, inshore waters and

water bottoms, beaches, dunes, barrier islands, and other natural biologically valuable areas or

protective coastal features.

Response: The NER Plan will initially create (FWP-FWOP) 3,283 acres of barrier island

habitat, including 387 acres of dune, 3,168 acres of supratidal, and -271 acres of intertidal

habitat. By TY5, the project will net 323 acres of intertidal habitat as the elevation of the

supratidal habitat settles to within the intertidal zone. The net benefit of the project will

offset any adverse effects to streams, tidal passes, beaches, dunes, barrier islands, or

protective coastal features. The Impacts associated with dredging access and access

channels are unavoidable and would result in a brief variation in bottom topography.

f) adverse disruption of existing social patterns.

Response: The area is remote, accessible only by boat or aircraft, and uninhabited.

Adverse social impacts might occur temporarily from the rerouting of recreational boat

traffic near dredging operations. However, any disruptions would be short-term and are

not expected to disrupt existing social patterns.

g) alterations of the natural temperature regime of coastal waters.

Response: Project construction would not cause a measurable change in the natural

temperature regime of coastal waters, effecting only the Gulf of Mexico and Caillou

Boca. Temporary and localized increases in water temperatures might occur with

increased turbidity during dredging operations; however, temperatures would return to

ambient levels following completion of dredging operations.

h) detrimental changes in existing salinity regimes.

Response: No detrimental change in existing salinity regimes would occur.

i) detrimental changes in littoral and sediment transport processes.


Response: This plan would not adversely affect littoral or sediment transport processes.

Sediment will be added to the system thus increasing the sediment available for longshore

transport. The proposed terminal groin on Timbalier Island will trap a portion of the sediment

being transported west via longshore transport. This will reduce the loss of sediment from the

Terrebonne Barrier Shoreline system.

j) adverse effects of cumulative impacts.

Response: Adverse or cumulative impacts to the NER are described in Section 5 of the

Integrated Feasibility Study and Final Environmental Impact Statement.

k) detrimental discharges of suspended solids into coastal waters, including turbidity

resulting from dredging.

Response: This project will increase turbidity in the immediate area of dredging.

Turbidity is expected to return to ambient conditions once dredging is completed..

During sediment emplacement, suspended particulate matter in the receiving water may

increase in a limited area and would likely have minimal effects on water quality.

Drilling mud discharge from OCS operations, exhumed contaminants, or trash and debris

present in the dredged material could also become suspended during emplacement within

the fill area.

l) reductions or blockage of water flow or natural circulation patterns within or into an

estuarine system or wetland forest.

Response: Circulation patterns would not be altered for any estuarine systems.

m) discharges of pathogens or toxic substances into coastal waters.

Response: No pathogens would be discharged.

.

n) adverse alteration or destruction of archaeological, historical, or other cultural resources.

Response: Appropriate cultural resources clearance will be obtained prior to any dredging

or construction activities.

.

o) fostering of detrimental secondary impacts in undisturbed or biologically highly

productive wetland areas.

Response: No detrimental secondary impacts are expected in undisturbed or biologically

highly productive wetlands.

p) adverse alteration or destruction of unique or valuable habitats, critical habitat for

endangered species, important wildlife or fishery breeding or nursery areas, designated wildlife

management or sanctuary areas, or forest lands.




Response: The project will be constructed within the Isles Dernieres Barrier Islands

Refuge. Critical habitat for piping plover (Charadrius melodus), which includes intertidal

beaches, mudflats, sand flats, algal flats, and wash-over passes may be temporarily

impacted by the proposed project. The project area also includes nesting habitat for

species of special interest including the brown pelican and colonial nesting birds. The

Biological Assessment and Main Report contain a protection plan for these species. The

temporary impacts will be offset by the long-term net benefit provided by restoration of

the beach, dune, and backbarrier marsh habitats. There could be temporary displacement

of wildlife and aquatic organisms away from dredging and disposal sites due to turbidity

and physical disturbance by construction equipment; however, the project would

ultimately increase the quantity and quality of available habitats for terrestrial and aquatic

organisms to utilize.

q) adverse alteration or destruction of public parks, shoreline access points, public works,

designated recreation areas, scenic rivers, or other areas of public use and concern.

Response: No such areas would be adversely impacted.

r) adverse disruptions of coastal wildlife and fishery migratory patterns.

Response: No adverse disruptions of wildlife and fishery migratory patterns are

anticipated to occur. There could be temporary displacement of wildlife and

fishery organisms away from dredging and disposal sites due to turbidity and

physical disturbance by construction equipment. However, any such impacts

would be minimally disruptive since most fish and wildlife in the area are mobile

and would move to adjacent undisturbed areas during construction activities.

s) land loss, erosion, and subsidence.

Response: No land loss, erosion, or subsidence would result from the proposed project.

The effect from this project would be a net gain in wetland habitat.

t) increases in the potential for flood, hurricane, or other storm damage, or increases in the

likelihood that damage will occur from such hazards.

Response: The proposed project would not increase flooding potential.

u) reductions in the long-term biological productivity of the coastal ecosystem.

Response: The proposed project would not result in long-term reduction of biological

productivity; to the contrary, the project is intended to increase biological productivity.

Guideline 1.8: In those in which the modifier "maximum extent practicable" is used, the

proposed use is in compliance with the guideline if the standard modified by the term is




complied with. If the modified standard is not complied with, the use will be in compliance with

the guideline if the permitting authority finds, after a systematic consideration of all pertinent

information regarding the use, the site, and the impacts of the use as set forth in Guideline 1.6,

and a balancing of their relative significance, that the benefits resulting from the proposed use

would clearly outweigh the adverse impacts resulting from noncompliance with the modified

standard and there are no feasible and practical alternative locations, methods, and practices for

the use that are in compliance with the modified standard and:

a) significant public benefits will result from the use, or;

b) the use would serve important regional, state, or national interests, including the

national interest in resources and the sitting of facilities in the coastal zone identified in the

coastal resources program, or;

c) the use is coastal water dependent.

The systematic consideration process shall also result in a determination of those conditions

necessary for the use to be in compliance with the guideline. Those conditions shall assure that

the use is carried out utilizing those locations, methods, and practices which maximize

conformance to the modified standard; are technically, economically, environmentally, socially,

and legally feasible and practical and minimize or offset those adverse impacts listed in guideline

1.7 and in the guideline at issue.

Response: Acknowledged.

Guideline 1.9: Uses shall, to the maximum extent practicable, be designed and carried out to

permit multiple concurrent uses which are appropriate for the location and to avoid unnecessary

conflicts with other uses of the vicinity.

Response: The purpose of the proposed project is for improved habitat (fish and wildlife)

and recreational use. After construction, recreational pursuits would be encouraged to the

maximum extent practicable.

Guideline 1.10: These guidelines are not intended to be, nor shall they be, interpreted to allow

expansion of governmental authority beyond that established by La. R.S. 49:213.1 through

213.21, as amended; nor shall these guidelines be interpreted so as to require permits for specific

uses legally commenced or established prior to the effective date of the coastal use permit

program nor to normal maintenance or repair of such uses.

Response: Acknowledged.

2. Guidelines for Levees

Guideline 2.1: The leveeing of unmodified or biologically productive wetlands shall be avoided

to the maximum extent practicable.




Response: No permanent levees will be constructed that would disrupt biologically

productive wetlands. Dikes will be constructed to contain beach and marsh fill material.

These dikes will be constructed in a manner so that they will subside/degrade naturally so

as to minimize impacts to natural hydrology.

Guideline 2.2: Levees shall be planned and sited to avoid segmentation of wetland areas and

systems to the maximum extent practicable.

Response: See Guideline 2.1.

Guideline 2.3: Levees constructed for the purpose of developing or otherwise changing the use

of a wetland area shall be avoided to the maximum extent practicable.

Response: No levees associated with this project would encourage or cause development

or change the use of wetlands.

Guideline 2.4: Hurricane and flood protection levees shall be located at the wetland/non-wetland

interface or landward to the maximum extent practicable.

Response: The project does not include construction of hurricane or flood protection

levees.

Guideline 2.5: Impoundment levees shall only be constructed in wetland areas as part of

approved water or marsh management projects or to prevent release of pollutants.

Response: No permanent levees will be constructed that would disrupt biologically

productive wetlands. Dikes will be constructed to contain beach and marsh fill material.

These dikes will be constructed in a manner so that they will subside/degrade naturally so

as to minimize impacts to natural hydrology.

Guideline 2.6: Hurricane or flood protection levee systems shall be designed, built, and thereafter

operated and maintained utilizing best practical techniques to minimize disruptions of existing

hydrologic patterns, and the interchange of water, beneficial nutrients and aquatic organisms

between enclosed wetlands and those outside the levee system.

Response: The project area does not include construction of hurricane or flood protection

levees.

.

3. Guidelines for Linear Facilities

Guideline 3.1: Linear use alignments shall be planned to avoid adverse impacts on areas of high

biological productivity or irreplaceable resource areas.




Response: Acknowledged. Temporary dredge pipeline placement will be planned to

avoid areas of high biological productivity or irreplaceable resource areas.

.

Guideline 3.2: Linear facilities involving the use of dredging or filling shall be avoided in

wetland and estuarine areas to the maximum extent practicable.

Response: This project involves the restoration of a barrier island which includes,

subtidal, intertidal, and supratidal placement of dredged materials. Existing wetlands will

be avoided to the maximum extent practicable to maximize the net benefit of the project.

Guideline 3.3: Linear facilities involving dredging shall be of the minimum size and length.

Response: Acknowledged.

Guideline 3.4: To the maximum extent practicable, pipelines shall be installed through the "push

ditch" method and the ditch backfilled.

Response: Acknowledged.

Guideline 3.5: Existing corridors, right-of-way, canals, and streams shall be utilized to the

maximum extent practicable for linear facilities.

Response: Acknowledged.

Guideline 3.6: Linear facilities and alignments shall be, to the maximum extent practicable,

designed and constructed to permit multiple uses consistent with the nature of the facility.

Response: Temporary disruption to multiple uses of the project area may occur during

dredging operations, but would be restored following project completion.

Guideline 3.7: Linear facilities involving dredging shall not traverse or adversely affect any

barrier island.

Response: The proposed project involves the restoration of a barrier island. The benefit

will outweigh any unavoidable adverse impacts associated with project construction.

Guideline 3.8: Linear facilities involving dredging shall not traverse beaches, tidal passes,

protective reefs or other natural gulf shoreline unless no other alternative exists. If a beach, tidal

pass, reef or other natural gulf shoreline must be traversed for a non-navigation canal, they shall

be restored at least to their natural condition immediately upon completion of construction. Tidal

passes shall not be permanently widened or deepened except when necessary to conduct the use.

The best available restoration techniques which improve the traversed area's ability to serve as a

shoreline shall be used.

Response: Acknowledged. See response to Guideline 3.7.


Guideline 3.9: Linear facilities shall be planned, designed, located, and built using the best

practical techniques to minimize disruption of natural hydrologic and sediment transport

patterns, sheet flow, and water quality, and to minimize adverse impacts on wetlands.

Response: Acknowledged.

Guideline 3.10: Linear facilities shall be planned, designed, and built using the best practical

techniques to prevent bank slumping and erosion, saltwater intrusion, and to minimize the

potential for inland movement of storm-generated surges. Consideration shall be given to the use

of locks in navigation canals and channels which connect more saline areas with fresher areas.

Response: Acknowledged.

Guideline 3.11: All non-navigation channels, canals and ditches which connect more saline

areas with fresher areas shall be plugged at all waterway crossings and at intervals between

crossings in order to compartmentalize them. The plugs shall be properly maintained.

Response: Acknowledged.

Guideline 3.12: The multiple use of existing canals, directional drilling and other practical

techniques shall be utilized to the maximum extent practicable to minimize the number and size

of access canals, to minimize changes of natural systems and to minimize adverse impacts on

natural areas and wildlife and fisheries habitats.

Response: Acknowledged.

Guideline 3.13: All pipelines shall be constructed in accordance with parts 191, 192, and 195 of

Title 49 of the Code of Federal Regulations, as amended, and in conformance with the

Commissioner of Conservation’s Pipeline Safety Rules and Regulations and those safety

requirements established by LA R.S. 45:408, whichever would require higher standards.

Response: Acknowledged.

Guideline 3.14: Areas dredged for linear facilities shall be backfilled or otherwise restored to the

pre-existing conditions upon cessation of use for navigation purposes to the maximum extent

practicable.

Response: Acknowledged.

Guideline 3.15: The best practical techniques for site restoration and re-vegetation shall be

utilized for all linear facilities.

Response: Acknowledged.




Guideline 3.16: Confined and dead end canals shall be avoided to the maximum extent

practicable. Approved canals must be designed and constructed using the best practical

techniques to avoid water stagnation and eutrophication.

Response: The proposed project would not construct confined or dead end canals.

4. Guidelines for Dredged Spoil Deposition

Guideline 4.1: Spoil shall be deposited utilizing the best practical techniques to avoid disruption

of water movement, flow, circulation, and quality.

Response: Acknowledged. All dredged material will be deposited in a manner that is beneficial

to the restoration project.

Guideline 4.2: Spoil shall be used beneficially to the maximum extent practicable to improve

productivity or create new habitat, reduce or compensate for environmental damage done by

dredging activities, or prevent environmental damage. Otherwise, existing spoil disposal areas or

upland disposal shall be utilized to the maximum extent practicable rather than creating new

disposal areas.

Response: Acknowledged.

Guideline 4.3: Spoil shall not be disposed of in a manner which could result in the impounding

or draining of wetlands or the creation of development sites unless spoil deposition is part of an

approved levee or land surface alteration project.

Response: Dredged material will be used beneficially in the construction of the beach,

dune, or intertidal areas. Temporary dikes will be constructed to contain the dredged

material during the dewatering process. These dikes are anticipated to subside and

degrade over time thus preventing the formation of a permanent impoundment.

Guideline 4.4: Spoil shall not be disposed of on marsh, known oyster or clam reefs, or in areas of

submerged vegetation to the maximum extent practicable.

Response: This project was designed to avoid existing back barrier marsh/mangrove

habitat to the maximum extent practicable. Some emergent marsh will be covered with

fill material. However, the long term habitat benefits created by the project outweigh the

impacts associated with project construction. No dredged material will be placed on

known oyster or clam reefs.

Guideline 4.5: Spoil shall not be disposed of in such a manner as to create a hindrance to

navigation or fishing, or hinder timber growth.




Response: No hindrance to navigation, fishing, and timber growth would occur. The

project area may be unavailable for fishing activities during construction; however,

alternative fishing areas exist nearby and fishing access would be restored after

construction.

Guideline 4.6: Spoil disposal areas shall be designed and constructed and maintained using the

best practicable techniques to retain the spoil at the site, reduce turbidity, and reduce shoreline

erosion when appropriate.

Response: Acknowledged. The project involves placing hydraulically dredged material in

designated areas for barrier island construction. Every effort will be made to retain the

material on the site. Best management practices will be used to minimize turbidity

associated with dredging and runoff.

Guideline 4.7: The alienation of state-owned property shall not result from spoil deposition

activities without the consent of the Department of Natural Resources.

Response: No state-owned properties would be alienated by deposition of dredged

material.

5. Guidelines for Shoreline Modification

Guideline 5.1: Non structural methods of shoreline protection shall be utilized to the maximum

extent practicable.

Response: Acknowledged. The project is a non structural method of shoreline

restoration.

Guideline 5.2: Shoreline modification structures shall be designed and built using best practical

techniques to minimize adverse impacts.

Response: Acknowledged

Guideline 5.3: Shoreline modification structures shall be lighted or marked in accordance with

U.S. Coast Guard regulations, to not interfere with navigation, and they should foster fishing,

other recreational opportunities, and public access.

Response: Acknowledged.

Guideline 5.4: Shoreline modification structures shall be built using best practical techniques to

avoid the introduction of pollutants and toxic substances into coastal waters.

Response: Acknowledged.

Guideline 5.5: Piers and docks and other harbor structures shall be designed and built using best

practical techniques to avoid obstruction of water circulation.




Response: The proposed action would not construct any piers, docks or other harbor

structures.

Guideline 5.6: Marinas and similar commercial and recreational developments shall to the

maximum extent practicable not be located so as to result in adverse impacts on open productive

oyster beds, or submerged grass beds.

Response: The proposed action would not construct any marinas or similar commercial

or recreational developments.

Guideline 5.7: Neglected or abandoned shoreline modification structures, piers, docks, mooring

and other harbor structures shall be removed at the owner’s expense, when appropriate.

Response: Acknowledged.

Guideline 5.8: Shoreline stabilization structures shall not be built for the purpose of creating fill

areas for development unless part of an approved surface alteration use.

Response: Acknowledged.

Guideline 5.9: Jetties, groins, breakwaters and similar structures shall be planned, designed and

constructed so as to avoid to the maximum extent practicable downstream land loss and erosion.

Response: Acknowledged.

6. Guidelines for Surface Alterations

Guideline 6.1: Industrial, commercial, urban, residential, and recreational uses are necessary to

provide adequate economic growth and development. To this end, such uses will be encouraged

in those areas of the coastal zone that are suitable for development. Those uses shall be

consistent with the other guidelines and shall, to the maximum extent practicable, take place

only:

a) on lands five feet or more above sea level or within fast lands; or

b) on lands which have foundation conditions sufficiently stable to support the use, and

where flood and storm hazards are minimal or where protection from these hazards can be

reasonably well achieved, and where the public safety would not be unreasonably endangered;

and

1) the land is already in high intensity of development use, or

2) there is adequate supporting infrastructure, or

3) the vicinity has a tradition of use for similar habitation or development.

Response: Acknowledged.




Guideline 6.2: Public and private works projects such as levees, drainage improvements, roads,

airports, ports, and public utilities are necessary to protect and support needed development and

shall be encouraged. Such projects shall, to the maximum extent practicable, take place only

when:

a) they protect or serve those areas suitable for development pursuant to Guideline 6.1; and

b) they are consistent with other guidelines; and

c) they are consistent with all relevant adopted state, local, and regional plans.

Response: Acknowledged.

Guideline 6.3: Blank (Deleted by LA Department of Natural Resources).

Guideline 6.4: To the maximum extent practicable, wetland areas shall not be drained or filled.

Any approved drain or fill project shall be designed and constructed using best practical

techniques to minimize present and future property damage and adverse environmental impacts.

Response: This project was designed to avoid existing back barrier marsh/mangrove

habitat to the maximum extent practicable. Some emergent marsh will be covered with

fill material. However, the long term habitat benefits created by the project outweigh the

impacts associated with project construction.

Guideline 6.5: Coastal water-dependent uses shall be given special consideration in permitting

because of their reduced choice of alternatives.

Response: Acknowledged.

Guideline 6.6: Areas modified by surface alteration activities shall, to the maximum extent

practicable, be revegetated, refilled, cleaned, and restored to their pre-development condition

upon termination of the use.

Response: Acknowledged.

Guideline 6.7: Site clearing shall, to the maximum extent practicable, be limited to those areas

immediately required for physical development.

Response: Acknowledged.

Guideline 6.8: Surface alterations shall, to the maximum extent practicable, be located away

from critical wildlife areas and vegetation areas. Alterations in wildlife preserves and

management areas shall be conducted in strict accord with the requirements of the wildlife

management body.

Response: The restoration project is located on the Isles Dernieres Barrier Islands Refuge

which is managed by the LA Department of Wildlife and Fisheries. The proposed action




has been coordinated with LA Department of Wildlife and Fisheries, US Fish and

Wildlife, and National Marine Fisheries Service.

Guideline 6.9: Surface alterations which have high adverse impacts on natural functions shall not

occur, to the maximum extent practicable, on barrier islands and beaches, isolated cheniers,

isolated natural ridges or levees, or in wildlife and aquatic species breeding or spawning areas, or

in important migratory routes.

Response: The proposed action has been coordinated with the US Fish and Wildlife

Services and the National Marine Fisheries Service to minimize impacts to threatened

and endangered species and their critical habitat. The proposed action would involve

activities in the habitat of the piping plover, Kemp’s ridley and loggerhead sea turtles,

brown pelican, and colonial nesting waterbirds. The PDT is currently conducting a

Biological Assessment to assess potential direct and indirect impacts to the piping plover

and associated critical habitat and for the endangered and threatened sea turtles.

Furthermore, restrictions placed on activities to minimize disturbance to colonial nesting

birds will be observed.

Guideline 6.10: The creation of low dissolved oxygen conditions in the water or traps for heavy

metals shall be avoided to the maximum extent practicable.

Response: Low dissolved oxygen conditions may occur during dredging operations and

as a result of increased turbidity. However, any such construction-related conditions

would be of short duration and would return to ambient conditions after construction

activities were completed. Seasonal hypoxia occurs offshore of the barrier islands in the

vicinity of Ship Shoal and the other borrow areas. Borrow areas will be designed to

minimize the potential for creating or exacerbating the hypoxic conditions offshore.

Guideline 6.11: Surface mining and shell dredging shall be carried out utilizing the best practical

techniques to minimize adverse environmental impacts.

Response: Not applicable.

Guideline 6.12: The creation of underwater obstructions which adversely affect fishing or

navigation shall be avoided to the maximum extent practicable.

Response: No underwater obstructions would be created.

Guideline 6.13: Surface alteration sites and facilities shall be designed, constructed, and operated

using the best practical techniques to prevent the release of pollutants or toxic substances into the

environment and minimize other adverse impacts.

Response: Acknowledged.

Guideline 6.14: To the maximum extent practicable, only material that is free of contaminants

and compatible with the environmental setting shall be used as fill.




Response: The excavated material is expected to be free of contaminants, based on the

HTRW survey for the project area.

7. Guidelines for Hydrologic and Sediment Transport Modifications

Guideline 7.1: The controlled diversion of sediment laden waters to initiate new cycles of

wetland building and sediment nourishment shall be encouraged and utilized whenever such

diversion will enhance the viability and productivity of the outfall area. Such diversions shall

incorporate a plan for monitoring and reduction and/or amelioration of the effects of pollutants

present in the freshwater source.

Response: Not applicable.

Guideline 7.2: Sediment deposition systems may be used to offset land loss, to create or restore

wetland areas or enhance building characteristics of a development site. Such systems shall only

be utilized as part of an approved plan. Sediment from these systems shall only be discharged in

the area that the proposed use is to be accomplished.

Response: Not applicable.

Guideline 7.3: Undesirable deposition of sediments in sensitive habitat or navigation areas shall

be avoided through the use of the best preventive techniques.

Response: Acknowledged.

Guideline 7.4: The diversion of freshwater through siphons and controlled conduits and

channels, and overland flow to offset saltwater intrusion and to introduce sediment and nutrients

into wetlands shall be encouraged and utilized whenever such diversion will enhance the

viability and productivity of the outfall area. Such diversions shall incorporate a plan for

monitoring and reduction and/or amelioration of the effects of pollutants present in the

freshwater source.

Response: Not applicable.

Guideline 7.5: Water or swamp management plans shall result in an overall benefit to the

productivity of the area.

Response: Not applicable.

Guideline 7.6: Water control structures shall be assessed separately based on their individual

merits and impacts and in relation to their overall water or marsh management plan of which

they are a part.

Response: Not applicable.


	

Guideline 7.7: Weirs and similar water control structures shall be designed and built using the

best practical techniques to prevent “cut arounds,” permit tidal exchange in tidal areas, and

minimize obstruction to the migration of aquatic organisms.

Response: Acknowledged.

Guideline 7.8: Impoundments which prevent normal tidal exchange and/or the migration of

aquatic organisms shall not be constructed in brackish and saline areas to the maximum extent

practicable.

Response: Acknowledged.

Guideline 7.9: Withdrawal of surface and ground water shall not result in saltwater intrusion or

land subsidence to the maximum extent practicable.

Response: Not applicable.

8. Guidelines for the Disposal of Wastes

Response: The proposed action would not involve the disposal of wastes and, therefore,

these guidelines are not applicable.

9. Guidelines for Uses That Result in the Alteration of Waters Draining into Coastal

Waters

Response: The proposed action would not involve the alterations of waters draining into

coastal waters, and, therefore, these guidelines are not applicable.

10. Guidelines for Oil, Gas, and Other Mineral Activities

Response: The proposed action would not involve oil, gas, or other mineral activities,

and, therefore, these guidelines are not applicable.

CONSISTENCY DETERMINATION

Based on this evaluation, it is proposed that the NER Plan would be consistent, to the maximum

extent practicable, with the State of Louisiana's approved Coastal Resources Program.




APPENDIX F

PROGRAMMATIC AGREEMENT AMONG

USACE, CPRA, SHPO, AND ACHP































APPENDIX G

RESPONSES TO COMMENTS



Letter #1: Coalition to Restore Coastal Louisiana (CRCL)

SEIS August 2010


Letter #1: Coalition to Restore Coastal Louisiana (CRCL)

SEIS August 2010 CRCL1-01: The project delivery team evaluated a 7- island alternative. It was included in the final array and deemed not cost effective. The 4-island alternative was, however deemed cost effective and provides for a comprehensive system-wide restoration that addresses the near-term needs of the Terrebonne Barrier Islands. CRCL1-02: Alternative 10 restored all 7 islands to their minimum geomorphic form and ecological function, while alternative 5 included larger scales of island nourishment that would allow for an additional 5-25 years of background erosion. This overbuild provides more benefits than the minimum design and addresses the most critical islands in the system. CRCL1-03: There is a storm event built into the modeling every 20 years. During the period of years 11-20, this designed storm is anticipated to degrade the island at a faster rate than in years 0-10 as no storm is modeled in those years.


Letter #1: Coalition to Restore Coastal Louisiana (CRCL)

SEIS August 2010 CRCL1-04: Acknowledged. The State and USACE will be adaptively managing the project as outlined by the adaptive management plan. CRCL1-05: The project delivery team evaluated a number of measures including hardened structures. We do believe there is a benefit, in certain instances, for the use of hardened structures as evidenced by the recommendation of a terminal groin at the western end of Raccoon Island.


Letter #2: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS2-01: Acknowledged. The recommended measures will be implemented during construction.


Letter #2: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS2-02: The Biological Assessment contains a ‘likely to adversely affect’ determination for piping plover.


Letter #2: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS2-03: Acknowledged. The recommended measures will be implemented during construction.


Letter #2: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS2-04: Acknowledged. The recommended measures will be implemented during construction. USFWS2-05: Acknowledged. The recommended measures will be implemented during construction. USFWS2-06: Acknowledged. The recommended measures will be implemented during construction.


Letter #3: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010


Letter #3: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS3-01: Since we are requesting additional authorization for the NER plan (4-islands), the SEIS will highlight the benefits of both the 1-island TSP and the NER USFWS3-02: Acknowledged. Agencies will be provided an opportunity to review all reports. USFWS3-03: Acknowledged. Formal consultation will begin once the Biological Assessment is updated to include the NER plan along with the TSP. USFWS3-04: Acknowledged. Recommended measures will be implemented during construction.


Letter #3: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS3-05: Acknowledged. Recommended measures will be implemented during construction. USFWS3-06: Acknowledged. USFWS3-07: Monitoring and adaptive management specifics can be found in the Appendix. USFWS3-08: Acknowledged. Recommended measures will be implemented during construction. USFWS3-09: The Wine Island “Rock Ring” was evaluated and deemed not cost effective. USFWS3-10: The State and USACE are requesting additional authorization to construct the NER plan (alternative 5). USFWS3-11: Acknowledged. USFWS3-12: Alternatives 11 and 12 are increments of the NER Plan and were added to the final array. A descriptive write-up and Tables for each island plan are also included. See Table 3-35 and Table 3- 36.


Letter #3: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS3-13: See response #12. USFWS3-14: See response #12. USFWS3-15: Will update to include most recent information. USFWS3-16: Will revise for consistency. USFWS3-17: Acknowledged. Will include requested information. USFWS3-18: Acknowledged. Current version clarifies negative values. USFWS3-19: Typo noted. USFWS3-20: Acknowledged. This section has been revised to include a more thorough analysis of the NER. USFWS3-21: Acknowledged. Will revise species list accordingly. USFWS3-22: Acknowledged. A more thorough description of anticipated impacts to listed species will be provided.


Letter #3: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS3-24: Acknowledged. USFWS3-25: The Biological Assessment has been revised to include a ‘likely to adversely affect” determination for piping plover.


Letter #3: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010


Letter #4: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010


Letter #4: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS4-01: The Biological Assessment has been revised to include a ‘likely to affect” determination for piping plover and includes affects of both the TSP and NER. USFWS4-02: Acknowledged. Report has been revised. USFWS4-03: Acknowledged. Report has been revised. USFWS4-04: Acknowledged. Report has been revised.


Letter #4: U.S. Fish and Wildlife Service (USFWS)

SEIS August 2010 USFWS4-05: Acknowledged. Report has been revised. USFWS4-06: Acknowledged. Report has been revised.


Letter #5: U.S. Environmental Protection Agency (USEPA)

SEIS August 2010


Letter #5: U.S. Environmental Protection Agency (USEPA)

SEIS August 2010 USEPA5-01: The impacts of the Deepwater Horizon oil spill on coastal Louisiana are uncertain at this time (May 11, 2010). This spill could potentially adversely impact USACE water resources projects and studies within the Louisiana coastal area. Potential impacts could include factors such as changes to existing or baseline conditions, as well as changes to future-without and future with project conditions. The USACE will continue to monitor and closely coordinate with other Federal and state resource agencies and local sponsors in determining how to best address any potential problems associated with the oil spill that may adversely impact USACE water resources development projects/studies. This could include revisions to proposed actions as well as the generation of supplemental environmental analysis and documentation for specific projects/studies as warranted by changing conditions.


Letter #5: U.S. Environmental Protection Agency (USEPA)

SEIS August 2010


Letter #6: Louisiana Department of Wildlife and Fisheries (LDWF)

SEIS August 2010 LDWF6-01: The appropriate Special Use Permits will be obtained from LDWF prior to construction of the project. LDWF6-02: We generally concur with the value of both of these suggestions. The planning development team considered the Wine Island “Rock Ring” alternative, as well as different protective hard structures as part of the alternative plan formulation process. If additional funding becomes available, the USACE would reconsider restoration alternatives and measures. However, the Wine Island “Rock Ring” and hard structure features were screened out during the plan formulation process. No additional alternative plan development or screening is anticipated due to Congressional-mandated completion dates for the LCA study reports by the end of 2010.


Letter #6: Louisiana Department of Wildlife and Fisheries (LDWF)

SEIS August 2010


Letter #7: Louisiana Department of Wildlife and Fisheries (LDWF)

SEIS August 2010 LDWF7-01: The appropriate Special Use Permits will be obtained from LDWF prior to construction of the project. LDWF7-02: We generally concur with the value of both of these suggestions. The planning development team considered the Wine Island “Rock Ring” alternative, as well as different protective hard structures as part of the alternative plan formulation process. If additional funding becomes available, the USACE would reconsider restoration alternatives and measures. However, the Wine Island “Rock Ring” and hard structure features were screened out during the plan formulation process. No additional alternative plan development or screening is anticipated due to Congressional- mandated completion dates for the LCA study reports by the end of 2010.


Letter #8: Terrebonne Parish Consolidated Government (TPCG)

SEIS August 2010


Letter #8: Terrebonne Parish Consolidated Government (TPCG)

SEIS August 2010 TPCG8-01: Concur. The planning process dictates development of a cost effective plan within the established budget. The proposed four-island NER plan was developed to better meet the mandate of the WRDA authorization. A seven-island plan would be ideal, but proved to be not cost effective. TPCG8-02: During the PED process such alternatives will be studied and considered for inclusion in the final design.


Letter #9: Louisiana Department of Environmental Quality (LDEQ)

SEIS August 2010


Letter #9: Louisiana Department of Environmental Quality (LDEQ)

SEIS August 2010


Letter #9: Louisiana Department of Environmental Quality (LDEQ)

SEIS August 2010


Letter #9: Louisiana Department of Environmental Quality (LDEQ)

-----Original Message-----From: Jamie Phillippe [mailto:Jamie.Phillippe@LA.GOV]

Sent: Wednesday, July 28, 2010 12:52 PMTo: Klein, William P Jr MVNCc: Melvin "Mitch" Mitchell; Renee SandersSubject: FW: LCA Amite - LDEQ Water quality Certification.William,This is a follow up e-mail to our phone conversation.A Section 401 water quality certification is required for federal licensesand permits, not environmental impact statements (EIS's). DEQ has submittedcomments to the Corps and DNR's Consistency Determination Section for the LCAprojects you mentioned.Please let me know if you have any further questions.Jamie PhillippeLouisiana Department of Environmental Quality401 Water Quality Certifications


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS10-01: PED will consider means of offsetting adverse impacts to EFH from the proposed construction, with the goal of minimizing those impacts while creating viable sustainable intertidal habitat. NMFS10-02: The Preconstruction Engineering and Design process will include consultation with natural resource agencies to ensure necessary habitat heterogeneity and function design measures are incorporated in the project.


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS10-3: The PED process will develop island design alternatives that address impact minimization. NMFS10-4: The PED process will develop island design alternatives that address habitat heterogeneity, stability, and longevity. NMFS10-5: The PED process will develop island design alternatives that address habitat heterogeneity, stability, and longevity. NMFS10-6: All concerned agencies will be consulted regarding timing of utilization of the Ship Shoal borrow areas in order to minimize impact to fisheries resources. NMFS10-7: Acknowledged. Previously submitted comments have been incorporated into the SEIS. NMFS10-8: Acknowledged.


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS10-9: Concur. There is an obvious trade-off to obtain the desired protection and long-term habitat values. NMFS10-10: Concur. The report indicates the desirability of the basin scale restoration. NMFS10-11: Concur. This is a policy issue beyond the scope of this report. NMFS10-12: This correction either has been or will be undertaken.


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS10-13: Sand fencing and vegetation palette and planting issues are described in Appendix L. NMFS10-14: Pertinent information from Dubois, et al. (2009) will be incorporated into the report and considered during PED. NMFS10-15: Concur. The date will be corrected. NMFS10-16: Pertinent information from Gelpi, et al. (2009) will be incorporated into the report and considered during PED. NMFS10-17: The date will be corrected. The blue crab nursery issue will be addressed. NMFS10-18: The table will be updated.


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS10-19: The desire for additional information is understood. The suggested revisions will be considered, time permitting. NMFS10-20: The figures will be verified and corrected, if needed. The suggested revisions will be considered, time permitting. NMFS10-21: The acreage figures will be verified and corrected, if needed. NMFS10-22: The acreage figures will be verified and corrected, if needed. NMFS10-23: The numbers will be correctly identified and verified.


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS10-24: Potential impact to blue crab population and fisheries will be considered during the PED process. This is an issue that requires interagency and intergovernmental coordination and cooperation, which will be emphasized. NMFS10-25: Concerns about the potential negative impacts to fisheries resources resulting from this proposed project are understood and appreciated. The referenced sections of the report will be revisited, time permitting, to further address the competing issues of short-term impact versus long- term benefit posed in this comment. The final acreage figures for impacted areas will be developed during the PED phase.


Letter #10: National Marine Fisheries Service (NMFS)

SEIS August 2010


Letter #11: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS11-01: 1)WRDA 2007 authorized only analysis of the barrier islands and prevented the project delivery team from analyzing measures on mainland habitat to the north. 2) The State and USACE are requesting additional authorization to construct the multiple island NER plan, but the authorized budget precludes us from recommending a multiple island plan for immediate construction. NMFS11-02: The report has been revised to include discussion of the NER plan in addition to the 1-island TSP.


Letter #11: National Marine Fisheries Service (NMFS)

SEIS August 2010 NMFS11-03: Acknowledged. Three sea level rise rates were applied to each alternative in the final array to assess WVA benefits. Uncertainties related to each rate were discussed in the Risk and Uncertainties section of the Integrated Feasibility Report. NMFS11-04: The State and USACE are requesting additional authorization for the NER plan and the additional benefits related to system-wide restoration have been discussed in the Integrated Feasibility Report. NMFS11-05: Acknowledged. The report has been revised to discuss impacts to blue crab. NMFS11-06: Plans and specifications will be coordinated with the USFWS and NMFS. Monitoring plans will also be consistent with the BICM program as outlined in the Adaptive Management report located in the Appendices.


Letter #11: National Marine Fisheries Service (NMFS)

SEIS August 2010


Letter #12: Natural Resources Conservation Service (NRCS)

SEIS August 2010


Letter #12: Natural Resources Conservation Service (NRCS)

SEIS August 2010 NRCS12-01: Though the initial benefits provided at construction are not retained throughout the period of analysis, the action does provide benefits out to TY50 that would otherwise be lost with the no-action alternative. In addition, while the TSP is only Whiskey Island, the State and USACE are requesting additional authorization to construct the NER plan. NRCS12-02: Acknowledged. The barrier island system is a naturally degrading system and hard- structural measures such as rock, revetment, and groins were analyzed to determine their effectiveness in sustaining the islands and preventing erosion. It was determined that beach/dune/marsh nourishment provided more benefits in the long term than hardened structures and that replenishment of material would have a longer-lasting effect in maintaining the islands over the 50-year period of analysis.


Letter #12: Natural Resources Conservation Service (NRCS)

SEIS August 2010


Letter #12: Natural Resources Conservation Service (NRCS)

SEIS August 2010 NRCS12-03: The project delivery team evaluated a wide-array of alternatives and eliminated measures based on a number of reasons as outlined in Chapter 3 of the Integrated Feasibility Study. While breakwaters have proven effective on Raccoon Island, our analysis did not indicate enough benefit for their inclusion in the TSP or NER. The team recognizes the benefits afforded Raccoon Island, but has yet to find a clear explanation of why/how these benefits occurred and therefore were unable to quantify the same benefits when modeling breakwaters on Whiskey Island.


Letter #12: Natural Resources Conservation Service (NRCS)

SEIS August 2010



APPENDIX H

VALUE ENGINEERING REPORT



Value Engineering Study Report

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

CEMVNVE0904

June 2009

Prepared by

Value Management Strategies, Inc.


Date: July 8, 2009

Frank Vicidomina, Value Engineering Officer

U.S. Army Corps of Engineers

New Orleans District

2608 Sells Street

Metairie, Louisiana 70003

Subject: Value Engineering Study Report  Final

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Mr. Vicidomina:

Value Management Strategies, Inc. is pleased to transmit 15 paper copies and

25 copies on CD of the Final Value Engineering Study Report.

This report summarizes the results and events of the study conducted May 5 

8, 2009, in New Orleans, Louisiana.

We enjoyed working with you and are looking forward to continuing our

efforts to assist the New Orleans District U.S. Army Corps of Engineers in its

value engineering efforts.

Sincerely,

VALUE MANAGEMENT STRATEGIES, INC.

Mark Watson, PE, CVS

VE Study Team Leader

Value Leadership

CORPORATE OFFICE:

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T: 941 323 5438

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Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Table of Contents

TABLE OF CONTENTS FINAL REPORT

EXECUTIVE SUMMARY .......................................................................................................... 1.1

INTRODUCTION................................................................................................................. 1. 1

VE STUDY RESULTS............................................................................................................ 1.1

Terrebonne Basin Barrier Shoreline Restoration .................................................1.1

Multipurpose Operation of Houma Navigation Lock ...........................................1.2

Convey Atchafalaya River Water to Northern Terrebonne Marshes...................1.2

General/Plan Formulation ....................................................................................1.3

SUMMARY OF VE ALTERNATIVE CONCEPTS.....................................................................1.3

VE ALTERNATIVE CONCEPTS.................................................................................................. 2.1

TERREBONNE BASIN BARRIER SHORELINE RESTORATION ...............................................2.1

MULTIPURPOSE OPERATION OF HOUMA NAVIGATION LOCK.......................................2.13

CONVEY ATCHAFALAYA RIVER WATER TO NORTHERN TERREBONNE MARSHES..........2.24

GENERAL/PLAN FORMULATION .....................................................................................2.32

PROJECT ANALYSIS................................................................................................................ 3.1

SUMMARY OF ANALYSIS................................................................................................... 3.1

KEY PROJECT FACTORS ..................................................................................................... 3.2

FUNCTION ANALYSIS / FAST DIAGRAM ............................................................................ 3.3

PROJECT INFORMATION........................................................................................................ 4.1

INTRODUCTION................................................................................................................. 4.1

PROJECT BACKGROUND.................................................................................................... 4.1

PROJECT DESCRIPTIONS.................................................................................................... 4.1

Terrebonne Basin Barrier Shoreline Restoration .................................................4.1

Multipurpose Operation of Houma Navigation Lock ...........................................4.3

Convey Atchafalaya River Water to Northern Terrebonne Marshes...................4.3

INFORMATION PROVIDED TO THE VE TEAM....................................................................4.5

IDEA EVALUATION ................................................................................................................ 5.1

INTRODUCTION................................................................................................................. 5. 1

PERFORMANCE ATTRIBUTES ............................................................................................ 5.1

EVALUATION PROCESS ..................................................................................................... 5.2

IDEA EVALUATION ............................................................................................................ 5.2

VALUE ENGINEERING TEAM AND PROCESS ........................................................................... 6.1

VE TEAM AND PROCESS.................................................................................................... 6.1

MEETING ATTENDEES ....................................................................................................... 6.3


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Table of Contents

APPENDICES

A. Coastal Impact Assistance Program Application  Houma Navigation Canal Lock, May 22, 2006; Terrebonne

Levee Conservation District

B. Conceptual floating barge gate designs

C. VE Study  Bayou Lafourche Siphon Restoration Project, July 2001; Proposal C1

D. Preparation of a MultiProject Environmental Assessment to evaluate the potential environmental impacts

associated with the removal of sand resources from Ship Shoal, offshore Central Louisiana

E. Louisiana Sand Management Working Group Meeting Minutes, 2 February 2005

F. Information on Relative SeaLevel Rise as prepared by Kevin Knuuti, P.E., Chief, Engineering Division, U.S.

Army Corps of Engineers, Sacramento, CA

G. MultiPit Breakwaters, Journal of Waterway, Port, Coastal, and Ocean Engineering, William G. McDougal,

A. Neil Williams, and Keizo Furukawa, January/February 1996

H. MMS Management of Outer Continental Shelf Material Deposits and related information


EXECUTIVE SUMMARY


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Executive Summary  1.1

EXECUTIVE SUMMARY FINAL REPORT

INTRODUCTION

This Value Engineering (VE) Study Report summarizes the events of the VE workshop conducted May 5  8,

2009 for the U.S. Army Corps of Engineers (USACE), New Orleans District, by Value Management Strategies,

Inc. The subject of the study was the Terrebonne Basin Barrier Shoreline Restoration project, the Houma

Navigation Gate Operations Plan, and the Convey Atchafalaya River Water to Northern Terrebonne Marshes

project.

This study was conducted at the Feasibility Scoping Report/Preliminary Draft EIS, an early stage of project

development, and as such is the beginning of plan formulation.

VE STUDY RESULTS

The VE team developed 38 alternative concepts which are intended to assist the USACE in better formulating

plans to carry forward into the next phase of development.

These recommendations are categorized per subject project as well as those that pertain to general plan

formulation.

Major findings of the workshop are summarized as follows:

Terrebonne Basin Barrier Shoreline Restoration

The natural processes of subsidence and erosion have combined with humancaused effects leading to

significant shoreline retreat and land loss along the Terrebonne Basin barrier island chain. As such, the system

is in a continuous need of sediment. The current project plans and budget only allow for a single

renourishment after about five years, which means the sustainability of the project is in doubt. Furthermore,

the availability of suitable sediment from Ship Shoal to restore and maintain the barrier islands may be limited.

Finally, the barrier island chain forms a complex system of ecological, physical, chemical, and social processes,

which interact in a highly involved and, at times, dynamic fashion.

Key VE alternatives identified to address these issues are as follows:

Sustain Barrier Island System

o Obtain a clear definition of the project objectives regarding sustainability

o Establish permanent trust fund for renourishment costs

Provide Sediment for Renourishment

o Use Minerals Management Service (MMS) to regulate Ship Shoal quantities to various projects needing

sediment

o Construct a permanent pipeline from Ship Shoal to the east end of East Timbalier Island


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Executive Summary  1.2

o Utilize Dynamic Coastal Systems

o Utilize sand recycling/backpassing for barrier island nourishment

o Consider coastal geomorphic processes for sediment placement

o Construct new barrier island chain closer to new shoreline

Protect Sediment

o Install inverted breakwaters and use excavated material to construct/replenish back marsh

o Fix barrier islands in their current location, eliminating or minimizing island roll over, by incorporating a

hard core or allow surface armoring

Multipurpose Operation of Houma Navigation Lock

The Houma Navigation Canal (HNC) lock and floodgate were planned over a decade ago. The possible addition

of a yearround significant freshwater flow into the HNC from the proposed Atchafalaya River Diversion Project

would significantly affect the operation of the lock and floodgate and perhaps even warrant reconsideration of

the facility design. The lock and gate complex will have to balance the impacts to navigation with the necessity

of protecting the interior from tidal surge and salinity. Finally, the potential future global sea level (GSL) rise

impacts what type of facility should be constructed.

Key VE Alternatives identified to address these issues are as follows:

Optimize holistic system by balancing HNC flow rate capacity with gate and lock design and operation plan

Develop a set of guidelines for when gate will be shut and install monitors and controls to automatically

close gate

Configure proposed 250foot floodgate such that an additional gate could be added in the future in order

to upgrade to a lock to accommodate a possible higher than expected future sea level

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Issues with this project are that freshwater and sediment has poor delivery to the wetlands due to 1)

alterations in natural hydrologic flow (canals, etc.), 2) constrictions in the Gulf Intracoastal Waterway (GIWW)

that reduce freshwater flow to the subunit, and 3) freshwater delivered to the HNC bypasses adjacent

wetlands and delivers to the Gulf of Mexico. The project is also having to identify where the freshwater

needed should be derived from and how it should be delivered to the areas that need it.

Finally, seasonal differences in the need for freshwater and nutrients, and the locations from which freshwater

can be recruited and distributed, may have conflicting parameters (i.e., freshwater is particularly needed

during periods of low flow in the rivers).


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Executive Summary  1.3

Key VE alternatives identified to address these issues are as follows:

GIWW Constriction at Houma

o Louisiana Department of Transportation and Development (LADOTD) to build a highrise bridge and

take the tunnel out of service

o Install a channel section through the Twin Span bridge

Address Freshwater Quantity Limitations

o Alter Old River Control Structure to divert more than 70/30 allocation

o Develop a seasonal freshwater management plan

o Install wicker gates on HNC cuts into the marsh

Address Freshwater Source and Transport

o Use Bayou Lafourche to convey freshwater to the northern Terrebonne marshes

General/Plan Formulation

Develop Plan Strategies that account for much higher levels of GSL rise

One issue addressed by the VE team spans all three projects and has ramifications throughout the

Louisiana Coastal Area (LCA) program. All three projects are currently assuming a minimum amount of

relative sea level rise (combination of sea level rise and subsidence). Currently, work is underway by the

USACE, National Oceanic and Atmospheric Administration (NOAA), and United States Geological Survey

(USGS) to investigate the glacial melt contribution to future GSL rise. Project benefits depend upon

habitats maintained above sea level. Consequently, benefits beyond the 50year planning horizon will be

lost if subsidence and GSL rise exceed the current assumptions. The rate of GSL rise in the future is

currently unknown, but could be much greater than the current assumptions. As such, the projects should

develop specific Plan Strategies that consider the range of possible future GSL rates.

SUMMARY OF VE ALTERNATIVE CONCEPTS

The table that follows summarizes all of the alternative concepts developed by the VE team. The items in red

text were identified by the VE team as items of particular note and key recommended strategies for the

Project Development Team (PDT) to consider.


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SUMMARY OF VE ALTERNATIVE CONCEPTS

Terrebonne Basin Barrier Shoreline Restoration, Multipurpose Operation of Houma Navigation Lock,

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Number Description

Terrebonne Basin Barrier Shoreline Restoration

T1 Install inverted breakwaters and use excavated material to construct/replenish back marsh

T2 Obtain a clear definition of the project objectives regarding sustainability

T3 Establish permanent trust fund for renourishment costs

T4 Construct a permanent pipeline from Ship Shoal to the east end of East Timbalier Island

T5 Conduct offshore sediment analysis to identify alternative sources of barrier island

renourishment sediment

T6 Consider windpowered fixed dredged sediment supply

T7 Use MMS to regulate Ship Shoal quantities to various projects needing sediment

T8 Consider coastal geomorphic processes for sediment placement

T9 Utilize sand recycling/backpassing for barrier island nourishment

T10 Fix barrier islands in their current location, eliminating/minimizing island rollover, by

incorporating a hard core (e.g., buried sandfilled Geotubes, revetments) or allow surface

armoring (e.g., revetments, rock, concrete)

T11 Construct groins and/or breakwaters with prefilled sediment

T12 Construct new barrier island chain closer to new shoreline

T13 Establish an environmental dredging fleet

T14 Prioritize project components based on marsh loss factors

T15 Add Plan Strategy that addresses habitat needs in excess of budgetary limitations

T16 Implement oil/gas industry outreach program regarding future sediment management

T17 Change the term nonstructural in project documents to soft structural

Houma Navigation Gate Operations Plan

H1 Optimize holistic system by balancing HNC flow rate capacity with gate and lock design and

operation plan

H2 Develop a set of guidelines for when gate will be shut and install monitors and controls to

automatically close gate

H3 Install flow control on HNC cuts into the marsh

H4 Configure proposed 250foot floodgate such that an additional gate could be added in the

future in order to upgrade to a lock


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Number Description

H5 Extend utilization of temporary barge gate and defer construction of new sector gate

H6 Consider using a floatable barge gate in lieu of a sector gate

H7 Construct concrete sector gates or utilize other maintenancefavorable materials

Convey Atchafalaya River Water to Northern Terrebonne Marshes

A1 Address flow constrictions in the GIWW at Houma

A2 Operate the Old River Control Structure to optimize flow split outside of the 70/30 mandate in

nonflood conditions

A3 Use City of Houma wastewater effluent to replenish cypress forests

A4 Pump flow from Davis Pond Diversion from Company Canal

A5 Use Bayou Lafourche to convey freshwater to the northern Terrebonne marshes

A7 Ensure that local fishing interests are fully informed of project alternative impacts

A6 Construct miniWoodys Ditch east of Houma and west of Bayou Lafourche connecting the

Mississippi River to Lake Fields

A8 Require oil companies to plug canals connecting to GIWW

A9 Install nutria fencing along GIWW and birth control measures throughout project area

General/Plan Formulation

G1 Develop Plan Strategies that account for much higher levels of global sea level rise

G2 Develop a seasonal freshwater management plan

G3 Create federal advisory committee

G4 Identify and incorporate the effects of subsidence from fluid withdrawal in the project analysis

and design; utilize water injection to minimize the impacts of fluid withdrawalinduced

subsidence

G5 Consider alternate procurement methods for construction


VE ALTERNATIVE CONCEPTS


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VE ALTERNATIVE CONCEPTS FINAL REPORT

TERREBONNE BASIN BARRIER SHORELINE RESTORATION

T1 Install inverted breakwaters and use excavated material to construct/replenish back marsh

This project faces a severe shortage of suitable material for island/dune construction as well as the back

marsh. A potential good source of back marsh material may exist just offshore of the barrier islands on the

Gulf side. This material can easily be dredged and placed on the land side of the island as the base for the back

marsh. With this excavation comes another advantage, the construction of an inverted breakwater on the Gulf

side in front of the island.

The construction of inverted breakwaters parallel to the beach is a simple concept that could prove to be very

cost effective as well as physically effective for normal wave activity. They could even be constructed in

tandem with offshore shoals. The concept is depicted in the sketch below.

The argument against inverted breakwaters is that the inverted breakwaters may trap some of the sand

eroding from the beach, and thus negatively impact the littoral drift. However, the current littoral drift carries

minimal sediment so the effect downdrift should also be minimal.

The advantage of this approach is the potential for obtaining sediment close to points of placement at a lower

cost to the project. In addition, the initial wave heights will be diminished by the inverted breakwater,

reducing impact energy along the shoreline and allowing more time for stabilization of plantings. Over time it

is probable that movement of sediment will fill in the inverted breakwater because, at this location, there is a

decrease in wave energy and the trench acts as a sediment trap. But this could be seen as a benefit as these

trenches would become excellent locations for material needed in future maintenance dredging to renourish

and sustain the program.

A paper published in the Journal of Waterway, Port, Coastal, and Ocean Engineering (January/February 1996)

entitled MultiPit Breakwaters by William G. McDougal, A. Neil Williams, and Keizo Furukawa assessed the

benefits of a submarine depression used as a breakwater. They found that the appropriate selection of

depression (pit) dimensions and placement may lead to a significant reduction in wave height behind these

structures. The shadow region behind the pits can reduce the wave heights by 10% to 20% of the incident

wave height. This paper provides guidance on the selection of pit (inverted breakwater) geometries and

placement for optimal breakwater performance. A copy of this paper is provided in Appendix G.


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These features would not be very effective in reducing significant storm surges, in the same manner that

offshore rock breakwaters would not be effective either. Further modeling and/or test reaches are

recommended to assess their applicability to this project.

T2 Obtain a clear definition of the project objectives regarding sustainability

The first environmental operating principle of the USACE states that the USACE should, Strive to achieve

environmental sustainability, and recognize that an environment maintained in a healthy, diverse, and

sustainable condition is necessary to support life. The sixth item listed in the 12 Actions for Change

indicates that the USACE should focus on sustainability. It is clear from these principles and actions that

sustainability is important to the USACE and, consequently, should be incorporated into USACE activities.

However, the April 2009 Feasibility Scoping Meeting Report (FSMR) does not contain any mention of how

sustainability will be considered in plan formulation. Moreover, there is no definition of sustainability

provided in the FSMR. A clear definition of sustainability is needed in order to make sustainability a

meaningful project objective.

Such an objective may be established as follows:

Sustainable with resources within the LCA up to the Year 2100 based on a range in relative sea level rise

(e.g., extrapolation of historical rates of sea level rise, accelerated rate of sea level rise per NRClow I, and

accelerated rate of sea level rise per NRChigh III) no matter what the cost.

T3 Establish permanent trust fund for renourishment costs

GSL rise at the highest rates combined with subsidence could be a net rise of nearly 6 feet by Year 2100 and

thus inundating the project area. If the LCA projects are not cancelled by Congress for these reasons, then an

alternative concept requires repeated fill and restoration efforts to keep pace with both GSL rise and

subsidence. This is not a sustainable condition, but demands continuous repeated beach renourishment and

marsh platform fill in perpetuity. Placing fill at the rate that equals the combined faster rate of GSL rate based

on this current science, and the known subsidence rates, in perpetuity will be vital for restoration success.

Consequently, episodic (e.g., every five years) marsh platform fill and barrier island sand nourishment is

essential for ecological restoration success. Project renourishment needs based on just the National Ecological

Restoration (NER) process using costeffective incremental cost accounting (CEICA) justification cannot provide

for perpetual ecological needs.

Congress typically chooses not to undertake financial obligations requiring future funding for perpetual costs.

But Congress may appropriate funds to establish a permanent trust fund and the interest accrued would

provide for perpetual costs. While such costs may be included as operations and maintenance (O&M) costs

provided by state, not federal, funding, then only state assets, not national assets, are accessible. However,

support is growing in Congress for certain permanent trust funds, for residential housing for example, that

would build on successful trust fund models by states and tribes. By far the largest is the $26 billion Alaska

Permanent Fund.

A possible example for a beach renourishment permanent trust fund: A multivariant analysis of the costs to

assure dredging and placement of sand from Ship Shoal to the Terrebonne barrier islands based on the above

various rates of GSL rise is performed to determine the projected range of perpetual funding needed. If, for

example, an annual beach renourishment cost of $5 million is required to keep pace with the accelerated rate

of GSL rise, then a permanent beach renourishment trust fund of $166 million yielding 3% annually would be


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needed. (Should this trust fund yield exceed renourishment requirements, the trust fund may grow or

alternatively annual net excess can be returned to the U.S. Treasury.)

References: NOAA, Sea Levels Online. http://tidesandcurrents.noaa.gov/sltrends/sltrends.shtml

T4 Construct a permanent pipeline from Ship Shoal to the east end of East Timbalier Island

One of the potential methods for barrier island construction and renourishment being considered by the PDT is

to create feeder beaches that may erode into the littoral drift transferring sand to be deposited on barrier

islands to the west. The primary location for such a feeder beach would be the east end of East Timbalier

Island. Typically, this would involve periodically bringing in a dredge to Ship Shoal, laying a pipeline, and

transferring sand to the feeder beach.

If the design team determines that there is benefit to identifying a permanent location for deposition of

renourishment sand at East Timbalier Island, it may be possible to lay a permanent pipeline for the dredge to

hook up to. The pipeline could terminate on land, though this may create an issue with excessive

accumulation of sand in a small area that might plug the pipe and prevent full deposition of the desired

volume of sand. It may be preferable to terminate the sand within the littoral drift current itself rather than on

dry land so that the sand begins its journey to the west immediately after it exits the pipe. A key concern

would be siting the pipeline to avoid or minimize impacts to existing oil and gas facilities located between Ship

Shoal and East Timbalier Island.

A further refinement of this idea would be to construct a permanent dredging plant at Ship Shoal to feed this

pipeline. This dredge could be powered by green technologies (wind, solar) as discussed in another

proposal.

T5 Conduct offshore sediment analysis to identify alternative sources of barrier island renourishment

sediment

The PDT has indicated that a major constraint in achieving the project objectives is the availability of suitable

sediment to restore and maintain the barrier islands. Although Ship Shoal was identified as a sediment source

with known reserves of sand, there are numerous projects in the LCA that are planning to utilize these

sediment resources. In addition, Ship Shoal is between 50 and 100 miles from the barrier islands depending on

the exact location within Ship Shoal and the island that is being restored with sand from this sediment source.

Consequently, the cost of restoring the islands could be reduced significantly if alternative sediment sources

closer to the islands were utilized for restoration activities. These sources may consist of sand layers located

beneath the top sections of nearshore bottoms.

It is suggested that an offshore sediment source investigation be conducted to identify alternative sources of

barrier island restoration and nourishment sediment. The investigation would focus on the area in the

immediate vicinity of the islands and on the side towards the Gulf of Mexico. It might be possible to tap into

the oil/gas industry for geological information (e.g., seismic recordings, geological logs, and sediment borings)

to assist in conducting this investigation, thereby reducing the costs of the investigation. In addition, this

recommendation could be used to suggest funding for the MMS to conduct this investigation for the purpose

of mapping the sediment resources in the area since MMS is the federal agency responsible for managing

these offshore resources.


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T6 Consider windpowered fixed dredged sediment supply

Dredging from Ship Shoal to the Terrebonne Islands will be by periodic use of hopper dredges mobilized and

demobilized every five to ten years.

This alternative concept involves the permanent placement of a cutter head pipeline dredge at Ship Shoal with

the pipeline terminus on East Terrebonne Island. Sand deposited here subtidally is expected to accrete to the

barrier islands by long shore displacement.

Two booster pumps (either kinetic or positive displacement) are needed to supplement the dredge pump due

to the distance the sand slurry can be pumped without pipe sedimentation. Two booster pumps would be

installed to form a series spaced equidistant from the dredge site to the disposal site. A displacement booster

pump used in combination with a centrifugal dredge pump would require a booster pump holding facility

because it is difficult to match positive displacement pumping rates to centrifugal pumping rates.

Offshore Louisiana has potential for wind energy development according to two reports prepared for the

Department of Energy in 1979. Offshore areas west of the Mississippi River offer a high Class 3/low Class 4

wind energy resource. (Class 7 being maximum and Class 3 is the threshold for feasible wind power

development.) In 2005, the Louisiana legislature approved authority for the State Mineral Board to lease state

lands and water bottoms (i.e., areas within three miles of shore) for the production of wind energy.

To power these slurry pumps, three 1.5 MW capacity wind turbines and towers would be installed: one at the

Ship Shoal cutter head and two others to power the booster pumps. Wind power supply is interruptible. Cut

in wind speed, when power is produced, begins at 3.5 m/s (8.4 mph). Because the windpowered electric

pumps would shut down when the wind is below the cut in speed, a flap valve at each booster station would

be installed to drain the slurry to prevent sediment build up in the pipe.

The installed price for each 1.5 MW wind turbine and tower is estimated at $17.5 million according to the

Danish Wind Industry Association. General Electric produced over 10,000 1.5 MW capacity wind turbines

successfully operating since 1996 and are manufactured at GEs Pensacola, Florida plant.

References:

Coastal Zone Wind Energy, Part II: Frequency Distribution of Winds by Direction for East and Gulf Coast

Stations, Final Report, DOE/ET/2027477/78/798, prepared by Michael Garstang and others, University of

Virginia, Charlottesville, VA, under contract for U.S. Department of Energy; May 1979.

Design Study and Economic Assessment of MultiUnit Offshore Wind Energy Conversion Systems Application,

Vol. 1: Executive Summary, WASH233078/4 (Vol. 1), prepared by Westinghouse Electric Corporation,

Advanced Systems Technology, East Pittsburgh, PA, under contract for U.S. Department of Energy; June 14,

1979.

Danish Wind Industry Association, http://www.windpower.org/en/tour/econ/econ.htm

General Electrics 1.5 MW Wind Series: 1.5xte and 1.5ste,

http://www.gepower.com/prod_serv/products/wind_turbines/en/15mw/index.htm

Louisiana HB 428 (Act 481), July 12, 2005.


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Note: The peak capacity of 4.5 MW for these three wind turbines, produced when wind speeds exceed 12

m/s, compares to the 10,400 horsepower main engine  equivalent to 8 MW of power  on the hopper dredge

WHEELER operated by the USACE. These wind turbines, with 82.5meter rotor length, can produce $400,000

annually in electric power revenue based on 8 cents per kWh and 30% operating efficiency. At some

additional cost, these wind turbines could be installed to provide electric power revenue to the project when

the power produced is not needed for dredging operations.

T7 Use MMS to regulate Ship Shoal quantities to various projects needing sediment

The proposed concept is to use the MMS to regulate the use of Ship Shoal sediments for use by various

projects, in particular coastal barrier island restoration. Included in the idea is the thought to have MMS

evaluate the actual quantities of available sediment at Ship Shoal and determine appropriate locations for its

use.

BACKGROUND: Following a request by the USACE to be a Cooperating Agency in the LCA Barataria Basin

Barrier Shoreline Restoration, the MMS has been working with the USACE and other federal and state natural

resource agencies regarding the use of Ship Shoal and other sand bodies under their jurisdiction for use as

sand sources for coastal restoration projects. Working as a Cooperating Agency for the LCA Barataria Basin

Barrier Shoreline Restoration, the MMS determined the need for intensive coordination and management of

offshore sand resources for use in coastal Louisiana restoration projects. In May 2003, Mr. Barry Drucker with

the MMS established the Louisiana Sand Management Working Group (LASMWG) with the intent and

purpose of bringing together various federal and state natural resource agencies, as well as potential sand

resource users (see Appendix E). S. Jeffress Williams, U.S. Geological Survey (Coastal and Marine Geology

Program, 384 Woods Hole Rd., Woods Hole, MA 02543, email: jwilliams@usgs.gov) provided a compelling

summary of the problems and opportunities at the meeting:

1. Need for longterm sand requirements: Use of offshore sand for nourishment and coastal restoration

in Louisiana, as well as many other regions, has longer term implications than just 20 to 30 years. The

USACE projects are typically authorized for 50 years. For several projects suitable and economical sand

resources have not been identified for 50 years of initial fill and periodic O&M fills. In my judgment, we

need longer term planning for compiling sand needs. At minimum 50 years, 100 years is best.

2. Need for sediment database/Seafloor maps: For Louisiana in particular, a great deal of data and

information is available from very disparate sources on sand body location, sand quality, and quantity.

What is needed is a comprehensive computerbased sediment database. The usSEABEDsystem is one

start in this direction, but it needs further development to incorporate subbottom data, i.e., cores,

borings, and seismics. Also, at least for premier sand bodies like Ship Shoal, Tiger Shoal, etc., we need

complete map coverage of the seafloor using digital mosaic sidescan and multibeam technologies

that have recently become available. Such base maps are critical for not only accurately delineating

the sand bodies, but also important for mapping essential fish habitats and infrastructure to avoid,

such as pipelines.

3. Permit streamlining: Plans for large scale barrier nourishment are well advanced in Louisiana,

potentially requiring ~100 CY meters of sand. An efficient permitting process by the USACE and MMS

needs to be in place.

4. Science studies/monitoring: Important questions arise on sediment transport processes associated

with dredging and nourishment, such as: What is the traditional engineering "closeout depth" for a


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particular coast and how close to shore can you dredge without exacerbating erosion of the adjacent

coast? What is the importance of ebbtide shoal sediments for the Louisiana sediment budget and can

they be mined without causing downdrift erosion? What is the optimum spatial and temporal design

for dredging so as to minimize environmental harm? How long do dredge holes remain open? What is

their short and longterm effects on marine habitats, wave refraction, etc.?

In May 2003, the MMS provided in the Federal Register a notice to prepare a multiproject environmental

assessment to evaluate the potential environmental impacts associated with the removal of sand resources

from Ship Shoal (see Appendix D). Meetings were conducted over the ensuing years with MMS funding

scientific efforts to investigate the potential impacts associated with removal of sand resources from Ship

Shoal.

IMPLICATIONS FOR CREATIVE IDEA: The MMS is the regulatory agency with jurisdiction to manage the Ship

Shoal and other offshore federal sand bodies. They have been conducting investigations over the past several

years. There have been several studies funded by the MMS that have determined the extent of sand and

other mineral resources on Ship Shoal. The MMS has funded and will likely continue to fund studies regarding

potential impacts of removing these sand resources from Ship Shoal on aquatic organisms, as well as on wave

dynamics. However as described in the attached minutes of the May 2003 meeting, the MMS does have

authority to make decisions on suitability or priority of sand use; however, the MMS would prefer consensus

on these decisions. Hence the creation of the LASMWG.

Most recently (see email below), Ms. Stacie Merritt of the MMS notified intent to conduct a meeting for the

LASMWG this Summer in New Orleans, Louisiana. The intent of the meeting is to discuss issues associated

with accessing federal sand and gravel resources for projects along the Louisiana coast.

-----Original Message-----

From: Merritt, Stacie [mailto:Stacie.Merritt@mms.gov]

Sent: Thursday, May 07, 2009 4:36 PM

Subject: Louisiana Sand Management Working Group Meeting - Summer 2009

The Minerals Management Service, Marine Minerals Program is planning a

meeting for the Louisiana Sand Management Working Group this Summer in New

Orleans, Louisiana. The intent of the meeting is to discuss issues

associated with accessing Federal sand and gravel resources for projects

along the Louisiana coast. Below is a draft list of meeting topics:

1. A Marine Minerals Program Case Study: Pelican Island

2. Gulf of Mexico Significant OCS Sediment Resources NTL

(http://www.gomr.mms.gov/homepg/regulate/regs/ntls/2009NTLs/09-g04.pdf)

3. Need for OCS Mineral Resources

4. Geological and Geophysical (G&G) Authorization Requirements

5. Methodology and Potential for Submerged Cultural Resources in Borrow Pit

Areas

We invite you to comment on the above list of topics and to suggest

additional topics you would like covered at the meeting.

Comments/suggestions should be sent to Stacie Merritt at

stacie.merritt@mms.gov by June 5, 2009.

We would also like you to provide input on the dates for the meeting. We

are currently considering holding the meeting during the August 3  August


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28, 2009 time period. Please go to the following link to enter your dates

of availability. Make sure you scroll to the right to see all of the days.

http://www.doodle.com/6rkmyvkiswfugkm6

If none of these days will work for you, please provide other dates for

consideration. Dates of availability and proposed alternative meeting dates

are due by June 5, 2009.

Once we have an idea of how many people are interested in attending and how

extensive is the list of topics, we will be able to determine the specifics

on when it will be held and where.

If you know of anyone who should be added to this mailing list (or deleted),

please send their contact information to Stacie Merritt

(stacie.merritt@mms.gov); their name will be added to future mail outs.

We look forward to your participation in this meeting.

Thanks,

Stacie

Stacie M. Merritt

Marine Minerals Program Coordinator

Minerals Management Service

Coastal Program Section

504-736-3276

VE Alternative followup:

In June 2007, MMS sent a letter to all stakeholders (Federal, State, and other) requesting information on

potential projects using outer continental shelf (OCS) sand and gravel resources in the next five years. Based

upon MMS resources and stakeholders' responses regarding project timelines, a maximum of two projects per

quarter were scheduled.

Most recently, MSS sent another request in April 2009 to update the calendar; responses were due June 1,

2009. Their intent is to publish the responses in the Federal Register in the third quarter of 2009. It is

anticipated that MMS will continue to schedule a maximum of two projects per quarter.

An email from Stephanie M. Gambino with MMS is provided in the appendices of this report. The email

provides information regarding MMS management of OCS deposits, as well as material resource evaluations

and studies specific to Ship Shoal.

T8 Consider coastal geomorphic processes for sediment placement

The configuration and manner in which sediment will be placed on the barrier islands was not presented in the

April 2009 FSMR. It appears that the PDT is leaning towards placement of most sediment (sand on the Gulf

side and mud on the bay side) on the downcoast side of the islands, which is the western end of each island.

This preliminary decision is apparently based on the fact that the longshore transport moves sediment from

east to west. Likewise, from a crossshore standpoint it does not appear that much consideration has been

given yet to how the sediment would be placed from the beach across the dune and into the backbay marsh.


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It might be possible to increase the longevity of the placed sediment by considering the coastal geomorphic

processes in developing and/or refining the configuration and manner of sediment placement.

Instead of placing sand in equal amounts along the entire length of the island or in larger volumes at the

western end of each island, the PDT should consider constructing the east end of each island wider than the

west end. Utilizing this configuration for the beach restoration and nourishment activities would allow the

eastern beach area to serve as a feeder beach providing a sediment source to nourish downcoast (western)

beaches as the longshore transport moves the sand from east to west. Prior to implementation, a coastal

processes analysis should be conducted to determine the maximum beach width in each area to avoid

overbuilding the beach in the eastern portions of each island. An overbuilt beach could push the sand into

deeper waters and/or result in overly steep beach slopes, both of which could increase the rate of erosion.

Another consideration in the placement of sediment for island restoration is the aspect ratio of each barrier

island. The aspect ratio is the length of each island divided by the width and it can be calculated as a mean or

at regular intervals (e.g., every quarter mile) along the entire length of each island. There has been some

research conducted to estimate the optimum aspect ratio for the barrier islands and this information should

be considered in the development of sediment placement configurations (volumes and locations).

T9 Utilize sand recycling/backpassing for barrier island nourishment

Beach restoration and beach nourishment are presented in the April 2009 FSMR as two management

measures that will be carried forward for future consideration in the formulation of project alternatives.

Beach restoration is defined in the FSMR as the (initial) placement of beachsuitable sediment (sand) within

the beach profile from the dune out to the depth of closure, while beach nourishment is defined as the

periodic placement of sand in the same location. Beach restoration basically restores the shoreline and beach

to historical conditions, while beach nourishment keeps pace with future erosion to maintain the restored

condition. Ongoing beach nourishment activities will require the identification and dredging of additional

sources of sand in the future. Based on existing information and data, sand is already limited in availability and

there is a lot of demand for that sand for this project as well as other projects in the LCA. Therefore, the

retention and efficient use of existing and future sand resources will be an important factor in costeffectively

meeting project objectives.

One way to make more efficient use of existing and future sand resources is to utilize sand

recycling/backpassing to replace and/or augment beach nourishment activities. In the Terrabonne Barrier

Islands, the net longshore transport is from east to west, meaning that sand is driven by the waves from east

to west. Sand recycling would consist of dredging sand at the western end of the barrier islands and placing it

on the eastern end. This would help reduce the quantity of new sand needed for future nourishment

activities. The effectiveness of sand recycling can be improved through the construction of terminal groins or

breakwaters at the downcoast end of the barrier islands to capture as much sand as possible before it is lost to

the bay area and/or Gulf of Mexico. Prior to implementation, coastal processes analyses should be conducted

to make sure that sand from an upcoast island (i.e., to the east) is not providing a substantial source of sand to

a downcoast island, otherwise the sand recycling program might result in increased erosion to the downcoast

barrier island. Sand recycling has been used with success along Peninsula Beach, which is located in Long

Beach, California.


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T10 Fix barrier islands in their current location, eliminating/minimizing island rollover, by incorporating a

hard core (e.g., buried sandfilled Geotubes, revetments) or allow surface armoring (e.g., revetments, rock,

concrete)

The natural geomorphic development of barrier islands is to allow them to rollover where the dune field

progresses landward overriding the back marsh as the beach face erodes. This is currently the preferred

design as presented by the USACE PDT. In order for this approach to be successful, periodic renourishment

(typically every five years) is required over the 50year life of the project to maintain both the barrier island

and the back marsh. However, the current project plan and budget only allows for a single renourishment

after about five years, which means the sustainability of the project is in doubt.

An alternative approach is to fix the islands in place and minimize the amount of renourishment required. This

is not a natural geomorphic process for barrier islands as it limits rollover and migration of the barrier island

landward. However, there are agencies in the state, as well as members of the general public, who would

prefer this approach as a more positive means of providing storm surge and salinity intrusion protection.

Fixing the location of the islands with a corresponding reduction of renourishment needs may improve

sustainability within the available budget for the project. It would also reduce the amount of material needed,

which is a considerable general project concern.

One alternative installs a buried hardscape that draws a lineinthesand on the shoreline. The sandfilled

Geotube (using sand already earmarked for beach and dune restoration) would resist erosion of sand along

with storm surgerelated breaches in a more costeffective manner than, say, offshore breakwaters. In most

cases these Geotubes can replace the offshore breakwaters, or be used in tandem with the breakwaters (such

as inverted breakwaters proposed above) in critical areas.

Since the Geotubes are not exposed most of the time, they will not experience deterioration from sunlight or

vandalism. If damage to the Geotubes occurs from storm surge activity, they can be replaced or repaired.

Erosion of the sand in front of the Geotubes and on top will likely occur over time requiring renourishment of

the dunes approximately every ten years. A sketch of this concept is shown below:

In lieu of Geotubes, other hardened materials such as revetments or rock can be buried in the core to increase

the hardness of the island. Further, surface hardening can be considered through the use of surface

revetments, concrete, or rock; however, this approach may not be preferred over the hardened core

concept as it would take away from the sand beach surface that may be preferred nesting areas for birds. In

addition, surface hardening would be considered to be less aesthetic than exposed sand surfaces, and would

be less capable of supporting stabilizing vegetation.


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T11 Construct groins and/or breakwaters with prefilled sediment

The use of groins and breakwaters to trap sand on the barrier islands were identified as potential management

measures to be carried forward through the plan formulation phase. Based on the information presented in

the April 2009 FSMR, it appears that groins and breakwaters would be implemented without the use of prefill.

The implementation of groins and breakwaters without prefill can lead to erosion of adjacent shorelines and

beaches as indicated in the FSMR. This erosion is caused by the trapping (or retention) of sand in the fillet of

the groins, as well as the salient (or tombolo if the salient touches the shoreline) of the breakwaters.

The addition of prefill should be considered to address the potential impact of erosion attributed to the

implementation of groins and breakwaters. For groins, the use of prefill would entail estimating the volume of

sand that would be trapped in the fillet and then placing this volume of sand in the fillet as part of the initial

groin construction project. In the case of the breakwaters, the use of prefill would consist of estimating the

volume of sand that would be trapped in the salient and then placing that volume of sand in the salient as part

of the initial breakwater construction project. The use of prefill mitigates for impacts to adjacent beaches

while the retention structure (i.e., groin or breakwater) provides a wider, more stable beach. Prior to

implementation of prefill for a breakwater, a coastal processes analysis should be conducted to assess the

potential impact of the salient itself on longshore transport.

T12 Construct new barrier island chain closer to new shoreline

There is high probability that maintaining the existing barrier islands beyond the 50year planning horizon will

not be possible due primarily to increasing rates of sea level rise, future subsidence, and resources constraints

(e.g., sediment supply and funding). Given the value of the habitat on the islands, as well as the important role

these islands play in protecting bayside resources, it still makes sense to expend resources in restoring and

maintaining the islands from now and into the immediate future (e.g., 50 years). However, it also makes sense

to begin thinking now about the longterm sustainability of the entire ecosystem in the LCA.

It is suggested that consideration be given to the design and construction of a new barrier island chain. This

would include the identification of a new fallback shoreline that would be used to guide the location of the

new barrier island chain. This new shoreline and barrier island chain would form the second line of defense,

with the first line of defense being the restoration and protection of the existing barrier islands. The new

barrier island chain could be constructed in areas of the existing LCA that are relatively high in elevation and

free of oil and gas wells and pipelines to minimize construction costs associated with fill placement and

construction access. In addition, this strategy could be implemented through an adaptive management

framework such that lessons learned from restoration and maintenance of the existing barrier islands could be

used to improve the design, construction, and maintenance of the new barrier island chain.

T13 Establish an environmental dredging fleet

The amount of sediment needed to renourish the barrier island system will far exceed the available dredge

fleet in and beyond the region. While private industry will respond to this need by manufacturing additional

dredges as projects progress, it is likely that such plant development will severely lag project demand. Private

industry will not likely produce more than is needed at any given period, as they will perceive a risk of over

supplying intermediate need. Such projected constant shortages will likely limit bid completion and raise

prices substantially.


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A possible means of avoiding this problem may be government partnerships with private industry to fabricate

new dredges in advance of individual project need. For example, the government could build the needed fleet

and lease the equipment to industry; the government could finance industry to build their fleet; or industry

could build the fleet on their own and lease equipment to the government. There are a number of

lease/purchase and other innovative procurement options that balance risk and optimize financial

advantages between the government and industry. In general, the government can secure capital at relatively

low cost and industry can take tax advantages of ownership via depreciation deduction. Such advance

fabrication of dredges could help in achieving adequate resource supply to meet projected demand.

T14 Prioritize project components based on marsh loss factors

The PDT indicated that some type of system would be needed to prioritize restoration activities. However, it

does not appear that such a system was developed or applied during preparation of the information contained

in the FSMR. The PDT was asked if an estimate had been developed that represents the percentage of marsh

loss due to the various causes of erosion. For example, how much of every 100 acres of marsh loss is

attributed to sea level rise, fluid withdrawalinduced subsidence, sediment compactioninduced subsidence,

windwave erosion, storminduced erosion, vegetation loss attributed to salinity changes, and herbivore

activity. Note that a cursory review of the figure in Attachment F of the April 2009 FSMR suggests a

relationship between oil and gas extraction (as represented by oil and gas wells) and marsh loss (as

represented by open water areas). It is important to develop an estimate of the importance of these various

loss factors because a primary stated objective of the barrier island restoration is to protect and preserve the

marsh to the north of the islands. If sea level rise and fluidinduced subsidence are of equal or greater

importance than windwave erosion and storminduced erosion, then restoration of the barrier islands may

not achieve this objective.

One way to address this issue would be to conduct an analysis to determine the amount of marsh loss

attributed to sea level rise, fluid withdrawalinduced subsidence, sediment compactioninduced subsidence,

windwave erosion, storminduced erosion, vegetation loss attributed to salinity changes, and herbivore

activity. The results of this analysis could then be used to prioritize project components, thereby giving the

PDT a planning tool for the prioritization task that they will have to undertake. The results might also suggest

that it is not possible to meet some of the project objectives or that the objectives themselves need to be

prioritized in order to select the appropriate restoration activities. Concern about the possible findings of this

analysis should not be used as a reason not to conduct it since the results will merely inform the decision

making process. For example, even if the results indicate that sea level and/or subsidence are primary

contributors to marsh loss, it does not mean that barrier island restoration should not be implemented, rather,

it means that barrier island restoration would probably not be effective in meeting the project objective

related to marsh protection from windwave erosion and storminduced erosion.

T15 Add Plan Strategy that addresses habitat needs in excess of budgetary limitations

The Plan Strategies identified for the project are intended to produce a full spectrum of alternative plans as

required by National Environmental Policy Act (NEPA) and USACE planning guidance in ER 11052100.

Alternative Plan Strategies were designed to be significantly different from one another and to represent the

entire range of solutions to identified problems within the study area. This VE alternative concept is intended

as a check to the PDT that Plan Strategy E, increase of current configuration and functional geomorphology, be

the Plan Strategy that addresses habitat needs above and beyond the budgetary limitations set by the project

authorization. During the NEPA alternative evaluation process, this consideration is needed regardless if the

funds will be available to ever make the alternative feasible. If Plan Strategy E is not intended to satisfy this


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part of the alternative evaluation, suggest developing an additional Plan Strategy that does address the best

case scenario regarding habitat creation and sustainment.

T16 Implement oil/gas industry outreach program regarding future sediment management

The PDT indicated that the oil/gas industry (industry) might redistribute sediment placed on the islands

following restoration activities. The industry has a longstanding practice of redistributing sediment to protect

oil/gas infrastructure. For example, the industry redistributes sediment via dredging to bury pipelines that

have become exposed following storm and hurricane activity. Consequently, the PDT expressed concern that

the industry would utilize the newly placed sediment for this purpose upon completion of restoration

activities, thereby decreasing the effectiveness of restoration activities and undermining project success.

An outreach program could be implemented to proactively address this issue. The outreach program would

explain the various restoration components to the industry. It would include a description of the natural

sediment processes and how those processes would benefit the natural habitat and resources, as well as how

those processes would benefit the industry. A description of acceptable sediment management practices

would be included in the outreach program to minimize negative practices and maximize positive practices

since it might be possible to work with the industry to help maintain and/or improve the islands upon

completion of restoration activities. Finally, the outreach program would have to be developed in careful

consideration of the target group that is to receive the information to make sure the right people in the

industry are getting the message and that it is tailored to those people. This will help ensure that the right

message is getting to the right people.

T17 Change the term nonstructural in project documents to soft structural

The project documents use the following definition of terms: A management measure is a feature (a

structural element that requires construction or assembly onsite) or an activity (a nonstructural action) that

can be combined with other management measures to form alternative plans. The term nonstructural is

commonly used in USACE flood control and hurricane protection projects. It has a very specific meaning that

includes options such as floodproofing property, raising buildings above flood elevations, purchasing property

and/or relocating or removing the property from the area of risk, and prohibition of further development in

areas of risk. However, for this project, the term is to refer to restoration activities that include:

Dune restoration

Marsh creation

Beach restoration

Beach nourishment

Subtidal sediment placement

Addition of sediment into nearshore environment to supplement littoral drift

Beach closure

Small marsh island construction on bayside for bird habitat

Vegetative planting

Herbivory control


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Biological bioengineered oyster reefs

Spit creation

Canal backfilling

In order to avoid confusion with a generally accepted definition, the VE team recommends that the term non

structural, as used in the project documents, be changed to soft structural.


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MULTIPURPOSE OPERATION OF HOUMA NAVIGATION LOCK

H1 Optimize holistic system by balancing HNC flow rate capacity with gate and lock design and

operation plan

The HNC lock and floodgate were planned over a decade ago. The possible addition of a yearround significant

freshwater flow into the HNC from the proposed Atchafalaya River Diversion Project would significantly affect

the operation of the lock and floodgate and perhaps even warrant reconsideration of the facility design.

The lock and floodgate have multiple purposes and functions (reference Coastal Impact Assistance Program

Application  Houma Navigation Canal Lock, May 22, 2006; Terrebonne Levee Conservation District, included

as Appendix A). First and foremost is providing a barrier to tidal (hurricane) flooding as an integral part of the

proposed Morganza to the Gulf levee system. The second function is to block excessive saltwater intrusion

into the basin. High saltwater levels adversely affect marsh habitat and potable water supply for the City of

Houma. As result of providing a barrier in the HNC, accommodations to minimize impacts to navigation are

incorporated in the design of the closure facility. A 250footwide (200 feet wide prior to recent change) gate

will allow safe passage of oil rig components and the 110foot lock would allow normal vessel traffic during

prolonged periods of closure.

The required operating frequency and duration of the 110foot lock may be greatly affected by the amount of

water (and consistency of this supply) that the proposed Atchafalaya River Diversion Project can produce. The

very need for a lock should also be reevaluated and balanced with the formulation of this project.

It may be determined that adequate freshwater flow can be supplied to the HNC, negating the need for

saltwater intrusion gate/lock closure. This could minimize lock operation frequency to an average of 20 days

per year (usually noncontinuous) due to historical flood events. The question arises as to whether or not such

minimal closure time warrants the need for vessel passage during such events as there are alternate (albeit

lengthy) alternative routes to the Gulf of Mexico.

On the other hand, significant freshwater flow in the HNC may be distributed out from the channel into

adjacent marsh if a relatively small hydraulic head is artificially maintained by means of closing the gate and

lock. This would require a lengthy (perhaps fulltime, all the time) operation of the lock.

The recommendation is to budget for fulltime lock operation (about $1.2 million per year) and integrate

Atchafalaya River Diversion alternative selection with HNC lock operation, design, and perhaps necessity. If

this is done, it may be determined that the Atchafalaya River Diversion may be efficiently maximized with a

resulting minimization of lock total life cycle cost. This may indicate that the set diversion project pre

authorization amount of $221 million be exceeded to achieve overall system costeffectiveness with a

reduction in HNC Lock life cycle costs. This could be complicated given two separate funding authorizations.

It should be noted that the HNC lock and floodgate complex is part of the Morganza to the Gulf, Hurricane

Protection Project. The parent project authorization is currently in abeyance pending approval of a Post

Authorization Change (PAC) report. This report is required due to an official project cost increase in excess of

20%. The PAC is currently being developed, but its scope is limited to only level of risk reduction (levee and

structure height) and not broader project parameters. Given the above mentioned significant existing and

possible future conditions changes relative to plan formulation criteria of a decade ago, the entire design of


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the proposed lock and floodgate should be reevaluated. A summary list several significant outstanding

questions pertinent to the lock and gate complex is as follows:

Would the introduction of a significantly higher flow of freshwater down HNC negate the need to provide a

barrier for nonflood event saltwater intrusion?

If higher flows are introduced down HNC, would closure result in beneficial distribution of freshwater

upstream of the facility (additional purpose/reason for a lock structure)?

If soon to be published USACEsanctioned predictions of net sea level rise is faster and higher than

previously anticipated, would it then be prudent to build a singlewide (250 foot) lock versus a wide

floodgate and smaller (110foot) lock combination?

The local sponsor apparently has requested a permit to construct a temporary standalone barge gate as

part of their levee construction plan. Can this serve for a longer period of time and defer construction of an

expensive sector gate? Also, if a single gate closure is (now) apparently acceptable to the local oil and gas

industry, why does the federal plan (still) require a lock and gate combination?

Does the cost estimate reflect, and is it consistent with, ongoing construction of large sector gates for the

IHNC East Closure and for the current design of the GIWW West Closure Complex?

H2 Develop a set of guidelines for when gate will be shut and install monitors and controls to

automatically close gate

The flood gate on the HNC is proposed to be closed for flood and salinity control. If the gate is closed, marine

traffic will be required to use the lock, thus resulting in possible delays to navigation.

Given the importance of the gate to safe navigation on the HNC as well as to the marshlands, and that these

two factors may compete against one another regarding whether the gate should be closed or not, an

automatic system should be considered that would close the gate at specific, predetermined levels of tidal

surge, salinity, and canal flow. This would serve to eliminate the possibility of one function of the gate

superseding the others.

H3 Install flow control on HNC cuts into the marsh

The Central  Lake Boudreaux Area problems and opportunities include major hydrologic alterations through

the presence of the GIWW and the HNC. However, one of the primary concerns within this study unit is the

altered hydrology and distribution of freshwater and sediment. Freshwater and sediment that reaches the

Central Study Area has poor delivery to the wetlands. If the project increases freshwater flow down the HNC

and cuts are made through spoil banks, it may be prudent to also install flow control at these openings. By

installing wickertype gates or other backflow preventer, the freshwater would not quickly drain back into the

HNC as flow diminishes. This alternative would allow control of freshwater returning into the HNC as flows

subside in that channel. Freshwater would then be available to drain out slowly through intermarsh

pathways.


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H4 Configure proposed 250foot floodgate such that an additional gate could be added in the future in

order to upgrade to a lock

If significant sea level rise becomes a reality, HNC closure will be required throughout the year. This may

negate the ability to safely pass platform structures through a single floodgate. It then may be warranted to

upgrade the proposed 250foot floodgate to a full lock with the addition of a second gate. Placement and

configuration of the initial floodgate should accommodate such a possible future modification. Navigation

approach reaches would be a primary factor to consider.

H5 Extend utilization of temporary barge gate and defer construction of new sector gate

The state and local levee district has plans to construct a temporary 250foot barge gate as well as a system

wide reduced height levee. The height of the gate would not provide desired 0.01 annual storm probability

containment, but still be on the order of 0.02 to 0.04. The subsequent federal project will increase this

protection to the 0.01 level. However, a very costly component, the 250foot floodgate (new sector gate)

could be left as a last order of construction or even be deferred for several years. The protection obtained by

the temporary gate would only allow wave overwash during peak hurricane hours and the vast storage of the

protected area could easily accommodate such inflow without any significant property damage. It would

therefore appear prudent to extend the service of the temporary floodgate until major maintenance is

needed.

An estimated breakout cost for the 250foot floodgate from URS Task Order 5, May 2008, is about $150

million. Estimated major maintenance cost would be about $5 million in ten years. Annual interest savings of

first cost and tenyear maintenance costs at the current federal discount rate of 45/8% would be

approximately $7 million per year of deferral.

H6 Consider using a floatable barge gate in lieu of a sector gate

In the initial project planning 10+ years ago, the premise was that a 200footwide sector gate was a favorable

choice versus a bargetype gate given easier and faster operation. VE studies then, and since that time, have

challenged this premise given the unproven performance of such a large sector gate. Major maintenance,

when the gate must be removed, is a significant concern for large sector gates. The USACE has chosen a 150

foot complementary barge gate design for the east GIWW closure current under designbuild construction. It

is still believed that a floating barge gate may be more appropriate, both in initial cost and long term costs, for

the now 250foot HNC gate. Several conceptual floating barge gate designs are illustrated in Appendix B.

H7 Construct concrete sector gates or utilize other maintenancefavorable materials

The standard gate material is steel protected by sacrificial anodes for corrosion resistance. The USACE

conducted an extensive value analysis assessment of the use of differing materials to construct gates (sector,

miter, tainter) along with techniques to reduce corrosion. This study was initiated after the recognition that

typical steel gates eroded easily and were difficult and expensive to repair and maintain. The results of this

study were published on August 13, 2004 in a value engineering report entitled Improving Life Cycle Costs of

Construction/Operations/Maintenance of Gate Structures. It is worth noting that South Florida Water District

is now utilizing all stainless steel gates. Presented below are some of the advantages and disadvantages of

several different gate materials:


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ADVANTAGES

Stainless Steel Gates:

Stainless steel has excellent corrosion resistance.

Stainless steel gates would not need to be painted.

The maintenance cycle would be greatly increased.

The duration of the maintenance event would be reduced.

Potentially lighter gates.

Aluminum Gates:

Aluminum has excellent corrosion resistance.

Aluminum gates would not need to be painted.

The maintenance cycle would be greatly increased.

The duration of the maintenance event would be reduced.

Potentially lighter gates.

Concrete Gates:

Concrete does not have the same corrosion problems that steel has.

Concrete gates would not need to be maintained as often as steel gates.

Concrete can be designed to be impact resistant.

Lightweight concrete can be used in conjunction with normal weight concrete to lighten the overall

weight.

Compartments can be cast to increase buoyancy.

Left and right gates would use the same formwork.

DISADVANTAGES

Stainless Steel Gates:

Stainless steel has the same stiffness as structural steel.

Stainless steel is more difficult to weld than structural steel.

Stainless steel material costs much more than structural steel (about three times the cost on a per weight

basis).

Potential corrosion issues at connection points (hinge, pintle, drive mechanism).

Aluminum Gates:

Aluminum is only 33% as stiff as steel.


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Welded aluminum is about 66% the strength of steel.

Aluminum is difficult to weld.

Aluminum costs much more than structural steel (about two times the cost on a per weight basis).

Aluminum does not have an endurance limit, making fatigue a concern.

Potential increased corrosion of attached hardware (hinge, drive mechanism, pintle).

Concrete Gates:

Concrete can crack; cracks would eliminate water tight properties.

Replacement of individual members would be difficult.

Reinforcing steel may corrode under certain conditions (epoxy coated bars should be used).

Concrete structures are typically heavier than steel structures.

Attachment of hardware may present problems.

Spreader bar needed for lifting.

Required floor of gate structure may adversely affect operation problems caused by debris.

Longterm data on fiber reinforced plastic (FRP) reinforcing bars is only available for roughly ten years.

Lock and floodgates, constructed of steel, require maintenance to address issues that include corrosion

(rusting, pitting), seal deterioration, cracking, and impact damage. Each gate is unique in dimension and

weight to the lock or floodgate it serves. The maintenance cycle is usually about every 10 to 12 years;

however, this timeframe is often delayed by budgetary constraints, or accelerated by some form of impact

damage that makes a gate inoperable. For a lock, a complete maintenance event is usually done in two

consecutive years, where one set of gates will be pulled/rehabilitated at an optimal time of the year, then

repeated for the other set of gates the following year. A typical example of a maintenance cycle is the Port

Allen Lock where completion of the cycle would take about 90 days, but has been accelerated to 45 days

through the use of a spare set of gates. The length of closure of the lock has been about 6 to 9 days total to

facilitate maintenance. Depending on location, a maintenance cycle closure can impact users at a cost in

excess of $6 million (preHurricane Katrina). Tables 1 and 2 illustrate the economic impact to navigation

current (2004) maintenance cycles have at its most significant location, Calcasieu Lock, and where least effects

are encountered, Harvey Lock.


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Cost of 8 Day Closure at Calcasieu Lock and Harvey Lock

Calcasieu Lock Harvey Lock

Year 2001 Year 2001

Tons 38,680,000 Tons 2,094,000

8 Days of Avg Delay/Tow (hrs) 0.98

Tons 847,781

Algiers Lock

Cost of Waiting

Per Hr/Ton 0.08 Year 2001

Tons 22,879,000

Cost of 8 Day

Closure 6,510,957 Avg Delay/Tow (hrs) 3.37

(Use 4 Day Avg

or 96 hrs) Algiers Lock with Harvey Traffic 24,973,000

Estimated Avg Delay

per Tow if Harvey Traffic

diverts to Algiers Lock 7.13

Annual Cost of Delay Without Diversion 8,220,298

Annual Cost of Delay With Diversion 14,240,079

Incremental Annual Cost of Diversion 6,019,781

Incremental 8 Day Cost of Diversion 131,940

Table 1: Cost of 8Day Closure


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PRESENT WORTH OF ECONOMIC IMPACT OF MAJOR MAINTENANCE CLOSURES

@ CALCASIEU AND HARVEY LOCKS

Present

Worth Calcasieu Lock Harvey Lock

Factor $ 6,511,000 $ 132,000

Year @ 5.5% per maint. event per maint. event

10 0.585 $ 3,808,935 $ 77,220

11 0.555 $ 3,613,605 $ 73,260

20 0.343 $ 2,233,273 $ 45,276

21 0.325 $ 2,116,075 $ 42,900

30 0.201 $ 1,308,711 $ 26,532

31 0.19 $ 1,237,090 $ 25,080

40 0.118 $ 768,298 $ 15,576

41 0.112 $ 729,232 $ 14,784

Total: $ 15,815,219 $ 320,628

Present Worth of Impact to Navigation

Table 2: Present Worth of Navigational Benefits

Representatives from the USACE report that several significant components to maintenance exist. These

include pulling the gate, which requires a substantial number and/or capacity of cranes as each gate can weigh

from 30 to 200 tons, and sand blasting and painting, which comprise the greatest amount of

maintenance/restoration time. They further report that sector gates are more durable and exhibit less

structural deterioration than miter gates. These observations may be the reason that all currently proposed

new control structures are being planned or designed with sector gates.

The results of the 2004 VE Study may be summarized as follows:

The USACE New Orleans is currently very successful in operating and maintaining their gate and lock

structures. Current practices allow for virtually uninterrupted service for generally 10 years or more

between major maintenance cycles. However, the cost of performing major maintenance and more

importantly, the economic impact to navigation when critical structures are temporarily put out of service,

are significant. There is the potential that even marginal improvements may produce large benefits.

The 2004 VE Study produced a number of recommendations that appear to be economically justified.

Most require additional upfront investment cost that will lengthen the time between required major

maintenance events. Proposals address both changes that can be immediately implemented at relatively

low cost (add cathodic protection, change coating system) and changes to future gate design and material

selection (stainless steel, aluminum, concrete, etc.).

A number of the recommendations cite fieldproven design/maintenance practices that should have a high

level of confidence for successful implementation. Others suggest investigating something completely

new, and some degree of further research, development and analysis must be performed prior to fullscale

application.

Most of the recommendations are cost effective purely on the basis of potential direct maintenance cost

savings that may be realized by lengthening the time between required major maintenance events. It


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should be particularly noted that the potential economic benefits for improving maintenance cycle length

at locations where maximum marine traffic impacts occur are enormous. Maximizing major maintenance

cycles at these locations will be highly leveraged, justifying even very high first cost investment. For

example, the use of stainless steel gates appears to produce a benefit to cost ratio of over 5:1 if used in

lieu of regular structural steel at such a critical location. Please refer to the three Summary of Alternatives

tables on the following pages; but note that the costs shown are preHurricane Katrina estimates. The

overall benefit should still remain.

In considering the recommendations of the 2004 VE Report, USACE New Orleans should include such

factors as available funds, short and longterm implementation, and relative criticality of structure service

in further developing and prioritizing future maintenance actions.


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SUMMARY OF ALTERNATIVES

RANKED ACCORDING TO POTENTIAL LIFE CYCLE COST SAVINGS

NOT INCLUDING BENEFITS TO NAVIGATION (PREHURRICANE KATRINA)

Alternative

Number

Alternative Title

Total Estimated

Present Worth of

Life Cycle Cost

Savings Not

Including Impacts

to Navigation

SET 1 Changes to Maintenance

4 Use metal flamesprayed coating instead of paint $1,200,000

2 Use 100% solids coating for paint $600,000

1 Use galvanic anode cathodic protection in addition to paint $500,000

3A Apply ceramic or cementitious coating to steel  existing gates $200,000

6A Replace existing gates with stainless steel ($600,000)

SET 2 Alternative Materials and Design

8A Build sector gates out of concrete; pretension or posttension

concrete

$1,600,000

8B Build sector gates out of concrete; pretension or posttension

concrete, use FRP reinforcement instead of steel

$1,400,000

7 Build gates out of aluminum $1,100,000

9 Build FRP gates $300,000

5 Use tubular members where possible; eliminate/reduce complex

corners designing for corrosion resistance

$250,000

3B Apply ceramic or cementitious coating to steel  new gates $50,000

6B Build gates out of stainless steel ($125,000)

10 Build sector gates out of ultra high molecular weight polyethylene

(UHMWPE) plastic or cast/molded urethane or polyethylene, or

equivalent; with stainless steel wearing edges and corners

($4,000,000)


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Alternative

Number

Alternative Title

Total Estimated

Present Worth of

Life Cycle Cost

Savings Including

Minimum Impacts

to Navigation

SET 1 Changes to Maintenance

4 Use metal flamesprayed coating instead of paint $1,400,000

2 Use 100% solids coating for paint $800,000

1 Use galvanic anode cathodic protection in addition to paint $700,000

3A Apply ceramic or cementitious coating to steel  existing gates $250,000

6A Replace existing gates with stainless steel ($300,000)

SET 2 Alternative Materials and Design

8A Build sector gates out of concrete; pretension or posttension concrete $1,900,000

8B Build sector gates out of concrete; pretension or posttension

concrete, use FRP reinforcement instead of steel

$1,600,000

7 Build gates out of aluminum $1,300,000

9 Build FRP gates $600,000

5 Use tubular members where possible; eliminate/reduce complex

corners designing for corrosion resistance

$300,000

6B Build gates out of stainless steel $125,000

3B Apply ceramic or cementitious coating to steel  new gates $100,000

10 Build sector gates out of UHMWPE plastic or cast/molded urethane or

polyethylene, or equivalent; with stainless steel wearing edges and

corners

($3,600,000)


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Alternative

Number

Alternative Title

Total Estimated

Present Worth of

Life Cycle Cost

Savings Including

Maximum Impacts

to Navigation

SET 1 Changes to Maintenance

6A Replace existing gates with stainless steel $12,000,000

1 Use galvanic anode cathodic protection in addition to paint $11,100,000

4 Use metal flamesprayed coating instead of paint $11,100,000

2 Use 100% solids coating for paint $7,100,000

3A Apply ceramic or cementitious coating to steel  existing gates $3,000,000

SET 2 Alternative Materials and Design

8A Build sector gates out of concrete; pretension or posttension concrete $14,900,000

8B Build sector gates out of concrete; pretension or posttension

concrete, use FRP reinforcement instead of steel

$14,600,000

7 Build gates out of aluminum $13,500,000

9 Build FRP gates $12,800,000

6B Build gates out of stainless steel $12,400,000

10 Build sector gates out of UHMWPE plastic or cast/molded urethane or

polyethylene, or equivalent; with stainless steel wearing edges and

corners

$11,900,000

3B Apply ceramic or cementitious coating to steel  new gates $2,800,000

5 Use tubular members where possible; eliminate/reduce complex

corners designing for corrosion resistance

$1,900,000

The primary cost benefits arise when the impacts to commercial operations are taken into consideration.

Reduced downtime and improved corrosion resistance translates to considerable life cycle cost savings if

alternate materials and cathodic protection techniques are utilized to construct gates. It appears that concrete

gates offer the most promise in longterm cost savings. Significantly increased cycle time between

maintenance events coupled with reduced downtime for each maintenance activity translates into highly

improved reliability, maintainability, and navigational benefits.


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CONVEY ATCHAFALAYA RIVER WATER TO NORTHERN TERREBONNE MARSHES

A1 Address flow constrictions in the GIWW at Houma

There are two apparent flow constrictions in the GIWW at Houma: the Houma Tunnel and the Twin Span

(see location map below). These items will prevent desired proposed Atchafalaya River diversion flow from

going to the eastern Terrebonne Basin. The current planning rationale views this flow limitation as a planning

constraint given the belief that the tunnel cannot be removed (this also makes any possible flow improvement

to the Twin Span noneffective). It has been recently discovered, however, that LADOTD plans to build a high

rise bridge and take the tunnel out of service. See below excerpt from the TriParish news service in Houma:

The new high-rise bridge over the Intracoastal Waterway that will be built

to replace the Houma tunnel should be located where a railroad bridge now

crosses the waterway close to Bayou Black, audience members said at a

meeting last week in Houma.

The state Department of Transportation and Development formally kicked off

the project with the meeting, intended for Terrebonne residents to suggest a

variety of sites to build the bridge and to air their views on the project.

But the railroad bridge location near the south end of Dunn Street was the

only site that was brought up by audience members.

R. Gary McClure, an engineer with the Baton Rouge firm Shread-Kuyrkendall &

Associates who is studying the project, acknowledged that the railroad

bridge site was being considered, as did a DOTD official at the meeting. The

environmental impact of the new bridge would be minimal, according to

McClure.

The tunnel, completed in 1961, is currently having 10 pumps replaced at a

cost of $1.9 million and needs around $2 million worth of new lighting.

McClure and the DOTD official said the tunnel experiences frequent traffic

congestion.

State Sen. Reggie Dupre of Houma said the idea of replacing the tunnel has

been around since the late 1990s. He said the three tunnels existing in the

state - in Houma, Harvey and Belle Chasse - "are maintenance nightmares."

Once the replacement bridge is constructed, the tunnel can be removed. It may be necessary, however, to

accelerate this bridge project to accommodate the LCA schedule.

If the tunnel can indeed be removed, it would then appear to be practical to improve gravity flow across the

Twin Span and eliminate the entire GIWW flow constriction through Houma. This may be accomplished by

installing a channel section through the next bridge bent on the east side (see below map). An all earthen

channel with rock and/or steel sheetpile protection of the bridge foundation or an earthen channel in

combination with multiple concrete culverts under the bridge structure proper can create an adequate flow

section. This would, however, require the purchase of an estimated 15 to 20 developed residential properties

to the north and a partial vacant (industrial?) tract to the south. While politically undesirable, such real estate

purchase is possible and does not appear to be cost prohibitive.


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If only limited property can be obtained, an alternative would be to pump through the same bridge bent,

utilizing a pump station to the south and several large diameter forcemains discharging to the north. This

would be both a more expensive initial cost option as well as require significant future O&M cost.

A rough cost estimate for removing the tunnel, purchasing property, and installing a gravity conveyance

through the bridge is in the range of $7 to $12 million; removing the tunnel with a pumping option through the

bridge would be on the order of $20 to $35 million. Estimated cost of items as follows (design, management

and contingencies included):

Gravity Conveyance

Removal of tunnel $1$2 million

Real estate total acquisition costs $2 $4 million

Channel cut with culverts under bridge $4 $6 million

Total: $7 $12 million

Pumped Conveyance

Removal of tunnel $1$2 million

Real estate total acquisition costs $1 $3 million

Pump station (1,500 CFS) and forcemains $18 $30 million

Total: $20 $35 million

TWIN SPAN

BRIDGE

TUNNEL

EXISTING CHANNEL

CONSTRICTIONS OF

THE GIWW @ HOUMA


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ESTIMATED REQUIRED

PROPERTY PURCHASE

PROPOSED CHANNEL

WIDENING/CULVERT

PROPOSED CHANNEL

WIDENING OR CULVERT

UNDER TWIN SPAN

A2 Operate the Old River Control Structure to optimize flow split outside of the 70/30 mandate in non

flood conditions

The Old River connects the Red, Atchafalaya, and Mississippi Rivers. In the 1890s, the Atchafalaya River was

expanding and would have allowed the Mississippi River a shorter outlet to the Gulf of Mexico. By the 1950s,

it was apparent that Atchafalaya River could capture the entire Mississippi River flow. In 1954, Congress

authorized the USACE to construct the Old River Control Project to prevent the Mississippi River from changing

course. This legislation obligated the flow between the Mississippi River and the Atchafalaya River to remain

at its then current rate, a 70/30 split.

It appears possible that the Old River Control Structure has the capability to alter this flow split during low flow

conditions. During periods of low river flow, this 30% allocation may be less than needed in the Atchafalya

River to supply the desired quantity of freshwater flows into the GIWW. The ability to alter this flow ration

may be imperative to achieving the project goal of providing freshwater to the entire Terrebonne Basin when

it would be needed.

Such a change would require a change in federal law. The 70/30 split would be retained, unaltered, during

nonlow flow to avoid adverse affects. Over time, frequent and prolonged deviation from the 70/30 split at

low flow could possibly change the river bottom configuration enough to affect flood condition performance.

Further evaluation would therefore be required before this change in operation would be implemented.

Allowing flexibility to route more than 30% into the Atchafalya River would become an adaptive management

strategy to meet project salinity reduction purposes.

A3 Use City of Houma wastewater effluent to replenish cypress forests

A process recently utilized and planned in several localities is the use of secondary treated wastewater plant

effluent to feed newly planted cypress stands. Such a system accelerates tree growth and treats secondary

effluents to tertiary standards (as well as reduces effluent discharge to receiving waterways). This system is


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currently being considered for inclusion in the LCA program in the Missouri River Gulf Outlet (MRGO)

Ecosystem Restoration Project (St. Bernard Parish).

Passing effluent through natural or manmade vegetation has been shown to significantly improve the quality

of the effluent. This alternative measure would allow the effluent to flow over and through the vegetation in

the marshland, creating a filtering effect that would enhance water quality and add nutrients to the biotic

system.

The science addressing Contaminants of Emerging Concern is still in its infancy. Should such contaminants

(e.g., pharmaceuticals, byproducts of plastics and heavy metals) be present in the treated effluent, they may

be retained in the effluent; however, since this is not part of the drinking water supply, the issue may be

insignificant. In fact, by diverting the effluent to the marsh rather than to the river, improvements to the

drinking water supply in this respect may be improved.

It is not known what the current wastewater treatment system status is for the City of Houma (centralized

plant, numerous privately run package plants, etc.), but this may be a possible consideration if a target cypress

planting area (or existing stand) is relatively close to a wastewater treatment site(s). This can be a winwin

alternative that results in lower wastewater treatment costs and habitat creation/enhancement.

A4 Pump flow from Davis Pond Diversion from Company Canal

A possible means of delivering freshwater produced by the Davis Pond Diversion westward into Bayou

Lafourche (and indirectly into the Terrebonne Basin target area) may be by inducing westward flow in

Company Canal via pumping at the old lock location. This concept was developed in a previous VE Study 

Bayou Lafourche Siphon Restoration Project, July 2001; Proposal C1 (see Appendix C). Cost and hydraulic

considerations may limit this flow to less than 1,000 CFS but this may be a beneficial supplement to proposed

freshwater flow that may originate from the west (Atchafalaya River Diversion).

A5 Use Bayou Lafourche to convey freshwater to the northern Terrebonne marshes

In lieu of or complementary to conveying Atchafalaya River water to the northern Terrebonne marshes, this

proposal suggests transferring freshwater through Bayou Lafourche from the Mississippi River in the vicinity of

Donaldsonville approximately 55 miles to Company Canal, thus replacing the proposed transfer of freshwater

from the Atchafalaya River. Freshwater would be removed from the river by constructing a control structure.

Freshwater would also enter the GIWW further south of this location.

Bayou Lafourche, a former distributary of the Mississippi River, was closed for flood protection purposes in

1905. Bayou Lafourche had a channel capacity of approximately 11% of Mississippi River flows prior to

closure. Under the 1899 Rivers and Harbors Act, the USACE was ceded, i.e., acquired in perpetuity, flowage

easements for navigation purposes along this and other delta bayous. The sketch below shows a conceptual

control structure at the Mississippi River near its confluence with Bayou Lafourche to transfer 15,000 cubic

feet per second (CFS) down Bayou Lafourche to its confluence with the Company Canal.

A flow of perhaps as high as 15,000 CFS will inundate residential yards and docks, but not permanent

residences located along the top of the natural levee. Property owners would be compensated for dock and

yard structure replacement costs, but not property easements or rightsofway for their inundated land as

these privately owned parcels have encroached the navigational flowage easement held by the federal

government.


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In an effort to estimate a rough, orderofmagnitude cost for this proposal, the following assumptions are

made:

The bayou may support up to 15,000 CFS without channel modification (or less flow up to the amount

needed to support the unaltered restriction at Houma).

The transfer will require ~1,000 feet of four 12foot by 12foot buried culverts.

The following unit costs are assumed:

o Residential dock and yard structure replacement costs of $10,000/property, with an average

residential lot size along the Bayou of 200foot width

o Mississippi River control structure of $27 million

o Utility relocations and roadway work of $5 million

o GIWW shoreline improvements as proposed in the current design plan estimated at $10 million

o Culvert construction cost of $3,000 per linear foot for combined four culverts

o Engineering and Design allowing 15%

Contingencies allowing 40%.

Based on these assumptions, the approximate cost of this proposal is estimated in the $100 million range.


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A6 Construct miniWoodys Ditch east of Houma and west of Bayou Lafourche connecting the

Mississippi River to Lake Fields

This proposal suggests constructing a water transfer feature consisting of an openair canal plus, where

appropriate, buried culverts that will move freshwater from the Mississippi River in the vicinity of

Donaldsonville approximately 60 miles to Lake Fields, thus replacing the proposed transfer of freshwater from

the Atchafalaya River. This feature would parallel Bayou Lafourche on the south side and would run through

primarily agricultural land (to avoid marsh areas) at the back of the property avoiding as many structures as

possible. Freshwater would be removed from the river by constructing a control structure. Once the water

reaches Lake Fields, it can be distributed to desired areas primarily through existing canals, ditches, and bayous

that emanate from the lake. Water would then be allowed to enter the GIWW for distribution into the desired

project restoration areas. A suggested alignment is shown on the following map.

Idealized location of proposed miniWoodys Ditch

In an effort to estimate a very rough, orderofmagnitude cost for this proposal, the following assumptions are

made:

The feature will be ~60 miles long.

The feature will carry up to 15,000 CFS.

Approximately 90% will be open canal and 10% will consist of four 12foot by 12foot buried culverts.


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The cross section of the canal will be 10 feet deep with a 25foot bottom width, and 3 horizontal:1 vertical

side slopes.

25foot wide access roads will be provided on each side of the canal.

The following unit costs are assumed:

o Land acquisition and mitigation costs of $10,000/acre

o Mississippi River control structure of $30 million

o Utility relocations and roadway work of $25 million

o Canal construction cost of $7.50 per cubic yard

o Culvert construction cost of $3,000 per linear foot (for combined four culverts)

o Engineering and Design allowing 15%

o Contingencies allowing 40%

Based on these assumptions, the approximate cost of this proposal is estimated at $315 million.

A7 Ensure that local fishing interests are fully informed of project alternative impacts

The introduction of any significant freshwater into a currently brackish or saltwater regime will undoubtedly

change fish occurrence patterns in that area. There are probably thousands of sport and commercial

fisherman that utilize the project area inland waters. Saltwater fish are the prized catch and any major change

to water salinity will move these fish to other locations. It is therefore imperative that all sport and

commercial fishing interests are made fully aware of potential impacts and changes to fishing as a result of

project alternatives. This should go beyond the required public meeting forum. Failure to do so may result in

severe political backlash that could ultimately affect the success of this project.

A8 Require oil companies to plug canals connecting to GIWW

The Atchafalaya River Diversion Project proposes to raise the stage on GIWW sufficient to cause water to flow

toward the HNC. However, there are many points along the GIWW that will serve as diversion points for the

water, thus affecting a sort of line loss for the freshwater that is needed to the east of Houma. Many of

these diversion points result from where old and unused canals intersect the GIWW. The canals were built by

oil companies to access oil and gas deposits. The original concept proposes to plug these canals, thus limiting

the amount of line loss in the system. However, consideration should be given to requiring the oil and gas

companies that originally built the canals to plug them instead of using project costs. In addition, justification

under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) guidelines may

allow the taxing of the oil/gas industry to provide funds for backfilling of canals.

A9 Install nutria fencing along GIWW and birth control measures throughout project area

The proposed plan includes nutria (Myocastor corpus) control by trapping and hunting. Nutria cause plant

damage, erosion, land loss, and will interfere with vegetative recovery.


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Because nutria are not climbers, fencing will prevent access. A nutria fence consists of a mini floppy fence

constructed of 1inch mesh wire or plastic at least 2 feet high and staked so that it is wobbly. The fence should

not be pulled tight between the stakes, but rather have some give so that when the nutria tries to climb the

fence, it will wobble, discouraging further climbing. Constructing the fence so that it leans slightly toward the

nutrias side will increase its effectiveness. To prevent nutria from digging under the fence requires either 1) a

2foot wide wire apron on top of the ground on the animals side of the fence or 2) an apron buried 6 to 12

inches.

Birth control chemicals in sweet potatoes or carrots can be used to keep a nutria population under control.

The birth control program needs to assure that nontargeted mammals will not be affected. Such programs

have to be continuous because nutria that die without reproducing are replaced by others moving into the

vacant habitat due to fencing failure. For control in the Terrebonne barrier islands, consider placing a

continuous nutria fence along the north shore of each island. For the Atchafalaya to Terrebonne marshes,

consider placing a continuous fence along the GIWW and Bayou Lafourche or along the Morganza to the Gulf

levee. Vegetable bait would be delivered by air. Augmentation of the kill by hunting and trapping would be

beneficial.


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GENERAL/PLAN FORMULATION

G1 Develop Plan Strategies that account for much higher levels of GSL rise

The purpose of this ecological restoration is to achieve a sustainable solution, but the project must respond to

the combined rates of subsidence and GSL rise. GSL rise consists of two factors: 1) eustatic rise due to density

warming and 2) landbased glacial melt rise. Eustatic sea level rise during the next 50 years is expected to be

approximately 4 inches (IPCC 4th Assessment Report, 2007). The IPCC has not yet projected the portion of sea

level rise due to landbased glacial melt. Under the 2007 IPCC business as usual scenario, eustatic GSL is

projected to be 0.75 feet to 1.5 feet by 2100. At that time, no significant acceleration of GSL rise had been

detected. New research published this year indicates that GSL rise could be 3 to 4 feet by 2100, which is much

higher than IPCC 2007 predictions (Niels Bohr Institute, published in the journal Climate Dynamics). The great

uncertainty in the rate of GSL rise regards how quickly the ice sheets on land will melt.

The subsidence rate in the Mississippi River delta planning area ranges from 1 to 3.5 feet by 2100. The relative

sea level rise (i.e., the eustatic portion only of GSL rise and the deltas subsidence rates) used for the LACPR for

the next 50 years are 1.3 to 2.6 feet, or 2.6 to 5.2 feet by the end of the century.

Twentieth century rise in sea level from observed data was about 1.8 mm/year as result of longterm response

to the end of the last ice age. Since 1992, however, satellite data have recorded an accelerated rate of GSL rise

of 3.0 mm/year, but this is not sufficiently long to determine if this rate will be prolonged or is a shortterm

change.

Project benefits depend upon habitats maintained above sea level. Consequently, benefits beyond the 50year

planning horizon will be lost due to subsidence, GSL rise, and storminduced habitat loss. Longterm melting of

the Greenland ice sheet during subsequent centuries of warming could result in complete melting over several

thousand years, eventually resulting in a GSL rise of 22 feet (7 meters).

As the rate of GSL rise in the future is unknown, the project should develop specific Plan Strategies that

consider the range of possible future GSL rates, and check to see how sensitive the project design is to those

different scenarios. Those future scenarios include:

1. A low level that is based on an extrapolation of the historic rate assumes GSL rise will be linear in the

future and will not accelerate.

2. A medium level that assumes GSL rise of 0.5 meters by 2100.

3. A high level that assumes a greater future acceleration of GSL rise of 1.5 meters by 2100.

However, as noted above, current science projecting an accelerated rate of landbased glacial melt has huge

ramifications for project viability or perpetual cost obligations. Future GSL rise rate based on this science must

wait on future work by the IPCC and U.S. agencies to be completed by late 2009. This work is based on recent,

and increased, rates of observed GSL rise using satellite data, previous historic rates of sea level rise during

past glacial melt. Currently, work is underway by the USACE, National Oceanic and Atmospheric

Administration (NOAA), and USGS to investigate the glacial melt contribution to future GSL.


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G2 Develop a Seasonal Freshwater Management Plan

Wetlands in the project area are deteriorating as a result of subsidence, lack of sediment and nutrient

deposition, saltwater intrusion and erosion. Deterioration will continue unless action is taken to resolve the

causative factors. Sustainable protection and enhancement of the wetlands in the project area is dependent

on providing a hydrologic regime that minimizes the physiological stress to wetland vegetation.

Seasonal differences in the need for freshwater and nutrients, and the locations from which freshwater can be

recruited and distributed, should be optimized. For example, the quantity of water that can be diverted from

the Atchafalaya River to the GIWW is somewhat limited due to infrastructure restrictions: traffic tunnel in

Houma and the Houma twin bridge abutments are two examples. Freshwater could also be diverted into the

GIWW system at the Harvey Lock and Algiers Lock. In addition, freshwater is being diverted into Bayou

Lafourche and Davis Pond. Each of these is an individual site at which important resources can be introduced

into the wetlands; however, quality and quantity of freshwater could be enhanced with coordination and

planning treating these sources as a supply network.

Opportunities exist to naturalize the distribution of freshwater and, to a limited extent, the deltaic forming

sediments, improve distribution of freshwater, and to reduce the negative impacts of Gulf storm events.

Seasonal Gulf events have an intensive impact on the remaining marsh areas. Opportunities exist through

freshwater supply and distribution to create a healthier marsh which will be more resistant to the normal

range of events.

Cost to develop a management plan is minimal. Implementing the management plan would likely require

instrumentation and communication equipment.

G3 Create federal advisory committee

Public participation will be achieved through the NEPA process involving federal and state cooperating

agencies, public review, and public and legislative hearings. This can be augmented by developing a formal

multistate committee. A federal advisory committee can be comprised of both government and non

governmental stakeholders along the Mississippi flyway, including Canada. The Federal Advisory Committee

Act (FACA, PL 42463) governs the establishment and behavior of federal advisory committees. There are now

approximately 1,000 such committees. FACA was an attempt by Congress to curtail the "lockerroom

discussion" that had become prevalent in administrative decisions and obligates transparency in the process.

For example, a federal advisory committee may include the Missouri and Mississippi State River Basin

Commissions, and national and Canadian environmental organizations. This would expand national interests to

support Congressional intent, but will add additional administrative burden to the USACE.

Example FACA Committee: The National Park Service, Georgia, Big Cypress National Preserve OffRoad Vehicle

(ORV) Advisory Committee.


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G4 Identify and incorporate the effects of subsidence from fluid withdrawal in the project analysis and

design; utilize water injection to minimize the impacts of fluid withdrawalinduced subsidence

The Principal of Effective Stress is a well known geotechnical engineering principal applied to the consolidation

of sediments and rock when there is a net change in interstitial pressure in the system. Principally, this can be

described as an increase in stress between particles resulting from a reduction of pore fluid pressure that

causes the solid particles in the mass to move closer together. Once this consolidation of mass occurs, it

cannot be reversed. The reduction in fluid pressure happens when the fluids are permanently removed from

the system (that is, through the pumping or mining of groundwater, oil, and gas). The consolidation of the

solids produces general settlement (or subsidence) of the ground surface.

Significant ground surface subsidence (sometime associated with fault development) as a direct result of fluid

withdrawal has been documented worldwide. Well known cases exist in Houston, south central Arizona, North

Las Vegas, and central California. In the Long Beach, California area, from about 1920 to 1960, 29 feet of

surface subsidence occurred that was directly related to the removal of oil and gas.

The current documents do not fully address timedependent subsidence in the project area due to oil and gas

withdrawal, a process which is ongoing in the area. The amount of such subsidence has not reportedly been

documented to date. It is recommended that surface subsidence due to fluid withdrawal in the project area,

and its future impacts on project sustainability, be assessed and included in the project design and documents.

There may be some visual evidence of a correlation of open water in the project area with the concentrated

location of oil wells. It could be interpreted that some of this open water resulted, in part, from subsidence

associated with the withdrawal of oil and gas from these concentrated well areas. This visual comparison can

be seen in the two maps below.


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As was mentioned above, from about 1920 to 1960 in the Long Beach, California area, 29 feet of surface

subsidence occurred that was directly related to the removal of oil and gas. Once this problem was identified,

the petroleum industry elected to inject saltwater into the subsurface to replace the withdrawn oil and gas as

a mechanism of recharge that would maintain the internal pressures, thus minimizing the change in effective

stress. As a result of this effort, additional subsidence has been limited to about 1 foot to date.

An added benefit of saltwater recharge has been the ability to increase the extraction of petroleum from the

reserve. Such recharge has become a standard practice in the industry. If this is not already being done within

the project area, the USACE is encouraged to open discussions with the oil industry to see if the technique can

be implemented. This would reduce the amount of future subsidence due to fluid withdrawal, extending the

life of the project and its sustainability.

G5 Consider alternate procurement methods for construction

Given the complexities associated with identifying sources of material for renourishment of the barrier islands,

transport and placement of the material, and preservation of the material, as well as limited specialized

contractor availability, use of alternate procurement methods should be considered. Examples of some of

these methods include CMatRisk and using Habitat Units as the pay items.

CMatRisk procurement, also known as Integrated DesignBidBuild or Earlier Contractor Involvement,

involves selecting a contractor and separate designer during the design phase. Both parties work together

under separate contracts with the government with the objective of developing a design that is most efficient.

The government then negotiates and awards construction packages to the contractor. If negotiations are not

successful, the government reserves the option to bid the work on the construction open market.


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The process calls for the selection of a construction contractor (based on qualifications only) early in the design

phase. This contractor and the designer collaborate in developing a design most suitable for the specific

contractor while meeting all performance requirements (such as maximizing the number of Habitat Units

created). In this arrangement, the government has the option to either negotiate a subsequent construction

price with the previously selected contractor or bid the job on the open market. Such a procurement plan

would help assure a constructible design that meets the relatively complex requirements of this project.


PROJECT ANALYSIS


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PROJECT ANALYSIS FINAL REPORT

SUMMARY OF ANALYSIS

The following value analysis tools were used to study the project:

Key Project Factors

Function Analysis / FAST Diagram


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KEY PROJECT FACTORS

The first day of the study included meetings with the project stakeholders. The following summarizes key

project issues and concerns identified during these sessions.

PROJECT ISSUES

The following are some of the issues and concerns associated with the Terrebonne Basin Barrier Shoreline

Restoration Project:

Lack of sediment for barrier island renourishment. The demand for sediment from various projects

exceeds the supply at Ship Shoal.

Project authorization requires signed Chiefs Report by December 2010.

There is a limit to the number of dredges available to the project to supply sediment for barrier island

renourishment.

Absolute sea level rise threatens the projects justification and sustainment.

Key navigation routes through the project limits must be maintained.

Project funds do not provide for future renourishment requirements.

The following are some of the issues and concerns associated with the Convey Atchafalaya River Water to

Northern Terrebonne Marshes Project:

Project authorization requires signed Chiefs Report by December 2010.

Existing tunnel and Twin Span bridge in Houma creates restriction to GIWW flow rates (maximum 2,600

CFS).

The availability of water during low flow times may limit the amount of freshwater needed to counteract

salinity levels.

Flow between the Mississippi River and the Atchafalaya River is legislated to remain at a 70/30 split.

Project raises the 100year flood plain along the GIWW.

Project lacks hydrology and hydraulics data to determine necessary flows from Atchafalaya River to HNC

and impacts to existing systems.

Multiple private land owners present issue for gaining permissions for accessing project sites.


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Analysis  3.3

FUNCTION ANALYSIS / FAST DIAGRAM

Function analysis was performed and a FAST Diagram was produced, which revealed the key functional

relationships for the project. This analysis provided a greater understanding of the total project and how the

project objectives and specific project activities are related.


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Analysis  3.4

Scope

Line

Terrebonne Bay Shoreline, Atchafalaya River

Diversion, Houma Gate Operations

HOW? FAST DIAGRAM WHY?

Manage

Salinity

All Time

Functions

Scope

Line

Add

Nutrient

Add

Sediment

Improve

Water

Quality

Prevent Loss

Restore/

Protect

Habitat

Dissipate

Wave

Energy

Re-Nourish

System

Reduce

Erosion

Reduce

Storm

Damage

Create Land

Divert

Fresh

Water

Redirect

Flow

Transport

Material

Place

Dredge

Material (at

Islands)

Detail

Activities

Place Rock

Preserve

Environment

Protect

Infrastructure

Maintain

Navigation

Install

Vegetation

Build

Diversion

Gates

Restore

Land

Forms

Restore

Beaches

Restore

Dunes

Backfill

Canals

Manage

Tidal Forces

Construct

Diversion

Channels

Add

Sediment

Place

Dredge

Material

(Feeder

Location)

Restore

BackMarsh

Promote

Fresh

Wetlands

Prevent Salt

Wetlands

Minimize

Land Loss

Pipe Dredge

Material

Manage

Salinity

Control

Intrusion

Block

Flows

Block

Surge

Houma Lock

Atchafalaya

Diversion

Terrebonne

Bay Shoreline


PROJECT INFORMATION


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Information  4.1

PROJECT INFORMATION

INTRODUCTION

The program goal of the coastwide LCA Ecosystem Restoration Plan is to reverse the current trend of

degradation of the coastal Louisiana ecosystem by maximizing the use of restoration strategies to reintroduce

historic flows of water, nutrients, and sediment to coastal wetlands, and to maintain the structural integrity of

the coastal ecosystem.

PROJECT BACKGROUND

Title VII of the Water Resources Development Act (WRDA) of 2007 authorizes the LCA program. The authority

includes requirements for comprehensive coastal restoration planning, program governance, project

modification investigations, a Science and Technology (S&T) program, restoration project construction, a

program for beneficial use of dredged material, feasibility studies for restoration plan components, and other

program elements.

Specifically, Section 7006(e)(3) requires the Secretary of the Army to submit one feasibility report to Congress

on six elements by December 31, 2008 and a Chiefs Report by December 31, 2010. The six elements are:

1. Multipurpose Operation of Houma Navigation Lock

2. Terrebonne Basin Barrier Shoreline Restoration

3. Convey Atchafalaya River Water to Northern Terrebonne Marshes

4. Small Diversion at Convent/Blind River

5. Amite River Diversion Canal Modification

6. Medium Diversion at White Ditch

This study focused on the first three elements.

PROJECT DESCRIPTIONS

Terrebonne Basin Barrier Shoreline Restoration

The natural processes of subsidence, habitat switching, and erosion, combined with human activities, have

caused significant adverse impacts to the Northern Terrebonne Marshes, including accelerated wetland loss

and ecosystem degradation.

The project proposes to reverse the continuing degradation and deterioration of the Isles Dernieres (Raccoon

Island, Whiskey Island, Trinity Island, East Island, and Wine Island) and Timbalier Islands (Timbalier Island and

East Timbalier Island) to achieve a sustainable coastal ecosystem that can support and protect the

environment, economy, and culture of southern Louisiana and thus the nation.


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Information  4.2

Project objectives include:

Prevent habitat conversion and future land loss where predicted to occur.

Protect vital socioeconomic resources, including cultures, community, infrastructure, business and

industry, and flood protection.

Restore and maintain characteristics of natural marsh hydrology.

Reduce salinity levels in project area.

Increase sediment and nutrient load to surrounding wetlands.

Increase residence time of freshwater.

Sustain existing fish and wildlife habitat.

Management measures were developed to address study area problems and to capitalize upon study area

opportunities. Management measures were derived from a variety of sources, including prior studies, the

Conceptual Ecological Model, the NEPA public scoping process, and the multidisciplinary, interagency PDT.

Alternative Plan Strategies will be used to identify combinations of management measures to achieve the

outputs represented by each strategy. The strategies were identified and developed to produce a full

spectrum of alternative plans as required by NEPA and USACE planning guidance in ER 11052100. Alternative

Plan Strategies are designed to be significantly different from one another and to represent the entire range of

solutions to identified problems within the study area.

The management measures evaluated can be grouped into the following two categories:

Hard Structural

Breakwaters

Groins

Terminal groins

Sand fencing

Barges/Ships

Sheet pile

Pass closures

Canal plugs

NonStructural

Dune restoration

Marsh creation

Beach restoration

Beach nourishment

Subtidal sediment placement

Addition of sediment into nearshore environment to supplement

littoral drift

Beach closure

Small marsh island construction on bayside for bird habitat

Vegetative planting

Herbivory control

Biological bioengineered oyster reefs

Spit creation

Canal backfilling


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Information  4.3

The initial array of alternative Plan Strategies developed by the PDT includes:

Plan Strategy A: No Action

Plan Strategy D: Maintain island geomorphology and ecological function

Plan Strategy E: Increase of current configuration and functional geomorphology

Plan Strategy F: Maximize the allocated and available resources for the barrier island restoration

Two Plan Strategies (B and C) were eliminated from further study prior to the VE Study.

A signed Chiefs Report is due to congress by December 31, 2010. Authorized costs for the project from WRDA

of 2007 (Public Law 110114) are $124,600,000.

Multipurpose Operation of Houma Navigation Lock

A lock complex is proposed to be constructed in the HNC as part of the Morganza, Louisiana to the Gulf of

Mexico Hurricane Protection Project to provide flood protection, drainage, environmental benefits (i.e.,

salinity control), and navigational passage. The HNC Lock would be located in Dulac, Louisiana near the

confluence of the HNC and Bayou Grand Caillou. The lock complex will consist of a 250foot wide floodgate, a

110foot wide by 800foot long lock chamber, and the associated necessary improvements to the site, all built

in a realigned channel just west of the existing HNC. The 250foot wide floodgate is designed to allow for

continued use of the channel by the offshore fabrication industry located in Houma, 20 miles to the north.

The HNC Lock Complex, including the large floodgate, will be operated under tidal flow and salinity conditions

and possibly to retain upstream freshwater.

Convey Atchafalaya River Water to Northern Terrebonne Marshes

The purpose of the proposed action is to reverse the current trend of degradation of the Terrebonne marshes

resulting from subsidence, erosion, saltwater intrusion, and lack of sediment and nutrient deposition. The

project proposes to accomplish this by utilizing freshwater, sediments, and nutrients from the Atchafalaya

River and the GIWW.

The project study area comprises approximately 1,000 square miles (660,000 acres) in southern Louisiana in

the vicinity of the City of Houma and Terrebonne Parish. The study area is bound to the west by the Lower

Atchafalaya River, to the east by the Bayou Lafourche ridge, to the north by the Bayou Black ridge, from the

Lower Atchafalaya River Water to the City of Houma, and by the GIWW, from the City of Houma to the Bayou

Lafourche ridge. The southern boundary of the project lies along what would have historically been the

transitional area from fresh to brackish marsh. Due to the magnitude of the 1,026 square mile project area,

the entire project area was divided into three subunits labeled as West Bayou Penchant Area, Central Lake

Boudreaux Area, and East Grand Bayou Area.

The objective of the project is to provide additional freshwater, nutrients, and fine sediment to the area. The

introduction of additional freshwater could facilitate organic sediment deposition, improve biological

productivity, and prevent further deterioration of the marshes. Specific project objectives include, but are not

limited to the following:


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Information  4.4

Prevent, reduce, and/or reverse future wetland loss.

Protect vital socioeconomic resources, including cultures, community, infrastructure, business and

industry, and flood protection.

Achieve and maintain characteristics of sustainable marsh hydrology.

Reduce salinity levels in project area.

Increase sediment and nutrient load to surrounding wetlands.

Increase residence time of freshwater.

Sustain productive fish and wildlife habitat.

The study is currently considering the following alternative Strategic Plan concepts as part of the initial array:

1. ARTM 1: No Action. Alternatives developed under this strategy will include no measures from this project.

The future condition will include sea level rise, subsidence, and other projects that are under construction

or are likely to be constructed.

2. ARTM 2: Utilize Existing Flow and Management Measures to Maximize Restoration Efforts. Alternatives

developed under this strategy will focus on modifying the interior portions of the project area. They will

not actively attempt to introduce additional freshwater carrying sediments and nutrients from other

sources.

3. ARTM 3: Utilize Increased Flow from the Atchafalaya River and Management Measures to Maximize

Restoration Efforts. Alternatives developed under this strategy will focus on increasing supply from the

Atchafalaya River to introduce additional freshwater carrying sediments and nutrients. Preliminarily, the

focus of introducing additional flow from the Atchafalaya River consists of implementing an opening

through Avoca Island to increase flow into the GIWW.

4. ARTM 4: Utilize Increased Flow from Locations East of the Project Area and Management Measures to

Maximize Restoration Efforts. Alternatives developed under this strategy will focus on attempting to draw

water from outside the project area to the east along with modifying the interior portions of the project

area. Preliminarily, the focus of introducing additional flow from locations east of the project area consist

of diverting additional flow from Davis Pond.

5. ARTM 5: Utilize Increased Flow from the Atchafalaya River and Locations East of the Project Area and

Management Measures to Maximize Restoration Efforts. Alternatives developed under this strategy will

focus on maximizing flow inputs from both the Atchafalaya River and locations east of the project area

along with modifying the interior portions of the project area.

INFORMATION PROVIDED TO THE VE TEAM

The following projectrelated information was provided to the VE team for their use during the study:

Terrebonne Basin Barrier Shoreline Restoration, Louisiana Coastal Area, Feasibility Scoping Report, dated

April 2009


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Project Information  4.5

Convey Atchafalaya River Water To Northern Terrebonne Marshes (Artm), Louisiana Coastal Area,

Feasibility Scoping Meeting Report, dated April 2009

Coastal Impact Assistance Program Application, Houma Navigation Canal Lock, dated May 22, 2006

Value Engineering Study Report, Houma Navigation Canal Lock, dated January 2001


IDEA EVALUATION


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Idea Evaluation 5.1

IDEA EVALUATION

INTRODUCTION

All of the ideas generated by the VE team were recorded and evaluated with projectspecific attributes applied

to each idea to ensure an objective evaluation.

PERFORMANCE ATTRIBUTES

Performance attributes represent those aspects of a projects scope and schedule that may possess a range of

potential values (as opposed to performance requirements which represent essential, nondiscretionary

aspects). The VE team developed the following list of performance attributes to act as criteria for considering

the value potential of the creative ideas:

Terrebonne Performance Attributes

Coordination with natural/coastal processes

Includes sustainability of barrier island system

Functionality of habitat

Includes acres of habitat and quality of habitat

Degree of protection to interior marsh

Schedule

Houma Lock Performance Measures

Impacts to navigation

Ability to control salinity

Maintainability

Atchafalaya Performance Measures

Impacts to water quality

Impacts to existing infrastructure

Maintainability

Impacts to navigation

Coordination with other projects

Schedule

Flood control reliability during high water event

Construction impacts (including minimizing impacts to navigational operations or downtime)


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Idea Evaluation 5.2

EVALUATION PROCESS

The VE team, as a group, generated and evaluated ideas on how to best perform the various major

components or functions of the project. The goal of the evaluation was to select the best ideas that would

produce a high level of performance at an acceptable level of cost. The evaluation used the key criteria listed

above and the function analysis performed by the VE team.

Given the relatively early level of project development at the time of the VE Study (i.e., no original design), the

team evaluated each of the ideas with respect to each of the key evaluative criteria to determine whether it

was better than, equal to, or worse than the other feasible alternatives. The team then reached a consensus

on the ideas development status.

Readers are encouraged to reconsider all ideas generated by the VE team, as previously rejected ideas may

prove to be feasible as the project development proceeds beyond the scope of the VE Study.

IDEA EVALUATION

All of the ideas that were generated during the creative phase were recorded and each idea was discussed

individually and the advantages and disadvantages of each were discussed.

The Idea Evaluation Summary Table containing all of the ideas, and the rating applied to each idea, is

presented on the following pages. The ideas were assigned a recommendation for development as follows:

Develop = Develop into VE Alternative Concept

ABD = Being Done or Part of Original Scope

Eliminate = Idea Rejected or Outside Project Scope

Comb w/ No. = Idea Combined with Another Idea


IDEA EVALUATION

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Idea Evaluation 5.3

No. Idea Description Development

Status

Houma Lock and Gate

H1 Eliminate Houma Lock Develop

H2 Close Houma floodgate and lock traffic all the time Comb w/ H1

H3 Optimize holistic system to consider HNC flow rate and need/operation of

lock

Comb w/ H1

H4 Optimize improvement of Houma GIWW restriction with need/operation of

lock

Eliminate

H5 Divert water through Houma constriction (Twin Span bridge) Comb w/ A2

H6 Eliminate restriction at Houma by replacing tunnel Develop

H7 Budget for maximum lock operation Comb w/ H2

H8 Consider extended utilization of temporary barge gate Develop

H9 Relocate Gulf Island Fabrication out of Houma to eliminate gate Eliminate

H10 Consider dawn and dusk lockthrough for continuous lock operation Comb w/ H2

H11 Consider Gulf Island Fabrication traffic to be westonly and eliminate gate Eliminate

H12 Consider Gulf Island Fabrication traffic by road to Port of New Orleans Eliminate

H13 Increase lock length to 1,200 feet for continuous operation Comb w/ H2

H14 Construct 250foot lock and construct closure dam on HNC in lieu of gate

(accounts for high sea level rise)

Develop

H15 Use a barge gate for floodgate Develop

H16 Construct concrete sector gates or other maintenancefavorable materials Develop

H17 Use air curtain to block saltwater intrusion in lieu of gate Eliminate

H18 Implement adaptive management plan for Houma Lock Comb w/ H2

H19 Install wicker gates on HNC cuts into marsh Develop

H20 Perform parametric analysis of project alternatives accounting for sea level

rise

Comb w/ G5

H21 Install adjustable sill to block saltwater wedge Eliminate

H22 Defer construction of 200foot gate and use localsponsored barge gate Comb w/ H8

H23 Install a salinity monitoring system on HNC to automatically close gate Develop

H24 Canal around bridge over GIWW to introduce more water to HNC Comb w/ 5

Atchafalaya River Diversion

A1 Pump around Houma restriction Comb w/ H5

A2 Address flow constrictions in the GIWW at Houma Develop

A3 Eliminate Houma restriction by constructing bridge and demolishing tunnel Comb w/ H6

A4 Increase GIWW capacity at Houma restriction by exposing bridge abutments Eliminate

A5 Install permanent dredge plants at Atchafalaya Bar channel for sediment for

marsh building

Eliminate


IDEA EVALUATION

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Idea Evaluation 5.4

No. Idea Description Development

Status

A6 Alter Old River Control Structure to divert additional water to Atchafalaya

River as needed (70/30 congressional mandate)

Develop

A7 Construct drawbridge in lieu of permanent bridge for tunnel replacement ABD

A8 Include pipeline to provide sediment to marsh areas ABD

A9 Assess impacts of altering ORCS flow ratio on Mississippi, Atchafalaya, Old,

and Red Rivers

Comb w/ A6

A10 Pump Davis Pond flow from Company Canal Develop

A11 Construct miniWoodys Ditch east of Houma and west of Bayou Lafourche Develop

A12 Raise elevation of canal south of Lake Salvador to induce flow westward Eliminate

A13 Incorporate effects of subsidence from fluid withdrawal into project analysis Comb w/ G6

A14 Introduce saltwater reinjection to limit impacts of fluid withdrawal Comb w/ G6

A15 Incorporate latest sea level rise data into project analysis Comb w/ G5

A16 Require oil companies to plug canals connecting to GIWW Develop

A17 Expand CERCLA to tax oil/gas industry to provide funds for backfilling of

canals

Comb w/ A16

A18 Increase federal excise tax on gas to provide funds for ecological

rehabilitation projects

Eliminate

A19 Exercise federal floodway rights in Bayou Lafourche Develop

A20 Deepen GIWW in lieu of raising water elevation Eliminate

A21 Convert brackish marshes to saltwater marsh Eliminate

A22 Ensure local fisheries are informed of project impacts Develop

A23 Limit study area to levee line of Morganza Levee Project Eliminate

A24 Use City of Houma wastewater effluent to replenish cypress forests Develop

A25 Install nutria fencing along GIWW and birth control measures throughout

project area

Develop

A26 Use Algiers and Harvey Lock as source for freshwater to HNC Develop

A27 Construct channel diversion south of Houma to connect to GIWW to the east Develop

Terrebonne Basin Barrier Shoreline Restoration

T1 Install inverted breakwaters and use fill for replenishing backmarsh Develop

T2 Calculate renourishment rates required to sustain barrier islands accounting

for absolute sea level rise

Develop

T3 Use a given planning horizon (i.e., 50year) for renourishment requirements

based on a range of sea level rise

Comb w/ T2

T4 Obtain a clear definition of the sustainability project objective Develop

T5 Include renourishment costs in project costs Develop

T6 Establish federal trust fund for renourishment costs Develop

T7 Construct new barrier island chain closer to new shoreline Develop


IDEA EVALUATION

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Idea Evaluation 5.5

No. Idea Description Development

Status

T8 Relocate Timbalier Islands to the north using existing islands as sediment

source

Eliminate

T9 Incorporate a hard core into barrier islands Comb w/ T10

T10 Fix barrier islands in current location; Harden islands to reduce rate of roll

over

Develop

T11 Divert Mississippi River to provide sediment for littoral drift (Feed the

Beast)

ABD

T12 Prioritize which barrier islands should be saved ABD

T13 Use East Timbalier as a feeder island for other islands Eliminate

T14 Utilize sand recycling/backpassing for barrier island renourishment Develop

T15 Allow revetments Comb w/ T10

T16 Use buried revetments Comb w/ T10

T17 Use Geotubes for dune core Comb w/ T10

T18 Utilize concrete armor units in lieu of rock Comb w/ T10

T19 Procure environmental dredging fleet Develop

T20 Use Crock for barrier island hardening and relocate as necessary to allow roll

over

Eliminate

T21 Evaluate a retreating strategy for relocating barrier islands closer to marshes Comb w/ 7

T22 Utilize congressional action to allocate Ship Shoal sands Eliminate

T23 Evaluate actual quantities of available sediment at Ship Shoal and determine

appropriate locations

Comb w/ T42

T24 Design alternatives for future tidal prism ABD

T25 Close Wine Island Pass; connect East Island to Wine Island Eliminate

T26 Construct east end of each island wider than west end to act as sediment

source; ensure islands have sufficient aspect ratio for coastal geomorphic

processes

Develop

T27 Change the term nonstructural in project documents to soft structural Develop

T28 Utilize water injection to minimize impacts from fluid withdrawalinduced

subsidence

Comb w/ G6

T29 Connect the two pieces of East Timbalier Island and close the pass in

between

Eliminate

T30 Prioritize project components based on habitat loss factors Develop

T31 Investigate additional Mississippi River diversions to provide sediment for

barrier islands

ABD

T32 Implement oil/gas industry outreach program regarding future sediment

management practices

Develop


IDEA EVALUATION

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Idea Evaluation 5.6

No. Idea Description Development

Status

T33 Conduct offshore sediment analysis to identify alternative sources of barrier

island renourishment sediment; provide MMS sufficient funds to map

sediment sources

Develop

T34 Consider variable habitat types on barrier islands ABD

T35 Construct permanent pipeline from Ship Shoal to the east end of Timbalier

Island

Develop

T36 Consider alternate procurement methods for construction Develop

T37 Construct groins and/or breakwaters with prefilled sediment Develop

T38 Run dredges using green technologies in lieu of diesel Comb w/ T35

T39 Add Plan Strategy that addresses habitat needs in excess of budgetary

limitations

Develop

T40 Develop Plan Strategies to evaluate differing renourishment requirements

and island hardening alternatives

ABD

T41 Use birth control agents to control nutria Comb w/ A25

T42 Use MMS to regulate Ship Shoal quantities to various projects needing

sediment

Develop

T43 Relocate pipelines crossing Ship Shoal to increase sediment capacities

available

Eliminate

T44 Use abandoned pipelines at Ship Shoal for sediment transport Eliminate

T45 Utilize backbay material for renourishment of barrier islands Eliminate

General/Plan Formulation

G1 Use upwelling ram pumps to bring cold water to ocean surface to reduce

hurricane intensities

Eliminate

G2 Use ram pumps to power sediment transport piping Eliminate

G3 Develop a seasonal freshwater management plan Develop

G4 Create federal advisory committee to represent the migratory bird interests

(FACA)

Develop

G5 Perform parametric analysis of project alternatives accounting for the three

levels of sea level rise

Develop

G6 Identify and incorporate effects of subsidence from fluid withdrawal into

project analysis

Develop


VE TEAM AND PROCESS


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes VE Team and Process 6.1

VE TEAM AND PROCESS

The SAVE International VE Job Plan was followed to analyze the criteria/functions of the project and the issues

of concern, create and evaluate ideas for change, and develop and present alternatives to the project team

and stakeholders.

VE TEAM AND PROCESS

This fourday VE Study was performed during the period of May 5  8, 2009. The study was facilitated by Mark

Watson, a Professional Engineer and Certified Value Specialist with Value Management Strategies, Inc. The VE

team members and key project contacts are listed below.

The VE Team included:

David Cannon Everest International Consultants Coastal Engineer

Ron Tanenbaum Value Management Strategies, Inc. Geotechnical Engineer

Frank Vicidomina USACENew Orleans District CoVE Team Leader

Wes Wilson Environmental Protection Agency Environmental Engineer

Chester Watson Biedenharn Group, LLC Hydraulics Engineer

Mark Watson Value Management Strategies, Inc. VE Team Leader

A complete list of all study participants is documented on the subsequent pages at the end of this section

The SAVE International VE Job Plan was followed to analyze the criteria/functions of the project and the issues

of concern, create and evaluate ideas for change, and develop and present alternatives to the project team

and stakeholders.

Value Engineering is a strictly adhered to process that follows specific steps and procedures. The specific steps

in the VE process are as follows:

Step 1: Preparation  Developing a basic understanding of the clients/users needs and requirements,

specific goals, and current costs, with an agreement on the scope of the study.

Step 2: Information  Which is gathered prior to and during the study, and is reviewed and discussed

with the team. A summary of project constraints, critical issues, and observations from field inspection

can be found in the Project Analysis section.

Step 3: Function Analysis  Defines the functions of the project through an organized use of the

Function Analysis System Technique (FAST) diagram that shows how the functions are related to one

another. One FAST diagram was developed for this study and is shown in the Project Analysis section.

Step 4: Speculation  Also known as creativity, it is the application of brainstorming techniques to

develop a large quantity of ideas rather than focusing on the quality of ideas. A complete list of

workshop ideas can be found in the Idea Evaluation section.


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes VE Team and Process 6.2

Step 5: Evaluation  Reduces the large quantity of ideas to a few high quality ideas.

Step 6: Development  The concepts identified in the evaluation phase are developed into specific VE

alternatives that have been technically validated and quantified as much as possible.

Step 7: Report  Containing the VE teams recommendations and a presentation to the project

stakeholders to receive their approval of these recommendations.

Step 8: Implement and Audit  Tracking the implementation of alternatives and auditing the results

measures the effectiveness of the VE effort.


Mark Watson Value Management Strategies, Inc. VE Team Leader (816) 2060067 mark@vmsinc.com

Ron Tanenbaum Value Management Strategies, Inc. Geotechnical Engineer (858) 2047942 rtanenbaum@sbcglobal.net

Frank Vicidomina USACENew Orleans District CoVE Team Leader (504) 8621251 Frank.Vicidomina@usace.army.mil

David G. Cannon Everest International Consultants, Inc. Coastal Engineer (562) 4359309 david.cannon@everestconsultants.com

Chester Watson Biedenharn Group, LLC Hydraulics Engineer (970) 4818256 chester@chestercwatson.com

Wes Wilson EPA Region 8 Environmental Engineer (303) 3126562 Wilson.Wes@epamail.epa.gov

Sean Mickal USACENew Orleans District Project Management (504) 8622319 sean.p.mickal@usace.army.mil

John Peukert USACESt. Louis District Project Management (314) 3318063 john.peukert@usace.army.mil

Tomma Barnes USACENew Orleans District Project Management (504) 8621481 tomma.k.barnes@usace.army.mil

Pam DeLoach USACENew Orleans District Engineering Team Leader (504) 8622621 pamela.a.deloach@usace.army.mil

Aaron Bass SJB Group Coastal Scientist (225) 7693400 abass@sjbgroup.com

Carol Parsons Richards LA Office of Coastal Project & Restoration Coastal Resources Supervisor (225) 3429430 carol.richards@la.govWilliam Klein USACENew Orleans District Biologist (504) 8623540 william.p.klein@usace.army.mil

MEETING ATTENDEES

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

VALUE ENGINEERING STUDY

NAME ORGANIZATION POSITION PHONE/CELL EMAIL

Terrebonne Basin Barrier Shoreline RestorationMultipurpose Operation of Houma Navigation LockConvey Atchafalaya River Water to Northern Terrebonne Marshes VE Team and Process - 6.3


APPENDICES


Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes Appendices

APPENDICES

The following documents are provided as reference material to the results of this VE Study.

A. Coastal Impact Assistance Program Application  Houma Navigation Canal Lock, May 22, 2006; Terrebonne

Levee Conservation District

B. Conceptual floating barge gate designs

C. VE Study  Bayou Lafourche Siphon Restoration Project, July 2001; Proposal C1

D. Preparation of a MultiProject Environmental Assessment to evaluate the potential environmental impacts

associated with the removal of sand resources from Ship Shoal, offshore Central Louisiana

E. Louisiana Sand Management Working Group Meeting Minutes, 2 February 2005

F. Information on Relative SeaLevel Rise as prepared by Kevin Knuuti, P.E., Chief, Engineering Division, U.S.

Army Corps of Engineers, Sacramento, CA

G. MultiPit Breakwaters, Journal of Waterway, Port, Coastal, and Ocean Engineering, William G. McDougal,

A. Neil Williams, and Keizo Furukawa, January/February 1996

H. MMS Management of Outer Continental Shelf Material Deposits and related information


Appendix A













Appendix B






















Appendix C















Appendix D






Appendix E


Louisiana Sand Management Working Group Meeting

AGENDA - 2 February 2005

Lindy C. Boggs International Center, University of New Orleans

09:00 Open Session

I. Introductions, Housekeeping Items, Review of Agenda

II. Environmental Issues Update

A. Utilization of Benthic Communities by Fish Populations on Ridge and Shoal Features 

Allen Brooks, USGS Coastal Ecology and Conservation Research Group, Gainesville,

FL

B. Environmental Investigation of the Long-Term Use of Ship Shoal Sand Resources for

Large-Scale Coastal Restoration in Louisiana  Greg Stone, LSU [Handout No. 1]

C. Baseline Biological Studies (Shrimp and Seatrout) of Ship Shoal  Richard Condrey,

LSU [Handout No. 2]

III. LCA Comprehensive Plan Status  Tim Axtman, USACE New Orleans District

IV. Resource Issues Update

A. MMS/La DNR Cooperative Agreement  Syed Khalil, La DNR

B. MMS Position Paper on Establishing Project Priorities  Tim Redding, MMS [Handout

No. 3]

C. Louisiana Virtual SeaBed: UNO, USGS, INSTAAR  Shea Penland PIES-UNO

12:00-13:00 Lunch

V. Multiple Use Issues Update

A. Impacts of Hurricane Ivan on oil and gas infrastructure  Alex Alvarado, MMS GOM

Region

B. Update on MMS Study on Ship Shoal Oil & Gas Infrastructure Stability  Rob Nairn,

Baird & Associates [Handout No. 4]

VI. Review of Proposed Projects

A. Whiskey Island/West Flank  Brad Crawford/Chris Williams, EPA/DNR

B. Pelican Island, Rachel Sweeney, NOAA [Handout No. 5]

C. Morganza to the Gulf Hurricane Barrier  Bill Maloz, USACE New Orleans District

15:00 Closed Session (Federal, State, and Local Agencies Only)

VII. Action Items

A. Assignments and Deliverables

B. Schedules

VIII.Wrap-up, Summary, and Adjourn


MEETING MINUTES

I. Introductions, Housekeeping Items, Review of Agenda

II. Environmental Issues Update

A. Utilization of Benthic Communities by Fish Populations on Ridge and Shoal Features

Allen Brooks presented the study design and initial results for this study of Ship Shoal. They are

using both stable isotopes and gut content analyses to establish baseline data on the benthic

communities that are important components of fish diets on Ship Shoal. Stations are located in

proposed dredging areas, control areas, and off-bank areas that are north of Ship Shoal and in

deeper water. Cruises were conducted in January and December 2004 and planned for April/May

2005. He also announced three reports of interest:

1) USGS Report 2004-5198. Literature search on benthic communities. Published.

2) Analysis of 18 years of SEAMAP data on fish utilization of shoals in the Gulf of Mexico

(Sabine, Heald, Tiger, Trinity Shoals) that will be published soon.

3) Two-year study of the demersal fish on Ship Shoal, a landscape study of utilization.

Study should be completed after one more year of field data collection.

There was discussion about how the study results will be used, whether as baseline for pre-/postdredging monitoring of impacts or for EIS. MMS has already prepared an EA for dredging. It

will be important to have data on which benthic communities are important prey for fish, so that

guidelines for dredging could be developed to minimize impacts to these communities.

Coordination and exchange of samples/data/information between the USGS cruises and the LSU

biological cruises was also discussed.

B. Environmental Investigation of the Long-Term Use of Ship Shoal Sand Resources

for Large-Scale Coastal Restoration in Louisiana

Greg Stone presented information on the status of the physical tasks, which include

Quantification of local and regional hydrodynamics for statistically significant meteorological

conditions, pre-dredging. He also discussed the instrumentation and new buoy that will fill some

gaps and provide real time data for Ship Shoal. The study also includes a biological component

that was discussed by Richard Condrey in the presentation, which followed.

C. Baseline Biological Studies (Shrimp and Seatrout) of Ship Shoal

Richard Condrey of LSU presented an update on this study. He has been joining SEAMAP

cruises (July, Sept, Dec 2004) to collect additional data on Ship Shoal. Plans are for field data

collection cruises in August and October 2005 and March 2006.


III. LCA Comprehensive Plan Status

Tim Axtman gave an update on the LCA Plan with a lot of detail. The Near-term Plan was based

on projects that are highly cost effective and achievable in a relatively short period of time. The

current plan consists of (at a cost of $2 billion):

1) 15 near-term critical projects

2) Science and technology program including demonstration projects

3) Increased beneficial use

4) Modification of selected structures

5) Large-scale long-term concepts

The 2005 Work Plan will include:

1) Completion of the barrier island feasibility study

2) Science and technology program development (hire director, support will be through

funds from individual studies)

3) Develop the long-range beneficial use program

4) Conduct studies to modify/improve the Davis Pond and Caernarvon diversions

5) Long-distance sediment transport demonstration project

6) Third delta and Acadiana Bays studies

7) LCA Plan future development

IV. Resource Issues Update

A. MMS/La DNR Cooperative Agreement

Syed Khalil of DNR reported on the status of the study being conducted under the MMS/DNR

MOU to assess offshore sand sources off the Louisiana coast and create a geospatial database

(geological, environmental, and associated data) for better evaluation of the sand sources. They

have conducted detailed geophysical and geotechnical surveys of Ship Shoal blocks 88/89 and

Sandy Point. DNR estimates that 51 million cubic yards of OCS sand will be needed through

2010. DNR recommends:

1) Regional geological/geophysical surveys in other blocks of Ship Shoal and other shoals

2) Phased operation of such evaluations, consisting of:

a. Reconnaissance geophysical surveys

b. More detailed surveys in high potential sand areas

c. Vibracores where needed to confirm sand volumes

3) Continue coordination with other agencies in database design and development

4) Continue data input into database

5) Develop protocol for geophysical data collection

Barry Drucker of MMS made a comment that the results of DNRs work would be incorporated

into the proposed FY 06 MMS LA site-specific environmental study to evaluate other areas

besides Ship Shoal.


B. Louisiana Virtual SeaBed: UNO, USGS, INSTAAR

Mark Kulp of UNO presented an update on the joint USGS/UNO effort to create a geospatial

data warehouse and on-line user interface for geological and geophysical data for coastal

Louisiana (including onshore and offshore). The URL for the visualization tools will be

distributed to the LaSMWG as soon as it is available.

V. Multiple Use Issues Update

A. Impacts of Hurricane Ivan on oil and gas infrastructure 

Alex Alvarado gave a presentation on the extent of damage to oil and gas infrastructure during

Hurricane Ivan, which was extensive. MMS is planning a study to determine where the

mudslides occurred.

B. Update on MMS Study on Ship Shoal Oil & Gas Infrastructure

Rob Nairn of Baird & Associates, Inc. presented some interim results of their MMS-funded

study to determine appropriate buffers around oil and gas infrastructure. The study included rebathymetric surveys of the Holly Beach dredge pits specifically for this project. Data from other

sites were presented as well. In summary, the interim results indicate that pit morphology

evolution processes include:

Slope stability adjustment  soil type is a factor

Pit infilling (due to both regional/local sources of turbidity)

Pit margin adjustment

Berm evolution for multiple pits

The study deliverables will include recommendations for estimating buffers for different

conditions. There will not be a single buffer but guidance on how to calculate buffers for

different site conditions off Louisiana.

There was extensive discussion of the interim buffer of 300 m by DNR who are concerned over

the size of the setback/buffer which might reduce the overall extent of some borrow sites and

want the setback justified by credible scientific investigation/methodology.

VI. Review of Proposed Projects

A. Whiskey Island/West Flank

Brad Crawford of EPA provided an update of the proposed dredging of Ship Shoal for sand

placement on the West Flank of Whiskey Island. They expect to need 4 million cubic yards of

sand. They asked if stipulations would be required in the lease concerning how the sand should

be removed from the borrow site. They want to give as much leeway to the dredger to keep the

costs as low as possible. The project is now planned for initiation in Spring 2006; it has been

modified and the sand volume needed increased to protect some marsh area east of the flank.


B. Pelican Island

Rick Hartman of NOAA gave a brief update. They received $60 million for the project last year.

DNR has worked on the oyster lease issues, but there are still some delays. They had to get an

ocean dumping permit from the USEPA/ACOE. They are also working internally on sea turtle

issues. They continue to discuss the lease agreement with MMS. NOAA is collecting additional

vibracores in the southern area to get total thickness of sand since the northern area is

inaccessible because of the 300 m buffer around pipelines. They will be bidding out the project

as either hopper barges or cutterhead dredging. They expect construction to begin in 2006.

C. Morganza to the Gulf Hurricane Barrier

Bill Maloz of the ACOE provided an update on this project, which consists of:

72 miles of earthen levee

12 sector gate structures for flood control

12 environmental water control structures

Houma Navigation Canal Lock Complex

First construction is scheduled for Jun 2005. Total construction is estimated at 16 years - 2021

(assumes immediate start, steady funding stream & continuous construction) at a total cost of

$740 million. They want to use sand for the levee base following reasons: lower costs than all

earthen levee; greater stability, less time to consolidate; and it will require a smaller footprint so

there are environmental benefits. They looked at several sand sources: Ship Shoal, Cat Island

Pass, Bayou Sorrel, Horseshoe Channel, sand from Alabama disposal sites, Bonnet Carrie

spillway, and Mississippi River sediment traps. They have identified several sand stockpile areas

along the levees. Their current focus is on the sand from maintenance dredging of Cat Island

Pass, which is the closest source, therefore, sand from Ship Shoal will most likely not be

accessed for this project. They are working with DNR on modeling of the potential impacts of

using this inshore sand source.

VII. MMS Position Paper on Establishing Project Priorities

The discussion of the December 2004 version of the priorities paper included the following

questions, which focused on how to reduce impacts of oil and gas infrastructure on access to

OCS sand off Louisiana:

1) What are the MMS requirements for abandoned wells and pipelines? The suggestion was

that MMS should require removal of abandoned facilities so they will not interfere with

sand access. MMS stated that the current regulations allow abandonment in place, as

long as it does not pose conflicts with other uses of the seafloor. There was discussion

about who would pay if the operator was defunct or could not be found. MMS agreed that

they needed to discuss policy guidelines for oil and gas abandonment in good sand areas.

2) Has MMS considered designating pipeline corridors through sand areas? The State

reviews all new well requests on land to determine if it is feasible to cluster them, to

reduce the footprint of their impacts. Does MMS have this kind of authority? MMS


currently cannot officially set-aside areas for sand access. In deep water, wells are

clustered around platforms because of the costs. However, MMS has guidelines for

protection of certain features or resources, such as cultural resources. They agreed to

consider access to sand as a resource that should be protected, to be incorporated into the

plan review process. They requested that lease blocks of critical interest for sand be

identified.

3) The issue of whether MMS could set aside areas for sand access on other shoals was

raised. MMS did issue an Information to Lessees (see detailed discussion in the Priorities

Paper that was distributed prior to the meeting) that included the following:

Stipulation No. 9 - Sand Dredging Operations: Limitation on Use of Leased Area

The Minerals Management Service (MMS) is evaluating use of sand resources from the

area covered by this lease (the leased area) for nearby levee and barrier island

restoration projects. As a result, the MMS may enter into non-competitive, negotiated

sand and gravel leases with a third party during the term of this lease.

Dredging of sand from within the leased area and the associated presence of an oceangoing dredge vessel may conflict with Lessees oil and gas operations. Prior to

construction or placement of any structure for exploration and development on the leased

area, including, but not limited to, anchoring, well drilling, and pipeline and platform

placement, Lessee shall notify in writing and consult with the Chief, MMS Leasing

Division, regarding such planned activities.

The MMS will determine whether the planned activities conflict with ongoing or planned

sand dredging operations. If MMS determines that Lessees planned activities conflict

with sand dredging, the MMS will require Lessee to conduct its operations in a manner to

avoid such conflicts. In addition, MMS will coordinate all activities of the dredge

vessel(s) and service vessel(s) in order to minimize conflicts with lessees planned

activities.

MMS said that it would consider developing more detailed language that would specify the types

of requirements that could be included in priority sand areas, such as pipeline corridors.


STATUS OF RECOMMENDATIONS FROM THE MAY 2003 LA SMWG MEETING

Recommendation Status

MMS will distribute to the La SMWG the final

multi-project Environmental Assessment that

should be completed by the end of March 2004

Done.

The La SMWG will be notified of any

proposed changes to the current hazard and

archaeological survey requirements.

No proposed changes to date.

The La SMWG will provide MMS comments

on the draft prioritization process paper by 15

May 2004

Done. A new draft dated December 2004 was

presented at the February 2005 meeting.

As the USGS and UNO continue work on the

US.Seabed project in Louisiana, they should

work on estimating the uncertainty in the sand

volume estimates being generated.

On-going.

It is important for DNR to look for sand

sources inshore, including in the major river

channels, in addition to the offshore sand

shoals.

On-going.

The issue of buffers around oil and gas

infrastructure is of great concern. Work should

continue to identify risks and mitigation

strategies.

On-going. Reported interim results of current

study at the February 2005 meeting.

Work should continue on strategies to reduce

the potential conflict between access to sand

borrow sites and oil and gas leasing and

infrastructure.

On-going. New action items were identified at

the February 2005 meeting.


ATTENDEES February 2, 2005 La SMWG Meeting

1. Barry Drucker MMS (FG) Barry.Drucker@mms.gov

2. Maureen Bornholdt MMS (FG) maureen.bornholdt@mms.gov

3. Mark Rouse MMS (FG) mark.rouse@mms.gov

4. Tom Meyer MMS (FG) tom.meyer@mms.gov

5. Alvin Jones MMS (FG) alvin.jones@mms.gov

6. Jess Hunt MMS (FG) jess.hunt@mms.gov

7. Alex Alvarado MMS (FG) alex.Alvarado@mms.gov

8. David Burkholder DNR (SG) DAVIDB@dnr.state.la.us

9. Jeff Harris DNR (SG) JEFFH@dnr.state.la.us

10. Syed Khalil DNR (SG) SyedK@dnr.state.la.us

11. Chris Williams DNR (SG) chrisw@dnr.state.la.us

12. Len Bahr GOCA (SG) len.bahr@gov.state.la.us

13. Heather Finley LDWF (SG) Finley_H@wlf.state.la.us

14. Jim Hanifen LDWF (SG) Hanifin_J@wlf.state.la.us

15. Bill Klein ACOE (FG) William.P.Klein.Jr@mvn02.usace.army.mil

16. Del Britsch ACOE (FG) Louis.D.Britsch@mvn02.usace.army.mil

17. Tim Axtman ACOE (FG) Timothy.J.Axtman@mvn02.usace.army.mil

18. John Lopez ACOE (FG) john.h.lopez@mvn02.usace.army.mil

19. Brad Crawford EPA (FG) brad.crawford@epa.gov

20. Rick Hartman NMFS (FG) richard.hartman@noaa.gov

21. Kevin Roy FWS (FG) kevin_roy@fws.gov

22. Allan Brooks USGS (FG) Allen_brooks@usgs.gov

23. Jim Flocks USGS (FG) jflocks@usgs.gov

24. Bill Good LGS (SG) billgood@lsu.edu

25. Shea Penland UNO (A) spenland@uno.edu

26. Mark Kulp UNO (A) mkulp@uno.edu

27. Sammi Briuglio UNO (A) sbriuglio@uno.edu

28. Richard Condrey LSU (A) coecnd@lsu.edu

29. Greg Stone LSU (A) gagreg@lsu.edu

30. Ancil Taylor Bean Stuyvesant (D) ataylor@cfbean.com

31. Jeff Andrews CPE (PC) jandrews@coastalplanning.net

32. Rick Smith Weeks Marine (PC) rdsmith@weeksmarine.com

33. Daniel L. Bolinger DMJM & Harris (PC) daniel.bolinger@dmjmharris.com

34. Ancil Taylor Been Stuyvesant (PC) ataylor@cfbean.com

35. Russell Young Burk-Kleinpeter, Inc. (PC) ryoung@bkiusa.com

36. Michael Caracher Burk-Kleinpeter, Inc. (PC) mcaracher@bkiusa.com

37. Miles O. Hayes RPI Louisiana, Inc. (PC) mhayes@researchplanning.com

38. Rebecca Murphey RPI Louisiana, Inc. (PC) rmurphey@researchplanning.com

39. Rob Nairn Baird & Associates (PC) rnairn@baird.com

40. Jacqui Michel Research Planning, Inc.

(PC on behalf of MMS) jmichel@researchplanning.com


Appendix F














Appendix G


Downloaded 05 May 2009 to 155.76.159.253. Redistribution subject to ASCE license or copyright; see http://pubs.asce.org/copyright


Downloaded 05 May 2009 to 155.76.159.253. Redistribution subject to ASCE license or copyright; see http://pubs.asce.org/copyright


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Downloaded 05 May 2009 to 155.76.159.253. Redistribution subject to ASCE license or copyright; see http://pubs.asce.org/copyright


Downloaded 05 May 2009 to 155.76.159.253. Redistribution subject to ASCE license or copyright; see http://pubs.asce.org/copyright


Downloaded 05 May 2009 to 155.76.159.253. Redistribution subject to ASCE license or copyright; see http://pubs.asce.org/copyright


Downloaded 05 May 2009 to 155.76.159.253. Redistribution subject to ASCE license or copyright; see http://pubs.asce.org/copyright


Appendix H


From: Gambino, Stephanie [mailto:Stephanie.Gambino@mms.gov]

Sent: Monday, June 08, 2009 6:14 PM

To: Klein, William P Jr MVN

Cc: Gambino, Stephanie; Stacie Merritt

Subject: RE: VE creative idea MMS regulate Ship Shoal

Bill

The MMS Marine Minerals Program manages sand and gravel resources on the Federal outer

continental shelf (OCS) via a 5 year rolling calendar. We believe the rolling calendar allows us

to allocate our limited funding and personnel resources in a way which balances stakeholders'

needs and provides adequate and timely information on those offshore areas where sand

would likely be needed first.

In June 2007, we sent a letter to all stakeholders (Federal, State, and other) requesting

information on potential projects using OCS sand and gravel resources in the next 5 years.

Based upon MMS resources and stakeholders' responses regarding project timelines, a

maximum of 2 projects per quarter were scheduled.

Most recently, we sent another request in April 2009 to update the calendar; responses were

due June 1, 2009. We intend to publish it in the Federal Register (FR) in the third quarter of

2009. It is anticipated that we will continue to schedule a maximum of 2 projects per quarter.

If information on a project is not submitted prior to our publishing the calendar in the FR, the

project will not be included on the calendar and will likely not be able to be completed

according to the negotiated agreement requestor's desired timeline. Further, if a scheduled

project can not be undertaken within the agreed upon timeframe, there is the possibility that

the project will be moved to the next open slot on the calendar, which could potentially lead to

significant delays in project completion. The MMS plans to publish the OCS sand and gravel

rolling calendar twice a year.

Sand and gravel resource evaluations and studies specific to Ship Shoal can be found at:

Ship Shoal Resource Evaluation:

http://www.mms.gov/sandandgravel/MarineMineralResourceEvaluation.htm#Louisiana

Ship Shoal Studies:

http://www.mms.gov/sandandgravel/MarineMineralStudies.htm#Louisiana

All MMP Resource Evaluations can be found at:

http://www.mms.gov/sandandgravel/MarineMineralResourceEvaluation.htm

All MMP studies can be found at:

http://www.mms.gov/sandandgravel/MarineMineralStudies.htm


Lastly, the FY 2010 proposed budget does have some money allocated for sand and gravel

resource evaluation and studies, but not necessarily at Ship Shoal.

If you need any additional information, please let me know.

Regards,

Stephanie M. Gambino

Minerals Management Service

Gulf of Mexico Region

Coastal Programs Section

1201 Elmwood Park Blvd.

Mail Stop 5450

New Orleans, LA 70123

voice: (504) 7362856

fax: (504) 7362502


Value Management Strategies, Inc.

Offices in Escondido, Sacramento, and Alameda, California; Grand Junction, Colorado; Sarasota, Florida;

Marietta, Georgia; Portland, Oregon; Seattle, Washington; Merriam, Kansas; and Great Falls, Montana


June 2009 June 2009 June 2009 June 2009

Value Management

Strategies, Inc.

Value Engineering Study Report

Terrebonne Basin Barrier Shoreline Restoration

Multipurpose Operation of Houma Navigation Lock

Convey Atchafalaya River Water to Northern Terrebonne Marshes

U.S. ARMY CORPS OF ENGINEERS, NEW ORLEANS DISTRICT

Value Management

Strategies, Inc.Value Engineering Study Report Terrebonne Basin Barrier Shoreline Restoration Multipurpose Operation of Houma Navigation Lock Convey Atchafalaya River Water to Northern Terrebonne Marshes

U.S. ARMY CORPS OF ENGINEERS, NEW ORLEANS DISTRICT

Value Management

Strategies, Inc.Value Engineering Study Report Terrebonne Basin Barrier Shoreline Restoration Multipurpose Operation of Houma Navigation Lock Convey Atchafalaya River Water to Northern Terrebonne Marshes

U.S. ARMY CORPS OF ENGINEERS, NEW ORLEANS DISTRICT

Value Management

Strategies, Inc.Value Engineering Study Report Terrebonne Basin Barrier Shoreline Restoration Multipurpose Operation of Houma Navigation Lock Convey Atchafalaya River Water to Northern Terrebonne Marshes

U.S. ARMY CORPS OF ENGINEERS, NEW ORLEANS DISTRICT



APPENDIX I

ADAPTIVE MANAGEMENT / MONITORING

PLAN


Louisiana Coastal Area (LCA) Program:

Terrebonne Basin Barrier Shoreline Restoration

Project

Feasibility-Level Monitoring and Adaptive

Management Plan

September 29, 2010


TABLE OF CONTENTS

1.0 INTRODUCTION ....................................................................................................... 1

1.1 Authorization for Adaptive Management in the LCA Program .............................. 1

1.2 Procedure for Drafting Adaptive Management Plans for LCA Projects ................. 1

1.3 LCA Communication Structure for Implementation of Adaptive Management ..... 3

2.0 PROJECT ADAPTIVE MANAGEMENT PLANNING ............................................ 4

2.1 Project Goals and Objectives................................................................................... 5

2.2 Management and Restoration Actions..................................................................... 5

2.3 Conceptual Ecological Model for Monitoring and Adaptive Management............. 6

2.4 Sources of Uncertainty............................................................................................. 6

3.0 RATIONALE FOR ADAPTIVE MANAGEMENT................................................... 7

3.1 Adaptive Management Program for the Terrebonne Basin Barrier Shoreline

Restoration Project.......................................................................................................... 8

4.0 MONITORING............................................................................................................ 8

4.1 Rationale for Monitoring ......................................................................................... 8

4.2. Monitoring Plan for the Terrebonne Basin Barrier Shoreline Restoration Project.. 9

4.2.1 Monitoring Procedures.................................................................................... 11

4.2.2 Use of Monitoring Results and Analyses........................................................ 13

5.0 DATABASE MANAGEMENT ................................................................................ 13

5.1 Description and Location....................................................................................... 13

5.2 Data Storage and Retrieval .................................................................................... 14

5.3 Analysis, Summarizing, and Reporting ................................................................. 14

6.0 ASSESSMENT.......................................................................................................... 14

6.1 Assessment Process ............................................................................................... 14

6.2 Variances and Success ........................................................................................... 14

6.3 Frequency of Assessments..................................................................................... 15

6.4 Documentation and Reporting ............................................................................... 15

7.0 DECISION-MAKING ............................................................................................... 16

7.1 Decision Criteria .................................................................................................... 16

7.2 Potential Adaptive Management Measures ........................................................... 16

7.3 Project Close-Out.................................................................................................... 17

8.0 COSTS FOR IMPLEMENTATION OF MONITORING AND ADAPTIVE

MANAGEMENT PROGRAMS....................................................................................... 17

8.1 Costs for Implementation of Monitoring Program ................................................ 17

8.2 Costs for Implementation of Adaptive Management Program............................... 18

9.0 LITERATURE CITED ............................................................................................... 20

List of Figures

Figure 1. Set-up Phase of the LCA Adaptive Management Framework.

Figure 2. Implementation Phase of the LCA Adaptive Management Framework.

Figure 3. LCA Communication Structure for Implementation of Adaptive Management.


List of Tables

Table 1. Preliminary Cost Estimates for Implementation of the Monitoring Program for the LCA

Terrebonne Basin Barrier Shoreline Restoration Project.

Table 2. Preliminary Cost Estimates for Set-up of Adaptive Management Program for the LCA

Terrebonne Basin Barrier Shoreline Restoration Project.

Table 3. Preliminary Cost Estimates for Implementation of Adaptive Management Program for

the LCA Terrebonne Basin Barrier Shoreline Restoration Project.

List of Attachments

Annex 1. LCA Terrebonne Basin Barrier Shoreline Restoration Project Conceptual Ecological

Model


1.0 INTRODUCTION

This document outlines the feasibility level monitoring and adaptive management plan for the

Louisiana Coastal Area (LCA) Terrebonne Basin Barrier Shoreline Restoration (TBBSR)

Project. The LCA Adaptive Management Framework Team developed this monitoring and

adaptive management plan with assistance from the Project Delivery Team (PDT). This plan

identifies and describes the monitoring and adaptive management activities proposed for the

TBBSR Project and estimates their cost and duration. This plan will be further developed in the

preconstruction, engineering, and design (PED) phase as specific design details are made

available.

1.1 Authorization for Adaptive Management in the LCA Program

The LCA Ecosystem Restoration Study Chiefs Report (2005) states (for the 15 near-term

features aimed at addressing the critical restoration needs)

the feasibility level of detail decision documents will identify specific sites, scales,

and adaptive management measures, and will optimize features and outputs necessary to

achieve the restoration objectivesto ensure that LCA ecosystem restoration objectives

are realized, monitoring and adaptive management must be a critical element of LCA

projects.

Section 7003(a) of Water Resources Development Act of 2007 (WRDA 2007) stipulates:

The Secretary may carry out a program for ecosystem restoration, Louisiana Coastal

Area, Louisiana, substantially in accordance with the report of the Chief of Engineers,

dated January 31, 2005.

Additionally, Section 2039 of WRDA 2007 directs the Secretary of the Army to ensure that,

when conducting a feasibility study for a project (or component of a project) for ecosystem

restoration, the recommended project includes a plan for monitoring the success of the ecosystem

restoration. The implementation guidance for Section 2039, in the form of a CECW-PB Memo

dated 31 August 2009, also requires that an adaptive management plan be developed for all

ecosystem restoration projects.

At the programmatic level, knowledge gained from monitoring one project can be applied to

other projects. Opportunities for this type of adaptive management are common within the LCA

Ecosystem Restoration Study (USACE 2004), which also builds upon lessons learned in other

related efforts such as the Coastal Wetlands Planning, Protection and Restoration Act

(CWPPRA). Oversight by the LCA Science and Technology (S&T) Program and the LCA

Adaptive Management Planning Team provides the basic structure to ensure that knowledge

gained is effectively shared across programs and projects.

1.2 Procedure for Drafting Adaptive Management Plans for LCA Projects

The U.S. Army Corps of Engineers, Mississippi Valley Division, New Orleans District (USACE

MVN), Louisiana Office of Coastal Protection and Restoration (OCPR), and the LCA S&T

Office collaborated to establish a general framework for adaptive management to be applied to

all LCA projects. The framework for adaptive management is consistent with the previously

mentioned implementation guidance, as well as with the guidance provided by the U.S. Fish and

Wildlife Service (USFWS) and the National Oceanic and Atmospheric Administration's

(NOAA) "Availability of a Final Addendum to the Handbook for Habitat Conservation Planning


and Incidental Take Permitting Process in Federal Register vol. 65, No. 106 35242. The LCA

adaptive management framework includes both a set-up phase (Figure 1) and an implementation

phase (Figure 2).

Figure 1. Set-up Phase of the LCA Adaptive Management Framework.

Figure 2. Implementation Phase of the LCA Adaptive Management Framework.


1.3 LCA Communication Structure for Implementation of Adaptive Management

To execute an adaptive management strategy for the LCA Ecosystem Restoration Study, a

communication structure has been identified (Figure 3). The structure includes an establishment

of clear lines of communication between LCA Program Management, an Adaptive Management

Planning Team, the S&T Office, PDTs, and stakeholders. Successful implementation will require

the right resources being coupled at the right time to support the framework components.

Figure 3. LCA Communication Structure for Implementation of Adaptive Management.

As part of the LCA Program communication structure for implementation of adaptive

management (Figure 3), an LCA Adaptive Management Planning Team will be established. This

team will be led jointly by a Senior Planner from the USACE and a counterpart from the OCPR.

Other team members include USACE and State support staff and representatives from USFWS,

NOAA, Natural Resources Conservation Service (NRCS), and Louisiana Department of Wildlife

and Fisheries (LDWF). These members will be selected in part based on their knowledge of

ecosystem restoration, coastal Louisiana ecosystems and adaptive management. Other resources

and expertise will be brought in as needed. This team will be responsible for presenting project

and program adaptive management action recommendations to the LCA Management Team.

The LCA Science and Technology (S&T) Office was established by the USACE and the State of

Louisiana (the non-Federal sponsor) to effectively address coastal ecosystem restoration needs

and to provide a strategy, organizational structure, and process to facilitate integration of science

and technology into the adaptive management process. Under the Adaptive Management

Framework, there are five primary elements in the LCA S&T Program, and each element differs


in emphasis and requirements. These elements include: (1) science information Needs, (2) data

acquisition and monitoring, (3) modeling, (4) research, and (5) data management and reporting

(assessment).

Under the LCA S&T Office, an Assessment Team will be established. This team will be led by

the S&T Director and a representative of the U.S. Geological Survey (USGS) who will also

serve as direct liaisons between the S&T Assessment Team and the LCA Adaptive Management

Planning Team. Other members will be identified from Federal and State agencies.

Responsibilities of this team include analysis and reporting of data to the LCA Adaptive

Management Planning Team and the LCA Program Management Team.

2.0 PROJECT ADAPTIVE MANAGEMENT PLANNING

Specific LCA PDTs assisted the LCA Adaptive Management Framework Team in developing

the monitoring and adaptive management plan for each specific project. The members of the

Adaptive Management Framework Team for this project were Tomma Barnes, USACE-MVN;

Steve Bartell, E2 Consulting Engineers; Laura Brandt, U.S. Fish and Wildlife Service; Craig

Fischenich, USACE/Engineer Research and Development Center; Barbara Kleiss, USACE

Mississippi Valley Division; Carol Parsons Richards, OCPR; Greg Steyer, USGS National

Wetlands Research Center; and Darin Lee, OCPR.

The resulting adaptive management plan for the TBBSR project describes and justifies whether

adaptive management is needed in relation to the proposed project management alternatives

identified in the Feasibility Study. The plan also identifies how adaptive management would be

conducted for the project and who would be responsible for this project-specific adaptive

management program. The developed plan outlines how the results of the project-specific

monitoring program would be used to adaptively manage the project, including specification of

conditions that would demonstrate project success.

The Adaptive Management Plan for this project reflects a level of detail consistent with the

project Feasibility Study. The primary intent was to develop monitoring and adaptive

management actions appropriate for the projects restoration goals and objectives. The specified

management actions permit estimation of the adaptive management program costs and duration

for the project.

The following adaptive management plan section (1) identifies the restoration goals and

objectives identified for the TBBSR project, (2) outlines management actions that can be

undertaken to achieve the project goals and objectives, (3) presents a conceptual ecological

model that relates management actions to desired project outcomes, and (4) lists sources of

uncertainty that would recommend the use of adaptive management for this project. Subsequent

sections describe monitoring, assessment, decision-making, and data management in support of

adaptive management.

The level of detail in this plan is based on currently available data and information developed

during plan formulation as part of the feasibility study. Uncertainties remain concerning the

exact project features, monitoring elements, and adaptive management opportunities.

Components of the monitoring and adaptive management plan, including costs, were similarly

estimated using currently available information. Uncertainties will be addressed in the

preconstruction, engineering, and design (PED) phase a detailed monitoring and adaptive


management plan, including a detailed cost breakdown, will be drafted as a component of the

design document.

2.1 Project Goals and Objectives

During initial stages of project development, the project delivery team, with stakeholder input,

developed restoration goals and objectives to be achieved by the TBBSR project. These goals

and objectives were subsequently refined through interactions with the LCA Adaptive

Management Framework Team. The overarching goal of this project is to reduce degradation and

deterioration of the barrier island system in Terrebonne Basin. This project has been planned to

help achieve and sustain a larger-scale coastal ecosystem that can support and protect the

environment, economy, and culture of southern Louisiana and thereby contribute to the wellbeing of the Nation. The specific restoration objectives for the TBBSR project are to:

Restore the barrier structures to ensure their ability to provide geomorphic and hydrologic

form and function for the 50-year period of analysis.

Restore and improve various barrier island habitats that provide essential habitats for fish,

migratory birds, and other terrestrial and aquatic species, mimicking, as closely as

possible, conditions which occur naturally in the area.

Increase sediment input to supplement long-shore sediment transport processes along the

gulf shoreline by mechanically introducing compatible sediment, and increasing the

ability of the restored area to continue to function and provide habitat with minimum

continuing intervention.

2.2 Management and Restoration Actions

The PDT performed a thorough plan formulation process to identify potential management

measures and restoration actions that address the project objectives. Many alternatives were

considered, evaluated, and screened in producing a final array of alternatives. The PDT

subsequently identified a National Ecosystem Restoration (NER) Plan.

A four-island plan, which consists of Raccoon Plan E with Terminal Groin, Whiskey Plan C,

Trinity Plan C, and Timbalier Plan E was selected as the NER Plan because it was a Best Buy

that fulfills the planning objectives of the project. However, the NER Plan cannot be constructed

under the current WRDA 2007 authorization. Therefore Whiskey Island Plan C, a subset of the

NER Plan, has been proposed as the first component of construction. The plan restores the

geomorphic form and ecological function of the island and provides an additional five years of

protection from background erosion and subsidence. Immediately after construction (TY1), the

first component of construction will add 469 acres of habitat (dune, intertidal, and supratidal) to

the existing 803-acre island footprint, increasing the size of the island to 1,272 acres. This

includes 65 acres of dune, 830 acres of supratidal, and 377 acres of intertidal habitat.

The island will require two renourishment intervals in order to maintain the geomorphologic

form and ecologic function throughout the 50-year period of analysis. The first renourishment

event will occur at TY20 and will include the addition of the same amount of dune and supratidal

beach acres that was originally created in TY1 (i.e. add a Plan C to the remaining island structure

at TY20). The second renourishment interval will occur at TY 40 and will include the addition of

the same amount of dune and supratidal beach acres needed to construct a Plan B template. No

additional marsh material will be added.


2.3 Conceptual Ecological Model for Monitoring and Adaptive Management

As part of the planning process, members of the TBBSR project PDT developed a conceptual

ecological model to represent current understanding of ecosystem structure and function in the

project area, identify performance measures, and help select parameters for monitoring (Annex

1). The model illustrates the affects of important natural and anthropogenic activities that result

in different ecological stressors on the system. The effects of concern can be measured for

selected performance measures defined as specific physical, chemical, and biological attributes

of the system.

2.4 Sources of Uncertainty

Adaptive management provides a coherent process for making decisions in the face of

uncertainty. Scientific uncertainties and technological challenges are inherent with any largescale ecosystem restoration project. Below is a list of uncertainties associated with restoration of

the barrier island ecosystems included in the TBBSR project.

Rates of relative sea level rise;

Detailed bathymetry data throughout the coast;

Detailed topographic data throughout the coast;

Sediment sources for reestablishment of barrier islands; and

Physical processes that control the retreat of barrier islands in Louisiana.

In the future, a regional sediment budget should be developed to quantify the movements of sand

and fine sediments in response to sea level rise, storm impacts, and longshore transport losses to

inlets. The forcing functions within the sediment budget that would require quantitative data

include profile response to sea level rise, gradients in longshore transport and sediment losses to

ebb-tidal deltas. Monitoring of shoreline and volumetric losses above and below the water

surface will be required to refine the sediment budget. The refined budget will be in turn used to

refine the TBBSR design templates.

The 2004 LCA Plan includes best management practices specific to design and construction of

barrier islands (USACE, 2004c). Elements of barrier island restoration that warrant further

refinement and incorporation into future plans include:

Depth of closure;

Design template;

Advanced fill;

Monitoring and maintenance;

Nourishment of both Gulf and Bay shorelines of barrier islands;

Breach and inlet closures;

Restoration priority; and

Mainland and bay shorelines.


Potential climate change issues, such as sea level rise, in addition to regional subsidence rates are

significant scientific uncertainties for all LCA projects. These issues were incorporated in the

plan formulation process and will be monitored by gathering data on water levels, salinities, and

land elevation. These data will inform adaptive management actions, but future climate change

projections remain highly uncertain at this time.

3.0 RATIONALE FOR ADAPTIVE MANAGEMENT

The primary incentive for implementing an adaptive management program is to increase the

likelihood of achieving desired project outcomes given the identified uncertainties. All projects

face uncertainties with the principal sources of uncertainty including (1) incomplete description

and understanding of relevant ecosystem structure and function, (2) imprecise relationships

between project management actions and corresponding outcomes, (3) engineering challenges in

implementing project alternatives, and (4) ambiguous management and decision-making

processes.

Given these uncertainties, adaptive management provides an organized, coherent, and

documented process that defines management actions in relation to measured project

performance compared to desired project outcomes. In the case of the TBBSR project, the

adaptive management program will use the results of continued project monitoring to manage the

project in order to achieve the previously stated project goals and objectives. Adaptive

management establishes the critical feedback of information from project monitoring to inform

project management and promote learning through reduced uncertainty.

Several questions were considered to determine if adaptive management should be applied to the

TBBSR project:

1) Are the ecosystems to be restored sufficiently understood in terms of hydrology and

ecology, and can project outcomes be accurately predicted given recognized natural and

anthropogenic stressors?

2) Can the most effective project design and operation to achieve project goals and

objectives be readily identified?

3) Are the measures of this restoration projects performance well understood and agreed

upon by all parties?

4) Are project management actions sufficiently flexible to be adjusted in relation to

monitoring results?

A NO answer to questions 1-3 and a YES answer to question 4 identifies the project as a

candidate that could benefit from adaptive management. The Framework Team and the PDT

decided that the project meets these qualifications, and, therefore, is a candidate for adaptive

management.

For this project, there are a number of uncertainties associated with ecosystem function and how

the ecosystem components of interest will respond to the restoration project. In addition, there

are associated uncertainties about the best design and operation for the project. Using an adaptive

management approach during project planning provided a mechanism for building flexibility into

project design and for providing new knowledge to better define anticipated ecological

responses. This also enabled better selection of appropriate design to meet the project objectives.


Additionally, an adaptive management approach will help define project success and identify

outcomes that should realistically be expected for the project.

3.1 Adaptive Management Program for the Terrebonne Basin Barrier Shoreline

Restoration Project

An Adaptive Management Program for the TBBSR project is needed to ensure proper

implementation of adaptive management. The Program will also facilitate coordination of

projects within the LCA Program and coordination among PDTs, the LCA S&T, and LCA

Program Management. The LCA Adaptive Management Planning Team will lead all LCA

project and program adaptive management recommendations and actions. This team is

responsible for ensuring that monitoring data and assessments are properly used in the adaptive

management decision making process. If this team determines that adaptive management actions

are needed, the team will coordinate a path forward with project planners and project managers.

Other PDT members may be solicited as needed; for instance, if the adaptive management

measure is operational, operations and hydraulics representatives might be asked to participate.

The LCA Adaptive Management Planning Team is also responsible for project documentation,

reporting, and external communication. Tables 2 and 3 list the cost estimates for these adaptive

management activities.

4.0 MONITORING

Independent of adaptive management, an effective monitoring program will be required to

determine if the project outcomes are consistent with original project goals and objectives. The

power of a monitoring program developed to support adaptive management lies in the

establishment of feedback between continued project monitoring and corresponding project

management. A carefully designed monitoring program is a central component to the TBBSR

adaptive management program.

4.1 Rationale for Monitoring

Monitoring must be closely integrated with all other LCA adaptive management components

because it is the key to the evaluation and learning components of adaptive management. Project

and system level objectives must be identified to determine appropriate indicators to monitor. In

order to be effective, monitoring designs must be able to distinguish between ecosystem

responses that result from project implementation (i.e., management actions) and natural

ecosystem variability. In coastal Louisiana, there are many existing restoration and protection

projects already constructed, and many more are being planned under different authorizations

and programs. In combination, these projects will ultimately influence much of coastal

Louisiana. Monitoring must therefore be conducted across a range of carefully selected scales to

assess short-term project performance and to characterize longer-term, system-wide trends and

conditions.

Achieving monitoring objectives will require monitoring that focuses on different spatial and

temporal scales. Spatially, a project might achieve local objectives, but have little or no

measurable effect at larger scales. Temporally, monitoring designs need to consider the amount

of time it could take for slowly changing ecological variables to respond to management actions.

Additionally, monitoring should be designed to measure the persistence of near-term effects.

Larger-scale effects will generally take longer to develop and longer to detect than more

localized effects.


Monitoring for large scale effects can be more difficult than for local effects because the

ecological linkages become more complicated as factors outside project boundaries influence

processes and biota that affect desired project outcomes. The benefits of improved habitat in one

location may be counteracted by degradation at another location, thus showing no overall benefit

at large scales. In addition, monitoring at large scales can involve changes in underlying

conditions over time or space and be very labor intensive. When possible, specific monitoring

and large scale information needs should be interrelated. In some cases, large scale monitoring

may be just an extension of local monitoring in space and time, but it may also involve designs

and procedures that are separate from site specific monitoring and extend beyond the purview of

the project teams.

When possible, specific monitoring and large scale information needs should be integrated with

existing monitoring efforts that are underway in coastal Louisiana. For example, the CWPPRA

program has been monitoring restoration and protection projects in coastal Louisiana since 1990

(Steyer and Stewart 1992, Steyer et al. 1995). The monitoring program incorporates a systemlevel wetland assessment component called the Coastwide Reference Monitoring System

(CRMS-Wetlands, Steyer et al. 2003). The Barrier Island Comprehensive Monitoring (BICM)

Program (Troutman et al. 2003) was established under the LCA S&T Office in 2005 as called for

in the LCA Plan to complement CRMS-Wetlands and integrate coastal shoreline monitoring for

numerous restoration efforts. CRMS-Wetlands and BICM provide system-wide performance

measures that are evaluated to help determine the cumulative effects of restoration and protection

projects in coastal Louisiana. LCA monitoring plans should benefit from existing monitoring

networks to the extent practicable and participate in the implementation of CRMS-Wetlands and

BICM. Such participation can maintain the data consistencies necessary to conduct project and

programmatic adaptive management.

4.2. Monitoring Plan for the Terrebonne Basin Barrier Shoreline Restoration

Project

According to the CECW-PB Memo dated 31 August 2009, Monitoring includes the systemic

collection and analysis of data that provides information useful for assessing project

performance, determining whether ecological success has been achieved, or whether adaptive

management may be needed to attain project benefits. The following discussion outlines key

components of a monitoring plan that will support the project Adaptive Management Program.

The plan identifies performance measures along with desired outcomes (i.e. targets) in relation to

specific project goals and objectives. A performance measure includes specific feature(s) to be

monitored to determine project performance. In addition, if applicable, a risk endpoint was

identified. Risk endpoints measure undesirable outcomes of a management or restoration action.

A monitoring design was established to determine if the desired outcome or risk endpoint is met.

Upon completion of the TBBSR project, monitoring for ecological success and adaptive

management will be initiated and will continue until ecological success is achieved, as defined

by the project-specific objectives. This monitoring plan includes the minimum monitoring

actions to evaluate success and to determine adaptive management needs. Although the law

allows for a ten-year cost-shared monitoring plan, ten years of monitoring may not be required.

Once ecological success has been achieved, which may occur in less than ten years postconstruction, no further monitoring will be performed. If success cannot be determined within

that ten-year period of monitoring, any additional monitoring will be a non-Federal


responsibility. This plan estimated monitoring costs for a period of ten years because that is the

maximum allowed federal contribution to monitoring As soon as ecological success is achieved,

monitoring will cease.

The following discussion outlines key components of a monitoring plan that will support the

LCA TBBSR project Adaptive Management Program. The plan identifies performance measures

along with desired outcomes and monitoring designs in relation to specific project goals and

objectives. Additional monitoring is identified as supporting information needs that will help

further understand and corroborate project effects.

Objective 1: Restore the barrier structures to ensure their ability to provide geomorphic and

hydrologic form and function.

Performance Measure 1a: Aerial extent

Desired Outcome: Reduce land loss within the TBBSR project area below the historic average

(1880s  2005)

Desired Outcome: Maintain an aerial extent that matches the predicted aerial extent of the

associated design template at a particular point in time

Monitoring Design: Aerial photography and LiDAR surveys will be used to assess the islands

dimensions over time. One pre-construction and four to five post-construction acquisitions will

be obtained.

Performance Measure1b: Island volume

Desired Outcome: Maintain an island volume that matches the predicted island volume of the

associated design template at a particular point in time

Desired Outcome: Reduce volume loss within the TBBSR project area below the historic

average (1880s  2005)

Monitoring Design: LiDAR and bathymetric surveys will be used to assess the islands

volumes over time. One pre-construction and five post-construction acquisitions will be

obtained.

Objective 2: Restore and improve various barrier island habitats that provide essential habitats

for fish, migratory birds, and other terrestrial and aquatic species, mimicking, as closely as

possible, conditions which occur naturally in the area.

Performance Measure 2: Habitat composition

Desired Outcome: Provide a distribution of acreage between habitat types that matches the

predicted acreages of the associated design template at a particular point in time

Monitoring Design: Habitats will be classified using aerial photography to assess trends in

conversion of beach and marsh to open water. One pre-construction and four post-construction

acquisitions will be obtained.

Objective 3: Increase sediment input to supplement long-shore sediment transport processes

along the gulf shoreline by mechanically introducing compatible sediment, and increasing the

ability of the restored area to continue to function and provide habitat with minimum continuing

intervention.

Performance Measure 3: Island elevation changes


Desired Outcome: Maintain elevation and bathymetric profiles that match the predicted profiles

of the associated design template at a particular point in time

Monitoring Design: Bathymetric and topographic surveys will be used to determine the crossshore profile and volumes of the barrier islands in order to characterize the changes that are

occurring in the sediment budget, barrier platform stability, and inlet response over time. One

pre-construction and five post-construction acquisitions will be obtained.

Supporting Information Need: Geotechnical and sediment properties will be identified using

push cores and grab samples to better understand sediment transport processes

Risk Endpoint: Erosion rates

Desired Outcome: Avoid inducing or increasing down drift erosion through the use of hard

structures. The benefits and/or impacts of hard structures on sediment transport can be assessed

by comparing the actual longshore erosion rate measured along the beaches to the predicted

erosion rates of the associated design template at a particular point in time. Because impacts can

occur at a distance from the structure(s), monitoring should cover the entire reach.

Monitoring Design: LiDAR and bathymetric surveys will be used to determine downdrift

erosion. One pre-construction and five post-construction acquisitions will be obtained.

Supporting Information Need: Potential scouring around hard structures will be assessed

using field reconnaissance

Risk Endpoint: Sediment capture and hypoxia

Desired Outcome: Understand sediment pathways, evolution of the side slopes and

environment (hypoxia) of borrow pits after dredging and over a period of time

Monitoring Design: A close-spaced grid-pattern bathymetric survey will be conducted followed

by sampling of bottom sediments. The bathymetric survey will be appended to any such survey

undertaken in the vicinity. One pre-construction and five post-construction acquisitions will be

obtained.

4.2.1 Monitoring Procedures

The following monitoring procedures will provide the information necessary to evaluate the

previously identified project objectives for the TBBSR project. This plan proposes one year of

intensive monitoring concentrated on Raccoon Island during PED to establish a detailed baseline

condition. This intensive monitoring will continue three years post-construction to evaluate

immediate response to the proposed restoration of Raccoon Island. This intensive monitoring

will followed by seven years of data collected through the Barrier Island Comprehensive

Monitoring (BICM) Program to evaluate influences of the project on the Terrebonne Basin

Barrier Shoreline system.

The BICM data collection program, a collaborative program between the State of Louisiana, the

USACE, USGS, and the University of New Orleans, is designed to monitor the mainland

shoreline of the south Louisiana coast, with special emphasis on the barrier shorelines and barrier

islands. Variables monitored by BICM include bathymetry, topography, shoreline change,

habitats, and storm assessment protocol. The BICM Program began in 2005.


The purpose of this project is to contribute to the overall structure and function of the Terrebonne

Barrier Shoreline system by maintaining aerial extent and habitat distribution on Raccoon Island.

This plan proposes monitoring accordingly, by focusing on the structure and function of Raccoon

Island initially to be followed by monitoring of system-level structure and functionality. The

PDT is assuming that by providing island and system structure and function, specific vegetation

and wildlife will respond accordingly; therefore, these responses are not proposed for

monitoring.

Bathymetric/Topographic Surveys: A combination of bathymetric and topographic surveys

will be used to determine the cross-shore profile and volumes of the barrier islands. One preconstruction topographic and bathymetric survey will be conducted and used with existing

LiDAR topographic surveys acquired in August 2001, October 2002 and 2006, and a

bathymetric survey conducted in 2006 under the BICM program, as the standards for future

changes in the islands dimensions. Five post-construction topographic and bathymetric surveys

will be conducted within the first 10 years and data collected will be used to develop elevation

models to compare elevation and volumetric changes within compatible survey areas. LiDAR

surveys will be conducted as per methods detailed in Hansen and Howd (2008). LiDAR surveys

will cover the complete island shoreline and extend inland approximately 1 km to cover the

whole island including the marshes. The resulting data will provide a density of approximately 1

elevation point per square meter and are accurate to approximately 10 - 15 cm vertical elevation

depending on LiDAR system used.

Bathymetry data will be collected as per Miner et al. (2009) along transects every 1500 ft (457.2

m) on both the gulf and bay sides of the island out to 2 km. Gulf transects extend to 4 km

offshore. Data will be collected along transects 4500 ft (1371.6 m) apart from 2 km to 4 km

offshore. . Project surveys conducted as part of the design and construction process will occupy

pre-existing transects at a minimum, and data will be collected at a minimum of every 100 ft or

at any major change in elevation. The borrow sites will also be surveyed as part of any survey

effort. Also included with surveys will be tying in elevation of any settlement plates or structures

installed on each island during construction.

Aerial Photography/Habitat Classification/Shoreline Position: To determine shoreline

position changes and habitat types and changes of vegetated and non-vegetated areas within the

project area, near-vertical, color-infrared photography will be acquired during pre-construction

and used with existing habitat classifications conducted in 1996, 2002, 2004, and 2005 and

shoreline position assessments from 1887, 1934, 1996, 2004, and 2005 as a pre-construction

standard for future changes in the islands habitat classification and shoreline position (island

dimensions and vegetation communities). Four post-construction near-vertical, color-infrared

photographic acquisitions will be conducted within the first 10 years and data collected will be

used to develop habitat and shoreline change models to compare with predicted habitat and

island dimensions. The photography will be geo-rectified, mosaiced, and classified using

standard operating procedures (Fernley et al. 2009, Martinez et al. 2009) developed under the

BICM program. Analysis and mapping of habitat classes and shoreline positions will also follow

BICM methodologies.

Geotechnical and Sediment Properties: Grab samples or push cores will be collected at 7

locations along 5 cross-shore transects; back-barrier marsh, dune, berm, mean low water, depth

approximately one third of depth of closure, depth approximately two thirds of depth of closure

and depth of closure. The long-shore spacing of sediment transects will be consistent with BICM


sampling techniques. Additional grab samples will be collected within borrow pits to

characterize sediment properties. The samples will be visually described and those with greater

than or equal to 70% sand content will be analyzed to determine sediment characteristics.

Sediment samples will be collected once in pre-construction and five times within the first 10

years post-construction. Data collected will be analyzed to investigate the change in sediment

composition over time. It is expected that the grain size analyses will provide information on

sediment texture for restoration monitoring and planning, coastal processes, and sediment

dispersal patterns to evaluate fill performance as well as to determine the seaward boundary of

the active profile.

4.2.2 Use of Monitoring Results and Analyses

Project monitoring is the responsibility of the Louisiana OCPR and the USACE. However,

because of the need to integrate monitoring for programmatic adaptive management, extensive

interagency coordination is required. A monitoring workgroup, led by the LCA S&T Program

and the USGS, will be responsible for ensuring that project-specific monitoring plans are

technically competent and appropriately integrated within a system-wide assessment and

monitoring plan.

The results of the monitoring program will be communicated to an Assessment Team that will

use the information to assess system responses to management, evaluate overall project

performance, and construct project report cards. Recommended modifications (i.e., adaptation)

of the TBBSR project will be provided as appropriate.

5.0 DATABASE MANAGEMENT

Database management is an important component of the monitoring plan and the overall

adaptive management program. Data collected as part of the monitoring and adaptive

management plans for the LCA projects will be archived as prescribed in the LCA Data

Management Strategic Plan developed for the LCA Science and Technology Office, and further

developed by the LCA S&T Data Management Working Group.

Data collected for LCA with similar data types and collection frequencies as those data collected

under the CRMS program will be managed by the Louisiana Strategic Online Natural Resources

Information System (SONRIS). Pre-existing standard operating procedures built for SONRIS

cover issues such as data upload process and format, quality assurance/quality control, and

public data release. Storage of all other LCA collected data (spatial or non-spatial) will be

handled by the LCA project specific data libraries on LCA.GOV.

Where applicable, Open Geospatial Consortium standards will be used to facilitate data sharing

among interested parties. Data analysis and reporting responsibilities will be shared between

project assessment and adaptive management efforts in order to provide TBBSR project reports

for the LCA Program Management Team.

5.1 Description and Location

The data management plan should identify the computing hardware and any specialized or

custom software used in data management for an adaptive management program. Opportunities

exist to develop either a centralized or distributed data management system. With input from the

LCA Adaptive Management Planning Team, the data managers should determine which

approach best suits the needs of the overall adaptive management program.


Individuals with responsibility for data management activities (data managers) in support of an

adaptive management program should be identified. The data managers should collaborate with

the Adaptive Management Planning Team in developing a data management plan to support the

adaptive management program. The data management plan should be incorporated into the

overall program adaptive management plan, either in the main body of the adaptive management

plan or as an appendix.

5.2 Data Storage and Retrieval

Data standards, quality assurance and quality control procedures and metadata standards will be

prescribed by the Data Management Working Group, and will be complementary with the

CRMS-Wetlands program and SONRIS database. Data will be served using a map services tool,

similar to that currently employed by the CRMS-Wetlands project.

5.3 Analysis, Summarizing, and Reporting

Data analysis and reporting responsibilities will be shared between project and programmatic

adaptive management efforts in order to provide reports for the TBBSR project Assessment

Team, project managers, and decision-makers.

6.0 ASSESSMENT

The assessment phase of the framework compares the results of the monitoring efforts to the

desired project performance measures and/or acceptable risk endpoints (i.e., decision criteria)

that reflect the goals and objectives of the management or restoration action. The assessment

process addresses the frequency and timing for comparison of monitoring results to the selected

measures and endpoints. The nature and format (e.g., qualitative, quantitative) of these

comparisons are defined as part of this phase. The resulting methods for assessment should be

documented as part of the overall adaptive management plan.

The results of the TBBSR project monitoring program will be regularly assessed in relation to

the desired project outcomes as described by the previously specified project performance

measures. This assessment process continually measures the progress of the project in relation to

the stated project goals and objectives and is critical to the projects adaptive management

program. The assessments will continue through the life of the project or until it is decided that

the project has successfully achieved (or cannot achieve) its goals and objectives.

6.1 Assessment Process

The Assessment Team assigned to the TBBSR project will identify a combination of qualitative

(i.e., professional judgment) and quantitative methods for comparing the values of the

performance measures produced by monitoring with the selected values of these measures that

define criteria for decision-making.

Appropriate statistical comparisons (e.g., hypothesis testing, ANOVA, multivariate methods,

etc.) will be used to summarize monitoring data and compare these data with the TBBSR project

decision criteria. These continued assessments will be documented as part of the project

reporting and data management system.

6.2 Variances and Success

The project Assessment Team will collaborate with project managers and decision-makers to

define magnitudes of difference (e.g., statistical differences, significance levels) between the


values of monitored performance measures and the desired values (i.e., decision criteria) that will

constitute variances. Meaningful comparisons between monitoring results and desired

performance will require characterization of historical and current spatial-temporal variability

that define baseline conditions. Variances (or their absence) will be used to recommend adaptive

management actions, including (1) continuation of the project without modification, (2)

modification of the project within original design specifications, (3) development of new

alternatives, or (4) successful close-out of the TBBSR project.

Conceptual models have been developed for each project describing the linkages between

stressors and performance measures. The assessments will help determine if the observed

responses are linked to the project. Each project has been formulated to address as many system

stressors as feasible. If the stressors targeted by the project have changed and the performance

measure has not, the linkages in the conceptual model should be examined to determine what

other factors may be influencing the performance measure response.

The assessments will also determine if the responses are undesirable (e.g., are moving away from

restoration goals) and if the responses have met the success criteria for the project. If

performance measures are not responding as desired because the stressor has not changed

enough in the desired direction, then recommendations should be made concerning modifications

to the project. If the stressor has changed as expected/desired and the performance measure has

not, additional research may be necessary to understand why.

From a system-wide perspective, scientific and technical information would be generated from

the implementation of a systemwide monitoring effort. Information generated from this effort

should be linked to evaluation LCA performance and system response. From a project-level

perspective, monitoring plans should be designed to inform adaptive management decision

making by providing monitoring data that are relevant to addressing uncertainty.

Similarly, for given multiple performance measures and corresponding monitoring results, the

Assessment Team will determine the number and magnitude of variances within a single

assessment that will be required to recommend modifications to the TBBSR project.

6.3 Frequency of Assessments

Ideally, the frequency of assessments for the TBBSR project would be determined by the

relevant ecological scales of each performance measure. The projects technical support staff

will identify for each performance measure the appropriate timescale for assessment. The project

should have a combination of short-, medium-, and long-term performance measures.

Assessments should be performed at a five year interval at a minimum; however, depending on

the timescale of expected responses of the specific measure and frequency of data collection, it

may be determined during PED that more frequent reporting may be necessary.

6.4 Documentation and Reporting

The Assessment Team will document each of the performed assessments and communicate the

results of its deliberations to the managers and decision-makers designated for the TBBSR

project. The Assessment Team will work with the project monitoring team and monitoring

workgroup to produce periodic reports that will measure progress towards project goals and

objectives as characterized by the selected performance measures. The results of the assessments

will be communicated regularly to the project managers and decision-makers.


7.0 DECISION-MAKING

Adaptive management is distinguished from more traditional monitoring in part through

implementation of an organized, coherent, and documented decision process. For the TBBSR

Adaptive Management program, the decision process includes (1) anticipation of the kinds of

management decisions that are possible within the original project design, (2) specification of

values of performance measures that will be used as decision-criteria, (3) establishment of a

consensus approach to decision making, and (4) a mechanism to document, report, and archive

decisions made during the timeframe of the Adaptive Management Program.

7.1 Decision Criteria

Decision criteria, also referred to as adaptive management triggers, are used to determine if and

when adaptive management opportunities should be implemented. These criteria are usually

ranges of expected and/or desirable outcomes. They can be qualitative or quantitative based on

the nature of the performance measure and the level of information necessary to make a decision.

Desired outcomes can be based on reference sites, predicted values, or comparison to historic

conditions. A potential decision criterion is identified below, based on the project objectives and

performance measures. More specific decision criteria will be developed during the preconstruction engineering and design phase of the project.

Aerial photography for habitat classification and shoreline position. This indicator can detect

increased shoreline erosion on adjacent islands due to implementation of hardened structures,

and the effect from a higher frequency and intensity of storm events than predicted.

Compare pre-project vegetation coverage (in acres) with vegetation coverage five years

after construction to determine if vegetation is propagating as predicted;

Compare vegetation coverage at year five (as a percentage of the total island acreage)

with vegetation coverage (as a percentage of the total island acreage) after year five to

determine if the proper habitat conditions are being maintained;

Compare pre-construction land loss rates to post-construction land loss rates.

To effectively implement adaptive management, predicted outcomes from modeling may need to

be revisited and recalibrated in the light of field observations and field data, so that the Adaptive

Management Planning Team can develop appropriate recommendations for changes. Additional

modeling might be required to understand and manage observed island responses. An adaptive

management action should include incorporation of findings into future island design templates.

7.2 Potential Adaptive Management Measures

The project report card, drafted by the Assessment Team, will be used to evaluate project status

and adaptive management needs. The Assessment Team may submit recommendations for

adaptive management actions to the Adaptive Management Planning Team. The Adaptive

Management Planning Team will investigate and further refine adaptive management

recommendations and present them to the Program Management Team. Some potential adaptive

management actions for this project may include additional vegetative plantings and/or sand

fencing, supplementing original project features with additional sediments to create more beach,

dune and marsh, and the addition and/or removal of structural restoration measures such as

breakwaters or terminal groins.


7.3 Project Close-Out

Close-out of the project would occur when it is determined that the project has been successful or

when the maximum ten year monitoring period has been reached. Success would be considered

to have been achieved when project objectives have been met or when it is clear that they will be

met based upon the trend for the site conditions and processes. Project success would be based

on the following:

Decline in current trend in conversion of beach and marsh to open water

Increase in elevation

Reduction in duration of flooding and tidal prism

There may be issues related to the sustainability of the project that would require some

monitoring and management beyond achieving the project objectives. Due to variable nature of

the Louisiana coastal zone, the monitoring baseline may change during the period of analysis.

Consequently, it may be appropriate to consider extending project-specific monitoring and

adaptive management beyond ten years.

8.0 COSTS FOR IMPLEMENTATION OF MONITORING AND

ADAPTIVE MANAGEMENT PROGRAMS

The costs associated with implementing these monitoring and adaptive management plans were

estimated based on currently available data and information developed during plan formulation

as part of the feasibility study. Because uncertainties remain as to the exact project features,

monitoring elements, and adaptive management opportunities, the costs estimated in Tables 1, 2,

and 3 (below) will be need to be refined in the PED phase during the development of the detailed

monitoring and adaptive management plans.

Costs were estimated based on monitoring concentrated on each of the four islands for one year

during PED and three years post-construction, and seven years of system -level monitoring

through the Barrier Island Comprehensive Monitoring (BICM) Program for determining impacts

on the entire Terrebonne Basin Barrier Shoreline system. The total cost for implementing the

monitoring and adaptive management programs is $10,995,000.*

* This total cost represents a correction from the previously provided cost of $10,595,000.

8.1 Costs for Implementation of Monitoring Program

Costs to be incurred during the PED and construction phases include drafting of the detailed

monitoring plan, monitoring site establishment and pre-construction and construction data

acquisition to establish baseline conditions. Cost calculations for post-construction monitoring

are displayed as a ten-year (maximum) total. If ecological success is determined earlier (prior to

ten years post-construction), the monitoring program will cease and costs will decrease

accordingly.

It is intended that monitoring conducted under the LCA program will utilize centralized data

management, data analysis, and reporting functions. All data collection activities follow

consistent and standardized processes regardless of the organization responsible for monitoring.

Cost estimates include monitoring equipment, monitoring station establishment, data collection,

quality assurance/quality control, data analysis, assessment, and reporting for the proposed

monitoring elements (Table 1). These estimates account for a 2.6% annual inflation rate, adopted


from the CWPPRA Program. The current total estimate for implementing the monitoring

program is $9,315,000. Unless otherwise noted, costs will begin at the onset of the PED phase

and will be budgeted as construction costs.

Table 1. Preliminary Cost Estimates for Implementation of the Monitoring Program for

the LCA Terrebonne Basin Barrier Shoreline Restoration Project.

8.2 Costs for Implementation of Adaptive Management Program

Costs for the project adaptive management program were based on estimated level of effort. The

current total estimate for implementing the adaptive management program is $1,680,000. Unless

otherwise noted, costs will begin at the onset of the PED phase and will be budgeted as

construction costs.

Category Activities PED Data

Acquisition 10 yr Total

Monitoring:

planning and

management

Monitoring

workgroup, drafting

detailed monitoring

plan, working with

PDTs on

performance

measures $195,000

Monitoring:

data

collection

Landrights, site

construction, and

surveying

$83,600

$83,600

Bathymetry/

Topography $1,845,000 $5,636,400

Habitat Mapping $446,700 $1,500,000

Sediment Sampling $446,000 $1,500,000

Database

Management

Database

development,

management, and

maintenance,

Webpage

development for

communication of

data to stakeholders

$167,500

$400,000

TOTAL $2,988,800 $9,315,000


Table 2. Preliminary Cost Estimates for Set-up of Adaptive Management Program for the

LCA Terrebonne Basin Barrier Shoreline Restoration Project.

Category Annual

Cost 4 yr Total

Detailed Adaptive Management Plan

and Program Set-up

(During PED and construction)

$100,000 $400,000

TOTAL $100,000 $400,000

Table 3. Preliminary Cost Estimates for Implementation of Adaptive Management

Program for the LCA Terrebonne Basin Barrier Shoreline Restoration Project.

Category Annual

Cost 10 yr Total

Management of AM Program (Post

Construction) $50,000 $500,000

Assessment $47,000 $470,000

Decision Making $31,000 $310,000

TOTAL $128,000 $1,280,000


9.0 LITERATURE CITED

Fernley, S., L.Brien, L. Martinez, M. Miner, M. Kulp, and S. Penland. 2009. Louisiana Barrier

Island Comprehensive Monitoring Program (BICM) Volume 5: Chenier Plain, South-Central

Louisiana, and Chandeleur Islands, habitat mapping and change analysis  Part 1: Methods for

Habitat Mapping and Change Analysis 1996 to 2005. Prepared for the LA Dept. Natural

Resources, Coastal Restoration Division, Baton Rouge, LA by the Univ. of New Orleans,

Pontchartrain Institute for Environmental Sciences, New Orleans, LA. 11 pp.

Hansen, M., and P. Howd. 2008. Louisiana Barrier Island Comprehensive Monitoring Program

(BICM) Volume 4: Louisiana Light Detection and Ranging Data (LiDAR) - Part 1: LiDAR

systems and data processing techniques. Prepared for the LA Dept. Natural Resources, Coastal

Restoration Division, Baton Rouge, LA by the U.S. Geological Survey Florida Integrated

Science Center. St Petersburg, FL. 23 pp.

Martinez, L., S.O'Brien, M. Bethel, S. Penland, and M. Kulp. 2009. Louisiana Barrier Island

Comprehensive Monitoring Program (BICM) - Volume 2: Shoreline change and barrier island

land loss 1800's-2005. Prepared for the LA Dept. of Natural Resources, Coastal Restoration

Division by the Univ. of New Orleans, Pontchartrain Institute for Environmental Sciences. New

Orleans, LA. 32 pp.

Miner, M., M. Kulp, S. Penland, D. Weathers, J. P. Motti, P. McCarty, M. Brown, L. Martinez, J.

Torres, J. Flocks, N. Dewitt, N. Ferina, B. J. Reynolds, D. Twitchell, W. Baldwin, B. Danforth,

C. Worley, and E. Bergeron. 2009. Louisiana Barrier Island Comprehensive Monitoring Program

(BICM) Volume 3: Bathymetry and Historical Seafloor Change 1869-2007  Part1: South

Central Louisiana and Northern Chandeleur Islands, Bathymetry Methods and Uncertainty

Analysis. Prepared for the LA Dept. Natural Resources, Coastal Restoration Division, Baton

Rouge, LA by the Univ. of New Orleans, Pontchartrain Institute for Environmental Sciences,

New Orleans, LA. 41 pp.

Troutman, J. P., D. M. Lee, S. M. Khalil, B. S. Carter, K. S. Grey, and L. A. Reynolds. 2003.

Proposed Barrier Island Comprehensive Monitoring Program. Louisiana Department of Natural

Resources, Coastal Restoration Division. Baton Rouge, LA. 12 pp.


ANNEX 1. LCA Terrebonne Basin Barrier Shoreline Restoration Project

Conceptual Ecological Model


1.0 INTRODUCTION

1.1 Conceptual Ecological Model Definition

Although the term conceptual ecological model (CEM) may be applied to numerous

disciplines, CEMs are generally simple, qualitative models, represented by a diagram, that

describe general functional relationships among the essential components of an ecosystem.

CEMs typically document and summarize current understanding of, and assumptions about,

ecosystem function. When applied specifically to ecosystem restoration projects, CEMs also

describe how restoration actions propose to alter ecosystem processes or components to improve

system health (Fischenich 2008). To describe ecosystem function, a CEM usually diagrams

relationships between major anthropogenic and natural stressors, biological indicators, and target

ecosystem conditions.

1.2 Purpose and Functions of Conceptual Ecological Models

CEMs can be particularly helpful with the Louisiana Coastal Area (LCA) Program and its

projects by providing assistance with four important tasks: ecosystem simplification,

communication, plan formulation, and science, monitoring and adaptive management.

1.2.1 Ecosystem Simplification

Because natural systems are inherently complex, resource managers must utilize tools that

simplify ecosystem relationships and functions within the target ecosystem. An understanding of

the target ecosystem is paramount to planning and constructing effective ecosystem restoration

projects. During CEM development, known and unknown connections and causalities in the

systems are identified and delineated (Fischenich 2008).

CEMs can promote ecosystem simplification through the following processes:

Organization of existing scientific information;

Clear depiction of system components and interactions;

Promotion of understanding of the ecosystem;

Diagnosis of underlying ecosystem problems;

Isolation of cause and effect relationships; and

Identification of elements most likely to demonstrate an ecosystem response.

1.2.2 Communication

CEMs are an effective tool for the communication of complex ecosystem processes to a large

diverse audience (Fischenich 2008). It is vitally important that project teams understand

ecosystem function in order to realistically predict accomplishments to be achieved by

restoration projects. CEMs can facilitate effective communication between project team

members about ecosystem function, processes, and problems, and can assist in reaching

consensus within the project team on project goals and objectives.

Because CEMs summarize relationships among the important attributes of complex ecosystems,

they can serve as the basis for sound scientific debate. Stakeholder groups, agency functions

(e.g., planning and operations), and technical disciplines typically relate to systems resource use

and management independently, but CEMs can be used to link these perspectives.


The process of model development is at least as valuable as the model itself and affords an

opportunity to draw fresh insight as well as address unique concerns or characteristics for a given

project. Workshops to construct CEMs facilitate brainstorming sessions that explore alternative

ways to compress a complex system into a small set of variables and functions. This interactive

process of system model construction facilitates communication between project team members

and almost always identifies inadequately understood or controversial model components.

CEMs can promote communication by facilitating the following:

Integrating input from multiple sources and informing groups of the ideas, interactions,

and involvement of other groups. (Fischenich 2008);

Assembling project/study managers with the project team and stakeholders to discuss

ecosystem condition, problems, and potential solutions;

Synthesizing current understanding of ecosystem function;

Developing consensus on a working set of hypotheses that explain habitat changes;

Developing consensus on indicators that can reflect project specific ecological

conditions; and

Establishing a shared vocabulary among project participants.

1.2.3 Plan Formulation

Formulating a plan for an effective ecosystem restoration project requires an understanding of

the following elements:

1. The underlying cause(s) of habitat degradation;

2. The manner in which causal mechanisms influence ecosystem components and dynamics;

and

3. The manner in which intervening with a restoration project may reduce the effects of

degradation.

These three elements should form the basis of any CEM applied to project formulation

(Fischenich, 2008).

CEMs can provide valuable assistance to the plan formulation process through the following:

Supporting decision-making by assembling existing applicable science;

Assisting with formulation of project goals and objectives, indicators, management

strategies, and results;

Providing a common framework among team members from which to develop

alternatives;

Supplementing numerical models to assess project benefits and impacts; and

Identifying biological attributes or indicators that should be monitored to best interpret

ecosystem conditions, changes, and trends.

1.2.4 Science, Monitoring and Adaptive Management


Through the recognition of important physical, chemical, or biological processes in an

ecosystem, CEMs identify aspects of the ecosystem that should be measured. Hypotheses about

uncertain relationships or interactions between components may be tested and the model may be

revised through research and/or an adaptive management process. Indicators for this process may

occur at any level of organization, including the landscape, community, population, or genetic

levels; and may be compositional (i.e., referring to the variety of elements in a system), structural

(i.e., referring to the organization or pattern of the system), or functional (i.e., referring to

ecological processes) in nature.

CEMs can be helpful in restoration science, monitoring, and adaptive management through the

following:

Making qualitative predictions of ecosystem response;

Identifying possible system thresholds that can warn when ecological responses may

divergent from the desired effect;

Outlining further restoration and research and/or development needs;

Identifying appropriate monitoring indicators and metrics;

Providing a basis for implementing adaptive management strategies;

Interpreting and tracking changes in project targets;

Summarizing the most important ecosystem descriptors, spatial and temporal scales, and

current and potential threats to the system;

Facilitating open discussion and debate about the nature of the system and important

management issues;

Determining indicators for monitoring;

Helping interpret monitoring results and explore alternative courses of management;

Establishing institutional memory of the ideas that inspired the management and

monitoring plan;

Forecasting and evaluating effects on system integrity, stress, risks, and other changes;

Identifying knowledge gaps and the prioritization of research;

Interpreting and monitoring changes in target indicators; and

Assisting in qualitative predictions and provide a key foundation for the development of

benefits metrics, monitoring plans, and performance measures.

1.2.5 Limitations of Conceptual Ecological Models

CEMs cannot identify the most significant natural resources within the target ecosystem or

prioritize project objectives. They do not directly contribute to the negotiations and trade-offs

common to ecosystem restoration projects. CEMs are not The truth, but are simplified depictions

of reality. They are not Final, but rather provide a flexible framework that evolves as

understanding of the ecosystem increases. CEMs are not Comprehensive because they focus only

upon those components of an ecosystem deemed relevant while ignoring other important (but not

immediately germane) elements. CEMs do not, in and of themselves, quantify restoration


outcomes, but identify indicators that can be monitored to determine responses within the target

ecosystem to restoration outputs.

Good conceptual models effectively communicate which aspects of the ecosystem are essential

to the problem, and distinguish those outside the control of the implementing agency. The best

conceptual models focus on key ecosystem attributes, are relevant, reliable, and practical for the

problem considered, and communicate the message to a wide audience.

1.3 Types of Conceptual Ecological Models

CEMs can be classified according to both their composition and their presentation format. They

can take the form of any combination of narratives, tables, matrices of factors, or box-and-arrow

diagrams. The most common types of CEMs are narrative, tabular, matrix, and various forms of

schematic representations. A comprehensive discussion of these types of CEMs is provided in

Fischenich (2008). Despite the variety in types of CEMs, no single form will be useful in all

circumstances (Fischenich 2008). Therefore, it is of vital importance to establish the specific

plan formulation needs to be addressed by the CEM, and develop the CEM accordingly because

[c]onceptual models . . . are most useful when they are adapted to solve specific problems

(Frischenich 2008).

1.3.1 Application of Conceptual Ecological Models to LCA Projects

CEMs have been widely used in other regions of North America when planning large-scale

restoration projects (Barnes et al., 2005). The LCA team has decided to utilize the Ogden model

(Ogden and Davis, 1999). Like the plan formulation process, the LCA team recognizes that CEM

development is likely to be an iterative process, and that CEMs developed for LCA projects

during early plan formulation may be dramatically changed before project construction.

1.3.2 Model Components

The CEM structure utilized for LCA projects follows the top-down hierarchy of information

using the components established by Ogden and Davis (1999). The schematic organization of the

CEM is depicted in Figure 1 and includes the following components:

Drivers- This component includes major external driving forces that have large-scale

influences on natural systems. Drivers may be natural (e.g., eustatic sea level rise) or

anthropogenic (e.g., hydrologic alteration) in nature.

Ecological Stressors- This component includes physical or chemical changes that occur

within natural systems, which are produced or affected by drivers and are directly

responsible for significant changes in biological components, patterns, and relationships

in natural systems.

Ecological Effects- This component includes biological, physical, or chemical responses

within the natural system that are produced or affected by stressors. CEMs propose

linkages between one or more ecological stressors and ecological effects and attributes to

explain changes that have occurred in ecosystems.

Attributes- This component (also known as indicators or end points) is a frugal subset of

all potential elements or components of natural systems representative of overall

ecological conditions. Attributes may include populations, species, communities, or

chemical processes. Performance measures and restoration objectives are established for

each attribute. Post-project status and trends among attributes are measured by a system-


wide monitoring and assessment program as a means of determining success of a

program in reducing or eliminating adverse effects of stressors.

Performance measures- This component includes specific features of each attribute to be

monitored to determine the degree to which attribute is responding to projects designed to

correct adverse effects of stressors (i.e., to determine success of the project).

Figure 1. Conceptual Ecological Model Schematic Diagram.

This CEM does not attempt to explain all possible relationships or include all possible factors

influencing the performance measure targets within natural systems in the study area. Rather, the

model attempts to simplify ecosystem function by containing only information deemed most

relevant to ecosystem monitoring goals.

2.0 CONCEPTUAL ECOLOGICAL MODEL DEVELOPMENT

2.1 Methodology

A CEM was developed for the Terrebonne Basin Barrier Shoreline Restoration (TBBSR) Project

by members of the interagency Project Delivery Team. The creation of this CEM was an

interactive and iterative process. Prior to model development, the project team reviewed existing

information on the ecosystem within the study area. A small team meeting was then convened to

identify and discuss causal hypotheses that best explain both natural and key anthropogenicallydriven alterations in the study area. A list of appropriate stressors and consequent ecological

effects in the study area ecosystem was developed from these discussions. Additionally, a series

of attributes was identified that exhibited characteristics that ideally suited them to serve as key

indicators of project success through the measurement and analysis of assessment performance

measures associated with these attributes. The project team used these hypotheses and lists of


components to develop an initial draft of the model and to prepare a supporting narrative

document to explain the organization of the model and science supporting the hypotheses.

Additional information about the components of this CEM is presented below.

2.2 Project Background

The TBBSR project was identified as a near-term critical feature in the Louisiana Coastal Area

(LCA) Louisiana - Ecosystem Restoration Study (2004 LCA Plan)(USACE, 2004). The 2004

LCA Plan was recommended to the Congress by a Chief of Engineers report dated January 31,

2005, which recommended a coordinated, feasible solution to the identified critical water

resource problems and opportunities in coastal Louisiana. The TBBSR project was included in

that plan along with other near-term critical restoration features throughout coastal Louisiana.

Including this project, 10 additional projects were recommended for further studies, in

anticipation that such features would be subsequently recommended for future Congressional

authorization. The 2004 LCA Plan was developed by the State of Louisiana and the United

States Army Corps of Engineers (USACE) in order to implement some of the restoration

strategies outlined in the 1998 report Coast 2050: Toward a Sustainable Coastal Louisiana.

The purpose of this study is to investigate the feasibility of simulating historical conditions by

enlarging the barrier islands (width and dune crest) and reducing the current number of breaches.

This Feasibility Study was authorized by the 2004 LCA Plan and the 2007 Water Resources

Development Act (WRDA 2007), which required the completion of a Feasibility Study and the

incorporation of the study findings into a signed Chief of Engineers Report, which must be

submitted to Congress by the Secretary of the Army by December 31, 2010.

This plan incorporated the elements of the previous efforts as well as input from private citizens,

local governments, state and federal agencies, and the scientific community. Unlike the previous

plans, the Coast 2050 Plan took an ecosystem-level approach to coastal restoration. It provided

an overall template for the selection, development and construction of restoration projects and

outlined a set of restoration strategies for restoring south Louisianas wetlands to a sustainable

level. The Coast 2050 Plan evolved into the Louisiana Coastal Area Comprehensive Coastwide

Ecosystem Restoration Study (2004 LCA Plan).

The 2004 LCA Plan began in 2000, building upon the restoration strategies presented in the

Coast 2050 Pplan, and outlined a series of projects that were thought to be necessary to achieve a

sustainable coast. The 2004 LCA Plan serves as the implementation phase for the large-scale

strategies outlined in the Coast 2050 Plan and focuses on large-scale civil works projects that are

beyond the scope and funding level of CWPPRA.

Understanding the critical nature of the land loss situation, a near-term LCA Plan was derived

from the large coastwide study. The Near-Term LCA Plan included a prioritized list of projects

that could be implemented within the next 10 years. The LCA Plan was completed in 2004 and

submitted to Congress. In the Water Resources Development Act of 2007, Congress contingently

authorized six projects, subject to feasibility reports due no later than December 31, 2008.

Included in these projects was the Terrebonne Basin Barrier Shoreline Restoration (TBBSR).

The TBBSR project includes the Isles Dernieres (Raccoon Island, Whiskey Island, Trinity

Island, and East Island) and Timbalier Island (East Timbalier and West Timbalier) Reaches,

which are located in Terrebonne and Lafourche Parishes.

2.2.1 Project Goals and Objectives


The goal of the TBBSR project is to reverse the continuing degradation and deterioration of the

Isles Dernieres (Raccoon Island, Whiskey Island, Trinity Island, East Island, and Wine Island)

and Timbalier Islands (Timbalier Island and East Timbalier Island) in order to achieve a

sustainable coastal ecosystem that can support and protect the environment, economy, and

culture of southern Louisiana and thus the Nation.

The objectives of the project include the following:

Minimize future land loss;

Restore the geomorphic setting of the Isles Dernieres and Timbalier Islands, which are

essential to providing a boundary between the Gulf of Mexico and the Terrebonne

estuary;

Restore and improve various barrier island habitats that provide essential habitat for fish,

migratory birds, other terrestrial and aquatic species;

Protect vital socioeconomic resources including cultures, community, infrastructure,

business and industry, and flood protection features;

Reduce damage from wave energy on interior bays and marshes; and

Maintain and enhance long-shore sediment transport processes.

2.2.2 Project Description

The Project, located in LCA Subprovince 3, provides for the restoration of the Timbalier and

Isles Dernieres barrier island chains located in Terrebonne Parish and Lafourche Parish,

Louisiana. The Project area (Figure 2) is located in the 3rd Congressional District. The barrier

islands projected for restoration are depicted in Figure 2.

The Isles Dernieres Reach represents a barrier island arc approximately 22 miles long in

Terrebonne Parish and extends from Caillou Bay east to Wine Island Pass. Raccoon Island,

Whiskey Island, Trinity Island, and East Island, the primary islands that comprise the Isles

Dernieres barrier island chain (Figure 2), are backed by Bay Blanc, Bay Round, Caillou Bay, and

Terrebonne Bay, and bordered by the Gulf of Mexico (GOM) on the seaward side.

The Timbalier Reach is comprised of Timbalier Island and East Timbalier Island. Timbalier and

East Timbalier islands are on the western edge of the Lafourche barrier shoreline and are located

about 60 miles southwest of New Orleans, Louisiana. This barrier island shoreline is

approximately 20 miles long and backed by Terrebonne and Timbalier Bay to the north and

delimited by Raccoon Pass to the east and Cat Island Pass to the west (Figure 2).

Prior studies have documented degradation of the Terrebonne Basin Barrier Islands and have

demonstrated a need for island restoration. The proposed project involves restoring the islands in

an effort to prevent future land loss where it is predicted to occur, preserving the endangered and

critical geomorphic structure of the islands, and protecting vital local, regional and national

infrastructure.


Figure 2. Terrebonne Basin Barrier Shoreline Restoration Project Study Area

3.0 CONCEPTUAL ECOLOGICAL MODEL DISCUSSION

The CEM developed for the TBBSR Project is presented in Figure 3. Model components are

identified and discussed in the following subsections.

3.1 Drivers

3.1.1 Coastal Processes

The Louisiana coastal zone is one of the most dynamic environments that exist in nature. The

morphology and integrity of that zone, and specifically the Terrebonne Basin barrier island

chain, is directly related to the supply of sediment contributed and the physical processes

operating on the coast of Louisiana. The same processes that built the barrier islands are also

partly responsible for their erosion and fragmentation. The major coastal processes operating to

shape the Terrebonne Basin barrier islands include tides, relative sea-level rise, and long-shore

sediment transport (USACE 2004).

Geologic faulting, compaction of muddy and organic sediment, and sea level change have

shaped the coastal Louisiana landscape for thousands of years (Kulp 2000; Reed 1995). Over

millennia, sea level change and subsidence were offset by delta building in the Deltaic Plain.

Erosion of barrier shorelines and disruption of fragile organic marshes has resulted in land loss,

but also contributed to habitat and wildlife diversity. There is little direct evidence that any of

these natural processes have changed in the mid to late 20th century, therefore it is assumed that

these coastal processes will continue to act as major forcings on Louisianas barrier islands

(USACE 2004).

3.1.2 Atmospheric Processes

Barrier islands form the first line of defense for protecting coastal Louisiana from the direct

effects of wind, waves, and storms. The barrier systems serve multiple purposes to: 1) reduce

coastal flooding during periods of storm surge; 2) prevent direct ocean wave attack, which would

accelerate rates of erosion and degradation of marshes and other wetlands; and 3) help maintain

gradients between saline and freshwater, thereby preserving estuarine systems (USACE 2004).


The Louisiana inner shelf is an example of a low-energy environment where significant

hydrodynamic activity is generated almost exclusively by local storms, including both tropical

(summer) and extratropical (winter) storms. In an average year, 20 to 30 cold fronts will pass

through coastal Louisiana. The resulting response of the coastal waters is the initial increase in

tidal amplitudes, which causes waves to break higher on the beach, overwashing low barrier

islands. Elevated tides increase the flow of ocean water into the bays and marsh systems behind

the barrier islands. As floodwaters reside and exit the inlets with passage of the front, abrupt

changes in wind direction from southerly to northerly cause increased wave heights in the bays.

This continuous process is believed to be responsible for the chronic shoreline erosion behind the

barrier islands.

3.1.3 Anthropogenic Activities

Primary anthropogenic activities that are affecting the project area are oil and gas canals,

extraction of hydrocarbons, navigation canals, and coastal structures. Substantial oil and gas

activity and infrastructure exists on and near the Terrebonne Basin barrier islands, primarily

behind the islands in the Terrebonne and Timbalier bays. Approximately 2,000 Coastal Use

Permits (LDNR 2008a) pertaining to the more than 20 oil and gas fields (LOSCO 2007c), 4,000

injection wells (LOSCO 2007b), 1,100 oil and gas pits (LOSCO 2007d), 110 platform structures

(LOSCO 2007e), and a complex system of pipelines, (LOSCO 2007a) have been issued for these

activities within a 6 mile buffer of the islands.


Figure 3. Conceptual Ecological Model, LCA Terrebonne Basin Barrier Shoreline Restoration Project


11

3.2 Ecological Stressors

3.2.1 Relative Sea-level Rise

The entire Louisiana coastal zone is experiencing relative sea level rise (RSLR). RSLR is

defined here as the net effect of numerous processes that result in the downward displacement of

the land surface relative to sea level. RSLR is controlled by several major factors that include

eustatic sea level, geosynclinal downwarping, compaction of Holocene deposits, and faulting.

Recent studies have shown that anthropogenic activities (subsurface fluid withdrawal) may be a

contributor to RSLR (Morton et al. 2002), however the relative role of the natural and

anthropogenic factors on net regional subsidence has not been well established, despite their

potentially significant influence on coastal erosion patterns and sedimentation processes. Each

process produces a range of subsidence rates dependent on local environmental factors and each

process occurs across a unique set of scale (Reed and Yuill 2009). Changes in land elevation

vary spatially along coastal Louisiana, however in areas where subsidence is high and riverine

influence is minor or virtually nonexistent, such as in areas of western Barataria Basin and

eastern Terrebonne Basin, wetland habitats sink and convert to open water.

Within the TBBSR project area, increased subsidence is a physical response to the lack of

riverine input and the resulting loss of sediments and decreased productivity in vegetation

communities. Subsidence, along with rising sea level, is also largely responsible for shoreline

erosion and the transgressive nature of most of the barrier islands. Estimated subsidence rates for

the Deltaic Plain are between 0.5 to 4.3 ft/century. Factoring in changes in land elevation and

water levels, the average rate of relative sea level change along coastal Louisiana is currently

estimated to be between 3.4 to 3.9 ft/century, and a rate of 0.4 inches per year for the Grand Isle

area (USACE 2004). These are the highest rates of RSLR along the contiguous United States and

help to explain coastal evolution in Louisiana.

3.2.2 Tides

Tidal currents in Louisiana are relatively small, due to the small tidal amplitude. In the absence

of wind, density effects and barometric pressure gradients, these currents reach magnitudes of

approximately 0.3 to 0.5 ft/s. Estimates and observations suggest that tidal currents are stronger

at the surface of the water column and decrease with increasing depth. This occurrence is

primarily due to the encounter of denser and heavier salty gulf waters in deeper regions, which

are less likely to respond to small tide variations. Although small in magnitude in open coastal

waters, tidal currents can reach velocities of approximately 1.7 ft/s at estuary and barrier island

inlets, depending on the inlet dimensions. The amount of circulation attributed to rising and

falling tides or tidal induced circulation is measured as a function of the spatial and temporal

variability of tides along the Louisiana coast. There is a seven-hour lag before high water from

the east coastal zone reaches the west coastal zone, with typical tidal ranges between 1 to 2 feet

depending on the time of month and year.

Normal tides are affected by seasonal weather patterns. In an average year, 20 to 30 cold fronts

will pass through coastal Louisiana. The resulting response of the coastal waters is the initial

increase in tidal amplitudes, which causes waves to break higher on the beach, overwashing low

barrier islands. Elevated tides increase the flow of ocean water into the bays and marsh systems

behind the barrier islands. As floodwaters reside and exit the inlets with passage of the front,

abrupt changes in wind direction from southerly to northerly cause increased wave heights in the

bays. This continuous process is believed to be responsible for the chronic shoreline erosion


12

behind the barrier islands (USACE, 2004c). High tides combined with anthropogenic features

such as canals and spoil banks, can also result in increased flooding durations, which can lead to

soil waterlogging and vegetation stress.

3.2.3 Altered Sediment Transport and Input

Longshore sediment transport is the movement of sediment parallel to the shore. This process is

a result of breaking and shoaling waves suspending sand from the bottom and the displacement

of the sediment down-drift by the longshore current. The magnitude of the longshore current

intensifies with increasing wave height and breaker angle. In addition to these wave parameters,

the rate of transport is a function of beach or barrier orientation, offshore shelf slope, local depth,

shoreline erosion, and sediment deposition and patterns.

Alterations to the natural sediment transport and input systems are largely due to the addition of

manmade structures along the coast. The sand transport system along the Timbalier Basin barrier

islands has been greatly diminished due to the extent of coastal structures in the area. Such as the

jetties at Belle Pass on the western end of the Caminada Headland, which interrupt the natural

flow of sediment, thus reducing the volume transported drown drift. Additionally, the potential

for transferring sand from the Caminada Moreau headland to the Timbalier islands is minimal,

given the large width of Raccoon Pass and the net landward transport of sand to its flood tidal

delta. (CEC and SJB, 2008).

3.2.4 Storms

The Gulf Coast region is affected by tropical and extra-tropical storms. These atmospherically

driven storm events can directly and indirectly contribute to coastal land loss through a variety of

ways: 1) erosion and breaches from increased wave energies; 2) removal and/or scouring of

vegetation from storm surges; and 3) storm induced saltwater intrusion into interior wetlands.

These destructive processes can result in the loss and degradation of large areas of coastal

habitats in relatively short periods of time (days and weeks versus years). Since 1893, over 130

tropical storms and hurricanes have struck or indirectly impacted Louisianas coastline. On

average, a tropical storm or hurricane affects Louisiana every 1.2 years. During the past 100

years, over 50 hurricanes and tropical storms have made landfall along the Louisiana coast with

the highest incidence occurring in September (USACE, 2004a).

In 2005 and 2008 four hurricanes of unprecedented nature, Katrina, Rita, Gustav, and Ike

devastated coastal Louisiana and impacted the entire nation. Specific to the Terrebonne Basin,

the four hurricanes impacted the barrier islands, resulting in gulf shoreline erosion, overwash

from beach/dune habitats to back-barrier habitats, land loss, and damage to oil and gas

infrastructure.

3.2.5 Wind and Wave Activity

Wind can induce circulation in the form of set-up and set-down, seiche, and wind-waves.

Similarly, the presence of front-like weather during the winter and storms during hurricane

season enhances these processes by producing dynamic wind conditions. The speed and direction

of these winds shift abruptly, creating strong gusts. Changing wind speed and direction cause the

generation and transformation of waves along the Louisiana coast. Wind and barometric pressure

induced circulation is critical and dominant in back bays, enclosed bays, and lakes, marshes, and

sub-tidal areas. These processes are characterized by extreme water level fluctuations, and are

responsible for a significant amount of the erosion taking place along the Louisiana coast.


13

3.2.6 Oil and Gas Canals

It is estimated that the direct effects (footprint) of canals has resulted in the loss of nearly 29,000

acres of marsh in Louisiana between 1955 and 1978 (Boesch et al. 1994 from Turner and

Cahoon 1988). Besides the direct wetland loss, canals have dramatically altered the natural

hydrology of coastal Louisiana and have been linked to significant indirect wetland loss in some

areas. On barrier islands, canals can form sediment sinks and alter the natural barrier island

rollover process by capturing overwashed sands during storm events.

The spoil banks, or piles of dredged material placed adjacent to canals during canal construction,

can alter the natural hydrology of the backbarrier marsh by obstructing the sheet flow of water

across the marsh and subsurface flow of water through the marsh. These barriers can result in

prolonged flooding events, especially following storms. Impoundments or semi-impoundments

created by the configuration of several spoil banks have been shown to reduce the frequency and

increase the duration of flooding during tidal events. Prolonged flooding of a marsh can lead to

waterlogged soils, stressed vegetation, and eventual marsh loss. The magnitude of these indirect

effects continues to be a source of great controversy and is likely to vary by location, marsh and

soil types, and level of pre-existing disturbance, among other variables.

3.2.7 Oil and Gas Fluid Withdrawal

The production, refinement, and transport of oil and gas have resulted in both short- and longterm negative environmental impacts to coastal Louisiana. Recent findings have indicated that

oil and gas fluid withdrawal has resulted in regional subsidence and fault reactivation causing

historical wetland losses in south-central Louisiana (Morton et al. 2005). As stressors, induced

subsidence coupled with sea level rise can lead to elevation changes, increased flooding, and

eventual habitat switching and loss.

3.2.8 Navigation Channels

The Terrebonne Basin drainage area encompasses approximately 1,455 square miles. Major

navigation channels within the basin are the Atchafalaya River, Wax Lake Outlet, Houma

Navigation Canal, Gulf Intracoastal Waterway (GIWW), and Lower Atchafalaya River (LOSCO,

1999). These navigation channels introduce and/or compound marine influences in many of the

interior coastal wetlands and water bodies within the Terrebonne Basin (USACE, 2004a).

The HNC has direct influence on the Terrebonne Basin barrier shoreline as its mouth is situated

in Cat Island Pass at the western end of Timbalier Island. Because of the close proximity of the

canal to the western end of Timbalier Island, consideration must be given to ensure that the canal

dredging does not adversely impact the westerly longshore transport of sand and remove sand

from the barrier island system by serving as an artificial sediment sink. Periodic maintenance

dredging of the HNC also provides an opportunity for the beneficial use of dredged material on

Timbalier Island and Isles Dernieres.

3.2.9 Structures

Many human activities at the coast have interrupted or altered the coastal ecological processes.

Some of these activities are widespread across the coast and can affect large areas. Within the

coastal zone, manmade structures are often constructed to facilitate navigation or provide support

for infrastructure, but can inevitably have long-term negative impacts on coastal ecosystems.

Specific to the barrier islands is the construction of revetments, groins, and jetties, which can all


14

alter long-shore transfer and sediment supply to barrier islands and wetlands, and limit island

migration and the land building process.

3.3 Ecological Effects

3.3.1 Erosion and Land Loss

For barrier shorelines, complex interactions between storm events, longshore sediment supply,

coastal structures, and inlet dynamics contribute to the erosion and migration of beaches, islands,

and cheniers. Barrier islands are important elements of the geomorphic framework of the estuary.

Barrier islands separate the gulf from the back-barrier estuarine environment helping to maintain

the salinity gradients important to estuarine species. As islands erode and are breached, marine

forces are allowed to affect the interior boundaries of the estuaries, thereby accelerating land

loss. Barrier islands also serve as valuable storm buffers protecting communities, industry, and

associated infrastructure from storm surges. Barrier island degradation is a natural process and

represents the latter phase of the deltaic process, as described in section 1 INTRODUCTION.

Marine influences, particularly those associated with tropical storm events, gradually erode and

rework the structure of the islands until they eventually disappear. While the acreage amounts

associated with the loss of barrier islands may not contribute appreciably to the total acreage of

land loss in the study area, their disappearance can result in significant and profound impacts on

coastal land loss and ecosystem sustainability. Barrier islands serve as natural storm protective

buffers and provide protection and limit erosion of Louisianas coastal wetlands, bays, and

estuaries, by reducing wave energies at the margins of coastal wetlands. In addition, barrier

islands limit storm surge heights and retard saltwater intrusion. The historic rates of land loss for

Louisiana's barrier islands are varied, and can average as high as 50 acres per year (20.3 ha per

year), over several decades. Hurricane events can push the rate of land loss to surpass 300 acres

per year (122 ha per year). For example, the Isles Dernieres have decreased in acreage from

approximately 9,000acres (3,645 ha) in the late 1880s to approximately 1,000 acres (405 ha) by

2000 (see Appendix D LOUISIANA GULF SHORELINE RESTORATION REPORT).

It is likely that within the next several years, erosion will accelerate due to the significant number

of breaches, subjecting critical habitats to degradation by wave action and saltwater intrusion.

3.3.2 Duration of Flooding

Oil and gas canals, which were primarily dredged between 1950 and 1980, directly changed land

to open water, and indirectly changed the natural hydrologic processes that are essential to a

healthy coastal ecosystem through increased hydrologic connectivity. Additionally, the resulting

spoil banks create impoundment areas within the marsh, reducing water exchange and increasing

periods of inundation. These increased periods of submersion have detrimental effects on plant

life and productivity. An important element of sustaining land elevations is the ability of the

marsh to receive a fresh supply of sediments through re-suspension during storm passages. Much

like the levee system of the Mississippi River, the spoil banks along oil and gas canals have

limited natures ability to renourish the marsh.

3.3.3 Elevation Change

Scouring caused by storms, coupled with relative sea level rise negatively affect the elevation of

the barrier islands. Factoring in changes in land elevation and water levels, the average rate of

relative sea level change along coastal Louisiana is currently estimated to be between 3.4 to 3.9

ft/century (USACE, 2004a).


15

3.3.4 Habitat Switching and Loss

Salinity, elevation, and inundation are the major driving forces in the distribution of coastal

wetland habitats (Mitsch and Gosselink 2000), although these are modified by other factors

including fertility, herbivory, disturbance and burial (Keddy 2001). Salinity predominantly

drives the change among fresh, intermediate, brackish and saline habitats. Extreme salinities may

lead to conversion of fresh and intermediate marshes to open water (Flynn et al. 1995). The

salinity stress on a habitat may be worsened with inundation stress. At higher inundation levels,

the salinity tolerance of the vegetation is lower, subjecting critical habitat to increased the

likelihood of switching or loss, (LDNR, 2003)

Specific to the barrier island system, the aforementioned destructive processes and stressors can

result in the loss and degradation of large areas of coastal habitats in a relatively short period of

time (days and weeks versus years). As the number of breaches increases, erosion will

accelerate, further subjecting critical habitats to degradation by wave action and saltwater

intrusion.

3.3.5 Direct Land Loss

Large-scale conversion of barrier island habitat to open water occurs during hurricane events

when breaches are formed and the island is overwashed exposing the underlying soft muddy

substrates. Direct conversion has also occurred when canals were dredged. In addition to the

direct loss of habitat, canals also leave the island more susceptible to breaching during storm

events.

3.3.6 Sediment Sink

Navigation channels and oil and gas canals can disrupt the natural longshore sediment transport

and barrier island rollover processes. The HNC which is located at the western end of Timbalier

Island was constructed in 1962 and has a maintained depth of 18.8 feet NGVD. Between 1976

and 1990, all of the dredged material removed during routine maintenance of Cat Island Pass was

placed in an Ocean Dredged Material Disposal Site (ODMS) (USACE undated).

Oil and gas location canals, pipeline canals, and canals maintained for recreational access

purposes can also form sediment sinks by trapping sand during overwash events and disrupting

the natural barrier island rollover process.

3.3.7 Altered Hydrology

Levees placed along the Mississippi River have altered the natural hydrology of the deltaic plain

and have cut off the source of sediments that formed the barrier islands. Furthermore, thousands

of miles of navigation channels and oil and gas canals in coastal Louisiana have played a major

role in the loss of wetlands and barrier islands. These losses can be attributed to the direct

conversion of barrier island habitats to open water, as well as by the indirect impacts associated

with altered hydrology and saltwater intrusion. The existing and newly constructed oil and gas

canals and the maintenance of navigation channels will continue to facilitate saltwater intrusion

into interior coastal wetlands.

3.3.8 Altered Sediment Transport

The longshore movement of sediment and absence of sand-sized sediment is the principal cause

of the barrier islands instability (USGS 1995). Additionally, longshore currents redistribute the


16

available sand from eroding headlands to the bays north of the barrier islands where they are no

longer accessible to the sediment-starved islands (USGS 1995).

3.4 Attributes and Performance Measures

3.4.1 Habitat Analysis

Habitat has been identified as a key indicator of project success with respect to preventing

habitat conversion and future land loss. Comparison of pre-project habitat characteristics with

post-project habitat characteristics would serve to determine if the current trend in conversion of

beach and marsh to open water within the study area has declined.

Spatial analyses of habitat and extent have been identified as assessment performance

measures for the determination of the response of habitat to the proposed project. Spatial

analysis may involve comparative analysis of pre-project and post-project aerial or

satellite imagery and may utilize thematic mapper analysis to determine relative changes

in habitat within the study area.

3.4.2 Aerial Extent

Aerial extent has been identified as a key indicator of project success with respect to preventing

future land loss. Comparison of pre- and post-project aerial extent would serve to determine if

the current trend in conversion of land to open water within the study area has declined.

The collapsing of previously described habitat inventory would act as a surrogate, and

suffice for determining the sub-aerial extent of the Terrebonne Basin Barrier Islands.

These datasets would be used to determine relative changes in aerial extent of the barrier

islands within the study area.

3.4.3 Tidal Records

Hydroperiod in the study area has been identified as a key indicator of project success with

respect to reducing hydrologic connectivity between the Gulf of Mexico and the back barrier

bays and interior marsh. Comparison of pre-project and post-project hydrography would serve to

determine if closure of breaches and restoration of the islands have reduced the duration of

flooding and the tidal prism. Two assessment performance measures have been identified for this

attribute, flood duration, and tidal range and variability.

Flood duration has been identified as an assessment performance measure for the

determination of the response of hydrology to the proposed project. This measure may be

obtained from existing water level gauges.

Tidal range and variability have been identified as an assessment performance measure

for the determination of the hydrologic response to the proposed project. These measures

may be obtained by using existing and future tidal records.

3.4.4 Elevation

Topographic surveys will be conducted along pre-determined transects by a professional survey

crew prior to and immediately following construction. Post-construction topographic surveys

will be conducted to document the horizontal and vertical change at the project area.

Elevation has been identified as a key indicator of project success with respect to reducing or

reversing subsidence within the study area. Comparison of pre-project elevation levels with post-


17

project elevation levels would serve to determine if sediment input and soil accretion is occurring

within the study area in response to project features. A post-project increase in elevation would

indicate the introduction and stabilization of sediment onto the islands as a result of the project.

The assessment performance measure that has been identified for this attribute is the BICM

topography.

4.0 LITERATURE CITED

Barnes, T.K., and F.J. Mazzotti. 2005. Using Conceptual Models to Select Ecological Indicators

for Monitoring. Restoration and Management of Estuarine Ecosystems. In: S.A. Bortone (ed.)

Estuarine Indicators, CRC Press, Boca Raton, FL.

Barras, J.A., P.E. Bourgeois, and L.R. Handley. 1994. Land loss in coastal Louisiana, 1956-

1990. National Biological Survey, National Wetlands Research Center Open File Report 94-01.

Lafayette, LA.

Boesch, D.F., M.N. Josselyn, A.J. Mehta, J.T. Morris, W.K. Nuttle, C.A. Simenstad, and D.J.P.

Swift. 1994. Scientific Assessment of Coastal Wetland loss, Restoration and Management in

Louisiana. Journal of Coastal Research Special Issue. No. 20. 103 p.

Fischenich, J.C. 2008. The Application of Conceptual Models to Ecosystem Restoration.

Engineer Research and Development Center Publication TN-EMRRP-EBA-01. U.S. ArmyCorps

of Engineers, Vicksburg District, Vicksburg, MS.

Lee, D. and Syed Khalil. 2007. Unpublished report prepared for presentation at the Houma

Navigation Canal deepening HET meeting on July 24, 2007. Louisiana Department of Natural

Resources, Baton Rouge, Louisiana.

Morton, R.A., J.C. Bernier, J.A. Barras, and N.F. Ferina. 2005, Rapid Subsidence and Historical

Wetland Loss in the Mississippi Delta Plain: Likely Causes and Future Implications: Open-File

Report 2005-1216, U.S. Department of the Interior, U.S. Geological Survey.

Mossa, Joann, S. Penland, and T.F. Moslow. 1985. Coastal Geology Technical Report No. 1.

Coastal Structures in Louisianas Barataria Bight. Louisiana Geological Survey. Baton Rouge,

Louisiana.

Ogden, J.C., and S.M. Davis. 1999. The Use of Conceptual Ecological Landscape Models as

Planning Tools for the South Florida Ecosystem Restoration Programs. South Florida

WaterManagement District, West Palm Beach, FL.

Reed, D.J., and B. Yuill. 2009. Synthesizing and Communicating Subsidence Rates in Coastal

Louisiana: Technical Synthesis Report. University of New Orleans  prepared for the Louisiana

Coastal Area Science and Technology Program.

Turner, R.E., and D.R. Cahoon (eds). 1988. Causes of wetland loss in the coastal central Gulf of

Mexico. Volume 1: Executive Summary. OCS Study MMS 87-0120, Final report submitted to

Minerals Management Service, New Orleans, Louisiana, under MMS Cooperative Agreement

14-12-0001-30252.

U.S. Army Corps of Engineers. 2004. Louisiana Coastal Area (LCA) Ecosystem Restoration

Study. Volume 4: LCA Study  Main Report. November, 2004.

U.S. Army Corps of Engineers. Undated. Houma Navigation Canal, Louisisiana. Site

Management Plan for the Maintenance Dredging Ocean Dredged Material Disposal Site.


18

U.S. Geological Survey. 1995. Louisianas Barrier Islands: A Vanishing Resource. Selected

Issue in the USGS Marine and Coastal Geology Program. USGS, Quissett Campus, Woods Hole,

MA.



APPENDIX J

REAL ESTATE PLAN



Appendix J

REAL ESTATE PLAN

Terrebonne Basin Barrier Shoreline Restoration Project

Feasibility Study

Terrebonne Parish, Louisiana

NER Plan

September 22, 2010


2

Real Estate Plan

Terrebonne Basin Barrier Shoreline Restoration Project

Feasibility Study

Table of Contents

PURPOSE:..................................................................................................................................3

PROJECT LOCATION:...........................................................................................................3

PROJECT SPONSOR:..............................................................................................................4

GENERAL PROJECT DESCRIPTION FOR THE NER PLAN:........................................4

LER: ..........................................................................................................................................12

NFS OWNED LER ..................................................................................................................13

ESTATES..................................................................................................................................13

SPONSOR LAND ACQUISITION CAPABILITY:.............................................................14

ACQUISITION COSTS:.........................................................................................................15

ACQUISITION SCHEDULE: ................................................................................................15

RELOCATION ASSISTANCE BENEFITS: ........................................................................15

ENVIRONMENTAL ISSUES: ...............................................................................................16

STATE/FEDERAL PROJECTS IN THE PROJECT AREA: ............................................16

FEDERALLY OWNED LANDS:...........................................................................................19

MINERAL EXPLORATION: ................................................................................................19

INDUCED FLOODING:.........................................................................................................20

ZONING ORDINANCES: ......................................................................................................20

FACILITY/UTILITY RELOCATIONS: ..............................................................................20

NAVIGATION SERVITUDE:................................................................................................21

ACQUISITION PRIOR TO PPA:..........................................................................................22

LANDOWNER ATTITUDE:..................................................................................................22

Table of Exhibits

Exhibit I: Non-Federal Sponsor Assessment of Acquisition Capability

Exhibit II: Chart of Accounts

Exhibit III: Quality Control Plan Checklist

Exhibit IV: Sample Letter Agreement Between Agencies

Exhibit V: Sample State of Louisiana Right- of-Way Grant

Exhibit VI: Timbalier Facility/Utility Maps

Exhibit VII: Request to Deviate from Acquisition of Fee Interest


3

Purpose:

The purpose of this Real Estate Plan is to determine the impact of the proposed construction

on the real estate located within the project limits. This Real Estate Plan (REP) presents a

preliminary plan for any acquisitions of lands, easements, relocations and rights-of-way

necessary for construction and implementation of the National Ecosystem Restoration (NER)

Plan outlined in the, Terrebonne Basin Barrier Shoreline Restoration in Terrebonne Parish,

Louisiana. However, the NER plan cannot be constructed within the maximum project cost

as authorized by WRDA 2007 and modified according to section 902 of the WRDA 1986, as

amended. Therefore, Alternative 11, a subset of the NER plan, is the implementable part of

the NER Plan within the current authorization. The construction and renourishment of

Whiskey Island is the first component of construction of the NER Plan. Because USACE will

seek additional authorization in order to construct additional increments of the NER plan, this

REP addresses the entire NER plan. This document is for planning purposes only and is

subject to change.

Project Location:

The Louisiana Coastal Authority (LCA) study area, which includes the Louisiana coastal area

from Mississippi to Texas, is comprised of two wetland-dominated ecosystems, the Deltaic

Plain of the Mississippi River and the closely linked Chenier Plain, both of which are

influenced by the Mississippi River. For planning purposes, the LCA study area was divided

into four subprovinces, with the Deltaic Plain comprising Subprovinces 1, 2, and 3, and the

Chenier Plain comprising Subprovince 4. The Terrebonne Basin Barrier Shoreline Restoration

Project, recommends the construction of the NER plan, which involves ecosystem restoration

of Whiskey Island, Trinity Island, Raccoon Island, and Timbalier Island in Terrebonne Parish.

Figure 1: Terrebonne Basin Barrier Shoreline Restoration Study Area


4

Project Sponsor:

The Non-Federal Sponsor (NFS) is the Coastal Protection and Restoration Authority (CPRA),

an agency of the State of Louisiana. However the Office of Coastal Protection and Restoration

(OCPR), (also a State of Louisiana agency), is the implementing arm of CPRA, which has

been given authority to acquire and hold these lands. As the Non-Federal Sponsor, CPRA

through OCPR must provide all real estate interests required for this proposed project

construction, i.e., all lands, easements, right-of-way relocations, and any other interests,

including suitable borrow and dredged or excavated material disposal areas (LERRDs). OCPR

has indicated it would provide all lands, water bodies, and/or water bottoms that are owned,

claimed, or controlled by the State of Louisiana. If condemnation becomes necessary OCPR,

having no quick take authority of its own, will partner with another public agency to acquire

the lands needed for this project. The NFS feels confident in being able to meet the public

need requirements of the quick take statutes of the State of Louisiana.

General Project Description for the NER Plan:

The NER plan was selected because it represents a system-wide and cost-effective approach of

restoring as many islands within the Terrebonne Basin barrier system which can be

constructed with available sediment sources. A renourishment plan was also developed for the

islands to maintain their geomorphologic form and ecologic function throughout the 50-year

period of analysis.

Alternative 5 (Raccoon with Terminal Groin (Plan E) / Whiskey (Plan C) / Trinity (Plan C) /

and Timbalier (Plan E)) was selected as the NER because it is a Best Buy plan that fulfills the

planning objectives of this study. The alternative restores the geomorphologic form and

ecologic function of the four islands in the Terrebonne Basin barrier system. Immediately

after construction, the NER will add 3,283 acres of habitat (dune, intertidal, and supratidal) to

the existing island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing

the total size of the islands to 5,840 acres. This includes approximately 472 acres of dune,

4,320 acres of supratidal habitat, and 1,048 acres of intertidal habitat. In addition to protecting

and maintaining precious ecological benefits, the NER protects existing State investments on

the island.

The NER plan will require approximately 27.3 million cubic yards (mcy) of beach material

and 18.7 mcy of marsh material for initial construction. This material will be dredged from a

number of offshore borrow areas including South Pelto, Whiskey 3, New Cut, Raccoon, and

Ship Shoal (all state or federally owned waterbottoms). Therefore, no borrow easement is

necessary; the State of Louisiana will issue a Grant of Particular Use (GPU) or a Letter

Agreement , such as the sample one shown in Exhibit IV, between governmental agencies to

cover project features for the construction of this project. Appropriate permitting will be

obtained from the Mineral Management Service (MMS) prior to mining operations in federal

waters.

Following are brief descriptions of the work to be completed on each of the islands in the NER

plan.


5

Whiskey (Plan C)

Whiskey Plan C proposes approximately 622 acres of beach/dune and 110 acres of marsh will

be created, resulting in a total of 732 acres.

Whiskey Plan C was designed to avoid impacts to approximately 286 acres of existing

mangroves on the island in order to minimize the ecologic impact during construction. Plan C

was also designed to complement TE-50, which is an existing CWPPRA project that was

constructed in 2009. TE-50 created approximately 316 acres of intertidal back-barrier marsh

between the two existing mangrove stands.

Fill quantities for the dune/beach and marsh components of Whiskey Plan C are 8.3 million

and 0.6 million cubic yards, respectively. For the dune area, the material will be pumped from

the dredge to the beach. The material will then be worked on the beach by bulldozers and

front-end loaders. For the marsh area, the material will be pumped from the offshore borrow

site. Dikes will be constructed around the perimeter. These operations will be completed in a

manner that will minimize turbidity of the water at the dredge site and the discharge site.

Approximately 18,075 feet of sand fencing will be installed. The sand fences are porous

barriers that reduce wind speed along the coast such that sand being transported by the wind

accumulates on the downwind side of the fence. The sand fences will promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach visitors,

and protect vegetative plantings. Vegetative plantings will include a variety of native species.

Raccoon with Terminal Groin (Plan E)

Raccoon Plan E proposes approximately 360 acres of beach/dune and 318 acres of marsh will

be created, resulting in a total of 678 acres.

Eight detached and segmented breakwaters were constructed as part of a CWPPRA project

(TE-29) in 1997. The breakwaters were installed to reduce shoreline retreat, promote sediment

deposition along the beach, and to protect seabird habitat. Due to the success of the TE-29

breakwaters, eight additional breakwaters were constructed as part of a separate CWPPRA

project (TE-48) that was completed in 1997. The breakwaters were installed west of the

original breakwaters. TE-48 also included the creation of approximately 60 acres of emergent

and intertidal back-barrier marsh. Raccoon Plan E was designed to complement the intertidal

marsh created as part of TE-48. Plan E was also designed to avoid approximately 58 acres of

existing mangroves immediately adjacent to and gulfward of TE-48.

A terminal groin will also be constructed as part of Raccoon Island Plan E. The terminal groin

will be approximately 1200 feet long and 75 feet wide and will be installed at the western

terminus of the template to prevent sediment migration out of the Isle Dernieres system.

Fill quantities for the dune/beach and marsh components of Raccoon Plan E are 5.2 million

and 5.1 million cubic yards, respectively. For the dune area, the material will be pumped from

the dredge to the beach. The material will then be worked on the beach by bulldozers and

front-end loaders. For the marsh area, the material will be pumped from the offshore borrow

site. Dikes will be constructed around the perimeter. These operations will be completed in a

manner that will minimize turbidity of the water at the dredge site and the discharge site.


6

Approximately 11,912 feet of sand fencing will be installed. The sand fences are porous

barriers that reduce wind speed along the coast such that sand being transported by the wind

accumulates on the downwind side of the fence. The sand fences will promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach visitors,

and protect vegetative plantings. Vegetative plantings will include a variety of native species.

Timbalier (Plan E)

Timbalier Plan E proposes approximately 1567 acres of beach/dune and 1063 acres of marsh

will be created, resulting in a total of 2630 acres. A 2 acre access channel will be constructed

to allow continued access to a Tennessee Connection facility on the western side of the island.

A 6 acre access channel will be constructed to allow for the continued access to two Hilcorp

facilities within the project footprint. Both access channels will be within state waterbottoms.

See the attached maps in Exhibit VI.

Fill quantities for the dune/beach and marsh components of Timbalier Plan E are 10.7 million

and 9.1 million cubic yards, respectively. For the dune area, the material will be pumped from

the dredge to the beach. The material will then be worked on the beach by bulldozers and

front-end loaders. For the marsh area, the material will be pumped from the offshore borrow

site. Dikes will be constructed around the perimeter. These operations will be completed in a

manner that will minimize turbidity of the water at the dredge site and the discharge site.

Approximately 35,425 feet of sand fencing will be installed. The sand fences are porous

barriers that reduce wind speed along the coast such that sand being transported by the wind

accumulates on the downwind side of the fence. The sand fences will promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach visitors,

and protect vegetative plantings. Vegetative plantings will include a variety of native species.

Trinity (Plan C)

Trinity Plan C proposes approximately 499 acres of beach/dune and 512 acres of marsh will be

created, resulting in a total of 1,011 acres.

Fill quantities for the dune/beach and marsh components of Trinity Plan C are 3.1 million and

4.0 million cubic yards, respectively. For the dune area, the material will be pumped from the

dredge to the beach. The material will then be worked on the beach by bulldozers and frontend loaders. For the marsh area, the material will be pumped from the offshore borrow site.

Dikes will be constructed around the perimeter. These operations will be completed in a

manner that will minimize turbidity of the water at the dredge site and the discharge site.

Approximately 22,467 feet of sand fencing will be installed. The sand fences are porous

barriers that reduce wind speed along the coast such that sand being transported by the wind

accumulates on the downwind side of the fence. The sand fences will promote deposition of

windblown sand, create dune features, reduce trampling of existing dunes by beach visitors,

and protect vegetative plantings. Vegetative plantings will include a variety of native species.


7

Renourishment

Raccoon Island will be renourished at year 30 by adding adequate sediment such that the

dune and supratidal beach acres would be equivalent to that of a newly constructed Plan B

template. Whiskey Island will require two renourishment intervals. The first will occur at

year 20 and will include the addition of the same amount of dune and supratidal beach habitat

that was originally created in year 1. The second renourishment interval will occur at year 40

and will include the addition of the same amount of dune and supratidal beach habitat needed

to construct a Plan B template. Trinity Island will be renourished at year 25 by adding the

same amount of dune and supratidal beach habitat that was originally added in year 1.

Timbalier Island will be renourished at year 30 by adding adequate sediment such that the

dune and supratidal beach habitat acres would be equivalent to the acres of a newly

constructed Plan B template.

Maps of the footprints of each of the islands are as follows:


8


9


10


11


12

LER:

Whiskey Island is an uninhabited island off the coast of Terrebonne Parish. Access to the

Island is only by boat. Based on measurements derived form 2008 aerial imagery, it has a

footprint which contains 855 acres. The island has a narrow beach area on the Gulf front and

broken marsh on the landside. Fill for the dune/beach and marsh components will be placed

directly into waterbottoms owned by the State of Louisiana as well as the upland areas owned by

the State. The island is owned by the State of Louisiana and is under the jurisdiction of the

Louisiana Department of Wildlife & Fisheries for Isles Dernieres Barrier Island Refuge,

therefore, easements are not needed for this island, only a Grant of Particular Use.

Timbalier Island has a footprint which contains approximately 1,087 acres. Existing canals are

apparently routinely used to service isolated petroleum production facilities and wells, based on

evidence of recent dredging. Active gas production is present on the northern side of the island.

The project footprint allows for access to be maintained the active facilities currently being

utilized on the north side of the Island. Exhibit VI contains maps depicting the locations of the

facilities and wells. Fill for the dune/beach and marsh components will be placed directly into

waterbottoms owned by the State of Louisiana as well as the upland areas owned by the State

and private entities. The majority of the island is owned by the State of Louisiana, however, one

end of the island has some private ownership, which is estimated to be approximately 80 acres.

The ownership of this land is heavily disputed; however, preliminary data indicates that each of

the 11 estimated tracts contain multiple owners. A Standard Perpetual Beach Nourishment

Easement would be acquired over these 80 acres of private property.

Raccoon Island is owned by the State of Louisiana and is valued highly by LDWF because it is

the largest pelican rookery in Louisiana, critical habitat for Piping Plover, and it is frequented by

other threatened and endangered species. The island has a footprint which contains

approximately 235 acres. Fill for the dune/beach and marsh components will be placed directly

into waterbottoms owned by the State of Louisiana as well as the upland areas owned by the

State. The island is owned by the State of Louisiana and is under the jurisdiction of the

Louisiana Department of Wildlife & Fisheries for Isles Dernieres Barrier Island Refuge,

therefore, easements are not needed for this island, only a Grant of Particular Use.

Trinity Island has a footprint which contains approximately 887 acres. What had been two

islands for decades, and rejoined only recently appears to be successfully maintaining itself. Fill

for the dune/beach and marsh components will be placed directly into waterbottoms owned by

the State of Louisiana as well as the upland areas owned by the State and a private entity. The

majority of the island is owned by the State of Louisiana; however, a small portion of the island,

approximately 30 acres, is privately owned by what appears to be one landowner. A Standard

Perpetual Beach Nourishment Easement would be acquired over these 30 acres of private

property.


13

NFS Owned LER

CPRA, the non-federal sponsor, does not own the land, easements, or rights-of-way (LER)

required for this project. The Louisiana Department of Wildlife and Fisheries (LDWF) owns the

surface rights to Whiskey Island and mineral rights are retained by Louisiana Land and

Exploration (LL&E). The Louisiana Department of Wildlife and Fisheries (LDWF) owns the

surface rights to Raccoon Island and mineral rights are retained by what appears to be one

private landowner. The Louisiana Department of Wildlife and Fisheries (LDWF) owns the

surface rights for the majority of Trinity Island, however, there appears to also be one private

landowner for approximately 30 acres. It appears that this private landowner also owns the

underlying mineral rights. The Louisiana Department of Wildlife and Fisheries (LDWF) owns

the surface rights for the majority of Timbalier Island, however, there appears to be 11 privately

owned tracts as well as private underlying mineral right holders.

Estates

The LDWF owns fee (excluding minerals) for Whiskey Island and Raccoon Island, therefore, the

State has sufficient interests to meet the requirements for these two islands. The LDWF also

owns fee (excluding minerals) for portions of Trinity Island and Timbalier Island. A Grant of

Particular Use (GPU) would be given from the State to USACE for these State-owned areas.

The rights delineated in the GPU will be similar to the language in the following standard and

non-standard estates: Perpetual Beach Nourishment Easement, Perpetual Restrictive Dune

Easement, Temporary Work Area Easement, and a Wetland Creation and Restoration Easement.

The acquisition of these specific estates over these areas is not required because the land is

owned by the State of Louisiana. Therefore, only administrative costs would apply.

For the private property located on Trinity Island and Timbalier Island, easements would need to

be acquired. Project maps for these islands indicate that all marsh creation and dune creation

would take place in state waterbottoms, and that only beach creation and nourishment would

impact private lands. Therefore, the estate anticipated to be acquired would be a Standard

Perpetual Beach Nourishment Easement.

PERPETUAL BEACH NOURISHMENT EASEMENT

A perpetual and assignable easement and right-of-way in, on, over and across (the land described

in Scheudle A) (Tract No. ___) to construct, operate, maintain, patrol, repair, renourish, and

replace the beach berm and appurtenances thereto, including the right to borrow and /or deposit

fill, together with the right to trim, cut, fell and remove therefrom all trees, underbrush,

obstructions, and any other vegetation, structures, or obstacles within the limits of the easement;

reserving, however, to the grantor(s), (his) (her) (its) (their) (heirs,) successors and assigns, all

such rights and privileges as may be used without interfering with or abridging the rights and

easement hereby acquired; subject, however, to existing easements for public roads and

highways, public utilities, railroads and pipelines.

(Standard Estate as set forth in memorandum dated 4 August 1995 signed by Ms. Laura

Ouverson Norman, Chief, Acquisition Division, Directorate of Real Estate.)


14

It is Corps of Engineers policy to acquire fee simple title for ecosystem restoration projects.

Two reasons for such requirement is to reduce the risk that incompatible uses on project land will

occur after project construction, and to ensure that ownership rights vested in the project are

clear and enforceable (ER 1105-2-100, Appendix F, Amendment # 2, F-20b(2)(a). However,

regulations also indicate that a lesser interest, such as, a specific type of permanent easement,

may be appropriate depending upon the operational requirements of the project and other

circumstances relevant to project implementation, including landowner preference (EP 1165-2-

502, 17b). Circumstances wherein the acquisition of interests less than fee may be appropriate is

where only select and easily identifiable and narrow affirmative rights are required for successful

implementation of the project (ER 1105-2-100, Appendix F, Amendment # 2, F-20b(2)(b)i.)

It is the opinion of the Non-Federal Sponsor and the District that construction of this project can

be accomplished through the acquisition of easements rather than fee. The recommended estate

is the Perpetual Beach Nourishment Easement. However, it should be noted that this is a

planning document and the necessary estates are subject to change dependent upon project needs.

It is the opinion of the project delivery team (PDT) that the estate proposed herein provides

sufficient rights to the Government to construct the project and also protect the interests of the

Government. Because the area of private ownership accounts for a small portion of the project

area, there is little risk that activities undertaken by private landowners would adversely impact

the overall benefits of the restoration project. Most of the project area is owned in fee excluding

minerals by the State of Louisiana and regulated as part of the Isles Dernieres Barrier Islands

Refuge. Moreover, due to the topography of the project site, its remote location, its limited

access, and its susceptibility to tropical storms,it is highly unlikely that any private landowners

would propose development. Therefore, the PDT determined that it was unnecessary to acquire

fee or to include specific restrictions on development in the proposed easement. Additionally,

there is little risk that landowners within the area of private ownership would seek to exploit their

underlying mineral rights in a manner that would impact the surface. Under state law, once the

surface erodes into state water bottom and, if applicable, at the termination of mineral leases

protected by the freezing statute, mineral interests become the property of the State. Therefore,

in order to maintain ownership of mineral rights, it is in the best interest of the landowners to

avoid activities that adversely impact the surface. Accordingly, the PDT determined that it was

unnecessary to acquire fee or to include specific restrictions on surface activities in the proposed

easement. An analysis of mineral activity and its potential impact on benefits throughout the

project area can be found on pg. 19.

Please refer to Exhibit VII for the memorandum requesting approval to deviate from acquiring

fee interest for this project.

Sponsor Land Acquisition Capability:

The Non-Federal sponsor for this project is the Coastal Protection and Restoration Authority of

Louisiana (CPRA), through the Office of Coastal Protection and Restoration. As the non-federal

sponsor, CPRA must provide all real estate interests required for the project, i.e., all lands,

easements, rights-of-way, relocations, and any other interest, including suitable borrow and

dredged or excavated material disposal areas (LERRDs).


15

The Non-Federal Sponsor is assessed to be fully capable to perform all acquisition activities

associated with this project. The Sponsor has the capability to acquire and hold real estate as

well as the ability to contract for real estate services to supplement its staff in order to meet

project schedules. However, it must be recognized herein that CPRA is the non-federal sponsor

for all New Orleans District coastal restoration projects and all hurricane risk reduction projects.

Therefore, if all LCA projects and several hurricane risk reduction projects are authorized for

construction under concurrent schedules, there is a possibility that CPRA may not be able to

accomplish LER acquisition due to the massive amount of work required for such an

undertaking. If that were the case, it is possible that CPRA may request that the Federal

Government accomplish acquisition of LER on their behalf.

The Assessment of the Non-Federal Sponsors Real Estate Acquisition Capabilities is attached as

Exhibit I.

Acquisition Costs:

Construction and renourishment of the NER plan will occur on both State owned and private

properties; therefore, costs will be incurred associated with obtaining title, mapping and right of

entry for construction from the State and private ownerships; as well as appraisals, negotiations,

and the actual land costs for the easements over the private property. Costs are estimated to be

approximately $692,000. A chart of accounts is included in Exhibit II.

Acquisition Schedule:

The following schedule is subject to further authorization to construct the NER Plan. Subject to

project approval and funding, the acquisition process will begin after the Project Partnering

Agreement (PPA) is signed. The start date is from the signing of the PPA, but the following

dates are consecutive.

Request for ROE 30 days

Obtain title information 120 days

Obtain mapping information 60 days

Obtain appraisals 120 days

Negotiate & Issue right-of-entry ** 12 months

MMS permits for borrow 12-14 months

These time frames assume amicable acquisitions, if condemnation proceedings are necessary, 12

months may be added to the schedule.

** Negotiations could be necessary for up to 100 owners.

Relocation Assistance Benefits:

The project does not displace residential, commercial or industrial facilities. Therefore, the

provisions of Title II of Public Law 91-646, as amended are not applicable.


16

Environmental Issues:

HTRW:

A Phase I Environmental Site Assessment was conducted of the study area. Based on historical

sources that were researched, environmental database reviews, and aerial site reconnaissance, the

contractor was unable to identify any current or historical recognized environmental conditions

as defined in ASTM Standard E 2247-08. A more in depth site visit and interview with persons

knowledgeable of the site history will be conducted prior to construction of the project.

EMERGENT LANDS:

The Louisiana Land and Exploration Company (LL&E) transferred surface ownership of

Whiskey, Raccoon, and a portion of Trinity/East Island to the State of Louisiana in a July 24,

1997 Act of Donation to create the Isles Dernieres Barrier Islands Refuge. As consideration for

the donation, LL&E retained 50% of the subsurface mineral rights relating to any lands that

emerge from the water bottom. Additionally, LL&E retained a right to use the surface of the

islands for mineral exploration and extraction. The PDT determined that this reservation of

mineral and surface rights would be unlikely to pose a significant risk to the projects benefits.

Surface activities would only be allowed if the appropriate Federal and state agency permissions,

approvals, and permits were acquired. Additionally, as evidenced by existing mineral activity on

the Terrebonne Basin Barrier Islands, the exercise of underlying mineral rights generally does

not require use of the surface and can be accomplished from open water. Therefore, the police

powers in place are considered to protect any emergent lands as a result of the project.

Compensatory Mitigation

No compensatory mitigation is required for this project. As an ecosystem restoration project, the

alternatives were designed to avoid environmental impacts. Any incidental temporary impact

that might be incurred during construction will be more than offset by the net habitat value

created by the project.

Oyster Leases

Active oyster leases exist in this area, however, existing information indicates that oyster leases

will not be directly impacted by the construction and renourishment of the project features.

State / Federal Projects in the Project Area:

Numerous State and Federal plans exist in the project area including Coastal Impact Assistance

Program (CIAP) projects and Coastal Wetland Planning, Protection, and Restoration Act

(CWPPRA) projects.


17

CIAP Projects:

Raccoon Island Breakwaters

East Timbalier Island Sediment Restoration

Wine Island Restoration

Ship Shoal: Whiskey Island West Flank Restoration

Beach and Back Barrier Marsh Restoration, East and Trinity Islands

East Island Beach Dune & Marsh Restoration

East Timbalier Island (Eastern Section) Restoration

East Timbalier Island Restoration


18

CWPPRA Projects:

TE-18 Timbalier Island Plantings Demonstration

TE-20 Isle Dernieres Restoration  East Island

TE-24 Isle Dernieres Restoration  Trinity Island

TE-25 / TE-30 East Timbalier Sediment Restoration  Phases 1 & 2

TE-27 Whiskey Island Restoration

TE-29 Raccoon Island Breakwaters Demonstration

TE-37 New Cut Dune and Marsh Restoration

TE-40 Timbalier Island Dune and Marsh Restoration

TE-47 Ship Shoal: Whiskey West Flank Restoration

TE-48 Raccoon Island Shoreline Protection / Marsh Creation

TE-50 Whiskey Island Back Barrier Marsh Creation

TE-52 West Belle Pass Barrier Headland Restoration

TE-53 Enhancement of Barrier Island Vegetation Demonstration


19

Federally Owned Lands:

There are no federally owned lands in the project right-of-way.

Mineral Exploration:

Throughout the project area, several oil and gas pipelines are present. Pipeline crossings occur

within the island footprints, between the islands, and within the vicinity of the islands inshore

waters. These pipelines are used to transport crude oil and natural gas from wells to facilities

scattered throughout the Terrebonne Basin. These lines will be identified, marked and protected

during construction and renourishment. It has been determined that due to the nature of this

project, the placement of sediment on these lines will pose no adverse impact on the pipelines.

Although the mineral rights underlying the islands surface are privately held, it was determined

that no acquisition of mineral rights was necessary to protect project benefits. As discussed on

pg. 16 in the section on Emergent Lands, the exercise of mineral rights does not appear to require

use of the islands surface. Much of the existing mineral activity in the project area occurs in

open water, and Federal and state regulatory programs are in place to protect the islands from

unacceptable adverse impacts. These programs require that activities be conducted in a manner

that causes the least environmental impact. Accordingly, where an activity can feasibly be

conducted from open water, such alternatives generally would be permitted over alternatives

impacting the surface of the islands.

In addition, the LDWF has established procedures for granting permits for exploratory activities

on its WMAs. These procedures would apply to Whiskey, Raccoon and portions of Trinity/East

Islands, as they are part of the Isles Dernieres Barrier Islands Refuge. Below is a list of

requirements from the LDWF.

The LDWF requires a request for permit be submitted in writing. A Conditions of Letter of

Permission to Conduct Seismic Activity in the State of Louisiana form must be signed by the

company proposing exploration. If the LDWF grants the permit in accordance with regulations,

there are still other actions that must be taken prior to beginning exploration. The seismic

company must request a Natural Heritage review and submit a Notification of Beginning of

Seismic Exploration form. In addition, the company must hold a public meeting. Below are

some additional requirements and restrictions that are typical for LDWF owned and managed

areas:

1. Compensatory mitigation is required to offset unavoidable wetland impacts.

2. No activities will be allowed on emergent islands or vegetated wetlands

3. The company must work closely with LDWF in conducting operations with the purpose of

minimizing any adverse effects and protecting and preserving the fish, birds, animals and

other wildlife, including reefs and oyster beds, in the area.

4. A compliance inspector, with proper qualifications acceptable to LDWF will be funded by

Grantee/Lessee to ensure that the geophysical provisions are met and to provide a weekly email status report to LDWF and a final report of project activities.


20

5. All transportation equipment will require approval of LDWF prior to use

6. The seismic project shall be supervised by a seismic agent or other LDWF representative.

In addition to these regulations in place by the LDWF, any activity in the marshes (wetlands) is

regulated by Section 404 of the Clean Water Act under the purview of the USACE.

Induced Flooding:

This project will not induce flooding.

Zoning Ordinances:

Zoning ordinances will not be enacted in lieu of obtaining letter agreements from the non-federal

entities or easements from private owners.

Facility/Utility Relocations:

There are no relocations associated with construction or renourishment of the project. Only

agreements to allow cover to be put over the existing pipeline crossings in the island footprints

will be necessary.

Throughout the project area, several oil and gas pipelines are present. Pipeline crossings occur

within the island footprints, between the islands, and within the vicinity of the islands inshore

waters. These pipelines are used to transport oil crude and natural gas from wells to facilities

scattered throughout the Terrebonne Basin. There appears to be a total of 12 oil and gas

pipelines within the project area eleven of which are currently active.

Several State and Federal projects have included restoration features that involved placing fill

over existing lines in this project vicinity. For Federal projects, the USACE has obtained a

Letter of No Objection from the pipeline owners. The State typically obtains a Pipeline Right

of Way Access Agreement when placing material over private pipelines. In addition, when a

private entity submits a Right of Way Grant in order to place a pipeline within State

waterbottoms, the grant states that the grant is subservient to State/Federal projects. A copy of

the States Right of Way Grant is enclosed in Exhibit V. The LA State land managers have also

stated they have not had problems working with pipeline companies across the barrier islands,

and that pipeline owners have always welcomed additional cover for their lines because of the

added protection it provides.


21

The following chart presents oil and gas pipelines in or near the project areas.

REACH Pipeline ID Company Status Island Location

1 1498 United Gas Pipeline Company Active East Timbalier

1 2778 Duke Energy Hydrocarbons, LLC Active East Timbalier

1 3604 Cheveron Pipeline Co. Active East Timbalier

1 3043 Tennessee Gas Transmission Company Active East Timbalier

1 5796 \ 5797 California Oil Company Abandoned East Timbalier

1 2567 Equilon Pipeline Company, LLC Active Western Timbalier

1 9882 Louisiana Offshore Gathering S Active Eastern Timbalier

2 6138 Comstock Offshore, LLC Active East\Wine Islands

2 9145 Bayou City Pipelines, INC Active Whiskey\Trinity

2 3860 Williams Field Service Co. Active East Raccoon

2 7602 Trunkline Gas Company Active West Raccoon

There are several State Leases to Hilcorp Energy Company on Timbalier Island. As a project

feature, an access channel will be provided to two of these facilities, the SL 301 #101 well and

tank battery #19. The access channel will impact approximately 6 acres of state owned

waterbottoms. Based on communications with the Hilcorp Operations Manager for the

Terrebonne Bay Area, access is not required for any of its other facilities. The SL 16529 #2 well

was plugged and abandoned in early 2010. Although a well at SL 16529 #1 is still active and

producing, Hilcorp is amenable to plugging and abandoning it in the future mainly because this

well head is not accessible by land or water. Engineering did not identify this well as a relocation

item; however, during Preconstruction Engineering and Design phase, further investigations will

be conducted. Due to time constraints, a preliminary compensable interest report could not be

prepared to assess the projects impact on SL 16529 #1. Prior to project construction, a

Compensable Interest Report may need to be prepared in regards to the plugging and abandoning

of this well. Access will also be maintained to a Tennessee Connection facility on the western

end of the island. The access channel will impact approximately 2 acres of state owned

waterbottoms. Maps are located in Exhibit VI depicting the location of the facilities and wells

on Timbalier that are within the project footprint.

Numerous other oil and gas production areas are located in the project area, including oil and gas

wells and abandoned non-hazardous waste pits. These facilities/utilities are not anticipated to be

impacted by the project.

Navigation Servitude:

Derived from the Commerce Clause of the U.S. Constitution, article 1, section 8, clause 3, the

navigation servitude is the dominant right of the United States to use, control, and regulate

navigable waters and submerged lands. Because this is an ecosystem restoration project, it is

assumed at this time that the Navigation Servitude will not be asserted.


22

Acquisition Prior to Project Partnering Agreement (PPA):

The Non-Federal Sponsor prepared the Feasibility Study and is therefore aware of the risks

associated with the acquisition of private interests prior to congressional authorization of the

NER plan and the signing of the PPA.

Landowner Attitude:

The Non Federal Sponsor, the Louisiana Department of Wildlife and Fisheries, and private

owners appear to be in favor of the construction of the NER plan for this project.

This report has been prepared by the undersigned in accordance with Chapter 12 of the ER405-1-

12.

Significant contributions to the preparation of this report were provided by Ronnie Rabalais, SJB

Group, LLC, Division Manager Real Estate Services.

Prepared By:

Reviewed By:

______________________

Judith Y. Gutierrez

Chief, Appraisal & Planning

September 22, 2010

Erin A. Clark

USACE Appraiser

September 22, 2010


 

	

 

  
 
 




 

 
 




 

 

   


Quality Control Plan Checklist

Real Estate Plans

And other similar Feasibility-Level Real Estate Planning Documents

ER 405-1-12, Section 12-16, Real Estate Handbook, 1 May 1998

A Real Estate Plan (REP) is prepared in support of a decision document for full-Federal or cost

shared specifically authorized or continuing authority projects. It identifies and describes lands,

easements and rights-of-way (LER) required for the construction, operation, maintenance, repair,

replacement, and rehabilitation (OMRR&R) of a proposed project including requirements for

mitigation, relocations, borrow material, and dredged or excavated material disposal. It also

identifies and describes facility/utility relocations, LER value, and the acquisition process. The

REP does not just cover LER to be acquired by the non-Federal sponsor (NFS) or Government.

The report covers all LER needed for the project, including LER already owned by the NFS,

Federal Government, other public entities, or subject to the navigation servitude.

The REP must contain a detailed discussion of the following 20 topics, as set out in Section 12-

16 of the ER, including sufficient description of the rationale supporting each conclusion

presented. If a topic is not applicable to the project, this should be stated in the REP. The pages

of a REP should be numbered.

PROJECT: Terrebonne Basin Barrier Shoreline Restoration Project_

REPORT TITLE: Real Estate Plan ___________________________________

Date of Report: April 9, 2010__________ Date of REP: April 9, 2010, 2009

1. Purpose of the REP. __√___

a. Describe the purpose of the REP in relation to the project document that it supports.

b. Describe the project for the Real Estate reviewer.

c. Describe any previous REPs for the project.

2. Describe LER. __√____

a. Account for all lands, easements, and rights-of-way underlying and required for the

construction, OMRR&R of the project, including mitigation, relocations, borrow

material and dredged or excavated material disposal, whether or not it will need to be

acquired or will be credited to the NFS.

b. Provide description of total LER required for each project purpose and feature.

c. Include LER already owned by the Government, the NFS and within the navigation

servitude.

d. Show acreage, estates, number of tracts and ownerships, and estimated value.

e. Break down total acreage into fee and the various types and durations of easements.

f. Break down acreage by Government, NFS, other public entity, and private ownership,

and lands within the navigation servitude.


3. NFS-Owned LER.__√____

a. Describe NFS-owned acreage and interest and whether or not it is sufficient and

available for project requirements.

b. Discuss any crediting issues and describe NFS views on such issues.

4. Include any proposed Non-Standard Estates. __√___

a. Use Standard Estates where possible.

b. Non-standard estates must be approved by HQ to assure they meet DOJ standards for

use in condemnations.

c. Provide justification for use of the proposed non-standard estates.

d. Request approval of the non-standard estates as part of document approval.

e. If the document is to be approved at MSC level, the District must seek approval of the

non-standard estate by separate request to HQ. This should be stated in the REP.

f. Exception to HQ approval is District Chiefs of RE approval of non-standard estate if it

serves intended project purposed, substantially conforms with and does not materially

deviate from the standard estates found in the RE Handbook, and does not increase

cost or potential liability to the Government. A copy of this approval should be

included in the REP. (See Section 12-10c. of RE 405-1-12)

g. Although estates are discussed generally in topic 2, it is a good idea to also state in this

section which standard estates are to be acquired and attach a copy as an appendix.

The duration of any temporary estates should be stated.

5. Existing Federal Projects. __√___

a. Discuss whether there is any existing Federal project that lies fully of partially within

LER required for the project.

b. Describe the existing project, all previously-provided interests that are to be included

in the current project, and identify the sponsor.

c. Interest in land provided as an item of local cooperation for a previous Federal project

is not eligible for credit.

d. Additional interest in the same land is eligible for credit.

6. Federally-Owned Lands _√____

a. Discuss whether there is any Federally owned land included within the LER required

for the project.

b. Describe the acreage and interest owned by the Government.

c. Provide description of the views of the local agency representatives toward use of the

land for the project and issues raised by the requirement for this land.

7. Navigation Servitude. __√___

a. Identify LER required for the project that lies below the Ordinary High Water Mark, or

Mean High Water Mark, as the case may be, of a navigable watercourse.

b. Discuss whether navigation servitude is available

c. Will it be exercised for project purposes? Discuss why or why not.


d. Lands over which the navigation servitude is exercised are not to be acquired nor

eligible for credit for a Federal navigation or flood control project or other project to

which a navigation nexus can be shown.

e. See paragraph 12-7 of ER 405-1-12.

8. Map _√____

a. An aid to understanding

b. Clearly depicting project area and tracts required, including existing LER, LER to be

acquired, and lands within the navigation servitude.

c. Depicts significant utilities and facilities to be relocated, any known or potential

HTRW lands.

9. Induced Flooding can create a requirement for real estate acquisition. ___√___

a. Discuss whether there will be flooding induced by the construction and OMRR&R of

the project.

b. If reasonably anticipated, describe nature, extent and whether additional acquisition of

LER must or should occur.

c. Physical Takings Analysis (separate from the REP) must be done if significant induced

flooding anticipated considering depth, frequency, duration, and extent of induced

flooding.

. d. Summarize findings of Takings Analysis in REP. Does it rise to the level of a taking

for which just compensation is owed?

10. Baseline Cost Estimate as described in paragraph 12-18. __√___

a. Provides information for the project cost estimates.

b. Gross Appraisal includes the fair market value of all lands required for project

construction and OMRR&R.

c. PL 91-646 costs

d. Incidental acquisition costs

e. Incremental real estate costs discussed/supported.

f. Is Gross Appraisal current? Does Gross Appraisal need to be updated due to changes

in project LER requirements or time since report was prepared?

11. Relocation Assistance Benefits Anticipated. __√___

a. Number of persons, farms, and businesses to be displaced and estimated cost of

moving and reestablishment.

b. Availability of replacement housing for owners/tenants

c. Need for Last Resort Housing benefits

d. Real Estate closing costs

e. See current 49 CFR Part 24

12. Mineral Activity. __√___

a. Description of present or anticipated mineral activity in vicinity that may affect

construction, OMRR&R of project.

b. Recommendation, including rationale, regarding acquisition of mineral rights or

interest, including oil or gas.


c. Discuss other surface or subsurface interests/timber harvesting activity

d. Discuss effect of outstanding 3rd party mineral interests.

e. Does estate properly address mineral rights in relation to the project?

13. NFS Assessment _√____

a. Assessment of legal and professional capability and experience to acquire and provide

LER for construction, OMRR&R of the Project.

b. Condemnation authority

c. Quick-take capability

d. NFS advised of URA requirements

e. NFS advised of requirements for documenting expenses for credit.

f. If proposed that Government will acquire project LER on behalf of NFS, fully explain

the reasons for the Government performing work.

g. A copy of the signed and dated Assessment of Non-Federal Sponsor’s Real Estate

Acquisition Capability (Appendix 12-E) is attached to the REP.

14. Zoning in Lieu of Acquisition __√___

a. Discuss type and intended purpose

b. Determine whether the proposed zoning proposal would amount to a taking for which

compensation will be due.

15. Schedule __√___

a. Reasonable and detailed Schedule of land acquisition milestones, including LER

certification.

b. Dates mutually agreed upon by Real Estate, PM, and NFS. _____

16. Facility or Utility Relocations __√___

a. Describe the relocations, identity of owners, purpose of facilities/utilities, whether

owners have compensable real property interest.

b. A synopsis of the findings of the Preliminary Attorney’s Investigation and Report of

Compensable Interest is included in the REP as well as statements required by Sections

12-17c.(5) and (6).

c. Erroneous determinations can affect the accuracy of the project cost estimate and can

confuse Congressional authorization.

d. Eligibility for substitute facility

1. Project impact

2. Compensable interest

3. Public utility or facility

4. Duty to replace

5. Fair market value too difficult to determine or its application would result in an

injustice to the landowner or the public.

e. See Sections 12-8, 12-17, and 12-22 of ER 405-1-12.

17. HTRW and Other Environmental Considerations __√____

a. Discussion the impacts on the Real Estate acquisition process and LER value estimate

due to known or suspected presence of contaminants.



 !

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Sample

March 10, 2010

Mr. Robert Barham, Secretary

Department of Wildlife and Fisheries

Post Office Box 98000

Baton Rouge, La. 70898-9000

RE: Letter Agreement

Enhancement of Barrier Island Vegetation Demonstration Project TE-53

Isles Dernieres Barrier Islands Refuge

Terrebonne Parish, Louisiana

Dear Mr. Barham:

When executed by you, this letter shall constitute an agreement (the Agreement) by and

between the Office of Coastal Protection and Restoration (OCPR), as authorized and directed by

the policy of the Coastal Protection and Restoration Authority (CPRA), and the Louisiana

Department of Wildlife and Fisheries (DWF) whereby DWF authorizes OCPR to conduct

innovative methods of enhancing the successful establishment and cover of vegetation plantings for

the Enhancement of Barrier Island Vegetation Demonstration Project TE-53 (the Project) being

located on portions of the Isles Dernieres Barrier Islands Refuge (IDBIR) as identified on Exhibits

C and D attached hereto and made a part hereof.

DWF has no objection to OCPR, its agents or assigns, proceeding with the proposed Project

for integrated coastal protection purposes as defined in La. R. S. 49:214.2(4) as part of the Project

area shown on Exhibit A and pursuant to the Project Activity Summary on Exhibit B, both attached

hereto and made a part hereof, provided however, that OCPR complies with the following

stipulations:

1. This Agreement pertains to the IDBIR as shown on Exhibit A.

2. Prior to any activities on the IDBIR, OCPR shall contact Mr. Cassidy Lejeune, or his

assignee (Programs Manager), at (337) 373-0032, clejeune@wlf.la.gov to coordinate Project

details.


Sample

2

3. OCPR shall notify DWF of dates/times for the pre-bid and pre-construction meetings for

the Project so that DWF personnel can attend. OCPR must also provide DWF with

copies of any contracts issued for the implementation/construction of the Project.

4. OCPR shall abide by the IDBIR regulations as set forth in Exhibit E, attached hereto and

made a part hereof, unless otherwise agreed to by DWF.

5. All equipment and routes shall be approved by the Programs Manager.

6. No activities will be allowed within 1500 feet of nesting bird colonies unless approved by

the Programs Manager.

7. It shall be the responsibility of OCPR to repair any damages which may occur as a result of

the Project.

8. OCPR agrees to defend, indemnify and hold DWF harmless from and against any and all

claims, demands, expense and liability arising out of injury or death to any person or the

damage, loss or destruction of any property which may occur or in any way grow out of the

proposed Project.

9. This agreement allows OCPR to make minor modifications to the Project, but only insofar as

changes pertain to materials for project features and minor changes to project features

locations, as may be deemed necessary to fully and properly implement and maintain the

Project. Further, OCPR will notify DWF of such modifications and allow DWF to comment

on the modifications prior to the implementation of such modifications, and shall, when

practicable, consider and include any comments by DWF.

10. OCPR is responsible for all maintenance and repair of all project features. In the event

DWF notifies OCPR that project features require maintenance or repair, OCPR will provide

such maintenance or repair in a time frame that ensures that the objectives of the Project are

not compromised.

11. OCPR agrees that any use of mechanized equipment must be pre-approved by the DWF

Programs Manager referenced above.

12. OCPR will provide a fulltime, onsite construction inspector to ensure compliance with the

project plans, specs, and the terms and conditions of this Agreement. If, in the opinion of

DWF, OCPRs activities conflict with the plans, specs and/or the terms of this Agreement,

DWF shall contact OCPR fully describing what is in conflict. OCPR will immediately

contact the contractor to remedy said conflict. If the conflict is not remedied to DWFs

satisfaction within 2 days, DWF may suspend OCPRs activities until such time that conflict

can be appropriately addressed and remedied.


Sample

3

13. In the event any change or condition should develop that affects IDBIR and that would

affect OCPRs ability to perform the activities granted under this Agreement, DWF agrees to

notify OCPR at the following address:

Office of Coastal Protection and Restoration

P. O. Box 44027

Baton Rouge, LA 70804-4027

Phone: 225-342-7308

Fax: 225-342-9417

This Agreement shall become effective upon the signature of DWF and shall remain in

effect for three (3) years from the date hereof unless sooner terminated by the mutual consent of

OCPR and DWF.

OCPR may assign or transfer, in whole or in part, any or all of its rights hereunder, but only

to the extent necessary to implement the purposes of the Project on the said Lands.

This Agreement shall be binding upon, and inure to the benefit of, the parties hereto, their

successors in interest, transferees and assigns.

If the foregoing accurately reflects your understanding of the agreement between OCPR and

DWF relative to the referenced Project activities on the IDBIR, please evidence your approval by

signing the three (3) originals and returning the executed originals to this office. The documents

will be recorded in the public records of Terrebonne Parish, and a certified duplicate will be returned

to your office upon completion. Thank you for your cooperation in this matter.

Very truly yours,

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By:

Print Name '!,'-. -/+/

Title: Executive Director Print Name


Sample

4

ACCEPTED AND APPROVED THIS_______DAY OF_______ 2010.

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By:

Print Name *)$*' $*-,

Title: Secretary

Print Name


Sample

5

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Exhibit A Project Area

Exhibit B Project Summary

Exhibit C Whiskey Island Portion of Project

Exhibit D New Cut Dune Portion of Project

Exhibit E Regulations for Isles Dernieres Barrier Islands Refuge

c: Brad Miller, OCPR Project Manager

Jim Altman, OCPR Land Manager - Project File TE-53

F:\USERS\LAND\Projects\TE\TE53 Enhancement of Barrier Island Vegetation Demonstration Project TE-53\Agreements\DWF letter agreement.doc


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KNOW ALL MEN BY THESE PRESENTS: That pursuant to R.S. 41:1173, 36:1, 36:4, 39:8, 39:11(c) and 41:1 the State of Louisiana,

appearing herein by and through the Administrator of the State Land Office (hereinafter called Grantor), for and in consideration of the sum of

__________________________________________________________________ ($_____________________) DOLLARS and other valuable

considerations as may be provided elsewhere herein or in exhibit attached and made a part hereof does grant unto__________________________

__________________________________________________ (hereinafter called Grantee), the right, privilege and authority to construct, maintain,

operate, alter, repair, replace and remove a _________________________________________________________________ under, upon, over and

through the following described land, situated in the Parish of _______________________________, State of Louisiana, to wit:

The rights and privileges herein granted shall include the right to replace said project with one of similar or smaller class as set forth in

current Rules and Regulations of the Division of Administration and shall be exercised over a course up to but not in excess of __________ feet in

width during construction to revert to __________ feet after construction is herein granted. The route of the proposed project is shown on a plat(s)

identified as ____________________________________________________________ which is attached hereto and made a part hereof.

In the exercise of its rights under this grant, Grantee shall have the right, in the construction, operation and maintenance of the project to dig

trenches in or on said premises as Grantee may deem necessary or convenient, and to lay its project in the beds of such trenches.

TO HAVE AND TO HOLD the said right, privileges and authority, unto said Grantee, are granted without warranty and without recourse

even for the return of the aforementioned consideration for this grant, until such project is constructed and so long thereafter as the project is

maintained thereon.

It is understood and agreed that this right-of-way is for a term of twenty (20) years from _____________________________________ to

_______________________________________ with an option to renew for an additional twenty (20) year term. The option to renew shall be on

the same terms and conditions as the original agreement except that the consideration shall be adjusted to reflect the percentage of increase or

decrease in the cost of living index as established by the Consumer Price Index for Urban Wage Earners and Clerical Workers published by the

Bureau of Labor Statistics of the United States Department of Labor or any revision or equivalent to any such index published by the United States

Government, which has occurred from date of this instrument to the date of renewal provided however that in no event shall consideration of such

renewal be less than the consideration paid herein for the original term, and it is further understood and agreed that non-use thereof for a continuous

period of two (2) years shall operate as a forfeiture by the Grantee of this grant and consideration and that all rights hereunder shall be thereupon

terminated except when existing causes of force majeure actually prevent the use of the right-of-way and satisfactory evidence hereof is submitted

to the Grantor. In the event of such forfeiture, the Grantee shall have the right to remove the project, together with fittings, tie-overs, appliances and

equipment and any and all pertinent supplies and/or structures from the right-of-way within a period of one (1) year from the date of forfeiture,

provided that Grantee restores such area of the grant disturbed by the removal as near as practical to its natural state. There shall be no aboveground facilities except those designated and set out on the attached plat(s).

The Grantor reserves the right to fully use and enjoy the said premises subject to the rights herein granted.

If operations for construction are not commenced within two (2) years of the date of the execution of this agreement by the Grantor, then,

all rights of the Grantee thereunder shall terminate and the consideration shall be forfeited to Grantor.

All terms and expressed or implied covenants of this grant shall be subject to all Federal and State Laws.

Grantee agrees that due care shall be exercised in the construction operation of the project and its appurtenances and that Grantee shall be

fully and solely responsible for and shall defend, protect, indemnify and hold the State of Louisiana and all its agencies, boards and commissions

free and harmless from and against any and all claims for damages and all costs and expenses arising out of or incidental to Grantee's exercise of the

rights herein granted.

The granting of this right-of-way shall not be a bar or defense to the right of the State of Louisiana and its agencies, boards and

commissions to take any and all action necessary to seek abatement of construction or operations that unreasonably or unlawfully interfere with or

disturb the existing ecological regimen, including but not limited to the fishing, hunting, trapping and oyster industries, and to take action for any

and all damage to the existing ecological regimen which does not result from a reasonable exercise of the rights herein granted.

Any structure constructed on the right-of-way shall be of such design to allow passage of water craft common to the area.

Nothing herein contained shall be construed as to prohibit or preclude the Grantor herein from granting to other persons, associations or

corporations the right to cross over or under the right-of-way herein granted, provided that if such crossing should necessitate the alteration or

relocation of the project of the Grantee herein, all cost thereof shall be at the expense of such subsequent Grantee, subject to the following:

The parties hereto recognize that it might hereafter become necessary or desirable to widen, deepen or make some other work of public

improvement on land or in the streams or water bottoms within the right-of-way herein granted, and this grant is accepted under the express

condition and with the distinct understanding that, if any such work by the United States, the State of Louisiana, or any agency, board, commission,

department or political subdivision of either, makes it necessary to alter or relocate said project, the entire cost of such alteration or relocation shall

be borne by the Grantee, this responsibility on the part of the Grantee being part of the consideration for which this grant is made. This provision,

however, shall not prejudice the Grantee's right to receive indemnification and/or relocation costs, from the United States, the State of Louisiana or

SAMPLE


any agency, board, commission, department or political subdivision of either when there is an appropriation for payment of such costs.

It is agreed that Grantee shall not assign the rights granted hereunder without the written consent of Grantor and due payment of

assignment fees, but this prohibition shall not be applicable to any mortgage, deed of trust, pledge or other security contract which may be executed

by Grantee, and the consent of the Grantor to the execution of such agreements shall not be required.

Grantee agrees to construct and maintain the project, structures and its appurtenances in accordance with Parts 191, 192 and/or 195 of Title

49 of the Code of Federal Regulations, as amended, which sets forth minimum design, construction and maintenance standards for safety. Grantee

further agrees to comply with all other Federal and State Laws not in conflict which apply to design, construction, maintenance and operation.

It is further agreed that after the completion of the construction of the project, Grantee shall file in the office of the Grantor a plat showing

the actual location of the project on the above described lands.

The provisions of this agreement shall extend to and be binding upon the successors and assigns of Grantee, regardless of the appointment

of a receiver, adjudication in bankruptcy, reorganization, voluntary or otherwise, or the suspension, failure or insolvency of Grantee, or any successor

or assigns thereof.

Failure of Grantor to strictly or promptly enforce the rights and obligations herein shall not operate as a waiver thereof.

IN WITNESS WHEREOF, the STATE OF LOUISIANA has executed this right-of-way grant on this _______________ day of

___________________________, _________.

WITNESSES to the signature of the

Administrator of the State Land Office:

___________________________________

Printed Name:

_______________________________________________

ADMINISTRATOR, STATE LAND OFFICE

Printed Name:

___________________________________

Printed Name:________________________

ACKNOWLEDGMENT FOR THE ADMINISTRATOR OF THE STATE LAND OFFICE

STATE OF LOUISIANA

PARISH OF EAST BATON ROUGE

BEFORE ME, the undersigned authority, personally came and appeared __________, who by me being first duly sworn, deposed and said:

That she is one of the witnesses to the execution of the foregoing instrument and that she saw _____________ sign said instrument

as Administrator of the State Land Office for the State of Louisiana, in the presence of appearer and the other subscribing witness.

Sworn to and subscribed before me on this the

_______ day of ________________, ______. ___________________________________________________

Signature of Witness

Printed Name:

____________________________________

Notary Public

**********************************************************************************************************************

IN WITNESS WHEREOF, GRANTEE has executed this right-of-way on this __________ day of ____________________________,

__________.

WITNESSES:

_____________________________________

Printed Name:__________________________

___________________________________________________

TITLE:

Printed Name:_______________________________________

_____________________________________

SAMPLE


Printed Name:__________________________

ACKNOWLEDGMENT FOR CORPORATE GRANTEE

STATE OF ______________________

_______________ OF ___________________

BEFORE ME, the undersigned authority, personally came and appeared _________________________________________, who by me

being first duly sworn, deposed and said:

That he/she is one of the witnesses to the execution of the foregoing instrument and that he/she saw _______________________________

execute said instrument as ________________________of _____________________________________________ as the free act and deed of said

corporation in the presence of appearer and the other subscribing witness.

Sworn to and subscribed before me on this the

_______ day of ________________, _______. ___________________________________________________

Signature of Witness

Printed Name:_______________________________________

_____________________________________

Notary Public

SAMPLE


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Connection Point:

Tennessee Pipeline

Tank Battery #19

SL 301 #101

Terrebonne Basin Barrier Shoreline Restoration

Timbalier Island Plan E

Project Number: 11155

1,250 0 1,250 2,500 Feet

G:\ENGPROJ\LDD\11155_0 LCA Terrebonne Basin Barrier Shoreline\Spatial\MAPS\Island_Designs\Real_Estate\Wells\2010-0127-Timbalier-Min-Wells

Image Source:

U.S. Geological Survey

National Wetlands Research Center

2008 Aerial Photography

P.O. BOX 1751BATON ROUGE, LA. 70821

PHONE: (225) 769-3400

FAX: (225) 769-3596 September 2010

PH :FAX :3106 SOUTH HORSESHOE DRIVENAPLES, FLORIDA 34104

(239 ) 643-2324

(239 ) 643- 11 43

COASTALENGINEERINGCONSULTANTS INC.

Legend

Active Hilcorp WellConstruction Access ChannelOil and Gas Access CanalDuneBeachMarshTimbalier Plan E


6 acres

SL 1201 #14

SL 16529 #2 (P&A)

SL 16529 #1 (P&A)

SL 1201#15

SL 301 #101

Tank Battery #19

Breach

Terrebonne Basin Barrier Shoreline Restoration

Timbalier Island Plan E

Project Number: 11155

200 0 200 400 100 Feet

G:\ENGPROJ\LDD\11155_0 LCA Terrebonne Basin Barrier Shoreline\Spatial\MAPS\Island_Designs\Real_Estate\Wells\2010-0127-Timbalier-Min-Wells

Image Source:

U.S. Geological Survey

National Wetlands Research Center

2008 Aerial Photography

P.O. BOX 1751BATON ROUGE, LA. 70821

PHONE: (225) 769-3400

FAX: (225) 769-3596 September 2010

PH :FAX :3106 SOUTH HORSESHOE DRIVENAPLES, FLORIDA 34104

(239 ) 643-2324

(239 ) 643- 11 43

COASTALENGINEERINGCONSULTANTS INC.

Legend

Hilcorp WellsAccess CanalDuneBeachMarshTimbalier: Plan E


Connection Point:

Tennessee Pipeline

Terrebonne Basin Barrier Shoreline Restoration

Timbalier Island Plan E - Western Access Canal

Project Number: 11155

200 0 200 400 Feet

G:\ENGPROJ\LDD\11155_0 LCA Terrebonne Basin Barrier Shoreline\Spatial\MAPS\Island_Designs\Real_Estate\Wells\2010-0127-Timbalier-Min-Wells

Image Source:

U.S. Geological Survey

National Wetlands Research Center

2008 Aerial Photography

P.O. BOX 1751BATON ROUGE, LA. 70821

PHONE: (225) 769-3400

FAX: (225) 769-3596 September 2010

PH :FAX :3106 SOUTH HORSESHOE DRIVENAPLES, FLORIDA 34104

(239 ) 643-2324

(239 ) 643- 11 43

COASTALENGINEERINGCONSULTANTS INC.

Legend

Construction Access ChannelOil and Gas Access CanalDuneBeachMarshTimbalier Plan E


 !

* 
 +5 
 
 
 
 





 

  

* 
 +5 
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and/or

* 
 
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ER 405-1-12, paragraphs 12-9 and 12-10

PROJECT: LCA TERREBONNE BASIN BARRIER SHORELINE

RESTORATION PROJECT

Title and date of Decision Document which contains the REP requesting approval

of estate deviation or NSE approval____LCA Terrebonne Basin Barrier Shoreline

Restoration Feasibility Study___________________________________________

Subject line and date of memorandum requesting approval of estate deviation or NSE

approval ____N/A  Requested as an exhibit in the Real Estate Plan_________________

1. Does the proposed estate, whether standard or non-standard; provide sufficient interest

for the construction, operation, and maintenance of the project? ____YES___________

2. Coordination has been made with the following and they concur with use of the

proposed estate:

Project Management _____X_____ E&C __X_____

Operations _______X_________ Office of Counsel ____X_____

Coordination was made with the following other functional groups. __Environmental__

3. A statement of legal sufficiency from OC is attached to the REP or memo requesting

approval by HQ ____N/A______

4. Is the cost to acquire the proposed estate more than cost of acquiring a standard interest

with a standard estate? ___No____ Is this discussed in the request? ____YES______

5. Did the Non-Federal Sponsor (NFS) propose the deviation from appropriate interest or

use of a NSE? __No__

If so, why? _____________________________________________________________

If not, was the deviation or NSE coordinated with the NFS? ___Yes_____________


6. Can the non-standard estate be approved by the district Chief of RE? ____N/A_____

If so it must :

Serve the intended project purpose __________________

Substantially conform with and not materially deviate form the corresponding standard

estate __________

Does not increase the costs nor potential liability of the Government? _____________

7. Does the NSE conform to format of standard estates _____N/A?

8. Does the request for approval which goes through MVD to HQ, contain a detailed

explanation of and justification for the deviation as to interest to be acquired? _Yes_

9. Does the request contain a detailed explanation of each non-standard clause in the

estate? _N/A__ The request must detail the need for the language in relation to project

requirements. Each non-standard right to be acquired, restriction/prohibition placed on

fee owners interest and /or reservation to the fee owner must be fully discussed. Is the

acquisition or reservation of mineral rights held by the fee owner or outstanding 3rd party

mineral rights fully discussed in relation to the estate language and project requirements?

____N/A_____

If there are clauses found in the corresponding standard estate which have been deleted,

is there an explanation of the deletion? ____N/A____

10. Has the district deviated as to the appropriate interest on similar projects in the past?

___Yes___ If so, which project(s)? __The request to acquire easement rather than fee is

proposed for other LCA projects.

11. Has the proposed NSE been previously approved by HQ for use for a project in your

district? ____N/A____. If so, which project(s)? ____

Provide a copy of the previous approval.

A copy of this Checklist is attached to the REP or memorandum requesting a deviation as

to interest to be acquired or approval of a NSE. ___Yes___

___N/A________________________ Date: _____________________________

Realty Specialist or Appraiser

July 28, 2010

___________________________ Date: _____________________________

Branch or Section Chief



APPENDIX K

BENEFIT COST - INCREMENTAL

COST ANALYSIS



TERREBONNE BASIN BARRIER SHORELINE RESTORATION

FINAL FEASIBILITY REPORT

APPENDIX K - BENEFIT COST - INCREMENTAL COST ANALYSIS

TABLE OF CONTENTS

K1. INCREMENTAL COST ANALYSIS (IWR ANALYSIS)............................. 1-1

K1.1 DESCRIPTION .................................................................................................... 1-1

K1.2 RESTORATION PLANS........................................................................................ 1-1

K1.3 IWR SCREENING PROCESS................................................................................ 1-2

K1.4 IWR SCREENING RESULTS.............................................................................. 1-10

K2. INTERMEDIATE ARRAY OF ALTERNATIVES ....................................... 2-1

K3. COST EFFECTIVENESS AND INCREMENTAL COST ANALYSES ..... 3-1

K3.1 COST EFFECTIVENESS ....................................................................................... 3-1

K3.2 INCREMENTAL COST ANALYSIS ........................................................................ 3-2

K4. NATIONAL ECOSYSTEM RESTORATION PLAN ................................... 4-1

K4.1 SELECTION OF THE NATIONAL ECOSYSTEM RESTORATION PLAN..................... 4-1

K4.2 RENOURISHMENT CYCLES ................................................................................ 4-2

K4.2.1 Whiskey Island......................................................................................... 4-3

K4.2.2 Trinity Island............................................................................................ 4-6

K4.2.3 Raccoon Island with Terminal Groin....................................................... 4-8

K4.2.4 Timbalier Island ..................................................................................... 4-11

K4.3 DESCRIPTION OF NATIONAL ECOSYSTEM RESTORATION PLAN WITH

RENOURISHMENT............................................................................................ 4-13

K5 FIRST COMPONENT OF CONSTRUCTION .............................................. 5-1

K4.1 SELECTION OF THE FIRST COMPONENT OF CONSTRUCTION.............................. 5-1

K4.2 RENOURISHMENT CYCLES ................................................................................ 5-4

K4.3 DESCRIPTION OF FIRST COMPONENT OF CONSTRUCTION WITH

RENOURISHMENT.............................................................................................. 5-4

LIST OF FIGURES

K1-1. Results of IWR Iteration 1 ................................................................................ 1-12

K3-1. Results of IWR Iteration 2 Using the Intermediate Array of Alternatives ......... 3-1

K3-2. Incremental Cost and Output for the Best Buy Plans .......................................... 3-3

K4-1. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan C and Three Renourishment Alternatives on Whiskey

Island ................................................................................................................... 4-6

K4-2. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan C and Recommended Renourishment Scenario on Trinity

Island ................................................................................................................... 4-8

K4-3. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan E and Two Renourishment Alternatives on Raccoon

Island ................................................................................................................. 4-10

K4-4. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan E and Two Renourishment Alternatives on Timbalier

Island ................................................................................................................. 4-13

K5-1. Results of IWR Run Using the Extended Array ................................................. 5-4


LIST OF TABLES

K1-1. Summary of Habitat Acres for Raccoon Island Restoration Plans ...................... 1-3

K1-2. Summary of Habitat Acres for Raccoon Island Restoration Plans with

Breakwaters.......................................................................................................... 1-3

K1-3. Summary of Habitat Acres for Raccoon Island Restoration Plans with

Terminal Groin..................................................................................................... 1-4

K1-4. Summary of Habitat Acres for Whiskey Island Restoration Plans...................... 1-4

K1-5. Summary of Habitat Acres for Trinity Island Restoration Plans......................... 1-5

K1-6. Summary of Habitat Acres for East Island Restoration Plans ............................. 1-5

K1-7. Summary of Habitat Acres for Wine Island Restoration Plans ........................... 1-6

K1-8. Summary of Habitat Acres for Timbalier Island Restoration Plans .................... 1-6

K1-9. Summary of Habitat Acres for East Timbalier Island Restoration Plans ............ 1-7

K1-10. IWR Acres for Raccoon Island Restoration Plans............................................... 1-7

K1-11. IWR Acres for Raccoon Island Restoration Plans with Breakwaters.................. 1-8

K1-12. IWR Acres for Raccoon Island Restoration Plans with Terminal Groin............. 1-8

K1-13. IWR Acres for Whiskey Island Restoration Plans............................................... 1-8

K1-14. IWR Acres for Trinity Island Restoration Plans.................................................. 1-8

K1-15. IWR Acres for East Island Restoration Plans...................................................... 1-9

K1-16. IWR Acres for Wine Island Restoration Plans .................................................... 1-9

K1-17. IWR Acres for Timbalier Island Restoration Plans ............................................. 1-9

K1-18. IWR Acres for East Timbalier Island Restoration Plans ..................................... 1-9

K1-19. IWR Input .......................................................................................................... 1-10

K2-1. Summary of Intermediate Array of Restoration Plans......................................... 2-3

K3-1. Cost Effective Alternatives.................................................................................. 3-2

K3-2. Incremental Cost Analysis ................................................................................... 3-3

K4-1. NER Plan Beach and Dune Fill Design Parameters ............................................ 4-2

K4-2. NER Plan Marsh Fill Design Parameters............................................................. 4-2

K4-3. NER Plan Preliminary Assessment of Borrow Areas and Cut Volumes............. 4-2

K4-4. Whiskey Island Plan C: Island Acres and Beach Dimensions Summary ............ 4-3

K4-5. Whiskey Island RA1: Island Acres and Beach Dimensions Summary ............... 4-4

K4-6. Whiskey Island RA2: Island Acres and Beach Dimensions Summary ............... 4-5

K4-7. Whiskey Island RA3: Island Acres and Beach Dimensions Summary ............... 4-5

K4-8. Trinity Island Plan C: Island Acres and Beach Dimensions Summary ............... 4-6

K4-9. Trinity Island Acres and Beach Dimensions Summary....................................... 4-7

K4-10. Raccoon Island Plan E with Terminal Groin: Island Acres and Beach

Dimensions Summary ......................................................................................... 4-8

K4-11. Raccoon Island RA1: Island Acres and Beach Dimensions Summary................ 4-9

K4-12. Raccoon Island RA2: Island Acres and Beach Dimensions Summary.............. 4-10

K4-13. Timbalier Island Plan E: Island Acres and Beach Dimensions Summary......... 4-11

K4-14. Timbalier Island RA1: Island Acres and Beach Dimensions Summary............ 4-12

K4-15. Timbalier Island RA2: Island Acres and Beach Dimensions Summary............ 4-12

K4-16. NER Plan Beach / Dune Fill and Marsh Fill Design Parameters ...................... 4-14

K4-17. NER Plan Borrow Areas and Cut Volumes....................................................... 4-14

K5-1. Summary of Extended Array of Restoration Plans.............................................. 5-2

K5-2. First Component of Construction Beach/Dune Fill and Marsh Fill Design

Parameters............................................................................................................ 5-5

K5-3. First Component of Construction Borrow Areas and Cut Volumes.................... 5-5


1-1

K1. INCREMENTAL COST ANALYSIS (IWR ANALYSIS)

K1.1 DESCRIPTION

The United States Army Corps of Engineers (USACE) Institute for Water Resources

(IWR) developed the IWR Planning Suite which assists with formulation and comparison

of alternative plans. The IWR Planning Suite assists with plan formulation by combining

solutions to planning problems and calculating the additive effects of each combination.

It also assists with plan comparison by conducting a Cost Effectiveness / Incremental

Cost Analysis (CE/ICA), identifying the plans which are the best financial investments -

Best Buy Plans, and displaying the effects of each on a range of decision variables. The

IWR Planning Suite 1.0.11.0 was used in the IWR screening process of the Louisiana

Coastal Area (LCA) Terrebonne Basin Barrier Shoreline Restoration (TBBSR) Study

solutions.

K1.2 RESTORATION PLANS

Five (5) restoration design plans, denoted by Plans A through E, were developed in

Appendix L for the seven (7) Terrebonne Basin barrier islands: Raccoon, Whiskey,

Trinity, East, Wine, Timbalier, and East Timbalier Islands.

Plan A is the No Action Plan, that is, no sediment is imported to restore the islands

components (i.e., beach, dune, and marsh). The restoration design for Plan B provides for

the minimal geomorphologic form and ecologic function on each island defined through

analysis of historic planforms and elevations and storm erosion modeling such that the

restored island retains this form and function after being subjected to the design storms.

Plans C through E are scalars of Plan B that investigated incremental increases in the

scales of beach, dune and marsh planforms and elevations to provide plan formulators the

ability to determine the optimal increment for restoration of the geomorphologic form

and ecologic function of these islands. The optimal level of restoration is defined as the

best balance of environmental benefits (e.g., habitat acres), constructability as constrained

by available sediment volumes in identified borrow sources, and cost effectiveness. Plan

C provides for the minimal geomorphologic form and ecologic function on each island

along with 5 years of advanced fill. Plan D provides for the minimal geomorphologic

form and ecologic function on each island along with 10 years of advanced fill. Plan E

provides for the minimal geomorphologic form and ecologic function on each island

along with 25 years of advanced fill.

An additional option was derived for Wine Island that included placing beach compatible

sand within the existing rock revetment locally known as the Wine Island Ring. Two

additional options were derived for Raccoon Island including the construction of eight

additional breakwaters (BW) or construction of a terminal groin (TG) (Appendix L).


1-2

     

 

( 1 5) ( 5 10) ( 10 20) # of years # #

betweenTY/49 betweenTY/49 betweenTY/49 22 2

( 20 30) ( #

betweenTY/49 2

WeightedAverageCalculation TY TY TY TY TY TY of years of years

TY TY T of years

 

 



 

     	
 	 
 	 
     

  	 
        

       

30 40) ( 40 50) (235 253) 4 # #

betweenTY/49 betweenTY/49 2 2 2 49

(253 266) 5 (266 255) 10 (255 260) 10 (260 248) 10 (248 23)

2 49 2 49 2 49 2 49 2

Y TY TY TY   of years of years  





     	 
 	 
 	
     

      	 
	 
	 
	 
	        10

49

231Acres 


K1.3 IWR SCREENING PROCESS

Restoration design plans and measures were developed and analyzed through the plan

formulation process (Integrated Feasibility Study and Final Environmental Impact Statement

Report, Section 3). Because of the millions of potential alternatives comprised of island

measure(s) and borrow area combinations (Appendix L), an IWR screening process was

conducted to identify the most cost effective alternatives for consideration in developing

the Intermediate Array of Alternatives. The input parameters for the IWR screening run

included habitat acres and conceptual cost estimates (Appendix L) specific to the island

measures carried through the plan formulation process.

The habitat acres were calculated based on the Wetland Value Assessment (WVA)

methodology which states that the key habitat components, dune, supratidal (beach), and

intertidal (marsh), combine to provide the optimum metric by which the islands should be

compared (Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA),

2002). The methodology projects dune (5 feet (ft) North American Vertical Datum of

1988 (NAVD 88)), supratidal (2 ft NAVD 88 and  4.9 ft NAVD 88), and intertidal (

0.0 ft NAVD 88 and  1.9 ft NAVD 88) acres at specific Target Years (TYs). The PDT

chose the following TYs: TY0, TY1, TY5, TY10, TY20, TY30, TY40, and TY50 along

with the year of disappearance for each habitat component. Because the habitat acres

constantly change due to erosion, sea level change, subsidence, overwash, and barrier

island migration, weighted averages were calculated over the 50-year period of analysis

for a balanced comparison of measures. An example weighted average calculation is

presented below (Raccoon Island, Plan B, intertidal habitat):

TY1 TY5 TY10 TY20 TY30 TY40 TY50

235 253 266 255 260 248 23

Tables K1-1 through K1-9 present habitat acres at specific TYs and weighted average

acres calculated for individual islands and design plans.


1-3

Table K1-1. Summary of Habitat Acres for Raccoon Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 000 0 0 0 0 0 0

A Supratidal 51 51 30 10 3 0 0 0 7

Intertidal 188 184 161 137 76 55 0 0 70

Dune 0 45 33 15 1 0 0 0 7

B Supratidal 51 226 194 162 150 83 25 0 105

Intertidal 188 235 253 266 255 260 248 23 231

Dune 0 50 38 22 8 0 0 0 11

C Supratidal 51 291 215 192 174 110 62 4 132

Intertidal 188 237 300 301 295 306 277 223 285

Dune 0 60 45 25 14 0 0 0 13

D Supratidal 51 460 445 231 210 120 67 29 179

Intertidal 188 122 146 339 335 341 307 263 298

Dune 0 63 50 29 20 0 0 0 16

E Supratidal 51 688 675 657 630 144 72 51 368

Intertidal 188 39 39 40 39 478 457 425 253

Table K1-2. Summary of Habitat Acres for Raccoon Island Restoration Plans

with Breakwaters

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 0 00 0 0 0 0 0 0

A Supratidal 51 51 30 10 3 0 0 0 7

Intertidal 188 184 161 137 76 55 0 0 70

Dune 0 45 33 15 6 0 0 0 8

B Supratidal 51 226 198 163 173 112 62 0 123

Intertidal 188 237 254 267 254 264 259 38 236

Dune 0 50 38 22 8 0 0 0 11

C Supratidal 51 292 219 193 200 142 92 14 152

Intertidal 188 239 302 303 297 307 300 262 295

Dune 0 60 45 25 14 0 0 0 13

D Supratidal 51 461 449 232 220 158 96 34 196

Intertidal 188 122 148 340 352 336 339 307 312

Dune 0 63 50 28 20 0 0 0 15

E Supratidal 51 689 679 658 656 188 109 68 393

Intertidal 188 39 40 40 40 467 489 472 263


1-4

Table K1-3. Summary of Habitat Acres for Raccoon Island Restoration Plans

with Terminal Groin

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 0 00 0 0 0 0 0 0

A Supratidal 51 51 30 10 3 0 0 0 7

Intertidal 188 184 161 137 76 55 0 0 70

Dune 0 45 33 15 3 0 0 0 8

B Supratidal 51 226 198 165 170 107 36 0 117

Intertidal 188 237 254 267 254 264 279 34 240

Dune 0 50 38 22 8 0 0 0 11

C Supratidal 51 291 218 194 194 137 86 12 148

Intertidal 188 238 302 302 296 307 300 258 294

Dune 0 60 45 25 14 0 0 0 13

D Supratidal 51 460 448 232 218 156 93 34 194

Intertidal 188 122 147 341 348 332 329 303 308

Dune 0 63 50 29 20 0 0 0 16

E Supratidal 51 688 678 659 650 182 106 66 389

Intertidal 188 38 39 40 39 466 486 468 261

Table K1-4. Summary of Habitat Acres for Whiskey Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 0 0 0 0 0 0 0 0 0

A Supratidal 377 367 40 4 0 0 0 0 19

Intertidal 443 436 692 616 468 375 0 0 271

Dune 0 57 53 0 0 0 0 0 7

B Supratidal 377 614 220 164 0 0 0 0 70

Intertidal 443 509 830 801 786 594 410 276 613

Dune 0 65 61 57 0 0 0 0 17

C Supratidal 377 830 328 223 84 0 0 0 115

Intertidal 443 377 808 828 847 717 472 363 669

Dune 0 69 65 61 0 0 0 0 18

D Supratidal 377 917 533 288 167 1 0 0 165

Intertidal 443 376 690 850 854 785 521 355 686

Dune 0 80 76 71 0 0 0 0 21

E Supratidal 377 1323 1127 1039 938 259 75 0 576

Intertidal 443 250 376 379 375 875 782 475 566


1-5

Table K1-5. Summary of Habitat Acres for Trinity Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 39 32 4 3 0 0 0 0 2

A Supratidal 232 206 137 52 3 1 0 0 30

Intertidal 311 326 327 245 72 19 0 0 99

Dune 39 126 92 23 0 0 0 0 17

B Supratidal 232 338 237 208 43 0 0 0 76

Intertidal 311 569 626 629 627 460 279 33 459

Dune 39 129 122 67 0 0 0 0 27

C Supratidal 232 456 316 270 190 4 0 0 129

Intertidal 311 564 632 635 594 561 380 199 512

Dune 39 126 116 102 0 0 0 0 31

D Supratidal 232 1072 1004 351 324 124 0 0 281

Intertidal 311 72 73 642 578 577 501 298 476

Dune 39 123 115 107 0 0 0 0 32

E Supratidal 232 1399 1329 1237 1157 422 217 32 738

Intertidal 311 67 66 67 69 608 618 593 344

Table K1-6. Summary of Habitat Acres for East Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 35 23 5 4 0 0 0 0 2

A Supratidal 178 176 86 46 6 0 0 0 23

Intertidal 71 59 110 101 58 16 0 0 43

Dune 35 88 59 18 0 0 0 0 12

B Supratidal 178 229 165 140 33 0 0 0 53

Intertidal 71 362 404 405 401 290 171 46 294

Dune 35 89 81 50 0 0 0 0 19

C Supratidal 178 296 213 175 122 2 0 0 84

Intertidal 71 372 410 412 388 360 242 122 330

Dune 35 84 74 67 0 0 0 0 20

D Supratidal 178 718 674 231 208 73 0 0 184

Intertidal 71 33 34 418 377 382 314 192 307

Dune 35 77 75 69 0 0 0 0 20

E Supratidal 178 950 898 837 770 273 139 17 492

Intertidal 71 33 33 34 39 402 402 379 220


1-6

Table K1-7. Summary of Habitat Acres for Wine Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 1 0 0 0 0 0 0 0 0

A Supratidal 5 5 2 20000 1

Intertidal 6 7 6 5 3 1 0 0 3

Dune 1 12 11 10 0 0 0 0 3

B Supratidal 5 97 75 61 47 13 0 0 32

Intertidal 6 97 109 109 106 111 96 5 95

Dune 1 13 12 11 0 0 0 0 3

C Supratidal 5 109 90 76 64 29 2 0 44

Intertidal 6 117 125 126 122 129 128 9 114

Dune 1 12 11 10 9 0 0 0 5

D Supratidal 5 118 98 85 62 38 10 0 49

Intertidal 6 140 149 150 146 150 151 7 134

Dune 1 11 10 9 8 0 0 0 4

E Supratidal 5 338 328 314 288 76 47 0 176

Intertidal 6 17 17 17 17 210 210 229 117

Dune 1 15 12 4 0 0 0 0 2

Supratidal 5 11 8 63100 3

Ring

Intertidal 6 3 4 4 3 3 2 1 3

Table K1-8. Summary of Habitat Acres for Timbalier Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 57 53 31 8 0 0 0 0 6

A Supratidal 549 529 266 286 93 18 1 0 113

Intertidal 374 373 541 392 289 149 37 2 222

Dune 57 155 130 13 0 0 0 0 20

B Supratidal 549 748 566 524 236 38 1 0 219

Intertidal 374 726 811 822 829 695 450 175 651

Dune 57 193 160 130 0 0 0 0 42

C Supratidal 549 1550 630 496 438 134 3 0 314

Intertidal 374 85 916 933 826 833 644 373 738

Dune 57 191 161 136 0 0 0 0 43

D Supratidal 549 1761 1668 600 499 187 4 0 457

Intertidal 374 83 88 1041 978 994 843 571 804

Dune 57 215 183 160 0 0 0 0 50

E Supratidal 549 2346 2257 2130 1996 629 330 53 1238

Intertidal 374 69 71 74 76 1148 1123 1088 611


1-7

Table K1-9. Summary of Habitat Acres for East Timbalier Island Restoration Plans

Target Year (TY)

Plan

Habitat

Type TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50 Weighted

Average

Dune 7 1 1 0 0 0 0 0 0

A Supratidal 129 74 60 46 9 2 1 0 18

Intertidal 173 133 140 111 98 49 17 4 69

Dune 7 63 58 54 0 0 0 0 16

B Supratidal 129 314 240 199 175 70 7 0 117

Intertidal 173 452 476 474 456 459 405 7 405

Dune 7 86 67 62 0 0 0 0 19

C Supratidal 129 972 327 238 158 52 7 0 150

Intertidal 173 71 702 714 664 587 552 496 595

Dune 7 93 71 66 0 0 0 0 20

D Supratidal 129 1077 1062 351 359 256 157 56 358

Intertidal 173 60 72 734 673 682 676 670 604

Dune 7 120 83 78 0 0 0 0 24

E Supratidal 129 1641 1617 1587 1556 444 192 244 931

Intertidal 173 99 91 86 71 1086 1227 1066 621

The weighted average habitat acres were used to compute IWR acres, i.e., acres used as

input into the IWR program. Based upon the WVA methodology (CWPPRA, 2002), the

intertidal habitat acres were adjusted by a weighting factor of 17/14 and combined with

dune and supratidal acres to yield total adjusted habitat acres. Because the No Action

Plan (Plan A) is always required to have zero acres in the IWR program, Plan As total

adjusted habitat acres were subtracted from Plan B through Plan Es acres to produce the

final net IWR acres as presented in Tables K1-10 through K1-18.

Table K1-10. IWR Acres for Raccoon Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 7 70 85 92 0

B 112 231 281 393 301

C 143 285 347 489 397

D 192 298 362 554 462

E 384 253 308 692 599

*adjusted to account for WVA weighting factor of 17/14


1-8

Table K1-11. IWR Acres for Raccoon Island Restoration Plans with Breakwaters

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 7 70 85 92 0

B 131 236 287 418 326

C 162 295 358 520 428

D 209 312 378 587 495

E 408 263 319 727 635

*adjusted to account for WVA weighting factor of 17/14

Table K1-12. IWR Acres for Raccoon Island Restoration Plans with Terminal Groin

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 7 70 85 92 0

B 124 240 291 416 324

C 159 294 357 516 424

D 207 308 374 581 489

E 405 261 317 722 630

*adjusted to account for WVA weighting factor of 17/14

Table K1-13. IWR Acres for Whiskey Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 19 271 329 348 0

B 77 613 744 822 474

C 132 669 812 944 596

D 183 686 833 1015 667

E 597 566 687 1284 936

*adjusted to account for WVA weighting factor of 17/14

Table K1-14. IWR Acres for Trinity Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 32 99 121 153 0

B 93 459 558 651 498

C 155 512 622 777 625

D 313 476 578 891 738

E 770 344 417 1187 1035

*adjusted to account for WVA weighting factor of 17/14


1-9

Table K1-15. IWR Acres for East Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 25 43 52 78 0

B 64 294 357 422 344

C 102 330 401 503 426

D 205 307 373 577 500

E 513 220 267 780 703

*adjusted to account for WVA weighting factor of 17/14

Table K1-16. IWR Acres for Wine Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A1 34 4 0

B 35 95 116 151 147

C 47 114 138 185 181

D 54 134 163 217 213

E 180 117 142 323 319

Ring 5 3 3 9 5

*adjusted to account for WVA weighting factor of 17/14

Table K1-17. IWR Acres for Timbalier Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 119 222 269 388 0

B 239 651 790 1029 641

C 357 738 897 1253 865

D 501 804 976 1477 1088

E 1288 611 741 2029 1641

*adjusted to account for WVA weighting factor of 17/14

Table K1-18. IWR Acres for East Timbalier Island Restoration Plans

Habitat Acres

Plan Dune & Supratidal

Subtotal Intertidal IntertidalAdjusted*

Grand Total

Adjusted

IWR Program

Input

A 18 69 84 102 0

B 133 405 492 624 523

C 169 595 723 892 791

D 379 604 734 1112 1011

E 955 621 754 1709 1607

*adjusted to account for WVA weighting factor of 17/14


1-10

The WVA model is presently undergoing model certification in accordance with USACE

EC 1105-2-407, May 2005 Planning Models Improvement Program: Model Certification.

The model has undergone external review which is documented in the July 8, 2009, Draft

Model Certification Review Report for the WVA Models prepared by the Battelle

Memorial Institute for the USACE, Ecosystem Planning Center of Expertise. The WVA

revision documentation and spreadsheets have been submitted to the Ecosystem Center of

Expertise (ECO-PCX). The ECO-PCX has reviewed the revisions and will forward a

recommendation to certify the model for use in the LCA projects.

Since the WVA was still in the process of being certified, the projects using the WVA

model were required to respond to specific comments related to the ongoing certification

process and the use of WVA on the specific project. The specific comments and

responses for the WVA as it relates to the LCA TBBSR Study can be found in Annex K1. Based on satisfactory responses to these comments, ECO-PCX has cleared the WVA

model for use in evaluating the alternatives considered in the LCA TBBSR Study.

K1.4 IWR SCREENING RESULTS

Table K1-19 summarizes the IWR input used in the IWR screening run.

Table K1-19. IWR Input

Island

(# of Scales)

Scale

# Description Cost,($1,000)

Net

Acres

0 Plan A 0 0

1 Plan B 54,400 301

2 Plan C 58,300 397

3 Plan D 64,100 462

4 Plan E 81,100 599

5 Plan B with BW 58,100 326

6 Plan C with BW 62,000 428

7 Plan D with BW 67,800 495

8 Plan E with BW 84,800 635

9 Plan B with TG 56,600 324

10 Plan C with TG 60,600 424

11 Plan D with TG 66,400 489

Raccoon

(13)

12 Plan E with TG 83,400 630

0 Plan A 0 0

1 Plan B 63,500 474

2 Plan C 73,900 596

3 Plan D 84,500 667

Whiskey

(5)

4 Plan E 124,000 936

0 Plan A 0 0

1 Plan B 67,100 498

2 Plan C 77,600 625

Trinity

(5)

3 Plan D 93,400 738


1-11

Island

(# of Scales)

Scale

# Description Cost,($1,000)

Net

Acres

4 Plan E 136,700 1035

0 Plan A 0 0

1 Plan B 56,500 344

2 Plan C 62,400 426

3 Plan D 72,600 500

East

(5)

4 Plan E 102,300 703

0 Plan A 0 0

1 Plan B 42,500 147

2 Plan C 43,900 181

3 Plan D 45,800 213

4 Plan E 51,500 318

Wine

(6)

5 Ring* 16,400 5

0 Plan A 0 0

1 Plan B 83,400 641

2 Plan C 97,400 865

3 Plan D 113,000 1088

Timbalier

(5)

4 Plan E 168,000 1641

0 Plan A 0 0

1 Plan B 144,000 523

2 Plan C 180,000 791

3 Plan D 229,000 1011

East

Timbalier

(5)

4 Plan E 375,000 1607

BW denotes breakwaters

TG denotes Terminal Groin

* this plan includes filling the existing rock ring of Wine Island

A total of 243,750 plans were generated in IWR. It produced 360 cost effective plan

alternatives ranging in conceptual cost between $0 (No Action) to $1.04 billion (Raccoon

with BW, Whiskey, Trinity, East, Wine, Timbalier, and East Timbalier  all Plan E).

Fourteen (14) of the cost effective plans were Best Buy Plans. Figure K1-1 presents an

IWR graph which depicts all of the plans including non cost effective, cost effective and

Best Buys.


1-12

Figure K1-1. Results of IWR Iteration 1

Of the 243,750 Generated Plans, 360 were Cost-Effective (blue triangles) and 14 were Best Buys

(red squares).

BB1

BB2

BB3

BB4

BB5 BB6

BB7

BB8

BB9

BB10

BB11

BB12

BB13, 14


2-1

K2. INTERMEDIATE ARRAY OF ALTERNATIVES

Based on the results of the IWR analysis presented in Section K1, five (5) Best Buy Plans

were recommended for inclusion in the Intermediate Array of Alternatives presented in

Table K2-1. It should be noted that because the conceptual cost estimates in the IWR

screening were developed separately for individual islands and dune/beach and marsh fill

components, they did not account for potential reductions due to shared mobilization/

demobilization as well as other fixed costs (Appendix L). The conceptual cost estimates

were subsequently refined through the reduction in redundancies for analyzing and

developing alternatives to carry forward into the Intermediate Array (Appendix L).

Preliminary cost estimates were developed from the refined conceptual costs with the

inclusion of preconstruction, engineering, and design, real estate, sand fencing, and

vegetative plantings. For the preliminary cost estimates, the costs associated with

supervision and inspection from the refined conceptual costs were revised and recategorized for monitoring and operations and maintenance (O&M) (Appendix L).

According to Section E-36c of ER 1105-2-100, all costs should be calculated in terms of

present worth using the appropriate discount rate and annualized. Therefore, the

preliminary costs were annualized at a discount rate of 4.375%, with a base year of 2012.

It should be noted that for Best Buy Plans 4 and 5, the volume of required marsh fill

exceeds the volume of marsh sediments identified in the cleared marsh borrow areas,

thus, sand borrow areas were selected to provide the additional sediment to complete the

marsh fill templates. Furthermore, the WVA methodology was applied to compute

Average Annual Habitat Units (AAHUs). The Habitat Units, which represent a numerical

combination of quality and quantity existing at any given point in time resulting from the

future without and future with project scenarios, were annualized and averaged over the

50-year period of analysis to determine AAHUs. The difference in AAHUs between two

scenarios represents the net benefits attributable to the LCA TBBSR Study in terms of

habitat quality and quantity. The No Action Plan A AAHUs were subtracted from Plan B

through Plan Es AAHUs to yield the net AAHUs that represent Plan B through Plan Es

net benefits compared to the No Action Plan scenario. Plan As net AAHUs are thus zero.

To apply a system-wide approach of restoring as many islands within the Study Area and

to ensure that other alternatives that could provide effective solutions and can be

constructed with cleared sediment sources, additional solutions were further analyzed. All

possible minimized (Plan B) three- and four-island combinations that could be

constructed with cleared sediment sources were developed. The most cost effective

combinations whose refined conceptual cost estimate did not exceed the Best Buy Plans

included in the Intermediate Array of Alternatives, of which there were four (4), were

included in the Intermediate Array of Alternatives.

Finally, a system-wide barrier island restoration measure which would restore all seven

(7) islands to their minimized design (Plan B) completed the Intermediate Array of

Alternatives.


2-2

In summary, the ten (10) Intermediate Array alternatives were grouped into four (4)

categories.

1) No Action  The No-Action Alternative assumes there would be no future barrier

island restoration within the Study Area. The barrier islands will continue to be subjected

to the factors and processes that are contributing to the loss of the Timbalier Islands and

the Isles Dernieres and will result in a direct loss of the barrier islands to open water.

2) Best Buy  The Best Buy alternative based on the IWR screening provides the

greatest increase in the value of the output variable for the least increase in the value of

the cost variable. In other words, the Best Buy alternative yields the maximum habitat

acres at the lowest cost per unit. If the budget falls between two Best Buy alternatives,

the lower cost plan could be scaled-up. The Best Buy alternative is geared less toward

the system-wide approach of restoring all of the islands and more toward restoring the

island or islands that are most cost effective.

3) Maximum number of islands constructible with cleared sediment sources - This

alternative would favor those islands where the total costs are lowest, allowing for more

islands to be created using cleared sediment sources noting they may or may not be cost

effective based on the IWR screening. The rationale for advancing these alternatives is

based on a system wide approach of restoring as many of the islands within the Study

Area as possible. The signals received from the public meetings, both scoping and

Coastal Protection and Restoration Authority stakeholder, indicate a general desire to

restore all of the islands in the Study Area. Concentrating restoration efforts on only one

or two cost effective islands may well meet with public opposition, focusing on the

equitability of the alternatives evaluation process.

4) System-wide barrier island restoration  This alternative would take a full system-wide

approach to restoring the barrier islands. Each of the seven barrier islands would be

restored to their minimal geomorphologic form and ecologic function. Similar to the

alternatives that include the most islands that can be constructed with cleared sediment

sources, this alternative may or may not be cost effective based on the IWR screening.

The rationale is the same, that being; the significant stakeholder input received during

plan formulation indicates a general desire to restore all of the islands in the Terrebonne

Basin. It is noted that for this alternative, the volume of required marsh fill exceeds the

volume of marsh sediments identified in the cleared marsh borrow areas, thus, sand

borrow areas were selected to provide the additional sediment to complete the marsh fill

templates.

The descriptions of the ten (10) alternatives along with their respective preliminary

annualized costs and net AAHUs are summarized in Table K2-1. The cost data are

presented in Appendix L. The AAHU data are presented in the Integrated Feasibility Study

and Final Environmental Impact Statement Report, Section 3.


Table K2-1. Summary of Intermediate Array of Restoration Plans

Alternative Category Net AAHU Preliminary Cost* ($) Annualized Cost** ($)

Annualized

Cost per

AAHU

($/ AAHU)

Description

1 No Action (Plan A) No Action 0 0 0 0 This alternative does not include any restoration.2 Timbalier (Plan E) Best Buy 871 170,000,000 8,710,000 10,000

Restoration of Timbalier Island to its minimalgeomorphologic form and ecologic function along with 25years of advanced fill.

3 Whiskey (Plan C) / Timbalier (Plan E) Best Buy 1,250 247,000,000 12,640,000 10,120

Restoration of Whiskey Island to its minimal geomorphologicform and ecologic function along with 5 years of advanced fillcombined with restoration of Timbalier Island to its minimalgeomorphologic form and ecologic function along with 25years of advanced fill.

4

Whiskey (Plan C) /Trinity (Plan C) /Timbalier (Plan E)

Best Buy 1,637 329,000,000 16,820,000 10,280

Restoration of Whiskey and Trinity Islands to their minimalgeomorphologic form and ecologic function along with 5years of advanced fill combined with restoration of TimbalierIsland to its minimal geomorphologic form and ecologicfunction along with 25 years of advanced fill.

5

Raccoon with TG(Plan E) /Whiskey (Plan C) /Trinity (Plan C) /Timbalier (Plan E)

Best Buy 2,063 408,000,000 20,830,000 10,100

Restoration of Whiskey and Trinity Islands to their minimalgeomorphologic form and ecologic function along with 5years of advanced fill combined with restoration of Raccoonand Timbalier Islands to their minimal geomorphologic formand ecologic function along with 25 years of advanced fill andconstruction of a terminal groin on the western end ofRaccoon Island.

6

Raccoon (Plan B) /Whiskey (Plan B) /Trinity (Plan B)

Max # of Islands

Constructible

with Cleared

Sediment Sources

785 177,000,000 9,040,000 11,510 Restoration of Raccoon, Whiskey, and Trinity Islands, all to their minimal geomorphologic form and ecologic function.

7

Raccoon with BW(Plan B) /Whiskey (Plan B) /Trinity (Plan B)

Max # of Islands

Constructible

with Cleared

Sediment

Sources

808 182,000,000 9,280,000 11,490

Restoration of Raccoon, Whiskey, and Trinity Islands, all totheir minimal geomorphologic form and ecologic function,along with construction of eight additional breakwaters on thewestern end of Raccoon Island.

8

Raccoon with TG (Plan B)/ Whiskey (Plan B) /Trinity (Plan B)

Max # of Islands

Constructible

with Cleared

Sediment

801 180,000,000 9,190,000 11,470

Restoration of Raccoon, Whiskey, and Trinity Islands, all totheir minimal geomorphologic form and ecologic function,along with construction of a terminal groin on the western endof Raccoon Island.


Alternative Category Net AAHU Preliminary Cost* ($) Annualized Cost** ($)

Annualized

Cost per

AAHU

($/ AAHU)

Description

Sources

9

Raccoon (Plan B) /Whiskey (Plan B) /Timbalier (Plan B)

Max # of Islands

Constructible

with Cleared

Sediment

Sources

890 199,000,000 10,160,000 11,420 Restoration of Raccoon, Whiskey, and Timbalier Islands, all to their minimal geomorphologic form and ecologic function.

10

Raccoon (Plan B) /Trinity (Plan B) / East(Plan B) / Whisky (Plan B)/ Timbalier (Plan B)/ East Timbalier (Plan B) /Wine w/ Monkey(Plan B)

System-wide

Barrier Island

Restoration

1,842 439,000,000 22,420,000 12,170

Restoration of Raccoon, Whiskey, Trinity, East, Wine,Timbalier, and East Timbalier Islands, all to their minimalgeomorphologic form and ecologic function.

BW: BreakwatersTG: Terminal Groin* Refined cost accounts for potential reductions due to shared mobilization/demobilization as well as other fixed costs as described in Section L9.1.4

** Preliminary costs were annualized at a discount rate of 4.375%, with a base year of 2012. The price level is 2009.


3-1

K3. COST EFFECTIVENESS AND INCREMENTAL COST

ANALYSES

K3.1 COST EFFECTIVENESS

Figure K3-1 presents a graph depicting the ten (10) alternatives that comprise the

Intermediate Array of Alternatives categorized as non cost effective, cost effective and

Best Buy. The cost effective and Best Buy Plans are the alternatives that produce the

most benefits for the same or less cost. Note that the cost effective and Best Buy Plans

fall along the efficient frontier. The costs presented are preliminary costs which were

annualized at a discount rate of 4.375%, with a base year of 2012. The price level is

2009.

Figure K3-1. Results of IWR Iteration 2 Using the Intermediate Array of Alternatives

The CE/ICA analysis revealed that Alternatives 6, 7, 8, and 10 were not cost effective

when compared to the other alternatives in the Intermediate Array. Alternatives 6, 7, and

8 provide 785, 808, and 801 net AAHUs at a preliminary cost of $177,000,000,

$182,000,000, and $180,000,000, respectively. However, Alternative 2 provides more

benefits (871 AAHUs) for less preliminary cost ($170,000,000). Therefore, Alternatives

6, 7, and 8 are not cost effective when compared to Alternative 2. Similarly, Alternative

10 provides fewer benefits (1842 AAHUs) than Alternative 5 (2063 AAHUs) at a greater

preliminary cost and was therefore not cost effective.

Alt 5

Alt 10

Alt 4

Alt 3

Alt 9

Alt 2

Alt 6, 8, 7


3-2

Although there is a general positive sloping trend between costs and outputs (i.e.

benefits), the trend is not completely linear. A combination of factors contribute to this

non-linearity including number of islands in the alternative, characteristics of the existing

island footprints, and the extent to which the islands are being restored. For example,

Alternative 2 consists of restoring Timbalier Island (the largest island in the system)

using the largest island plan (Plan E). Alternatives 6, 7, and 8 will restore three smaller

islands (Raccoon, Whiskey, and Trinity) using smaller island plans (Plan B). These

alternatives will require three separate mobilization/demobilization events (compared to

just one for Alternative 2), considerably increasing the costs per benefit. Furthermore,

Timbalier Island currently has a considerable amount of sub-aerial habitat and a shallow

sloping subtidal region behind the island. Therefore, the restoration plan will require

relatively less material to increase its habitat value when compared to Alternatives 6, 7,

and 8 which will require fill placement in deeper water.

This phenomenon can also be seen when comparing Alternative 5 to Alternative 10.

Although Alternative 5 is only restoring four islands (compared to seven islands in

Alternate 10), it will produce a larger amount of AAHUs. This is because the islands in

Alternative 5 are being restored using larger plans (Plan E for Raccoon and Timbalier and

Plan C for Whiskey and Trinity) than Alternative 10, which restores the islands to the

minimum plan (Plan B). Furthermore, the additional mobilization/ demobilization costs

associated with a seven-island plan also increase the cost per benefit.

Table K3-1 displays the six (6) cost effective / Best Buy Plans from the Intermediate

Array of Alternatives.

Table K3-1. Cost Effective Alternatives

Code Description

Outputs

(AAHU)

Annualized

Cost ($)

Annualized

Cost/ AAHU

Alt 1 No Action (Plan A) 0 0 0

Alt 2 Timbalier (Plan E) 871 8,710,000 10,000

Alt 9 Raccoon (Plan B) / Whiskey (Plan B) /

Timbalier (Plan B) 890 10,160,000 11,410

Alt 3 Whiskey (Plan C) / Timbalier (Plan E) 1250 12,640,000 10,120

Alt 4 Whiskey (Plan C) / Trinity (Plan C) /

Timbalier (Plan E) 1637 16,820,000 10,280

Alt 5 Raccoon with TG (Plan E) / Whiskey (Plan C)

/ Trinity (Plan C) / Timbalier (Plan E) 2063 20,830,000 10,100

K3.2 INCREMENTAL COST ANALYSIS

The incremental cost analyses process is an iterative process. For the incremental cost

analysis, the cost effective alternative plans were sorted in order of increasing output

(Table K3-2). Next, the plan with the lowest average annual cost per AAHU beyond the

No-Action Plan (Alternative 1) was identified and selected as the first Best Buy Plan.


3-3

The process continued, searching for the greatest increases in output for the least

increases in cost. The alternatives were analyzed in all possible combinations.

Table K3-2. Incremental Cost Analysis

Code Outputs

(AAHU)

Total

Cost

($)

Additional

Output

(AAHU)

Additional

Costs

($)

Incremental

Costs

($/AAHU)

Category

Alt 1 0 0 - - 0 Best Buy

Alt 2 871 170,000,000 871 170,000,000 195,000 Best Buy

Alt 9 890 199,000,000 19 29,000,000 1,530,000 Cost

Effective

Alt 3 1,250 247,000,000 360 48,000,000 133,000 Cost

Effective

Alt 4 1,637 329,000,000 387 82,000,000 212,000 Cost

Effective

Alt 5 2,063 408,000,000 426 79,000,000 185,000 Best Buy

A graphical representation of the incremental analysis for the Best Buy Plans excluding

the No Action Plan is provided in Figure K3-1. As seen in the figure, Alternative 5

provides considerably more output for a slight increase in incremental cost.

Figure K3-2. Incremental Cost and Output for the Best Buy Plans.


3-4

As demonstrated by the CE/ICA, the incremental cost from Alternative 2 to Alternative 9

is not justifiable, thus Alternative 9 was not carried forward. Consequently, the PDT

narrowed the alternative selection to create the Final Array of Alternatives:

Alternative 1: No Action Plan;

Alternative 2: Timbalier (Plan E);

Alternative 3: Whiskey (Plan C)/Timbalier (Plan E);

Alternative 4: Whiskey (Plan C)/Trinity (Plan C)/Timbalier (Plan E);

Alternative 5: Raccoon with TG (Plan E)/Whiskey (Plan C)/Trinity (Plan

C)/Timbalier (Plan E); and

Alternative 11: Whiskey (Plan C)

In summary, these alternatives were carried forward for detailed analysis because they

were all cost effective and fell along the efficient frontier curve. Alternatives 6, 7, 8, and

10 were not cost effective and therefore, not carried forward for further analysis.

Alternative 9 was also removed from further analysis because the cost per AAHU was

significantly (14%) higher than Alternative 2 and it fell above the efficient frontier curve.

Alternative 11 was added to the Final Array because none of the alternatives in the

Intermediate Array were within Water Resources Development Act (WRDA) 2007

authorization for the LCA TBBSR Study. Discussion of the development and selection

of Alternative 11 is included in Section K5. Additional details are presented in the

Integrated Feasibility Study and Final Environmental Impact Statement Report, Section 3.


4-1

K4. NATIONAL ECOSYSTEM RESTORATION PLAN

K4.1 SELECTION OF THE NATIONAL ECOSYSTEM RESTORATION PLAN

To develop the National Ecosystem Restoration Plan (NER) Plan, the Final Array of

Alternatives identified in the previous section was used in a second IWR run. For this

run, net AAHUs and annualized costs were utilized. Additional details on the screening

analysis to select the NER Plan are presented in the Integrated Feasibility Study and Final

Environmental Impact Statement Report, Section 3.

Alternative 1

This alternative is the No Action Plan. It is one of the three Best Buy alternatives. Its net

AAHUs and cost are zero. The alternative was not selected as the NER Plan because the

barrier islands will continue to be subjected to the factors and processes that are

contributing to the eventual loss of the Timbalier Islands and the Isles Dernieres to open

water.

Alternative 2

This alternative is Plan E on Timbalier Island. It is one of the three Best Buy alternatives.

The alternative was not selected as the NER Plan because it only allows restoring one

island and thus does not achieve all of the Study goals and objectives especially

systematic ecosystem restoration for the whole basin. The remaining barrier islands will

continue to be subjected to the factors and processes that are contributing to the eventual

loss of the barrier islands to open water.

Alternative 3

This alternative is a combination of Plan C on Whiskey Island and Plan E on Timbalier

Island. It is a cost effective alternative. The alternative was not selected as the NER Plan

because it is not a Best Buy and only allows restoration of two islands.

Alternative 4

This alternative is a combination of Plan Cs on Whiskey and Trinity Islands and Plan E

on Timbalier Island. It is a cost effective alternative and geared toward a system-wide

approach. The alternative was not selected as the NER Plan because it is not a Best Buy.

Alternative 5

This alternative is a combination of Plan E with a TG on Raccoon Island, Plan Cs on

Whiskey and Trinity Islands and Plan E on Timbalier Island. It is one of the three Best

Buy alternatives, is geared toward a system-wide approach, and thus was selected as the

NER Plan. It also provides considerably more output for a slight increase in incremental

cost compared to the other Best Buy Plan (Alternative 2).

The design parameters for the NER Plan islands for the beach/dune fill and marsh fill are

presented in Tables K4-1 and K4-2, respectively. The borrow areas identified for the

NER Plan islands and the approximate required beach/dune and marsh cut volumes are


4-2

presented in Table K4-3. The borrow area and island restoration plans are presented in

Annexes L-1 and L-2, respectively.

Table K4-1. NER Plan Beach and Dune Fill Design Parameters

Island Plan Volume

(cy)

Length

(ft)

Density

(cy/lf)

Dune

(TY 1 acres)

Supratidal

(TY 1 acres)

Whiskey C 8,330,215 19,763 422 65 830

Trinity C 3,100,027 23,961 129 129 456

Raccoon w/ TG E 5,192,133 15,325 339 63 688

Timbalier E 10,702,818 39,106 274 215 2346

Table K4-2. NER Plan Marsh Fill Design Parameters

Island Plan Volume

(cy)

Length

(ft)

Density

(cy/lf)

Intertidal

(TY 1 acres)

Whiskey C 579,724 4,571 127 377

Trinity C 3,965,791 22,316 178 564

Raccoon w/ TG E 5,108,660 12,398 412 38

Timbalier E 9,073,317 35,433 256 69

Table K4-3. NER Plan Preliminary Assessment of Borrow Areas and Cut Volumes

Borrow Area Beach/Dune Cut

Volume (cy)

Marsh Cut

Volume (cy)

South Pelto Borrow Area 6 19,373,663 -

Ship Shoal Borrow Area 7 30,503,265 -

Whiskey Island Restoration Borrow Area 3 - 7,797,307

New Cut Borrow Area 4 - 2,300,000

Raccoon Island Restoration Borrow Area 5 - 2,200,000

The NER Plan was designed to create 2,063 net AAHUs at a preliminary opinion of cost

of approximately $408,000,000. The NER Plan represents a system-wide and cost

effective approach to restoring as many islands as possible within the Study Area that can

be constructed with cleared sediment sources.

K4.2 RENOURISHMENT CYCLES

In order to maintain the NER Plans geomorphic form through the 50-year period of

analysis, an analysis was conducted to determine the optimal renourishment cycle for

each island. The criterion to provide for geomorphologic sustainability of an island was

established as its non-breaching width. The island will not breach and lose its

geomorphologic form if its beach width exceeds the amount of erosion resulting from the

design storm impacts. Based on the modeling results presented in Annex L-3, of the three

design storms, Katrina & Rita combined event, Gustav & Ike combined event, and a 50-

year storm, the Katrina & Rita event resulted in the largest beach erosion amount of 104

ft (assuming 0.16 mm grain size) which was therefore selected as the critical nonbreaching beach width. Additional details on the incremental analysis to verify the NER

Plan remained cost effective with renourishment compared to the other alternatives are


4-3

presented in the Integrated Feasibility Study and Final Environmental Impact Statement

Report, Section 3.

K4.2.1 Whiskey Island

Table K4-4 presents Whiskey Island Plan C dune, supratidal, intertidal acres, beach

length, and average beach width corresponding to several TYs. It indicates that between

TY25 and TY30 Whiskey Island supratidal habitat disappears and only intertidal is

sustained for the 50-year period of analysis. Thus, the islands geomorphic form will

primarily be a submerged shoal from TY30 to TY50.

Table K4-4. Whiskey Island Plan C: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY15 TY20 TY25 TY30 TY40 TY50

Dune

Acres 0 65 61 57 2 0 0 0 0 0

Supratidal

Acres 377 830 328 223 162 84 4 0 0 0

Intertidal

Acres 443 377 808 828 855 847 837 717 472 363

Beach

Length, ft 11200 19800 19800 19800 19800 16500 3100 0 0 0

Beach

Width, ft 14661 1826 722 491 356 222 56 0 0 0

1 Includes CWPPRA TE-50 project.

An analysis of Whiskey Islands length and width indicated that by TY25 the island will

have breached, because its width of 56 ft is less than the critical non-breaching width of

104 ft. The islands projected beach length at TY25, 3,100 ft, compared to 18,100 ft of

beach at TY1, further confirms that Whiskey Island will have been breached between

TY20 and TY25. This analysis infers that Whiskey Island has to be renourished prior to

TY25.

In order to develop a minimal renourishment plan required to maintain Whiskey Islands

geomorphologic form and ecologic function for the entire 50-year period of analysis,

several renourishment alternatives (RA) were considered including:

RA1  renourishment of beach and dune at TY20 to add Plan C and TY40 to add

Plan C;

RA2  renourishment of beach and dune at TY20 to add Plan C and TY40 to add

Plan B; and

RA3  renourishment of beach and dune at TY15 to add Plan B and TY30 to add

Plan B.

Marsh renourishment was eliminated as the initial restoration plan provides for

significant intertidal habitat throughout the 50-year period of analysis, thus its evolution

over time remained the same as the initial Plan C restoration.


4-4

Below is a description of RA1, renourishment of beach and dune at TY20 to add Plan C

and TY40 to add Plan C, the other two alternatives were analyzed in a similar manner.

Renourishment of Whiskey Islands beach and dune portions at TY20 to add Plan C

infers retaining what is left of the island at TY20 from its initial Plan C restoration and

adding the same amount of beach and dune acres developed for TY1. Further, because a

portion of the initial restoration supratidal acres will convert to intertidal acres by TY20

as a result of sea level rise and subsidence, only the portion of initially supratidal acres

that remains supratidal at TY20 gets added during beach renourishment.

After renourishment at TY20, beach and dune acres were evolved such that at TY40, the

beach/dune acres are a summation of beach/dune acres from initial restoration of

Whiskey Island that are still remaining 40 years later and beach/dune acres of the TY20

renourishment still remaining 20 years after that renourishment. The latter is equivalent

to initial Plan Cs dune/beach acres at TY20.

Tables K4-5 through K4-7 present dune, supratidal, intertidal acres, beach length, and

average beach width developed for the three RAs on Whiskey Island.

Table K4-5. Whiskey Island RA1: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY21 TY30 TY40 TY41 TY50

Dune

Acres 0 65 61 57 0 65 57 0 65 57

Supratidal

Acres 377 830 328 223 84 4961 223 84 4961 223

Intertidal

Acres 443 377 808 828 847 834 717 472 461 363

Beach

Length, ft 11200 19800 19800 19800 16500 19800 19800 16500 19800 19800

Beach

Width, ft 14662 1826 722 491 222 1091 491 222 1091 491

1 Plan C Supratidal Beach = 412 Acres (these supratidal acres are part of renourishment),

Plan C Supratidal Marsh = 418 Acres (these supratidal acres are not part of renourishment). 2 Includes CWPPRA TE-50 project.


4-5

Table K4-6. Whiskey Island RA2: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY21 TY30 TY40 TY41 TY50

Dune

Acres 0 65 61 57 0 65 57 0 57 0

Supratidal

Acres 377 830 328 223 84 4961 223 84 3872 164

Intertidal

Acres 443 377 808 828 847 834 717 472 461 363

Beach

Length, ft 11200 19800 19800 19800 16500 19800 19800 16500 19600 19600

Beach

Width, ft 14663 1826 722 491 222 1091 491 222 860 364

1 Plan C Supratidal Beach = 412 Acres (these supratidal acres are part of renourishment),

Plan C Supratidal Marsh = 418 Acres (these supratidal acres are not part of renourishment). 2 Plan B Supratidal Beach = 303 Acres (these supratidal acres are part of renourishment),

Plan B Supratidal Marsh = 311 Acres (these supratidal acres are not part of renourishment). 3 Includes CWPPRA TE-50 project.

Table K4-7. Whiskey Island RA3: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY15 TY16 TY20 TY30 TY31 TY40 TY50

Dune

Acres 0 65 61 57 2 59 53 27 84 0 0

Supratidal

Acres 377 830 328 223 162 4651 304 82 385 164 0

Intertidal

Acres 443 377 808 828 855 853 847 717 693 472 363

Beach

Length, ft 11200 19800 19800 19800 19800 19600 19600 19600 19600 19600 0

Beach

Width, ft 14662 1826 722 491 356 1033 676 180 856 364 0

1 Plan B Supratidal Beach = 303 Acres (these supratidal acres are part of renourishment),

Plan B Supratidal Marsh = 311 Acres (these supratidal acres are not part of renourishment). 2 Includes CWPPRA TE-50 project.

Figure K4-1 presents a graphical summary of dune and beach acres associated with initial

restoration Plan C and the three RAs for the 50-year period of analysis.

Based on the RA analysis, RA1 and RA2 sustain geomorphologic form throughout the

period of analysis, however, RA3 does not. Because RA2 requires renourishment at

TY40 in the form of adding Plan B which is smaller than Plan C added at TY40 in RA1,

RA2 is a less expensive RA to implement and thus was selected.


4-6

0

100

200

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40 45 50

Dune - Plan C

Dune - Plan C w/ Renourish. at TY20 (add Plan C) and TY40 (add Plan C)

Dune - Plan C w/ Renourish. at TY20 (add Plan C) and TY40 (add Plan B)

Dune - Plan C w/ Renourish. at TY15 (add Plan B) and TY30 (add Plan B)

Supratidal - Plan C

Supratidal - Plan C w/ Renourish. at TY20 (add Plan C) and TY40 (add Plan C)

Supratidal - Plan C w/ Renourish. at TY20 (add Plan C) and TY40 (add Plan B)

Supratidal - Plan C w/ Renourish. at TY15 (add Plan B) and TY30 (add Plan B)

Figure K4-1. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan C and Three Renourishment Alternatives on Whiskey Island.

K4.2.2 Trinity Island

Table K4-8 presents Trinity Island Plan C dune, supratidal, intertidal acres, beach length,

and average beach width for a range of TYs. It indicates that between TY30 and TY40

Trinity Island supratidal habitat disappears and only intertidal is sustained for the 50-year

period of analysis. Thus, the islands geomorphic form will primarily be a submerged

shoal from TY30 to TY50.

Table K4-8. Trinity Island Plan C: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY15 TY20 TY25 TY30 TY40 TY50

Dune

Acres 39 129 122 67 34 0 0 0 0 0

Supratidal

Acres 232 456 316 270 230 190 90 4 0 0

Intertidal

Acres 311 564 632 635 615 594 597 561 380 199

Beach

Length, ft 22600 24000 24000 24000 24000 24000 22400 4100 0 0

Beach

Width, ft 447 828 574 490 417 345 175 42 0 0

An analysis of Trinity Islands length and width indicated island breaching will have

occurred by TY30 as only four (4) supratidal acres with a projected beach width of 42 ft,

significantly less than the non-breaching beach width of 104 ft derived from the

SBEACH storm impact modeling, remain. Further, as a result of breaching, the length of

Trinity Island will have reduced by 83% at TY30 compared to its restored length at TY1.

At TY25, the islands beach is projected to be 175 ft wide and non-breaching which


4-7

infers that Plan C on Trinity Island will sustain geomorphologic form for 25 years and the

island has to then be renourished to maintain the form for the remaining 25 years of

analysis.

Because Plan B is smaller than Plan C using Plan B to renourish Trinity Island at TY25

will not be sufficient for 25 years of sustainability between TY26 and TY50 without a

second renourishment event. Plans D and E are, on the other hand, larger than Plan C and

will be sufficient but are more expensive to implement. Therefore, adding Plan C at

TY25 is the optimal RA, thus it was selected.

Renourishment of Trinity Islands beach and dune portions at TY25 to add Plan C infers

retaining what is left of the island at TY25 from its initial Plan C restoration and adding

the same amount of beach and dune acres developed for TY1. Because a portion of the

initial restoration supratidal acres will convert to intertidal acres by TY25 as a result of

sea level rise and subsidence, only the portion of initially supratidal acres that remains

supratidal at TY25 gets added during renourishment.

After renourishment at TY25, beach and dune acres were evolved such that at TY30, the

beach/dune acres are a summation of beach/dune acres from initial restoration of Trinity

Island that are still remaining 30 years later and beach/dune acres of the TY25

renourishment still remaining 5 years after that renourishment. The latter is equivalent to

initial Plan Cs beach/dune acres at TY5. For TY40 and TY50, the beach and dune acres

were evolved in a similar manner.

Similarly to Whiskey Island, marsh renourishment on Trinity Island was eliminated as

the initial restoration plan provides for significant intertidal habitat throughout the 50-

year period of analysis.

Table K4-9 presents dune, supratidal, intertidal acres, beach length, and average beach

width developed for the renourishment scenario on Trinity Island.

Table K4-9. Trinity Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY15 TY20 TY25 TY26 TY30 TY40 TY50

Dune

Acres 39 129 122 67 34 0 0 129 122 34 0

Supratidal

Acres 232 456 316 270 230 190 90 4961 320 230 90

Intertidal

Acres 311 564 632 635 615 594 597 590 561 380 199

Beach

Length, ft 22600 24000 24000 24000 24000 24000 22400 24000 24000 24000 22400

Beach

Width, ft 447 828 574 490 417 345 175 900 581 417 175

1 Plan C Supratidal Beach = 406 Acres (these supratidal acres are part of renourishment),

Plan C Supratidal Marsh = 50 Acres (these supratidal acres are not part of renourishment).


4-8

Figure K4-2 presents a graphical summary of beach and dune acres associated with initial

restoration Plan C and recommended renourishment scenario for the 50-year period of

analysis.

0

100

200

300

400

500

600

0 5 10 15 20 25 30 35 40 45 50

Dune - Plan C

Dune - Plan C w/ Renourish. at TY25 to Add Plan C

Supratidal - Plan C

Supratidal - Plan C w/ Renourish. at TY25 to Add Plan C

Figure K4-2. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan C and Recommended Renourishment Scenario on Trinity Island.

K4.2.3 Raccoon Island with Terminal Groin

Table K4-10 presents Raccoon Island Plan E with TG habitat acres and island dimensions

calculated for a range of TYs. It indicates that the supratidal habitat is sustained for the

50-year period of analysis. However, an analysis of Raccoon Islands beach dimensions

indicates that the length of Raccoon Islands beach will have reduced by 54% by TY40

and by 65% by TY50 compared to its restored length at TY1. This infers that the island

has to be renourished at TY30 to maintain its geomorphologic form for the remaining 20

years of analysis.

Table K4-10. Raccoon Island Plan E with Terminal Groin: Island Acres and Beach

Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Dune Acres 0 63 50 29 20 0 0 0

Supratidal

Acres 51 688 678 659 650 182 106 66

Intertidal

Acres 188 38 39 40 39 466 486 468

Beach

Length, ft 8200 15300 15300 15300 15300 15300 7000 5400

Beach

Width, ft 271 1959 1930 1876 1851 518 660 532


4-9

In order to develop a minimal renourishment plan required to maintain Raccoon Islands

geomorphologic form and ecologic function, two renourishment alternatives (RA) were

considered including:

RA1  renourishment of beach and dune at TY30 to restore Plan B; and

RA2  renourishment of beach and dune at TY30 to add Plan B.

Marsh renourishment was eliminated as the initial restoration plan provides for

significant intertidal habitat throughout the 50-year period of analysis, thus its evolution

over time remained the same as the initial Plan E restoration.

For RA1, renourishment of beach and dune at TY30 to restore Plan B infers building Plan

B on what is left of the island at TY30 from its initial Plan E restoration to create Plan

Bs amount of beach and dune acres developed for TY1. Because a portion of the initial

restoration supratidal acres will convert to intertidal acres by TY30 as a result of sea level

rise and subsidence, only the portion of initially supratidal acres that remains supratidal at

TY30 gets restored during beach renourishment.

For RA2, renourishment of beach and dune at TY30 to add Plan B infers retaining what

is left of the island at TY30 from its initial Plan E restoration and adding Plan Bs amount

of beach and dune acres developed for TY1. Similarly to RA1, only the portion of

initially supratidal acres that remains supratidal at TY30 gets added during beach

renourishment.

Tables K4-11 and K4-12 present dune, supratidal, intertidal acres, beach length, and

average beach width developed for the two RAs on Raccoon Island.

Table K4-11. Raccoon Island RA1: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY30 TY31 TY40 TY50

Dune

Acres 0 63 50 29 20 0 45 15 3

Supratidal

Acres 51 688 678 659 650 182 2041 165 170

Intertidal

Acres 188 38 39 40 39 466 468 486 468

Beach

Length, ft 8200 15300 15300 15300 15300 15300 14900 14900 14900

Beach

Width, ft 271 1959 1930 1876 1851 518 596 482 497

1 Plan B Supratidal Beach = 204 Acres (these supratidal acres are part of renourishment),

Plan B Supratidal Marsh = 23 Acres (these supratidal acres are not part of renourishment).


4-10

Table K4-12. Raccoon Island RA2: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY30 TY31 TY40 TY50

Dune

Acres 0 63 50 29 20 0 45 15 3

Supratidal

Acres 51 688 678 659 650 182 3861 271 236

Intertidal

Acres 188 38 39 40 39 466 468 486 468

Beach

Length, ft 8200 15300 15300 15300 15300 15300 14900 14900 14900

Beach

Width, ft 271 1959 1930 1876 1851 518 1128 792 690

1 Plan B Supratidal Beach = 204 Acres (these supratidal acres are part of renourishment),

Plan B Supratidal Marsh = 23 Acres (these supratidal acres are not part of renourishment).

Figure K4-3 presents a graphical summary of beach and dune acres associated with initial

restoration Plan E and the two RAs for the 50-year period of analysis.

Based on the RA analysis, both RA1 and RA2 sustain geomorphologic form throughout

the period of analysis; however, RA1 requires renourishment in the form of restoring

Plan B which is smaller than adding Plan B. Therefore RA1 is a less expensive RA to

implement and thus was selected.

0

100

200

300

400

500

600

700

800

0 5 10 15 20 25 30 35 40 45 50

Dune AAHUs - Plan E

Dune - Plan E w/ Renourish. at TY30 (restore Plan B)

Dune - Plan E w/ Renourish. at TY30 (add Plan B)

Supratidal - Plan E

Supratidal - Plan E w/ Renourish. at TY30 (restore Plan B)

Supratidal - Plan E w/ Renourish. at TY30 (add Plan B)

Figure K4-3. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan E and Two Renourishment Alternatives on Raccoon Island.


4-11

K4.2.4 Timbalier Island

Table K4-13 presents Timbalier Island Plan E habitat acres and island dimensions

calculated for the 50-year period of analysis. It indicates that the supratidal habitat is

sustained for the 50-year period of analysis. However, an analysis of Timbalier Islands

beach dimensions indicates that the width of Timbalier Islands beach will have

decreased from 406 ft TY40 to 65 ft at TY50 which is significantly less that the nonbreaching width of 104 ft. This infers that the island will no longer sustain its

geomorphologic form and function and will have to be renourished by TY40. However,

the volumes associated with renourishment of Timbalier Island are minor compared to

initial restoration. Thus, to remain cost effective, TY30 was selected to coincide with the

renourishment event on Raccoon Island so the two islands could be constructed under a

single mobilization.

Table K4-13. Timbalier Island Plan E: Island Acres and Beach Dimensions

Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY30 TY40 TY50

Dune Acres 57 215 183 160 0 0 0 0

Supratidal

Acres 549 2346 2257 2130 1996 629 330 53

Intertidal

Acres 374 69 71 74 76 1148 1123 1088

Beach

Length, ft 35600 39100 39100 39100 39100 37700 35400 35400

Beach

Width, ft 672 2614 2514 2373 2224 727 406 65

In order to develop a minimal renourishment plan required to maintain Timbalier Islands

geomorphologic form and ecologic function, two RAs were considered including:

RA1  renourishment of beach and dune at TY30 to restore Plan B; and

RA2  renourishment of beach and dune at TY30 to add Plan B.

Marsh renourishment was eliminated as the initial restoration plan provides for

significant intertidal habitat throughout the 50-year period of analysis, thus its evolution

over time remained the same as the initial Plan E restoration.

For RA1, renourishment of beach and dune at TY30 to restore Plan B infers building Plan

B on what is left of the island at TY30 from its initial Plan E restoration to create Plan

Bs amount of beach and dune acres developed for TY1. Because a portion of the initial

restoration supratidal acres will convert to intertidal acres by TY30 as a result of sea level

rise and subsidence, only the portion of initially supratidal acres that remains supratidal at

TY30 gets restored during renourishment.

For RA2, renourishment of beach and dune at TY30 to add Plan B infers retaining what

is left of the island at TY30 from its initial Plan E restoration and adding Plan Bs amount


4-12

of beach and dune acres developed for TY1. Similarly to RA1, only the portion of

initially supratidal acres that remains supratidal at TY30 gets added during beach

renourishment.

Tables K4-14 and K4-15 present dune, supratidal, intertidal acres, beach length, and

average beach width developed for the two RAs on Timbalier Island.

Table K4-14. Timbalier Island RA1: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY30 TY31 TY40 TY50

Dune

Acres 57 215 183 160 0 0 155 13 0

Supratidal

Acres 549 2346 2257 2130 1996 629 6671 524 236

Intertidal

Acres 374 69 71 74 76 1148 1146 1123 1088

Beach

Length, ft 35600 39100 39100 39100 39100 37700 35400 39100 39100

Beach

Width, ft 672 2614 2514 2373 2224 727 821 584 263

1 Plan B Supratidal Beach = 667 Acres (these supratidal acres are part of renourishment),

Plan B Supratidal Marsh = 81 Acres (these supratidal acres are not part of renourishment).

Table K4-15. Timbalier Island RA2: Island Acres and Beach Dimensions Summary

Target

Year TY0 TY1 TY5 TY10 TY20 TY30 TY31 TY40 TY50

Dune

Acres 57 215 183 160 0 0 155 13 0

Supratidal

Acres 549 2346 2257 2130 1996 629 12961 854 289

Intertidal

Acres 374 69 71 74 76 1148 1146 1123 1088

Beach

Length, ft 35600 39100 39100 39100 39100 37700 35400 39100 39100

Beach

Width, ft 672 2614 2514 2373 2224 727 1595 951 322

1 Plan B Supratidal Beach = 667 Acres (these supratidal acres are part of renourishment),

Plan B Supratidal Marsh = 81 Acres (these supratidal acres are not part of renourishment).

Figure K4-4 presents a graphical summary of beach and dune acres associated with initial

restoration Plan E and the two RAs for the 50-year period of analysis.

Based on the RA analysis, both RA1 and RA2 sustain geomorphologic form throughout

the period of analysis; however, RA1 requires renourishment in the form of restoring

Plan B which is smaller than adding Plan B. Therefore RA1 is a less expensive RA to

implement and thus was selected.


4-13

0

500

1000

1500

2000

2500

0 5 10 15 20 25 30 35 40 45 50

Dune - Plan E

Dune - Plan E w/ Renourish. at TY30 to Restore Plan B

Dune - Plan E w/ Renourish. at TY30 to Add Plan B

Supratidal - Plan E

Supratidal - Plan E w/ Renourish. at TY30 to Restore Plan B

Supratidal - Plan E w/ Renourish. at TY30 to Add Plan B

Figure K4-4. Graphical Summary of Dune and Beach Acres Associated with Initial

Restoration Plan E and Two Renourishment Alternatives on Timbalier Island.

K4.3 DESCRIPTION OF NATIONAL ECOSYSTEM RESTORATION PLAN WITH

RENOURISHMENT

The iterative analyses resulted in recommending Alternative 5 with renourishment as the

NER Plan. The NER Plan with renourishment consists of restoration of:

Whiskey Island to its minimal geomorphologic form and ecologic function along

with 5 years of advanced fill (Plan C) and two beach and dune renourishment

events, one at TY20 to add Plan C and the other one at TY40 to add Plan B;

Trinity Island to its minimal geomorphologic form and ecologic function along

with 5 years of advanced fill (Plan C) and one renourishment of beach and dune at

TY25 to add Plan C;

Raccoon Island to its minimal geomorphologic form and ecologic function along

with 25 years of advanced fill, construction of a TG on the western end, and one

renourishment of beach and dune at TY30 to restore Plan B; and

Timbalier Island to its minimal geomorphologic form and ecologic function along

with 25 years of advanced fill and one renourishment of beach and dune at TY30

to restore Plan B.

The NER Plan with renourishment was designed to create 2,883 net AAHUs. The design

beach/dune fill and marsh fill parameters are presented in Table K4-16. The borrow areas

identified for the NER Plan with renourishment and the required approximate beach/dune

and marsh cut volumes are presented in Table K4-17. Further, the borrow area and island

restoration plans are presented in Annexes L-1 and L-2, respectively.


4-14

Table K4-16. NER Plan Beach / Dune Fill and Marsh Fill Design Parameters

Fill Volume

(cy)

Length

(ft)

Density

(cy/lf)

Dune

Acres

Supratidal

Acres

Intertidal

Acres

Beach/Dune 27,320,000 98,200 278 4721 4,3201 N/A

Initial

Marsh 18,730,000 74,800 250 N/A N/A 10481

TY20 8,330,000 19,800 422 652 4962 8342

TY25 3,100,000 24,000 129 1293 4963 5903

TY30 2,420,000 54,000 45 2004 1,6824 1,5914

Renourishment

TY40 6,330,000 19,600 323 575 3875 4615

1 at TY1; 2 at TY21; 3 at TY26; 4 at TY31; 5 at TY41

N/A denotes Not Applicable

Table K4-17. NER Plan Borrow Areas and Cut Volumes

Borrow Area

Beach/Dune

Cut Volume

(cy)

Marsh Cut

Volume (cy)

Ship Shoal Borrow Area 7 19,800,000 3,160,000

South Pelto Borrow Area 6 12,090,000 3,480,000

Whiskey Island Restoration Borrow Area 3  12,400,000

New Cut Borrow Area 4  2,500,000

Initial

Raccoon Island Restoration Borrow Area 5  2,400,000

Ship Shoal Borrow Area 7 23,100,000 

Renourishment

South Pelto Borrow Area 6 531,000 

The Tri-Services Automated Cost Engineering System (TRACES MII Version 3.01) was

used to develop the baseline LCA TBBSR Study cost for the NER Plan with

renourishment. MII is the second generation of the MCASES software used as a costing

tool by the USACE. The MII English Cost Book 2008, National Labor 2008 -

Preliminary Draft, and the MII Equipment Region 3r 2007 libraries were linked to the

project library in the development of the costs for the NER Plan with renourishment.


4-15

Based on the detailed cost estimate prepared and a contingency value determined using

Crystal Ball, a fully funded cost estimate of $689,000,000 was developed for the initial

restoration of the NER Plan. Utilizing the MII cost developed for the renourishment

events and a contingency of 35% based on professional judgment, the O&M costs for the

Raccoon Island TG at TY10 and renourishment events at TY20, TY25, TY30 and TY40

were estimated to be $1,370,000, $157,000,000, $117,000,000, $97,500,000, and

$184,000,000, respectively. The opinion of probable fully funded cost for the NER Plan

with renourishment is approximately $1,246,000,000. Refer to Appendix L for the

detailed cost estimate.


5-1

K5. FIRST COMPONENT OF CONSTRUCTION

K5.1 SELECTION OF THE FIRST COMPONENT OF CONSTRUCTION

The NER Plan which consists of Whiskey Plan C, Trinity Plan C, Raccoon Plan E with

TG, and Timbalier Plan E was selected based on the IWR analysis, it is a Best Buy that

fulfills the planning objectives of the LCA TBBSR Study, and it represents a systemwide and cost effective approach of restoring as many islands within the Terrebonne

Basin which can be constructed with cleared sediment sources. However, the NER Plan

cannot be constructed within WRDA 2007 authorization. In order to identify plans that

could be constructed within WRDA 2007 authorization, the PDT performed separate cost

refinements on each island in the NER Plan using MII. The original contingency was also

refined using Crystal Ball. These refinements inflated the costs of the islands, leaving

Trinity Island Plan C and Whiskey Island Plan C as the only island plans that could be

constructed within WRDA 2007 authorization. Consequently, a separate screening

process was conducted on the two islands to select the most appropriate island to be

constructed as the first component of construction.

Previous CE/ICA analysis revealed that both islands plans, when analyzed separately,

were cost effective. The plans also proved to be cost effective when analyzed by running

the IWR analysis on an extended array that included the original ten (10) alternatives plus

the two (2) additional alternatives (Table K5-1 and Figure K5-1). Renourishment was not

included in this analysis.

Although Whiskey Plan C provides slightly fewer net AAHUs than Trinity Island Plan C

(379 net AAHUs vs. 387 net AAHUs), it was determined to be the first component of

construction due to a number of qualitative benefits provided by the plan. For example,

Whiskey Plan C was designed to avoid approximately 286 acres of existing mangroves

on the island in order to minimize the ecologic impact during construction, and to protect

these habitats over time by constructing the beach and dune template gulf-ward. Since

the island is considered a valuable wildlife habitat (the Isles Dernieres Barrier Islands

Wildlife Refuge) and the Louisiana Department of Wildlife and Fisheries is

reestablishing a pelican rookery on the island, maintaining adequate areas of healthy

beach, dune, and marsh is particularly important. Whiskey Plan C was also designed to

complement TE-50, which is an existing CWPPRA project that was constructed in 2009.

TE-50 created approximately 316 acres of intertidal back-barrier marsh between the two

existing mangrove stands. Restoration of the beach and dune gulfward of TE-50 will

help to protect the existing CWPPRA investment.

Whiskey Island is also the closest island to the critical marsh habitat located in the

southern-most portion of Terrebonne Basin. If the island was to disappear, the marsh

habitat on the mainland would be susceptible to the direct impacts of tropical storms and

hurricanes.


5-2

Table K5-1. Summary of Extended Array of Restoration Plans

Alternative Category Net AAHU Preliminary Cost* ($) Annualized Cost** ($)

Annualized

Cost per

AAHU

($/AAHU)

Description

1 No Action (Plan A) No Action 0 0 0 0 This alternative does not include any restoration.2 Timbalier (Plan E) Best Buy 871 170,000,000 8,710,000 10,000

Restoration of Timbalier Island to its minimalgeomorphologic form and ecologic function along with 25years of advanced fill.

3 Whiskey (Plan C) / Timbalier (Plan E) Best Buy 1250 247,000,000 12,600,000 10,120

Restoration of Whiskey Island to its minimal geomorphologicform and ecologic function along with 5 years of advancedfill combined with restoration of Timbalier Island to itsminimal geomorphologic form and ecologic function alongwith 25 years of advanced fill.

4

Whiskey (Plan C) /Trinity (Plan C) /Timbalier (Plan E)

Best Buy 1637 329,000,000 16,800,000 10,280

Restoration of Whiskey and Trinity Islands to their minimalgeomorphologic form and ecologic function along with 5years of advanced fill combined with restoration of TimbalierIsland to its minimal geomorphologic form and ecologicfunction along with 25 years of advanced fill.

5

Raccoon with TG(Plan E) /Whiskey (Plan C) /Trinity (Plan C) /Timbalier (Plan E)

Best Buy 2063 408,000,000 20,800,000 10,100

Restoration of Whiskey and Trinity Islands to their minimalgeomorphologic form and ecologic function along with 5years of advanced fill combined with restoration of Raccoonand Timbalier Islands to their minimal geomorphologic formand ecologic function along with 25 years of advanced filland construction of a terminal groin on the western end ofRaccoon Island.

6

Raccoon (Plan B) /Whiskey (Plan B) /Trinity (Plan B)

Max # of Islands

Constructible with

Cleared Sediment

Sources

785 177,000,000 9,040,000 11,510 Restoration of Raccoon, Whiskey, and Trinity Islands, all to their minimal geomorphologic form and ecologic function.

7

Raccoon with BW(Plan B) /Whiskey (Plan B) /Trinity (Plan B)

Max # of Islands

Constructible with

Cleared Sediment

Sources

808 182,000,000 9,280,000 11,490

Restoration of Raccoon, Whiskey, and Trinity Islands, all totheir minimal geomorphologic form and ecologic function,along with construction of eight (8) additional breakwaters onthe western end of Raccoon Island.

8

Raccoon with TG (Plan B)

/ Whiskey (Plan B) /Trinity (Plan B)

Max # of Islands

Constructible with

Cleared Sediment

Sources

801 180,000,000 9,190,000 11,470

Restoration of Raccoon, Whiskey, and Trinity Islands, all totheir minimal geomorphologic form and ecologic function,along with construction of a terminal groin on the westernend of Raccoon Island.


5-3

Alternative Category Net AAHU Preliminary Cost* ($) Annualized Cost** ($)

Annualized

Cost per

AAHU

($/AAHU)

Description

9

Raccoon (Plan B) /Whiskey (Plan B) /Timbalier (Plan B)

Max # of Islands

Constructible with

Cleared Sediment

Sources

890 199,000,000 10,200,000 11,420 Restoration of Raccoon, Whiskey, and Timbalier Islands, all to their minimal geomorphologic form and ecologic function.

10

Raccoon (Plan B) /Trinity (Plan B) / East(Plan B) / Whisky (Plan B)/ Timbalier (Plan B)/ East Timbalier (Plan B) /Wine w/ Monkey(Plan B)

System-wide

Barrier Island

Restoration

1842 439,000,000 22,400,000 12,170

Restoration of Raccoon, Whiskey, Trinity, East, Wine,Timbalier, and East Timbalier Islands, all to their minimalgeomorphologic form and ecologic function.

11 Whiskey (Plan C) Partial NER Plan 379 79,600,000 4,070,000 10,740

Restoration of Whiskey Island to its minimal geomorphologicform and ecologic function along with 5 years of advancedfill.

12 Trinity (Plan C) Partial NER Plan 387 81,500,000 4,160,000 10,750

Restoration of Trinity Island to its minimal geomorphologicform and ecologic function along with 5 years of advancedfill.

BW: BreakwatersTG: Terminal Groin* Refined cost accounts for potential reductions due to shared mobilization/demobilization as well as other fixed costs as described in Section L9.1.4

** Preliminary costs were annualized at a discount rate of 4.375%, with a base year of 2012. The price level is 2009


5-4

Figure K5-1. Results of IWR Analysis Using the Extended Array

K5.2 RENOURISHMENT CYCLE

The first component of construction consists of restoration of Whiskey Island to its

minimal geomorphologic form and ecologic function along with 5 years of advanced fill.

The PDT re-evaluated the feasibility of renourishment on Whiskey Island Plan C. This

evaluation was conducted concurrently with that of the NER Plan (Section 4.2). Based

on an iterative optimization process, the PDT determined that Whiskey Plan C would

require two renourishment intervals. The first would occur at TY20 and would include

the addition of the same amount of dune and supratidal beach habitat that was originally

created in TY1 (i.e. add a Plan C to the template at TY20). The second renourishment

interval would occur at TY 40 and would include the addition of the same amount of

dune and supratidal beach habitat needed to construct a Plan B template. No additional

marsh material will be added.

K5.3 DESCRIPTION OF FIRST COMPONENT OF CONSTRUCTION WITH

RENOURISHMENT

The iterative analyses resulted in recommending Alternative 11 with renourishment as

the first component of construction. The plan consists of restoration of Whiskey Island to

its minimal geomorphologic form and ecologic function along with 5 years of advanced

fill (Plan C) and two renourishment events, one at TY20 to add Plan C and the other one

at TY40 to add Plan B. The plan was designed to create 678 net AAHUs.

Alt 5

Alt 10

Alt 4

Alt 3

Alt

Alt 2

Alt 6, 8, 7

Alt 11, 12


5-5

The design parameters for the first component of construction for the beach/dune fill and

marsh fill are presented in Table K5-2. The borrow areas identified for the first

component of construction and the required approximate beach/dune and marsh cut

volumes are presented in Table K5-3. Further, the borrow area and island restoration

plans are presented in Annexes L-1 and L-2, respectively.

Table K5-2. First Component of Construction Beach / Dune Fill and Marsh Fill

Design Parameters

Fill Volume

(cy)

Length

(ft)

Density

(cy/lf)

Dune

Acres

Supratidal

Acres

Intertidal

Acres

Beach/Dune 8,330,000 19800 422 651 8301 N/A

Initial

Marsh 580,000 4,600 127 N/A N/A 3771

TY20 8,330,000 19,800 422 652 4962 8342

Renourishment

TY40 6,330,000 19,600 323 573 3873 4613

1 at TY1

2 at TY21

3 at TY41

N/A denotes Not Applicable

Table K5-3. First Component of Construction Borrow Areas and Cut Volumes

Borrow Area

Beach/Dune

Cut Volume

(cy)

Marsh Cut

Volume (cy)

Ship Shoal Borrow Area 7 9,410,000 

Initial

Whiskey Island Restoration Borrow Area 3  928,000

Ship Shoal Borrow Area 7 16,600,000 

Renourishment

Whiskey Island Restoration Borrow Area 3  

Based on the detailed cost estimate prepared and a contingency value determined using

Crystal Ball, a fully funded cost estimate of $119,000,000 was developed for the initial

restoration of the first component of construction. Utilizing the MII cost developed for

the renourishment events and a contingency of 35% based on professional judgment the

renourishment events at TY20 and TY40 were estimated to cost $158,000,000 and

$184,000,000, respectively. The opinion of probable fully funded cost for the first

component of construction is approximately $461,000,000. Refer to Appendix L for the

detailed cost estimate.


LCA TERREBONNE BASIN BARRIER

SHORELINE RESTORATION STUDY

APPENDIX K

COST-EFFECTIVENESS/

INCREMENTAL COST ANALYSIS

ANNEX K-1

RESPONSES TO WVA COMMENTS



1

LCA Terrebonne Basin Barrier Shoreline Restoration Study

Responses to Wetland Value Assessment (WVA) Model Certification Comments.

1. Comment #1: Starting the SI curves for all variables at 0.1 is problematic because even

habitat with no ecological value appears to have some ecological value.

Response: The use of the 0.0 intercept would not affect the relative rankings of the alternatives

for the LCA Terrebonne Basin Barrier Shoreline Restoration Study (LCA TBBSR). The use of

an SI value starting at 0.1 is consistent with assumptions of similar habitat assessment methods

presently in use by the Natural Resources Conservation Service (NRCS). Reference NRCS

Biology Technical Note No. 51 and No 52 dated May 2005 and assumptions regarding wildlife

habitat appraisal guides:

"There is no minimum size for land to be appraised as wildlife habitat. However, tracts of 1 to 20

acres may be limited as habitat by their size alone. 1. All land and waters provide habitat for

wildlife. 2. The quality of habitat is variable depending on the quality, quantity, and

interspersion of food, cover, water, and space."

This response is consistent with responses previously provided to the ECO-PCX regarding

certification of the WVA Models by the US Fish and Wildlife Service (USFWS), other model

users, and the ERDC reviewers (McKay and Fischenich manuscript dated September 21, 2009);

see comments furnished in a document entitled Draft Model Certification Review Report for the

Wetland Value Assessment Models, dated July 8, 2009.

2. Comment #2. Justification for assigning variable weights needs to be provided.

Response: Justification for SI curves and aggregation equations is not included in the model

documentation. Aggregation formulas were originally developed based on existing literature and

professional judgment of model developers. Assumptions related to these aggregation formulas,

although originally developed based on existing literature and professional judgment of the

model developers, were not documented. In addition, aggregation formulas have been modified

based on lessons learned in model application. Assumptions of the WVA Model formulas

pertaining to the LCA TBBSR Study have been documented in the WVA Project Information

Sheet. A separate effort responding to the comments on the WVA Models is presently planned

by the New Orleans District to conduct a literature review by an interagency group and

contractor that would then utilize these references for adding supporting justification to the

model documentation. Revisions to the WVA Models would be considered if published

literature conflicts with the existing Suitability Indices. In addition, sensitivity analysis on the

weightings would also be considered. This response is consistent with responses previously

provided to the ECO-PCX regarding certification of the WVA Models by the US Fish and

Wildlife Service (USFWS), other model users, and the ERDC reviewers (McKay and Fischenich

manuscript dated September 21, 2009); see comments furnished in a document entitled Draft

Model Certification Review Report for the Wetland Value Assessment Models, dated July 8,

2009.


2

3. Comment #3: The number of Target Years should be increased to improve the predictive

ability of the models given that changes are often non-linear.

Response: For the LCA TBBSR Study, different alternatives were analyzed using different

Target Years depending upon various assumptions such as vegetation planting and

establishment, renourishment, and others. This and other assumptions are described in the

Project Information Sheet prepared for this Study. Target Years represent points within the Study

period of analysis when habitat conditions in the Study area are expected to change (e.g., storms,

increasing salinity, restoration implementation, maintenance, increase in vegetative cover, etc).

Changes between Target Years are assumed to be linear; which is consistent with assumptions of

HEP models.

4. Comment #4: In the spreadsheet for the marsh models, open water and emergent marsh

AAHUs are incorrectly combined and should be added rather than taking the weighted

arithmetic mean (model issue).

Response: The higher weighting of the marsh benefits was incorporated to ensure that benefits

to wetlands, not open water, clearly provide the driving force behind benefits. It seems more

obvious and transparent to the user to apply an adjustment to the benefits (AAHUs) than to

artificially lower the HSI. It would seem more appropriate to provide a more accurate measure

of the habitat quality (HSI) for the open water component and then adjust the benefits resulting

from the Study to that component than to do the opposite. This response is consistent with

responses previously provided to the ECO-PCX regarding certification of the WVA Models by

the US Fish and Wildlife Service (USFWS), other model users, and the ERDC reviewers

(McKay and Fischenich manuscript dated September 21, 2009); see comments furnished in a

document entitled Draft Model Certification Review Report for the Wetland Value Assessment

Models, dated July 8, 2009.

5. Comment #5: Off-site or surrounding human impacts and disturbances should be addressed

by the models.

Response: The LCA TBBSR Study Area is located in remote areas and human activities related

to land use are not key drivers for these natural communities. While human activities and land

use disturbances are not key factors in the remote Study Areas, land use activities that create

open water are often significant factors. Human factors that create open water are accounted for

in the model input for variables such as percent open water, percent open water at a given depth,

edge and interspersion, etc. In assessing Future With Project and Future Without Project

conditions for a given project, assumptions are made regarding human activities that create open

water and increase marsh loss. These assumptions are documented in the Study reports and/or

appendices. The primary purpose of the WVA model is to evaluate habitat suitability. Human

impacts are only accounted for if they potentially affect the habitat. The potential impacts of

human disturbances in the LCA TBBSR Study, construction of the cement-filled geotextile bag

revetments and the construction of the sunken-barge rip-rap filled breakwaters on the Caminada

Headland; as well as potential natural disturbances, such as tropical storms and subsidence were

considered in the development of the land loss rates and other assumptions utilized in preparing

the WVA models.

6. Comment #6: Sea level is an important phenomenon and relative sea level rise and climate

change should be included in the models.


3

Response: Sea level change and climate change are important factors. The LCA TBBSR Study

was evaluated with the WVA models before more recent guidance regarding consideration of sea

level change. The impacts of sea level change and climate change were taken into consideration

when the Study team is forecasting the input variables (e.g. percent open water, percent open

water at a given depth, edge and interspersion). These forecasts are made using the best

available engineering models and expert judgment. In addition, local subsidence rates, relative

sea level rise and shoreline erosion are considered when determining land loss rates used in the

models.

7. Comment #7: Validation of the models based on performance measures needs to be described

and documented.

Response: Two of the three levels of validation and testing outlined in the comments have been

conducted on the WVA models. Expert review was conducted by the model development team.

This model review effort was intended to meet the Expert Review validation level. Testing with

hypothetical (and real) data has been conducted since the models were developed and in use

beginning in early 1990s. Users have assessed the model structure, output and sensitivity of the

models and the models have been modified based on this information. These validation and

testing steps that have been conducted will be described in the model documentation.

8. Comment #8: The model documentation should clearly state the basis for the model

assumptions, the theoretical basis of the models and how the science is applied for these

ecosystems, and how the models were developed to eliminate the appearance of subjectivity.

Response: See response to Comment 2.

9. Comment #9: The methods for data collection are unclear and not well-documented, therefore

data quality is uncertain.

Response: We concur that additional documentation in the WVA Model guidance related to

variable measurement would be helpful. However, the LCA TBBSR team has considerable

experience in utilizing the WVA models. The specific items identified in this comment will be

evaluated and considered by an interagency team. The model documentation will be revised

accordingly. Revisions will recommend use of available tools and methods, but will not be

prescriptive, such that as better tools are developed they can be used. The quality of the input

data should also be evaluated as part of the Agency Technical Review process.

10. Comment #10: For some model variables, policy decisions appear to supersede what is

known about the ecology and hydrology of the relationships.

Response: We acknowledge the potential problems associated with Variables 1, 2, and 3 of the

WVA Marsh Models, especially when using a short period of analysis such as with the 20-year

period of analysis utilized in typical CWPPRA (Coastal Wetlands Planning, Protection and

Preservation Act) projects. Application of the WVA Models to compare stable marsh with

deteriorating marsh is likely problematic when using a short period of analysis as the short term

benefits of the deteriorating marsh are typically higher than solid marsh. However, for the LCA

TBBSR Study it is anticipated that these problems are not as significant when the period of

analysis is longer (50 years). Another important point is that the solid marsh provides some

storm attenuation functions not currently measured by the models. These are real benefits and


4

not solely policy. These benefits are typically appropriate to add discussion on the flood risk

benefits of marsh.

11. Comment #11: The spreadsheets for the models as created are likely to lead to errors in

maintenance and use.

Response: We concur that the WVA spreadsheets are potentially susceptible to these problems

especially for novice model users. Spreadsheet/model documentation and revision of

spreadsheets to allow the majority of calculations to be completed within the spreadsheet would

potentially reduce susceptibility of errors, especially for novice model users. However, the LCA

TBBSR habitat analysis was conducted by an interagency team each with over a decade or more

of experience in using and conducting the WVA analysis and this issue is not considered

significant for the LCA TBBSR Study.

12. Comment #12: Several inaccuracies were identified in the model spreadsheets that should be

corrected (spreadsheet issue).

Response: We concur with the reviewers that calculations should be modified to allow the

spreadsheet to make calculations. This would be especially useful for novice model users.

However, the LCA TBBSR habitat analysis was conducted by an interagency team each with

over a decade or more of experience in using and conducting the WVA analysis and this issue is

not considered significant for the LCA TBBSR Study.

13. Comment #13: The usability of the spreadsheets is limited because of the spreadsheets user

interface and user and maintainer documentation.

Response: We concur that improvements to the interface would improve model utility especially

for novice model users. However, the LCA TBBSR habitat analysis was conducted by an

interagency team each with over a decade or more of experience in using and conducting the

WVA analysis and this issue is not considered significant for the LCA TBBSR Study.

14. Comment #14: Data validation needs to be built into the spreadsheets.

Response: Concur that a spreadsheet specialist should build data validation into the spreadsheet.

However, the LCA TBBSR habitat analysis was conducted by an interagency team each with

over a decade or more of experience in using and conducting the WVA analysis and this issue is

not considered significant for the LCA TBBSR Study.

15. Comment #15: The WVA method should be expanded to handle risk and uncertainty in areas

exposed to episodic events.

Response: Risk and uncertainty are already incorporated into the WVA model inputs for the

LCA TBBSR Study. Currently risk and uncertainty are considered in the engineering model,

such as SBEACH, used to develop WVA model input for the LCA TBBSR Study. Other sources

of risk and uncertainty also considered in the WVA model include sea level change, subsidence,

and frequency of tropical storms. In addition, the Study reports will address how risk and

uncertainty were addressed.

16. Comment #16: The WVA method should be updated, taking into account new sources of GIS

data, LIDAR, and other new data sources, as well computer simulation and visualization tools.


5

Response: The WVA Procedural Manual references geospatial and other data sources as a guide,

but is not intended to be prescriptive or exhaustive. The WVA model used for the LCA TBBSR

Study included use of the most recent available imagery and land loss data available from the US

Geological Service as well as the most appropriate historic imagery that was used in determining

land loss and habitat conversion.

17. Comment #17: Development and documentation of a more precise approach to

measurement of some variables could be improved.

Response: see response to comment #9.

18. Comment #18: The use of the geometric mean may be more appropriate than the arithmetic

mean to derive some HSIs. Provide scientific basis for the decision to use one over the other.

Response: With regard to the LCA TBBSR Study, while applying geometric weighting as well

as other weighting schemes that accomplish the same aim may change the overall magnitude of

the output, it does not affect the relative ranking of alternatives. This response is consistent with

responses previously provided to the ECO-PCX regarding certification of the WVA Models by

ERDC reviewers (McKay and Fischenich manuscript dated September 21, 2009).

19. Comment #19: A performance measure should be stipulated to identify the measurable

community characteristics to which the HSIs are related.

Response: We concur that performance measures (such as species diversity) could be developed

for each WVA community model and that such information on the performance measures could

be added to the model documentation. With regard to the LCA TBBSR Study, because of long

standing standardizations of CWPPRA we feel this approach is appropriate and consistent until

further refined.

20. Comment #20: The geographic boundaries/domain of the models is unclear.

Response: The geographic boundary for the WVA model used in the LCA TBBSR Study is

clearly delineated in the WVA Project Information Sheet prepared for this particular Study as

well as the Study impact area described in the EIS. This issue is not considered significant for the

LCA TBBSR Study.

21. Comment #21: An explicit statement should be provided regarding the minimum area to

which the models can be applied.

Response: The geographic boundary for the WVA model used in the LCA TBBSR Study is

clearly delineated in the WVA Project Information Sheet prepared for this particular Study as

well as the Study impact area described in the EIS. This issue is not considered significant for

the LCA TBBSR Study.

22. Comment #22. Additional error checks should be incorporated into the model spreadsheets.

Response: We concur that more specific error messages/information be incorporated into model

error messages. However, the LCA TBBSR habitat analysis was conducted by an interagency

team each with over a decade or more of experience in using and conducting the WVA analysis

and this issue is not considered significant for the LCA TBBSR Study.



APPENDIX L

ENGINEERING INVESTIGATIONS

AND COST ESTIMATES



i

TERREBONNE BASIN BARRIER SHORELINE RESTORATION

FINAL FEASIBILITY REPORT

APPENDIX L - ENGINEERING INVESTIGATIONS AND COST ESTIMATES

TABLE OF CONTENTS

L1. GENERAL.......................................................................................................... 1-1

L1.1 INTRODUCTION ................................................................................................. 1-1

L1.2 EXISTING CONDITIONS...................................................................................... 1-4

L1.2.1 Isles Dernieres Reach......................................................................... 1-4

L1.2.2 Timbalier Reach................................................................................. 1-4

L1.3 PROBLEM IDENTIFICATION................................................................................ 1-5

L2. COASTAL PROCESSES.................................................................................. 2-1

L2.1 INTRODUCTION ................................................................................................. 2-1

L2.2. WINDS .............................................................................................................. 2-2

L2.3 WAVES ............................................................................................................. 2-4

L2.4 TIDES................................................................................................................ 2-9

L2.5 CURRENTS ........................................................................................................ 2-9

L2.6 STORMS .......................................................................................................... 2-10

L2.7 RELATIVE SEA-LEVEL CHANGE ...................................................................... 2-17

L2.8 DEPTH OF CLOSURE ........................................................................................ 2-21

L3. SURVEYING AND MAPPING........................................................................ 3-1

L3.1 HISTORICAL SURVEYS ...................................................................................... 3-1

L3.1.1 Land and Water Area Surveys ........................................................... 3-1

L3.1.2 Bathymetric Surveys.......................................................................... 3-1

L3.2 SHORELINE CHANGE ANALYSIS........................................................................ 3-3

L3.3 LAND LOSS RATE ANALYSIS ............................................................................ 3-4

L3.4 SEDIMENT BUDGET........................................................................................... 3-8

L3.4.1 Isles Dernieres.................................................................................... 3-9

L3.4.2 Timbalier Islands ............................................................................... 3-9

L3.5 AERIAL PHOTOGRAPHY .................................................................................... 3-9

L4. ENVIRONMENTAL ......................................................................................... 4-1

L4.1 ENVIRONMENTAL SETTING ............................................................................... 4-1

L4.1.1 Hydrology .......................................................................................... 4-1

L4.1.2 Habitat Types..................................................................................... 4-2

L4.1.3 Land Cover......................................................................................... 4-2

L4.1.4 Wildlife Resources............................................................................. 4-5

L4.2 HAZARDOUS, TOXIC AND RADIOACTIVE WASTE .............................................. 4-5

L4.3 GEOLOGIC SETTING .......................................................................................... 4-6

L4.3.1 Geomorphic and Physiographic Setting............................................. 4-6

L4.3.1.1 Deltaic Cycle............................................................................. 4-6

L4.3.1.2 Delta Advancement................................................................... 4-9

L4.3.1.3 Delta Abandonment .................................................................. 4-9

L4.3.2 Soils.................................................................................................. 4-11


ii

L5. GEOTECHNICAL INVESTIGATIONS......................................................... 5-1

L5.1 INTRODUCTION ................................................................................................. 5-1

L5.1.1 Introduction and sediment search effort ............................................ 5-1

L5.1.2 Available project documentation ....................................................... 5-1

L5.1.3 Offshore Borrow Areas...................................................................... 5-2

L5.1.3.1 Ship Shoal (including South Pelto Blocks)............................... 5-4

L5.1.3.2 Raccoon Island Borrow Area.................................................... 5-4

L5.1.3.3 Whiskey Island Back Barrier Marsh Borrow Areas ................. 5-4

L5.1.3.4 New Cut Dune and Marsh Borrow Area................................... 5-5

L5.1.3.5 Timbalier Island Borrow Areas ................................................ 5-5

L5.2 BORROW AREA CHARACTERISTICS AND SCREENING CRITERIA ........................ 5-5

L5.2.1 Location relative to depth of closure ................................................. 5-5

L5.2.2 Borrow area geotechnical and geophysical data, analyses, and

Interpretation...................................................................................... 5-6

L5.2.3 Borrow area volumes ......................................................................... 5-6

L5.2.4 Cultural resources/petroleum infrastructure clearance ...................... 5-6

L5.2.5 Technical difficulty............................................................................ 5-6

L5.2.6 Navigation features ............................................................................ 5-7

L5.2.7 Mining impacts .................................................................................. 5-7

L5.3 FIRST-LEVEL BORROW AREA SCREENING PROCESS AND RESULTS .................. 5-7

L5.4 FINAL BORROW AREA SCREENING PROCESS AND RESULTS............................ 5-12

L5.5 SCREENED RESTORATION BORROW AREAS .................................................... 5-16

L5.6 WHISKEY ISLAND RESTORATION BORROW AREA 3........................................ 5-16

L5.6.1 Description....................................................................................... 5-16

L5.6.2 Geophysical Analysis....................................................................... 5-16

L5.6.3 Geotechnical Analysis ..................................................................... 5-17

L5.6.4 Volume and Summary ..................................................................... 5-17

L5.7 NEW CUT BORROW AREA 4............................................................................ 5-20

L5.7.1 Description....................................................................................... 5-20

L5.7.2 Geophysical Analysis....................................................................... 5-20

L5.7.3 Geotechnical Analysis ..................................................................... 5-20

L5.7.4 Volume and Summary ..................................................................... 5-20

L5.8 RACCOON ISLAND RESTORATION BORROW AREA 5 ....................................... 5-23

L5.8.1 Description....................................................................................... 5-23

L5.8.2 Geophysical Analysis....................................................................... 5-23

L5.8.3 Geotechnical Analysis ..................................................................... 5-23

L5.8.4 Volume and Summary ..................................................................... 5-23

L5.9 SOUTH PELTO BORROW AREA 6 ..................................................................... 5-27

L5.9.1 Description....................................................................................... 5-27

L5.9.2 Geophysical Analysis....................................................................... 5-27

L5.9.3 Geotechnical Analysis ..................................................................... 5-27

L5.9.4 Volume and Summary ..................................................................... 5-28

L5.10 SHIP SHOAL BORROW AREA 7 ........................................................................ 5-31

L5.10.1 Description....................................................................................... 5-31

L5.10.2 Geophysical Analysis....................................................................... 5-31

L5.10.3 Geotechnical Analysis ..................................................................... 5-31

L5.10.4 Volume and Summary ..................................................................... 5-32

L5.11 SUMMARY....................................................................................................... 5-35

L5.12 BACK-BARRIER ANALYSES............................................................................. 5-35


iii

L6. RESTORATION DESIGN PLANS.................................................................. 6-1

L6.1 GOAL STATEMENT............................................................................................ 6-1

L6.2 BARRIER ISLAND GEOMORPHOLOGIC FORM AND ECOLOGIC FUNCTION........... 6-1

L6.3 PLAN FORMULATION SUMMARY....................................................................... 6-2

L6.3.1 Introduction.......................................................................................... 6-2

L6.3.2 Summary of Measures ......................................................................... 6-2

L6.3.3 First Level Screening........................................................................... 6-2

L6.3.4 Second Level Screening....................................................................... 6-4

L6.3.5 Third Level Screening ......................................................................... 6-4

L6.3.6 No Action Plan (Plan A)...................................................................... 6-5

L6.4 RESTORATION DESIGN STEPS ........................................................................... 6-5

L6.5 BARRIER ISLAND COMPONENTS........................................................................ 6-5

L6.5.1 Definition............................................................................................. 6-5

L6.5.2 Beach and Dune ................................................................................... 6-6

L6.5.3 Marsh ................................................................................................... 6-6

L6.6 DESIGN CRITERIA (PLAN B).............................................................................. 6-7

L6.6.1 Bathymetric/Topographic Data............................................................ 6-7

L6.6.2 Historic Erosion Rates ......................................................................... 6-7

L6.6.3 Relative Sea Level Change .................................................................. 6-7

L6.6.4 Fill Compaction ................................................................................... 6-7

L6.6.5 Existing CWPPRA Projects................................................................. 6-8

L6.6.6 Summary.............................................................................................. 6-8

L6.7 RESTORATION DESIGNS FOR VARIOUS DESIGN PERIODS (PLANS C, D, AND E) 6-9

L6.7.1 Design Definition......................................................................................... 6-9

L6.7.2 Design Components..................................................................................... 6-9

L6.7.2.1 Historic Erosion Rates ......................................................................... 6-9

L6.7.2.2 Design Storm Events ........................................................................... 6-9

L6.7.2.3 Historic Land Loss Rates................................................................... 6-10

L6.7.2.4 Relative Sea Level Change ................................................................ 6-10

L6.7.2.5 Existing CWPPRA Projects............................................................... 6-10

L6.8 HARD-STRUCTURAL MEASURE DESIGNS........................................................ 6-11

L6.8.1 Hard-structural Design Parameters ............................................................ 6-11

L6.8.1.1 Raccoon Island  Additional Breakwaters......................................... 6-11

L6.8.1.2 Raccoon Island  Terminal Groin...................................................... 6-11

L6.8.1.3 Whiskey Island  Breakwaters .......................................................... 6-11

L6.8.2 Operation & Maintenance Measures.......................................................... 6-12

L6.8.2.1 Breakwaters and Terminal Groin....................................................... 6-12

L6.9 PROTECTION OF EXISTING HABITATS ............................................................. 6-12

L6.10 HABITAT ACREAGES....................................................................................... 6-13

L6.11 NATIONAL ECOSYSTEM RESTORATION (NER) PLAN ...................................... 6-14

L6.12 FIRST COMPONENT OF CONSTRUCTION........................................................... 6-15

L7. CONSTRUCTION PROCEDURES AND ACCESS...................................... 7-1

L7.1 BEACH AND DUNE FILL .................................................................................... 7-1

L7.2 BACK-BARRIER MARSH FILL............................................................................ 7-1

L7.3 CONSTRUCTION ACCESS ................................................................................... 7-2

L8. ADAPTIVE MANAGEMENT PLAN (OPERATIONS AND

MAINTENANCE).............................................................................................. 8-1


iv

L9. COST ESTIMATES .......................................................................................... 9-1

L9.1 CONCEPTUAL COST ESTIMATE.......................................................................... 9-1

L9.1.1 Basis............................................................................................................. 9-1

L9.1.2 Assumptions................................................................................................. 9-3

L9.1.3 Contingencies............................................................................................... 9-4

L9.1.4 Refined Conceptual Cost Estimates............................................................. 9-5

L9.2 PRELIMINARY COST ESTIMATE......................................................................... 9-5

L9.2.1 Basis............................................................................................................. 9-5

L9.2.2 Assumptions................................................................................................. 9-8

L9.2.3 Contingencies............................................................................................... 9-8

L9.3 DETAILED COST ESTIMATE............................................................................... 9-8

L9.3.1 Basis............................................................................................................. 9-9

L9.3.2 Assumptions............................................................................................... 9-13

L9.3.3 MCACES ................................................................................................... 9-13

L9.3.4 Risk Analysis ............................................................................................. 9-17

L9.4 TOTAL PROJECT COST SUMMARY................................................................... 9-20

L9.4.1 Contingencies............................................................................................. 9-20

L9.4.2 Project Cost Estimate................................................................................. 9-24

L9.4.3 Project Schedule......................................................................................... 9-25

L9.4.4 Fully Funded Project Cost ......................................................................... 9-26

L10. RELOCATIONS.............................................................................................. 10-1

L11. SCHEDULE...................................................................................................... 11-1

L11.1 DESIGN SCHEDULE........................................................................................... 11-1

L11.2 CONSTRUCTION SCHEDULE.............................................................................. 11-1

L11.2.1 NER PLAN Initial Restoration Schedule ................................................... 11-1

L11.2.2 NER PLAN O&M and Renourishment Construction Schedule................. 11-9

L11.2.3 First Component of Construction Initial Restoration Schedule.............. 11-10

L11.2.4 First Component of Construction Renourishment Construction

Schedule.................................................................................................. 11-13

L11.3 ADAPTIVE MANAGEMENT AND MONITORING PLAN SCHEDULE..................... 11-13

L12. VALUE ENGINEERING REPORT.............................................................. 12-1

L12.1 INTRODUCTION ................................................................................................ 12-1

L12.2 VALUE ENGINEERING PROCESS ....................................................................... 12-1

L12.3 VALUE ENGINEERING ALTERNATIVE CONCEPTS.............................................. 12-2

L12.3.1 Alternative Concept Descriptions - Terrebonne Basin Barrier

Shoreline Restoration............................................................................... 12-3

L12.3.2 Alternative Concept Descriptions - General/Plan Formulation............. 12-15

L12.4 PROJECT ANALYSIS........................................................................................ 12-22

L12.5 IDEA EVALUATION......................................................................................... 12-24

L12.5.1 Introduction ........................................................................................... 12-24

L12.5.2 Performance Attributes.......................................................................... 12-24

L12.5.3 Evaluation Process................................................................................. 12-24

L12.5.4 Idea Evaluation...................................................................................... 12-24

L12.6 VALUE ENGINEERING STUDY RESULTS.......................................................... 12-27

L13. REFERENCES................................................................................................. 13-1


v

LIST OF FIGURES

L1-1. Study Area Location Map.................................................................................... 1-2

L1-2. Terrebonne Basin Barrier Islands Study Area ..................................................... 1-3

L2-1. WIS Station Location Map .................................................................................. 2-1

L2-2. Wind Rose at WIS Station 128 ............................................................................ 2-2

L2-3. Wind Rose at WIS Station 125 ............................................................................ 2-3

L2-4. Wave Rose at WIS Station 128............................................................................ 2-4

L2-5. Wave Rose at WIS Station 125............................................................................ 2-6

L2-6. Extremal Wave Height Distribution at WIS Station 128..................................... 2-7

L2-7. Extremal Wave Height Distribution at WIS Station 125..................................... 2-8

L2-8. Tracks of Recent Hurricanes.............................................................................. 2-11

L2-9. Water Level (Grand Isle) and Wave Data (WIS-128) During Katrina

and Rita .............................................................................................................. 2-12

L2-10. Water Level (Grand Isle) and Wave Data (WIS-128) During Gustav

and Ike................................................................................................................ 2-12

L2-11. Water Level (Grand Isle) and Wave Data (WIS-125) During Katrina

and Rita .............................................................................................................. 2-13

L2-12. Water Level (Grand Isle) and Wave Data (WIS-125) During Gustav

and Ike................................................................................................................ 2-13

L2-13. Wind Speed During Katrina and Rita at WIS-128............................................. 2-14

L2-14. Wind Speed During Gustav and Ike at WIS-128............................................... 2-15

L2-15. Wind Speed During Katrina and Rita at WIS-125............................................. 2-15

L2-16. Wind Speed During Gustav and Ike at WIS-125............................................... 2-16

L2-17. Sea Level Rise at Grand Isle.............................................................................. 2-17

L2-18. 18-step Flowchart to Account for Changes in MSL (USACE, 2009) ............... 2-18

L2-19. Estimated Relative Sea Level Rise since 2006.................................................. 2-20

L3-1. 2006 BICM Survey.............................................................................................. 3-3

L3-2. Raccoon Island USGS Land Loss Trend Analysis from 1985 to 2006 ............... 3-4

L3-3. Whiskey Island USGS Land Loss Trend Analysis from 1985 to 2006 ............... 3-5

L3-4. Trinity/East Island USGS Land Loss Trend Analysis from 1985 to 2006 .......... 3-5

L3-5. Timbalier Island USGS Land Loss Trend Analysis from 1985 to 2006.............. 3-6

L3-6. East Timbalier Island USGS Land Loss Trend Analysis from 1985 to 2006...... 3-6

L3-7. Longshore Sediment Transport Estimate in Coastal Louisiana........................... 3-8

L4-1. Land Cover Classifications.................................................................................. 4-4

L4-2. Mississippi River Deltaic Plain............................................................................ 4-8

L4-3. Three-Stage Geomorphic Model........................................................................ 4-10

L5-1. Coastal Louisiana Borrow Areas, Courtesy Khalil et al., 2010........................... 5-3

L5-2. First-level Borrow Area Screening Map............................................................ 5-11

L5-3. Final Borrow Area Screening Map.................................................................... 5-15

L5-4. Whiskey Island Restoration Borrow Area 3 ...................................................... 5-18

L5-5. Whiskey Island Restoration Borrow Area 3 Typical Section............................ 5-19

L5-6. New Cut Borrow Area 4 Plan View .................................................................. 5-21

L5-7. New Cut Borrow Area 4 Typical Section.......................................................... 5-22

L5-8. Raccoon Island Restoration Borrow Area 5 Plan View..................................... 5-25

L5-9. Raccoon Island Restoration Borrow Area 5 Typical Section ............................ 5-26

L5-10. South Pelto Borrow Area 6 Plan View .............................................................. 5-29

L5-11. South Pelto Borrow Area 6 Typical Section...................................................... 5-30

L5-12. Ship Shoal Borrow Area 7 Plan View ............................................................... 5-33

L5-13. Ship Shoal Borrow Area 7 Typical Section....................................................... 5-34

L12-1. Inverted Breakwater Concept ............................................................................ 12-3

L12-2. Geotube Incorporation in Beach Design Concept ........................................... 12-11

L12-3. Approximate Areas of High Concentrations of Oil & Gas Wells ................... 12-19

L12-4. Oil & Gas Infrastructure .................................................................................. 12-20


vi

LIST OF TABLES

L2-1. Directional Wind Statistics at WIS-128............................................................... 2-2

L2-2. Directional Wind Statistics at WIS-125............................................................... 2-3

L2-3. Directional Wave Statistics at WIS-128 .............................................................. 2-5

L2-4. Seasonal Wave Statistics at WIS-128.................................................................. 2-5

L2-5. Directional Wave Statistics at WIS-125 .............................................................. 2-6

L2-6. Seasonal Wave Statistics at WIS-125.................................................................. 2-7

L2-7. Extremal Wave Parameters vs. Return Period for Station 128............................ 2-8

L2-8. Extremal Wave Parameters vs. Return Period for Station 125............................ 2-9

L2-9. Grand Isle Tide Datum......................................................................................... 2-9

L2-10. Historical Hurricanes (1985-2008) .................................................................... 2-10

L2-11. Estimated Design Relative to Sea Level Changes ............................................. 2-19

L2-12. Sea-Level Rise Induced Shoreline Recession Between 2006 and 2062............ 2-21

L3-1. Summary of Land and Water Area Surveys in Coastal Louisiana ...................... 3-1

L3-2. Summary of Bathymetric and Topographic Surveys in Terrebonne Basin

Area...................................................................................................................... 3-2

L3-3. Long-Term Shoreline and Short-Term Marsh Land Loss Change Rates ............ 3-7

L3-4. Year of Disappearance Based on Shoreline & Marsh Change Rates and

Intermediate SLR Trend ...................................................................................... 3-7

L3-5. Longshore Sediment Transport Rates in Coastal Louisiana (after Georgiou et

al., 2005) .............................................................................................................. 3-9

L5-1. Initial Level Borrow Area Screening Table......................................................... 5-8

L5-2. Final Borrow Area Screening Table .................................................................. 5-13

L6-1. Initial Screening Results by Management Measure............................................. 6-3

L6-2. Second Level Screening Results by Island .......................................................... 6-4

L6-3. Final Level Screening Results by Island.............................................................. 6-5

L6-4. Marsh Thickness and Compaction Values........................................................... 6-8

L6-5. Summary of TY0 Minimized Template Dimensions (Plan B) ............................ 6-8

L6-6. Short-Term Marsh Loss Rates ........................................................................... 6-10

L6-7. Summary of Created Habitat Acres ................................................................... 6-13

L6-8. Renourishment Sequencing and Plans....................... 6-15

L9-1. NER Plan Borrow Areas and Cut Volumes Summary ...................................... 9-10

L9-2. First Component of Construction Borrow Areas and Cut Volumes Summary . 9-11

L9-3. NER Plan and First Component of Construction Required Fill Quantities

Breakdown ......................................................................................................... 9-12

L9-4. Project Cost Estimate w/Contingency Summary (NER Plan Initial

Restoration, Contract No. 1) .............................................................................. 9-21

L9-5. Project Schedule w/Contingency Summary (NER Plan Initial Restoration,

Contract No. 1)................................................................................................... 9-21

L9-6. Project Cost Estimate w/Contingency Summary (NER Plan Initial

Restoration, Contract No. 2) .............................................................................. 9-22

L9-7. Project Schedule w/Contingency Summary (NER Plan Initial Restoration,

Contract No. 2)................................................................................................... 9-22

L9-8. Project Cost Estimate w/Contingency Summary (First Component of

Construction Initial Restoration)........................................................................ 9-23

L9-9. Project Schedule w/Contingency Summary (First Component of

Construction Initial Restoration)........................................................................ 9-23

L9-10. NER Plan Initial Restoration Project Cost Summary - Program Year (2012)... 9-24

L9-11. First Component of Construction Initial Restoration Project Cost Summary -

Program Year (2012) ......................................................................................... 9-24

L9-12. Fully Funded Cost Summary for NER Plan Initial Restoration ........................ 9-26


vii

L9-13. Fully Funded Cost Summary for First Component of Construction Initial

Restoration ......................................................................................................... 9-27

L9-14. Fully Funded Cost Summary for TY10 Terminal Groin O&M......................... 9-27

L9-15. Fully Funded Cost Summary for Whiskey Is. TY20 Renourishment................ 9-28

L9-16. Fully Funded Cost Summary for Trinity Is. TY25 Renourishment................... 9-28

L9-17. Fully Funded Cost Summary for Raccoon Is. and Timbalier Is. TY30

Renourishment ................................................................................................... 9-28

L9-18. Fully Funded Cost Summary for Whiskey Is. TY40 Renourishment................ 9-29

L12-1. Summary of Value Engineering Alternative Concepts...................................... 12-2

L12-2. Idea Evaluation Summary................................................................................ 12-25

ANNEX L-1 BORROW AREA DESIGN PLANS

Whiskey Island Restoration Borrow Area 3 Design Plans

New Cut Borrow Area 4 Design Plans

Raccoon Island Restoration Borrow Area 5 Design Plans

South Pelto Borrow Area 6 Design Plans

Ship Shoal Borrow Area 7 Design Plans

Included on supplemental compact disk:

Whiskey Island Restoration Borrow Area 3 Vibracore Logs (2007)

New Cut Borrow Area 4 Vibracore Logs (2005)

Raccoon Island Restoration Borrow Area 5 Vibracore Logs (2006)

South Pelto Borrow Area 6 Vibracore Logs (2003)

South Pelto Borrow Area 6 Vibracore Logs (2005)

Ship Shoal Borrow Area 7 Vibracore Logs (2003)

Ship Shoal Borrow Area 7 Vibracore Logs (2005)

ANNEX L-2 ISLAND DESIGN PLANS

Raccoon Island Plans B, C, D, and E

Whiskey Island Plans B, C, D, and E

Trinity Island Plans B, C, D, and E

East Island Plans B, C, D, and E

Wine Island Plans B, C, D, and E

Timbalier Island Plans B, C, D, and E

East Timbalier Island Plans B, C, D, and E

Raccoon Island Breakwaters and Terminal Groin

Whiskey Island Breakwaters

ANNEX L-3 SUPPLEMENTAL MODELING REPORTS

GENESIS Modeling Report

SBEACH Modeling Report

ANNEX L-4 MCACES COST ESTIMATES

MII Cost Estimate Reports for the NER Plan and First Component of

Construction Initial Restorations

ANNEX L-5 RISK ANALYSES REPORTS

Risk Analysis Reports for the NER Plan and First Component of Construction

Initial Restorations

ANNEX L-6 TOTAL PROJECT COST SUMMARIES

Total Project Cost Summaries for the NER Plan and First Component of

Construction Initial Restorations


1-1

L1. GENERAL

L1.1 INTRODUCTION

This document serves as the Engineering Appendix Report for the Louisiana Coastal

Area, Terrebonne Basin Barrier Shoreline Restoration (LCA TBBSR) Study.

The overarching problem affecting the Terrebonne Basin barrier shoreline is the lack of

sustainability of the ecosystem, primarily due to coastal land loss. Natural processes and

human actions have resulted in extensive habitat loss and ecosystem degradation, and

therefore threaten the long-term viability of the barrier islands (USACE, 2004a).

The LCA TBBSR Study, located in LCA Subprovince 3, provides for the restoration of

the Timbalier and Isles Dernieres Barrier Island reaches located in Terrebonne and

Lafourche Parishes, Louisiana. The Study Area (Figure L1-1) is located in the 3rd

Congressional District. The barrier islands being considered for restoration are presented

in Figure L1-2.


Figure L1-1. Study Area Location Map.


Figure L1-2. Terrebonne Basin Barrier Islands Study Area.


1-4

L1.2 EXISTING CONDITIONS

The Terrebonne Basin, similar to the rest of coastal Louisiana, including its wetlands, lakes, bays,

and barrier shorelines, were produced by the deltaic processes of the Mississippi River in the east

and Gulf and riverine processes in the west. The Terrebonne Basin barrier islands provide unique

habitats that are crucial to the viability of migratory birds, commercial and recreational fisheries,

and a great variety of aquatic species. In addition, the barrier islands reduce the impact of storminduced flooding and surges on infrastructure in the coastal region, including highways, oil and gas

production facilities, pipelines, and navigation features, such as ports and channels (USACE,

2008).

L1.2.1 Isles Dernieres Reach

The Isles Dernieres reach represents a barrier island arc approximately 22 miles long in the

southern reaches of Terrebonne Parish and extends from Caillou Bay east to Cat Island Pass.

Raccoon, Whiskey, Trinity, East, and Wine, the primary islands that comprise the Isles Dernieres

reach, are backed by Bay Blanc, Bay Round, Caillou Bay and Terrebonne Bay, and bordered by

the Gulf of Mexico (GOM) on the seaward side. The remnant of Wine Island is located in Wine

Island Pass, about midway between East and Timbalier Islands. The islands of the Isles Dernieres

reach range from approximately 0.1 to 0.85 miles wide and are typically composed of a thin sand

cap over a thick mud platform. Elevations are generally low and the islands are frequently

overwashed (USACE, 2004c).

For more than a century, the Isles Dernieres have experienced significant and persistent

degradation and fragmentation. The average historic (18872002) rate of shoreline change for the

Isles Dernieres was -34.7 ft/yr with a range of -56.0/-17.0 ft/yr. The average short-term (1988

2002) rate of shoreline change was -61.9 ft/yr with a range of -60.5/-38.6 ft/yr (USACE, 2004c).

For more than 150 years, the Isles Dernieres has been an important commercial and recreational

resource for Louisiana and the nation. The primary commercial activities in the area, oil and gas

mineral extraction and fisheries harvesting, are interwoven inshore and offshore of the islands. As

well, the islands have historically played an important role in coastal Louisiana recreation. The

Isles Dernieres contained the first major coastal resort in Louisiana (later washed away by the

great hurricane of 1856), and continues to provide premier hunting and fishing recreation for both

State residents and non-residents alike (USACE, 2004c).

L1.2.2 Timbalier Reach

The Timbalier reach is comprised of Timbalier Island and East Timbalier Island. Timbalier and

East Timbalier Islands are on the western edge of the Lafourche barrier shoreline and are located

about 60 miles southwest of New Orleans, Louisiana. This barrier island shoreline is

approximately 20 miles long and backed by Terrebonne and Timbalier Bay to the north and

delimited by Raccoon Pass to the east and Cat Island Pass to the west. The islands range from 0.1

to 0.6 miles wide, with low elevations. Though onshore and offshore oil and gas development and

production facilities are supported by both Timbalier and East Timbalier Islands, those facilities

are prevalent on and around the East Timbalier but are few and scattered along Timbalier Island.

Oil and gas canals are present on both islands (USACE, 2004c).


1-5

According to USACE (2004c), the average historic rates of shoreline change for the Timbalier

Islands was -36.1 ft/yr with a range of -61.2/-4.1 ft/yr between 1887 and 2002. The average shortterm rate of shoreline change was -76.4 ft/yr with a range of -179.4/-13.4 ft/yr between 1988 and

2002.

L1.3 PROBLEM IDENTIFICATION

This Project was designed to address general barrier island restoration problems and opportunities

in the Study Area. In 1990, passage of the Coastal Wetlands Planning, Protection, and Restoration

Act (CWPPRA, PL-101-646, Title III) provided authorization and funding for the Louisiana

Coastal Wetlands Conservation and Restoration Task Force to begin actions to curtail wetland

losses.

Numerous regional and site-specific investigations of erosion and shoreline loss have been

conducted along the Terrebonne Basin barrier island reaches. Five of the most comprehensive

studies conducted are listed below:

Coast 2050 Plan: Toward a Sustainable Coastal Louisiana;

Louisiana Coastal Area (LCA), Louisiana Ecosystem Restoration Study (2004 LCA Plan);

Louisiana Coastal Protection and Restoration (LACPR) Technical Plan;

Ecosystem Restoration and Hurricane Protection in Louisiana (CPRA); and

T. Baker Smith Barrier Shoreline Feasibility Study.

In the 2004 LCA Plan, the Terrebonne Basin barrier shoreline was considered near-critical due to

the greatly degraded state of this shoreline and its key role in defining, protecting, and preserving

larger inland wetland areas and bay systems. If these fragile areas were not addressed quickly,

restoration would be far more difficult and costly. As a result, the 2004 LCA Plan identified the

LCA TBBSR as one of 10 critical projects that could be implemented within the near-term, based

on proven restoration techniques.


2-1

L2. COASTAL PROCESSES

L2.1 INTRODUCTION

The major processes operating to shape the Terrebonne Basin barrier islands include

waves, storms, tides, relative sea level rise, tidal inlets and tidal prism, currents, and

sediment transport.

The Wave Information Studies (WIS) database was utilized to analyze wind and wave

conditions specific to the Terrebonne Basin barrier shoreline. WIS project (Hubertz,

1992) produces a high-quality online database of hindcast, nearshore wave conditions

covering U.S. coastlines (http://chl.erdc.usace.army.mil/). The data cover a 20-year

period from January 1, 1980 through December 31, 1999. The time interval of the data is

one hour. Figure L2-1 presents a location map of WIS stations off the coast of Louisiana.

Figure L2-1: WIS Station Location Map

WIS data used in the analysis were obtained at Station 128 (WIS-128) located in 66 ft

water depth at (LAT=28.83N, LON=90.33W), approximately 17 miles southeast of

Timbalier Island, and Station 125 (WIS-125) located in 59 ft water depth at

(LAT=28.58N, LON=90.75W), approximately 32 miles south of East Island.


2-2

L2.2 WINDS

Figures L2-2 and L2-3 and Tables L2-1 and L2-2 present wind roses and directional wind

statistics based on the 20-year period at WIS-128 and WIS-125, respectively.

Figure L2-2: Wind Rose at WIS Station 128

Table L2-1. Directional Wind Statistics at WIS-128

Angle Band Average Wind

Speed (ft/s) % Occurrence

348.75 - 11.24 25.1 7.3

11.25 - 33.74 24.8 6.8

33.75 - 56.24 22.6 7.3

56.25 - 78.74 21.6 6.3

78.75 - 101.24 20.4 8.4

101.25 - 123.74 20.1 7.7

123.75 - 146.24 20.4 9.3

146.25 - 168.74 21.4 8.5

168.75 - 191.24 20.2 7.6

191.25 - 213.74 18.6 4.5

213.75 - 236.24 17.5 4.3

236.25 - 258.74 16.7 3.4

258.75 - 281.24 17.2 4.2

281.25 - 303.74 18.6 3.9

303.75 - 326.24 21.7 5.5

326.25 - 348.74 23.3 4.9


2-3

Figure L2-3: Wind Rose at WIS Station 125

Table L2-2. Directional Wind Statistics at WIS-125

Angle Band Average Wind

Speed (ft/s) % Occurrence

348.75 - 11.24 25.5 7.2

11.25 - 33.74 24.8 6.7

33.75 - 56.24 22.4 7.5

56.25 - 78.74 21.6 6.3

78.75 - 101.24 20.4 8.6

101.25 - 123.74 20.2 7.9

123.75 - 146.24 20.7 9.9

146.25 - 168.74 21.7 8.9

168.75 - 191.24 20.5 7.7

191.25 - 213.74 18.9 4.5

213.75 - 236.24 17.2 4.4

236.25 - 258.74 16.4 3.3

258.75 - 281.24 16.9 3.8

281.25 - 303.74 18.8 3.5

303.75 - 326.24 22.4 5.2

326.25 - 348.74 23.8 4.7


2-4

L2.3 WAVES

The wave climate along the Louisiana coast is a product of seasonal wind patterns and

the passage of tropical and extra-tropical storms. Wave data statistics from 1980 to 1999

were also generated using WIS data at Stations 128 and 125. Figure L2-4 presents a wave

rose at WIS-128 based on the 20-year period. Directional and seasonal wave statistics for

WIS-128 are presented in Tables L2-2 and L2-3, respectively. The mean significant wave

height, period and dominant wave direction for all the waves were approximately 3.4 ft,

4.5 seconds, and 112.5 degrees, respectively.

0.0 - 1.0

1.0 - 3.0

3.0 - 5.0

5.0 - 10.0

10.0 - 15.0

Width Legend

90

60

30

0

330

300

270

240

210

180

150

120 0

481216

Percent Occurrence Wave Direction (deg)

vs.

Wave Height (ft)

Figure L2-4: Wave Rose at WIS-128


2-5

Table L2-3. Directional Wave Statistics at WIS-128

Angle Band

(deg)

Avg. Wave

Height (ft) % Occurrence Avg. Period(sec)

348.75 - 11.24 3.1 2.9 3.8

11.25 - 33.74 3.1 3.6 3.8

33.75 - 56.24 3.7 5.5 4.4

56.25 - 78.74 3.7 6.9 4.5

78.75 - 101.24 3.4 9.9 4.6

101.25 - 123.74 3.1 15.6 4.5

123.75 - 146.24 3.3 14.8 4.7

146.25 - 168.74 3.9 13.0 5.0

168.75 - 191.24 3.8 6.9 4.9

191.25 - 213.74 3.3 4.4 4.5

213.75 - 236.24 2.6 3.4 4.1

236.25 - 258.74 2.6 3.1 4.1

258.75 - 281.24 3.0 2.8 4.2

281.25 - 303.74 3.5 2.8 4.2

303.75 - 326.24 3.4 2.4 4.0

326.25 - 348.74 3.1 2.0 3.8

Table L2-4. Seasonal Wave Statistics at WIS-128

Wave

Month Height (ft)

Avg. Max

Period*

(sec)

Direction*

(deg)

Jan. 4.0 15.4 11 163

Feb. 4.1 15.4 10 90

March 4.1 14.1 11 154

April 3.9 12.8 9 280

May 3.1 10.8 10 167

June 2.7 7.9 7 209

July 2.2 11.2 8 161

Aug. 2.1 21.7 11 111

Sept. 3.0 17.4 12 102

Oct. 3.6 29.2 14 132

Nov. 4.0 13.8 14 118

Dec. 4.0 13.1 9 281

Overall 3.4 29.2 14 132

*

period and direction associated with MAX wave height

Figure L2-5 presents a wave rose at WIS-125 and Tables L2-4 and L2-5 present

directional and seasonal wave statistics for WIS-125, respectively. The mean significant

wave height, period and dominant wave direction for all the waves were approximately

3.6 ft, 4.7 seconds, and 112.5 degrees, respectively.


2-6

0.0 - 1.0

1.0 - 3.0

3.0 - 4.0

4.0 - 10.0

10.0 - 15.0

Width Legend

90

60

30

0

330

300

270

240

210

180

150

120 0

481115

Percent Occurrence Wave Direction (deg)

vs.

Wave Height (ft)

Figure L2-5: Wave Rose at WIS-125

Table L2-5. Directional Wave Statistics at WIS-125

Angle Band

(deg)

Avg. Wave

Height (ft) % Occurrence Avg. Period (sec)

348.75 - 11.24 4.2 3.8 4.6

11.25 - 33.74 4.0 4.2 4.5

33.75 - 56.24 4.0 5.5 4.6

56.25 - 78.74 3.7 6.7 4.5

78.75 - 101.24 3.3 9.0 4.5

101.25 - 123.74 3.0 14.8 4.5

123.75 - 146.24 3.3 15.1 4.6

146.25 - 168.74 4.0 13.2 5.1

168.75 - 191.24 4.1 7.2 5.0

191.25 - 213.74 3.7 4.2 4.7

213.75 - 236.24 2.9 2.9 4.3

236.25 - 258.74 2.8 2.7 4.2

258.75 - 281.24 3.1 2.4 4.4

281.25 - 303.74 4.1 2.2 4.8

303.75 - 326.24 5.0 3.0 5.2

326.25 - 348.74 4.4 3.2 4.8


2-7

Table L2-6. Seasonal Wave Statistics at WIS-125

Wave

Month Height (ft)

Avg. Max

Period*

(sec)

Direction*

(deg)

Jan. 4.4 17.1 12 177

Feb. 4.5 15.4 11 86

March 4.5 15.1 11 162

April 4.1 12.5 8 283

May 3.2 11.5 8 174

June 2.8 9.5 9 139

July 2.2 13.1 10 138

Aug. 2.2 21.7 11 148

Sept. 3.1 17.7 12 154

Oct. 3.9 26.2 13 129

Nov. 4.4 16.4 14 130

Dec. 4.4 13.1 11 157

Overall 3.6 26.2 13 129

*

period and direction associated with MAX wave height

Figures L2-6 and L2-7 present extremal wave height distributions at WIS-128 and WIS125, respectively, based on which wave parameters associated with various return periods

were determined. These parameters are presented in Tables L2-7 and L2-8.

Figure L2-6: Extremal Wave Height Distribution at WIS Station 128


2-8

Figure L2-7: Extremal Wave Height Distribution at WIS Station 125

Table L2-7. Extremal Wave Parameters vs. Return Period for Station 128

Return Period

(years)

Wave

Height (ft)

Wave Period

(sec) Probability* Probability**

1 11.1 8.5 1.0 1.000

2 12.9 9.1 0.5 0.750

5 16.6 10.3 0.2 0.672

10 19.9 11.3 0.1 0.651

20 23.6 12.3 0.05 0.641

50 29.1 13.7 0.02 0.636

100 31.4 14.2 0.01 0.634

* indicates the probability of the event occurring in any given year

(e.g., the probability of a 20-year storm occurring in 2009 is 0.05 or 5% chance)

** indicated the probability of the event occurring during the corresponding return period

(e.g., the probability of a 10-year storm occurring during 2009-2018 is 0.651 or 65.1%

chance)


2-9

Table L2-8. Extremal Wave Parameters vs. Return Period for Station 125

Return Period

(years)

Wave

Height (ft)

Wave Period

(sec) Probability* Probability**

1 11.8 8.7 1.0 1.000

2 13.3 9.2 0.5 0.750

5 16.4 10.3 0.2 0.672

10 19.3 11.2 0.1 0.651

20 22.3 12.0 0.05 0.641

50 27.0 13.2 0.02 0.636

100 28.9 13.7 0.01 0.634

* indicates the probability of the event occurring in any given year

(e.g., the probability of a 20-year storm occurring in 2009 is 0.05 or 5% chance)

** indicated the probability of the event occurring during the corresponding return period

(e.g., the probability of a 10-year storm occurring during 2009-2018 is 0.651 or 65.1%

chance)

L2.4 TIDES

In the delta region including Raccoon Pass (west), Grand Isle (central), and the northern

Chandeleur Islands (east) tides are strongly diurnal. At Raccoon Pass, the tidal range

varies from a low of 0.5 ft during equatorial tidal conditions to a high of 3.2 ft during

tropic tides (USACE, 2004c).

The tidal datum at Grand Isle is presented in Table L2-9. The tidal datum is based on a

five year record from January 1997 through December 2001. The tidal epoch is 1983 to

2001 (NOAA).

Table L2-9. Grand Isle Tidal Datum

Description NAVD 88 (ft)

Mean Higher High Water (MHHW) 1.604

Mean High Water (MHW) 1.598

Mean Sea Level (MSL) 1.083

Mean Tide Level (MTL) 1.076

Mean Low Water (MLW) 0.554

Mean Lower Low Water (MLLW) 0.545

North American Vertical Datum of 1988 (NAVD 88) 0.000

L2.5 CURRENTS

Tidal prism dynamics and the pattern of tidal exchange dictate the occurrence and

geometry of tidal inlets along the various barrier island reaches. Tidal inlets along the

Timbalier Islands have highly variable geometries due to the segmented nature of the

barrier system. Much of the tidal exchange between the back-barriers of Caillou Bay,

Terrebonne Bay and Timbalier Bay and that of the Gulf of Mexico occurs through broad

shallow channels where the transgressive barriers have undergone extensive erosion.


2-10

However, there are several relatively deep passes (20 to 33 ft deep) that are maintained

by strong tidal currents on the order of 3.3 ft/s (USACE, 2004b).

L2.6 STORMS

The Gulf Coast region is affected by tropical and extra-tropical storms. Since 1893, over

130 tropical storms and hurricanes have struck or indirectly impacted Louisianas

coastline. On average, a tropical storm or hurricane affects Louisiana every 1.2 years.

During the past 100 years, over 50 hurricanes and tropical storms have made landfall

along the Louisiana coast with the highest incidence occurring in September (USACE,

2004a). Table L2-10 presents hurricanes that impacted the Terrebonne Basin from 1985

to 2008. Storm selection was based primarily on landfall location, but also on wave

height and water level elevations associated with the storm. Landfall locations were

obtained from NOAA Coastal Services Historical Hurricane storm track data

(http://maps.csc.noaa.gov/hurricanes/).

Table L2-10. Historical Hurricanes (1985-2008)

Storm

Name Year* Month* Day* Wind Speed*(knots) Category*

Danny 1985 8 15 80 H1

Elena 1985 9 2 100 H3

Juan 1985 10 29 70 H1

Bonnie 1986 6 26 75 H1

Andrew 1992 8 26 120 H4

Opal 1995 10 4 110 H3

Danny 1997 7 18 65 H1

Earl 1998 9 3 80 H1

Georges 1998 9 28 90 H2

Isidore 2002 9 26 55 TS

Lili 2002 10 3 80 H1

Ivan 2004 9 16 105 H3

Katrina 2005 8 29 125 H4

Rita 2005 9 24 100 H3

Gustav 2008 9 1 95 H2

Ike 2008 9 13 95 H2

* at landfall


2-11

Figure L2-8 presents tracks of four most recent storms including Hurricanes Katrina

(2005), Rita (2005), Gustav (2008), and Ike (2008). Hurricane Gustav made landfall

along the Terrebonne Basin barrier shoreline as a Category 2 hurricane. According to the

Grand Isle water level records, the highest observed water level in stations history

occurred during Katrina when it was measured at approximately 6.0 ft NAVD 88.

Figure L2-8: Tracks of Recent Hurricanes

Water level, wave and wind data for the four hurricanes were assembled. Water level data

were obtained from verified historical records at NOAA/NOS CO-OPS Station 8761724

located at the Coast Guard Station on Grand Isle. Wave and wind data were obtained

from the NOAA/NWS/NCEP operational ocean wave predictions based on the output

from the WAVEWATCH III model (http://polar.ncep.noaa.gov/waves/index2.shtml).

The wave and wind data were obtained near the WIS-128 and WIS-125 locations. Figures

L2-9 and L2-10 present water level and wave data near WIS-128 during Hurricanes

Katrina and Rita, and Gustav and Ike, respectively. Similarly, Figures L2-11 and L2-12

present the data near WIS-125.


2-12

Figure L2-9: Water Level (Grand Isle) and Wave Data (WIS-128) During Katrina and Rita

Figure L2-10: Water Level (Grand Isle) and Wave Data (WIS-128) During Gustav and Ike

Day (2005)

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

25

30

35

40

45

50

0

2

4

6

8

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27 Sep. 6 Sep. 1 Sep. 26

Hurricanes Katrina and Rita (2005)

at WIS-128

no water level data

Katrina

Rita

Sep. 11 Sep. 16 Sep. 21

Day (2008)

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

25

30

35

40

0

2

4

6

8

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27 Sep. 6 Sep. 1 Sep. 11

Hurricanes Gustav and Ike (2008)

at WIS-128

no water level data

Gustav

Ike


2-13

Figure L2-11: Water Level (Grand Isle) and Wave Data (WIS-125) During Katrina and Rita

Figure L2-12: Water Level (Grand Isle) and Wave Data (WIS-125) During Gustav and Ike

Day (2005)

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

25

30

35

40

45

50

0

2

4

6

8

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27 Sep. 6 Sep. 1 Sep. 26

Hurricanes Katrina and Rita (2005)

at WIS-125

no water level data

Katrina

Rita

Sep. 11 Sep. 16 Sep. 21

Day (2008)

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

25

30

35

40

0

2

4

6

8

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27 Sep. 6 Sep. 1 Sep. 11

Hurricanes Gustav and Ike (2008)

at WIS-125

no water level data

Gustav

Ike


2-14

The largest wave heights during Katrina and Rita at WIS-128 were approximately 43.4 ft

and 35.7 ft, respectively. The largest wave heights during Katrina and Rita at WIS-125

were approximately 46.3 ft and 31.8 ft, respectively. The maximum water levels that

occurred at the Grand Isle Station were 6.0 ft NAVD 88 and 5.0 ft NAVD 88,

respectively.

The largest wave heights during Gustav and Ike at WIS-128 were approximately 20.1 ft

and 30.0 ft, respectively. The largest wave heights during Gustav and Ike at WIS-125

were approximately 18.3 ft and 31.2 ft, respectively. The maximum water levels that

occurred at the Grand Isle Station were 5.8 ft NAVD 88 and 5.7 ft NAVD 88,

respectively.

Figures L2-13 through L2-16 present wind speed during Katrina and Rita, and Gustav

and Ike, at WIS-128 and WIS-125. The maximum wind speeds at WIS-128 during

Katrina, Rita, Gustav, and Ike were approximately 60 mph, 68 mph, 45 mph, and 53 mph,

respectively. The maximum wind speeds at WIS-125 during Katrina, Rita, Gustav, and

Ike were approximately 72 mph, 62 mph, 45 mph, and 59 mph, respectively.

Figure L2-13: Wind Speed During Katrina and Rita at WIS-128

Day (2005)

Wind Speed (mph)

0

10

20

30

40

50

60

70

80

Wind Speed

Katrina

Rita

Hurricanes Katrina and Rita (2005)

at WIS-128

Aug. 27 Sep. 1 Sep. 6 Sep. 11 Sep. 16 Sep. 21 Sep. 26


2-15

Figure L2-14: Wind Speed During Gustav and Ike at WIS-128

Figure L2-15: Wind Speed During Katrina and Rita at WIS-125

Day (2008)

Wind Speed (mph)

0

5

10

15

20

25

30

35

40

45

50

55

60

Wind Speed

Hurricanes Gustav and Ike (2008)

at WIS-128

Ike

Gustav

Aug. 27 Sep. 1 Sep. 6 Sep. 11

Day (2005)

Wind Speed (mph)

0

10

20

30

40

50

60

70

80

Wind Speed

Katrina

Rita

Hurricanes Katrina and Rita (2005)

at WIS-125

Aug. 27 Sep. 1 Sep. 6 Sep. 11 Sep. 16 Sep. 21 Sep. 26


2-16

Figure L2-16: Wind Speed During Gustav and Ike at WIS-125

Day (2008)

Wind Speed (mph)

0

5

10

15

20

25

30

35

40

45

50

55

60

Wind Speed

Hurricanes Gustav and Ike (2008)

at WIS-125

Ike

Gustav

Aug. 27 Sep. 1 Sep. 6 Sep. 11


2-17

L2.7 RELATIVE SEA LEVEL CHANGE

According to NOAA (http://tidesandcurrents.noaa.gov), the mean sea level (MSL) trend

at Grand Isle, LA is 9.24 millimeters/year (mm/yr) with a 95% confidence interval of +/-

0.59 mm/yr which is equivalent to a change of 0.030 ft/yr. Figure L2-17 presents the

trend based on monthly MSL data from 1947 to 2006. It should be noted that the

published information for the tide gauge at Grand Isle is a combination of data from two

tide gauges, Bayou Rigaud and East Point, about 0.9 miles apart along the northwest

shore of Grand Isle. The zero-marks on these two gauges, and thus their data sets, were

connected by leveling observations to form a continuous water level observation set

(Shinkle and Dokka, 2004).

Figure L2-17: Sea Level Rise at Grand Isle

This estimated MSL trend combines the global MSL rise and the local vertical land

motion, subsidence. A similar MSL rise trend, 0.034 ft/yr, developed by Penland and

Ramsey (1990) was used in the designs of the Raccoon (TE-48) (NRCS, 2007) and

Whiskey (TE-50) (TBS and M&N, 2007) projects.

Estimates of projected design sea level change were determined by following an 18-step

guidance developed by USACE to account for future changes in MSL (USACE, 2009). A

flowchart of the steps is presented in Figure L2-18.


2-18

Figure L2-18: 18-step Flowchart to Account for Changes in MSL (USACE, 2009)

Below are answers to each step throughout the flowchart applied to this Study. Because

the 2006 Barrier Island Comprehensive Monitoring (BICM) survey data were used in

designing this Study with estimated project start in 2012, Target Year 0 (TY0), eustatic

sea level changes were computed relative to the 2006 sea level.

Step 1: Yes Step 2

Step 2: Yes (Grand Isle, 59 years worth of data) Step 4

Step 4: Yes Step 5

Step 5: Yes Step 6

Step 6: Low/Historic MSL rise trend is 0.030 ft/year Step 7

Step 7: Standard error is 0.002 ft/year with a 95% confidence interval Step 8

Step 8: No Step 11

Step 11: Subtract 0.006 ft/year (1.7 mm) from 0.030 ft/yr which results in 0.024 ft/yr,

this is the design vertical land movement (VLM) or subsidence rate Step 12

Step 12: Low/Historic eustatic sea level rise values are

Between 2006 and 2012 (TY0) = 0.033 ft

Between 2006 and 2017 (TY5) = 0.061 ft

Between 2006 and 2022 (TY10) = 0.089 ft

Between 2006 and 2037 (TY25) = 0.173 ft Step 13

Step 13: Intermediate (NRC Curve I) eustatic sea level rise values are

Between 2006 and 2012 (TY0) = 0.055 ft

Between 2006 and 2017 (TY5) = 0.105 ft


2-19

Between 2006 and 2022 (TY10) = 0.159 ft

Between 2006 and 2037 (TY25) = 0.343 ft Step 14

Step 14: High (NRC Curve III) eustatic sea level rise values are

Between 2006 and 2012 (TY0) = 0.124 ft

Between 2006 and 2017 (TY5) = 0.246 ft

Between 2006 and 2022 (TY10) = 0.385 ft

Between 2006 and 2037 (TY25) = 0.899 ft Step 15

Steps 15 through 18 are to determine project performance and evaluate risk.

Table L2-11 presents low/historic, intermediate and high relative sea level changes for

TY0, TY5, TY10, TY25, and TY50, which combine the eustatic sea level rise and

subsidence rates. Figure L2-19 presents the three curves computed to year 2062, TY50.

Table L2-11. Estimated Design Relative Sea Level Changes

Rate Type Period Eustatic SLR,

ft

Subsidence,

ft

Relative SLR,

ft

2006-2012 (TY0) 0.033 0.144 0.177

2006-2017 (TY5) 0.061 0.264 0.325

2006-2022 (TY10) 0.089 0.384 0.473

2006-2037 (TY25) 0.173 0.744 0.917

Low/Historic

2006-2062 (TY50) 0.312 1.344 1.656

2006-2012 (TY0) 0.055 0.144 0.199

2006-2017 (TY5) 0.105 0.264 0.369

2006-2022 (TY10) 0.159 0.384 0.543

2006-2037 (TY25) 0.343 0.744 1.087

Intermediate

(NRC Curve I)

2006-2062 (TY50) 0.729 1.344 2.073

2006-2012 (TY0) 0.124 0.144 0.268

2006-2017 (TY5) 0.246 0.264 0.510

2006-2022 (TY10) 0.385 0.384 0.769

2006-2037 (TY25) 0.899 0.744 1.643

High

(NRC Curve III)

2006-2062 (TY50) 2.085 1.344 3.429


2-20

Year

Sea Level Rise (feet)

2000 2010 2020 2030 2040 2050 2060 2070 0

0.5

1

1.5

2

2.5

3

3.5

4

Low/Historic

Intermediate (NRC Curve I)

High (NRC Curve III)

Estimated Relative (Eustatic + Subsidence)

Sea Level Rise Since 2006

Figure L2-19: Estimated Relative Sea Level Rise since 2006

According to the Bruun Rule (Bruun, 1962), a sea level change results in profile

response. When sea level change occurs, beach profiles try to reach new equilibrium and

erode causing shoreline recession. Erosion due to sea level change is one of several

components that comprise shoreline erosion as a whole.

Variation in future sea level change rates yields a range of future erosion rates associated

with sea level change. To analyze how the low/historic, intermediate and high relative sea

level changes influence the future erosion rates, the Bruun Rule equation presented below

was applied to the three trends:

where

*

* ( )

W y S h B   




2-21

A berm height of 3.8 ft was determined based on the restoration design plans presented in

Section L6. The depth of closure presented in Section L2.8 was determined to be 10.5 ft.

The widths of active profiles were calculated for individual islands based on the 2006

BICM bathymetric data. The width was equivalent to the distance between contour lines

representing MHW and depth of closure. Table L2-12 presents sea level change induced

shoreline recession computed for the three trends for the 2006 to 2062 period of analysis.

The results indicate that the there is a 25% increase in erosion from low/historic to

intermediate trend, and a 107% increase from low/historic to high trend.

Table L2-12. Sea-Level Rise Induced Shoreline Recession Rates, 2006 to 2062

Shoreline Recession, ft

Island W*,ft Low/Historic

Trend

Intermediate

Trend

High

Trend

Raccoon 3,900 -8.1 -10.1 -16.7

Whiskey 2,500 -5.2 -6.5 -10.7

Trinity/East 950 -2.0 -2.5 -4.1

Wine 3,500 -7.2 -9.1 -15.0

Timbalier 2,000 -4.1 -5.2 -8.6

East Timbalier 7,000 -1.4 -1.8 -3.0

L2.8 DEPTH OF CLOSURE

The depth of closure is defined as the seaward limit of active sand transport. It is

determined by one of two methods, either empirically or using historic profile

comparisons. Both methods are employed herein and the depth of closure is defined.

WIS-125 data were utilized to compute the effective wave height, He, which is the

significant wave height that is exceeded during only 12 hours per year. The effective

wave height at WIS-125 was equal to 13.1 ft and the associated period, Te, was equal to

8.5 seconds. The STWAVE model was used to propagate the WIS-125 effective wave

closer to the shore. The calculated nearshore effective wave height and period were 7.2 ft

and 9.0 seconds, respectively. These data were used to calculate the depth of closure, hc,

by applying the empirical method developed by Birkemeier (1985):

2

2 1.75 57.9 e

c e

e

H h H

gT

     	 
 

*

*

shoreline change

sea-level change

depth of closure

berm height

width of active profile to depth of closure

y

S

h

B

W














2-22

The calculated depth of closure was equal to approximately 11.5 ft referenced to Mean

Sea Level (MSL) or approximately -10.5 ft NAVD 88.

A review of recent Louisiana projects was conducted to identify the published depth of

closure values in similar geologic settings experiencing similar coastal processes.

USACE (July 2004) computed the depth of closure equal to -12 ft NAVD 88 on Grand

Isle. SJB and CEC (2005) determined the depth of closure for the Bay Joe Wise

Headland, CWPPRA Project BA-35, Pass Chaland to Grand Bayou Barrier Restoration

Project, by conducting a field study to accurately measure the thickness of the sand

veneer over the underlying cohesive soils. Their field study and analyses yielded a depth

of closure equal to -11 ft NAVD 88. In the Whiskey Island West Flank Restoration

Project, Moffatt & Nichol used a depth of closure of -10 ft NAVD 88 (Moffatt & Nichol,

2004) which is one of the Terrebonne Basin barrier islands under consideration for

restoration.

The computed depth of closure of -10.5 ft NAVD 88 falls within the range of the

published depth of closure values and thus was chosen for this Study.


3-1

L3. SURVEYING AND MAPPING

L3.1 HISTORICAL SURVEYS

L3.1.1 Land and Water Area Surveys

Fourteen U.S.Geological Survey (USGS) land-water data sets summarizing land and

water areas from 1956 to 2006 in Coastal Louisiana are presented in Table L3-1.

According to Barras et al. (2008), these data sets were derived from (1) modified, photointerpreted National Wetlands Inventory data created for wetland habitat classifications

and (2) Landsat Thematic Mapper satellite imagery obtained from the USGS Center for

Earth Resources Observation and Science and then classified by land and water coverage.

These data sets are routinely used to provide summaries of land area and information on

land change for coastal restoration projects and were utilized to develop land loss rates

for this Study (Section L3.3).

Table L3-1. Summary of Land and Water Area Surveys in Coastal Louisiana

Survey Date Data Source

10/01/1956 National Wetlands Inventory Habitat Data

10/01/1978 National Wetlands Inventory Habitat Data

01/19/1985* Landsat Thematic Mapper Classified Imagery

01/26/1988* Landsat Thematic Mapper Classified Imagery

10/01/1988* National Wetlands Inventory Habitat Data

11/01/1990* Landsat Thematic Mapper Classified Imagery

02/24/1998* Landsat Thematic Mapper Classified Imagery

11/18/1999* Landsat Thematic Mapper Classified Imagery

10/1/2000 Louisiana Coastal Area 2000 Landsat Thematic Mapper Classified

Mosaic

10/30/2001* Landsat Thematic Mapper Classified Imagery

02/27/2002 Landsat Thematic Mapper Classified Imagery

11/07/2004* Landsat Thematic Mapper Classified Imagery

10/25/2005 Landsat Thematic Mapper Classified Imagery

10/28/2006* Landsat Thematic Mapper Classified Imagery

* denotes data sets that were used to derive land loss rates for the Terrebonne Basin Barrier Islands in

Section L3.3

L3.1.2 Bathymetric Surveys

Only a few region-wide bathymetric and topographic surveys were conducted between

1934 and 2006. Table L3-2 presents a summary of these historical regional surveys. The

National Oceanic and Atmospheric Administration (NOAA) surveys date back to 1934

and 1936. The latest and most comprehensive data set that encompassed all of the

Terrebonne Basin barrier islands is the BICM survey that was conducted in 2006 and

included bathymetric survey (UNO and USGS, 2009) and LIDAR topographic survey.

The BICM data presented in Figure L3-1 were used to develop representative profiles for

each island. These profiles were also used in the SBEACH simulations to compute


3-2

storm-induced erosion and served as the basis for calculating fill volumes required for the

restoration design plans (Section L6). Additional island specific surveys conducted as

part of the CWPPRA projects including TE-27, TE-40, and TE-50, were also reviewed,

however, few if any of the data sets were more recent than the BICM survey or

temporally consistent, thus they were not utilized for plan formulation.

Table L3-2. Summary of Bathymetric and Topographic Surveys in Terrebonne

Basin Area

Survey

Year

Data

Source Area Data Type

1934 NOAA

Caillou Bay, Lake Pelto, Southern Part of

Terrebonne Bay, Southern Part of Timbalier

Bay, and Outer Coast

Bathymetry

1936 NOAA Ship Shoal, South Ship Shoal, and South of

Timbalier Island Bathymetry

1997 Picciola &

Associates Whiskey Island TE-27 PreConstruction

1998 T. Baker

Smith Whiskey Island TE-27 PostConstruction

2004 Shaw

Coastal Timbalier Island TE-40 PreConstruction

2005 Weeks

Marine Timbalier Island TE-40 AsBuilt

2006 T. Baker

Smith Whiskey Island TE-50 PreConstruction

2006 BICM Terrebonne Basin Barrier Islands

Bathymetry

and

Topography


3-3

Figure L3-1. 2006 BICM Survey.

L3.2 SHORELINE CHANGE ANALYSIS

For more than a century, the Isles Dernieres have experienced significant and persistent

degradation and fragmentation. The average historic (18872002) rate of shoreline

change for the Isles Dernieres was -34.7 ft/yr with a range of -56.0/-17.0 ft/yr. The

average short-term (1988 to 2002) rate of shoreline change was -61.9 ft/yr with a range of

-60.5/-38.6 ft/yr (USACE, 2004c).

The average historic rates of shoreline change for the Timbalier Islands was -36.1 ft/yr

with a range of -61.2/-4.1 ft/yr between 1887 and 2002. The average short-term rate of

shoreline change was -76.4 ft/yr with a range of -179.4/-13.4 ft/yr between 1988 and

2002 (USACE, 2004c).

Utilizing the data and representative transects contained within the atlas of shoreline

changes in Louisiana (Williams et al., 1992), the following average long-term (1956

1988) rates of shoreline change were developed for each individual island:

Raccoon -28.6 ft/yr;

Whiskey -42.7 ft/yr;

Trinity/East -39.7 ft/yr;

Wine -21.6 ft/yr;

Timbalier -32.5 ft/yr;

East Timbalier -21.4 ft/yr;


3-4

It was assumed these long-term rates would be most representative of Future With

Project conditions and during the 50-year period of analysis.

L3.3 LAND LOSS RATE ANALYSIS

The USGS performed a short-term land loss trend analysis for the Terrebonne Basin,

covering the period from 1985 to 2006. A regression analysis on the data was performed.

Figures L3-2 through L3-6 present the derived regression trend lines and the 95%

confidence intervals.

Figure L3-2. Raccoon Island USGS Land Loss Trend Analysis from 1985 to 2006.


3-5

Figure L3-3. Whiskey Island USGS Land Loss Trend Analysis from 1985 to 2006.

Figure L3-4. Trinity/East Island USGS Land Loss Trend Analysis from 1985 to

2006.


3-6

Figure L3-5. Timbalier Island USGS Land Loss Trend Analysis from 1985 to 2006.

Figure L3-6. East Timbalier Island USGS Land Loss Trend Analysis from 1985 to

2006.


3-7

While the long-term shoreline change rates developed from Williams et al, (1992) were

similar to the USGS beach land loss trends, the USGS beach land gain trend for Whiskey

Island could not be verified.

Table L3-3 presents a summary of the design criteria selected for the analysis of island

habitat evolution over time including the lond-term shoreline change rates based on

Williams et al. (1992) and the USGS short-term marsh land loss trends.

Table L3-3. Historical Shoreline and Marsh Land Loss Change Rates

Island Shoreline Change Rate

(ft/yr)

Marsh Land Loss

Change Rate (ac/yr)

Raccoon -28.6 -8.4

Whiskey -42.7 -14.4

Trinity/East -39.7 -3.1

Timbalier -32.5 -10.9

East Timbalier -21.4 -23.8

The island dimensions and habitat composition of each island were determined by

applying vertical adjustments (subsidence and sea level rise) and horizontal adjustments

(background erosion and overwash) or in the case of Wine Island, background land loss,

to the existing island footprints. Utilizing the above design criteria and intermediate SLR

trend (NRC Curve I) in the analysis, the approximate years of disappearance (YOD) for

each habitat type for each island were determined (Table L3-4).

Table L3-4. Year of Disappearance Based on Shoreline & Marsh Change Rates and

Intermediate SLR Trend

Island Dune YOD Beach YOD Marsh YOD

Raccoon before 2012 2042 2052

Whiskey before 2012 2029 2043

Trinity 2032 2045 2052

East 2032 2041 2052

Wine 2013 2041 2047

Timbalier 2032 2058 after 2062

East Timbalier 2022 2055 after 2062

It should be noted that all these projections are based on long-term shoreline change and

short-term marsh land loss change rates which accounted for the presence of all three

habitat components, dune, beach, and marsh, and thus are conservative. Disappearance of

the dune component will most likely result in accelerated loss of beach and marsh and

subsequent disappearance of the beach will accelerate the loss of marsh. Therefore, the

future land loss rates are likely to increase which will result in earlier-than-projected

YOD of the islands.


3-8

L3.4 SEDIMENT BUDGET

According to Georgiou et al. (2005), in coastal Louisiana, direct measurements of

longshore transport are limited. The rates of transport are typically based on historical

studies of erosional and depositional trends as demarcated by shoreline change analyses,

sedimentation patterns in the vicinity of coastal structures, and numerical wave refraction

modeling. The general trends of sand movement along the Louisiana coast are presented

in Figure L3-7 and Table L3-5.

Figure L3-7. Longshore Sediment Transport Estimates in Coastal Louisiana. Rates are in

Cubic Meters per Year; Arrows Indicate Net Dominant Transport Direction (from

Georgiou et al., 2005).

Table L3-5. Longshore Sediment Transport Estimates in Coastal Louisiana

(after Georgiou et al., 2005)

Location From To Rate

(m3/yr)

Rate

(cy/yr)

Dominant

Direction

Holly Beach area Calcasieu Pass Sabine Pass 30,000 39,000 Westward

Isle Dernieres reach East Island Raccoon Island 33,000 43,000 Westward

Timbalier reach Raccoon Pass Cat Island Pass 11,000 14,000 Westward

Caminada Headland Belle Pass Grand Pass 146,000 191,000 Eastward

Sandy Point South Pass Grand Pass 10,000 13,000 Westward

Chandeleur Islands Southwest flank Island center 88,000 115,000 Westward

Chandeleur Islands Island center Northeast flank 66,000 86,000 Eastward


3-9

L3.4.1 Isles Dernieres

Sediment transport along the Isles Dernieres is complex, given their fragmented nature

(Georgiou et al., 2005). Overall, sediment moves in a westerly direction along the Isles

Dernieres reach, although local bidirectional transport occurs on Trinity and Whiskey

Islands. Sediment movement around Whiskey Pass is largely nonexistent. Waves

propagating through the passes break along the marsh shoreline in Lake Pelto (Stone and

Zhang, 2001). The dominance of wave-generated and flood-tidal currents facilitates

landward sand transport at many of the inlets, thereby minimizing inlet sediment

bypassing and sand nourishment of the downdrift barrier shorelines. Although net

transport rates are variable, net westward transport of approximately 78,000 cy/yr has

been derived numerically (Stone and Zhang, 2001).

L3.4.2 Timbalier Islands

According to Georgiou et al. (2005), net sediment movement along the Timbalier Islands

is to the west, and the rate increases from east to west. Subscale transport trends are

evident on both islands. East Timbalier Island is dominated by westward transport, with a

net increase in rate to the west attaining a maximum of approximately 65,000 cy/yr.

However, the sand transport system along the island has been greatly diminished because

of the extent of coastal structures in the area. The potential for transferring sand from the

Caminada Moreau Headland to East Timbalier Island is minimal, given the large width of

Raccoon Pass and the net landward movement of sand to its flood-tidal delta (Georgiou et

al., 2005).

Kulp et al. (2002) have documented extensive growth of the Raccoon Pass flood-tidal

delta during the past 10 years. This suggests that little sand bypasses the inlet but rather is

moved onshore into Timbalier Bay. Similarly, transport trends occur along Timbalier

Island with a net increase in the rate along the eastern flank of the barrier island to

approximately 65,000 cy/yr (Georgiou et al., 2005). Conversely, the rate decreases to the

western end of the island. This pattern suggests that sand eroded from the eastern flank is

transported to the west where it is deposited along the west flank of the barrier as well as

in Cat Island Pass (Georgiou et al., 2005). Bypassing of sand across Little Pass Timbalier

is minimal. Waves propagate through this inlet prior to breaking in Timbalier Bay. In

addition, dense armoring along East Timbalier Island decreases the longshore export of

sediment to the west (Georgiou et al., 2005).

L3.5 AERIAL PHOTOGRAPHY

Aerial imagery acquired in 2008 is the latest set of aerial photographs that encompassed

all of the Terrebonne Basin barrier islands. The set was developed primarily to support

multi-use applications including wetlands restoration efforts conducted by CWPPRA.

The restoration design templates were superimposed on the 2008 aerial photography to

create the conceptual plans (Annex L).


4-1

L4. ENVIRONMENTAL

L4.1 ENVIRONMENTAL SETTING

L4.1.1 Hydrology

The Mississippi River and its distributaries historically provided immense volumes of

land-building sediment and nutrients throughout Louisianas coastal areas. Levee

construction activity along the Mississippi River in coastal Louisiana began as early as

the 1700s. By the early 1900s the levee system along the River was nearly complete,

protecting the surrounding areas by reducing the number of overbank flooding events.

The flood protection afforded by the levee system allowed for increased economic

development and human habitation in the coastal areas. With this development came the

construction of roads, railways, ports and harbors, oil and gas access canals within the

wetlands, and drainage projects. Consequences of these activities were disruption of the

natural hydrologic and deltaic cycles, which in turn deprived surrounding wetlands of

sediment- and nutrient-rich floodwaters, leading to increases in subsidence and land loss

(USACE, 2004a).

The Terrebonne Basin drainage area encompasses approximately 1,455 square miles.

Major navigation channels within the basin are the Atchafalaya River, Wax Lake Outlet,

Houma Navigation Canal (HNC), Gulf Intracoastal Waterway (GIWW), and Lower

Atchafalaya. These navigation channels introduce and/or compound marine influences in

many of the interior coastal wetlands and water bodies within the Terrebonne Basin

(USACE, 2004a).

The Terrebonne Basin wetland communities experience different hydrological influences.

The eastern portions of the basin are hydrologically isolated from the influence of the

major sediment rich waters of the Atchafalaya and Mississippi Rivers. The same is true

for the northwestern portions, both above and below the GIWW, where the hydrologic

influence comes from a widely-variable pattern of Atchafalaya River backwater effect,

rainfall runoff events, and marine processes. Conversely, the southwestern portion of the

basin receives nourishment from the Atchafalaya River and has some of the lowest land

loss rates in the state (USACE, 2004a).

The Terrebonne Basin is separated from the GOM by the Isle Dernieres and the

Timbalier barrier islands. These barrier islands protect the interior wetlands by buffering

wave action and storm surge. The islands are constantly changing due to normal coastal

hydrologic processes, including water-level changes induced by tides and sea level

change, currents, and wave action, as well as subsidence. With the passage of tropical

storms and hurricanes, these processes are magnified. The net effect of the interaction of

the physical process is the control of the amount and location of these forces that move

sediment and modify the islands morphology and habitats (USEPA, 1997).


4-2

L4.1.2 Habitat Types

The basic coastal wetland habitats within the Terrebonne Basin are typically described as

swamp, fresh marsh, intermediate marsh, brackish marsh, and saline marsh (Day et al.,

1989; Mitsch and Gosselink, 2000), while those typically found in the Study Area are

brackish marsh and saline marsh. As their designations imply, these habitats are strongly

influenced and characterized by the salinity regime of the surface water.

L4.1.3 Land Cover

There are approximately 70,480 acres within the LCA TBBSR Study Area. The USGS

vegetation classification descriptions within the Study Area are provided below and

acreages of the vegetation classifications are presented in Figure L4-1.

Bare Land (Rock/Sand/Clay) - Barren areas of bedrock, desert pavement, scarps,

talus, slides, volcanic material, glacial debris, sand dunes, strip mines, gravel pits

and other accumulations of earthen material. Generally, vegetation accounts for

less than 15% of total cover.

Estuarine Aquatic Bed - Includes tidal wetlands and deepwater habitats in which

salinity due to ocean-derived salts is equal to or greater than 0.5% and which are

dominated by plants that grow and form a continuous cover principally on or at

the surface of the water. These include algal mats, kelp beds, and rooted vascular

plant assemblages.

Estuarine Emergent Wetland - Includes all tidal wetlands dominated by erect,

rooted, herbaceous hydrophytes (excluding mosses and lichens) and all such

wetlands that occur in tidal areas in which salinity due to ocean-derived salts is

equal to or greater than 0.5% and that are present for most of the growing season

in most years. Perennial plants usually dominate these wetlands.

Estuarine Scrub/Shrub Wetland - Includes all tidal wetlands dominated by woody

vegetation less than 5 meters in height, and all such wetlands that occur in tidal

areas in which salinity due to ocean-derived salts is equal to or greater than 0.5%.

Total vegetation coverage is greater than 20%.

Mixed Forest - Areas dominated by trees generally greater than 5 meters tall, and

greater than 20% of total vegetation cover. Neither deciduous nor evergreen

species are greater than 75% of total tree cover.

Palustrine Forested Wetland -Includes all tidal and non-tidal wetlands dominated

by woody vegetation greater than or equal to 5 meters in height and all such

wetlands that occur in tidal areas in which salinity due to ocean-derived salts is

below 0.5%. Total vegetation coverage is greater than 20%.

Palustrine Scrub/Shrub Wetland - Includes all tidal and non-tidal wetlands

dominated by woody vegetation less than 5 meters in height, and all such

wetlands that occur in tidal areas in which salinity due to ocean-derived salts is

below 0.5%. Total vegetation coverage is greater than 20%. The species present

could be true shrubs, young trees and shrubs or trees that are small or stunted due

to environmental conditions.

Scrub/Shrub - Areas dominated by shrubs; less than 5 meters tall with shrub

canopy typically greater than 20% of total vegetation. This class includes true


4-3

shrubs, young trees in an early successional stage or trees stunted from

environmental conditions.

Unconsolidated Shore - Unconsolidated material such as silt, sand, or gravel that

is subject to inundation and redistribution due to the action of water.

Characterized by substrates lacking vegetation except for pioneering plants that

become established during brief periods when growing conditions are favorable.

Erosion and deposition by waves and currents produce a number of landforms

representing this class.

Water - All areas of open water, generally with less than 25% cover of vegetation

or soil.

Based on the USGS 2001 land cover data set of Louisiana, the majority of the Terrebonne

Basin barrier islands land, approximately 2,461 acres, is classified as unconsolidated

shore. The other two dominant land types are estuarine emergent wetland, approximately

2,033 acres, and bare land, approximately 977 acres. The remaining land types

composing the Terrebonne Basin barrier islands, excluding open water, account for

approximately 68 acres.


August, 2009

Figure L4-1. Land Cover Classifications.


4-5

L4.1.4 Wildlife Resources

Coastal Louisiana's wetlands support neotropical migratory, and other avian species, such as rails,

gallinules, and numerous wading birds and songbirds. In addition, they support alligators and

smaller reptiles, plus mammals, ranging from small furbearers, to rabbits, coyote, and deer.

Coastal Louisiana has the Nations largest concentrations of colonial nesting wading birds and

seabirds. One hundred ninety-seven colonies of wading birds and seabirds (representing 215,249

pairs of nesting birds) were observed in coastal Louisiana during a 2001 survey (USACE, 2004b).

Louisiana coastal wetlands provide essential stopover habitat for migratory birds on their annual

migration route. Without stopover sites to provide adequate food supply for the quick

replenishment of fat reserves, shelter from predators, and water for rehydration, migratory birds

may be negatively affected. It is estimated that approximately 382 species of finfish, shellfish,

reptiles, amphibians, and mammals, as well as 353 species of birds (of which 185 are annual

returning migrants) spend all or part of their life cycles in the Barataria-Terrebonne estuary

(USACE, 2004a).

Historically, the extreme land and shoreline erosion in coastal Louisiana has had negative impacts

on key physical, chemical, and biological processes, resulting in the conversion of or reduction in

nursery habitat, waterfowl wintering habitat, neotropical migrant nesting and feeding areas,

vegetative habitat and communities, soil formation and organic matter accretion, and water quality

(USACE, 2004a). For several decades, these changes have resulted in continued shifts in habitat

complexity and species diversity within the Terrebonne Basin, and therefore a continuation in

overall wildlife population decline is expected (USACE, 2004b).

L4.2 HAZARDOUS, TOXIC AND RADIOACTIVE WASTE

A Phase I Environmental Site Assessment (ESA) of the Study Area was conducted and recorded in

HTRW Phase I Environmental Site Assessment, Terrebonne Basin Barrier Shoreline Restoration

Project, Contract No. 2503-07-15 for Louisiana Office of Coastal Protection and Restoration (SJB,

Unpublished).

The purpose of this Phase I ESA is to identify historical or overt physical evidence of current or

past activities or materials at the Site and its immediate vicinity which constitute "recognized

environmental conditions"(REC) defined by the ASTM Standard to be "the presence or likely

presence of any hazardous, toxic, and radioactive substances or petroleum products on a property

under conditions that indicate an existing release, a past release, or a material threat of a release

into structures on the property or into the ground, groundwater, or surface water of the property."

This Phase I ESA is consistent with the scope of work provided by the USACE and protocols

established in the American Society for Testing and Materials publication "Standard Practice for

Environmental Site Assessments: Phase I Environmental Site Assessment Process for Forestland

or Rural Property" (Designation E 2247-08, referred to as the ASTM Standard) to provide "due

diligence" for rural transactions. However, it will require a second Study Area visit and interviews

related to ASTM Standard to be conducted at a later date that is closer to expected time of

construction for the year 2012 (SJB, Unpublished).


4-6

On November 20, 2008, SJBs environmental specialists performed an aerial reconnaissance of the

Study Area and a field visit on July 27-30, 2009 at selected locations throughout seven major

barrier islands that included East Timbalier Island, Timbalier Island, Wine Island, East Island,

Trinity Island, Whiskey Island, and Raccoon Island. Photographs were taken documenting field

observations.

SJB obtained historical documentation of the Study Areas past uses and activities in order to

identify possible recognized environmental conditions. Sources of historical documentation

included historical aerial photographs, topographic maps, and Environmental Database Report.

SJB performed a Phase I ESA in conformance with the scope and limitations of ASTM Standard E

1527-05 on the Isle Dernieres and the Timbalier Islands located within Terrebonne Basin in

Terrebonne Parish, Louisiana. Any exceptions to or deletions from this practice were described.

The Emergency Response Notification System (ERNS) entries were thought to represent historical

REC. After reviewing the monitoring reports, SJB found indications of release of petroleum

products for all 6 incidents. These releases were addressed in compliance with Environmental

Protection Agency (EPA) regulations. Therefore, the ERNS entries were considered historical

REC. Since SJB was unable to inspect the production facilities at this time; current REC(s) were

unable to be identified within the Study Area. However, without proper investigation of these

facilities, current REC(s) may be present within the project area near or within these production

facilities (SJB, Unpublished).

Based on historical sources that were provided dating back to the late 1800s, environmental

database reviews, and a limited inspection, SJB could not adequately identify any current and

historical recognized environmental conditions as defined in ASTM standard E 2247-08 at that

time.

L4.3 GEOLOGIC SETTING

L4.3.1 Geomorphic and Physiographic Setting

The morphology and integrity of the Terrebonne Basin barrier island reach is directly related to the

deltaic processes operating on the coast of Louisiana. The Deltaic Plain consists of a generally

fine-grained sedimentary package deposited within a wide variety of fluvial, deltaic, and coastal

depositional environments (USACE, 2004c).

L4.3.1.1 Deltaic Cycle

The geologic development of coastal Louisiana and the resulting coastal landscape were dependent

upon shifting Mississippi River courses and are influenced by the orderly progression of events

related to the "deltaic cycle." The deltaic cycle is a dynamic and episodic process alternating

between periods of delta-building with seaward advancement (progradation) of deltas, and their

subsequent landward retreat (degradation). The Mississippi River has changed its course several

times during the last 7,000 years. Each time the Mississippi River has built a major delta it has

eventually abandoned that river course in favor of a shorter, more direct route to the GOM. As

deltas are abandoned, the seaward edges are reworked into barrier headlands and barrier islands.

Subsequently, the wetland complex behind the headlands and islands, without a significant and


4-7

continuous source of sediment and nutrients, eventually succumbs to subsidence and becomes

submerged by marine waters.

The Deltaic Plain is composed of 6 major delta complexes: 2 prograding and 4 degrading (Figure

L4-2). The Atchafalaya and Modern Delta (Plaquemine/Balize) complexes are active and

prograding, while the Maringouin, Teche, St. Bernard, and Lafourche complexes are inactive.

Present day Terrebonne Basin is the result of the Lafourche delta formation, through seaward

advancement from deposition of Mississippi River distributary sediment, the subsequent delta

degradation and detachment, and the reworking of seaward headlands to form barrier islands

(USACE, 2004a).


Figure L4-2. Mississippi River Deltaic Plain.


4-9

L4.3.1.2 Delta Advancement

The Mississippi River Deltaic Plain wetland ecosystem developed as a result of delta-building

processes, during which sea level conditions were relatively stable. The deltaic cycle is initiated

when the Mississippi River, enters an open water body, such as a coastal lake or bay, which slows

the velocity of the rivers flow, thus limiting the rivers ability to transport sediment.

Consequently, most of the larger-grained sediment carried by the river drops out of the water

column and falls to the bottom. Over time, the river deposits enough sediment to create land,

which then becomes colonized by wetland plants. The organic deposition from additional riverborne sediment and decomposing wetland vegetation are the primary factors behind the landbuilding process. In this fashion, large expanses of wetlands, or deltas, form and extend seaward

between the distributaries, or "fingers" of the delta, as long as the river continues to supply

freshwater, nutrients, and land-building sediment (USACE, 2004a).

L4.3.1.3 Delta Abandonment

As a delta grows and extends into the GOM, the river stage gradually heightens. Eventually, the

river breaks through a weak point in its bank and/or shifts its main water flow into a distributary,

thus providing a shorter route for the river to travel to the Gulf. About every 1,000 years, the

Mississippi River altered its path to the GOM, sometimes flowing down the western portion of the

current Deltaic Plain and sometimes down the eastern portion. Whenever the river changed

course, the location of active delta building also changed. Areas that no longer received sufficient

volumes of freshwater laden with sediment and nutrients began to succumb to subsidence, while

those areas that received the majority of river water input began a new phase of delta building.

These meandering changes in the course of the Mississippi River and accompanying shifts in

centers of sediment deposition are responsible for the distribution of deltaic sediment along the

entire Louisiana coast and into Texas.

Once the Mississippi River altered its course and began to form a new delta, tidal influences and a

lack of sediment and nutrient inputs slowly degraded the previously active delta location. Over

time, the interior wetlands were submerged and marine influences reworked the gulfward edge of

the delta into a series of barrier headlands. As the shoreline facing the GOM matured, and as the

marshes behind the shoreline broke up and eventually disappeared, the barrier headlands

transitioned into barrier islands.

Figure L4-3 presents the three-stage geomorphic model that summarizes the genesis and evolution

of transgressive depositional systems in the Mississippi River Deltaic Plain (USACE, 2004a).


Figure L4-3. Three-Stage Geomorphic Model


4-11

The present Louisiana barrier islands are the product of the coupling of the deltaic cycle with the

complex interactions between storm events, longshore sediment supply, anthropogenic events,

coastal structures, and inlet dynamics that have all contributed to island formation, migration, and

erosion.

L4.3.2 Soils

The deltaic and Chenier Plains of coastal Louisiana consist of soils that can be divided into 6

primary associations. These soils are primarily mineral deltaic, or mineral coastal deposits formed

from alluvial or aeolian processes. The soils that exist nearest to the coast may also be formed or

deposited by marine processes and sediments. The 6 coastal associations often contain soils with

organic matter in the upper horizon, or throughout the whole profile (USACE, 2004b).

Examples of these soil types are found along the Isles Dernieres and Timbalier Islands barrier

shorelines. The seaward edges of these islands are linear or curvilinear forms consisting of loamy

fine sand (fluid mineral soils) formed by means of marine reworking. The back-barrier saltwater

marshes consist of level, very poorly drained soils that have a mucky surface layer (high levels of

organic matter), and a mucky or clayey underlying material (USDA, 2007).

Specific geotechnical investigations including test borings were conducted on the islands as part of

the CWPPRA project designs. For Whiskey Island, auger borings taken on the beach and dune

revealed fine sand with shell fragments while the back-bay and marsh borings indicated soft clays

and silty clays with lenses of sand, silt and shell comprised the upper 65 ft, and were underlain by

medium stiff pro-delta clays with silt and sand lenses (LDNR, 2007). On Raccoon Island, the

results of the test borings indicated that generally the soils are loose sands underlain by weak

compressible clays to depths of over 100 ft. The upper 12 to 15 feet was classified as fine sand and

silt, underlain by soft clays and silty clays to 50 ft (NRCS, 2007). These soil types are

characteristic of the Terrebonne Basin barrier islands.


5-1

L5. GEOTECHNICAL INVESTIGATIONS

L5.1 BORROW AREA INTRODUCTION

L5.1.1 Introduction and Sediment Search Effort

The search for sediment resources to repair and restore the Louisiana barrier islands has

been underway for decades. For both the Isles Dernieres and the Timbalier Island

reaches, this expansive search effectively commenced in the early 1980s, undertaken by

the Louisiana Geological Survey. The findings were summarized in a 1991 report, whose

authors analyzed the geophysical data and geotechnical samples, reporting on 55

nearshore sand body targets (Suter et al., 1991). Twenty-three of these were in the

vicinity (inshore, between, and offshore) of the Terrebonne Basin Barrier Islands. Their

initial estimates of available sediment volumes indicated the presence of adequate

quantities of sediment for both beach/dune and marsh creation. Subsequent continuing

and expanded research has been summarized for a volume dedicated to restoration of

Louisianas barrier islands and wetlands (Kulp et al., 2005). While the estimates of

available sand and marsh fill sediment appear impressive, they often do not consider the

web of petroleum production and processing infrastructure, primarily pipelines, which

extends from the interior bays between and beneath the barrier islands to well out onto

the continental shelf. In addition, required magnetometer and sonar surveys may uncover

shipwrecks and other archeological features that must be avoided. When those cultural

resources and their surrounding buffer zones are accurately mapped, and consideration

is given to the issue of excavation side slope stability versus depth of excavation, the

volumes of sediment that are actually available may be significantly reduced (Nairn et al.,

2004, 2005). In addition, the shapes of the proposed borrow areas may make dredging

more technically difficult.

The consensus of numerous studies regarding the potential restoration of the Isles

Dernieres and Timbalier Islands holds that available sand resources are limited and those

that have been identified for restoration projects are typically constrained by the presence

of petroleum extraction and distribution infrastructure.

L5.1.2 Available Project Documentation

Khalil et al. (2010) mapped numerous potential sediment borrow areas along the

Louisiana Gulf coast, from South Pass west to Sabine Pass. Six large-volume areas were

delineated off the Terrebonne Basin Barrier Islands. Three of these are on the Outer

Continental Shelf (OCS) and three are in State waters, closer to shore. The latter

included a group of five small borrow areas associated with a Timbalier Island project,

three north of the island, in the bay, and two to the south.

Designation and use of both inshore and offshore borrow areas has been associated with

individual restoration projects for many years. Eleven CWPPRA projects have been

completed in the Study Area since 1996 and eight of them involved dredging fill material

from nearby borrow areas. These projects were described the December 2008 LCA

TBBSR Study Feasibility Report (SJB and CEC, 2008). The criteria for evaluating


5-2

potential borrow sites/sources have evolved over time. Several early projects utilized

borrow sites that were in close proximity to the restoration sites, either in the bay to the

north or an adjacent pass. While such areas may be convenient, and relatively

inexpensive to exploit, they pose several potential problems: if too close to an island they

can function as sinks and facilitate sediment loss from adjacent shorelines and shoals, and

their depth and breadth can lead to unexpected changes in wave dynamics, also leading to

shoreline erosion. As a result of these problems, the State of Louisiana has discouraged

use of bay and pass borrow areas.

Seven CWPPRA projects have already utilized borrow sites in the vicinity of the

Terrebonne Basin Barrier Islands. The projects constructed beach, dune, and/or marsh

habitats on Whiskey, Trinity, East, Timbalier, and East Timbalier Islands, and one of

them also closed the breach between Trinity and East Islands. One borrow area was

located offshore from Whiskey Island, and the rest were located either in passes or in

Lake Pelto, north of the islands. To ascertain the fates of these borrow areas, the

available documentation was reviewed including project information sheets, status

reports, completion reports, monitoring plans, monitoring reports, and environmental

assessments. In addition, where information has been lacking, there has been personal

communication with the PDT Team.

Three CWPPRA projects have proposed using borrow sites that are logical sources of

sediment for the LCA TBBSR Study. The projects are: Ship Shoal Whiskey Island West

Flank Restoration (TE-47), Raccoon Island Shoreline Protection/Marsh Creation, Phase 2

(TE-48), and Whiskey Island Back Barrier Marsh Creation (TE-50). TE-50 was recently

completed.

During PDT meetings and conference calls from mid- to late-2009, two additional

potential sand sources were proposed and discussed. The first was reported as an

accumulation of sand in Cat Island Pass, located off the west end of Timbalier Island. It

was assumed that it was comprised of sediment that had been transported from Timbalier

by normal coastal processes. The second proposed source was the HNC Channel, where

it crosses beneath the open water of Terrebonne Bay and extends offshore south of Cat

Island Pass.

L5.1.3 Offshore Borrow Areas

As previously stated, the starting point for the PDTs borrow area search effort was the

information compiled by Khalil et al. (2010). Their tabular compilation included the

location of the borrow area, estimated volume of available fill material, volume of

material already dredged from the borrow area, and pertinent geotechnical and

geophysical references. Figure L5-1 presents the Terrebonne Basin portion of the Khalil

and Cantu map.


Figure L5-1. Coastal Louisiana Borrow Areas, Courtesy Khalil et al., 2010.


5-4

L5.1.3.1 Ship Shoal

Ship Shoal is an east-west elongate sand body approximately 42 miles long and four

miles wide located approximately five miles south of the Isles Dernieres. Its east-west

extent runs from about 15 miles west of Raccoon Island eastward to the area of Cat Island

Pass. It has been characterized as one of a number of submerged relict deltaic headlands,

deposited during earlier stages in the evolution of the Mississippi Delta (Kulp et al.,

2005). As the need for material to stabilize and restore the shorelines and marshes of

Coastal Louisiana has increased in intensity, Ship Shoal has been studied extensively in

recent years because of its size and large volume of sandy sediment. Analyses have

indicated that greater than 90% the sediment in Ship Shoal is quartz sand (Kulp et al.,

2001). Most relevant to the LCA TBBSR Study are studies of the potential borrow sites

referred to as Ship Shoal Blocks 88 and 89, located south of Raccoon Island, and South

Pelto Blocks 12 and 13, located on the eastern end of Ship Shoal, south of Trinity-East

Island. Extensive geophysical and archaeological studies of the area of these blocks were

undertaken in 2003. Analyses, including geotechnical data previously acquired by the

Louisiana Geological Survey and the USGS, were presented in two 2003 reports from the

U.S. Environmental Protection Agency (EPA): the first covering portions of Ship Shoal

Blocks 87, 88, 89, 94, and 95 and the second South Pelto Blocks 12, 13, 14, 18 and 19,

that included High Resolution Geophysical and Archaeological Surveys (C&C, 2003a

and 2003b).

L5.1.3.2 Raccoon Island Borrow Area

The eastern end of Raccoon Island has been stabilized by a field of eight shore-parallel

breakwaters since 1997, when they were initially installed as a demonstration project

(TE-29 project). The field was extended by an additional eight breakwaters in 2005 (TE48 project, Raccoon Island Shoreline Protection/Marsh Creation). The presence of two

buried distributary channels off Raccoon Island was noted by Suter et al. (1991). During

the course of geological investigations for the TE-48 project, a portion of one buried river

channel was located approximately four to six miles south of Raccoon Island. The

channel is sublinear, oriented along a northwest/southwest alignment, with a width

ranging from 500 to 750 ft, and at least 20,000 ft in length. Analysis of vibracore

samples from the sediment within the delineated channel found it to be mixed sediment

with an average grain size of 0.10 mm, with the coarse fraction averaging 16.5% of the

material, and an average of 83.5% finer material, potentially suitable for marsh fill. The

borrow area designed for the TE-48 project was 8,850 ft long, from 440 to 890 ft wide,

with a maximum cut depth of 20 ft and an estimated volume of 830,000 cubic yards (cy).

The estimated volume of the entire borrow area is 3.42 mcy (SJB et al., 2006).

L5.1.3.3 Whiskey Island Back-Barrier Marsh Borrow Areas

According to LDNR (2007), Ocean Surveys, Inc. (OSI) carried out an extensive

geophysical and geotechnical search in an LDNR-designated potential offshore borrow

area south of Trinity and Whiskey Islands and Whiskey Pass. Their analyses of the subbottom profiles for strata indicative of sandy material and finer, silt-clay material led to

delineation of three potential offshore borrow areas, assumed to contain suitable sediment


5-5

for beach, dune, and marsh restoration. OSI then conducted a vibracore investigation of

the three subareas within the Khalil and Cantu (2008) Borrow Area 7, designated as

Areas 1, 2, and 3.

Excluding avoidance areas, based on pipeline corridors and other magnetic anomalies,

the estimated volumes of sand available in Subareas 2a and 3a are 1.15 and 4.72 mcy,

respectively. Above the identified sand strata in Areas 2 and 3 is a layer of overburden,

consisting of silt and clay, suitable for marsh creation. The estimated volumes of

overburden available in Subareas 2a and 3a are 3.05 and 7.97 mcy, respectively (LDNR,

2007).

OSI also estimated the volumes of overburden and sand contained in Subareas 3b and 3c.

Subarea 3b contains approximately 730,000 cy of overburden and 1.13 mcy of sand.

Subarea 3c contains approximately 180,000 cys of overburden and 200,000 cy of sand,

however those areas were not subjected to cultural resource surveys (magnetometer and

side-scan sonar studies).

L5.1.3.4 New Cut Dune and Marsh Borrow Area

Initially, a considerable effort was expended characterizing a borrow site in Wine Island

Pass, one that was estimated to contained more than two million cubic yards (mcy) of

suitable sediment (Armbruster, 2000). Strong local opposition to the use of that site

resulted in its withdrawal from consideration. An alternate borrow area was subsequently

designated three miles offshore. The available ecological review and the project status

reports did not provide any detailed information on the borrow site finally utilized for this

project. However, sufficient detail was obtained from the bid documents to address it.

Finkl et al. (2005) estimated that the borrow area contained 4.2 mcy of material.

L5.1.3.5 Timbalier Island Borrow Areas

As previously discussed, Khalil and Cantu (2008) showed five borrow areas, numbered

9a through 9e, in the vicinity of Timbalier Island.

L5.2 BORROW AREA CHARACTERISTICS AND SCREENING CRITERIA

The criteria that the PDT used to screen potential borrow areas were a combination of

physical, geographic, and socioeconomic characteristics.

L5.2.1 Location Relative to Depth of Closure

The depth of closure represents the offshore extent of the active beach face, thus

sediment inshore of it must be considered as part of the sand budget for that particular

reach, and conservation of that resource is essential in a sand-starved system, such as the

Louisiana coast. Excavations inshore of the depth of closure become sinks that

accumulate sediment that is normally part of the longshore/onshore and offshore

transport system. Of concern here is conservation of the sand resources and avoidance of

interference with coastal processes from excavating these resources for island restoration.


5-6

Recognition of the sand-starved status of Coastal Louisiana resulted in development of a

hydrogeomorphic planning objective of the LCA 2004 Plan, specifically to import

sediment from sources outside of the estuarine basins (i.e., beyond the depth of closure)

(LCA, 2004). Therefore the borrow areas shall be located seaward of the depth of closure

which was defined in Section L2 to be equal to -10.5 ft NAVD 88.

L5.2.2 Borrow Area Geotechnical and Geophysical Data, Analyses,

and Interpretation

The sediment particle size ranges and distributions should match the characteristic of the

beach and dune where it will be placed. In the case of marsh material, there should be

variability in particle size to match the existing marsh environment. The sediment should

be compatible with the sediment at the fill placement site to avoid accelerated loss of

sand and changes in beach face morphology. To maximize efficiency of the excavation

process, the core data and seismic profiles should indicate adequate stratum thickness for

efficient mining. If the strata are too thin, the excavation process can create a blend of

material that may be compatible with the native sediment at the fill placement site, but

that must be determined from the data, and not left to chance.

L5.2.3 Borrow Area Volumes

The sediment volume must equal or exceed the estimate of volume needed to complete

the LCA TBBSR Study.

L5.2.4 Cultural Resources/Petroleum Infrastructure Clearance

Cultural resources can be significant constraints. Shipwrecks and pipelines must be

avoided. Side-scan sonar and magnetometer survey are a requisite for clearance by the

State Historic Preservation Office (SHPO) and other involved agencies. Use of borrow

areas must often be approved or cleared by the Bureau of Ocean Energy Management,

Regulation, and Enforcement (BOEMRE), formally the Department of Interior, Materials

Management Service (MMS) or the LDNR.

L5.2.5 Technical Difficulty

Borrow site location factors, such as water depth and distance to disposal site, can dictate

use of hopper or cutterhead dredge. Depending on the alternative, different measures are

required to transfer the dredged material to the disposal site(s). The issue involves

double handling of dredged material. If the disposal site depth is inadequate to

accommodate the draft of a hopper dredge it may require offshore dumping and redredging by cutterhead or offshore booster pumps to move material ashore. Inadequate

depth at the borrow area to accommodate a hopper dredge may require use of a

cutterhead dredge. The latter type is less seaworthy than the former, thus introducing

heightened concern about weather-related production interruptions.


5-7

L5.2.6 Navigation Features

The HNC, its channel across Terrebonne Bay, and the Bayou Grand Caillou Safety

Fairway are Federally-designated waterways in which interference with navigation is an

issue. Constraining use of such channels with fill material, structures, or equipment, even

temporarily, requires advance notice and authorization from the USACE.

L5.2.7 Mining Impacts

Offshore shoals, bypassing bars, and similar bodies interact with the waves that pass

across them. Waves can be attenuated and their directions changed, so that the wave

energy that impacts a nearby shoreline is changed. Depending on the wave length,

height, and direction, the changes can be beneficial or detrimental, resulting in either

accretion or erosion of the shoreline. The results of wave refraction modeling, based on

wind and wave direction and intensity data, must be carefully analyzed to ensure that

excavation of the borrow area does not result in detrimental changes to the shoreline or

nearby passes.

L5.3 INITIAL BORROW AREA SCREENING

The locations of the borrow areas considered in the LCA TBBSR Study are presented in

Figure L5-1. The initial screening was finalized during the PDT meeting on August 11,

2009. The PDT Team had previous discussions with CPRA staff regarding potential

borrow areas and their supporting information, and this was incorporated into the

screening process. The initial screening criterion applied was borrow area location.

Table L5-1 and Figure L5-2 present the known information and depict the nine potential

borrow areas that passed the initial screening. It should be noted that the numbers

assigned to each area differ from those presented in the Khalil and Cantu (2008) map

(Figure L5-1) because several previously unnumbered areas were identified and added to

the evaluation.

The potential borrow areas that were eliminated during this screening were:

Timbalier Island Dune and Marsh Restoration (TE-40) borrow areas 9a through

9d, as shown on the Khalil and Cantu (2008) map. They were eliminated because

all four are well inshore of the depth of closure isobath. Note that area 9e was

retained.


5-8

Table L5-1. Initial Borrow Area Screening Table

Map

ID Location

Water

Depth,

ft

Sed.

Size,

mm

Type Thickness,

ft

%

Material

Potential

Available

Volume,

mcy

Applicability

Cultural

Resources

Survey Data

Cultural

Resources

Clearance

Whiskey

Island

TE-50 Area 1

< 16 -

Mixed,

silt, clay

(overbu

rden)

N/A N/A N/A Marsh N/A

1

Whiskey

Island

TE-50 Area 1

- Sand 0.8-2.4 N/A N/A Beach/

Dune N/A

Whiskey

Island

TE-50 Area 2

(subarea 2a)

16-20 -

Mixed,

silt, clay

(overbu

rden)

8-9.5

6-47%

sand

13.5-

66.5%

silt

20.7-

83.4%

clay

0.29* Marsh

1 2006 Chirp,

magnetic, and

side scan sonar

surveys by OSI 2

Whiskey

Island

TE-50 Area 2

(subarea 2a)

-

0.105

-

0.135

Sand 2.5-7.6 90%

sand 0.79** Beach/

Dune

1 2006 Chirp,

magnetic, and

side scan sonar

surveys by OSI

Whiskey

Island

TE-50 Area 3

(subarea 3a)

16-22 -

Mixed,

silt, clay

(overbu

rden)

3.5-17.4

20%

sand

30.0-

49.7 silt

27.4-

68.7%

clay

7.97 Marsh

1 2006 Chirp,

magnetic, and

side scan sonar

surveys by OSI

Whiskey

Island

TE-50 Area 3

(subarea 3a)

-

0.107

-

0.166

Sand 2.5-14 80%

sand 4.72 Beach/Dune

1 2006 Chirp,

magnetic, and

side scan sonar

surveys by OSI

Whiskey

Island

TE-50 Area 3

(subarea 3b)

16-22 -

Mixed,

silt, clay

(overbu

rden)

7.5

6-47%

sand 0.73 Marsh N/A

Whiskey

Island

TE-50 Area 3

(subarea 3b)

-

0.113

-

0.135

Sand 2.7-6.4 80%

sand 1.13 Beach/Dune N/A

Whiskey

Island

TE-50 Area 3

(subarea 3c)

16-22 -

Mixed,

silt, clay

(overbu

rden)

8

22%

sand 0.18 Marsh N/A

3

Whiskey

Island

TE-50 Area 3

(subarea 3c)

- 0.120 Sand 8.5 85%

sand 0.20 Beach/Dune N/A


5-9

Map

ID Location

Water

Depth,

ft

Sed.

Size,

mm

Type Thickness,

ft

%

Material

Potential

Available

Volume,

mcy

Applicability

Cultural

Resources

Survey Data

Cultural

Resources

Clearance

4 New Cut

TE-37 Area 13-16 - Sand 6 - 2.5*** Beach/

Dune

vibracore and

magnetic

surveys

5

Raccoon

Island

TE-48

22.5-31 0.09-

0.13

Mixed

sand,

silt, clay

10-20

16.5-

24.6%

above

#200

sieve

2.4 Marsh

2 2008 remote

sensing side

scan and

magnetometer

surveys by

Goodwin

BOEMRE

Lease

Pending

(NRCS)

6 South Pelto

blocks 12&13 26-48 0.15-0.20 Sand 13-20 < 5%silt 21.3 Beach/

Dune

3 2003 seismic,

sonar, and

magnetic

surveys by

C&C

BOEMRE

Grandfathering

Pending

(CPRA)

Ship Shoal

block 88 17-23 0.19 Sand 10-19 < 5%silt 17.3 Beach/Dune

4 2003 seismic,

sonar, and

magnetic

surveys by

C&C

5 2004

echosounder

and vibracore

surveys and

sediment

sampling

analysis by STE

7

Ship Shoal

blocks

88,89,94,&95

16-32 0.19 Sand 8-12 < 5%

silt 47.5 Beach/

Dune

4 2003 seismic,

sonar, and

magnetic

surveys by

C&C

BOEMRE

Grandfathering

Pending

(CPRAR)

8 Western Ship

Shoal

blocks

84,85,98,&99

9-15 N/A Sand 13 N/A 124 Beach/

Dune N/A

9 Cat Island Pass 10-20 N/A Sand 5-10 silty

sand 6.6 Beach/Dune N/A

N/A denotes data not available

* Excludes a volume of 2.76 mcy of overburden material estimated for Whiskey Island TE-50 Project.

** Excludes a volume of 360,000 cy of dune material estimated for Whiskey Island TE-50 Project. *** Available volume based upon personal communication with CPRA, August 2009.  Excludes a volume of 1 mcy estimated for Raccoon Island TE-48 Project.

 Excludes a volume of 7 mcy estimated for Caminada Headland Restoration Project.  Harry. H. Roberts and DeWitt Braud. March 2009. Results of the Western Ship Shoal Geophysical

Survey: Evaluation of Sand Available for Coastal Restoration.

 Estimated based on September 2003 geologic profiles obtained from USACE through personal

communication.

1 Ocean Surveys, Inc. (OSI) 2006. Hydrographic, Geophysical and Geotechnical Survey Program Whiskey

Island Back Barrier Marsh Creation Project TE-50, Final report, LDNR, 2006.

2 Goodwin & Associates, Inc. December 2008. Raccoon Island Shoreline Protection/Marsh Creation (TE48) Submerged Cultural Resources Investigations.


5-10

3 C&C Technologies. (C&C) 2003b. New Cut Dune/Marsh Restoration Project Using Ship Shoal Sediment

Coastal Terrebonne Parish, Louisiana: High Resolution Geophysical and Archaeological Survey of the

South Pelto Area Block 13 Vicinity of Ship Shoal.

4 C&C Technologies. (C&C) 2003a. Whiskey Island West Flank Restoration Project Using Ship Shoal

Sediment Coastal Terrebonne Parish, Louisiana: High Resolution Geophysical and Archaeological Survey

of the Portions of Blocks 87, 88, 89, 94, and 95 Ship Shoal Area.

5 Soil Testing Engineers, Inc. (STE) 2004. Sand Source Investigation Ship Shoal - Block 88, Louisiana

Department of Natural Resources Ship Shoal  Whiskey Island West Flank (TE-47) Restoration Project

Terrebonne Parish, Louisiana, LDNR, 2005a.


Figure L5-2. Initial Borrow Area Screening Map


5-12

L5.4 FINAL BORROW AREA SCREENING PROCESS AND RESULTS

The process of screening potential borrow areas continued by reducing them down to

those that provide the requisite volume of sediment, have the geotechnical information,

detailed geophysical survey data, and cultural resources clearance needed to develop

conceptual excavation plans.

The potential borrow areas that were eliminated during this screening were:

Timbalier Island Dune and Marsh Restoration (TE-40) Borrow Area 9e; as shown

on the Khalil and Cantu (2008) map, Figure L5-1. It was eliminated because a

portion of it was landward of the depth of closure and the entire area lacked

cultural resources clearance.

Western Ship Shoal (Blocks 84, 85, 98, & 99), Borrow Area 4 as shown on the

Khalil and Cantu (2008) map, Figure L5-1. It was eliminated because it lacked

detailed geophysical surveys and cultural resources clearance.

HNC Channel. It was eliminated because of the risk and uncertainty of relying on

a sediment source that is under the control of interests with a requirement to

maintain navigability without undue delay, particularly following storm events

that could cause shoaling. The LCA TBBSR Study cannot use the HNC if there is

an emergency. Further, geotechnical and cultural resources data are only

available for the portions of the channel that are periodically maintenance

dredged, not necessarily the channel offshore from Cat Island Pass, the logical

portion to serve as a borrow area because it is seaward of the depth of closure.

There are also restrictions on width of dredge cut, one cannot dredge outside of

the designated channel without an Environmental Assessment, and cut depth, one

cannot dredge deeper than the authorized channel depth. Taken together, these

constraints and restrictions were felt to introduce too much risk to retain the HNC

as a viable borrow area. Because of its location, the PDT Team felt that the HNC

should be retained as an alternative borrow area to be considered in PED if the

cultural resources clearance is obtained and the timing of its use is compatible

with the USACE's navigation interests.

Whiskey Island Back Barrier Marsh Creation (TE-50), Borrow Area 1 as shown

in Figure L5-2. It was eliminated because it lacked geotechnical and borrow area

volume information, detailed geophysical surveys, and cultural resources

clearance.

Whiskey Island Back Barrier Marsh Creation (TE-50), Borrow Area 2 as shown

in Figure L5-2. During the course of planning for the TE-50 project, T. Baker

Smith (TBS) and Moffatt & Nichol (M&N) refined the designs of Borrow Areas 2

and 3, designating one subarea in 2 (2a) and three subareas in 3 (3a, 3b, and 3c).

They recommended use of Subarea 2a. Since the TE-50 project has already

utilized both the overburden and sand resource volumes in Subarea 2a, Borrow

Area 2 was eliminated from further consideration (TBS and M&N, 2007).

The PDT further refined Borrow Area 3. Subareas 3b and 3c were eliminated because

detailed geophysical surveys were not conducted and they lack appropriate clearance.

The Borrow Area 3 outline was reduced to depict only the outline of Subarea 3a.


5-13

In a similar manner, the outline of Area 6, the South Pelto Blocks of Ship Shoal, was

reduced to represent the actual outline of the combined borrow areas identified in Blocks

12 and 13.

Results of the final screening effort are summarized in Table L5-2 and Figure L5-3.

Table L5-2. Final Borrow Area Screening Table

Map

ID Location

Water

Depth,

ft

Sed.

Size,

mm

Type Thickness,

ft

%

Material

Potential

Available

Volume,

mcy

Applicability

Cultural

Resources

Survey

Data

Cultural

Resources

Clearance

Whiskey Island

TE-50 Area 3

(subarea 3a)

16-22 -

Mixed, silt,

clay

(overburden)

3.5-17.4

20%

sand

30.0-

49.7 silt

27.4-

68.7%

clay

7.97 Marsh

1

2006

Chirp,

magnetic,

and side

scan sonar

surveys by

OSI 3

Whiskey Island

TE-50 Area 3

(subarea 3a)

-

0.107

-

0.166

Sand 2.5-14 80%

sand 4.72 Beach/Dune

1

2006

Chirp,

magnetic,

and side

scan sonar

surveys by

OSI

4 New Cut

TE-37 Area 13-16 - Sand 6 - 2.5* Beach/

Dune

vibracore

and

magnetic

surveys

5 Raccoon Island

TE-48 22.5-31 0.09-

0.13

Mixed sand,

silt, clay 10-20

16.5-

24.6%

above

#200

sieve

2.4 Marsh

2 2008

remote

sensing

side scan

and

magnetom

eter

surveys by

Goodwin

BOEMRE

Lease

Pending

(NRCS)

6 South Pelto

blocks 12&13 26-48 0.15-

0.20 Sand 13-20 < 5%

silt 21.3 Beach/

Dune

3 2003

seismic,

sonar, and

magnetic

surveys by

C&C

BOEMRE

Grandfathering

Pending

(CPRA)


5-14

Map

ID Location

Water

Depth,

ft

Sed.

Size,

mm

Type Thickness,

ft

%

Material

Potential

Available

Volume,

mcy

Applicability

Cultural

Resources

Survey

Data

Cultural

Resources

Clearance

Ship Shoal

block 88 17-23 0.19 Sand 10-19 < 5%silt 17.3 Beach/Dune

4 2003

seismic,

sonar, and

magnetic

surveys by

C&C

5 2004

echosound

er and

vibracore

surveys

and

sediment

sampling

analysis

by STE

7

Ship Shoal

blocks

88,89,94,&95

16-32 0.19 Sand 8-12 < 5%

silt 47.5 Beach/Dune

4 2003

seismic,

sonar, and

magnetic

surveys by

C&C

BOEMRE

Grandfathering

Pending

(CPRA)

N/A denotes data not available

* Available volume based upon personal communication with CPRA, August 2009.

 Excludes a volume of 1 mcy estimated for Raccoon Island TE-48 Project.

 Excludes a volume of 7 mcy estimated for Caminada Headland Restoration Project. 1 Ocean Surveys, Inc. (OSI) 2006. Hydrographic, Geophysical and Geotechnical Survey Program Whiskey

Island Back Barrier Marsh Creation Project TE-50, Final report.

2 Goodwin & Associates, Inc. 2008. Raccoon Island Shoreline Protection/Marsh Creation (TE-48)

Submerged Cultural Resources Investigations.

3 C&C Technologies. (C&C) 2003b. New Cut Dune/Marsh Restoration Project Using Ship Shoal Sediment

Coastal Terrebonne Parish, Louisiana: High Resolution Geophysical and Archaeological Survey of the

South Pelto Area Block 13 Vicinity of Ship Shoal.

4 C&C Technologies. (C&C) 2003a. Whiskey Island West Flank Restoration Project Using Ship Shoal

Sediment Coastal Terrebonne Parish, Louisiana: High Resolution Geophysical and Archaeological Survey

of the Portions of Blocks 87, 88, 89, 94, and 95 Ship Shoal Area.

5 Soil Testing Engineers, Inc. (STE) 2004. Sand Source Investigation Ship Shoal - Block 88, Louisiana

Department of Natural Resources Ship Shoal  Whiskey Island West Flank (TE-47) Restoration Project

Terrebonne Parish, Louisiana.


Figure L5-3. Final Borrow Area Screening Map


5-16

L5.5 SCREENED RESTORATION BORROW AREAS

The initially proposed source of borrow sand for beach and dune restoration was Ship

Shoal, an elongate sand body in the Gulf, located 20 to more than 40 miles west of Belle

Pass and four to ten miles south of the Isles Dernieres. It is approximately 31 miles long

and 7 miles wide, lying in a water depth of 9 to 30 ft. Ship Shoal is composed of wellgraded quartz sand (Kulp et al., 2001) and is ideal for use in restoring the Terrebonne

Basin barrier islands, since its grain size is equal to or larger than the sand found on the

islands. Coarser grain sand is more resistant to erosion. Ship Shoal is the nearest,

accessible sand source that contains a sufficient quantity of sand of appropriate quality to

match the native sand found on the islands and achieve the LCA TBBSR goals. Screened

Borrow Areas 6 and 7 depicted in Figure L5-3 are both located on Ship Shoal. Several

closer sand sources, previously identified for other CWPPRA project use, were proffered

to the PDT, and they were investigated. The two most-promising are Subarea 3a of the

Whiskey Island TE-50 Borrow Area 3 and the New Cut TE-37 Borrow Area 4.

The proposed sources of borrow sediments for marsh creation and restoration have also

been identified. Nearshore resources seaward of the depth of closure will be utilized to

provide mixed sediments consisting of fine sand, silts, and clays compatible with the

existing island framework. The two marsh sediment borrow areas are the Raccoon Island

TE-48 Borrow Area 5 and the overburden stratum on Subarea 3a of the Whiskey Island

TE-50 Borrow Area 3.

Conceptual borrow area plans, showing available borings, cultural and infrastructure

avoidance areas, along with typical cross sections were developed based on existing data

and are presented below. The geotechnical and geophysical data for each borrow area are

included in Annex L-1.

L5.6 WHISKEY ISLAND RESTORATION BORROW AREA 3

L5.6.1 Description

Two integrated hydrographic/geophysical surveys and a vibratory coring program were

completed in the GOM in the waters offshore Whiskey Island for the TE-50 project (TBS

and M&N, 2007).

Figures L5-4 and L5-5 present the TE-50 project Borrow Area 3 plan and typical section.

The plan is as developed by TBS (2007), with the south border shifted to accommodate

the requisite offset from the adjacent pipeline.

L5.6.2 Geophysical Analysis

OSI completed the surveys and coring during 2006. The resultant surveys included the

acquisition and analysis of more than 260 statute miles of multi-sensor marine

geophysical data (sounding, seismic/sub bottom Chirp profiling, and magnetometer) in a

LDNR approved search area, encompassing a semi-rectangular area measuring


5-17

approximately 23 square statue miles in size, located on the Gulf-side of Whiskey Island

and depicted as Area 3 in Figure L5-3.

L5.6.3 Geotechnical Analysis

Area 3, an area slightly less than 1 square statute mile in size, was sampled by VC-02,

VC-03, VC-05, VC-06, VC-08 through VC-12, VC-14, VC-15, and VC-41 through VC48. As the largest of all the mapped subareas, it contains the largest quantity of sand

resources. Water depth recorded in Area 3 varies between 16 and 22 ft.

Core and sub bottom data within Area 3 indicate the subsurface sand unit mapped ranges

in thickness from 2.5 to 14.0 ft and is overlain by a varying thickness of overburden,

between 3.5 and 17.4 ft. The subsurface sand identified throughout Area 3 averages

greater than 80% sand by weight with an average grain size between 0.107-0.166 mm.

The percent sand in the overburden sediments, primarily composed of silts/clays,

averages a little more than 20%. Percent silt in the fine component of the overburden

samples, varies from 30.0 to 49.7%, and clay content varies between 27.4 and 68.7% as

reported by OSI in TBS and M&N (2007).

L5.6.4 Volume and Summary

The volumes of overburden sediments and underlying sands estimated for Area 3, less

volume included in the avoidance areas, are approximately 7.97 mcy and 4.72 mcy,

respectively.

Available cultural resources within Area 3 include Chirp sub bottom, magnetometer, and

side scan sonar surveys conducted by ARI in 2006 (OSI, 2006).

Numerical modeling was used to assess the impact that dredging a borrow area will have

on nearshore wave conditions. Four wave conditions selected for evaluation. The

selected wave conditions were developed from previous work and also used in the Ship

Shoal: Whiskey Island West Flank Restoration Study (TE-47) to study the impacts on

wave conditions from dredging the borrow sites (Stone, 2001). Model results (TBS and

M&N, 2007) indicate that dredging Borrow Area 3 to -40 ft NAVD 88 will not produce a

significant change in the wave conditions. Simulated impacts decrease with decreasing

depth, such that they are almost negligible at the -10 ft contour, indicating that impacts to

sediment transport at the nearby barrier shorelines should be minimal.




5-20

L5.7 NEW CUT BORROW AREA 4

L5.7.1 Description

Figure L5-6 presents New Cut Borrow Area 4. This area is an existing active borrow

area previously utilized by LDNR. It is located south of Wine Island in distal deep water

of the HNC Channel alignment. Figure L5-7 presents the New Cut Borrow Area 4

typical section.

L5.7.2 Geophysical Analysis

Seismic surveys have been obtained throughout this area. According to CP&E (2005), a

calibrated seismic trace and the interpolation of reflectors between vibracores depicts a

stratigraphy of good quality sand, shelly sediments, and fine sediments.

L5.7.3 Geotechnical Analysis

The 22 vibracores, taken within the delineated borrow area (Figure L5-6), all indicated

that the surficial deposit was fine sand, varying in thickness from 3.5 to 16.9 ft (mean of

7.8 ft). Beneath that stratum of sand, the deposit consists of successive strata of clay and

sand (CP&E, 2005).

One New Cut cross-sectional diagram (north to south transect) shows a continuous

surficial sand cover (up to 8 ft thick) overlapping coarse-grained shelly layers that thin

out seaward, and layers of fine-grained materials (sand plus clay and clay) that thicken

seawards (CP&E, 2005).

Another New Cut cross-sectional diagram (east-west) presents a continuous surficial sand

layer (up to 10 ft thick) that overlies mixed sediments comprised of alternating layers of

clay, sand plus silt, and sand plus clay. Sand is intermixed with finer-grained materials in

vibracores NCYC-05-02, NCYC-05-03, and NCYC-05-23 (CP&E, 2005).

L5.7.4 Volume and Summary

As shown in Table L5-2, the borrow area was estimated to contain 4.2 mcy of sediment.

A September 2007 CWPPRA project status report indicated that the project was

completed using 850,000 cy of material (sand). Accounting for the cut to fill ratio, the

remaining material, approximately 2.5 mcy (personal communication with CPRA, 2009)

should be available for use as marsh fill, because of its alternating, relatively thin strata of

sand and clay.

Cultural resources and other issues, such as nearshore wave refraction impacts from

mining the sediment have been satisfactorily addressed since this area is an existing,

recently used borrow area, there is no physical evidence of impacts, and the area is

seaward of the depth of closure.




5-23

L5.8 RACCOON ISLAND RESTORATION BORROW AREA 5

L5.8.1 Description

The presence of two buried distributary channels off Raccoon Island was noted by Suter

et al. (1991). During the course of geological investigations for the TE-48 project, a

portion of one buried river channel was located approximately four to six miles south of

Raccoon Island (SJB et al., 2006) on behalf of the Natural Resources Conservation

Service and LDNR. The channel is sublinear, oriented along a northwest/southwest

alignment, with a width ranging from 500 to 750 ft, and at least 20,000 ft in length.

Figures L5-8 and L5-9 present the Raccoon Island Borrow Area 5 plan and typical

section.

L5.8.2 Geophysical Analysis

Geophysical surveys, consisting of sub-bottom, sidescan, bathymetric profiling, and

magnetometer surveying have been conducted in the area offshore of the south coast of

Raccoon Island in Terrebonne Parish, Louisiana. A total of approximately 100 nautical

miles of geophysical survey lines were run (SJB et al., 2006).

L5.8.3 Geotechnical Analysis

A detailed geotechnical investigation consisting of sediment sampling using coring

equipment capable of penetrating and recovering samples to 20 ft below the sea floor

within the primary channel was conducted to determine the sediment characteristics.

Five preliminary short vibracores and thirteen long vibracores were collected during the

project. Laboratory analysis of the sediments indicated the material located within the

northern reach of the primary channel has the most potential for marsh building at

Raccoon Island. The cores taken within the northern reach had an average grain size of

0.10 mm and an average percent coarse fraction retained above the No. 200 sieve of 16.5

%. The texture of the material is mixed sediment with minor sand fractions (SJB et al.,

2006).

L5.8.4 Volume and Summary

By examining the seismic data in concert with core logs and individual grain size

analyses, the geometry, length, width, and depth of a structural basin was developed for

the borrow area plan. The borrow area is approximately 600 ft in width and 10 to 20 ft in

depth, with a range in composite grain size from 0.09 to 0.13 mm.

The borrow area designed for the TE-48 project was 8,850 ft long, from 440 to 890 ft

wide, with a maximum cut depth of 20 ft and an estimated volume of 830,000 cy (NRCS,

2006). The estimated volume of the entire borrow area is approximately 3.0 mcy. The

bottom depth at the north end of the borrow area is -23.5 ft NAVD 88, sloping downward

to -26.5 ft NAVD 88 at the lower end (SJB et al., 2006). Approximately 1.0 mcy are


5-24

expected to be used in the TE-48 project, which yields a remaining potential available

volume of approximately 2.4 mcy.

Wave modeling was performed to evaluate changes to wave refraction and sediment

transport patterns resulting from excavation of the proposed borrow area. Based on the

analysis, it was determined that the proposed borrow area will have minor affects on

wave height, wave refraction and resultant sediment transport patterns in the vicinity of

Raccoon Island. Thus, it is predicted that there will be no adverse impacts on the islands

shoreline (SJB et al., 2006).

Available cultural resources documentation includes remote sensing side scan and

magnetometer surveys conducted in 2008 (Goodwin, 2008). The Natural Resource

Conservation Service (NRCS) has applied for a BOEMRE lease for this borrow area.

The lease is pending.




5-27

L5.9 SOUTH PELTO BORROW AREA 6

L5.9.1 Description

South Pelto Borrow Area 6 lies in Federal waters of the Gulf of Mexico approximately

9.5 miles south of the Isle Dernieres within South Pelto Blocks 12 and 13 (Figure L5-3).

The specific locations designated for dredging on the basis of environmental,

engineering, and archaeological investigations are depicted in Figure L5-10. Figure L5-

11 presents the South Pelto Borrow Area 6 typical sections.

L5.9.2 Geophysical Analysis

Extensive geophysical surveys have been conducted in South Pelto Blocks 12, 13, 14, 18

and 19. Available cultural resources include seismic, sonar, and magnetic surveys

conducted by C&C in 2003 (C&C, 2003b). Based on these surveys, buffers around oil

and gas infrastructures and other magnetic anomalies occurring in and around the

surveyed area were avoided during borrow area design to ensure quality of borrow

sediments and safety of dredging operations and are depicted in Figure L5-10.

Seafloor depths range from 26 to 48 ft NAVD 88 across the surveyed area.

The magnetometer and sidescan sonar surveys for the Ship Shoal borrow areas were

conducted according to BOEMRE guidelines at the time of the survey, which specified

50-meter (164 ft) grid spacing. Numerous sonar targets and magnetometer hits were

recorded. In addition, historical records for pipelines and shipwrecks were acquired and

presented in the appendix of the C&C report. All of this information was incorporated

into an Archaeological and Hazard Map for each borrow area (C&C, 2003b).

L5.9.3 Geotechnical Analysis

Analyses including geotechnical data previously acquired by the Louisiana Geological

Survey and the USGS were presented in a 2003 report covering portions of South Pelto

Blocks 12, 13, 14, 18, and 19, which included high resolution geophysical and

archaeological surveys (C&C, 2003b).

C&C did not collect vibracore samples, however the above-referenced C&C report

presented data from four previously-acquired vibracores from the South Pelto blocks.

One of the South Pelto cores, SS-86-25, had 14.3 ft of sand beneath the surface, followed

by 2.4 ft of lean clay, another 3.6 ft of sand, and then 23.9 ft of clay. The remaining three

cores averaged 5.6 ft of recovery and all of it was sand.

An additional six vibracore samples taken by Coastal Planning & Engineering, Inc.

(Finkl, et al., 2005) to depths of approximately 15 to 20 ft below the sediment surface

have been used to confirm seismic data as part of the analysis.


5-28

Khalil et al. (2007) reported that the South Pelto area contained very clean sand (less than

5% silt in the upper shoal units) in a surficial stratum that ranged in thickness from 13 to

20 ft and generally ranged in grain size from 0.15 to 0.2 mm .

L5.9.4 Volume and Summary

About 21.3 mcy of clean sand is estimated within South Pelto Borrow Area 6. An

archaeological and hazard map, a sand isopach map, and available cultural resources

documentation, including remote sensing side scan and magnetometer surveys, are

included in C&C (2003b).

The wave refraction discussion by Stone et al. (2004) pertains to the South Pelto Blocks

of Ship Shoal. The modeling and monitoring data suggest that excavation of Ship Shoal

in its entirety would not influence the wave climate on the shorelines of the Terrebonne

Basin barrier islands.




5-31

L5.10 SHIP SHOAL BORROW AREA 7

L5.10.1 Description

Ship Shoal Borrow Area 7 is located approximately 10.1 miles south of Whiskey Island

as depicted in Figure L5-3. The hydrographic conditions across most of the borrow site

are relatively flat, with the controlling depths ranging from 17 to 23 ft NAVD 88.

Figures L5-12 and L5-13 present the Ship Shoal Borrow Area 7 plan and typical section.

L5.10.2 Geophysical Analysis

Substantial geophysical surveys were conducted including magnetic anomalies and side

scan sonar contacts (C&C, 2003a). Two areas were recommended for avoidance based on

archaeological potential as depicted in Figure L5-12.

L5.10.3 Geotechnical Analysis

Analyses including geotechnical data previously acquired by the Louisiana Geological

Survey and the USGS were presented in a 2003 report from the EPA covering portions

of Ship Shoal Blocks 87, 88, 89, 94, and 95 (C&C, 2003a).

C&C did not collect vibracore samples; however the above-referenced C&C report

presented data from six previously-acquired vibracores from Ship Shoal. The cores

varied in length: one at 34.8 ft and the remaining five averaged 15.1 ft. The surface

stratum (10.8 ft) of the deepest core was sand, followed by two strata of clay, two of

sand, and ending 9.9 ft into clay. The remaining five cores had from 12.2 to 14.4 ft of

sand below the surface, with only two cores terminating in clay (C&C, 2003a.).

A subsequent geotechnical report for Ship Shoal included sampling data collected by Soil

Testing Engineers (STE, 2004) at Ship Shoal Block 88 to characterize the borrow

material for the TE-47 project. Composite statistics were developed for the upper sand

layer for each vibracore taken within the vibracore sampling area. Thirty-five vibracores

were performed across approximately 730 acres of Block 88 as depicted in Figure L5-12.

The vibracores were spaced at approximately 1100 ft in the east-west direction and 1300

ft in the north-south direction. Detailed boring logs and grain size analysis for each

sample were presented in STE (2004b). The thickness of the upper sand layer is

generally greater than 10 ft over the majority of the sampling area, with some locations

indicating sand to depths of 20 ft. The northeast comer of the sampling area was

observed to contain less sand, with the minimum thickness there observed to be 4 ft. At

the southern edge of the sampling area, two cores showed a minimum thickness of 8 ft.


5-32

L5.10.4 Volume and Summary

The Ship Shoal borrow area covering Blocks 88, 89, 94, and 95 ranges in thickness from

8 to 12 ft and has a mean grain size of 0.19 mm (C&C, 2003a). Assuming the average

thickness of 10 ft, the estimated volume of sand within the Ship Shoal borrow area is

approximately 64.8 mcy. Approximately 17.3 mcy of this volume were estimated by

STE (2004) in an area within Block 88 surveyed for the TE-47 project, which yields a

remaining potential available volume of approximately 47.5 mcy. The TE-47 project has

not received funding, thus this volume was included in the borrow area evaluation.

Available cultural resources include seismic, sonar, and magnetic surveys conducted by

C&C in 2003 (C&C, 2003a).

Stone et al. (2004) used the STWAVE model to examine to the impacts of Ship Shoal

from sediment removal on waves propagation patterns for the range of representative

wave conditions. In a numerical modeling effort, removal of the entire shoal was

simulated and the impact on wave propagation and energy levels discussed suggesting

that shoal removal will not have a significant impact on wave energy conditions along the

Isles Dernieres.




5-35

L5.11 BORROW AREA SUMMARY

Of the fifteen (15) identified potential borrow areas, four (4) were screened out due to

location, i.e., landward of depth of closure, five (5) were screened out due to lack of

detailed geophysical survey data and clearance, and one (1) was screened out because it

had been used for a previous project. Two (2) new ones were added but also screened out

due to insufficient data or lack of clearance, leaving five (5) potential borrow areas. Of

the five (5), three (3) contain beach compatible sand for beach and dune restoration,

totaling over 71 mcy; two (2) contain mixed sediments compatible for marsh creation,

totaling 10.37 mcy; and one (1) contains a layer of marsh material above a layer of

beach/dune material, totaling 7.97 and 4.72 mcy, respectively.

L5.12 BACK-BARRIER ANALYSES

Back-barrier geotechnical investigations and analyses were performed to determine

design criteria in support of the CWPPRA TE-48 project on Raccoon Island (NRCS,

2007) and the CWPPRA TE-50 project on Whiskey Island (LDNR, 2007). The extent of

the investigations and analyses included the drilling of soil test borings to determine

subsoil conditions and stratification, and to obtain samples of the various substrata. Soil

mechanics laboratory tests, performed on samples obtained from the borings, were used

to evaluate the physical properties of the subsoils. Engineering analyses, based on the soil

borings and laboratory test results, were made to evaluate the stability of the foundation

support for the proposed shoreline protection and marsh creation features. Analyses were

performed to evaluate stability of the containment dike and retained marsh fill. Analyses

were also made to estimate settlement of the dike and marsh area fill and the time-rate of

settlement of these features.

Soil mechanics laboratory tests consisting of natural water content; unit weight;

unconfined compression; and unconsolidated, un-drained compression were performed

on undisturbed samples obtained from the soil test borings. Tests were performed on

selected samples to classify the soils such as liquid limit, plastic limit, and plasticity

index. Consolidation tests were performed on selected samples to determine their

compressibility and stress history. Grain size analyses were performed on selected

samples to determine their particle distribution curves.

The results of the laboratory analyses were applied to determine the time-rates of

consolidation settlement for the containment dike and marsh fill designs. The time-rate

calculations accounted for the foundation settlement of the subsoils due to the weight of

the fill, and self-weight consolidation within the imported fill materials themselves.

Settlement curves were developed for various dike and marsh platform elevations in

varying bay bottom depths under varying water depths. It is noted that geologic

subsidence needs to be factored in to compute the time-rates of total effective settlement.

It was observed that fairly rapid settlement caused by the weight of the dike and the

influence of the recently placed fill along with self-weight consolidation occurs within

the first one to two years following construction. Following the initial two years, a

steadier settling takes place which is dominated by the fairly constant geologic

subsidence.


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On Raccoon Island, design criteria for the breakwaters including bearing capacity,

stability, and settlement were also developed.

These detailed analyses served as the design criteria for the island restoration measures

described in Section L6.


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L6. RESTORATION DESIGN PLANS

L6.1 GOAL STATEMENT

The LCA TBBSR Study was identified in the 2004 LCA Plan (USACE, 2004) and was

recommended to the Congress in the Chief of Engineers report, dated January 31, 2005

(USACE, 2005). The report recommended a coordinated, feasible solution to the

identified critical water resource problems and opportunities in Coastal Louisiana. The

LCA TBBSR was included as one of the critical near-term restoration features throughout

Coastal Louisiana. Title VII of the WRDA of 2007 authorizes the LCA program.

The Study goal defined in the 2004 LCA Plan and WRDA 2007 is to restore the

geomorphologic form and ecologic function of the Terrebonne Basin barrier islands

through simulating historical conditions by enlarging the barrier islands (width and dune

crest) and reducing the current number of breaches.

L6.2 BARRIER ISLAND GEOMORPHOLOGIC FORM AND ECOLOGIC FUNCTION

The barrier islands in the Study Area are the remains of an abandoned Mississippi River

Delta; and their degradation is the result of anthropogenic activities and episodic storm

impacts, in combination with natural deltaic processes. The barrier islands are typically

low lying and comprised of three physical features, the beach, dune, and back barrier

marsh. They act as a buffer to reduce the full force and effects of wave action, saltwater

intrusion, storm surge, and tidal currents on associated estuaries and wetlands. To restore

their geomorphologic form and provide this buffer involves reinforcing the shoreline

through beach and dune restoration. In addition, it includes providing a marsh platform

to capture overwash sediments during episodic events; sediment that would otherwise be

carried into back bay areas to form shoals or be lost into deeper waters. The marsh also

serves as a roll over platform as the islands migrate landward.

Restoration of ecologic function of the barrier islands includes vegetating both the

restored dunes and back barrier marsh platforms with native plants, to provide wetland

habitat for a diverse number of plant and animal species and to help retain sediment.

This approach is supported by the Wetland Value Assessment (WVA) methodology,

which has been chosen as the model to evaluate the ecosystem restoration project

benefits. The WVA methodology states that the key habitat components, dune, supratidal

(beach), and intertidal (marsh), combine to provide the optimum metric by which the

islands should be compared (CWPPRA, 2002). Below are the WVA model elevations

that define dune, beach, and marsh:

Dune elevation 5 ft NAVD 88;

2 ft NAVD 88  beach elevation  4.9 ft NAVD 88;

0.0 ft NAVD 88  marsh elevation  1.9 ft NAVD 88.

The marsh habitat has the highest weighting in the analysis used to compute the benefits,

due to its ecologic function. The WVA criterion is to provide intertidal habitat for the


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longest duration physically practicable within the period of analysis, as determined by

computing Average Annual Habitat Units.

L6.3 PLAN FORMULATION SUMMARY

L6.3.1 Introduction

The plan formulation process including the descriptions of the measures and the

justification for selecting or rationale for screening each measure is summarized below

and detailed in the Integrated Feasibility Study and Final Environmental Impact Statement

Report, Section 3 Alternatives. The process included development of a range of hardstructural and soft-structural measures to address the specific problems, needs, and

objectives of the Study and achieve the goal of restoring the geomorphologic form and

ecologic function of the seven barrier islands within the Terrebonne Basin. The following

steps were employed by the PDT in the process:

Identify a wide range structural measures;

Perform initial screening;

Perform second level screening;

Perform final screening;

Create structural designs; and

Compute construction component quantities.

L6.3.2 Summary of Measures

A wide variety of hard-structural and soft-structural measures was considered in the

initial step including breakwaters, revetments, groins, terminal groins, sand fencing,

barges/ships, sheet pile, pass closure, canal plugs, dune restoration, marsh creation, beach

restoration, beach nourishment, subtidal sediment placement, addition of sediment into

near-shore environment to supplement littoral drift, breach closure, small march island

construction on bayside for bird habitat, vegetation planting, herbivore control, bioengineered oyster reefs, spit creation, and canal backfilling.

L6.3.3 Initial Screening

The initial screening criteria were agreed upon by the PDT. The identified measures

were selected and screened based upon experience with previous restoration efforts in the

Study Area, knowledge of the Study Area, conventional scientific theory, best

professional judgment, and consideration of the Study objectives.

Management measures were first screened based on their ability to meet the following

five criteria:

Consistency with Authorization and Purpose - measure is fully consistent with

Project authorization and purpose;

Achievement of Planning Objectives - measure is fully supportive of planning

objective(s);


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Efficiency - measure directly influences the area(s) of greatest need;

Environmental Impacts - measure presents no readily apparent potential for

adverse environmental impacts; and

Engineering Feasibility - measure directly supported by acceptable engineering

and industry practices/physical plant.

Table L6-1 presents initial screening results by management measure.

Table L6-1. Initial Screening Results by Management Measure

Measure Code Management Measure Carried Forward?

(Yes/No)

Hard-Structural

HSM1 - Segmented Breakwaters (Specific Location) Yes

HSM2 - Continuous Breakwaters (Specific Location) No

HSM3 - Segmented Breakwaters (Entire Island) No

HSM4 - Continuous Breakwaters (Entire Island) No

HSM5 - Segmented Revetments (Specific Location) No

HSM6 - Continuous Revetment (Specific Location) Yes (Wine Island Only)*

HSM7 - Segmented Revetments (Entire Island) No

HSM8 - Continuous Revetment (Entire Island) No

HSM9 - Terminal Groins Yes

HSM10 - Groins No

HSM11 - Sand fencing Yes

HSM12 - Sunken Barges/ships No

HSM13 - Floating Barges/ships No

HSM14 - Segmented Sheet pile (Specific Location) No

HSM15 - Continuous Sheet pile (Specific Location) No

HSM16 - Segmented Sheet pile (Entire Island) No

HSM17 - Continuous Sheet pile (Entire Island) No

HSM18 - Pass Closures No

HSM19 - Canal Plugs Yes

Soft-Structural

SSM1 - Dune Restoration Yes

SSM2 - Marsh Creation Yes

SSM3 - Beach Restoration Yes

SSM4 - Subtidal Sediment Placement Yes

SSM5 - Addition of Sediment into Nearshore Environment Yes

SSM6 - Breach Closure Yes

SSM7 - Small Marsh Island Construction on Bayside Yes

SSM8 - Vegetation Planting Yes

SSM9 - Herbivory Control (Backbarrier Marsh) Yes

SSM10 - Bio-engineered Oyster Reefs No

SSM11 - Spit Creation (E&T Habitat) Yes

SSM12 - Backfilling Canals Yes

TOTAL MEASURES CARRIED FORWARD 16

HSM Denotes Hard-structural Measure, SSM Denotes Soft-structural Measure

*Continuous revetments placed at specific locations were eliminated because of potential environmental

impacts with the exception of Wine Island. Wine Island is unique in that it was once surrounded by a

boulder revetment to hold discharged material from dredging the HNC. The island is no longer contained

within the revetment.


6-4

L6.3.4 Second Level Screening

The initial screening effort evaluated the measures as they applied to the Terrebonne

Basin barrier island system in its totality, as a unit or system. The second level process

built on the initial screening, with emphasis on individual measures as they would apply

to each island in the system. This screening process was undertaken during a three-day

field trip to the islands (July 27-30, 2009), involving 20 members of the PDT,

representing the responsible State and Federal agencies and their consultants. Results of

the previous screenings were reviewed in situ, along with observations of the conditions

of past CWPPRA and Coastal Impact Assistance Program (CIAP) projects. The days

observations were reviewed, reinforced, and recapitulated during evening discussions, to

ensure this consensus. Based on these discussions, it was determined that no stand-alone

measure would achieve project objectives. Furthermore, it was the consensus of the PDT

that the primary island strategy should be a combination of beach, dune, and marsh

restoration measures. These measures, when used in combination, were the only

management measures capable of meeting the primary objective of restoring the

geomorphologic form and ecologic function of the barrier islands. Table L6-2 presents

second level screening results by individual island.

Table L6-2. Second Level Screening Results by Island

Island Management Measure Code*

Raccoon HSM1, HSM5, HSM9, HSM11, SSM1 through SSM12

Whiskey HSM1, HSM5, HSM9, HSM11, SSM1 through SSM12

Trinity HSM1, HSM5, HSM9, HSM11, HSM19, SSM1 through SSM12

East HSM1, HSM5, HSM9, HSM11, SSM1 through SSM12

Wine HSM6, HSM8, SSM2, SSM8, SSM9

Timbalier HSM1, HSM5, HSM9, HSM11, SSM1 through SSM12

East Timbalier HSM9, HSM11, SSM1 through SSM12

* see Table L6-1 for code descriptions

L6.3.5 Final Screening

At this point in the screening process, the PDT had concluded that the island strategies

must include a beach, dune, and marsh component in order to achieve the objectives of

the project. Therefore, the final screening effort, which built upon the second level

screening process, evaluated the use of supplementary measures including sand fences,

vegetative planning, herbivory control, breakwaters, terminal groins, and continuous

revetments (for Wine Island Only). Table L6-3 presents final screening results by

individual island.


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Table L6-3. Final Screening Results by Island

Island Management Measure Code*

Raccoon HSM1, HSM9, and combination of SSM1, SSM2, SSM3, SSM8, and

HSM11

Whiskey HSM1 and combination of SSM1, SSM2, SSM3, SSM8, and HSM11

Trinity Combination of SSM1, SSM2, SSM3, SSM8, and HSM11

East Combination of SSM1, SSM2, SSM3, SSM8, and HSM11

Wine HSM8 (repair of existing) and combination of SSM1, SSM2, SSM3,

SSM8 and HSM11

Timbalier SSM6, SSM12, and combination of SSM1, SSM2, SSM3, and HSM11

East Timbalier SSM12, and combination of SSM1, SSM2, SSM3, and HSM11

* see Table L6-1 for code descriptions

L6.3.6 No Action Plan (Plan A)

The No-Action Plan, denoted as Plan A, is fully described in the Integrated Feasibility

Study and Final Environmental Impact Statement Report, Section 3.4.1. Plan A serves as

the basis of comparison for the Future Without Project (FWOP) conditions scenario. The

FWOP conditions were compared to the proposed restoration measures, that is, Future

With Project (FWP) conditions, in the plan formulation process to determine the net

habitat benefits from construction.

L6.4 RESTORATION DESIGN STEPS

The design process included development of a range of restoration plans to enable the

determination of the minimized restoration templates for each component. The following

steps were used in the process:

Determine historic erosion rates for each island;

Determine design relative sea level change;

Estimate fill compaction component for each island;

Determine design storm events and storm-induced erosion;

Calculate design acreage component for each island;

Evaluate and, if applicable, account for existing CWPPRA and other related

project plans;

Create design fill templates for each island; and

Compute design fill volumes and related construction component quantities.

L6.5 BARRIER ISLAND COMPONENTS

L6.5.1 Definition

The PDT defined the minimized restoration design template, denoted as Plan B, as the

construction of the minimal barrier island dimensions that restore the barrier islands


6-6

geomorphic form and ecologic function and retains this form and function after being

subjected to the design storm events. The design storm events chosen included a

hypothetical 50-year design storm, and historic storms, Hurricanes Katrina and Rita,

which occurred in 2005, and Hurricanes Gustav and Ike, which occurred in 2008, as

required by USACE guidance developed from recommendations initiated by the

Interagency Performance Evaluation Task Force on Hurricane Katrina.

L6.5.2 Beach and Dune

Annex L-3 presents SBEACH (Storm-induced BEAch CHange) model simulations that

were performed on an array of various restoration templates. The widths were increased /

decreased by increments of 25 ft and elevations were increased or decreased by

increments of 0.1 ft in order to derive the appropriate combination of beach berm and

dune template superimposed on the beach berm. Based on the results of these

simulations, the following minimal beach and dune island dimensions were derived for

the Plan B design to meet the restoration template definition:

Ggulf-side beach width = 250 ft;

Beach elevation = 3.8 ft NAVD 88;

Dune width = 100 ft;

Dune elevation = 6.0 ft NAVD 88; and

Bay-side beach width = 100 ft.

L6.5.3 Marsh

The marsh serves as a roll over platform as the islands migrate landward. Based on the

post-storm observations from the recent historic storms, there is ample evidence that the

back-barrier marsh width needs to be on the order of 1,000 ft to capture overwash

sediments during episodic events; sediment that would otherwise be carried into back bay

areas to form shoals or be lost into deeper waters. Cross-shore sediment transport

models, e.g., SBEACH, tend to underestimate the extent of overwash; therefore a

literature review was conducted to support the design criteria for the width of the marsh

platform. Examination of vertical aerial photographs of the Texas coast, made following

Hurricane Ike, show areas of overwash extending from 800 to 1,300 ft inland (Ewing,

2009). An extensive study of overwash on the Caminada-Moreau Headland by Ritchie

and Penland found that, for much of the low shoreline, overwash penetrated from 700 to

more than 1,000 ft beyond the beach (Ritchie and Penland, 1989). Examination of the

aerial photographs in Williams, et al. (1992) show overwash areas extending to 1,300 ft

on Timbalier Island and greater than 700 ft on East Island. Personal observations by

various PDT members support planning for a minimum marsh width of 1,000 ft.

Therefore, 1,000 ft was defined as the minimal marsh platform width for the Plan B

design to meet the restoration template definition.

Based on similar Louisiana barrier island restoration plans, the average healthy marsh

elevation, defined as the target elevation for the marsh platform, is typically within +/-

0.1 ft of MHW. MHW for the Study Area is approximately 1.6 ft NAVD 88 and was


6-7

defined as the minimal marsh platform target elevation for the Plan B design to meet the

restoration template definition.

L6.6 DESIGN CRITERIA (PLAN B)

L6.6.1 Bathymetric/Topographic Data

The island profiles used in the development of the design templates were produced from

the BICM survey data set acquired in 2006 as described in Section L3. The survey data

were utilized to develop representative profiles for each island. These profiles were also

used in the SBEACH simulations described in Annex L-3 and served as the basis for

calculating fill volumes required for the restoration design plans.

L6.6.2 Long-Term Erosion Rates

Because construction commencement is planned for 2012, designated as Target Year

Zero (TY0), the designs had to account for erosion that would occur between 2006 and

2012. Design long-term erosion rates developed in Section L3.2 were used to calculate

each barrier islands recession rate over the 6-year period. Fill templates were shifted

landward of the 2006 shoreline positions to account for the projected erosion of the

barrier shoreline by 2012.

L6.6.3 Relative Sea Level Change

Relative sea level change analysis was performed in accordance with the EC 1165-2-211

18-step guidance developed by USACE and presented in Section L2.7. According to this

guidance, future subsidence rate remains constant, however, future eustatic SLR rate has

three trends: historic (constant), intermediate (increase), and high (increase).

Based on the analysis, relative SLR derived from the intermediate trend (NRC Curve I)

between 2006 and 2012 is equal to 0.2 ft. Therefore, the minimized restoration template

design elevations were adjusted by a 0.2-ft vertical shift.

As demonstrated by the comparative analysis of the historic erosion rates adopted for the

study and relative SLR induced erosion rates expressed in terms of the Bruun Rule

(Sections L2.7 and L3.3), the uncertainties associated with future SLR and land loss

subsidence are more than accounted for.

L6.6.4 Fill Compaction

The minimized restoration template was then analyzed to determine whether the

beach/dune and marsh would require a vertical adjustment to account for compaction

defined herein as the combined foundation settlement of the subsoils due to the weight of

the fill and the self-weight consolidation within the imported fill materials themselves.

The compaction value is a function of fill thickness and was derived for each island

individually. The relationship between the fill thickness and compaction was developed


6-8

based on data obtained from the CWPPRA project designs for Whiskey Island (LDNR,

2007) and Raccoon Island (NRCS, 2007) as described in Section L5.12.

Because the minimized templates beach/dune fill was sited above the mean low water

line (MLW), the compaction value for the beach/dune portion of the fill was negligible.

For Raccoon Island, the average beach/dune fill thickness below MLW was 2.2 ft,

resultant compaction value was 0.2 ft, and its minimized restoration template design

beach/dune elevations were shifted vertically accordingly.

Table L6-4 presents the average marsh fill thickness below MLW and the corresponding

compaction value for each island. Based on the compaction analysis results, the

minimized restoration template design marsh platform elevations were shifted vertically

according to the compaction values.

Table L6-4. Marsh Thickness and Compaction Values

Island Raccoon Whiskey Trinity East Wine Timbalier East

Timbalier

Average Thickness

(ft) 6.8 2.9 4.6 4.6 3.1 3.6 5.3

Compaction (ft) 0.7 0.3 0.5 0.5 0.3 0.4 0.5

L6.6.5 Existing CWPPRA Projects

The beach/dune and marsh design templates were reduced/adjusted to account for the

CWPPRA TE-48 project on Raccoon Island (NRCS, 2007) and the CWPPRA TE-50

project on Whiskey Island (LDNR, 2007).

L6.6.6 Summary

Table L6-5 presents the summary of the dimensions of the TY0 (2012) Plan B restoration

templates for each island. The restoration design plans and representative cross sections

are presented in Annex L-2.

Table L6-5. Summary of TY0 Minimized Template Dimensions (Plan B)

Island Raccoon Whiskey Trinity East Wine Timbalier East

Timbalier

Gulf-side Beach

Width (ft) 250 250 250 250 250 250 250

Dune Width (ft) 100 100 100 100 100 100 100

Bay-side Beach

Width (ft) 100 100 100 100 100 100 100

Marsh Width (ft) 1,000 1,000 1,000 1,000 1,000 1,000 1,000

Beach Elev.

(ft, NAVD 88) 4.2 4.0 4.0 4.0 4.0 4.0 4.0

Dune Elev.

(ft, NAVD 88) 6.4 6.2 6.2 6.2 6.2 6.2 6.2

Marsh Elev.

(ft, NAVD 88) 2.5 2.1 2.3 2.3 2.1 2.2 2.3


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L6.7 RESTORATION DESIGNS FOR VARIOUS DESIGN PERIODS (PLANS C, D

AND E)

L6.7.1 Design Definition

In order to evaluate extending the longevity of the habitats created through the minimized

restoration plan concept and enabling scaling, the PDT developed restoration plans for

specific design periods. The definition of each plan was to ensure that the minimum

restoration acreage would be retained at the end of the specified period. The PDT

selected the 5-year (Plan C), 10-year (Plan D), and 25-year (Plan E) design periods,

which were considered sufficient for developing a range of values for alternative plan

formulation. The 50-year design period was screened out by the PDT because, in order

to sustain itself for 50 years, the marsh platform would have to be elevated so high that it

would not function as a marsh for the majority of the 50-year period of analysis. The

marsh platform would not compact or subside to yield intertidal habitat for decades, thus

this barrier island restoration template did not meet the definition of restoring

geomorphologic form and ecologic function and was eliminated from further

consideration.

L6.7.2 Design Components

L6.7.2.1 Long-Term Erosion Rates

Building upon the minimized restoration plans presented in Table L6-5 and long-term

erosion rates developed in Section L3.2, the gulf-side beach width was increased for each

island to account for design losses equivalent to the corresponding design period. For

example, to create the Raccoon Island 10-year restoration plan, the Raccoon Island

minimized gulf-side beach was extended landward by 28.6 ft/yr * 10 yrs = 286 ft. This

typically resulted in the restoration template extending over existing island framework

covering vegetated areas in both existing dunes and marsh.

L6.7.2.2 Design Storm Events

Using the results of the SBEACH modeling presented in Annex L-3, the beach width was

increased for each island to account for the predicted value of shoreline recession in

response to the specified design period storm event. The predicted values for the 5-year,

10-year, and 25-year design storms were 25 ft, 52 ft, and 77 ft, respectively. For example,

for the Raccoon Island Plan D, in addition to the 286 ft of beach discussed in previous

section, the Raccoon Island minimized gulf-side beach was extended further landward by

52 ft for a total of 338 ft.


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L6.7.2.3 Short-Term Land Loss Rates

Building upon the minimized restoration templates, the marsh width was increased for

each island to account for design marsh losses equivalent to the corresponding design

period. The design short-term marsh land loss rates were developed in Section L3.3 based

on the BICM (LDNR, 2008) and USGS (USGS, 2006) data sets and are summarized in

Table L6-6.

Table L6-6. Short-Term Marsh Loss Rates

Island Raccoon Whiskey Trinity/East Timbalier East

Timbalier

Marsh Loss

Rate (ac/yr) 8.4 14.4 3.1 10.9 23.8

For example, for the Raccoon Island Plan D, the Raccoon Island minimized marsh was

extended landward by 84 acres which is equivalent to an average additional width of

approximately 340 ft added on the bay side.

L6.7.2.4 Relative Sea Level Change

Relative sea level change analysis was performed in accordance with the EC 1165-2-211

18-step guidance developed by USACE and presented in Section L2.7. According to this

guidance, future subsidence rate remains constant, however, future eustatic SLR rate has

three trends: historic (constant), intermediate (increase), and high (increase).

Based on the analysis, relative SLR derived from the intermediate trend (NRC Curve I)

between 2012 and 2017 is equal to 0.2 ft. Between 2012 and 2022, the SLR is equal to

0.4 ft and between 2012 and 2037 it is 0.9 ft. Therefore, the minimized restoration

template design elevations were adjusted by a 0.2-ft, 0.4-ft and 0.9-ft vertical shifts for

Plans C, D, and E, respectively..

As demonstrated by the comparative analysis of the historic erosion rates adopted for the

study and relative SLR-induced erosion rates expressed in terms of the Bruun Rule

(Sections L2.7 and L3.3), the uncertainties associated with future SLR and land loss

subsidence are more than accounted for.

L6.7.2.5 Existing CWPPRA Projects

For Plans C and D, the beach/dune and marsh design templates were reduced/adjusted to

account for the CWPPRA TE-48 project on Raccoon Island (NRCS, 2007) and the

CWPPRA TE-50 project on Whiskey Island (LDNR, 2007). However, Plan E

encompasses the footprints of these two projects because the CWPPRA projects overall

subsidence and settlement results in significant loss of geomorphologic form and

ecologic function prior to TY25.


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L6.8 HARD-STRUCTURAL MEASURE DESIGNS

L6.8.1 Hard-Structural Design Parameters

L6.8.1.1 Raccoon Island  Additional Breakwaters

As part of the TE-29 project, eight detached segmented breakwaters were constructed in

1997 at the eastern end of Raccoon Island to reduce shoreline erosion and promote

accretion. These breakwaters are widely regarded as having fulfilled their intended

function due to rapid salient development behind most of the breakwaters and a

measurable decrease in the rate of shoreline retreat. In 2005, eight additional breakwaters

were constructed immediately west of the original eight structures (TE-48 project).

Based on the performance of the TE-29 and TE-48 breakwaters and their parameters, a

hard-structural design plan was developed, consisting of eight 300-ft long detached

breakwaters spaced 300 ft apart along the remaining western part of Raccoon Island, in

combination with placing beach, dune, and marsh fill. This structural measure was

designed and evaluated based on the results of GENESIS modeling simulations of the

existing breakwaters (Annex L-3) and their positive influence on the Raccoon Island

shoreline. The modeling results yielded a negligible background erosion rate in the lee of

the structures. The SBEACH modeling results were then used to predict the magnitude of

shoreline erosion from episodic events within each design period to assess the

performance of the breakwaters on the evolution of habitat acres over time. A 20-year

design life was selected by the PDT based on the design criteria for compaction (Section

L5.12) and relative SLR change. A typical design plan and section for the breakwaters

are included with the restoration design plans in Annex L-2.

L6.8.1.2 Raccoon Island  Terminal Groin

This hard-structural design plan was aimed at capturing the net longshore sediment

transport by constructing a 1,200-ft long terminal groin at the western end of Raccoon

Island in combination with placing beach, dune, and marsh fill. This would result in

retaining sediment on the beach updrift of the groin. This structural measure was

evaluated by GENESIS modeling simulations (Annex L-3). The modeling results

provided the background erosion rate used to assess the performance of the structure on

the evolution of habitat acres over time. A 20-year design life was selected by the PDT

based on the design criteria for compaction and relative SLR change. A typical design

plan and section for the breakwaters are included with the restoration design plans in

Annex L-2.

L6.8.1.3 Whiskey Island  Breakwaters

The design parameters for the breakwaters on Whiskey Island were based on the

structural configuration of the TE-29 breakwaters on Raccoon Island. This hard-structural

design plan consisted of constructing 300-ft long detached breakwaters spaced 300 ft

apart along the entire length of Whiskey Island 300 ft gulfward of the shoreline, in

combination with placing beach, dune, and marsh fill. The modeling results provided the


6-12

background erosion rate used to assess the performance of the structure on the evolution

of habitat acres over time. A 20-year design life was selected by the PDT based on the

design criteria for compaction and relative SLR change. A typical design plan and section

for the breakwaters are included with the restoration design plans in Annex L-2.

L6.8.2 Operation & Maintenance Measures

L6.8.2.1 Breakwaters and Terminal Groin

The purpose of Operation and Maintenance (O&M) is to allow a project to continue to

function. For a structure such as a breakwater or a terminal groin, O&M is required to

keep the structure functioning at a certain level to provide the benefits claimed in the

analysis.

The breakwaters and terminal groin structural measures were evaluated based on a design

life of 20 years. During this time, the structures will be maintained and repaired, if

necessary. Based on information obtained through personal communication with NRCS,

one of the sixteen TE-29 and TE-48 breakwaters on Raccoon Island had to be repaired

because of structural settlement (Personal communication, Loland Broussard of NRCS,

Dec, 02, 2009). Otherwise the existing breakwaters have performed and required little to

no O&M. Costs for O&M are projected for the applicable measure and discussed in

Section L9.

After 20 years, the effectiveness of the structural measures is projected to substantially

diminish because of the sea level change, subsidence, and barrier island landward

migration. Maintenance of the structures to the original design after 20 years will no

longer result in the same level of function and benefits as the original structures once

provided. In order to make the breakwaters and terminal groin functioning and beneficial

after 20 years, the structures will have to be modified and rebuilt, which does not qualify

as O&M.

L6.9 PROTECTION OF EXISTING HABITATS

As described in the design process, the templates for the conceptual design plans placed

the fill over existing healthy vegetated habitats. During a field trip to the Study Area

conducted in July 2009, concerns were expressed by various PDT members as they

observed that existing healthy vegetated dunes and marsh areas would be covered by the

proposed restoration plans on the majority of the seven islands as well as existing healthy

mangroves on Raccoon and Whiskey Islands. These concerns were discussed through the

plan formulation process and it was determined by the PDT that dune and marsh habitats

could be recreated as part of the restoration plans. However, due to the challenges with

recreating existing mangrove habitats, the PDT determined that covering existing healthy

mangrove habitats was inconsistent with the Study goals and objectives, thus the fill

templates for Raccoon and Whiskey Islands were redesigned by translating the beach and

dune gulfward noting these plans increased the volume of sand required to achieve the

design templates.


6-13

L6.10 HABITAT ACREAGES

The cross-shore forcing functions including storm impacts, overwash, island rollover and

migration northward combined with the affects of relative SLR dominate the erosion

processes on the islands compared to the alongshore forcing functions. Therefore, the

historic shoreline change rates and land loss rates combined with the affects of relative

SLR served as the design criteria for background erosion and determining habitat

evolution over time versus the sediment budget.

Table L6-7 presents existing habitat acres (Plan A) and the habitat acres created by each

restoration plan (Plans B, C, D, and E) based on the intermediate SLR trend (NRC Curve

I). The total acres at key target years within the 50-year period of analysis were

determined by applying the design criteria for shoreline erosion, compaction, relative

SLR, land loss, and storm erosion. The weighted average was computed by taking the

values at each key target year, averaging them, and then multiplying by the period. This

process is fully described in Appendix K.

Table L6-7. Summary of Created Habitat Acres

Island Plan

Beach/Dune

Area at TY1*

(ac)

Marsh

Area at

TY1

(ac)

Total

Area at

TY1

(ac)

Total Area

at TY50

(ac)

Weighted

Average

Area over

50 years

(ac)

Plan A 51 184 235 0 77

Plan B 271 235 506 23 343

Plan C 341 237 578 227 428

Plan D 520 122 642 292 490

Plan E 751 39 790 476 637

Plan B w/ BW 271 237 508 38 368

Plan C w/ BW 342 239 580 276 457

Plan D w/ BW 521 122 643 341 521

Plan E w/ BW 752 39 791 540 671

Plan B w/ TG 271 237 508 34 364

Plan C w/ TG 341 238 579 270 453

Plan D w/ TG 520 122 642 337 515

Raccoon

Plan E w/ TG 751 38 789 534 666

Plan A 377 443 820 0 290

Plan B 670 509 1180 276 691

Plan C 895 377 1271 363 801

Whiskey

Plan D 986 376 1362 355 869

Plan E 1402 250 1652 475 1163

Plan A 238 326 564 0 131

Plan B 464 569 1033 33 553

Plan C 585 564 1149 199 667

Trinity

Plan D 1198 72 1270 298 789

Plan E 1523 67 1589 625 1114


6-14

Island Plan

Beach/Dune

Area at TY1*

(ac)

Marsh

Area at

TY1

(ac)

Total

Area at

TY1

(ac)

Total Area

at TY50

(ac)

Weighted

Average

Area over

50 years

(ac)

Plan A 199 59 258 0 68

Plan B 318 362 680 46 359

Plan C 385 372 756 122 432

Plan D 802 33 835 192 512

East

Plan E 1027 33 1060 397 733

Plan A 5 6 11 0 4

Plan B 109 97 206 5 131

Plan C 122 117 239 9 161

Plan D 130 140 270 7 188

Plan E 349 17 366 229 298

Wine

Ring Only 26 3 29 1 8

Plan A 606 374 979 2 341

Plan B 903 726 1629 175 890

Plan C 1743 85 1828 373 1095

Plan D 1952 83 2035 571 1304

Timbalier

Plan E 2561 69 2630 1141 1898

Plan A 75 133 208 4 87

Plan B 376 452 828 7 538

Plan C 1057 71 1128 496 765

Plan D 1170 60 1230 726 983

East

Timbalier

Plan E 1762 99 1861 1310 1576

* TY1 denotes Target Year 1 when construction is completed

L6.11 National Ecosystem Restoration (NER) Plan

The USACE objective in ecosystem restoration planning is to contribute to National

Ecosystem Restoration (NER) Plan. Contributions to national ecosystem restoration

(NER outputs) are increases in the net quantity and/or quality of desired ecosystem

resources. Measurement of the NER Plan is based on changes in ecological resource

quality as a function of improvement of habitat quality and/or quantity and expressed

quantitatively in physical units or indexes (ER 1105-2-100).

As identified through three levels of screening, the measures carried forward into the

alternatives development stage included at a minimum dune restoration, marsh creation,

and beach restoration. During the plan formulation PDT meetings, the NER Plan was

defined as the most cost effective plan that yielded the optimal habitat benefits from

restoring the geomorphologic form and ecologic function of the beach, dune and marsh

components on one or more of the islands.

Raccoon with Terminal Groin (Plan E) / Whiskey (Plan C) / Trinity (Plan C) / and

Timbalier (Plan E) with the addition of renourishment was selected as the NER Plan The

alternative restores the geomorphologic form and ecologic function of the four islands in

the Terrebonne Basin barrier island system. Immediately after construction (TY1), the


6-15

NER Plan will add 3,283 acres of habitat (dune, intertidal, and supratidal) to the existing

island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing the

total size of the islands to 5,840 acres.

The renourishment quantity and sequencing was selected by determining the minimum

amount needed to maintain the geomorphic form and ecologic function of the islands

throughout the 50-year period of analysis (Appendix K). The resulting configurations are

provided in Table L6-8. Marsh renourishment was not included since the initial

restoration plan provides for significant intertidal habitat throughout the 50-year period of

analysis.

Table L6-8. Renourishment Sequencing and Plans

Island Plan Renourishment Year Renourishment Plan

Raccoon Plan E w/ TG TY30 Restore Plan B

TY20 Add Plan C Whiskey Plan C * TY40 Add Plan B

Trinity Plan C TY25 Add Plan C

Timbalier Plan E TY30 Restore Plan B

* Whiskey would require two renourishments, one at TY20 and one at TY40

Raccoon Plan E will be renourished at TY30 by adding adequate sediment such that the

dune and supratidal beach acres would be equivalent to that of a newly constructed Plan

B template (i.e. restore a Plan B at TY30). No additional marsh material will be added.

Whiskey Plan C will require two renourishment intervals. The first will occur at TY20

and will include the addition of the same amount of dune and supratidal beach habitat

that was originally created in TY1 (i.e. add a Plan C to the template at TY20). The

second renourishment interval will occur at TY40 and will include the addition of the

same amount of dune and supratidal beach habitat needed to construct a Plan B template.

No additional marsh material will be added.

Trinity Plan C will be renourished at TY25 by adding the same amount of dune and

supratidal beach habitat that was originally added in TY1 (i.e. add a Plan C to the

template at TY20). No additional marsh material will be added.

Timbalier Plan E will be renourished at TY30 by adding adequate sediment such that the

dune and supratidal beach habitat acres would be equivalent to the acres of a newly

constructed Plan B template (i.e. restore a Plan B at TY30). No additional marsh material

will be added.

The NER Plan is fully described in the Integrated Feasibility Study and Final

Environmental Impact Statement Report, Section 3.6.

L6.12 First Component of Construction

A separate analysis was conducted on the individual islands of the NER Plan resulting in

the selection of the first component of construction that could be constructed within the


6-16

budget. The first component of construction consists of restoration of Whiskey Island to

its minimal geomorphologic form and ecologic function along with five (5) years of

advanced fill (Plan C) and two renourishment events, one at TY20 to add Plan C and the

other one at TY40 to add Plan B.

The first component of construction is fully described in the Final Integrated Feasibility

Study and Final Environmental Impact Statement Report, Section 3.7.


7-1

L7. CONSTRUCTION PROCEDURES AND ACCESS

L7.1 BEACH AND DUNE FILL

Based on professional experience and related CWPPRA project construction methods, it

is anticipated that the contractor will use a hydraulic cutterhead dredge plant to excavate

sand from the available sand borrow areas. Environmental laws protecting sea turtles

could possibly require the cessation of work for a limited time if the allowable number of

sea turtles killed is exceeded during dredging. The sand will then be pumped through a

series of booster pumps to the beach/dune fill template via a submerged sediment

pipeline.

During construction the contractor will be directed to maintain dedicated equipment

loading/unloading areas, staging areas, and access corridors to minimize the impacts to

the island. Existing mangrove habitats and prior restoration project areas shall be

avoided by construction equipment and construction-related activities.

Once on the beach, the sediment pipeline will run parallel to the shoreline. Front-end

loaders that are equipped with grapple arms will be utilized in the placement and

relocation of the sediment pipeline. For segments of the fill template that have sufficient

width, a Y-valve will be utilized to enable placement of multiple sediment pipelines

along the template. The bifurcation of the discharge pipeline will facilitate lower

discharge velocities and increased sediment retention within the fill template. In order to

minimize the impact on piping plover, the beach will be constructed in sections to allow

the birds to move to areas that are not currently under construction.

The sand will be worked on the beach by bulldozers to meet the specified template

grades, slopes and widths. Construction methods may vary but it is anticipated that sand

placement along the shoreline will be controlled by advancing a temporary sand dike

several hundred feet parallel to shore ahead of the discharge terminus. This aids in

reducing initial fill losses offshore and helps control temporary turbidity that may result

from the fill placement operations. Typically water drainage and discharges will be

directed offshore into the Gulf of Mexico or into existing marsh areas to nourish these

habitats.

L7.2 BACK-BARRIER MARSH FILL

Based on professional experience and related CWPPRA project construction methods, it

is anticipated that the contractor will use a hydraulic cutterhead dredge and booster

pump(s) to excavate sediment from the available offshore marsh borrow area(s) and

directly transport it via a submerged sediment pipeline to the marsh platform. As with the

beach fill, environmental laws protecting sea turtles could possibly require the cessation

of work for a limited time if the allowable number of sea turtles killed is exceeded during

dredging. However, turtles are typically able to avoid cutterhead dredge intakes because

the dredges move along the seabed at such a slow speed.


7-2

Sediment used to construct the marsh containment dikes will be dredged from existing

material inside the marsh creation area rather than from offshore borrow areas.

Therefore, dredging operations associated with the containment dikes are not expected to

adversely impact sea turtles.

These operations will be done in a manner that will minimize turbidity. Discharge and

dewatering from the marsh fill shall typically be directed towards the Gulf of Mexico

including orienting discharge pipes such that the hydraulic flow moves in a gulfward

direction and locating dewatering structures on the gulf side of the Study Area. The

contractor may employ other methods such as building interior containment dikes and

creating a drainage gradient towards the gulf. If excess turbidity occurs, the contractor

will be directed to change the operating procedure to reduce the degree of turbidity.

L7.3 CONSTRUCTION ACCESS

The required land based equipment including but not limited to graders, loaders, dozers,

and marsh buggy backhoes will be transported from the mainland to the islands via

barge(s). The contractor will excavate access channels from the Gulf of Mexico or the

back bays to the islands utilizing barge mounted clamshell dredges with temporary

sidecast disposal. Exact access to the beach/dune and marsh fill templates will be

determined and coordinated during the Planning, Engineering, and Design phase and will

include the necessary easements. The contractor will be required to submit a

construction access plan which shall contain provisions for restoring any damaged

habitats.

Miscellaneous equipment to be stored on the beach may include sediment pipeline,

graders, loaders, dozers, marsh buggy backhoes, weirs, grade stakes, light towers, fuel

tanks with containment, welding machine, and temporary shanty for personnel. Further,

the contractor will locate a quarters barge in an appropriate sheltered staging area to

house the land based personnel and office facilities.


8-1

L8. ADAPTIVE MANAGEMENT PLAN (OPERATIONS AND

MAINTENANCE)

The details for post-construction monitoring and adaptive management activities

proposed for the Study along with estimates of cost and duration are presented in

Appendix I. A description of O&M activities and estimates of cost for O&M are

presented in Section L9.


9-1

L9. COST ESTIMATES

L9.1 CONCEPTUAL COST ESTIMATES

The conceptual cost estimates for each island restoration measure utilizing one or more of

the sand and marsh borrow areas were determined by computing the costs based on

equipment types and estimates of production rates, historical contract bids from projects

of a similar nature, and professional experience. Conceptual costs were developed for

individual islands in order to evaluate each measure on a level and consistent basis. Each

island restoration estimate included a dredge plant for beach/dune fill and a dredge plant

for marsh fill. Each dredge equipment cost estimate included pipeline, equipment

mobilization/demobilization, and support plant. This method allowed for

interchangeability of dredge type for beach/dune fill and marsh fill to evaluate the most

efficient method of island restoration.

The costs derived were provided as inputs to the USACE Institute for Water Resources

(IWR) Planning Suite which assists with formulation and comparison of alternative plans.

The IWR analysis is fully described in Appendix K. The IWR model was employed to

determine which island measure or combinations of island measures would be cost

effective.

L9.1.1 Basis

The basis of the conceptual cost estimates were comprised of the following items:

Mobilization / Demobilization

The mobilization/demobilization costs included the anticipated plant and equipment to be

used in the excavation, transportation, and placement of beach, dune and marsh fill.

Separate mobilization/demobilization costs were developed for the beach/dune and marsh

fill components in the event that independent dredge types would be used for the different

fill elements. This provided the flexibility to use a hopper dredge or a cutterhead dredge

for beach/dune fill and a cutterhead dredge for marsh fill construction. The derived costs

were then compared to historic contract bids from the USACE and CWPPRA projects of

a similar nature.

Surveying

Surveying costs included a daily rate for survey crew, survey vessel, and survey

equipment, multiplied by the sum of the predicted sediment pumping duration, weather

days, and mobilization days. Additional costs included a lump sum for survey crew

travel and the installation and maintenance of marsh fill grade stakes.


9-2

Access Channel

Access channel costs were based on a unit cost per linear foot and derived from historical

contract bids. The linear footage of the access channel for each island was estimated as

the length of the northern containment dike.

Marsh Fill

Marsh fill volume was estimated using the BICM 2006 survey data, adjusted to account

for background erosion and the effects of relative sea level rise between the date of the

BICM survey and the anticipated start date of construction. Equipment costs were

estimated by considering the daily rate for the cutterhead dredge and booster pump(s),

fuel, per foot pipeline costs, and supporting equipment costs. The estimated equipment

daily rates were then multiplied by the estimated construction duration, which was based

on production rate, weather days, and mobilization/demobilization days. The unit cost

per cubic yard for marsh fill was calculated by dividing the equipment total cost by the

volume of marsh fill required.

Containment Dikes

Containment dikes are included in each island plan to provide sediment retention during

marsh fill placement and to prevent sediment overflow into vegetative areas requiring

protection from construction activities. The containment dikes are built with in-situ

sediment. Containment dike linear footage is the sum of the northern and southern marsh

retention dikes and, if required, the vegetative protection dikes. The containment dike

unit cost per linear foot was derived from historical contract bids.

Beach / Dune Fill

Beach/dune fill volumes were estimated using the BICM 2006 surveys and adjusted to

account for background erosion and the effects of relative sea level rise between the date

of the BICM survey and the anticipated start date of construction. Equipment costs were

estimated by considering the daily rate for the cutterhead or hopper dredge and booster

pump(s), fuel, per foot pipeline costs, and supporting equipment costs. The estimated

equipment daily costs were then multiplied by the estimated construction duration, which

was based on production rate, weather days, and mobilization/demobilization days. The

unit cost per cubic yard of beach/dune fill was calculated by dividing the equipment total

cost by the volume of beach/dune fill required.

Breakwaters / Terminal Groin

Breakwater and terminal groin conceptual costs were developed following review of the

contract bids for the CWPPRA breakwater extension project on Raccoon Island (TE-48)

completed in 2008. Unit cost per ton for boulders; unit cost per square yard for

geotextile; and lump sum costs for mobilization/demobilization, construction surveys,

and quality control were developed and applied to the breakwater and terminal groin

preliminary designs that incorporated these elements.


9-3

Sea Turtle Relocation

Sea turtle relocation trawling is used during hopper dredge operations in areas where

turtles are known or suspected to be present. Relocation trawling is conducted using nets

constructed to USACE specifications. The location of this Study Area is ideally suited

for low cost mobilization/demobilization to due to the abundance of available trawlers in

coastal Louisiana that could be contracted for this task. An approved National Marine

Fisheries Service observer must be present during all relocation surveys. Sea turtle

relocation costs were developed using historical contract bids.

Inspection / Construction Administration

The construction inspection costs were estimated by multiplying the inspector daily rate

by the sediment pumping duration, weather days, and demobilization days. The

construction inspector costs also included a lump sum cost for travel. The construction

administration costs were estimated by multiplying the administration daily rate by the

estimated construction duration along with a lump sum cost for travel.

L9.1.2 Assumptions

The following assumptions were used in the development of the conceptual cost

estimates.

Dredge and Supporting Plant

The use of hopper and cutterhead suction dredges were evaluated as methods of sediment

excavation. Consideration of both dredges allowed for the selection of the most cost

effective method of island restoration. Following review of available hopper dredge fleet

information, a 6,000 cubic yard (cy) hopper dredge was selected for use in the

comparative costing analysis between island plans. A similar review was conducted for

the cutterhead suction dredge, with the 30" dredge being selected. Supporting plant

consist of booster pumps, support vessels, and other ancillary equipment. The following

assumptions were used in the development of production rates and equipment cost for

each dredge type and for each island:

Hopper Dredge

Hopper dredge capacity: 6,000 cy (5,100 cy retained)

Hopper dredge duration: 24 hours/day

Hopper dredge pump horsepower: 4,500 Hp

Hopper dredge propulsion horsepower: 5,000 Hp


9-4

Cutterhead Suction Dredge

Cutterhead suction dredge size: 30"

Cutterhead suction dredge duration: 20 hours/day

Cutterhead suction dredge horsepower: 9,000 Hp

Booster Pumps

Booster pump horsepower: 5,200 Hp

Support Plant

Support plant horsepower: 1,000 Hp

Applying these assumptions, production rates were calculated using the Cutter Suction

Dredge Cost Estimating Program (CSDCEP) developed by the Center for Dredging

Studies, Zachry Department of Civil Engineering, Texas A&M University. Inputs for the

production rate calculations for cutterhead suction dredge were average pipeline length

from the borrow area to fill area, bank height, general sediment characteristics, and the

dredge size. The hopper dredge inputs were the same as the cutterhead suction dredge

with the exception of the pipeline length and the addition of vessel speed, sailing

distance, and dredging depth. The offshore pipeline length for the hopper dredge was set

at two miles, which is the average distance from the shoreline to water depths which

would accommodate a loaded 6,000cy hopper dredge. Applying these inputs to the

CSDCEP program yielded production rates for each dredge type. For the cutterhead

suction dredge, the production rate and the number of booster pumps required were

outputs. For the hopper dredge, the outputs included the estimated cycle time and

volume per cycle.

General Construction

The following is a listing of the general conceptual construction assumptions applied in

the development of the conceptual cost estimates:

Mobilization time: 30 days

Demobilization time: 30 days

Beach and Dune fill dredge-to-fill ratio: 1.3:1

Marsh fill dredge-to-fill ratio: 1.6:1

Dredge-to-fill ratios account for losses during excavation and transport of the material

and overfill. Design fill quantities account for sea level rise, subsidence, and initial fill

compaction.

L9.1.3 Contingencies

Based on professional experience, a 25% contingency was chosen for developing the

conceptual cost estimates. This contingency was included to account for uncertainties in

the development of the cost estimates including such things as fuel costs, contractor

availability at the time of bidding, weather-related downtime during construction, and fill

volume adjustments needed to construct the selected fill templates at time of


9-5

construction. To reduce the uncertainties in the fill volume calculations, historical

shoreline erosion rates, land loss rates, and the effects of relative sea level rise were

applied to predict the background erosion that would be experienced from the date of the

design survey to the actual construction period. These background erosion losses were

applied to the island design templates as they were formulated.

L9.1.4 Refined Conceptual Cost Estimates

Following development of the conceptual cost estimates and initial IWR model results,

combinations of island restorations were analyzed. As described in Section L9.1, the

conceptual cost estimates were developed separately for individual islands and their

associated beach/dune and marsh fill components. The initial conceptual cost estimates

did not account for potential reductions due to shared mobilization and demobilization as

well as other fixed costs. The conceptual cost estimates were re-evaluated and

redundancies in cost components were eliminated. The reductions resulted in a single

dredge mobilization/demobilization and associated mobilization/demobilization days for

the combinations where the same dredge plant was selected for beach/dune and marsh

fill. Redundant support plant cost was also eliminated and remaining support plant cost

was shared between beach/dune and marsh fill components. Finally, redundant pipeline

cost for beach/dune and marsh fill was eliminated, carrying forward only the longest

pipeline length from borrow area to fill area that is required for each island in the

combination. After removing redundant costs for the dredge plant and associated

pipeline for each of the marsh and sand borrow areas, costs for relocating the pipeline

from the sand borrow area to the marsh borrow area and from island to island were

computed and included in the refined conceptual cost estimate.

L9.2 PRELIMINARY COST ESTIMATES

The preliminary cost estimates were developed for the island restoration alternatives in

the Intermediate Array (Appendix K). These preliminary cost estimates built on the

refined conceptual cost estimates with the inclusion of planning, engineering, and design;

real estate easements; sand fencing; vegetative plantings; monitoring; and operation and

maintenance.

L9.2.1 Basis

The basis of the preliminary cost estimates included the basis of the conceptual and

refined conceptual cost estimates, defined in Section L9.1.1, along with the additional

elements listed above.

Planning, Engineering & Design

The Planning, Engineering & Design Phase (PED) is the phase during which the design is

finalized, plans and specifications are prepared and reviewed, and a construction contract is

prepared for advertising consistent with USACE Engineering Regulation ER1110-2-1150

(USACE, 1999). The preliminary cost estimate for PED was based on professional experience.


9-6

Real Estate Easements

Easements and acquisitions were evaluated on a preliminary level for comparative

purposes at this stage of alternative formulation. East Timbalier Island is the only island

that contains oil and gas infrastructure that would be impractical to provide access to

through canals. Acquisition of these structures was preliminarily estimated at 2% of the

construction cost of this island. Access canals for Timbalier Island were relatively short

and incorporated into the construction cost for containment dikes and access channels.

All other islands did not possess oil and gas facilities or wells.

Sand Fencing

The design parameters for the sand fencing included a 4-foot high fence with 50%

porosity (i.e., ratio of area of open space to total fence area) placed shore-parallel along

the entire length of the dune to capture wind-blown sand and to help build and stabilize

mounds. The sand fencing unit cost per linear foot was derived from historical contract

bids

Vegetative Plantings

Vegetative planting cost estimates were derived from the analyses of historical contract

bids and current recommendations for other LCA and CWPPRA projects in design.

These cost estimates should be considered as preliminary only and should be amended as

the site conditions warrant during PED. The design parameters for the vegetative

planting plan are as follows.

Dune and Supratidal Platform

Based on professional experience, aerial dispersion of grass seed should be conducted on

the dune and supratidal platform if construction completion occurs in the summer or fall

months to provided ground cover during the winter, until vegetative plantings can be

accomplished. As the time of completion of construction can not be determined at this

time, aerial seeding was included in the preliminary cost estimate as a conservative

measure.

Herbaceous plantings for the dune and supratidal platform included a mixture of species

comprised of some or all of the following: bitter panicum (Panicum amarum var amarum

Fourchon), sea oats (Uniola paniculata Caminada), marshhay cordgrass (Spartina

patens Gulf Coast) and gulf cordgrass (Spartina spartinae). Species recommendations

should be re-evaluated during PED when accurate soil properties, site conditions, salinity,

and final elevations are determined. Herbaceous planting of the dune and supratidal areas

would be conducted in the first year following construction.


9-7

Marsh Platform

Herbaceous planting for the marsh intertidal platform included smooth cordgrass

(Spartina alterniflora Vermilion). Planting of the marsh intertidal platform would be

over 100% of the area on 8-foot centers. The herbaceous planting would be conducted in

two phases. Phase one would plant 50% coverage of the marsh platform in second year

following construction, with the remaining 50% coverage planted in third year following

construction.

Woody Species

Woody species for the dune and supratidal swale areas included matrimony vine (Lycium

barbarum), wax myrtle (Morella cerifera), iva (Iva imbricata), eastern baccharis

(Baccharis halimifolia), and hercules club (Zanthoxylum clava-herculis). Species

recommendations should be re-evaluated during PED when accurate soil properties, site

conditions, salinity, and final elevations are determined. Woody species would be

planted on the dune and supratidal swale areas 15% coverage in the second year

following construction.

Aerial Seeding

Aerial seeding will be conducted over the dune / swale and marsh habitat areas with the

appropriate seed species for the time of year following completion of construction

activities.

Supervision and Inspection

Independent supervision and inspection during the construction phase is included to insure

construction proceeds as scheduled, designed, and permitted. The preliminary cost estimates for

supervision and inspection were based on professional experience.

Monitoring

An effective monitoring program will be required to determine if the outcomes are

consistent with original goals and objectives. The monitoring plan consists of

bathymetric and topographic surveys; aerial photography to define habitat classification

and shoreline position; geotechnical sampling to determine sediment properties; and

analysis of all data collected (Appendix I). The preliminary cost estimates for monitoring

were based on professional experience.

Operations and Maintenance

The O&M elements included the measures outlined in the Adaptive Management Plan

(Appendix I). The preliminary cost estimates for O&M were based on professional

experience. O&M also included maintenance of the hard structural measures included in

the Final Array, specifically the Raccoon Island breakwaters or terminal groin (Section

L6). Based on the effects of relative sea level rise and performance of the TE-48

breakwaters, maintenance was projected at TY10. The maintenance costs included 25%

of the initial rock volume along with mobilization/demobilization, quality control, and

surveying.


9-8

L9.2.2 Assumptions

The assumptions made in the development of the preliminary cost estimates included the

assumptions made for the conceptual and refined conceptual cost estimates, defined in

Section L9.1.2.

L9.2.3 Contingencies

Based on professional experience, a 25% contingency was chosen for developing the

preliminary cost estimates for all elements. This overall contingency was included to

account for uncertainties in the development of the cost estimates including such things

as fuel costs, contractor availability at the time of bidding, weather-related downtime

during construction, and fill volume adjustments needed to construct the selected fill

templates at time of construction. To reduce the uncertainties in the fill volume

calculations, historical shoreline erosion rates, land loss rates, and the effects of relative

sea level rise were applied to predict the background erosion that would be experienced

from the date of the design survey to the actual construction period. These background

erosion losses were applied to the island design templates as they were formulated.

L9.3 DETAILED COST ESTIMATE

Detailed cost estimates were developed for the NER Plan. The estimates include

mobilization/demobilization; beach/dune fill placement; marsh fill placement;

containment dikes; access channel; sand fencing; vegetative plantings; surveying; PED;

construction management; adaptive management; and post-construction monitoring.

The NER Plan includes the following restorations and renourishments:

Whiskey Island to its minimal geomorphologic form and ecologic function along

with 5 years of advanced fill, followed by renourishment to the same plan in

Target Year (TY) 20 and a second renourishment to the minimum

geomorphologic form and ecological function only, in TY40;

Trinity Island to its minimal geomorphologic form and ecologic function along

with 5 years of advanced fill, followed by renourishment to the same plan in

TY25;

Raccoon Island to its minimal geomorphologic form and ecologic function along

with25 years of advanced fill with the addition of a terminal groin on the western

beach fill boundary, followed by renourishment in TY30 to the minimum

geomorphologic form and ecological function only. O&M of the terminal groin

would be accomplished in TY10; and

Timbalier Island to its minimal geomorphologic form and ecologic function along

with 25 years of advanced fill with renourishment to the minimum

geomorphologic form and ecological function only in TY30.

The costs for the renourishment events include mobilization/demobilization; beach/dune

fill placement; sand fencing; vegetation planting (dune/supratidal platform only);

surveying; PED; and construction administration.


9-9

The NER Plan costs were subdivided into two contracts for initial restoration and

individual contracts for renourishments or O&M. Contract No. 1 consists of the initial

restoration of Whiskey Island, Trinity Island, and Raccoon Island with terminal groin.

Contract No. 2 consists of initial restoration of Timbalier Island. The individual O&M

and renourishment contracts are Raccoon Island terminal groin O&M (No. 3), Whiskey

Island renourishment in TY20 (No. 4), Trinity Island renourishment in TY25 (No. 5),

Raccoon Island and Timbalier Island renourishment in TY30 (No. 6), and Whiskey Island

renourishment in TY40 (No. 7).

The first component of construction is a subset of the NER Plan consisting of initial

restoration of Whiskey Island to its minimal geomorphologic form and ecologic function

along with 5 years of advanced fill, followed by renourishment to the same plan in TY20

and a second renourishment to the minimum geomorphologic form and ecological

function only, in TY40.

Unit costs for beach/dune and marsh fill were developed in the USACE Corps of

Engineers Dredge Estimating Program (CEDEP) program. The dredge plant selected was

a 30 cutterhead suction dredge and associated plant consisting of booster pumps, support

vessels, and other ancillary equipment. The unit costs were added to the cost

development in the MII software. Risk analyses were performed and provided the cost

contingency at an 80% confidence level for the initial restoration of the NER Plans and

the first component of construction. A fixed cost contingency percentage was applied to

the renourishment events based on professional judgement. A construction schedule was

developed and total costs were determined through escalation to mid-point of design,

construction, and monitoring.

L9.3.1 Basis

Fill Material Sourcing

The NER Plan would utilize beach/dune and marsh material from a combination of

Whiskey Island Restoration Borrow Area 3, New Cut Borrow Area 4, Raccoon Island

Restoration Borrow Area 5, South Pelto Borrow Area 6, and Ship Shoal Borrow Area 7

(Section L1). Table L9-1 presents the required fill and cut volumes per borrow area for

the NER Plan with renourishments.

The first component of construction would utilize beach/dune and marsh material from a

combination of Whiskey Island Restoration Borrow Area 3 and Ship Shoal Borrow Area

7 (Section L1). Table L9-2 presents the required fill and cut volumes per borrow area for

the first component of construction with renourishments


9-10

Table L9-1. NER Plan Borrow Areas and Cut Volumes

Borrow Area

Beach/Dune

Fill Volume

(cy)

Marsh Fill

Volume

(cy)

Dredgeto-Fill

Ratio

Beach/Dune

Cut Volume

(cy)

Marsh Cut

Volume

(cy)

Ship Shoal

Borrow Area 7 17,500,000 2,760,000 1.13:1 19,800,000 3,120,000

South Pelto

Borrow Area 6 10,700,000 3,080,000 1.13:1 12,090,000 3,480,000

 4,790,000

1.6:1

upper

layer

 7,660,000 Whiskey Island

Restoration

Borrow Area 3  3,630,000

1.3:1

lower

layer

 4,720,000

New Cut

Borrow Area 4  1,920,000 1.3:1  2,500,000

Initial Restoration

Raccoon Island

Restoration

Borrow Area 5

 1,850,000 1.3:1  2,400,000

Ship Shoal

Borrow Area 7 20,400,000  1.13:1 23,100,000 

Renourishment

South Pelto

Borrow Area 6 470,000  1.13:1 531,000 


9-11

Table L9-2. First Component of Construction Borrow Areas and Cut Volumes

Borrow Area

Beach/Dune

Fill Volume

(cy)

Marsh Fill

Volume

(cy)

Dredgeto-Fill

Ratio

Beach/Dune

Cut Volume

(cy)

Marsh Cut

Volume

(cy)

Ship Shoal

Borrow Area 7 8,330,000  1.13:1 9,410,000 

Initial

Restoration

Whiskey Island

Restoration

Borrow Area 3

 580,000

1.6:1

upper

layer

 928,000

Renourish

-ment

Ship Shoal

Borrow Area 7 14,700,000  1.13:1 16,600,000 

Beach/Dune Fill Placement

For beach/dune construction the sand will be worked bulldozers to meet the specified

template grades, slopes and widths. Construction methods may vary but it is anticipated

that sand placement along the shoreline will be controlled by advancing a temporary sand

dike several hundred feet parallel to shore ahead of the discharge terminus. This aids in

reducing initial fill losses offshore and helps control temporary turbidity that may result

from the fill placement operations. Typically water drainage and discharges will be

directed offshore into the GOM or into existing marsh areas to nourish these habitats.

The fill quantities for the beach/dune component of the initial restoration and

renourishments of the NER Plan and first component of construction are listed in Table

L9-3.

Marsh Fill Placement

For marsh construction the fill material will be directed into the fill cells with the aid of a

marsh backhoe directing the discharge pipeline. Discharge and dewatering from the

marsh fill shall typically be directed towards the GOM including orienting discharge

pipes such that the hydraulic flow moves in a gulfward direction and locating dewatering

structures on the gulf side of the Study Area. The contractor may employ other methods

such as building interior containment dikes and creating a drainage gradient towards the

gulf. If excess turbidity occurs, the contractor will be directed to change the operating

procedure to reduce the degree of turbidity. Fill quantities for the marsh component of

the initial restoration of the NER Plan and first component of construction are listed in

Table L9-3.


9-12

Table L9-3. NER Plan and First Component of Construction

Required Fill Quantities Breakdown

NER Plan with Renourishments Fill Area Quantity (CY)

Beach/Dune 8,330,215 Whiskey Is. Initial Construction Marsh 579,724

Beach/Dune 3,813,885 Trinity Is. Initial Construction Marsh 3,772,925

Beach/Dune 5,381,956 Raccoon Is. Initial Construction Marsh 4,609,709

Beach/Dune 10,702,818 Timbalier Is. Initial Construction Marsh 9,073,317

Whiskey Is. Renourishment TY20 Beach/Dune 8,330,215

Trinity Is. Renourishment TY25 Beach/Dune 3,813,885

Raccoon Is. Renourishment TY30 Beach/Dune 1,946,212

Timbalier Is. Renourishment TY30 Beach/Dune 470,203

Whiskey Is. Renourishment TY40 Beach/Dune 6,359,650

First Component of Construction

with Renourishments Fill Area Quantity (CY)

Beach/Dune 8,330,215 Whiskey Is. Initial Construction Marsh 579,724

Whiskey Is. Renourishment TY20 Beach/Dune 8,330,215

Whiskey Is. Renourishment TY40 Beach/Dune 6,359,650

Submerged and Shore Pipeline Relocations

Submerged pipeline relocations will be required during construction to facilitate the

utilization of the different borrow areas for beach/dune and marsh restoration

Relocations of the shore pipeline would be accomplished at the completion of the fill

activities on each island. Costs were developed for the extraction and reinstallation of the

submerged portions of the pipeline from one borrow area to another and the relocations

of the shore pipeline segments These costs include equipment and crews to perform the

work at an assumed rate of 1,500 feet per day.

Construction Access

The required land based equipment including but not limited to graders, loaders, dozers,

and marsh buggy backhoes will be transported from the mainland to the islands via

barge(s). The contractor will excavate access channels from the GOM to the islands

utilizing barge mounted clamshell dredges with temporary sidecast disposal. Exact

access to the beach/dune and marsh fill templates will be determined and coordinated

during PED and will include the necessary easements. The contractor will be required to

submit a construction access plan which shall contain provisions for restoring any

damaged habitats.

Miscellaneous equipment to be stored on the beach may include sediment pipeline,

graders, loaders, dozers, marsh buggy backhoes, weirs, grade stakes, light towers, fuel


9-13

tanks with containment, welding machine, and temporary shanty for personnel. Further,

the contractor will locate a quarters barge in an appropriate sheltered staging area to

house the land based personnel and office facilities.

Sand Fencing and Vegetative Plantings

Following fill placement, sand fencing and vegetative plantings will be installed. The

sand fences are porous barriers that reduce wind speed along the coast such that sand

being transported by the wind accumulates on the downwind side of the fence. The sand

fences will promote deposition of windblown sand, create dune features, reduce

trampling of existing dunes by beach visitors, and protect vegetative plantings.

Following construction, vegetative plants would commence as described in Section

L9.2.1 for the dune and supratidal platform.

L9.3.2 Assumptions

Assumptions used during the development of the detailed cost include the following:

Single dredge plant would be utilized per contract;

Dredge: 30" cutterhead dredge of 9,200Hp operating at 16 hours per day;

Boosters: 7,200Hp;

Construction access would be constructed concurrent with the mobilization and

preparation activities; and

Marsh fill containment dikes would be constructed concurrent with beach/dune

fill placement (Initial Restoration only).

L9.3.3 MCACES

The Tri-Services Automated Cost Engineering System (TRACES MII Version 3.01) was

used to develop the baseline project cost for the NER Plan and first component of

construction. MII is the second generation of the MCASES software used as a costing

tool by the USACE. The MII English Cost Book 2008, National Labor 2008 -

Preliminary Draft, and the MII Equipment Region 3r 2007 libraries were linked to the

project library in the development of these costs. Elements of the restoration were

assigned to feature codes following the Civil Works Work Breakdown Structure. The

feature codes utilized in the project library include:

[01] Lands and Damages;

[06] Fish & Wildlife (Adaptive Management Plan);

[10] Breakwaters & Seawalls (the NER Plan only);

[17] Beach Replenishment;

[30] Planning, Engineering & Design (PED); and

[31] Construction Management.

A summary of the restoration elements is presented below and a detailed report of the

MII cost estimate for the NER Plan and first component of construction can be found in

Annex L-4.


9-14

Lands and Damages

Whiskey, Trinity, and Raccoon Islands are owned in entirety by the State of Louisiana.

Timbalier Island is owned in majority by the State of Louisiana. Cost for Lands and

Damages were obtained from the USACE Real Estate Division.

Fish & Wildlife (Adaptive Management Plan)

The Adaptive Management Plan is comprised of three elements. These included the

Adaptive Management Plan program setup, Adaptive Management Plan implementation,

and post construction monitoring. Program setup will commence and run concurrently

with PED. Implementation and post construction monitoring will begin following initial

restoration and continue for a period of up to 10 years. The Adaptive Management Plan

is detailed in Appendix I.

Breakwaters and Seawalls

Breakwaters and Seawalls feature code is comprised of the elements of construction of

the terminal groin on Raccoon Island for the NER Plan. Costs were developed for

mobilization/demobilization, survey crews, quality control inspector, equipment, rip-rap

rock, and geotextile underlayment.

Beach Replenishment

Beach replenishment encompasses the elements of construction including the

mobilization/demobilization of the sediment delivery pipeline, installation and removal of

shore and submerged pipeline, construction crews, water-borne and land-based

equipment, dredge and plant, beach/dune and marsh fill and associated activities,

relocations of the submerged pipeline from sand borrow area to marsh borrow area, sand

fencing, and vegetative plantings.

Mobilization / Demobilization of Sediment Delivery Pipeline

The costs associated with mobilization and demobilization of the submerged pipeline was

developed based on the required equipment and crews to handle the pipeline from its

home base to the job site. The equipment element specified the number and horsepower

of the tugs necessary for transporting the pipeline in floating rafts of 6,000 feet each. The

mobilization/demobilization of the floating and shore pipeline was incorporated as part of

the dredge and plant mobilization/demobilization costs.

Shore Pipeline Installation / Removal

The costs associated with the installation and removal of the shore segments of the

pipeline was developed based on the required equipment and crews needed to work the

pipeline within the fill templates. Stand-by times and costs associated with these

activities were also incorporated in these costs.

Submerged Pipeline Installation / Removal

The costs associated with the installation and removal and/or relocation of the submerged

pipeline were developed based on the required equipment and crews needed to work the


9-15

pipelines from the borrow areas to the fill templates. Stand-by times and costs associated

with these activities were also incorporated in these costs.

Dredge Mobilization / Demobilization

The costs associated with mobilization and demobilization of the dredge, plant, and

floating and shore pipeline were developed in the USACE CEDEP program and input to

the MII cost analysis as a lump sum costs.

Beach / Dune Fill

A unit price for beach/dune fill was developed in the USACE CEDEP program and was

based on the required fill material for the fill area, anticipated dredge-to-fill ratio losses,

pumping distance, and dredge capacity. The unit price was entered into the MII cost

estimate as in-place costs for fill and multiplied by the required volume to derive costs

for the material only. Pay for fill material as in-place has been utilized on prior

restoration projects as a means to promote "Best Management Practices" by the

construction contractor.

Beach / Dune Construction

This category estimates the costs associated with the shore work required for shaping and

grading the in-place fill material for the beach and dune. It included the costs for the

required equipment and crews for the duration of constructing this feature.

Survey Crews

The costs for survey crews were developed in two phases, shore crew and offshore crew.

The different equipment and crews required for the two distinctly different survey types

lead to the development of these costs as separate entities. The shore based survey crew

requires a survey chief and several rodmen to conduct the upland segments of the survey

prior to, during, and following fill placement. The offshore crew required the inclusion

of a survey vessel and operator for borrow area and nearshore bathymetric profile data

collection.

Pipeline Crews

Similar to the survey crews, the pipeline crews require different personnel and equipment

to maintain the sediment delivery pipeline. The shore crew is responsible for adding or

removing pipeline as required by the alongshore advancement of the fill template. The

equipment associated with these activities included bulldozers and pipeline segment

handlers commonly called skidders. The offshore pipeline crews required additional

personnel such as welders and crane operators. The offshore pipeline crews utilized

equipment such as barges, cranes, welding machines, and air compressors to maintain the

submerged sections of the sediment delivery pipeline

Marsh Fill (Initial Restoration Only)

A unit price for marsh fill was developed in the USACE CEDEP program and was based

on the required fill material for the borrow area, anticipated dredge-to-fill ratio, pumping

distance, and dredge capacity. The unit price was entered into the MII cost estimate as

in-place costs for fill and multiplied by the required volume to derive a cost for the

material only.


9-16

Marsh Fill Grade Stakes (Initial Restoration Only)

Marsh fill grade stakes are utilized to determine the elevations of fill in the marsh fill

template prior to consolidation of the material to a point where egress is possible. The

stakes are constructed with a graduation placard such that the elevation of the material

can be measured through a sight glass and manually recorded in a survey book. The

stakes are placed in the fill template prior to fill activities and conventionally placed on a

grid of 150 feet by 250 feet. The unit cost for the grade stakes were based on prior marsh

construction bids and inflated to 2009 dollars.

Marsh Fill Construction, Survey, and Pipeline Crews (Initial Restoration Only)

The marsh fill construction activities requirements for crews and equipment mimic that

associated with beach/dune fill with minor differences in shore based equipment.

Access Channel

The unit cost for the access channel was derived from recent construction project bids

and inflated to 2009 dollars. The channel length was developed from the feasibility level

island design as the length of the northern marsh containment dike for the initial

restoration and a fixed distance for renourishments since marsh containment would not be

required. A more detailed estimate of access channel length will be determined

following the final design survey in PED.

Containment Dikes

The unit cost per linear foot for containment dikes were derived from recently

constructed project bids and inflated to 2009 dollars. The total length of the containment

dikes was a summation of the island design lengths for the northern marsh containment

dike and the beach/dune and marsh separation dike for initial restoration and only the

beach/dune and marsh separation dike for renourishment events.

Sand Fencing

The sand fencing unit cost per linear foot was developed from recently constructed

project bids and inflated to 2009 dollars. The required sand fencing length was derived

from the island design length of the dune feature.

Vegetative Plantings

A detailed description of the vegetative planting scheme and species was presented in

Section L.9.1 for initial restoration and are consistent with past and planned Louisiana

barrier island restoration projects. The beach/dune fill segment is the only component

selected for renourishment. Vegetative plantings of the dune and supratidal, woody

species, and aerial seeding of the renourishment areas will follow the same methodology

as the plantings schemes for initial restoration. The unit costs for the various plant

species were developed from analyses of past project bids and planned restoration effort

estimates and inflated to the cost year for this restoration.

Planning, Engineering & Design

Planning, Engineering & Design encompasses the final design and engineering during

construction. The elements include project management, planning & environmental


9-17

compliance, engineering & design, engineering technical review, contracting &

reprographics, engineering during construction, planning during construction and project

operations.

Construction Management

Construction Management is comprised of three elements; actual construction

management, project operations administration, and overall project management.

L9.3.4 Risk Analysis

Risk analyses are required for any project whose cost exceeds $40 Million. The intent of

a risk analysis was to determine the probability of various cost outcomes and schedule

variances to quantify the required contingency needed in the cost estimate to achieve a

level of cost confidence. The risk analysis process used the Monte Carlo technique to

determine probabilities and contingencies for the project. This technique is incorporated

into an add-on to Microsoft Excel and is commonly referred to as Crystal Ball. The

resultant confidence levels express the probability that the corresponding contingency

amount will cover the cost of the project being studied. The Cost Engineering Dx

guidance for cost risk analysis focuses on risk and opportunity potential, all project

features, and internal and external risks to the project. The standard confidence level

recommended by the Cost Engineering Dx is 80%. The risk analysis was performed for

the initial restoration of the NER Plan and the first component of construction. Details of

the risk analyses for cost and schedule are presented in the Risk Analysis Reports found

in Annex L-5.

The following are those elements analyzed in the cost and schedule risk models to

determine the appropriate contingencies.

Beach/Dune and Marsh Fill Design Quantities

The island designs were developed utilizing survey data collected in 2006 as part of

BICM (UNO and USGS, 2009). Through the use of shoreline erosion and landloss rates

in the above referenced program, the fill volumes required in 2012 for beach/dune and

marsh were calculated. A risk variance of +/-10% of the required volume was used to

evaluate the risk associated with a decrease or increase in the erosional effects

experienced by the island during this six year period. The variances in beach/dune and

marsh required volumes were analyzed as separate risk elements so as to assess the risk if

the beach/dune and marsh fill template experience differing erosional influences.

Geotechnical Issues with the Beach/Dune and Marsh Fill Borrow Areas

The sediment characteristics of the proposed borrow areas for beach/dune and marsh

construction were analyzed from data collected within these borrow sources as part of

designs for other restoration projects. Projected dredge-to-fill ratios were established and

used in the production estimates for the dredge during construction of the beach/dune and

marsh fill templates. To quantify variances induced by differing sediment characteristics


9-18

that could be experienced within the borrow areas proposed for beach/dune fill and the

marsh fill, differing ratios better than and worse than the most likely dredge-to-fill were

evaluated for their affect on the construction costs. Sediment characteristics are one of

three driving forces in determining production rates for the dredging equipment.

Sponsor's Ability to Fund Its Share

A delay of eighteen and six months in the procurement of funds to begin construction of

the NER Plan and first component of construction, respectively were evaluated. The low

risk was assumed to be the same as the most likely schedule for construction. The high

risk was analyzed as a delay for the beginning of construction.

Fuel Prices

Overall affects of fuel prices on construction cost were analyzed. The most likely fuel

price was derived from an average of fuel prices for 2009. A lower risk assumes the

price of fuel would fall by as much as 25% from the 2009 average. A higher risk

assumes that a volatile market could increase fuel prices by as much as 60% above the

2009 average price.

Severe Weather Downtime

The effects of dredging material in the open GOM on the dredge's effective operational

hours per day were evaluated. A dredge may experience higher average operational time

per day during periods of favorable weather and conversely experience lower than

average operational time during periods of increases sea state such as during winter

months. The most likely case, worst case, and best case operational times per day were

established by review of USACE prior dredging projects. Operational time of the

dredging equipment is one of three driving forces in determining production rates for the

dredging equipment.

Delays due to Design Modifications

Following pre-construction surveys of the fill templates, design modification may be

required to adjust the fill templates to maximize effectiveness of the island restoration.

Through prior restoration project experience of the design team, a two month delay in

beginning construction was considered as the high risk variance for the project schedule.

Long Pipeline to Island for Beach/Dune Fill

In development of the dredging production rates, it was determined that it was feasible to

construct the beach/dune fill template using as few as two boosters from the borrow area

to the fill template. The most likely number of boosters the contractor would use is three

to maintain higher production rates. The number of booster pumps utilized in the

delivery of sediment to the fill template is one of three driving forces in determining the

production rates for the dredging equipment. Construction cost and schedule variances

were calculated to evaluate the affects on project cost and schedule if the contractor chose

to utilize only two booster pumps during the construction of the beach/dune fill template.


9-19

Bidder's Risk in a Volatile Market

The affects on construction costs of based on the risk assumed by the contractor were

analyzed. These risks are those carried by the contractors that are not analyzed in other

risk elements of this model. Those risks analyzed elsewhere include fuel prices, pipeline

steel prices, weather delays, dredge acquisition, and additional mobilizations due to

hurricanes. Examples of volatile market risk include, but are not limited to, other

projects out for bid requiring the contractor's resources, labor force prices, and

construction equipment availability. A low risk assumes the contractor is eager for the

contract and would bid 10% less than the most likely and conversely a high risk indicates

the contractor may be over extending his resources and submits a bid 25% higher than the

most likely construction cost.

Pipeline Steel Prices

The risk associated with the changing price per pound of steel was analyzed to determine

it's affect on the cost of the sediment delivery pipeline. Utilizing pricing from prior

USACE projects, the assumed current cost per pound for steel was set a $0.60, the low

price at $0.45, and the high price at $1.50. These prices were used in the determination

of unit cost variances for beach/dune and marsh fill.

Dredge Acquisition

The risk associated with the availability of dredges for restoration construction at the time

of notice to proceed for the contractor was considered. The delay to the construction

schedule, while awaiting a dredge to become available from another project, was

determined to be six months.

Hurricane Demobilization / Re-mobilization

For the possibility of a hurricane affecting the project during construction, an additional

demobilization/re-mobilization of the crew, equipment, and dredge to safe harbor was

evaluated.

Key Findings and Observations

The key cost risk drivers for the NER Plan identified through sensitivity analysis for the

initial restoration component of Contract No. 1 (Whiskey, Trinity, and Raccoon Islands)

are Internal Risks PED-11 (Geotechnical Issues Beach/Dune - Ship Shoal Borrow Area)

in additional to External Risks PR-2 (Fuel Prices), PR-3 (Severe Weather/Downtime),

PR-5 (Long Pipeline to Island for Beach Fill), PR-7 (Bidders Risk in Volatile Market),

and PR-8 (Pipeline Steel Prices) which together contribute 99.3% of the statistical cost

variance.

The key cost risk drivers for the NER Plan identified through sensitivity analysis for the

initial restoration component of Contract No. 2 (Timbalier Island) are Internal Risk PED11 (Geotechnical Issues Beach/Dune - South Pelto Borrow Area) in addition to External

Risks PR-2 (Fuel Prices), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to


9-20

Island for Beach Fill), PR-7 (Bidders Risk in Volatile Market), and PR-8 (Pipeline Steel

Prices) which together contribute 99.3% of the statistical cost variance.

The key schedule risk drivers identified through sensitivity analysis for the initial

restoration component of the NER Plan are External Risks PR-1 (Sponsors Ability to

Fund its Share), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to Island for

Beach Fill), PR-4 (Delays due to Design Modifications), and PR-10 (Dredge

Acquisition), which together contribute 96.4% and 97.4% of the statistical schedule

variance for Contracts No. 1 and No 2, respectively.

Following the execution of the simulations on the risk models, the key cost risk drivers

identified through sensitivity analysis for the first component of construction are Internal

Risk PED-11 Geotechnical Issues Beach/Dune Borrow Area) and External Risks PR-2

(Fuel Prices), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to Island for

Beach Fill), PR-7 (Bidders Risk in Volatile Market) which together contribute 96.4% of

the statistical cost variance.

The key schedule risk drivers identified through sensitivity analysis for the first

component of construction are External Risks PR-1 (Sponsors Ability to Fund its Share),

PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to Island for Beach Fill), and

PR-10 (Dredge Acquisition), which together contribute 91.8% of the statistical cost

variance.

L9.4 TOTAL PROJECT COST SUMMARY

The Total Project Cost Summary (TPCS) is the culmination of the estimated project cost

derived from the MII cost development, contingency percentage determined from the risk

analyses, and the escalation to mid-point year quarter for the different elements of the

initial restoration of the NER Plan and first component of construction. This summation

provides a fully funded project cost estimate for initial restoration of the NER Plan and

first component of construction. Each of the elements used in the development of the

TPCS are described in the following sub-sections. The TPCS is presented in Annex L-6.

L9.4.1 Contingencies

National Ecosystem Restoration Plan

Since the NER Plan contained two separate contracts for the initial restorations, two

independent risk analyses were performed. A cost contingency value of 27.4% and

29.4% was derived from the Crystal Ball analysis for the project costs at an 80%

confidence level for Contracts No. 1 and No. 2, respectively. A schedule contingency

value of 44.9% and 48.6% was derived from the analysis for the project schedule at an

80% confidence level for Contracts No. 1 and No. 2, respectively. The risk analyses

focused on the risks and opportunities associated with all features of the NER Plan.

Comparisons of the 50%, 80%, and 100% confidence levels for cost and schedule of the

NER Plan's initial restoration are presented in Tables L9-4 through L9-7.


9-21

Table L9-4. Baseline Cost Estimate w/Contingency Summary

(NER Plan Initial Restoration, Contract No. 1)

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

Total

Contingency

($1,000) 1

Baseline Cost

Estimate

($1,000) 2

50% Confidence

Level - Initial

Restoration

Project Cost

$260,000 17.9% $47,000 $307,000

80% Confidence

Level - Initial

Restoration

Project Cost

$260,000 27.4% $71,000 $331,000

100% Confidence

Level - Initial

Restoration

Project Cost

$260,000 60.3% $157,000 $417,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from Risk Analysis Forecast

Table L9-5. Baseline Schedule w/Contingency Summary

(NER Plan Initial Restoration, Contract No. 1)

Risk Analysis Forecast

Crystal Ball

Forecast

Schedule

Total

Contingency

Crystal Ball

Forecast Schedule

50% Confidence Level -

Initial Restoration

Project Duration

64.5 months 34.7% 86.9 months

80% Confidence LevelInitial Restoration

Project Duration

64.5 months 44.9% 93.5 months

100% Confidence Level

- Initial Restoration

Project Duration

64.5 months 75.3% 113.1 months


9-22

Table L9-6. Baseline Cost Estimate w/Contingency Summary

(NER Plan Initial Restoration, Contract No. 2)

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

Total

Contingency

($1,000) 1

Baseline Cost

Estimate

($1,000) 2

50% Confidence

Level - Initial

Restoration

Project Cost

$245,000 19.3% $47,000 $292,000

80% Confidence

Level - Initial

Restoration

Project Cost

$245,000 29.4% $72,000 $317,000

100% Confidence

Level - Initial

Restoration

Project Cost

$245,000 66.0% $162,000 $407,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from Risk Analysis Forecast

Table L9-7. Baseline Schedule w/Contingency Summary

(NER Plan Initial Restoration, Contract No. 2)

Risk Analysis Forecast

Crystal Ball

Forecast

Schedule

Total

Contingency

Crystal Ball

Forecast Schedule

50% Confidence Level -

Initial Restoration

Project Duration

55.8 months 37.3% 76.6 months

80% Confidence LevelInitial Restoration

Project Duration

55.8 months 48.6% 82.9 months

100% Confidence Level

- Initial Restoration

Project Duration

55.8 months 83.7% 102.5 months

For the terminal groin O&M and renourishment events scheduled at TY10, TY20, TY25,

TY30, and TY40, a cost contingency of 35% was selected based on professional

judgment.

First Component of Construction

Contingencies for the initial restoration of the first component of construction were

developed through the utilization of the Risk Register and Crystal Ball software as

described in Section L9.4.4 Risk Analysis. A cost contingency value of 27.7% was

derived from the Crystal Ball analysis for the project costs at an 80% confidence level. A

schedule contingency value of 33.8% or 11.7 months was derived from the analysis for


9-23

the project schedule at an 80% confidence level. The risk analysis focused on the risks

and opportunities associated with all features of the first component of construction.

Comparisons of the 50%, 80%, and 100% confidence levels for cost and schedule of the

first component of construction initial restoration are presented in Tables L9-8 and L9-9,

respectively.

Table L9-8. Baseline Cost Estimate w/Contingency Summary

(First Component of Construction Initial Restoration)

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

Total

Contingency

($1,000) 1

Baseline Cost

Estimate

($1,000) 2

50% Confidence

Level - Initial

Restoration

Project Cost

$90,100 18.4% $16,600 $107,000

80% Confidence

Level - Initial

Restoration

Project Cost

$90,100 27.7% $24,990 $115,000

100% Confidence

Level - Initial

Restoration

Project Cost

$90,100 59.2% $53,320 $143,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from Risk Analysis Forecast

Table L9-9. Baseline Schedule w/Contingency Summary

(First Component of Construction Initial Restoration)

Risk Analysis Forecast

Crystal Ball

Forecast

Schedule

Total

Contingency

Crystal Ball

Forecast Schedule

50% Confidence Level -

Initial Restoration

Project Duration

34.6 months 26.3% 43.7 months

80% Confidence LevelInitial Restoration

Project Duration

34.6 months 33.8% 46.3 months

100% Confidence Level

- Initial Restoration

Project Duration

34.6 months 54.6% 53.5 months

For the renourishment events scheduled at TY20 and TY40, a cost contingency of 35%

was selected based on professional judgment.


9-24

L9.4.2 Project Cost Estimate

The project cost for initial restoration and renourishment events of the NER Plan and first

component of construction were developed in the MII software and escalated from the

estimate price year to the program price year with contingencies added. Tables L9-10

and L9-11 presents the project cost for the program year of 2012 for each of the major

project elements of the initial restoration with contingency for the NER Plan and first

component of construction, respectively.

Table L9-10. NER Plan Initial Restoration Project Cost Summary

Program Year (2012)

Project Element Program

Year Cost 2 Contingency 1

Program

Year Total

Cost 2

Lands & Damages $545,000 $164,000 $709,000

Fish & Wildlife

(Adaptive Management Plan) $5,820,000 Included $5,820,000

Breakwaters & Seawalls $1,830,000 508,000 2,330,000

Beach Replenishment $463,000,000 $131,000,000 $593,000,000

Planning, Engineering & Design $23,000,000 $6,590,000 $30,000,000

Construction Management $23,000,000 $6,590,000 $30,000,000

NER Plan Initial Restoration

Project Costs $518,000,000 $144,000,000 $661,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

Table L9-11. First Component of Construction Initial Restoration Project Cost

Summary - Program Year (2012)

Project Element Program

Year Cost 2 Contingency 1

Program

Year Total

Cost 2

Lands & Damages $51,000 $15,000 $67,000

Fish & Wildlife

(Adaptive Management Plan) $5,820,000 Included $5,820,000

Beach Replenishment $78,000,000 $22,000,000 $100,000,000

Planning, Engineering & Design $3,920,000 $1,090,000 $5,010,000

Construction Management $3,920,000 $1,090,000 $5,010,000

First Component of Construction

Initial Restoration

Project Costs

$92,000,000 $23,920,000 $116,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS


9-25

L9.4.3 Project Schedule

Funding for this project is anticipated for October 2011 with the initial construction

beginning in June 2012.

National Ecosystem Restoration Plan

Initial Restoration Contract No.1 - Whiskey, Trinity, and Raccoon Islands

PED is anticipated to begin on December 31, 2010 with the Adaptive Management Plan

(AMP) program setup and initial monitoring beginning at the start of PED and continuing

through construction. The implementation of the AMP and post construction monitoring

for both contracts is anticipated to begin at the completion of construction for the initial

restoration and run for 10 years. The following is a listing of the anticipated dates of

construction elements for Contract No. 1.

Mobilization: June 2012 to July 2012

Beach/Dune Fill for Whiskey Island: July 2012 to July 2013

Beach/Dune Fill for Trinity Island: July 2013 to April 2014

Marsh Fill for Trinity Island: April 2014 to November 2014

Marsh Fill for Whiskey Island: November 2014 to February 2015

Beach/Dune Fill for Raccoon Island: February 2015 to October 2015

Terminal Groin for Raccoon Island: October 2015 to November 2015

Marsh Fill for Raccoon Island: October 2015 to May 2016

Demobilization: May 2016 to June 2016

Vegetative Planting would commence in the Spring of 2017.

Initial Restoration Contract No. 2 - Timbalier Island

PED and AMP for Contract No. 2 would run concurrent with that of Contract No. 1. The

following is a listing of the anticipated dates of construction elements for Contract No. 2.

Mobilization: June 2012 to August 2012

Beach/Dune Fill for Timbalier Island: August 2012 to June 2014

Marsh Fill for Timbalier Island: June 2014 to August 2015

Demobilization: August 2015 to October 2015

Vegetative Planting would commence in the Spring of 2016.

Operations & Maintenance and Renourishments

O&M and renourishment events are scheduled as follows:

O&M of terminal groin at Raccoon Island at TY10

Renourishment of Whiskey Island at TY20

Renourishment of Trinity Island at TY25

Renourishment of Raccoon and Timbalier Islands at TY30

Renourishment of Whiskey Island at TY40


9-26

First Component of Construction

Mid-point of construction for the first component of construction would occur in

February 2013 with construction being completed in October 2013. PED is anticipated to

begin on December 31, 2010 with the AMP program setup and initial monitoring

beginning at the start of PED and continuing through construction. The implementation

of the AMP and post construction monitoring is anticipated to begin at the completion of

construction for the initial restoration and run for 10 years. Renourishments would be

conducted in TY20 and TY40.

Refer to Section L11 for additional schedule description details for the NER Plan and

first component of construction.

L9.4.4 Fully Funded Project Cost

The fully funded project costs were developed in the TPCS spreadsheet for initial

restoration of the NER Plan and first component of construction. The TPCS requires

inputs on the baseline project cost, price level of estimate, project schedule, and project /

schedule contingency. The TPCS formulates the fully funded cost through a summation

of baseline cost and contingencies and escalates this to mid point of duration for each

specific element. The elements of the TPCS for this project include the Lands &

Damages, Adaptive Management Plan, Beach Replenishment, PED, and Construction

Management. Tables L9-12 and L9-13 presents a summary of the results from the TPCS

for the fully funded initial restoration of the NER Plan and first component of

construction, respectively.

Table L9-12. Fully Funded Cost Summary for NER Plan Initial Restoration

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $545,000 $169,000 $715,000

Fish & Wildlife

(Adaptive Management Plan) $5,820,000 Included $5,820,000

Breakwaters & Seawalls $1,830,000 $661,000 $2,490,000

Beach Replenishment $463,000,000 $156,000,000 $619,000,000

Planning, Engineering & Design $23,000,000 $6,850,000 $30,000,000

Construction Management $23,000,000 $7,800,000 $31,000,000

NER Plan Initial Restoration

Fully Funded Costs $518,000,000 $171,000,000 $689,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS


9-27

Table L9-13. Fully Funded Cost Summary for First Component of Construction

Initial Restoration

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $51,000 $16,000 $67,000

Fish & Wildlife

(Adaptive Management Plan) $5,820,000 Included $5,820,000

Beach Replenishment $78,000,000 $25,000,000 $103,000,000

Planning, Engineering & Design $3,920,000 $1,120,000 $5,040,000

Construction Management $3,920,000 $1,240,000 $5,160,000

First Component of Construction

Initial Restoration

Fully Funded Costs

$92,000,000 $27,000,000 $119,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

The base cost for the renourishment efforts developed in the MII were escalated to the

mid points of construction through the use and expansion of the cost index trends

available in the Civil Works Construction Cost Index System (EM 1110-2-1304, March

30, 2010). The fully funded cost for O&M and renourishments are presented in Tables

L9-14 through L9-18. Renourishment events for the first component of construction are

a subset of those for the NER Plan and include the Whiskey Island TY20 and TY40.

Table L9-14. Fully Funded Cost Summary for TY10 Terminal Groin O&M

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $51,000 $33,000 $84,000

Breakwaters & Seawalls $627,000 $443,000 $1,070,000

Planning, Engineering & Design $63,000 $41,000 $104,000

Construction Management $64,000 $45,000 $109,000

TY10 Terminal Groin O&M

Fully Funded Costs $805,000 $565,000 $1,370,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS Simulation


9-28

Table L9-15. Fully Funded Cost Summary for Whiskey Is. TY20 Renourishment

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $51,000 $45,000 $96,000

Beach Replenishment $73,000,000 $70,000,000 $143,000,000

Planning, Engineering & Design $3,650,000 $3,360,000 $7,010,000

Construction Management $3,650,000 $3,510,000 $7,160,000

TY20 Renourishment

Fully Funded Costs $80,000,000 $77,000,000 $157,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS Simulation

Table L9-16. Fully Funded Cost Summary for Trinity Is. TY25 Renourishment

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $51,000 $54,000 $105,000

Beach Replenishment $50,000,000 $56,000,000 $106,000,000

Planning, Engineering & Design $2,490,000 $2,760,000 $5,250,000

Construction Management $2,480,000 $2,860,000 $5,340,000

TY25 Renourishment

Fully Funded Costs $55,000,000 $62,000,000 $117,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS Simulation

Table L9-17. Fully Funded Cost Summary for Raccoon and Timbalier Is.

TY30 Renourishment

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $443,000 $567,000 $1,000,000

Beach Replenishment $37,000,000 $51,000,000 $88,000,000

Planning, Engineering & Design $1,840,000 $2,460,000 $4,300,000

Construction Management $1,840,000 $2,550,000 $4,390,000

TY30 Renourishment

Fully Funded Costs $41,000,000 $56,000,000 $97,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS Simulation


9-29

Table L9-18. Fully Funded Cost Summary for Whiskey Is. TY40 Renourishment

Project Element Program Year

Cost 2

All

Contingencies

& Escalations 1

Fully Funded

Total 2

Lands & Damages $51,000 $91,000 $142,000

Beach Replenishment $58,000,000 $110,000,000 $167,000,000

Planning, Engineering & Design $2,880,000 $5,350,000 $8,190,000

Construction Management $2,880,000 $5,480,000 $8,350,000

TY40 Renourishment

Fully Funded Costs $63,000,000 $121,000,000 $184,000,000

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS Simulation

The fully funded cost developed for the NER Plan with renourishments is estimated at

$1,246,000,000. Using the same methods for costing as that used for the NER Plan, the

fully funded cost for the first component of construction with renourishments is estimated

at $461,000,000.


10-1

L10. RELOCATIONS

Whiskey, Trinity, and Raccoon Islands are owned in entirety by the State of Louisiana.

Timbalier Island is owned in majority by the State of Louisiana. There are no oil/gas

infrastructure or facilities that would require relocation for the restorations of the NER

Plan or first component of construction.


11-1

L11. SCHEDULE

L11.1 DESIGN SCHEDULE

The design schedule follows the elements of the PED outlined in Engineering Regulation

ER1110-2-1150 (USACE, 1999) which include: project reformulation; documentation of

design; technical review conference; design documentation reports; permit applications;

value engineering; hazardous, toxic, and radioactive waste assessments; relocations;

physical model studies; preparation of the project cooperation agreement; preparation of

plans and specifications; independent government estimates; review of NEPA document;

and independent technical review.

On a project following the full normal authorization process, the PED phase begins when

the Major Subordinate Command Commander issues the public notice for the feasibility

report and PED funds are allocated to the district. PED generally requires a period of up

to two years, depending on the complexity of the project, and ends with completion of the

plans and specifications for the first construction contract or as otherwise defined in the

PED cost-sharing agreement. Engineering functions shall be prepared to begin an

intensive effort immediately upon notification that PED funds are available.

For the LCA TBBSR Study, it is estimated this phase will last approximately 17 months.

Time should be saved because the alternatives analysis, fill template designs, and borrow

area identification were completed as part of the engineering feasibility study. Surveys,

volume calculations, and cost estimate will have to be updated at the design level prior to

completing final plans and specifications. PED is anticipated to begin on December 31,

2010.

L11.2 CONSTRUCTION SCHEDULE

L11.2.1 NER Plan Initial Restoration Schedule

Construction funds authorization is anticipated in October 2011 with construction

beginning in June 2012. The construction schedule consists of project mobilization /

demobilization and construction access, beach / dune and marsh fill placement, and

pipeline relocation for each island. Restoration activities for the NER Plan are

anticipated to begin in June 2012 and be concluded in July 2016. A construction element

and duration summary for ach contract are listed below.

Contract No. 1 - Whiskey Island, Trinity Island, and Raccoon Island with Terminal

Groin

Mobilization:

o Mobilize Pipeline: The sediment delivery pipeline shall take

approximately 14 days to mobilize from home port to the project site (June

2012).


11-2

o Mobilize Equipment and Crew: This involves moving all shore based crew

and equipment to the project site and would take approximately 8 days

(July 2012)

o Mobilize Dredge: Mobilization of the cutterhead dredge is anticipated to

require 14 days. (July 2012)

Pre-lay of Pipeline

o Pre-lay Shore Pipeline: The anticipated duration to pre-lay 5,656 feet of

shore pipeline on Whiskey Island is 11 days. Shore pipeline will be

installed prior to beach/dune fill construction in July 2012.

o Pre-lay of Submerged Pipeline: The anticipated duration to pre-lay 62,908

feet of submerged pipeline from Ship Shoal to Whiskey Island is 42 days.

Submerged pipeline will be installed prior to beach/dune fill construction

in June - July 2012.

Access Channel - Whiskey Island: Construction of the access channel is estimated

to progress at 500 feet per day based on review of prior projects. There is

estimated to be 5,000 feet of access channel required for the mobilization of shore

equipment to begin construction of the containment dike south with construction

duration of 10 days. Access channel on Whiskey Island will commence in June

2012 in order to have the equipment and crews on site for the completion of prelaying shore pipeline to be commensurate with the completion of the installation

of the submerged pipeline in July 2012.

Containment Dike South (CDS) - Whiskey Island: The CDS separates the

beach/dune fill from the marsh fill and will be constructed concurrently with the

installation of the sediment pipelines and beach/dune fill. Construction of the

CDS is estimated to progress at 400 feet per day based on review of prior projects.

There is estimated to be 17,918 feet of CDS required for Whiskey Island requiring

45 days for construction (June - August 2012).

Beach/Dune Fill - Whiskey Island: Dredge and fill activities for Whiskey Island

beach/dune would require the excavation and placement of 8,330,215 cubic yards

(in-place) of sands from Ship Shoal. This is calculated to take 325 days. (July

2012 to June 2013)

Sand Fencing - Whiskey Island: Sand fencing along the dune of Whiskey Island is

estimated to require 18,075 feet of materials and be installed at 900 feet/day.

Sand fencing installation would commence following beach/dune construction

and be completed in 20 days (June - July 2013).

Pipeline Relocation (Ship Shoal-Whiskey Is. to Ship Shoal-Trinity Is.)

o Pickup Shore Pipeline: Following beach/dune construction on Whiskey

Island, the shore pipeline would be removed for relocation to Trinity

Island. This involves the removal of 11,071 feet of shore pipe requiring

22 days (June - July 2013).


11-3

o Pickup Submerged Pipeline: Following beach/dune construction on

Whiskey Island, the submerged pipeline must be relocated from the

orientation of Ship Shoal-Whiskey Island to Ship Shoal-Trinity Island.

This requires the removal of 62,908 feet of submerged pipeline at a pace

of 1,500 feet per day and is anticipated to take 42 days (June - July 2013).

o Pre-lay Shore Pipeline: The anticipated duration to pre-lay 13,088 feet of

shore pipeline on Trinity Island is 26 days. Shore pipeline will be

installed prior to beach/dune fill construction on during the period of

August - September 2013.

o Pre-lay Submerged Pipeline: Installation of 77,280 feet of submerged

pipeline from Ship Shoal to Trinity Island is anticipated to take 52 days.

Submerged pipeline will be installed prior to beach/dune fill construction

during the period of July - September 2013.

Access Channel - Trinity Island: There is estimated to be 5,000 feet of access

channel required for the mobilization of shore equipment to begin construction of

the CDS with construction duration of 10 days. Access channel on Trinity Island

will commence on August 14, 2013 in order to have the equipment and crews on

site for the completion of pre-laying shore pipeline to be commensurate with the

completion of the relocation of the submerged pipeline in September 2013.

Containment Dike South - Trinity Island: The CDS separates the beach/dune fill

from the marsh fill and will be constructed concurrently with the relocation of the

sediment pipelines and beach/dune fill. There is estimated to be 17,918 feet of

CDS required for Trinity Island requiring 56 days for construction (August -

October 2013).

Beach/Dune Fill - Trinity Island: Dredge and fill activities for Trinity Island

beach/dune would require the excavation and placement of 3,813,885 cubic yards

(in-place) of sands from Ship Shoal. This is calculated to take 163 days

(September 2013 - March 2014).

Sand Fencing - Trinity Island: Sand fencing along the dune of Trinity Island is

estimated to require 22,434 feet of materials and installation would commence

following beach/dune construction and be completed in 25 days (March 2014).

Containment Dike North (CDN) - Trinity Island: The CDN separates the marsh

fill from the back bay and will be constructed concurrently with the relocation of

the sediment pipelines. There is estimated to be 22,237 feet of CDN required for

Trinity Island requiring 56 days for construction (March - May 2014).

Pipeline Relocation (Ship Shoal-Trinity Is. to Whiskey 3A-Trinity Is.)

o Pickup Submerged Pipeline: Following beach/dune construction on

Trinity Island, the submerged pipeline must be relocated from the

orientation of Ship Shoal-Trinity Island to Whiskey 3A borrow areaTrinity Island. This requires the removal of 77,280 feet of submerged

pipeline and is anticipated to take 52 days (March 6 - April 27, 2014).


11-4

o Pre-lay Submerged Pipeline: Installation of 15,889 feet of submerged

pipeline from Whiskey 3A to Trinity Island is anticipated to take 11 days.

Submerged pipeline will be installed prior to marsh fill construction

during the period of April - May 2014.

Marsh Fill - Trinity Island: Dredge and fill activities for Trinity Island marsh

would require the excavation and placement of 3,772,925 cubic yards (in-place)

of mud/silt from Whiskey Island 3A borrow area. This is estimated to take 190

days (May - November 2014).

Containment Dike North - Whiskey Island: The CDN separates the marsh fill

from the back bay and will be constructed concurrently with the relocation of the

sediment pipelines. There is estimated to be 7,370 feet of CDN required for

Whiskey Island requiring 19 days for construction (November - December 2015).

Pipeline Relocation (Whiskey 3A-Trinity Is. to Whiskey 3A-Whiskey Is.)

o Pickup Shore Pipeline: Following marsh construction on Trinity Island,

the shore pipeline would be removed for relocation to Whiskey Island.

This involves the removal of 24,315 feet of shore pipe requiring 49 days

(November 2014 - January 2015).

o Pickup Submerged Pipeline: Following marsh construction on Trinity

Island, the submerged pipeline must be relocated from the orientation of

Whiskey 3A-Trinity Island to Whiskey 3A-Whiskey Island. This requires

the removal of 15,889 feet of submerged pipeline and is anticipated to take

11 days (November 2014).

o Pre-lay Shore Pipeline: The anticipated duration to pre-lay 5,656 feet of

shore pipeline on Whiskey Island is 11 days. Shore pipeline will be

installed prior to marsh fill construction in January 2015.

o Pre-lay Submerged Pipeline: Installation of 34,288 feet of submerged

pipeline from Whiskey 3A to Whiskey Island is anticipated to take 23

days. Submerged pipeline will be installed prior to marsh fill construction

during the period of November - December 2015.

Marsh Fill - Whiskey Island: Dredge and fill activities for Whiskey Island marsh

would require the excavation and placement of 579,724 cubic yards (in-place) of

mud/silt from Whiskey Island 3A borrow area. This is estimated to take 23 days

(January - February 2015).

Access Channel - Raccoon Island: There is estimated to be 5,000 feet of access

channel required for the mobilization of shore equipment to begin construction of

the CDS with construction duration of 10 days. Access channel on Raccoon

Island will commence in February 2015 in order to have the equipment and crews

on site for the completion of pre-laying shore pipeline to be commensurate with

the completion of the relocation of the submerged pipeline in April 2015.


11-5

Containment Dike South - Raccoon Island: The CDS separates the beach/dune fill

from the marsh fill and will be constructed concurrently with the relocation of the

sediment pipelines. There is estimated to be 20,609 feet of CDS required for

Raccoon Island requiring 52 days for construction (February - April 2015).

Pipeline Relocation (Whiskey 3A-Whiskey Is. to Ship Shoal-Raccoon Is.)

o Pickup Shore Pipeline: Following marsh construction on Whiskey Island,

the shore pipeline would be removed for relocation to Raccoon Island.

This involves the removal of 11,071 feet of shore pipe requiring 22 days

(February - March 2015).

o Pickup Submerged Pipeline: Following marsh construction on Whiskey

Island, the submerged pipeline must be relocated from the orientation of

Whiskey 3A-Whiskey Island to Ship Shoal-Raccoon Island. This requires

the removal of 34,288 feet of submerged pipeline and is anticipated to take

23 days (February - March 2015).

o Pre-lay Shore Pipeline: The anticipated duration to pre-lay 10,183 feet of

shore pipeline on Raccoon Island is 20 days. Shore pipeline will be

installed prior to beach/dune fill construction in March 2015.

o Pre-lay Submerged Pipeline: Installation of 56,721 feet of submerged

pipeline from Ship Shoal to Raccoon Island is anticipated to take 38 days.

Submerged pipeline will be installed prior to beach/dune fill construction

during the period of March - April 2015.

Beach/Dune Fill - Raccoon Island: Dredge and fill activities for Raccoon Island

beach/dune would require the excavation and placement of 5,381,956 cubic yards

(in-place) of sands from Ship Shoal. This is calculated to take 204 days (April -

October 2015).

Sand Fencing - Raccoon Island: Sand fencing along the dune of Raccoon Island is

estimated to require 12,186 feet of materials and installation would commence

following beach/dune construction and be completed in 14 days (October -

November 2015).

Raccoon Island Terminal Groin: Mobilization/demobilization and construction is

estimated to take 48 days and commence with the completion of the beach/dune

fill on Raccoon Island (October - December 2015)

Containment Dike North - Raccoon Island: The CDN separates the marsh fill

from the back bay and will be constructed concurrently with the beach/dune fill

for Raccoon Island. There is estimated to be 12,505 feet of CDN required for

Raccoon Island requiring 31 days for construction (September - October 2015).

Marsh Fill - Raccoon Island Component 1: Dredge and fill activities for Raccoon

Island marsh component 1 would require the excavation and placement of

2,763,555 cubic yards (in-place) of sand from Ship Shoal borrow area. This is

estimated to take 109 days (October 2015 - February 2016).


11-6

Pipeline Relocation (Ship Shoal-Raccoon Is. to Raccoon BA-Raccoon Is.)

o Pickup Submerged Pipeline: Following beach/dune and marsh component

1 construction on Raccoon Island, the submerged pipeline must be

relocated from the orientation of Ship Shoal-Raccoon Island to Raccoon

borrow area-Raccoon Island. This requires the removal of 56,721 feet of

submerged pipeline and is anticipated to take 38 days (February - March

2016).

o Pre-lay Submerged Pipeline: Installation of 26,503 feet of submerged

pipeline from Raccoon BA to Raccoon Island is anticipated to take 18

days. Submerged pipeline will be installed during the period of March -

April 2016.

Marsh Fill - Raccoon Island Component 2: Dredge and fill activities for Raccoon

Island marsh component 2 would require the excavation and placement of

1,846,154 cubic yards (in-place) of mud/silt from Raccoon borrow area. This is

estimated to take 48 days (April - May 2016).

Pickup of Pipeline

o Pickup Shore Pipeline: Following fill activities on the island 13,675 feet of

shore pipeline will be broken down and readied for transport from

Raccoon Island. These activities are anticipated to require 27 days. (May -

June 2016)

o Pickup Submerged Pipeline: Following fill activities on Raccoon Island;

26,503 feet of submerged pipeline will be broken down and readied for

transport. These activities are anticipated to require 18 days. (May - June

2016)

Demobilization:

o Demobilize Pipeline: Demobilization of the sediment pipeline is

anticipated to take 14 days. (June - July 2016)

o Demobilize Equipment and Crews: Demobilization of the shore equipment

and crews is anticipated to take 8 days. (June - July 2016)

o Demobilize Dredge: Demobilization of the dredge is anticipated to take 14

days. (May - June 2016)

Vegetative Plantings:

o Plantings - TY1: Aerial Seeding and Dune/Swale planting will take place

during the appropriate season in Target Year 1.

 Whiskey Island: Anticipated April - May 2014

 Trinity Island: Anticipated April - May 2015

 Raccoon Island: Anticipated April - May 2016

o Plantings - TY2: Woody Species and 50% Marsh Fill plantings will take

place during the appropriate season in Target Year 2.

 Whiskey Island: Anticipated April - May 2015

 Trinity Island: Anticipated April - May 2016

 Raccoon Island: Anticipated April - May 2017


11-7

o Plantings - TY3: Remaining 50% Marsh Fill plantings will take place

during the appropriate season in Target Year 3.

 Whiskey Island: Anticipated April - May 2016

 Trinity Island: Anticipated April - May 2017

 Raccoon Island: Anticipated April - May 2018

Contact No. 2 (Timbalier Island)

Mobilization:

o Mobilize Pipeline: The sediment delivery pipeline shall take

approximately 14 days to mobilize from home port to the project site (June

2012).

o Mobilize Equipment and Crew: This involves moving all shore based crew

and equipment to the project site and would take approximately 8 days

(July 2012)

o Mobilize Dredge: Mobilization of the cutterhead dredge is anticipated to

require 14 days. (June 2012)

Pre-lay of Pipeline

o Pre-lay Shore Pipeline: The anticipated duration to pre-lay 12,068 feet of

shore pipeline on Timbalier Island is 24 days. Shore pipeline will be

installed prior to beach/dune fill construction during the period of July -

August 2012.

o Pre-lay of Submerged Pipeline: The anticipated duration to pre-lay 85,206

feet of submerged pipeline from South Pelto to Timbalier Island is 57

days. Submerged pipeline will be installed prior to beach/dune fill

construction during the period of June - August 2012.

Access Channel - Timbalier Island: Construction of the access channel is

estimated to progress at 500 feet per day based on review of prior projects. There

is estimated to be 5,000 feet of access channel required for the mobilization of

shore equipment to begin construction of the CDS with construction duration of

10 days. Access channel on Timbalier Island will commence in July 2012 in

order to have the equipment and crews on site for the completion of pre-laying

shore pipeline to be commensurate with the completion of the installation of the

submerged pipeline in August 2012.

Containment Dike South - Timbalier Island: The CDS separates the beach/dune

fill from the marsh fill and will be constructed concurrently with the installation

of the sediment pipelines and beach/dune fill. Construction of the CDS is

estimated to progress at 400 feet per day based on review of prior projects. There

is estimated to be 35,455 feet of CDS required for Whiskey Island requiring 89

days for construction (July - October 2012).


11-8

Beach/Dune Fill - Timbalier Island: Dredge and fill activities for Timbalier Island

beach/dune would require the excavation and placement of 10,702,818 cubic

yards (in-place) of sands from South Pelto. This is calculated to take 469 days.

(August 2012 - November 2013)

Sand Fencing - Timbalier Island: Sand fencing along the dune of Timbalier Island

is estimated to require 35,425 feet of materials and be installed at 900 feet/day.

Sand fencing installation would commence following beach/dune construction

and be completed in 39 days (November 2013 - January 2014).

Containment Dike North - Timbalier Island: The CDN separates the marsh fill

from the back bay and will be constructed concurrently with the beach/dune fill

for Timbalier Island. There is estimated to be 42,580 feet of CDN required for

Timbalier Island requiring 107 days for construction (August - November 2013).

Marsh Fill - Timbalier Island Component 1: Dredge and fill activities for

Timbalier Island marsh component 1 would require the excavation and placement

of 3,083,736 cubic yards (in-place) of sand from South Pelto borrow area. This is

estimated to take 130 days (November 2013 - April 2014).

Pipeline Relocation (South Pelto-Timbalier Is. to Whiskey 3A-Timbalier Is.)

o Pickup Submerged Pipeline: Following beach/dune and marsh component

1 construction on Timbalier Island, the submerged pipeline must be

relocated from the orientation of South Pelto-Timbalier Island to Whiskey

3A-Timbalier Island. This requires the removal of 85,206 feet of

submerged pipeline and is anticipated to take 57 days (April - June 2014).

o Pre-lay Submerged Pipeline: Installation of 82,796 feet of submerged

pipeline from Whiskey 3A to Timbalier Island is anticipated to take 55

days. Submerged pipeline will be installed during the period of June - July

2014.

Marsh Fill - Timbalier Island Component 2: Dredge and fill activities for

Timbalier Island marsh component 2 would require the excavation and placement

of 4,066,504 cubic yards (in-place) of mud/silt and sand from Whiskey 3A

borrow area. This is estimated to take 237 days (July 2014 - March 2015).

Pipeline Relocation (Whiskey 3A-Timbalier Is. to New Cut-Timbalier Is.)

o Pickup Submerged Pipeline: Following marsh component 2 construction

on Timbalier Island, the submerged pipeline must be relocated from the

orientation of Whiskey 3A-Timbalier Island to New Cut borrow areaTimbalier Island. This requires the removal of 82,796 feet of submerged

pipeline and is anticipated to take 55 days (March - May 2015).

o Pre-lay Submerged Pipeline: Installation of 38,881 feet of submerged

pipeline from New Cut to Timbalier Island is anticipated to take 26 days.

Submerged pipeline will be installed during the period of May - June

2015.


11-9

Marsh Fill - Timbalier Island Component 3: Dredge and fill activities for

Timbalier Island marsh component 3 would require the excavation and placement

of 1,923,077 cubic yards (in-place) of mud/silt and sand from New Cut borrow

area. This is estimated to take 61 days (June - August 2015).

Pickup of Pipeline

o Pickup Shore Pipeline: Following fill activities on the island 21,925 feet of

shore pipeline will be broken down and readied for transport from

Timbalier Island. These activities are anticipated to require 44 days.

(August - September 2015)

o Pickup Submerged Pipeline: Following fill activities on Timbalier Island;

38,881 feet of submerged pipeline will be broken down and readied for

transport. These activities are anticipated to require 26 days. (August -

September 2015)

Demobilization:

o Demobilize Pipeline: Demobilization of the sediment pipeline is

anticipated to take 14 days. (September 2015)

o Demobilize Equipment and Crews: Demobilization of the shore equipment

and crews is anticipated to take 8 days. (September - October 2015)

o Demobilize Dredge: Demobilization of the dredge is anticipated to take 14

days. (August 2015)

Vegetative Plantings:

o Plantings - TY1: Aerial Seeding and Dune/Swale planting will take place

during the appropriate season in Target Year 1. Anticipated April - May

2016

o Plantings - TY2: Woody Species and 50% Marsh Fill plantings will take

place during the appropriate season in Target Year 2. Anticipated April -

May 2017

o Plantings - TY3: Remaining 50% Marsh Fill plantings will take place

during the appropriate season in Target Year 3. Anticipated April - May

2018

L11.2.2 NER Plan O&M and Renourishment Construction Schedule

The PED process for the O&M and renourishments shall begin prior to the designated

TYs for the beginning of construction activities.

NER Plan - Terminal Groin O&M at TY10

O&M activities for the terminal groin at TY10 will follow the same schedule as the initial

construction. The require amount of rock to be placed in the O&M would be 25% of the

initial construction required volume.


11-10

NER Plan - Whiskey Island Renourishment at TY20

Renourishment of Whiskey Island at TY20 will follow the same schedule as the initial

construction with the exceptions that it will not involve marsh fill construction or marsh

fill vegetative planting. Dune/swale aerial seeding and planting should occur in TY21

and TY22. The volume of sediment required will be that needed to restore the

geomorphologic form and ecological function, plus accounting for five years of

background erosion/land loss.

NER Plan - Trinity Island Renourishment at TY25

Renourishment of Trinity Island at TY25 will follow the same schedule as the initial

construction with the exceptions that it will not involve marsh fill construction or marsh

fill vegetative planting. Dune/swale aerial seeding and planting should occur in TY26

and TY27. The volume of sediment required will be that needed to restore the

geomorphologic form and ecological function, plus accounting for five years of

background erosion/land loss.

NER Plan - Raccoon and Timbalier Island Renourishment at TY30

Renourishment of Raccoon and Timbalier Islands at TY30 will follow the same schedule

as the initial construction with the exceptions that it will not involve marsh fill

construction or marsh fill vegetative planting. Dune/swale aerial seeding and planting

should occur in TY31 and TY32. The volume of sediment required will be that needed to

restore the geomorphologic form and ecological function.

NER Plan - Whiskey Island Renourishment at TY40

Renourishment at TY40 will follow the same schedule as the initial construction with the

exceptions that it will not involve marsh fill construction or marsh fill vegetative

planting. Dune/swale aerial seeding and planting should occur in TY41 and TY42. The

volume of sediment required will be that needed to restore the geomorphologic form and

ecological function, plus accounting for five years of background erosion/land loss.

L11.2.3 First Component of Construction Initial Restoration Schedule

Construction funds authorization is anticipated in October 2011 with construction

beginning in June 2012. The construction schedule consists of project mobilization /

demobilization and construction access, beach / dune and marsh fill placement, and

pipeline relocation for each island. Restoration activities for the first component of

construction are anticipated to begin in June 2012 and be concluded on October 2013. A

construction element and duration summary is as follows:

Mobilization:

o Mobilize Pipeline: 62,908 feet of the sediment delivery pipeline shall take

approximately 14 days. This duration is to move the pipe to the site near

Whiskey Island. (June 2012)


11-11

o Mobilize Equipment and Crew: This involved moving all shore based

crew and equipment to the island. Mobilization of crew and shore

equipment would take approximately 8 days and begin with the

completion of the Access Channel. ( July 2012)

o Mobilize Dredge: Mobilization of the cutterhead dredge is anticipated to

require 14 days. (July 2012)

Access Channel is estimated to progress at 400 feet per day based on review of

prior projects. There is estimated to be 10,000 feet of access channel required

with construction duration of 25 days. Access channel will commence on June

13, 2012 in order to have the equipment and crews on site for the completion of

pre-laying shore pipeline to be commensurate with the completion of the

installation of the submerged pipeline. (June - July 2012)

Pre-lay of Pipeline

o Pre-Lay Shore Pipeline: The anticipated duration to pre-lay 5,656 feet of

shore pipeline is 11 days. Shore pipeline will be installed prior to

beach/dune fill construction in July 2012.

o Pre-Lay of Submerged Pipeline: The anticipated duration to pre-lay

62,908 feet of submerged pipeline from Ship Shoal to Whiskey Island is

42 days. Submerged pipeline will be installed prior to beach/dune fill

construction during the period of June - July 2012.

Containment Dike South (CDS) - Whiskey Island: The CDS separates the

beach/dune fill from the marsh fill and will be constructed concurrently with the

installation of the sediment pipelines and beach/dune fill. Construction of the

CDS is estimated to progress at 400 feet per day based on review of prior

projects. There is estimated to be 17,918 feet of CDS required for Whiskey

Island requiring 45 days for construction (June - August 2012).

Beach/Dune Fill: Dredge and fill activities for Whiskey Island beach/dune would

require the excavation and placement of 8,330,215 cubic yards (in-place) of sands

from Ship Shoal. This is calculated to take 10.7 months or 325 days. (July 2012 -

June 2013)

Sand Fencing - Whiskey Island: Sand fencing along the dune of Whiskey Island

is estimated to require 18,075 feet of materials and be installed at 900 feet/day.

Sand fencing installation would commence following beach/dune construction

and be completed in 20 days (June - July 2013).

Containment Dike North - Whiskey Island: The CDN separates the marsh fill

from the backbay and will be constructed concurrently with the relocation of the

sediment pipelines. There is estimated to be 7,370 feet of CDN required for

Whiskey Island requiring 19 days for construction (March - May 2013).


11-12

Pipeline Relocations

o Pickup Submerged Pipeline: Following beach/dune construction the

submerged pipeline must be relocated from Ship Shoal borrow area to

Whiskey Island TE-50 borrow area 3A. This requires the removal of

62,908 feet of submerged pipeline from Ship Shoal to Whiskey Island. At

a pace of 1,500 feet per day, it is anticipated to take 42 days to relocate the

submerged pipeline. (June - July 2013)

o Pre-lay Submerged Pipeline: Installation of 34,288 feet of submerged

pipeline from Whiskey Island TE-50 borrow area 3A to Whiskey Island.

At a pace of 1,500 feet per day, it is anticipated to take 23 days to reinstall the submerged pipeline. (July - August 2013)

Marsh Fill: Dredge and fill activities for Whiskey Island marsh would require the

excavation and placement of 579,724 cubic yards (in-place) of mud/silt from

Whiskey Island TE-50 borrow area 3A. This is calculated to take 0.8 months or

23 days. (August - September 2013)

Pickup of Pipeline

o Pickup Shore Pipeline: Following fill activities on the island 11,071 feet of

shore pipeline will be broken down and readied for transport. These

activities are anticipated to require 22 days. (September - October 2013)

o Pickup Submerged Pipeline: Following fill activities on the island 34,288

feet of shore pipeline will be broken down and readied for transport. These

activities are anticipated to require 23 days. (September - October 2013)

Demobilization:

o Demobilize Pipeline: Demobilization of the sediment pipeline is

anticipated to take 14 days. (October 2013)

o Demobilize Equipment and Crews: Demobilization of the shore equipment

and crews is anticipated to take 8 days. (October 2013)

o Demobilize Dredge: Demobilization of the dredge is anticipated to take 14

days. (October 2013)

Vegetative Plantings:

o Plantings - TY1: Aerial Seeding and Dune/Swale planting will take place

during the appropriate season in Target Year 1. (Anticipated time April -

May 2014)

o Plantings - TY2: Woody Species and 50% Marsh Fill plantings will take

place during the appropriate season in Target Year 2. (Anticipated time

April - May 2015)

o Plantings - TY3: Remaining 50% Marsh Fill plantings will take place

during the appropriate season in Target Year 3. (Anticipated time April -

May 2016)


11-13

L11.2.4 First Component of Construction Renourishment Construction

Schedule

The PED process for the renourishments shall begin prior to the designated TYs (TY20

and TY40) for renourishment.

First Component of Construction - Renourishment at TY20

Renourishment at TY20 will follow the same schedule as the initial construction with the

exceptions that it will not involve marsh fill construction or marsh fill vegetative

planting. Dune/swale aerial seeding and planting should occur in TY21 and TY22. The

volume of sediment required will be that needed to restore the geomorphologic form and

ecological function, plus accounting for five years of background erosion/land loss.

First Component of Construction - Renourishment at TY40

Renourishment at TY40 will follow the same schedule as the initial construction with the

exceptions that it will not involve marsh fill construction or marsh fill vegetative

planting. Dune/swale aerial seeding and planting should occur in TY41 and TY42. The

volume of sediment required will be that needed to restore the geomorphologic form and

ecological function of Whiskey Island.

See Section L11.3 for details of AMP full schedule durations.

L11.3 ADAPTIVE MANAGEMENT AND MONITORING PLAN SCHEDULE

The AMP program setup and initial monitoring is anticipated to begin at the start of PED

in December 2010 and continue through the end of construction for the initial

restorations. The implementation of the AMP and post construction monitoring is

anticipated to begin at the completion of the initial restorations and run for ten (10) years

if required.


12-1

L12. VALUE ENGINEERING REPORT

L12.1 INTRODUCTION

This section is a summary of and excerpts from the Value Engineering Study (VE)

Report as it pertains to the LCA Terrebonne Basin Barrier Shoreline Restoration Study.

Complete details can be found in the final report titled Value Engineering Study Report,

Terrebonne Basin Barrier Shoreline Restoration, Multipurpose Operation of Houma

Navigation Lock, Convey Atchafalaya River Water to Northern Terrebonne Marshes

prepared by Value Management Strategies, Inc (VMS, 2009).

The VE study report summarized the events of the VE workshop conducted May 5  8,

2009 for the U.S. Army Corps of Engineers (USACE), New Orleans District, by VMS.

The subject of the study were the LCA TBBSR, Houma Navigation Lock Operations, and

Convey Atchafalaya River Water to Northern Terrebonne Marshes Studies.

This study was conducted at the Feasibility Scoping Report/Preliminary Draft EIS, an

early stage of Study development, and as such was at the beginning of plan formulation.

L12.2 VALUE ENGINEERING PROCESS

VE is a strictly adhered to process that follows specific steps and procedures. The

specific steps in the VE process are as follows:

Step 1: Preparation  Developing a basic understanding of the client/user needs and

requirements, specific goals, and current costs, with an agreement on the scope of the

study.

Step 2: Information  Information is gathered prior to and during the study, and is

reviewed and discussed with the team. A summary of Study constraints, critical

issues, and observations from field inspection can be found in the Study Analysis

section.

Step 3: Function Analysis  Defines the functions of the Study through an organized

use of the Function Analysis System Technique (FAST) diagram that shows how the

functions are related to one another.

Step 4: Speculation  Also known as creativity, it is the application of brainstorming

techniques to develop a large quantity of ideas rather than focusing on the quality of

ideas. A complete list of workshop ideas can be found in the Idea Evaluation section.

Step 5: Evaluation  Reduces the large quantity of ideas to a few high quality ideas.

Step 6: Development  The concepts identified in the evaluation phase are developed

into specific VE alternatives that have been technically validated and quantified as

much as possible.


12-2

Step 7: Report  Containing the VE teams recommendations and a presentation to

the project stakeholders to receive their approval of these recommendations.

Step 8: Implement and Audit  Tracking the implementation of alternatives and

auditing the results measures the effectiveness of the VE effort.

L12.3 VALUE ENGINEERING ALTERNATIVE CONCEPTS

The table that follows summarizes all of the alternative concepts developed by the VE

team. The items in bold text were identified by the VE team as items of particular note

and key recommended strategies for the PDT to consider.

Table L12-1. Summary of Value Engineering Alternative Concepts

(Terrebonne Basin and General/Plan Formulation Only)

Number Description

LCA Terrebonne Basin Barrier Shoreline Restoration Study

T-1 Install inverted breakwaters and use excavated material to construct or

replenish back marsh

T-2 Obtain a clear definition of the Study objectives regarding sustainability

T-3 Establish permanent trust fund for renourishment costs

T-4 Construct a permanent pipeline from Ship Shoal to the east end of East

Timbalier Island

T-5 Conduct offshore sediment analysis to identify alternative sources of barrier

island renourishment sediment

T-6 Consider windpowered fixed dredged sediment supply

T-7

Use Bureau of Ocean Energy Management, Regulation, and

Enforcement (BOEMRE) to regulate Ship Shoal quantities to various

projects needing sediment

T-8 Consider coastal geomorphic processes for sediment placement

T-9 Utilize sand recycling/backpassing for barrier island nourishment

T-10

Fix barrier islands in their current location, eliminating/minimizing

island rollover, by incorporating a hard core (e.g., buried sandfilled

Geotubes, revetments) or allow surface armoring (e.g., revetments, rock,

concrete)

T-11 Construct groins and/or breakwaters with pre-filled sediment

T-12 Construct new barrier island chain closer to new shoreline

T-13 Establish an environmental dredging fleet

T-14 Prioritize Study components based on marsh loss factors

T-15 Add Plan Strategy that addresses habitat needs in excess of budgetary

limitations

T-16 Implement oil/gas industry outreach program regarding future sediment

management

T-17 Change the term nonstructural in Study documents to soft structural

General / Plan Formulation


12-3

Number Description

G-1 Develop Plan Strategies that account for higher levels of global sea level

rise

G-2 Develop a seasonal freshwater management plan

G-3 Create a Federal advisory committee

G-4

Identify and incorporate the effects of subsidence from fluid withdrawal in

the Study analysis and design; utilize water injection to minimize the impacts

of fluid withdrawal-induced subsidence

G-5 Consider alternate procurement methods for construction

L12.3.1 Alternative Concept Descriptions - LCA Terrebonne Basin

Barrier Shoreline Restoration

T-1 Install Inverted Breakwaters and Use Excavated Material to Construct or

Replenish Back Marsh

This Study Area faces a severe shortage of suitable material for island/dune construction

as well as the back marsh. A potential good source of back marsh material may exist just

offshore of the barrier islands on the GOM side. This material can easily be dredged and

placed on the land side of the island as the base for the back marsh. With this excavation

comes another advantage, the construction of an inverted breakwater on the GOM side in

front of the island.

The construction of inverted breakwaters parallel to the beach is a simple concept that

could prove to be very cost effective as well as physically effective for normal wave

activity. They could even be constructed in tandem with offshore shoals. The concept is

depicted in Figure L21-1.

Figure L12-1. Inverted Breakwater Concept

The argument against inverted breakwaters is that the inverted breakwaters may trap

some of the sand eroding from the beach, and thus negatively impact the littoral drift.

However, the current littoral drift carries minimal sediment so the effect downdrift should

also be minimal.

The advantage of this approach is the potential for obtaining sediment close to points of

placement at a lower cost to the restoration. In addition, the initial wave heights will be

diminished by the inverted breakwater, reducing impact energy along the shoreline and


12-4

allowing more time for stabilization of plantings. Over time it is probable that movement

of sediment will fill in the inverted breakwater because, at this location, there is a

decrease in wave energy and the trench acts as a sediment trap. But this could be seen as

a benefit as these trenches would become excellent locations for material needed in future

maintenance dredging to renourish and sustain the program.

A paper published in the Journal of Waterway, Port, Coastal, and Ocean Engineering

(January/February 1996) entitled MultiPit Breakwaters by William G. McDougal, A.

Neil Williams, and Keizo Furukawa assessed the benefits of a submarine depression used

as a breakwater. They found that the appropriate selection of depression (pit) dimensions

and placement may lead to a significant reduction in wave height behind these structures.

The shadow region behind the pits can reduce the wave heights by 10% to 20% of the

incident wave height. This paper provides guidance on the selection of pit (inverted

breakwater) geometries and placement for optimal breakwater performance. These

features would not be very effective in reducing significant storm surges, in the same

manner that offshore rock breakwaters would not be effective either. Further modeling

and/or test reaches are recommended to assess their applicability to the Study.

T-2 Obtain a Clear Definition of the Study Objectives Regarding Sustainability

The first environmental operating principle of the USACE states that the USACE should,

Strive to achieve environmental sustainability, and recognize that an environment

maintained in a healthy, diverse, and sustainable condition is necessary to support life.

The sixth item listed in the 12 Actions for Change indicates that the USACE should

focus on sustainability. It is clear from these principles and actions that sustainability is

important to the USACE and, consequently, should be incorporated into USACE

activities. However, the April 2009 Feasibility Scoping Meeting Report (FSMR) does not

contain any mention of how sustainability will be considered in plan formulation.

Moreover, there is no definition of sustainability provided in the FSMR. A clear

definition of sustainability is needed in order to make sustainability a meaningful Study

objective.

Such an objective may be established as follows:

Sustainable with resources within the LCA up to the Year 2100 based on a range

in relative sea level rise (e.g., extrapolation of historical rates of sea level rise,

accelerated rate of sea level rise per NRClow I, and accelerated rate of sea level

rise per NRChigh III) no matter what the cost.

T-3 Establish Permanent Trust Fund for Renourishment Costs

Eustatic SLR at the highest rates combined with subsidence could be a net rise of nearly 6

feet by Year 2100 and thus inundating the Study Area. If the LCA program is not

cancelled by Congress for these reasons, then an alternative concept requires repeated fill

and restoration efforts to keep pace with both Eustatic SLR rise and subsidence. This is

not a sustainable condition, but demands continuous repeated beach renourishment and


12-5

marsh platform fill in perpetuity. Placing fill at the rate that equals the combined faster

rate of Eustatic SLR rate based on this current science, and the known subsidence rates,

in perpetuity will be vital for restoration success. Consequently, episodic (e.g., every five

years) marsh platform fill and barrier island sand nourishment is essential for ecological

restoration success. Renourishment needs based on just the NER process using cost

effective incremental cost analysis justification cannot provide for perpetual ecological

needs.

Congress typically chooses not to undertake financial obligations requiring future funding

for perpetual costs. But Congress may appropriate funds to establish a permanent trust

fund and the interest accrued would provide for perpetual costs. While such costs may be

included as O&M costs provided by State, not Federal, funding, then only State assets,

not national assets, are accessible. However, support is growing in Congress for certain

permanent trust funds, for residential housing for example, which would build on

successful trust fund models by States and tribes. By far the largest is the $26 billion

Alaska Permanent Fund.

A possible example for a beach renourishment permanent trust fund: A multivariant

analysis of the costs to assure dredging and placement of sand from Ship Shoal to the

Terrebonne Basin barrier islands based on the above various rates of Eustatic SLR rise is

performed to determine the projected range of perpetual funding needed. If, for example,

an annual beach renourishment cost of $5 million is required to keep pace with the

accelerated rate of Eustatic SLR, then a permanent beach renourishment trust fund of

$166 million yielding 3% annually would be needed. (Should this trust fund yield exceed

renourishment requirements, the trust fund may grow or alternatively annual net excess

can be returned to the U.S. Treasury.)

References:

NOAA, Sea Levels Online.

http://tidesandcurrents.noaa.gov/sltrends/sltrends.shtml

T-4 Construct a Permanent Pipeline from Ship Shoal to the East End of East

Timbalier Island

One of the potential methods for barrier island construction and renourishment being

considered by the PDT is to create feeder beaches that may erode into the littoral drift

transferring sand to be deposited on barrier islands to the west. The primary location for

such a feeder beach would be the east end of East Timbalier Island. Typically, this

would involve periodically bringing in a dredge to Ship Shoal, laying a pipeline, and

transferring sand to the feeder beach.

If the PDT determines that there is benefit to identifying a permanent location for

deposition of renourishment sand at East Timbalier Island, it may be possible to lay a

permanent pipeline for the dredge to hook up to. The pipeline could terminate on land,

though this may create an issue with excessive accumulation of sand in a small area that

might plug the pipe and prevent full deposition of the desired volume of sand. It may be


12-6

preferable to terminate the sand within the littoral drift current itself rather than on dry

land so that the sand begins its journey to the west immediately after it exits the pipe. A

key concern would be locating the pipeline to avoid or minimize impacts to existing oil

and gas facilities located between Ship Shoal and East Timbalier Island.

A further refinement of this idea would be to construct a permanent dredging plant at

Ship Shoal to feed this pipeline. This dredge could be powered by green technologies

(wind, solar) as discussed in another proposal.

T-5 Conduct Offshore Sediment Analysis to Identify Alternative Sources of Barrier

Island Renourishment Sediment

The PDT has indicated that a major constraint in achieving the Study objectives is the

availability of suitable sediment to restore and maintain the barrier islands. Although

Ship Shoal was identified as a sediment source with known reserves of sand, there are

numerous projects in the LCA program that are planning to utilize these sediment

resources. In addition, Ship Shoal is between 50 and 100 miles from the barrier islands

depending on the exact location within Ship Shoal and the island that is being restored

with sand from this sediment source. Consequently, the cost of restoring the islands could

be reduced significantly if alternative sediment sources closer to the islands were utilized

for restoration activities. These sources may consist of sand layers located beneath the top

sections of nearshore bottoms.

It is suggested that an offshore sediment source investigation be conducted to identify

alternative sources of barrier island restoration and nourishment sediment. The

investigation would focus on the area in the immediate vicinity of the islands and on the

side towards the GOM. It might be possible to tap into the oil/gas industry for geological

information (e.g., seismic recordings, geological logs, and sediment borings) to assist in

conducting this investigation, thereby reducing the costs of the investigation. In addition,

this recommendation could be used to suggest funding for the BOEMRE to conduct this

investigation for the purpose of mapping the sediment resources in the area since

BOEMRE is the Federal agency responsible for managing these offshore resources.

T-6 Consider Wind-Powered Fixed Dredged Sediment Supply

This alternative concept involves the permanent placement of a cutter head pipeline

dredge at Ship Shoal with the pipeline terminus on East Timbalier Island. Sand deposited

here subtidally is expected to accrete to the barrier islands by longshore displacement.

Two booster pumps (either kinetic or positive displacement) are needed to supplement

the dredge pump due to the distance the sand slurry can be pumped without pipe

sedimentation. Two booster pumps would be installed to form a series spaced equidistant

from the dredge site to the disposal site. A displacement booster pump used in

combination with a centrifugal dredge pump would require a booster pump holding

facility because it is difficult to match positive displacement pumping rates to centrifugal

pumping rates.


12-7

Offshore Louisiana has potential for wind energy development according to two reports

prepared for the Department of Energy in 1979. Offshore areas west of the Mississippi

River offer a high Class 3/low Class 4 wind energy resource. (Class 7 being the

maximum and Class 3 is the threshold for feasible wind power development.) In 2005,

the Louisiana legislature approved authority for the State Mineral Board to lease State

lands and water bottoms (i.e., areas within three miles of shore) for the production of

wind energy.

To power these slurry pumps, three 1.5 MW capacity wind turbines and towers would be

installed: one at the Ship Shoal cutterhead and two others to power the booster pumps.

Wind power supply is interruptible. Cut in wind speed, when power is produced, begins

at 3.5 m/s (8.4 mph). Because the windpowered electric pumps would shut down when

the wind is below the cut in speed, a flap valve at each booster station would be installed

to drain the slurry to prevent sediment build up in the pipe.

The installed price for each 1.5 MW wind turbine and tower is estimated at $17.5 million

according to the Danish Wind Industry Association. General Electric produced over

10,000 1.5 MW capacity wind turbines successfully operating since 1996 and are

manufactured at GEs Pensacola, Florida plant.

T-7 Use BOEMRE to Regulate Ship Shoal Quantities to Various Projects Needing

Sediment

The proposed concept is to use the BOEMRE to regulate the use of Ship Shoal sediments

for use by various projects, in particular coastal barrier island restoration. Included in the

idea is the thought to have BOEMRE evaluate the actual quantities of available sediment

at Ship Shoal and determine appropriate locations for its use.

Background

Following a request by the USACE to be a Cooperating Agency in the LCA Barataria

Basin Barrier Shoreline Restoration, the BOEMRE has been working with the USACE

and other Federal and State natural resource agencies regarding the use of Ship Shoal and

other sand bodies under their jurisdiction for use as sand sources for coastal restoration

projects. Working as a Cooperating Agency for the LCA Barataria Basin Barrier

Shoreline Restoration, the BOEMRE determined the need for intensive coordination and

management of offshore sand resources for use in coastal Louisiana restoration projects.

In May 2003, Mr. Barry Drucker with the BOEMRE established the Louisiana Sand

Management Working Group (LASMWG) with the intent and purpose of bringing

together various Federal and State natural resource agencies, as well as potential sand

resource users. S. Jeffress Williams, USGS (Coastal and Marine Geology Program, 384

Woods Hole Rd., Woods Hole, MA 02543, email: jwilliams@usgs.gov) provided a

compelling summary of the problems and opportunities at the meeting:

Need for longterm sand requirements: Use of offshore sand for nourishment and

coastal restoration in Louisiana, as well as many other regions, has longer term

implications than just 20 to 30 years. The USACE projects are typically


12-8

authorized for 50 years. For several projects suitable and economical sand

resources have not been identified for 50 years of initial fill and periodic O&M

fills. In my judgment, we need longer term planning for compiling sand needs. At

minimum 50 years, 100 years is best.

Need for sediment database/Seafloor maps: For Louisiana in particular, a great

deal of data and information is available from very disparate sources on sand

body location, sand quality, and quantity. What is needed is a comprehensive

computerbased sediment database. The usSEABEDsystem is one start in this

direction, but it needs further development to incorporate subbottom data, i.e.,

cores, borings, and seismic. Also, at least for premier sand bodies like Ship Shoal,

Tiger Shoal, etc., we need complete map coverage of the seafloor using digital

mosaic sidescan and multibeam technologies that have recently become

available. Such base maps are critical for not only accurately delineating the sand

bodies, but also important for mapping essential fish habitats and infrastructure to

avoid, such as pipelines.

Permit streamlining: Plans for large scale barrier nourishment are well advanced

in Louisiana, potentially requiring ~100 CY meters of sand. An efficient

permitting process by the USACE and BOEMRE needs to be in place.

Science studies/monitoring: Important questions arise on sediment transport

processes associated with dredging and nourishment, such as: What is the

traditional engineering "closeout depth" for a particular coast and how close to

shore can you dredge without exacerbating erosion of the adjacent coast? What is

the importance of ebbtide shoal sediments for the Louisiana sediment budget and

can they be mined without causing downdrift erosion? What is the optimum

spatial and temporal design for dredging so as to minimize environmental harm?

How long do dredge holes remain open? What are their short and long-term

effects on marine habitats, wave refraction, etc.?

In May 2003, the BOEMRE provided in the Federal Register a notice to prepare a

multiproject environmental assessment to evaluate the potential environmental impacts

associated with the removal of sand resources from Ship Shoal. Meetings were conducted

over the ensuing years with BOEMRE funding scientific efforts to investigate the

potential impacts associated with removal of sand resources from Ship Shoal.

Implications for Creative Idea:

The BOEMRE is the regulatory agency with jurisdiction to manage the Ship Shoal and

other offshore Federal sand bodies. They have been conducting investigations over the

past several years. There have been several studies funded by the BOEMRE that have

determined the extent of sand and other mineral resources on Ship Shoal. The BOEMRE

has funded and will likely continue to fund studies regarding potential impacts of

removing these sand resources from Ship Shoal on aquatic organisms, as well as on wave

dynamics. However, BOEMRE does have authority to make decisions on suitability or

priority of sand use.


12-9

VE Alternative followup:

In June 2007, BOEMRE sent a letter to all stakeholders (Federal, State, and other)

requesting information on potential projects using outer continental shelf (OCS) sand and

gravel resources in the next five years. Based upon BOEMRE resources and stakeholders'

responses regarding project timelines, a maximum of two projects per quarter were

scheduled.

Most recently, BOEMRE sent another request in April 2009 to update the calendar;

responses were due June 1, 2009. Their intent is to publish the responses in the Federal

Register in the third quarter of 2009. It is anticipated that BOEMRE will continue to

schedule a maximum of two projects per quarter.

T-8 Consider Coastal Geomorphic Processes for Sediment Placement

The configuration and manner in which sediment will be placed on the barrier islands

was not presented in the April 2009 FSMR. It appears that the PDT is leaning towards

placement of most sediment (sand on the GOM side and mud on the bay side) on the

downcoast side of the islands, which is the western end of each island. This preliminary

decision is apparently based on the fact that the longshore transport moves sediment from

east to west. Likewise, from a crossshore standpoint it does not appear that much

consideration has been given yet to how the sediment would be placed from the beach

across the dune and into the backbay marsh. It might be possible to increase the

longevity of the placed sediment by considering the coastal geomorphic processes in

developing and/or refining the configuration and manner of sediment placement.

Instead of placing sand in equal amounts along the entire length of the island or in larger

volumes at the western end of each island, the PDT should consider constructing the east

end of each island wider than the west end. Utilizing this configuration for the beach

restoration and nourishment activities would allow the eastern beach area to serve as a

feeder beach providing a sediment source to nourish downcoast (western) beaches as the

longshore transport moves the sand from east to west. Prior to implementation, a coastal

processes analysis should be conducted to determine the maximum beach width in each

area to avoid overbuilding the beach in the eastern portions of each island. An overbuilt

beach could push the sand into deeper waters and/or result in overly steep beach slopes,

both of which could increase the rate of erosion.

Another consideration in the placement of sediment for island restoration is the aspect

ratio of each barrier island. The aspect ratio is the length of each island divided by the

width and it can be calculated as a mean or at regular intervals (e.g., every quarter mile)

along the entire length of each island. There has been some research conducted to

estimate the optimum aspect ratio for the barrier islands and this information should be

considered in the development of sediment placement configurations (volumes and

locations).


12-10

T-9 Utilize Sand Recycling/Backpassing for Barrier Island Nourishment

Beach restoration and beach nourishment are presented in the April 2009 FSMR as two

management measures that will be carried forward for future consideration in the

formulation of Study alternatives. Beach restoration is defined in the FSMR as the

(initial) placement of beachsuitable sediment (sand) within the beach profile from the

dune out to the depth of closure, while beach nourishment is defined as the periodic

placement of sand in the same location. Beach restoration basically restores the shoreline

and beach to historical conditions, while beach nourishment keeps pace with future

erosion to maintain the restored condition. Ongoing beach nourishment activities will

require the identification and dredging of additional sources of sand in the future. Based

on existing information and data, sand is already limited in availability and there is a lot

of demand for that sand for this Study as well as other projects in the LCA program.

Therefore, the retention and efficient use of existing and future sand resources will be an

important factor in costeffectively meeting Study objectives.

One way to make more efficient use of existing and future sand resources is to utilize

sand recycling/backpassing to replace and/or augment beach nourishment activities. In

the Terrebonne Basin barrier islands, the net longshore transport is from east to west,

meaning that sand is driven by the waves from east to west. Sand recycling would consist

of dredging sand at the western end of the barrier islands and placing it on the eastern

end. This would help reduce the quantity of new sand needed for future nourishment

activities. The effectiveness of sand recycling can be improved through the construction

of terminal groins or breakwaters at the downcoast end of the barrier islands to capture as

much sand as possible before it is lost to the bay area and/or GOM. Prior to

implementation, coastal processes analyses should be conducted to make sure that sand

from an upcoast island (i.e., to the east) is not providing a substantial source of sand to a

downcoast island, otherwise the sand recycling program might result in increased erosion

to the downcoast barrier island. Sand recycling has been used with success along

Peninsula Beach, which is located in Long Beach, California.

T-10 Fix Barrier Islands in Their Current Location, Eliminating/Minimizing Island

Rollover, By Incorporating a Hard Core (e.g., Buried Sand-Filled Geotubes,

Revetments) or Allow Surface Armoring (e.g., Revetments, Rock, Concrete)

The natural geomorphic development of barrier islands is to allow them to rollover where

the dune field progresses landward overriding the back marsh as the beach face erodes.

This is currently the preferred design as presented by the PDT. In order for this approach

to be successful, periodic renourishment (typically every five years) is required over the

50year period of analysis to maintain both the barrier island and the back marsh.

However, the current Study plan and budget only allows for a single renourishment after

about five years, which means the sustainability of the Study is in doubt.

An alternative approach is to fix the islands in place and minimize the amount of

renourishment required. This is not a natural geomorphic process for barrier islands as

it limits rollover and migration of the barrier island landward. However, there are


12-11

agencies in the State, as well as members of the general public, who would prefer this

approach as a more positive means of providing storm surge and salinity intrusion

protection. Fixing the location of the islands with a corresponding reduction of

renourishment needs may improve sustainability within the available budget for the

Study. It would also reduce the amount of material needed, which is a considerable

general Study concern.

One alternative installs a buried hardscape that draws a lineinthesand on the

shoreline. The sandfilled Geotube (using sand already earmarked for beach and dune

restoration) would resist erosion of sand along with storm surgerelated breaches in a

more costeffective manner than, say, offshore breakwaters. In most cases these Geotubes

can replace the offshore breakwaters, or be used in tandem with the breakwaters (such as

inverted breakwaters proposed above) in critical areas.

Since the Geotubes are not exposed most of the time, they will not experience

deterioration from sunlight or vandalism. If damage to the Geotubes occurs from storm

surge activity, they can be replaced or repaired. Erosion of the sand in front of the

Geotubes and on top will likely occur over time requiring renourishment of the dunes

approximately every ten years. A sketch of this concept is shown in Figure L12-2:

Figure L12-2. Geotube Incorporation in Beach Design Concept

In lieu of Geotubes, other hardened materials such as revetments or rock can be buried in

the core to increase the hardness of the island. Further, surface hardening can be

considered through the use of surface revetments, concrete, or rock; however, this

approach may not be preferred over the hardened core concept as it would take away

from the sand beach surface that may be preferred nesting areas for birds. In addition,

surface hardening would be considered to be less aesthetic than exposed sand surfaces,

and would be less capable of supporting stabilizing vegetation.

T-11 Construct Groins and/or Breakwaters with Pre-filled Sediment

The use of groins and breakwaters to trap sand on the barrier islands were identified as

potential management measures to be carried forward through the plan formulation

phase. Based on the information presented in the April 2009 FSMR, it appears that groins

and breakwaters would be implemented without the use of pre-fill. The implementation

of groins and breakwaters without pre-fill can lead to erosion of adjacent shorelines and

beaches as indicated in the FSMR. This erosion is caused by the trapping (or retention) of

sand in the fillet of the groins, as well as the salient (or tombolo if the salient touches the

shoreline) of the breakwaters.


12-12

The addition of pre-fill should be considered to address the potential impact of erosion

attributed to the implementation of groins and breakwaters. For groins, the use of pre-fill

would entail estimating the volume of sand that would be trapped in the fillet and then

placing this volume of sand in the fillet as part of the initial groin construction project. In

the case of the breakwaters, the use of pre-fill would consist of estimating the volume of

sand that would be trapped in the salient and then placing that volume of sand in the

salient as part of the initial breakwater construction project. The use of pre-fill mitigates

for impacts to adjacent beaches while the retention structure (i.e., groin or breakwater)

provides a wider, more stable beach. Prior to implementation of pre-fill for a breakwater,

a coastal processes analysis should be conducted to assess the potential impact of the

salient itself on longshore transport.

T-12 Construct New Barrier Island Chain Closer to New Shoreline

There is high probability that maintaining the existing barrier islands beyond the 50year

period of anaylsis will not be possible due primarily to increasing rates of sea level rise,

future subsidence, and resources constraints (e.g., sediment supply and funding). Given

the value of the habitat on the islands, as well as the important role these islands play in

protecting bayside resources, it still makes sense to expend resources in restoring and

maintaining the islands from now and into the immediate future (e.g., 50 years).

However, it also makes sense to begin thinking now about the longterm sustainability of

the entire ecosystem in the LCA.

It is suggested that consideration be given to the design and construction of a new barrier

island chain. This would include the identification of a new fallback shoreline that

would be used to guide the location of the new barrier island chain. This new shoreline

and barrier island chain would form the second line of defense, with the first line of

defense being the restoration and protection of the existing barrier islands. The new

barrier island chain could be constructed in areas of the existing LCA that are relatively

high in elevation and free of oil and gas wells and pipelines to minimize construction

costs associated with fill placement and construction access. In addition, this strategy

could be implemented through an adaptive management framework such that lessons

learned from restoration and maintenance of the existing barrier islands could be used to

improve the design, construction, and maintenance of the new barrier island chain.

T-13 Establish an Environmental Dredging Fleet

The amount of sediment needed to renourish the barrier island system will far exceed the

available dredge fleet in and beyond the region. While private industry will respond to

this need by manufacturing additional dredges as projects progress, it is likely that such

plant development will severely lag demand. Private industry will not likely produce

more than is needed at any given period, as they will perceive a risk of over supplying

intermediate need. Such projected constant shortages will likely limit bid completion and

raise prices substantially.


12-13

A possible means of avoiding this problem may be government partnerships with private

industry to fabricate new dredges in advance of individual project need. For example, the

government could build the needed fleet and lease the equipment to industry; the

government could finance industry to build their fleet; or industry could build the fleet on

their own and lease equipment to the government. There are a number of

lease/purchase and other innovative procurement options that balance risk and optimize

financial advantages between the government and industry. In general, the government

can secure capital at relatively low cost and industry can take tax advantages of

ownership via depreciation deduction. Such advance fabrication of dredges could help in

achieving adequate resource supply to meet projected demand.

T-14 Prioritize Study Components Based on Marsh Loss Factors

The PDT indicated that some type of system would be needed to prioritize restoration

activities. However, it does not appear that such a system was developed or applied

during preparation of the information contained in the FSMR. The PDT was asked if an

estimate had been developed that represents the percentage of marsh loss due to the

various causes of erosion. For example, how much of every 100 acres of marsh loss is

attributed to sea level rise, fluid withdrawalinduced subsidence, sediment

compactioninduced subsidence, windwave erosion, storminduced erosion, vegetation

loss attributed to salinity changes, and herbivore activity. Note that a cursory review of

the figure in Attachment F of the April 2009 FSMR suggests a relationship between oil

and gas extraction (as represented by oil and gas wells) and marsh loss (as represented by

open water areas). It is important to develop an estimate of the importance of these

various loss factors because a primary stated objective of the barrier island restoration is

to protect and preserve the marsh to the north of the islands. If sea level rise and

fluidinduced subsidence are of equal or greater importance than windwave erosion and

storminduced erosion, then restoration of the barrier islands may not achieve this

objective.

One way to address this issue would be to conduct an analysis to determine the amount of

marsh loss attributed to sea level rise, fluid withdrawalinduced subsidence, sediment

compactioninduced subsidence, windwave erosion, storminduced erosion, vegetation

loss attributed to salinity changes, and herbivore activity. The results of this analysis

could then be used to prioritize Study components, thereby giving the PDT a planning

tool for the prioritization task that they will have to undertake. The results might also

suggest that it is not possible to meet some of the Study objectives or that the objectives

themselves need to be prioritized in order to select the appropriate restoration activities.

Concern about the possible findings of this analysis should not be used as a reason not to

conduct it since the results will merely inform the decision making process. For example,

even if the results indicate that sea level and/or subsidence are primary contributors to

marsh loss, it does not mean that barrier island restoration should not be implemented,

rather, it means that barrier island restoration would probably not be effective in meeting

the Study objective related to marsh protection from windwave erosion and

storminduced erosion.


12-14

T-15 Add Plan Strategy That Addresses Habitat Needs in Excess of Budgetary

Limitations

The Plan Strategies identified for the Study are intended to produce a full spectrum of

alternative plans as required by National Environmental Policy Act (NEPA) and USACE

planning guidance in ER 1105-2100. Alternative Plan Strategies were designed to be

significantly different from one another and to represent the entire range of solutions to

identified problems within the Study Area. This VE alternative concept is intended as a

check to the PDT that Plan Strategy E, increase of current configuration and functional

geomorphology, be the Plan Strategy that addresses habitat needs above and beyond the

budgetary limitations set by the Study authorization. During the NEPA alternative

evaluation process, this consideration is needed regardless if the funds will be available to

ever make the alternative feasible. If Plan Strategy E is not intended to satisfy this part of

the alternative evaluation, suggest developing an additional Plan Strategy that does

address the best case scenario regarding habitat creation and sustainment.

T-16 Implement Oil/Gas Industry Outreach Program Regarding Future Sediment

Management

The PDT indicated that the oil/gas industry (industry) might redistribute sediment placed

on the islands following restoration activities. The industry has a longstanding practice of

redistributing sediment to protect oil/gas infrastructure. For example, the industry

redistributes sediment via dredging to bury pipelines that have become exposed following

storm and hurricane activity. Consequently, the PDT expressed concern that the industry

would utilize the newly placed sediment for this purpose upon completion of restoration

activities, thereby decreasing the effectiveness of restoration activities and undermining

Study success.

An outreach program could be implemented to proactively address this issue. The

outreach program would explain the various restoration components to the industry. It

would include a description of the natural sediment processes and how those processes

would benefit the natural habitat and resources, as well as how those processes would

benefit the industry. A description of acceptable sediment management practices would

be included in the outreach program to minimize negative practices and maximize

positive practices since it might be possible to work with the industry to help maintain

and/or improve the islands upon completion of restoration activities. Finally, the outreach

program would have to be developed in careful consideration of the target group that is to

receive the information to make sure the right people in the industry are getting the

message and that it is tailored to those people. This will help ensure that the right

message is getting to the right people.

T-17 Change the Term Non-Structural in Study Documents to Soft Structural

The Study documents uses the following definition of terms: A management measure is

a feature (a structural element that requires construction or assembly on-site) or an

activity (a non-structural action) that can be combined with other management measures


12-15

to form alternative plans. The term non-structural is commonly used in USACE flood

control and hurricane protection projects. It has a very specific meaning that includes

options such as flood proofing property, raising buildings above flood elevations,

purchasing property and/or relocating or removing the property from the area of risk, and

prohibition of further development in areas of risk. However, for this Study, the term is to

refer to restoration activities that include:

Dune restoration;

Marsh creation;

Beach restoration;

Beach nourishment;

Subtidal sediment placement;

Addition of sediment into near-shore environment to supplement littoral drift;

Beach closure;

Small marsh island construction on bayside for bird habitat;

Vegetative planting;

Herbivory control;

Biological bio-engineered oyster reefs;

Spit creation; and

Canal backfilling.

In order to avoid confusion with a generally accepted definition, the VE team

recommends that the term nonstructural, as used in the Study documents, be changed to

soft structural.

L12.3.2 Alternative Concept Descriptions - General / Plan Formulation

G-1 Develop Plan Strategies that Account for Much Higher Levels of Sea Rise

The purpose of this ecological restoration is to achieve a sustainable solution, but the

Study must respond to Relative SLR as the combined rates of subsidence and SLR. SLR

consists of two factors: 1) Eustatic rise due to density warming and 2) landbased glacial

melt rise. Eustatic sea level rise during the next 50 years is expected to be approximately

4 inches (IPCC 4th Assessment Report, 2007). The IPCC has not yet projected the

portion of SLR due to landbased glacial melt. Under the 2007 IPCC business as usual

scenario, Eustatic SLR is projected to be 0.75 feet to 1.5 feet by 2100. At that time, no

significant acceleration of SLR rise had been detected. New research published this year

indicates that SLR could be 3 to 4 feet by 2100, which is much higher than IPCC 2007

predictions (Niels Bohr Institute, published in the journal Climate Dynamics). The great

uncertainty in the rate of SLR regards how quickly the ice sheets on land will melt.

The subsidence rate in the Mississippi River delta planning area range from 1.0 to 3.5

feet by the year 2100. The Relative SLR (i.e., the Eustatic SLR rise and the deltas

subsidence rates) used for the LCA Program for the next 50 years are 1.3 to 2.6 feet, or

2.6 to 5.2 feet by the end of the century. Twentieth century rise in sea level from

observed data was about 1.8 mm/year as result of longterm response to the end of the


12-16

last ice age. Since 1992, however, satellite data have recorded an accelerated rate of SLR

of 3.0 mm/year, but this is not sufficiently long to determine if this rate will be prolonged

or is a shortterm change.

Benefits depend upon habitats maintained above sea level. Consequently, benefits beyond

the 50year period of analysis will be lost due to subsidence, SLR, and storminduced

habitat loss. Longterm melting of the Greenland ice sheet during subsequent centuries of

warming could result in complete melting over several thousand years, eventually

resulting in a SLR of 22 feet (7 meters).

As the rate of SLR in the future is unknown, the Study should develop specific Plan

Strategies that consider the range of possible future SLR rates, and check to see how

sensitive the Study design is to those different scenarios. Those future scenarios include:

A low level that is based on an extrapolation of the historic rate assumes SLR will

be linear in the future and will not accelerate;

A medium level that assumes SLR of 0.5 meters by 2100; and

A high level that assumes a greater future acceleration of SLR of 1.5 meters by

2100.

However, as noted above, current science projecting an accelerated rate of landbased

glacial melt has huge ramifications for Study viability or perpetual cost obligations.

Future SLR rate based on this science must wait on future work by the IPCC and U.S.

agencies to be completed by late 2009. This work is based on recent, and increased, rates

of observed SLR using satellite data, previous historic rates of sea level rise during past

glacial melt. Currently, work is underway by the USACE, NOAA, and USGS to

investigate the glacial melt contribution to future SLR.

G-2 Develop a Seasonal Freshwater Management Plan

Wetlands in the Study Area are deteriorating as a result of subsidence, lack of sediment

and nutrient deposition, saltwater intrusion and erosion. Deterioration will continue

unless action is taken to resolve the causative factors. Sustainable protection and

enhancement of the wetlands in the Study Area is dependent on providing a hydrologic

regime that minimizes the physiological stress to wetland vegetation.

Seasonal differences in the need for freshwater and nutrients, and the locations from

which freshwater can be recruited and distributed, should be optimized. For example, the

quantity of water that can be diverted from the Atchafalaya River to the Gulf Intracoastal

Waterway (GIWW) is somewhat limited due to infrastructure restrictions: traffic tunnel

in Houma and the Houma twin bridge abutments are two examples. Freshwater could

also be diverted into the GIWW system at the Harvey Lock and Algiers Lock. In

addition, freshwater is being diverted into Bayou Lafourche and Davis Pond. Each of

these is an individual site at which important resources can be introduced into the


12-17

wetlands; however, quality and quantity of freshwater could be enhanced with

coordination and planning treating these sources as a supply network.

Opportunities exist to naturalize the distribution of freshwater and, to a limited extent, the

deltaic forming sediments, improve distribution of freshwater, and to reduce the negative

impacts of GOM storm events. Seasonal GOM events have an intensive impact on the

remaining marsh areas. Opportunities exist through freshwater supply and distribution to

create a healthier marsh which will be more resistant to the normal range of events.

Cost to develop a management plan is minimal. Implementing the management plan

would likely require instrumentation and communication equipment.

G-3 Create Federal Advisory Committee

Public participation will be achieved through the NEPA process involving Federal and

State cooperating agencies, public review, and public and legislative hearings. This can

be augmented by developing a formal multiState committee. A Federal advisory

committee can be comprised of both government and nongovernmental stakeholders

along the Mississippi flyway, including Canada. The Federal Advisory Committee Act

(FACA, PL 42463) governs the establishment and behavior of Federal advisory

committees. There are now approximately 1,000 such committees. FACA was an attempt

by Congress to curtail the "lockerroom discussion" that had become prevalent in

administrative decisions and obligates transparency in the process.

For example, a Federal advisory committee may include the Missouri and Mississippi

State River Basin Commissions, and national and Canadian environmental organizations.

This would expand national interests to support Congressional intent, but will add

additional administrative burden to the USACE.

Example FACA Committee: The National Park Service, Georgia, Big Cypress National

Preserve OffRoad Vehicle (ORV) Advisory Committee.


12-18

G-4 Identify and Incorporate the Effects of Subsidence from Fluid Withdrawal in

the Study Analysis and Design; Utilize Water Injection to Minimize the Impacts of

Fluid Withdrawal-Induced Subsidence

The Principal of Effective Stress is a well known geotechnical engineering principal

applied to the consolidation of sediments and rock when there is a net change in

interstitial pressure in the system. Principally, this can be described as an increase in

stress between particles resulting from a reduction of pore fluid pressure that causes the

solid particles in the mass to move closer together. Once this consolidation of mass

occurs, it cannot be reversed. The reduction in fluid pressure happens when the fluids are

permanently removed from the system (that is, through the pumping or mining of

groundwater, oil, and gas). The consolidation of the solids produces general settlement

(or subsidence) of the ground surface.

Significant ground surface subsidence (sometime associated with fault development) as a

direct result of fluid withdrawal has been documented worldwide. Well known cases

exist in Houston, south central Arizona, North Las Vegas, and central California. In the

Long Beach, California area, from about 1920 to 1960, 29 feet of surface subsidence

occurred that was directly related to the removal of oil and gas.

The current documents do not fully address timedependent subsidence in the Study Area

due to oil and gas withdrawal, a process which is ongoing in the area. The amount of

such subsidence has not reportedly been documented to date. It is recommended that

surface subsidence due to fluid withdrawal in the Study Area, and its future impacts on

Study sustainability, be assessed and included in the Study design and documents.

There may be some visual evidence of a correlation of open water in the Study Area with

the concentrated location of oil wells. It could be interpreted that some of this open water

resulted, in part, from subsidence associated with the withdrawal of oil and gas from

these concentrated well areas. This visual comparison can be seen in the two maps below

(Figure L12-3, L12-4).


Figure L12-3. Approximate Areas of High Concentration of Oil & Gas Wells


Figure L12-4. Oil & Gas Infrastructure


12-21

As was mentioned above, from about 1920 to 1960 in the Long Beach, California area,

29 feet of surface subsidence occurred that was directly related to the removal of oil and

gas. Once this problem was identified, the petroleum industry elected to inject saltwater

into the subsurface to replace the withdrawn oil and gas as a mechanism of recharge that

would maintain the internal pressures, thus minimizing the change in effective stress. As

a result of this effort, additional subsidence has been limited to about 1 foot to date.

An added benefit of saltwater recharge has been the ability to increase the extraction of

petroleum from the reserve. Such recharge has become a standard practice in the

industry. If this is not already being done within the Study Area, the USACE is

encouraged to open discussions with the oil industry to see if the technique can be

implemented. This would reduce the amount of future subsidence due to fluid

withdrawal, extending the life of the Study and its sustainability.

G-5 Consider Alternate Procurement Methods for Construction

Given the complexities associated with identifying sources of material for renourishment

of the barrier islands, transport and placement of the material, and preservation of the

material, as well as limited specialized contractor availability, use of alternate

procurement methods should be considered. Examples of some of these methods include

CMatRisk and using Habitat Units as the pay items.

CMatRisk procurement, also known as Integrated DesignBidBuild or Earlier

Contractor Involvement, involves selecting a contractor and separate designer during the

design phase. Both parties work together under separate contracts with the government

with the objective of developing a design that is most efficient. The government then

negotiates and awards construction packages to the contractor. If negotiations are not

successful, the government reserves the option to bid the work on the construction open

market.

The process calls for the selection of a construction contractor (based on qualifications

only) early in the design phase. This contractor and the designer collaborate in

developing a design most suitable for the specific contractor while meeting all

performance requirements (such as maximizing the number of Habitat Units created). In

this arrangement, the government has the option to either negotiate a subsequent

construction price with the previously selected contractor or bid the job on the open

market. Such a procurement plan would help assure a constructible design that meets the

relatively complex requirements of this Study.


12-22

L12.4 STUDY ANALYSIS

Key Study Factors

The first day of the study included meetings with the Study stakeholders. The following

summarizes key Study issues and concerns identified during these sessions.

Project Issues

The following are some of the issues and concerns associated with the LCA TBBSR

Study:

Lack of sediment for barrier island renourishment. The demand for sediment from

various projects exceeds the supply at Ship Shoal;

Study authorization requires signed Chiefs Report by December 2010;

There is a limit to the number of dredges available to supply sediment for barrier

island renourishment;

Absolute sea level rise threatens the restorations justification and sustainment;

Key navigation routes through the Study Area limits must be maintained; and

Authorized funds do not provide for future renourishment requirements;

Function Analysis / Fast Diagram

Function analysis was performed and a FAST Diagram was produced, which revealed the

key functional relationships for the Study. This analysis provided a greater understanding

and how the Study objectives and specific activities are related.


LCA Terrebonne Basin Barrier Shoreline Study FAST Diagram

(Adapted from VMS, 2009)

Restore /

Protect Habitat

Reduce Storm

Damage

Create Land

Prevent Loss

Restore Land

Forms

Re-Nourish

System

d

Reduce Erosion

Dissipate Wave

Energy

Manage Tidal

Forces

Restore Beaches

Restore Dunes

Restore BackMarsh

Backfill Canals

Add Sediment

Preserve

Environment

Protect

Infrastructure

HOW? WHY?

Place Dredge

Material

(Feeder

Location)

Transport

Material

Place Rock

Install

Vegetation

Detail

Activities

Scope

Line

Scope

Line

Maintain

Navigation

All Time

Functions


12-24

L12.5 IDEA EVALUATION

L12.5.1 Introduction

All of the ideas generated by the VE team were recorded and evaluated with Studyspecific attributes applied to each idea to ensure an objective evaluation.

L12.5.2 Performance Attributes

Performance attributes represent those aspects of a Studys scope and schedule that may

possess a range of potential values (as opposed to performance requirements which

represent essential, non-discretionary aspects). The VE team developed the following list

of performance attributes to act as criteria for considering the value potential of the

creative ideas:

Coordination with natural/coastal processes. Includes sustainability of barrier

island system;

Functionality of habitat. Includes acres of habitat and quality of habitat;

Degree of protection to interior marsh; and

Schedule.

L12.5.3 Evaluation Process

The VE team, as a group, generated and evaluated ideas on how to best perform the

various major components or functions of the Study. The goal of the evaluation was to

select the best ideas that would produce a high level of performance at an acceptable

level of cost. The evaluation used the key criteria listed above and the function analysis

performed by the VE team. Given the relatively early level of Study development at the

time of the VE study (i.e., no original design), the team evaluated each of the ideas with

respect to each of the key evaluative criteria to determine whether it was better than,

equal to, or worse than the other feasible alternatives. The team then reached a consensus

on the ideas development status. Readers are encouraged to reconsider all ideas

generated by the VE team, as previously rejected ideas may prove to be feasible as the

Study development proceeds beyond the scope of the VE study.

L12.5.4 Idea Evaluation

All of the ideas that were generated during the creative phase were recorded and each

idea was discussed individually and the advantages and disadvantages of each were

discussed. The Idea Evaluation Summary Table containing all of the ideas, and the rating

applied to each idea, is presented on the following pages. The ideas were assigned a

recommendation for development as follows:

Develop = Develop into VE Alternative Concept

ABD = Being Done or Part of Original Scope

Eliminate = Idea Rejected or Outside Study Scope

Comb w/ No. = Idea Combined with Another Idea


12-25

Table 12-2. Idea Evaluation Summary

No. Idea Description Development

Status

LCA Terrebonne Basin Barrier Shoreline Restoration Study

T-1 Install inverted breakwaters and use fill for replenishing backmarsh Develop

T-2 Calculate renourishment rates required to sustain barrier islands

accounting for absolute sea level rise Develop

T-3 Use a given planning horizon (i.e., 50-year) for renourishment

requirements based on a range of sea level rise Comb w/ T-2

T-4 Obtain a clear definition of the sustainability Study objective Develop

T-5 Include renourishment costs in construction costs Develop

T-6 Establish Federal trust fund for renourishment costs Develop

T-7 Construct new barrier island reach closer to new shoreline Develop

T-8 Relocate Timbalier Islands to the north using existing islands as

sediment source Eliminate

T-9 Incorporate a hard core into barrier islands Comb w/ T-10

T-10 Fix barrier islands in current location; Harden islands to reduce

rate of roll over Develop

T-11 Divert Mississippi River to provide sediment for littoral drift

(Feed the Beast) ABD

T-12 Prioritize which barrier islands should be saved ABD

T-13 Use East Timbalier as a feeder island for other islands Eliminate

T-14 Utilize sand recycling/back-passing for barrier island

renourishment Develop

T-15 Allow revetments Comb w/ T-10

T-16 Use buried revetments Comb w/ T-10

T-17 Use Geotubes for dune core Comb w/ T-10

T-18 Utilize concrete armor units in lieu of rock Comb w/ T-10

T-19 Procure environmental dredging fleet Develop

T-20 Use C-rock for barrier island hardening and relocate as

necessary to allow roll over Eliminate

T-21 Evaluate a retreating strategy for relocating barrier islands

closer to marshes Comb w/ T-7

T-22 Utilize congressional action to allocate Ship Shoal sands Eliminate

T-23 Evaluate actual quantities of available sediment at Ship Shoal

and determine appropriate locations Comb w/ T-42

T-24 Design alternatives for future tidal prism ABD

T-25 Close Wine Island Pass; connect East Island to Wine Island Eliminate

T-26

Construct east end of each island wider than west end to act as

sediment source; ensure islands have sufficient aspect ratio for

coastal geomorphic processes

Develop

T-27 Change the term non-structural in Study documents to soft

structural Develop


12-26

No. Idea Description Development

Status

T-28 Utilize water injection to minimize impacts from fluid

withdrawal-induced subsidence Comb w/ G-6

T-29 Connect the two pieces of East Timbalier Island and close the

pass in between Eliminate

T-30 Prioritize project components based on habitat loss factors Develop

T-31 Investigate additional Mississippi River diversions to provide

sediment for barrier islands ABD

T-32 Implement oil/gas industry outreach program regarding future

sediment management practices Develop

T-33

Conduct offshore sediment analysis to identify alternative

sources of barrier island renourishment sediment; provide

BOEMRE sufficient funds to map sediment sources

Develop

T-34 Consider variable habitat types on barrier islands ABD

T-35 Construct permanent pipeline from Ship Shoal to the east end

of Timbalier Island Develop

T-36 Consider alternate procurement methods for construction Develop

T-37 Construct groins and/or breakwaters with pre-filled sediment Develop

T-38 Run dredges using green technologies in lieu of diesel Comb w/ T-35

T-39 Add Plan Strategy that addresses habitat needs in excess of

budgetary limitations Develop

T-40 Develop Plan Strategies to evaluate differing renourishment

requirements and island hardening alternatives ABD

T-41 Use birth control agents to control nutria Develop

T-42 Use BOEMRE to regulate Ship Shoal quantities to various

projects needing sediment Develop

T-43 Relocate pipelines crossing Ship Shoal to increase sediment

capacities available Eliminate

T-44 Use abandoned pipelines at Ship Shoal for sediment transport Eliminate

T-45 Utilize back-bay material for renourishment of barrier islands Eliminate

General / Plan Formulation

G-1 Use upwelling ram pumps to bring cold water to ocean surface

to reduce hurricane intensities Eliminate

G-2 Use ram pumps to power sediment transport piping Eliminate

G-3 Develop a seasonal freshwater management plan Develop

G-4 Create Federal advisory committee to represent the migratory

bird interest (FACA) Develop

G-5 Perform parametric analysis of Study alternatives accounting

for the three levels of sea level rise Develop

G-6 Identify and incorporate effects of subsidence from fluid

withdrawal into Study analysis Develop


12-27

L12.6 VALUE ENGINEERING STUDY RESULTS

The natural processes of subsidence and erosion have combined with humancaused

effects leading to significant shoreline retreat and land loss along the Terrebonne Basin

barrier island reach. As such, the system is in a continuous need of sediment. The current

Study plans and budget only allow for a single renourishment after about five years,

which means the sustainability of the islands are in doubt. Furthermore, the availability of

suitable sediment from Ship Shoal to restore and maintain the barrier islands may be

limited. Finally, the barrier islands form a complex system of ecological, physical,

chemical, and social processes, which interact in a highly involved and, at times, dynamic

fashion.

Key VE alternatives identified to address these issues are as follows:

Sustain Barrier Island System

o Obtain a clear definition of the Study objectives regarding sustainability; and

o Establish permanent trust fund for renourishment costs.

Provide Sediment for Renourishment

o Use Bureau of Ocean Energy Management, Regulation, and Enforcement to

regulate Ship Shoal quantities to various projects needing sediment;

o Construct a permanent pipeline from Ship Shoal to the east end of East

Timbalier Island;

o Utilize Dynamic Coastal Systems;

o Utilize sand recycling/backpassing for barrier island nourishment;

o Consider coastal geomorphic processes for sediment placement; and

o Construct new barrier island chain closer to new shoreline.

Protect Sediment

o Install inverted breakwaters and use excavated material to construct/replenish

back marsh; and

o Fix barrier islands in their current location, eliminating or minimizing island

roll over, by incorporating a hard core or allow surface armoring.


13-1

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Barras, J.A., Bernier, J.C., and Morton, R.A. 2008. Land area change in coastal

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Scientific Investigations Map 3019, scale 1:250,000, 14 p. pamphlet.

Bruun, P. 1962. Sea Level Rise and a Cause of Erosion. J. Waterway, Port, Coastal and

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C & C Technologies (C & C). 2003a. Whiskey Island West Flank Restoration Project

Using Ship Shoal Sediment Coastal Terrebonne Parish, Louisiana: High Resolution

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East and Gulf Coast Stations, Final Report, DOE/ET/2027477/78/798, prepared by

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Day, J.W., Jr., Hall, C.A.S., Kemp, W.M., and Yanez-Arancibia, A. 1989. Estuarine

Ecology. John Wiley and Sons, New York. 558 pp.

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Pittsburgh, PA, under contract for U.S. Department of Energy; June 14, 1979.

Finkl, C W., Benedet, L., and Campbell, T. 2005. Coastal Planning and Engineering,

Inc. Report for TE-37.


13-2

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Georgiou, I.Y., Fitzgerald, D.M., and Stone, G.W. 2005. The Impact of Physical

Processes along the Louisiana Coast. Journal of Coastal Research, SI(44), 7289. West

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Goodwin & Associates, Inc. 2008. Raccoon Island Shoreline Protection/Marsh Creation

(TE-48) Submerged Cultural Resources Investigations.

Khalil S.M., Finkl, C.W., Andrews, J., and Knotts, C.P. 2007. Restoration-quality Sand

from Ship Shoal, Louisiana: Geotechnical Investigation for Sand on a Drowned Barrier

Island, Coastal Sediments 07.

Syed M. Khalil, Charles W. Finkl, Harry H. Roberts, and Richard C. Raynie. 2010. "New

Approaches to Sediment Management on the Inner Continental Shelf Offshore Coastal

Louisiana", Under publication.

Khalil, S. and Cantu, K. 2008. Vicinity Map, Louisiana Borrow Areas. Coastal

Engineering Division, Louisiana Department of Natural Resources. Annotated map.

Kulp, M, Penland, S., and Ramsey, K. 2001. Ship Shoal: Sand Resource Synthesis

Report. Submitted to Lee Wilson and Associates, Santa Fe, New Mexico.

Kulp, M., Penland, S., Williams, S.J., Jenkins, C., Flocks, J., and Kindinger, J. 2005.

Geological framework, evolution, and sediment resources for restoration of the Louisiana

coastal zone. Journal of Coastal Research, Special Issue (44): 56-71.

Kulp, M.A., Howell, P., Adiau, S., Penland, S.; Kindinger, J., and Williams, S.J. 2002.

Latest Quaternary stratigraphic framework of the Mississippi River delta region. Gulf

Coast Association of Geological Societies Transactions, 52, 573582.

Louisiana Coastal Area (LCA), Louisiana Ecosystem Restoration Study. 2004. Final,

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Whiskey Island West Flank Restoration (TE-47). Coastal Engineering Division, Baton

Rouge, Louisiana, Prepared by DMJM Harris, Inc. December 30, 2005.

Louisiana Department of Natural Resources. 2007. Whiskey Island Back Barrier Marsh

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13-3

Mitsch, W. and Gosselink, J. 2000. Wetlands, John Wiley & Sons 3rd Edition, New York,

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Moffatt & Nichol. 2004. Technical Memorandum: Basis of Design: Proposed Design

Conditions, Criteria, and Screening Process for Ship Shoal: Whiskey Island West Flank

Restoration Project. Prepared for DMJM+Harris.

Nairn, R., Langendyk, S., and J. Michel. 2004. Preliminary Infrastructure Stability

Study, Offshore Louisiana. Prepared by Baird & Associates and Research Planning, Inc.

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Nairn, R., Lu, Q., and Langendyk, S. 2005. A study to address the issue of seafloor

instability and the impact on oil and gas infrastructure in the Gulf of Mexico. U.S. Dept.

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Orleans LA OCS Study MMS 2005-043. 179 pp + appendices.

Natural Resources Conservation Service (NRCS). 2006. Offshore Geophysical and

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Shinkle, K. D. and Dokka, R. K. 2004. Rates of Vertical Displacement at Benchmarks in

the Lower Mississippi River Valley and the Northern Gulf Coast. NOAA Technical

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13-4

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Stone, G.W. 2001. Mining Ship Shoal for large-scale barrier island restoration along the

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Dernieres. Report prepared for the US Environmental Protection Agency, 26p.

Stone, G.W., Pepper, D A., Xu, J., and Zhang, X. 2004. Ship Shoal as a prospective

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13-5

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Louisiana From 1853 to 1989.


TERREBONNE BASIN BARRIER

SHORELINE RESTORATION

APPENDIX L

ENGINEERING INVESTIGATIONS

AND COST ESTIMATES

ANNEX L-1

BORROW AREA DESIGN PLANS





PI NO. EASTING - X NORTHING - Y

1 3468761.35 191479.692 3469056.21 191487.66

3 3469935.92 191186.864 3470338.37 191095.265 3470799.14 191130.066 3472357.76 191505.807 3472263.11 187329.908 3471201.44 187354.449 3470156.75 188176.27

10 3468998.35 186774.4911 3467940.69 186792.1212 3466521.03 188244.9513 3466554.51 188453.1714 3467507.46 189615.9515 3467531.02 190448.93

BORROW AREA LIMITS

CORE NO. EASTING - X NORHTING - Y CORE LENGTH

VC-01 3472404.00 193109.00 19.9'VC-02 3472329.00 190668.00 19.1'VC-03 3472267.00 187427.00 16.7'VC-04 3471171.00 191913.00 19.6'VC-05 3471142.00 190194.00 16.9'VC-06 3471092.00 188311.00 20.0'VC-07 3469989.00 192978.00 16.5'VC-08 3469936.00 190765.00 19.7'VC-09 3469896.00 189083.00 19.8'VC-10 3468755.00 191476.00 20.0'VC-11 3468722.00 190183.00 20.0'VC-12 3468653.00 187169.00 17.5'VC-13 3467569.00 192199.00 20.0'VC-14 3467509.00 189610.00 19.9'VC-15 3467489.00 187809.00 20.1'VC-16 3466392.00 193227.00 19.0'VC-17 3465795.00 192027.00 20.0'VC-18 3466324.00 189400.00 20.0'VC-19 3465140.00 190865.00 20.2'VC-20 3463958.00 192073.00 17.0'VC-41 3468700.00 188386.00 19.8'VC-42 3471733.00 189500.00 19.9'VC-43 3467531.00 190445.00 18.4'VC-44 3468701.00 189571.00 19.8'VC-45 3469926.00 189885.00 19.5'VC-46 3469876.00 188341.00 20.0'VC-47 3472171.00 188295.00 19.8'VC-48 3468767.00 190750.00 17.7'

EXISTING VIBRACORES

REF NO. EASTING - X NORTHING - Y DIMENSIONS DESCRIPTION REF NO. EASTING - X NORTHING - Y DIMENSIONS DESCRIPTION

SS17 3466510.00 184730.60 29' x 16' x NMH OBLONG TARGET SS32 3469752.00 189337.90 74' x 10' x NMH OBLONG TARGETSS18 3468424.00 187189.10 15' x 13' x NMH OBLONG TARGETS SS33 3469666.00 188339.00 12' x 8' x NMH OBLONG TARGETSSS19 3467785.00 187811.40 12' x 4' x NMH OBLONG TARGET SS34 3470025.00 187680.60 18' x 9' x NMH OBLONG TARGETSS20 3467933.00 187979.50 12' x 10' x NMH OBLONG TARGETS SS35 3470218.00 187508.00 11' x 6' x NMH OBLONG TARGETSS21 3467523.00 187769.50 16' x 2' x NMH LINEAR TARGET SS36 3470382.00 187530.00 11' x 6' x NMH OBLONG TARGETSSS22 3467445.00 187687.80 18' x 18' x NMH TRIANGULAR TARGET SS37 3470482.00 187611.00 21' x 5' x NMH OBLONG TARGETSS23 3466924.00 187591.80 14' x 10' x NMH "S" SHAPED TARGET SS38 3471347.00 188015.60 18' x 4' x NMH OBLONG TARGET

SS24 3466637.00 187762.40 18' x 8' x NMH OBLONG TARGET SS39 3471730.00 187977.20 14' x 5' x NMH OBLONG TARGETSS25 3467061.00 188308.10 40' x 17' x NMH OBLONG TARGET SS40 3471856.00 189413.10 18' x 6' x NMH OBLONG TARGETSS26 3467696.00 188602.00 18' x 7' x NMH OBLONG TARGET SS41 3471645.00 189481.40 12' x 8' x NMH OBLONG TARGETSS27 3468703.00 189203.60 23' x 12' x NMH OBLONG TARGET SS42 3470724.00 189841.20 23' x 11' x NMH OBLONG TARGETSS28 3468826.00 189020.80 20' x 8' x NMH OBLONG TARGET SS43 3471214.00 190523.90 23' x 4' x NMH OBLONG TARGETSS29 3468566.00 190292.80 20' x 13' x NMH OBLONG TARGET SS44 3469426.00 190835.30 11' x 8' x NMH OBLONG TARGETSSS30 3468046.00 190453.60 18' x 9' x NMH OBLONG TARGETS SS45 3469010.00 191255.00 17' x 4' x NMH OBLONG TARGETSSS31 3469839.00 189407.00 40' x 22' x NMH OBLONG TARGET

SONAR CONTACTS

NMH = NO MEASURABLE HEIGHT


REF NO. EASTING - X NORTHING - Y GAMMA DURATION DESCRIPTION REF NO. EASTING - X NORTHING - Y GAMMA DURATION DESCRIPTION

154 3468971.00 190611.00 5 45 UNKNOWN 201 3470132.00 187614.00 555 925 WELL SL-15074155 3466942.00 187035.00 85 200 PIPELINE 202 3470206.00 187695.00 205 50 UNKNOWN156 3469211.00 189912.00 13 100 UNKNOWN 203 3470700.00 187301.00 14 1400 WELL SL-15074

157 3467574.00 188634.00 8 75 UNKNOWN 204 3471040.00 187690.00 7 95 UNKNOWN

158 3467062.00 186918.00 105 90 PIPELINE 205 3470321.00 187558.00 497 625 WELL SL-15074159 3467167.00 187045.00 78 110 UNKNOWN 206 3471602.00 187858.00 28 60 OIL & GAS DEBRIS160 3467793.00 187814.00 2069 155 OIL & GAS DEBRIS 207 3471713.00 187969.00 322 110 OIL & GAS DEBRIS161 3466721.00 187290.00 57 110 PIPELINE 208 3470523.00 187576.00 277 600 WELL SL-15074162 3467181.00 186800.00 260 190 PIPELINE 209 3470492.00 187312.00 27 1100 WELL SL-15074163 3467425.00 187140.00 17 70 UNKNOWN 210 3466257.00 187734.00 123 195 PROBABLE PIPELINE

164 3467119.00 187511.00 731 150 OIL & GAS DEBRIS 211 3466783.00 188424.00 10 60 UNKNOWN165 3467655.00 186359.00 132 340 PIPELINE 212 3467905.00 190400.00 5 5 UNKNOWN

166 3470252.00 189620.00 6 140 OIL & GAS DEBRIS 213 3468081.00 190601.00 5 55 UNKNOWN167 3467701.00 187179.00 8 70 UNKNOWN 214 3468308.00 190858.00 28 125 UNKNOWN168 3467808.00 186282.00 97 230 PIPELINE 215 3468335.00 190888.00 14 10 UNKNOWN

169 3469084.00 187880.00 11 150 OIL & GAS DEBRIS 216 3467150.00 187840.00 11 5 UNKNOWN170 3471077.00 190412.00 40 85 UNKNOWN 217 3467138.00 187852.00 12 10 UNKNOWN171 3471171.00 190523.00 3282 235 UNKNOWN 218 3467126.00 187863.00 11 15 UNKNOWN175 3467340.00 186365.00 507 170 PIPELINE 222 3466682.00 188195.00 7 5 UNKNOWN

176 3467452.00 186540.00 113 105 PIPELINE 223 3469845.00 187022.00 178 125 PROBABLE PIPELINE177 3469334.00 188993.00 6 110 UNKNOWN 224 3468611.00 188030.00 14 95 UNKNOWN178 3470333.00 190267.00 21 85 UNKNOWN 225 3470410.00 187899.00 39 2000 WELL SL-15074

179 3468040.00 186318.00 217 290 PIPELINE 226 3467695.00 190034.00 11 150 UNKNOWN180 3468543.00 186930.00 9 145 OIL & GAS DEBRIS 227 3472434.00 187551.00 14 20 UNKNOWN181 3469083.00 187589.00 5 50 UNKNOWN 228 3472418.00 187576.00 8 30 UNKNOWN

182 3471354.00 190500.00 27 100 UNKNOWN 229 3472340.00 187655.00 5 5 UNKNOWN

183 3468871.00 186281.00 387 260 PIPELINE 230 3470419.00 189158.00 30 200 OIL & GAS DEBRIS184 3469995.00 187713.00 91 1600 WELL SL-15074 231 3468286.00 190827.00 5 285 UNKNOWN

185 3471194.00 189215.00 28 200 OIL & GAS DEBRIS 232 3471695.00 189411.00 6 75 UNKNOWN186 3472408.00 190761.00 13 130 UNKNOWN 233 3471616.00 189470.00 5 5 UNKNOWN187 3468265.00 186310.00 510 185 PIPELINE 234 3471469.00 189587.00 5 5 UNKNOWN188 3469665.00 188078.00 6 1700 WELL SL-15074 235 3470146.00 190632.00 5 5 UNKNOWN189 3469719.00 188144.00 49 105 UNKNOWN 236 3468662.00 191798.00 13 5 UNKNOWN190 3472416.00 191585.00 7 55 UNKNOWN 237 3468648.00 191805.00 16 5 UNKNOWN192 3468569.00 186169.00 15 80 UNKNOWN 239 3471781.00 190597.00 20 110 UNKNOWN193 3468662.00 186278.00 338 145 PIPELINE 240 3471872.00 190522.00 6 90 UNKNOWN194 3469884.00 187821.00 30 1500 WELL SL-15074 241 3471768.00 190602.00 8 85 UNKNOWN

195 3472297.00 190878.00 301 150 UNKNOWN 242 3471747.00 190616.00 10 5 UNKNOWN196 3470770.00 190559.00 11 400 UNKNOWN 243 3471192.00 191117.00 5 10 UNKNOWN199 3468403.00 186290.00 697 200 PIPELINE 246 3470867.00 191297.00 5 5 UNKNOWN200 3469732.00 187871.00 13 1800 WELL SL-15074 247 3470606.00 191433.00 6 5 UNKNOWN

UNIDENTIFIED MAGNETIC ANOMALIES




PI NO. EASTING - X NORTHING - Y

1 3510280.67 198366.012 3510148.93 198708.293 3510936.83 198998.674 3510770.80 199398.225 3510524.13 200382.916 3512437.95 200795.767 3512479.98 200474.308 3512297.96 200396.329 3512332.65 200066.07

10 3512356.54 199982.3111 3512414.83 199876.8412 3512808.55 199985.2313 3512870.20 200198.4414 3513064.64 200350.6415 3513008.55 200653.6816 3513283.55 200700.0917 3513221.44 200915.6918 3515499.62 201358.9019 3516095.89 199309.0220 3516081.97 198017.1621 3516177.86 197667.4522 3516651.66 196821.9423 3515681.49 196731.6924 3515495.36 197515.1625 3515281.02 198304.8326 3515303.58 199157.1527 3514581.93 199018.8228 3513761.07 198353.2629 3513306.82 197285.3230 3512876.18 197323.0931 3512837.98 197523.9432 3512692.15 197525.5033 3512174.94 196915.7734 3512180.36 196780.3635 3510777.33 196700.8436 3510546.11 196415.7237 3510450.66 196009.7938 3509966.34 196283.5339 3509499.34 197472.32

BORROW AREA LIMITS

REF NO. EASTING - X NORTHING - Y GAMMA DURATION DESCRIPTION REF NO. EASTING - X NORTHING - Y GAMMA DURATION DESCRIPTION

2 3513749.80 201412.80 20 98 POTENTIALLY SIGNIFICANT 33 3514039.10 196061.80 44 514 POTENTIALLY SIGNIFICANT3 3513800.00 201432.90 33 76 POTENTIALLY SIGNIFICANT 34 3513765.30 197016.60 7 59 DEBRIS4 3516058.40 201165.30 7 113 DEBRIS 35 3513147.60 196932.30 5 58 DEBRIS5 3514466.70 200770.40 8 34 DEBRIS 36 3513103.00 197084.30 5 47 DEBRIS6 3515084.40 200106.40 13 62 DEBRIS 37 3513069.30 197198.70 5 66 DEBRIS7 3513378.90 199675.80 3 199 POTENTIALLY SIGNIFICANT 38 3512945.10 196352.30 6 107 DEBRIS

8 3513614.30 199407.00 19 71 DEBRIS 39 3511093.10 195802.00 7 69 DEBRIS

9 3512731.00 200136.40 11 36 DEBRIS 40 3510613.20 195804.50 5 95 POTENTIALLY SIGNIFICANT

10 3512835.00 199837.90 17 61 DEBRIS 41 3510571.50 195747.90 102 171 POTENTIALLY SIGNIFICANT

11 3513248.80 198372.70 71 197 POTENTIALLY SIGNIFICANT 42 3510504.20 195760.00 62 183 POTENTIALLY SIGNIFICANT12 3514983.00 198831.80 22 81 DEBRIS 43 3510280.20 195501.40 22 81 DEBRIS

13 3516628.60 199102.20 5 47 DEBRIS 44 3510474.00 195562.90 5 84 DEBRIS14 3516520.40 198206.00 16 213 POTENTIALLY SIGNIFICANT 45 3509507.10 195521.10 8 86 DEBRIS

15 3516635.10 198117.70 10 42 POTENTIALLY SIGNIFICANT 46 3510860.40 197062.50 20 61 DEBRIS16 3516509.80 198044.70 6 119 POTENTIALLY SIGNIFICANT 47 3509425.60 197377.50 6 109 POTENTIALLY SIGNIFICANT

17 3516790.40 197813.60 14 120 DEBRIS 48 3509390.20 197364.00 84 178 POTENTIALLY SIGNIFICANT

18 3514896.10 197919.90 54 187 POTENTIALLY SIGNIFICANT 49 3509190.40 197531.90 62 240 POTENTIALLY SIGNIFICANT

19 3514571.80 197842.70 11 86 DEBRIS 50 3509401.00 198633.20 8 59 DEBRIS20 3514795.90 197655.10 42 153 POTENTIALLY SIGNIFICANT 51 3509040.20 198819.40 1237 353 DEBRIS / WELL HEAD21 3514898.60 197696.00 95 141 POTENTIALLY SIGNIFICANT 52 3509110.40 199138.40 94 603 DEBRIS / WELL HEAD22 3515472.40 197159.70 49 101 POTENTIALLY SIGNIFICANT 53 3508961.90 199667.90 7 75 DEBRIS

23 3514987.20 196998.70 8 82 DEBRIS 54 3511284.50 199195.70 25 77 DEBRIS24 3515525.90 196756.60 8 53 DEBRIS 55 3511516.10 202045.30 9 52 DEBRIS

25 3515706.00 195600.80 10 86 DEBRIS 56 3511035.20 201396.60 12 83 DEBRIS

26 3514636.40 195771.70 6 45 DEBRIS 57 3510962.10 201619.00 5 48 DEBRIS27 3514415.00 196325.50 6 59 DEBRIS 58 3508799.30 201468.70 19 94 DEBRIS

28 3514381.00 196150.80 43 175 POTENTIALLY SIGNIFICANT 59 3508218.10 201020.20 9 52 DEBRIS29 3514360.90 195946.90 76 221 POTENTIALLY SIGNIFICANT 60 3506922.50 201493.90 101 123 OUT OF AREA

30 3514265.50 195947.70 129 390 POTENTIALLY SIGNIFICANT 61 3506829.40 201358.20 1650 199 OUT OF AREA

31 3514181.60 195790.30 53 318 POTENTIALLY SIGNIFICANT

UNIDENTIFIED MAGNETIC ANOMALIES

CORE NO. EASTING - X NORHTING - Y CORE LENGTH CORE NO. EASTING - X NORHTING - Y CORE LENGTH

NCVC-05-01 3514635.00 200469.00 15' NCVC-05-16 3515758.00 199037.00 17.1'NCVC-05-02 3512890.00 198966.00 19.4' NCVC-05-17 3512711.00 196612.00 14.1'NCVC-05-03 3511602.00 198748.00 19.8' NCVC-05-18 3511006.00 197401.00 17.1'NCVC-05-04 3511899.00 196950.00 15.1' NCVC-05-19 3510254.00 196717.00 14.8'NCVC-05-05 3510192.00 197678.00 15.5' NCVC-05-20 3511247.00 196457.00 16.3'NCVC-05-06 3511720.00 197826.00 17.3' NCVC-05-21 3512639.00 197502.00 17.5'

NCVC-05-07A 3512239.00 199504.00 19.2' NCVC-05-22 3512415.00 198355.00 14.9'

NCVC-05-08 3513740.00 199023.00 16.5' NCVC-05-23A 3510673.00 198321.00 15.0'NCVC-05-09 3515390.00 199829.00 17.5' NCVC-05-24 3511368.00 199606.00 15.0'NCVC-05-10 3513823.00 200471.00 16.9' NCVC-05-25 3512951.00 199875.00 15.0'

NCVC-05-11B 3514412.00 201332.00 18.1' NCVC-05-26 3512477.00 201197.00 15.0'

NCVC-05-12 3515390.00 201095.00 18.3' NCVC-05-27 3510942.00 201022.00 15.2'NCVC-05-13 3514534.00 199672.00 18.4' NCVC-05-28 3510275.00 199713.00 16.5'NCVC-05-14 3515695.00 198025.00 17.0' NCVC-05-29 3508981.00 200686.00 15.5'NCVC-05-15 3515887.00 197165.00 9.0'

EXISTING VIBRACORES




PI NO. EASTING - X NORTHING - Y

1 3408605.36 180040.862 3409117.87 180352.853 3410415.01 178222.024 3410519.34 178095.955 3410928.50 177590.826 3411717.33 176621.147 3412229.15 175727.188 3412410.65 175266.259 3412790.77 173257.98

10 3412152.09 173038.6911 3411787.65 173768.2112 3411860.31 175008.7313 3411664.84 175504.8414 3411260.59 176241.5915 3410461.72 177202.9216 3410046.27 177702.8417 3409980.29 177782.25

BORROW AREA LIMITS

REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA

M01 3409390.00 178369.28 39.4 M28 3412300.96 171481.84 1072.0 M55 3412635.59 175082.86 10.0M02 3409452.24 178249.77 41.8 M29 3412227.65 171977.17 16.1 M56 3412757.50 172819.79 296.3M03 3410479.45 176907.70 17.4 M30 3412406.54 171516.31 169.8 M57 3409576.43 171925.49 15.6M04 3412000.72 175156.09 17.9 M31 3412344.55 171840.50 12.7 M58 3411611.41 172560.56 19.6M05 3409021.25 179113.92 25.7 M32 3411888.39 173521.80 11.6 M59 3413990.69 173416.91 13.4M06 3408772.49 179562.99 12.3 M33 3411920.05 174115.99 24.2 M60 3413877.97 176085.42 656.4M07 3409748.50 178173.52 14.8 M34 3411811.32 174627.18 20.9 M61 3413698.67 176008.32 1084.5M08 3412300.95 175076.78 14.4 M35 3412492.47 171564.62 154.4 M62 3410416.26 174688.55 10.0M09 3411011.81 176874.04 44.6 M36 3412470.04 171742.31 32.4 M63 3410047.18 175759.18 13.8M10 3410126.31 178066.60 535.6 M37 3411824.54 175219.68 490.5 M64 3410747.24 175676.32 122.1M11 3410120.05 178108.94 22.6 M38 3412593.39 171623.82 1465.6 M65 3408381.79 179035.15 996.4M12 3408426.55 181118.79 14.1 M39 3411730.15 175999.96 10.7 M66 3407160.74 181048.22 131.9M13 3412049.34 176213.28 30.9 M40 3412003.03 175173.78 21.5 M67 3413759.09 176040.83 109.5M14 3412651.37 175567.92 10.9 M41 3412686.91 171658.95 78.3 M68 3413314.79 176590.95 17.1M15 3409652.69 179823.22 98.9 M42 3412725.62 171491.86 13.3 M69 3411008.14 171164.12 594.7M16 3407587.12 178510.62 39.9 M43 3412767.86 171713.86 103.5 M70 3411540.24 171129.56 102.6M17 3407632.67 178509.08 140.8 M44 3412887.38 171743.20 1073.8 M71 3413731.06 172139.77 75.5M18 3408418.58 178981.43 31.7 M45 3412444.07 174068.86 14.8 M72 3414248.52 172226.97 59.2M19 3411136.84 177730.74 30.0 M46 3412737.13 172935.10 3758.0 M73 3410353.16 181866.33 214.6M20 3411297.87 175159.34 11.5 M47 3412948.10 171760.51 449.8 M74 3414330.55 176321.95 23.8M21 3411864.77 172334.22 15.8 M48 3412255.86 175546.01 53.8 M75 3410512.42 170635.93 209.3M22 3412026.12 171368.55 376.5 M49 3413081.78 171820.12 2524.1 M76 3414801.43 172566.45 456.3M23 3412122.00 171403.24 690.9 M50 3412531.89 174558.10 21.3 M77 3406582.82 180997.02 20.2M24 3411961.49 172220.83 17.4 M51 3412304.48 175828.44 18.4 M78 3412002.28 176172.87 64.1M25 3412200.71 171443.91 520.1 M52 3413144.43 171873.93 1395.6 M79 3413885.02 172188.41 642.4M26 3412039.24 172386.21 14.5 M53 3413255.13 171901.42 128.7 M80 3413797.26 172154.92 101.8M27 3412124.06 171924.14 15.6 M54 3413480.16 170697.53 18.8 M81 3413709.04 172118.90 323.2

UNIDENTIFIED MAGNETIC ANOMALIES - GOODWIN 2008

CORE NO. EASTING - X NORHTING - Y CORE LENGTH

VC-1 3412092.17 174579.20 19.9VC-2 3415258.36 169712.63 18.5VC-3 3416434.18 168834.96 17.2VC-4 3418610.29 163431.83 20.3VC-5 3418607.94 162425.28 20.3

C-1 3412004.19 175080.01 17.5C-2 3412478.93 174422.77 19.9C-3 3411900.01 174073.91 18.2C-4 3412654.91 173952.40 19.7C-5 3412027.87 173483.91 18.3C-6 3412672.29 173468.12 18.0C-7 3412380.11 173106.35 18.0C-8 3412579.51 172700.84 20.1

EXISTING VIBRACORES

REF NO. EASTING - X NORTHING - Y GAMMA

1 3411020.05 178079.71 102 3412077.62 176245.95 603 3411931.81 171408.60 455 3413142.53 171878.10 2506 3413019.65 171769.26 607 3413790.18 172375.80 60

UNIDENTIFIED MAGNETIC ANOMALIES - SJB 2006





PI NO. EASTING - X NORTHING - Y PI NO. EASTING - X NORTHING - Y

1 3492105.07 155787.41 13 3509703.72 155866.702 3497544.99 155811.92 14 3519357.50 155910.193 3502541.80 148709.91 15 3519357.50 150942.024 3491101.12 153489.65 16 3490969.14 152461.035 3491168.34 154013.62 17 3502404.45 147683.536 3500860.53 155826.86 18 3501065.31 145540.827 3507512.53 155856.82 19 3491413.08 144866.338 3504166.08 150502.27 20 3488443.86 146141.919 3508386.57 155416.02 21 3490775.60 150952.59

10 3517833.97 150596.61 22 3503433.27 147442.8711 3506312.76 147044.39 23 3504597.83 145787.6712 3504753.72 149555.69 24 3502298.39 145626.99

BORROW AREA LIMITS

CORE NO. EASTING - X NORTHING - Y CORE LENGTH CORE NO. EASTING - X NORTHING - Y CORE LENGTH

BSS00-SS-02 3510374.58 151986.47 6.8' CHVC-05-09 3499334.00 150525.00 20.3'BSS00-SS-03 3498181.47 150536.38 6.3' CHVC-05-10 3499462.00 152334.00 18.3'BSS00-SS-05 3511003.53 149511.61 3.7' CHVC-05-11 3506249.00 150900.00 17.4'

SS-86-25 3505866.77 155263.95 43.5' CHVC-05-12 3507325.00 148255.00 19.8'

CHVC-05-01 3494722.00 148350.00 20.3' CHVC-05-13 3505807.00 149274.00 18.8'CHVC-05-02 3495823.00 149727.00 19.7' CHVC-05-14 3507878.00 151887.00 20.1'CHVC-05-03 3497155.00 148742.00 20.2' CHVC-05-15 3511655.00 150121.00 19.4'CHVC-05-04 3493620.00 150207.00 17.4' CHVC-05-16 3511981.00 151718.00 19.9'CHVC-05-05 3493160.00 148728.00 20.2' CHVC-05-17 3513638.00 151562.00 20.0'CHVC-05-06 3496427.00 152167.00 17.2' CHVC-05-18 3509796.00 149936.00 19.9'CHVC-05-07 3498531.00 152180.00 19.8' CHVC-05-19 3507954.00 150416.00 13.8'CHVC-05-08 3498380.00 150829.00 15.3' CHVC-05-20 3498081.00 144304.00 20.2'

EXISTING VIBRACORES

REF NO. EASTING - X NORTHING - Y DIMENSION DESCRIPTION

1 3516468.73 154820.03 13' x 6' x NMH Debris2 3517057.74 154161.01 15' x 11' x NMH Debris3 3517057.74 154161.01 15' x 9' x NMH Debris4 3510351.78 152178.04 4' x 2' x NMH Debris5 3505345.73 155665.17 14' x 3' x NMH Debris6 3503919.72 155944.20 15' x 2' x NMH Debris7 3502310.75 154552.19 7' x 2' x NMH Debris8 3503412.85 148342.04 17' x 15' Debris9 3496941.76 153955.24 Debris Zone Debris Zone

10 3488217.90 145889.17 16' x 17' x NMH Debris11 3488144.90 145740.17 9' x 13' x NMH Debris12 3487217.89 146422.19 Debris Zone Debris Zone

SONAR CONTACTS

NMH = NO MEASURABLE HEIGHT


REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA REF NO. EASTING - X NORTHING - Y GAMMA

1 3500924.83 155805.78 33 61 3515948.74 154389.02 32 121 3498914.78 152840.19 3 181 3493319.82 150360.20 5 241 3512431.84 148791.95 4 301 3493512.89 146109.11 22 3503461.06 155795.05 4 62 3517499.74 154394.01 3 122 3489356.79 152647.30 3 182 3493476.82 150363.20 1 242 3509752.84 148620.98 19 302 3496945.89 146113.07 9963 3503971.79 155811.63 4 63 3495538.76 154153.26 5 123 3490756.79 152656.28 9 183 3501454.82 150396.11 3 243 3508355.84 148611.99 13 303 3502329.89 145970.01 264 3506802.72 155814.16 30 64 3495890.76 154154.25 3 124 3495148.79 152662.23 5 184 3516188.81 150446.94 6 244 3493788.85 148561.16 4 304 3500333.89 145963.03 95 3509361.72 155830.13 4 65 3496871.76 154159.24 16 125 3496349.78 152671.22 3 185 3501212.82 150229.11 29 245 3498578.85 148416.10 16 305 3496936.89 145947.07 66 3511582.72 155849.10 12 66 3512949.74 154216.06 3 126 3505415.78 152711.11 8 186 3501251.82 150229.11 13 246 3499503.85 148415.09 4 306 3490474.89 145927.14 47 3514187.71 155848.07 8 67 3515881.74 154223.02 11 127 3519176.77 152596.95 4 187 3494864.82 150208.18 5 247 3500859.85 148422.08 9 307 3492879.90 145769.11 178 3497611.74 155634.26 12 68 3517402.74 154221.00 17 128 3516754.77 152573.98 19 188 3491285.83 150192.22 363 248 3507158.85 148449.00 4 308 3498299.89 145792.05 2

9 3501380.73 155645.22 5 69 3491732.77 153974.30 4 129 3509545.78 152558.06 16 189 3491269.83 150029.22 1932 249 3507286.85 148449.00 7 309 3502399.89 145799.00 6

10 3503415.73 155645.20 3 70 3496919.76 153986.24 1674 130 3491499.79 152325.27 3 190 3492329.83 150035.21 12 250 3508062.85 148444.99 17 310 3502227.90 145639.00 1211 3493065.74 155446.31 3 71 3496575.76 153981.24 19 131 3495144.79 152337.22 5 191 3494437.83 150045.18 22 251 3493895.86 148062.15 4 311 3492702.90 145603.11 512 3493227.74 155450.31 10 72 3512569.75 154041.06 6 132 3504049.78 152376.12 2 192 3494839.83 150046.18 5 252 3503865.85 148106.04 14 312 3492642.90 145438.11 3

13 3495163.74 155449.29 4 73 3513380.75 154039.05 9 133 3504306.78 152377.12 5 193 3500811.82 150057.11 22 253 3508818.85 148118.98 3 313 3493978.90 145439.09 2

14 3503739.73 155490.19 4 74 3515807.74 154053.02 11 134 3510722.78 152395.04 3 194 3505785.82 150077.05 3 254 3510724.85 148130.96 5 314 3502773.90 145481.99 315 3504185.73 155490.18 4 75 3517093.74 154056.00 54 135 3517496.77 152258.96 8 195 3506614.82 150084.04 3 255 3503016.85 148266.05 45 315 3503674.90 145315.98 27

16 3508668.73 155498.13 29 76 3517328.74 154055.00 18 136 3511242.76 153226.06 3 196 3509882.82 150099.01 3 256 3499359.85 148254.09 10 316 3502384.90 145305.99 1217 3512121.72 155511.09 60 77 3517628.74 154053.00 6 137 3510257.78 152221.05 16 197 3515381.81 150117.94 5 257 3494498.86 148234.15 5 317 3498703.90 145297.04 10

18 3493249.75 155281.31 8 78 3491221.77 153798.30 9 138 3506998.78 152213.08 5 198 3515337.82 149949.94 49 258 3492952.86 148225.16 8 318 3494893.90 145289.08 31

19 3495111.74 155291.29 26 79 3496976.77 153815.23 2467 139 3503986.79 152203.12 2 199 3512248.82 149930.98 2 259 3490627.86 148226.19 4 319 3490102.91 145267.13 420 3496030.74 155299.28 25 80 3497396.76 153824.23 30 140 3494006.79 152170.23 5 200 3510132.82 149936.00 17 260 3489297.86 148206.20 12 320 3503228.90 145136.98 4021 3502955.74 155316.19 6 81 3497505.76 153826.23 6 141 3489820.80 151994.28 6 201 3510058.82 149936.00 10 261 3506887.86 147955.00 3 321 3502306.91 144988.99 3222 3504012.73 155319.18 6 82 3505907.76 153858.13 6 142 3494131.80 152009.23 9 202 3499630.83 149889.12 8 262 3503869.86 147939.03 16 322 3498068.91 144808.03 323 3504298.73 155321.18 6 83 3512089.75 153881.06 26 143 3502998.79 152048.13 7 203 3491275.83 149862.22 72 263 3500786.86 147933.07 6 323 3494908.91 144631.07 5

24 3505464.73 155331.17 3 84 3513788.75 153874.04 3 144 3504239.79 152045.11 9 204 3491285.84 149710.21 15 264 3496748.86 147920.11 3 324 3492637.92 144610.09 825 3506815.73 155332.15 3 85 3515737.75 153893.02 8 145 3506868.79 152060.08 4 205 3493246.83 149706.19 22 265 3496109.86 147910.12 3 325 3492994.92 144458.08 2

26 3508635.73 155338.13 38 86 3517226.75 153893.00 7 146 3513547.78 152083.01 3 206 3504769.83 149748.06 5 266 3495968.86 147908.12 2 326 3492928.92 144140.08 8

27 3513103.72 155350.08 43 87 3496615.77 153663.23 20 147 3514700.78 152072.99 16 207 3510148.82 149777.00 9 267 3491287.87 147728.17 5 327 3493626.92 144139.07 12

28 3494043.75 155118.30 7 88 3497075.77 153663.23 8 148 3511097.79 151909.03 20 208 3514198.82 149612.95 53 268 3499725.86 147758.08 4 328 3499475.92 144151.00 229 3496009.74 155136.27 9 89 3497194.77 153663.23 11 149 3490131.80 151829.27 12 209 3510120.83 149605.99 9 269 3500180.86 147760.07 2 329 3498679.96 141524.96 3

30 3502046.74 155164.20 6 90 3509852.76 153703.08 4 150 3492672.80 151682.24 17 210 3509891.83 149602.00 18 270 3501029.86 147597.06 2 330 3518340.81 150384.92 231 3504056.74 155155.18 79 91 3515634.75 153730.01 5 151 3509149.79 151736.05 58 211 3499645.83 149569.11 6 271 3491789.87 147560.16 38 331 3518333.75 153488.98 2

32 3504347.74 155155.18 7 92 3519448.75 153735.97 119 152 3506567.79 151562.08 6 212 3494582.84 149546.17 10 272 3491258.87 147565.17 3 332 3515393.82 149981.94 10

33 3506914.73 155176.15 17 93 3496811.77 153491.23 5 153 3500424.80 151540.15 2 213 3492722.84 149545.19 2 273 3490581.87 147570.18 4 333 3512422.76 153587.05 19

34 3508569.73 155179.13 12 94 3496894.77 153491.23 48 154 3499307.80 151534.16 2 214 3491468.84 149541.21 9 274 3489973.87 147571.18 5 334 3512420.75 154192.06 2

35 3512090.73 155192.09 3 95 3504261.76 153524.14 5 155 3497973.80 151530.17 2 215 3490353.84 149536.22 3 275 3489388.87 147380.19 17 335 3509474.78 152501.06 636 3510716.73 155033.10 13 96 3512553.76 153554.05 28 156 3497528.80 151542.18 7 216 3492466.84 149373.19 15 276 3490569.87 147387.17 27 336 3506529.82 150040.04 3

37 3513971.73 155036.06 18 97 3516991.75 153560.00 11 157 3488786.81 151357.28 5 217 3496603.84 149400.15 6 277 3490809.87 147390.17 6 337 3503584.72 156177.21 3

38 3516069.73 155033.04 5 98 3493860.78 153311.26 5 158 3493746.81 151348.22 15 218 3498660.84 149396.12 8 278 3491818.87 147406.16 10 338 3503547.73 155663.20 239 3494400.75 154799.28 3 99 3494458.78 153314.25 7 159 3511664.79 151414.01 6 219 3500880.83 149430.10 3 279 3497779.87 147439.09 2 339 3503565.80 151576.11 840 3508450.74 154844.12 3 100 3494945.77 153321.25 5 160 3509830.80 151247.03 11 220 3509394.83 149449.00 10 280 3501530.87 147453.05 2 340 3503583.87 146897.01 4

41 3514022.73 154879.06 24 101 3495692.77 153328.24 12 161 3509200.80 151244.04 9 221 3510113.83 149455.99 3 281 3501392.87 147272.05 5 341 3503569.90 145363.98 2842 3516043.73 154880.03 8 102 3496401.77 153333.23 5 162 3492442.81 151179.23 14 222 3512923.83 149460.96 9 282 3496269.87 147254.10 4 342 3500619.82 149981.11 33

43 3490178.76 154608.33 8 103 3510476.76 153370.07 5 163 3490641.81 151184.25 2 223 3514200.83 149462.94 2 283 3491731.87 147244.16 10 343 3494756.83 149999.18 5

44 3492508.76 154617.30 4 104 3513994.76 153389.03 6 164 3501912.81 151052.12 4 224 3513062.83 149289.95 22 284 3488585.88 147068.19 9 344 3494760.83 150161.18 6

45 3502396.75 154667.19 3 105 3516858.76 153399.99 113 165 3502359.81 151054.11 11 225 3509989.83 149277.99 22 285 3503671.87 146950.01 2 345 3494727.74 155336.29 24

46 3507692.74 154681.13 82 106 3517690.75 153400.98 16 166 3510740.80 151101.02 20 226 3493888.84 149213.17 2 286 3501356.87 146944.04 17 346 3491774.83 150265.22 1047 3508708.74 154690.11 17 107 3517692.76 153241.98 3 167 3500427.81 150882.13 2 227 3491493.84 149207.20 148 287 3493975.88 146919.12 2 347 3491771.87 147510.16 76

48 3513208.74 154704.06 52 108 3516858.76 153236.99 21 168 3491509.82 150855.23 8 228 3489850.84 149210.22 58 288 3493241.88 146912.13 5 348 3491767.87 147294.16 3049 3492569.76 154460.30 4 109 3510389.76 153209.06 2 169 3491450.82 150855.24 6 229 3499201.84 149071.11 29 289 3490085.88 146913.17 4 349 3488789.90 145341.15 950 3496078.76 154481.26 3 110 3504494.77 153191.13 19 170 3491270.82 150681.23 19 230 3506678.84 149115.02 3 290 3486989.88 146903.20 11 350 3488799.89 146591.18 3

51 3497865.75 154472.24 7 111 3496427.78 153164.23 6 171 3491544.82 150682.23 5 231 3512078.83 149118.96 4 291 3494245.88 146602.11 5 351 3500224.80 151801.15 2

52 3506520.75 154508.14 5 112 3495151.78 153159.24 2 172 3498461.81 150712.15 18 232 3513158.83 149127.95 4 292 3490735.88 146570.15 2 352 3505629.74 155126.16 353 3514135.74 154549.05 4 113 3494830.78 152994.24 1 173 3502245.81 150727.11 18 233 3512050.84 148956.96 9 293 3490586.88 146570.16 2 353 3509190.77 152851.07 6

54 3516001.74 154541.03 21 114 3495136.78 152990.24 12 174 3510597.81 150755.01 36 234 3510946.84 148943.97 7 294 3492116.89 146424.13 5 354 3509392.77 152704.07 3

55 3517558.73 154547.01 5 115 3507616.77 153033.09 511 175 3517446.80 150770.93 3 235 3499577.84 148908.10 13 295 3493996.89 146433.11 7 355 3510597.79 151841.03 756 3518215.73 154556.00 6 116 3516951.76 152911.98 4 176 3517442.80 150626.93 3 236 3498487.84 148911.11 7 296 3503729.88 146278.00 2 356 3510931.82 149789.99 4

57 3491215.76 154295.31 10 117 3509743.77 152886.07 3 177 3510606.81 150596.01 5 237 3497942.84 148913.12 3 297 3500863.89 146289.03 28

58 3491970.76 154276.30 377 118 3509193.77 152881.07 2 178 3505718.81 150575.07 6 238 3490023.85 148878.21 46 298 3496944.89 146261.08 9

59 3492539.76 154293.30 654 119 3508474.77 152882.08 2 179 3491250.82 150518.23 33 239 3501894.84 148757.07 2 299 3489494.89 146247.16 36

60 3506484.75 154356.13 9 120 3507643.77 152877.09 12 180 3491268.82 150362.23 147 240 3506804.84 148771.02 7 300 3494185.89 146105.10 6

UNIDENTIFIED MAGNETIC ANOMALIES




MAP ID CORE NO. EASTING - X NORTHING - Y CORE LENGTH MAP ID CORE NO. EASTING - X NORTHING - Y CORE LENGTH

47-1 04-SS88-01(P) 3410321.54 154047.21 19.8' 47-19 04-SS88-17(S) 3414397.00 151619.81 19.7'47-2 04-SS88-27(S) 3411448.82 154065.35 18.2' 47-20 04-SS88-18(S) 3415403.98 151651.88 22.3'47-3 04-SS88-28(S) 3412437.19 154067.44 14.3' 47-21 04-SS88-19(S) 3416460.46 151597.59 19.1'47-4 04-SS88-29(S) 3413411.74 154067.45 17.0' 47-22 04-SS88-12(S) 3410285.60 150282.68 17.9'47-5 04-SS88-30(S) 3414363.63 154070.13 18.3' 47-23 04-SS88-11(S) 3411448.22 150364.41 15.4'47-6 04-SS88-31(S) 3415358.37 154066.82 18.9' 47-24 04-SS88-10(S) 3412433.78 150283.75 14.0'47-7 04-SS88-02(P) 3416476.70 154063.79 19.4' 47-25 04-SS88-09(S) 3413401.81 150318.29 20.9'47-8 04-SS88-26(S) 3410305.21 152818.60 20.0' 47-26 04-SS88-08(S) 3414373.82 150329.10 18.5'47-9 04-SS88-25(S) 3411430.41 152798.42 21.0' 47-27 04-SS88-07(S) 3415365.53 150362.09 19.1'

47-10 04-SS88-24(S) 3412449.58 152771.41 19.6' 47-28 04-SS88-06(S) 3416431.98 150315.90 19.8'47-11 04-SS88-23(S) 3413442.34 152733.24 19.5' 47-29 04-SS88-04(P) 3410322.40 148952.97 15.5'47-12 04-SS88-22(S) 3414386.16 152777.71 19.3' 47-30 04-SS88-01(S) 3411445.72 148960.55 19.8'47-13 04-SS88-21(S) 3415354.70 152757.81 19.7' 47-31 04-SS88-02(S) 3412417.32 148958.70 16.6'47-14 04-SS88-20(S) 3416432.52 152760.53 18.4' 47-32 04-SS88-03(S) 3413437.44 148977.13 19.1'47-15 04-SS88-13(S) 3410332.26 151670.33 21.1' 47-33 04-SS88-04(S) 3414370.61 149016.16 15.8'47-16 04-SS88-14(S) 3411461.87 151664.78 19.8' 47-34 04-SS88-05(S) 3415391.07 148998.45 17.8'47-17 04-SS88-15(S) 3412416.96 151610.98 16.8' 47-35 04-SS88-03(P) 3416424.28 148999.31 22.7'47-18 04-SS88-16(S) 3413373.61 151626.21 19.7'

TE-47 VIBRACORES

PI NO. EASTING - X NORHTING - Y

1 3403522.40 154737.112 3412038.27 154736.953 3427212.51 152104.304 3427927.32 148798.565 3425373.67 144763.596 3409191.78 142936.56

BORROW AREA LIMITS

CORE NO. EASTING - X NORHTING - Y CORE LENGTH

SS-86-11 3422326.21 148037.75 34.78'

SS-92-4 3416522.63 152073.46 17.19'SS-92-5 3410475.18 153061.74 14.27'SS-92-6 3406651.85 153553.48 13.94'SS-92-7 3410312.61 148818.33 15.35'SS-92-8 3416268.43 148739.20 13.94'

EXISTING VIBRACORES

REF NO. EASTING - X NORTHING - Y DIMENSIONS DESCRIPTION

1 3416482.62 144622.67 6' diameter Debris2 3423395.44 154829.94 25' x 5' x NMH Debris3 3420587.59 140554.66 5' diameter x 1' Debris4 3418191.52 154504.86 57' x 25' x NMH Debris5 3410197.73 140839.52 1' x 1' x 1' Debris6 3403698.74 154129.63 16' x 4' x NMH Debris7 3412435.69 141535.56 3' diameter x 0.5' Debris8 3404340.73 154165.64 16' x 4' x NMH Debris9 3424310.53 141857.73 8' x 6' x NMH Debris

10 3414349.58 154338.79 23' x 8' x NMH Debris11 3420009.59 142152.68 3' diameter x 0.5' Debris12 3427604.38 154009.99 23' x 6' x NMH Debris13 3423891.53 143046.75 8' x 2' x 0.5' Debris14 3421874.47 153850.90 33' x 33' x NMH Disturbed Area15 3424347.52 143362.76 17' x 1' x NMH Debris16 3407181.69 153717.68 23' Linear Debris17 3426559.41 153193.96 6' x 0.5' x 1' Debris18 3405351.72 153153.64 16' Linear Debris19 3427859.39 152688.97 8' x 7' x NMH Debris20 3410683.65 152525.71 19' Linear Debris21 3424542.45 151755.90 7' x 1.5' x NMH Debris22 3409585.67 151730.68 6' x 1' x 0.8' Debris23 3411485.64 151656.71 4' x 4' x NMH Debris24 3417808.55 151394.80 5' x 1.5' x NMH Debris25 3413351.63 149041.70 8' x 6' x NMH Debris26 3413463.63 148718.69 6' x 6' x NMH Debris27 3426004.45 148431.87 3' x 3' x 1' Debris28 3420740.53 147932.78 8 x 8' x NMH Debris29 3422444.52 147204.80 8' x 8' x 37' Buoy / Chain30 3415119.62 147158.69 6' x 6' x NMH Debris

SONAR CONTACTS

NMH = NO MEASURABLE HEIGHT

REF NO. EASTING - X NORHTING - Y GAMMA REF NO. EASTING - X NORHTING - Y GAMMA REF NO. EASTING - X NORHTING - Y GAMMA REF NO. EASTING - X NORHTING - Y GAMMA

1 3415582.47 154900.88 4 43 3417790.72 151455.66 8 85 3418467.80 147669.75 9 127 3414476.93 143914.30 82 3411495.39 154730.34 15 44 3427356.83 151295.96 5 86 3405885.81 147689.36 10 128 3418785.15 143913.60 83 3404305.42 154581.92 27 45 3417134.92 150966.51 45 87 3407583.59 147521.91 7 129 3424493.40 143752.87 64 3404659.01 154580.26 21 46 3414689.81 150963.15 8 88 3413083.44 147518.02 80 130 3419462.50 143589.64 145 3408008.50 154572.32 13 47 3407184.87 150791.54 342 89 3421092.16 147519.87 8 131 3409860.74 143248.57 46 3411086.30 154589.14 14 48 3411056.71 150793.92 5 90 3425374.56 147366.09 5 132 3425126.55 143090.40 2257 3414921.07 154565.93 43 49 3412529.67 150801.87 7 91 3424859.54 147359.39 9 133 3420193.68 143094.31 188 3423682.56 154577.27 13 50 3421712.38 150790.80 4 92 3407507.41 147354.11 69 134 3419885.84 143091.98 169 3416088.07 154254.02 7 51 3428312.74 150631.59 6 93 3406918.53 147357.89 69 135 3419132.23 142920.05 8

10 3423099.72 154253.27 5 52 3423409.24 150632.63 6 94 3407900.16 147201.45 7 136 3417076.52 142930.89 1111 3416091.87 154088.15 11 53 3405288.36 150465.42 10 95 3409975.40 147198.89 80 137 3416882.80 142745.91 1012 3408402.28 154083.02 8 54 3414349.37 150459.36 5 96 3421010.44 147195.86 10 138 3415914.01 142759.00 1613 3415522.00 153921.32 14 55 3418813.33 150473.46 4 97 3422456.39 147156.99 15 139 3409934.94 142754.58 914 3417995.09 153764.60 5 56 3422452.01 150471.20 8 98 3424939.25 147200.38 12 140 3416932.51 142276.76 2115 3415538.34 153756.87 8 57 3421752.49 150313.01 6 99 3425737.10 147192.91 43 141 3423482.22 142108.01 1316 3414407.85 153578.76 5 58 3412679.72 150316.01 21 100 3426073.43 147184.38 16 142 3423561.08 141779.75 3117 3415985.69 153602.17 7 59 3427018.80 149986.39 14 101 3426752.93 147193.27 4 143 3422049.88 141450.42 618 3419304.32 153578.79 9 60 3427322.99 149991.84 8 102 3423891.66 147023.42 19 144 3420426.71 141453.31 619 3418083.02 153420.74 8 61 3423729.18 149989.75 55 103 3413962.41 147022.83 4 145 3417088.60 141439.62 4720 3415986.88 153415.78 7 62 3407209.14 149982.86 5 104 3421266.30 146868.35 8 146 3411906.64 141447.80 2321 3415903.08 153412.38 4 63 3405355.96 149826.25 3 105 3423144.86 146702.53 8 147 3411365.68 140959.65 722 3409035.66 153433.15 59 64 3423723.07 149642.09 20 106 3415984.84 146698.77 6 148 3424339.74 140798.27 2223 3419801.84 153251.96 35 65 3425509.43 149650.30 14 107 3415228.70 146366.53 10 149 3418511.30 140795.62 89124 3418648.71 152943.33 8 66 3416293.60 149478.13 14 108 3417139.16 146369.86 7 150 3413143.69 140470.31 725 3423671.97 152927.14 11 67 3418413.03 149305.59 7 109 3422208.06 146366.88 39 151 3415463.36 140310.43 1926 3418475.02 152764.88 12 68 3413390.65 149161.57 34 110 3412633.70 146206.02 9 152 3417136.86 140307.99 10027 3415810.00 152765.78 472 69 3412738.08 149156.48 8 111 3413287.97 146206.47 5 153 3411342.86 139962.57 1828 3412818.07 152769.77 27 70 3426277.15 149160.68 10 112 3425452.88 146037.49 7 154 3411426.74 139967.92 529 3414168.01 152768.56 12 71 3415486.77 149001.32 64 113 3419558.31 145869.82 6 155 3415964.59 139970.68 2030 3425115.06 152599.54 17 72 3423058.25 148839.22 8 114 3424247.20 145717.99 6 156 3417484.70 139493.74 1831 3415729.73 152436.95 12 73 3427416.13 148667.56 19 115 3422527.90 145717.65 6 157 3413170.23 139158.22 2932 3427142.62 152266.82 11 74 3423031.55 148656.38 728 116 3421012.41 145720.64 12 158 3411203.00 138819.80 1233 3418696.65 152281.59 13 75 3422668.76 148493.92 10 117 3410807.79 145552.22 12 159 3425480.42 145977.35 60634 3404671.86 152275.52 30 76 3428119.87 148331.25 16 118 3420715.24 145565.61 8 160 3419552.27 145840.16 535 3417752.60 151954.59 6 77 3417435.92 148342.65 17 119 3411917.87 145224.11 11 161 3419587.80 139702.23 836 3416818.86 151793.10 6 78 3409955.82 148334.47 10 120 3410390.02 144901.49 5 162 3413662.41 140134.68 4737 3417360.09 151793.68 5 79 3427215.38 148019.21 4 121 3415416.41 144896.65 5 163 3413663.97 144081.56 738 3422464.91 151774.89 50 80 3425032.54 148010.78 6 122 3420456.87 144890.72 16 164 3413665.96 149412.28 2539 3427886.17 151630.98 61 81 3422891.55 148013.72 4 123 3423085.81 144743.25 8 165 3410313.67 153727.63 1340 3416666.19 151615.64 7 82 3412872.30 147855.93 35 124 3425944.13 144391.30 61 166 3415653.74 152134.73 441 3404677.30 151452.24 10 83 3415274.27 147855.11 5 125 3412567.68 144236.36 442 3414238.68 151461.81 7 84 3422907.90 147688.05 61 126 3413478.16 143906.34 6

UNIDENTIFED MAGNETIC ANOMALIES


LCA TERREBONNE BASIN

BARRIER SHORELINE

RESTORATION STUDY

ANNEX L-2

ISLAND DESIGN PLANS















































































LCA TERREBONNE BASIN

BARRIER SHORELINE

RESTORATION STUDY

ANNEX L-3

SUPPLEMENTAL MODELING

REPORTS


1

ANNEX L-3 SUPPLEMENTAL MODELING REPORTS

This Annex to the Terrebonne Basin Barrier Shoreline Restoration’s Engineering

Investigations and Cost Estimates report (Appendix L) describes procedures and results

of shoreline change analysis using the GENESIS model and storm-induced cross-shore

sediment transport analysis using the SBEACH model.

GENESIS is a widely accepted longshore sediment transport model utilized for

predicting long-term platform evolution of a beach in response to imposed wave

conditions as well as simulating beach fill diffusion and response to coastal structures.

The model’s use is considered standard practice both in the United States and

internationally as evidenced by the many documented applications in professional

journals and conference proceedings. The assumptions utilized in the modeling program

along with verification of use of the model are presented herein.

SBEACH is a widely accepted cross-shore sediment transport model utilized for

predicting storm-induced beach and dune erosion. The model’s use is considered standard

practice both in the United States and internationally as evidenced by the many

documented applications in professional journals and conference proceedings. The

assumptions utilized in the modeling program along with verification of use of the model

are presented herein.

1. GENESIS MODELING REPORT

1.1 EXECUTIVE SUMMARY

Raccoon Island and Whiskey Island, located in Terrebonne Parish, Louisiana, form the

western extent of the Isles Dernieres barrier island arc. These islands experience severe

shoreline erosion and retreat rates as a result of barrier island roll-over in response to

relative sea level rise, overwash during severe storm activity, wave-induced erosion,

inadequate sediment supply and anthropogenic influences. The performance of eight

detached segmented breakwaters constructed in 1997 at the eastern end of Raccoon

Island to mitigate erosion has generated interest in the potential usage of such coastal

protection measures in the restoration efforts currently being considered for other barrier

islands in the Terrebonne Basin.

Of immediate interest is an assessment of the impact specific shore protection measures

placed off of Raccoon and Whiskey Islands may have on the islands’ long-term erosion

problems. This report details shoreline change modeling based on a coupled

wave/shoreline change model undertaken to evaluate these specific management

measures. The Steady State Spectral Wave (STWAVE) model was used to transform

wave data from offshore locations to locations near the surf zone. The Generalized Model

for Simulating Shoreline Change (GENESIS) uses this information to simulate shoreline

change due to wave-driven longshore sediment transport. The model assumes that the

cross shore profile is in equilibrium, so that morphological change can be represented by

the change in shoreline position alone. The background shoreline change option in

GENESIS was utilized to simulate the long-term net aggregate effects of all cross-shore


2

processes which dominate the erosional processes experienced by the islands compared

to the longshore processes.

It was shown that GENESIS reasonably reproduced the medium to long-term erosion

trends observed on Raccoon and Whiskey Islands, and the response of the shoreline of

Raccoon Island after the placement of the system of breakwaters. The potential shoreline

responses to the placement of additional structural measures on Raccoon Island and

Whiskey Island in the future were evaluated. These structural measures included: a

terminal groin at the western end of Raccoon Island, and 19 detached segmented

breakwaters placed off of Whiskey Island. Both measures reduced the rate of shoreline

recession. The model results were utilized to assess the performance of the structures on

the evolution of habitat acres over time.

The complexity of the erosional and depositional processes at play in this environment

naturally dictates that numerical model results should be used with caution and in

conjunction with other empirical evidence. Additionally, the design of any engineering

project aimed at mitigating shoreline retreat on Whiskey Island and the other Terrebonne

Basin barrier islands will greatly benefit from the formation of a detailed sediment

budget. Lastly, due to the highly variable nature of the coastal processes within the

Terrebonne Basin and the limitations of modeling barrier island restoration performance

and response to structures with the GENESIS model as noted herein, it is recommended

that combined wave and current modeling be conducted in the Planning, Engineering,

and Design Phase (PED) on a system-wide level to support the National Ecosystem

Restoration (NER) Plan.

1.2 INTRODUCTION

The Terrebonne Basin Barrier Island system is a 40 mile long barrier island chain made

up of two island arcs: Isles Dernieres (Raccoon Island, Whiskey Island, Trinity/East

Island and Wine Island) and the Timbalier Islands (Timbalier Island and East Timbalier

Island) located in Terrebonne and Lafourche parishes. These islands have historically

experienced extensive shoreline retreat as a result of landward barrier migration in

response to relative sea level rise, episodic damage from tropical cyclones, sediment

starvation and anthropogenic influences. As part of the Raccoon Island Breakwaters

Demonstration project (TE-29; Armbruster, 1999), eight detached segmented breakwaters

were constructed in 1997 at the eastern end of Raccoon Island to reduce shoreline erosion

and promote accretion. These breakwaters are widely regarded as having fulfilled their

intended function due to rapid salient development behind most of the breakwaters and a

measurable decrease in the rate of shoreline retreat.

In 2005, a terminal groin was added to the eastern end of the island, and eight additional

breakwaters were constructed immediately west of the original eight structures (TE-48).

As a result of the performance of the 1997 breakwaters, there is interest in the potential

for using detached segmented breakwaters to assist in the restoration efforts currently

being considered for the six other Terrebonne Basin barrier islands. Of immediate interest

is an assessment of the impact segmented breakwaters placed offshore of Whiskey Island

may have on the Island’s long-term erosion problems and an assessment of the impact a


3

terminal groin placed at the western end of Raccoon Island may have on the continued

shoreline recession experienced west of the system of breakwaters.

This report details shoreline change modeling based on a coupled STWAVE/GENESIS

model undertaken to evaluate these specific management measures. The STWAVE

model transforms wave data from offshore locations to the surf zone. An initial effort was

made to evaluate the ability of GENESIS to reproduce the medium to long-term shoreline

change trends observed on Raccoon and Whiskey Islands, as well as to reproduce the

response of the shoreline of Raccoon Island to the placement of the initial set of offshore

breakwaters. Upon successful calibration and validation of GENESIS for these Islands,

the model was used to evaluate the potential shoreline response to: (1) the placement of

19 detached breakwaters in the nearshore region of Whiskey Island based on the design

parameters of the Raccoon Island breakwaters, and, (2) the placement of a terminal groin

at the western end of Raccoon Island.

1.3 GEOMORPHIC SETTING

Rosati and Stone (2009) provide an excellent review of the literature pertaining to the

formation and geomorphic evolution of barrier islands along the shoreline of the northern

Gulf of Mexico. A summary of that work is outlined below. The Terrebonne Basin

Barrier Island chain represents the erosional remnants of the abandoned Teche and

Lafourche deltas of the Mississippi River system. The formation of these barrier islands

occurs in four stages: (1) flow is redirected to a more efficient distributary, resulting in

the in-filling of the old delta with fine sediment, (2) the abandoned delta lobe undergoes

erosion and feeds flanking barrier islands, (3) this sediment source is depleted by waveinduced erosion and subsidence due to sediment compaction, (4) the barrier islands

retreat as they are reworked by inner shelf processes and their underlying substrate

consolidates and subsides.

There are three primary causes for the barrier islands to have experienced rapid erosion

and disintegration. The first cause is that the islands are not connected to any outside

sediment source and hence are starved of sediments. The second cause is the compaction

and subsidence of the underlying deltaic material, which results in a relative lowering of

the island profile due to the relative sea level rise. A final cause for the rapid land loss in

these islands is the impact of catastrophic storm activity which removes material from

both the Gulf-side and bay-side of the island chain, causes landward migration and also

exposes the underlying deltaic material to wave attack.

Cross-shore profiles on these shorelines exhibit a break in slope around the 2 to 3 meter

isobaths. Above this point, the profile is of the approximate form , and the

material is made up of sand with median grain size in the range 0.1-0.14 mm. Below this

point, the profile is distinctly flat and composed mostly of silts and clays. The islands

typically have low elevations and are washed-over during major storms; the morphologic

responses to the two major storm systems – cold fronts and hurricanes – are distinctly

different.


4

Campbell (2005) developed a conceptual morphodynamic model for the shoreline retreat

observed west of the Plaquemine-modern delta of the Mississippi River based on the

analysis of historical beach profiles. The underlying substrate of the island chain is made

up of mixed deltaic sediment (sand, silt, and clay); this material is covered by a thin

veneer of sand which is eroded during storms, exposing the underlying marsh sediment.

In the aftermath of major storms, this exposed material is subsequently eroded by wave

action. Fine sediment is suspended and lost from the littoral system. Coarser material is

either transported offshore or alongshore, ending up in tidal inlets to be transported into

the bays behind the islands. Inlet formation plays a major role in the landward migration

of the islands, for example, inlets facilitate cross-shore movement of sediment through

ebb/flood shoal formation.

1.4 DESCRIPTION OF NUMERICAL MODELS

1.4.1 Steady State Spectral Wave (STWAVE) Model

Wave information immediately outside of the surf zone is required as input for the

longshore sediment transport and shoreline change estimates. Typically, wave

information is only available at offshore locations and this information must be

transformed to the edge of the surf zone for use by GENESIS. STWAVE was used in this

study to perform this wave transformation.

STWAVE is a steady-state, phase-averaged spectral wave model for the simulation of

wind-wave growth and propagation in arbitrary depths. The model simulates wind-wave

growth, refraction and shoaling due to both bathymetric features and currents, depth- or

steepness-limited wave breaking, wave diffraction, wave-wave interactions and whitecapping by solving the spectral action balance equation along backward traced rays

(Smith et al., 2001).

The spectral action balance equation is of the form (Smith et al., 2001):

   a ga a ga cos , cos ,  ga ga x y r rr

CC E f CC E f S C C

x y

   

 


 
    	

  
  
 
    [1]

where is absolute wave group celerity; denote x and y components

respectively; is absolute wave celerity; is the current direction; is the

propagation direction of a spectral component; is the spectral energy density; is the

frequency of spectral component; is the relative angular frequency; and represents

energy sources and sinks (i.e. momentum from winds, losses from whitecapping or

breaking, etc.). Numerical solution of the spectral action balance equation is achieved

using a finite difference scheme formulated on a Cartesian grid system.

In the surf zone, the maximum wave height is limited by water depth and wave steepness

based on the Miche criterion (Smith et al., 2001):


5

[2]

where is the zero-moment wave height, is wavelength, is wave number, and

is the total water depth. The STWAVE model assumes: mild slope and limited wave

reflection; steady-state waves, currents, and winds; linear refraction and shoaling; depthuniform current; negligible bottom-friction; and linear radiation stress. Model input

required for the shoreline change application are bathymetry, model grid and offshore

directional wave spectrum at the open ocean boundary (Smith et al., 2001). The

transformed wave conditions are stored at nearshore locations for use by GENESIS.

1.4.2 Generalized Model for Simulating Shoreline Change

(GENESIS)

GENESIS belongs to the class of shoreline change models known as one-line models.

The underlining assumption is that the cross-shore beach profile does not change with

time, so that the active profile only moves parallel to itself. Assuming that the cross-shore

profile is in long-term equilibrium (i.e. cross-shore movement of sediment averages out

over time), the rate of shoreline change ( 
 
 y t ) is simply a function of the variation in

longshore sediment transport ( 
 
 Q x ). It follows from the principle of mass conservation

(Hanson, 1989) that:

[3]

where is the depth of closure, is the berm height, and accounts for sediment

sources and sinks.

In GENESIS, the longshore transport rate (Q ) is parameterized on breaking wave

conditions as follows (Hanson, 1989):

[4]

where is the breaking wave height; is the wave celerity; denotes breaking wave

conditions, is the dominant wave direction, and and are dimensionless

coefficients given by:


6

where and are empirical constants, is the density of sand, is the density of

water, is the porosity of sand and is the average slope of the active beach profile.

In a coupled STWAVE/GENESIS application, GENESIS receives wave height and wave

direction information at the edge of the surf zone. This wave information is transformed

by internal wave transformation routines in GENESIS to the point of breaking using

Snell’s law. Since the model assumes an equilibrium profile, the basic inputs required for

running GENESIS are an initial shoreline position, the average height of the beach berm,

the depth of closure and the effective grain diameter which are used to define an

equilibrium profile.

1.5 DATA

1.5.1 Historical Shorelines

The Barrier Island Comprehensive Monitoring (BICM, Martinez, 2004) project provides

a comprehensive dataset of shoreline change data covering the period 1855 to 2005 based

on the analysis of historical maps, aerial photography and satellite imagery.

Quantification of shoreline change patterns and rates of change were conducted based on

shore perpendicular transects spaced at 50 meter intervals using the high-water line as the

official shoreline. The average historical (1855-2005) shoreline change rate for the

Louisiana Coastal Zone was -2.7 m/yr. Over the past decade this rate has accelerated to -

8.2 m/yr; the impacts of Hurricanes Katrina and Rita accelerated the rate of retreat to -

57.8 m/yr between 2004 and 2005 (BICM Task Order 3). The BICM dataset is primarily

based on four time periods: 1855-2005, 1920-2005, 1996-2005 and 2004-2005. Because

of the inadequate temporal resolution of this dataset pre-1996, additional historical

shoreline data for 1978, and 1989 was taken from Thompson et al. (2004).

1.5.2 Wave Climate

Wave data was sourced from the Wave Information Studies (WIS) conducted by the

Coastal Hydraulics Laboratory (CHL) and Engineer Research and Development Center

(ERDC), Vicksburg, Mississippi. WIS data provides directional wave climate

information for shorelines of the Gulf of Mexico based on a 20 year hindcast using the

2nd generation wave model WISWAVE. The current hindcast covers the period 1980 to

1999, and provides hourly hindcasts of the significant wave height, peak spectral period

and the dominant wave direction. No collocated wave buoys were found in the vicinity of

the Study area for estimation of the model skill of the WISWAVE hindcasts. Several

WIS stations were located in the vicinity of the Isles Dernieres. Figure 1-1 shows wave

rose diagrams of the directional distribution of wave heights at six WIS stations offshore

of the Raccoon and Whiskey Islands. Figure 1-2 shows the locations of the WIS stations.


7

A visual inspection of the wave roses shows very little difference in wave climate,

especially with respect to the angles of incidence of the large wave energy bands.

Sensitivity tests using each of these data confirmed that using different WIS stations from

the area resulted in similar estimates of longshore transport rates. WIS Station 125 was

chosen to provide offshore wave data for this work because it sits in a location which is

closest to the center of the study area.


8

Figure 1-1. Wave rose diagrams showing the directional distribution of significant wave

heights at WIS hindcast stations immediately offshore of Isles Dernieres. The distributions

of wave heights in the various directional bins are similar. Each of the six WIS datasets

predicts similar longshore sediment transport rates (source: http://frf.usace.army.mil/cgibin/wis/atl/atl_main.html).


9

-91.2 -91.0 -90.8 -90.6 -90.4

28.5

28.6

28.7

28.8

28.9

29.0

29.1

29.2

29.3

Longitude

Latitude



  





	

Figure 1-2. STWAVE model domain (dashed lines) showing the location of WIS stations.

Station 125 was used to provide offshore wave boundary conditions for STWAVE model

runs.


10

1.5.3 Bathymetry

Bathymetric information for the areas surrounding Raccoon and Whiskey Islands was

taken from the 2006 BICM survey data. These data provide dense nearshore profiles in

addition to survey information which extends 4 to 5 miles offshore of the islands in some

instances. Despite this coverage, bathymetric data even further offshore was needed for

use in the wave transformation calculations between WIS Station 125 and the nearshore

area.

Bathymetric data further offshore was sourced from depth soundings available in

electronic format from the Geophysical Data System (GEODAS). The GEODAS

database is maintained by the National Geophysical Data Center (NGDC) of the National

Ocean Survey (NOS). The data available offshore of the study area comes from two data

sets, both of which are dated from the late 1930’s. Despite the age of the data, in the

absence of another source these represent the only option available. A majority of this

data falls in depth of 40 feet or more which is well outside of the typical sediment

transport zone. As a result the primary difference in elevation between the data from the

1930’s and 2006 is expected to be due primarily to changes in relative sea level described

in Section L2.7 of Appendix L. Based on the sea level change rates, the GEODAS

bathymetry was lowered by 2.2 feet. Merging this adjusted offshore bathymetry with the

BICM nearshore data resulted in a single seamless 2006 bathymetry set which was used

for all simulations discussed below.

1.5.4 Beach and Sediment Transport Characteristics

Stone and Zhang (2001) made empirical estimates of longshore transport rates based on

nearshore wave information obtained through numerical wave modeling. A detailed

sediment budget study for Raccoon Island was conducted by Thompson et al. (2004)

using an analytical morphologic model. In this study, volumetric changes at closely

spaced transects on the island were estimated using the observed cross-shore changes in

beach profile and estimates of shoreline retreat due to relative sea level rise, and the

active profile height. Based on conservation of sand principles, the net longshore

transport was estimated by summing volumetric changes in the direction of the net littoral

drift, starting at a nodal point. Georgiou et al. (2005) also developed longshore sediment

transport estimates in coastal Louisiana.

Although the other two referenced studies (Stone and Zhang, 2001 Georgiou et al., 2005)

provided qualitative estimates of longshore transport, estimates of the depth of closure,

berm height, and the effective grain size for this modeling report were taken from

Thompson et al. (2004). These values were 1.8 m, 1.2 m and 0.14 mm respectively.

1.6 MODEL SETUP

1.6.1 STWAVE Model Setup

The coupled STWAVE/GENESIS model was setup in NEMOS (Nearshore Evolution

Modeling System). NEMOS provides a GIS-based user interface which allows for the


11

efficient generation of both STWAVE and GENESIS model grids and the preparation of

model input files. The merged BICM-GEODAS bathymetric dataset was imported and

triangulated in NEMOS, after which a uniform computational grid was generated. The

open ocean boundary of the STWAVE grid was located in proximity to the WIS stations,

eliminating the need for 1D wave transformations from WIS station locations to the wave

model’s open ocean boundaries.

Figures 1-2 and 1-3 show the extent of the STWAVE model grid and the model

bathymetry, respectively. No direct wave measurements coincident with the period of

record of the WIS data could be located in the model domain for model calibration and

validation. Instead, a sensitivity analysis for grid convergence was performed to ensure

that the numerical solution was independent of the grid resolution.

A sensitivity analysis was conducted using grid resolutions of 400x400 m, 200x200 m,

100x100 m, and 50x50 m. The 200x200 m grid provided the optimum balance between

numerical convergence and computational cost. The final STWAVE grid has 71,176 cells

(328 cells in the shore normal direction and 217 cells in the shore perpendicular

direction). Because it is impractical to run STWAVE at each shoreline simulation time

step, the typical STWAVE/GENESIS application utilizes a time saving procedure in

which offshore wave conditions are binned into wave height, wave period and wave

direction bands. Combinations of these wave conditions are transformed to nearshore

locations at which refraction coefficients are determined for each height-period-direction

combination. For every time step in the shoreline simulation, GENESIS applies a unique

refraction coefficient for each offshore wave event, which is determined as the ratio of

the offshore wave height to the transformed wave height. The WIS data used in this study

was binned into wave height, wave period, direction bands with widths of 2 meters, 3

seconds, 15 degrees, respectively, resulting in a total number of 300 combinations.

Figures 1-4 and 1-5 show the frequency distributions of the significant wave heights, and

peak wave periods, respectively.


12

Easting (m, UTM Zone 15)

Northing (m, UTM Zone 15)

680000 690000 700000 710000 720000 730000 740000

3185000

3190000

3195000

3200000

3205000

3210000

3215000

3220000

3225000

-18

-16

-14

-12

-10

-8

-6

-4

-2

0

2

Figure 1-3. STWAVE model bathymetry (meters) obtained by triangulation of the merged

BICM-GEODAS datasets onto a uniform grid.

0 1 2 3 4 5 6 7 8 9 0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Significant Wave Height (m)

Relative Frequency

Figure 1-4. Relative frequency of significant wave heights offshore of Raccoon Island and

Whiskey Island based on the 20-yr WIS hindcast at station 125. The wave height has a

mean value of 0.81 m, with a standard deviation of 0.41 m. The 50-yr (2% annual

exceedance probability) wave height is 8.1 m based on a Weibull distribution fit.


13

2 4 6 8 10 12 14 16 0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Peak Wave Period (sec)

Relative Frequency

Figure 1-5. Relative frequency of peak wave periods offshore of Raccoon Island and

Whiskey Island based on the 20-yr WIS hindcast at station 125.

1.6.2 GENESIS Model setup

The one-dimensional grid required by GENESIS was setup in NEMOS. The GENESIS

grid consists of a one-dimensional array of cells along the shoreline; the shoreline is

represented as distances from a straight baseline. At each cell and for each simulation

time step, the model requires breaking wave height and wave angle information to

compute a spatially and temporally varying longshore transport rate. In NEMOS,

STWAVE output stations corresponding to GENESIS grid cells can be automatically

generated based on some user specified water depth. These stations were typically

located on the 2 meter isobath. The average berm height was specified as 1.2 m and the

depth of closure was specified as 1.8 m. These values are based on beach profile survey

data contained in Thompson et al. (2004).

There is general consensus in the literature (Rosati and Stone, 2009) that the depth of

active sand transport on the Louisiana barrier islands to the west of the modern delta lies

in the ~2 to 3 m range. Beyond this point lies a passive depositional zone which is

typically very flat and composed of silts and clays separated from material eroded from

the islands when they had been stripped of sand cover in the aftermath of major storm

activity. This range of values is smaller than the ~5 m depth of closure predicted by

empirical equations (e.g. Birkemeier, 1985) given the wave climate at the study site. The

1.8 m value was used in this study because it is the actual measured depth of closure at

the site. Additionally, the net longshore flux computed by Thompson et al. (2004),

against which the current shoreline model has been calibrated, is based on this value. The

effective grain diameter was specified as 0.14 mm based on sieve analysis of grab

samples taken on Raccoon Island.


14

1.7 MODEL CALIBRATION AND VALIDATION

In order to quantify the potential shoreline response to the structural measures proposed

for Raccoon Island and Whiskey Island, a three-stage calibration and validation process

was undertaken. The approach is outlined below as follows:

a coupled STWAVE/GENESIS model was setup and calibrated for Raccoon

Island for a period preceding the initial construction of breakwaters (1978-1989);

a coupled STWAVE/GENESIS model was setup for Raccoon Island for a period

post-construction of the first eight demonstration breakwaters (1996-2004). The

sediment transport parameters were carried over from the initial calibration period

without adjustment;

finally, a coupled STWAVE/GENESIS model was setup for Whiskey Island

using the model setup and sediment transport parameters carried over from the

Raccoon Island simulations.

In the initial calibration runs (1978-1989), the sediment transport parameters ( and )

were adjusted till the model reproduced: the net longshore transport rate

( ); the average shoreline retreat rate due to longshore sediment loss

( ) – based on the littoral budget computed by Thompson et al. (2004); and, the

correct direction of net littoral drift (westward). Since GENESIS only explicitly simulates

shoreline change due to longshore transport, which according to the sediment budget

accounts for about 34% of the shoreline change observed on Raccoon, the background

shoreline change option in GENESIS was utilized to simulate the remainder of the

shoreline change (66%) not explicitly accounted for in the model. The background

change rate represents the long-term net aggregate effects of all cross-shore processes.

The background change option moves the shoreline backwards (or forwards if desired) at

a user specified rate (meters/day). The WIS data used for this simulation covered the

period 1980 to 1990.

For the model validation period for Raccoon Island (1996-2004), the simulation runs

were made using the initial shoreline (1996) and the initial set of TE-29 breakwaters. The

sediment transport parameters and basic GENESIS model setup was carried over from

the calibration runs. Since the shoreline at the eastern end of Raccoon is curved, the

easternmost two breakwaters could not be represented in the model. Additionally, the

curved portion of the island acts as a headland, producing diffracted waves; this conflicts

with GENESIS’ structure placement rules, which do not allow for the placement of

overlapping diffracting structures. For this reason the next two breakwaters could also not

be represented in the model. A workaround this problem would have been be to

artificially foldout the eastern portion of the island, this option was ruled out because a

straightened shoreline would misrepresent incident wave angles – and hence sediment

transport rates would not be accurately predicted.

The coordinates of the start and end points of the breakwaters were digitized from

rectified aerials and directly imported into GENESIS. The remaining breakwaters on

Raccoon Island were placed 91.44 m from the shoreline, they were 91.44 m long, and had


15

91.44 m wide gaps in between breakwaters. As reported by several authors (e.g. Stone

and Liu, 2006; Armbruster, 1999), the accretion observed leeward of the demonstration

set of breakwaters was largely due to the impoundment of cross-shore sediment drift

from nearby shoals (see Figures 1-6 and 1-7). Since GENESIS does not explicitly allow

for the specification of sediment sources or sinks, this effect was simulated by

introducing sediment into the model via the beach fill option as recommended by Hanson

and Kraus (1989). The volume of sand impounded behind the breakwaters was computed

as the product of the active profile height and the berm width added per day over the

simulation period. In the absence of this impoundment of sand, the model shows very

little accretion landward of the breakwaters.

Figure 1-8 shows plots for simulated versus observed shoreline positions for the end

position of the initial calibration period. Figure 1-9 shows plots for simulated versus

observed shoreline positions for the end shoreline position for the first validation period.

Finally, the validation procedure was repeated for Whiskey Island for the period 1996-

2004. Figure 1-10 shows plots for simulated versus observed shoreline positions for the

end shoreline position for the second validation period. In Figure 1-11, the validation

runs were repeated with the regional offshore contour option in GENESIS. This option

assumes that the depth contours in the surf zone are similar to the initial shoreline

orientation. This option however resulted in sediment transport rate predictions that were

unreasonably low. Table 1-1 shows a compilation of model setup parameters for all three

calibration/validation periods. A quantitative assessment of model skill based on cell by

cell comparisons between simulated and observed shorelines is provided in Table 1-2.

Figure 1-6. August 1999 photograph showing the response of the demonstration

breakwater field to breakwater construction. Note the width of the salients after two years

compared with the width of the beach formed in the vicinity of the breakwaters

(Armbruster, 1999).


16

Figure 1-7. Nearshore bathymetry around Raccoon Island showing offshore shoals around

the eastern tip of the island (Armbruster, 1999).

Figure 1-8. GENESIS model results for the initial calibration period 1978-1989 showing

observed and simulated shorelines for Raccoon Island.


17

Figure 1-9. Validation of the Raccoon model for the period 1996-2004 illustrating the

model’s ability to capture the response of the shoreline after the placement of the initial set

of eight demonstration breakwaters. The eastern end shows erosion instead of the observed

accretion because the breakwaters could not be represented in the model due to the

orientation of the shoreline at that end.

Figure 1-10. Validation of the GENESIS model setup for Whiskey Island. The simulated

shoreline is smooth because of the hand-off of STWAVE information to GENESIS outside

of the surf zone where the depth contours are almost straight and parallel.


18

Figure 1-11. Repeat of the Whiskey Island validation runs assuming that the orientation of

the initial shoreline is representative of offshore contour lines in the surf zone. This option

in GENESIS resulted in erroneous transport rates and hence was not used.

Table 1-1. GENESIS Model Setup Parameters

Parameter Raccoon Island

1978 – 1989

Raccoon Island

1996 – 2004

Whiskey Island

1996 – 2004

Number of cells 225 170 225

Cell width 30 m 30 m 20 m

Simulation time step 1 hr 1 hr 1⁄4 hr

Left lateral boundary

condition -0.037 m/day -0.037 m/day -0.037 m/day

Right lateral boundary

condition -0.062 m/day -0.062 m/day -0.013 m/day

Background retreat rate -7 m/yr -9 m/yr -9 m/yr

Median grain size 0.14 mm 0.14 mm 0.14 mm


19

Parameter Raccoon Island

1978 – 1989

Raccoon Island

1996 – 2004

Whiskey Island

1996 – 2004

Berm height 1.2 m 1.2 m 1.2 m

Depth of closure 1.8 m 1.8 m 1.8 m

K1 0.02 0.02 0.02

K2 0.02 0.02 0.02

Number of breakwaters 0 4 0

Table 1-2. Summary of Model Skill Indicators.

Raccoon Island

Model

1978 – 1989

Raccoon Island

Model

1996 – 2004

Whiskey Island

Model

1996 – 2004

Average Error 1.20 m/yr 2.12 0.81 m/yr

Maximum Error (+) 2.05 m/yr 7.03 20.54 m/yr

Minimum Error (-) -4.29 m/yr -6.82 -24.04 m/yr

Root Mean Squared

Error 1.94 m/yr 3.89 7.78 m/yr

1.8 PERFORMANCE OF STRUCTURAL MEASURES

1.8.1 Detached Breakwaters off of Whiskey Island

In order to assess the potential response of the shoreline to the future placement of

breakwaters off of Whiskey Island, nineteen breakwaters were inserted into the 2005

shoreline and a shoreline change simulation was run for an eight year period terminating

in 2012. The design parameters for the breakwaters on Whiskey Island were based on the

structural configuration of the TE-29 breakwaters on Raccoon Island. Since GENESIS

only accounts for longshore sediment transport, there was a need to apply a background

shoreline change rate reflecting the long-term average effects of overwash, aeolian and

other cross-shore transport processes that do not average-out long-term as assumed in the

formulation of the GENESIS model. Following Thompson et al. (2004), this residual

retreat was estimated to be 50% of the original long-term cross-shore transport related

shoreline change rate in Table 1-1. Figure 1-12 shows the initial and final positions of the

Whiskey Island shoreline for the simulation period. Tables 1-2 and 1-3 provide

summaries of error estimates and shoreline change rates, respectively.


20

Figure 1-12. Simulated shoreline change on Whiskey Island assuming the placement of

detached segmented breakwaters (lengths, gap widths, and distance from shore all

approximately 92 m).

Table 1-3. Summary of shoreline change rates. Note that the rates for Raccoon

Island do not include any background (cross-shore transport-related) shoreline

change rates.

Shoreline Change Rate (m/yr)

Whiskey Island Raccoon Island

Without structure -13.82 -2.45

With structure -8.2 -1.65

1.8.2 Terminal Groin at Western End of Raccoon Island

The potential response of the shoreline to the placement of a terminal structure at the

western end of Raccoon Island was also evaluated. The terminal groin is aimed at

intersecting the net longshore sediment flux, thereby retaining sediment on the beach

updrift of the groin. The length of the groin from the beach to the seaward tip was set to

approximately 365 meters. This structural measure was evaluated by running an eight

year shoreline change simulation starting in 2005 and terminating in 2012. The shoreline

responses in the absence and presence of a terminal groin on Raccoon Island are depicted

in Figures 1-13 and 1-14, respectively. Tables 1-2 and 1-3 provide summaries of error

estimates and shoreline change rates, respectively.


21

Figure 1-13. Raccoon Island simulation (2005-2012) without any background shoreline

change imposed. Model setup includes all TE-48 breakwaters and two TE-29 breakwaters.

Figure 1-14. Same as Figure 1-14 with the exception of a terminal groin placed near the western end

of Raccoon Island.


22

1.9 CONCLUSIONS

GENESIS reasonably reproduced shoreline change trends observed on the Isles Dernieres

for the years 1978 to 1989 and 1996 to 2004 on Raccoon Island, and for the years 1996 to

2004 on Whiskey Island. The calibrated model results were used to evaluate the potential

performance of proposed structural measures aimed at mitigating sediment loss and

shoreline recession on Raccoon and Whiskey Islands. These measures included a

terminal groin at the western end of Raccoon Island and a system of detached

breakwaters off of Whiskey Island. The model results showed that shoreline erosion and

retreat will be mitigated with the proposed structural measures.

GENESIS only explicitly accounts for longshore sediment transport, which is only of

secondary importance (Rosati and Stone, 2009, Thompson et al., 2004) as far as sediment

transport mechanisms responsible for shoreline erosion and retreat on the islands are

concerned. Other sediment transport mechanisms are only treated in the model in terms

of long-term average background change rates. Additionally, the erosional and

depositional processes at play on these barrier islands are complex, and no single process

controls or explains the geomorphologic response of the islands to external forcing.

Therefore the model results, when applied to engineering design and the evaluation of

alternative shore protection measures, should be treated with care. For example, it will be

beneficial to evaluate the historical response of breakwater protected shorelines to

episodic but catastrophic events such as the passage of severe tropical cyclones. Further,

it is recommended that combined wave and current modeling be conducted in PED on a

system-wide level to support the NER Plan.

Due to the small net longshore flux on these islands (an average of 40,000 cubic meters

per year; Rosati and Stone, 2009) and the possibility of adverse downdrift impacts,

optimum project designs should include beach nourishment.

2. SBEACH MODELING REPORT

2.1 SBEACH MODEL DESCRIPTION

SBEACH (Storm-induced BEAch CHange) was developed at the U.S. Army Engineer

Waterways Experiment Station, Coastal and Hydraulics Laboratory (CHL), to calculate

beach and dune erosion under storm water levels and wave action (Larson and Kraus

1989; Larson, Kraus, and Bymes 1990; Rosati et al. 1993). Model development was

based on extensive analysis of beach profile change produced in large wave tanks and in

the field. It is a two-dimensional model meaning that longshore wave, current, and

sediment transport processes are omitted. Breaking waves and changing water level are

the major driving agents in SBEACH that produce sediment transport and beach profile

change.

SBEACH has significant capabilities that make it useful for quantitative and qualitative

study of beach profile response to storms. It accepts as input varying water levels as


23

produced by storm surge and tide, varying wave heights and periods, and an arbitrary

grain size in the fine-to-medium sand range. Either a user-specified schematic dune and

berm configuration or a surveyed profile configuration can comprise the initial profile.

2.2 SBEACH INPUT

SBEACH requires several inputs: profile configuration, time series of wave parameters

(wave height, period and direction), and time series of water elevation. The user must

also specify sediment size, grid spacing, time step, and other parameters.

Because Hurricanes Katrina and Rita occurred in August-September of 2005 within 25

days they were combined in one storm event. Similarly, because Hurricanes Gustav and

Ike occurred in September 2008 within 11 days of each other, they were also combined in

one storm event.

For the Katrina-Rita and Gustav-Ike SBEACH simulations, water elevation time series

were obtained from verified historical records at NOAA/NOS CO-OPS Station 8761724

located at the Coast Guard Station on Grand Isle. Wave and wind data were acquired

from the NOAA/NWS/NCEP operational ocean wave predictions based on the output

from the WAVEWATCH III model (http://polar.ncep.noaa.gov/waves/index2.shtml).

The wave and wind data were obtained at the WIS-125 location (LAT=28.58N,

LON=90.75W) in approximately 60-foot deep water.

The STWAVE model was used to propagate the wave conditions at WIS-125 to the

offshore SBEACH boundary located approximately 8,000 feet seaward of the barrier

shoreline in approximately 14-foot deep water. Figures 2-1 and 2-2 present wave height,

wave period, and water elevation used in the SBEACH simulations of Katrina-Rita and

Gustav-Ike, respectively.


24

Day (2005)

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

0

2

4

6

8

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27 Sep. 6 Sep. 1 Sep. 26

no water level data

Katrina

Rita

Sep. 11 Sep. 16 Sep. 21

Hurricanes Katrina and Rita (2005)

at SBEACH Offshore Boundary

Figure 2-1. Hurricanes Katrina-Rita wave/water level input information used in SBEACH.


25

Day (2008)

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

0

2

4

6

8

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27 Sep. 6 Sep. 1 Sep. 11

Hurricanes Gustav and Ike (2008)

at SBEACH Offshore Boundary

no water level data

Gustav

Ike

Figure 2-2. Hurricanes Gustav-Ike wave/water level input information used in SBEACH.

Figures 2-3 and 2-4 present wind speed used in the SBEACH simulations of Katrina-Rita

and Gustav-Ike, respectively.


26

Day (2005)

Wind Speed (mph)

0

10

20

30

40

50

60

70

80

Wind Speed

Katrina

Rita

Hurricanes Katrina and Rita (2005)

at SBEACH Offshore Boundary

Aug. 27 Sep. 1 Sep. 6 Sep. 11 Sep. 16 Sep. 21 Sep. 26

Figure 2-3. Hurricanes Katrina-Rita wind speed used in SBEACH.


27

Day (2008)

Wind Speed (mph)

0

5

10

15

20

25

30

35

40

45

50

55

60

Wind Speed

Ike

Gustav

Aug. 27 Sep. 1 Sep. 6 Sep. 11

Hurricanes Gustav and Ike (2008)

at SBEACH Offshore Boundary

Figure 2-4. Hurricanes Gustav-Ike wind speed used in SBEACH.

The 50-year hypothetical storm was created based on the analysis of extreme wave

conditions obtained at WIS-125 station and extreme storm surge statistics at Grand Isle.

Based on the extreme wave analysis, a 50-year storm at the WIS-125 location would

produce 27-foot high waves at the peak of the storm with a period of 13.2 seconds.

According to USACE (1979), a surge elevation at Grand Isle that corresponds to the 50-

year return interval is 8.5 feet. Because this is a hypothetical storm, a time series of wave

height and water elevation that occurred during Hurricane Katrina (2005) was used to

create a time series of wave height and water elevation for the 50-year storm. The

Hurricane Katrina wave height and water elevation time series were proportionally

adjusted to match the peak 50-year storm wave height and water elevation. Figure 2-5

presents the wave height, wave period, and water elevation used in the STWAVE model

to propagate the 50-year storm from the WIS-125 location to the SBEACH offshore

boundary. Figure 2-6 presents the wave height, wave period, and water elevation used in

the SBEACH simulation of the 50-year storm.


28

Day

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

25

30

35

40

45

50

0

2

4

6

8

10

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27

50-Year Storm at WIS-125

Sep. 1

Figure 2-5. 50-year storm wave/water level input information at WIS-125.


29

Day

Wave Height (ft), Wave Period (sec)

Water Level (NAVD88, ft)

0

5

10

15

20

0

2

4

6

8

10

Wave Height

Wave Period

Water Level (at Grand Isle)

Aug. 27

50-Year Storm

at SBEACH Offshore Boundary

Sep. 1

Figure 2-6. 50-year storm wave/water level input information used in SBEACH.

2.3 SBEACH RESULTS

SBEACH simulations were performed in order to determine the minimal barrier island

design parameters that retain barrier island’s geomorphic form and ecologic function

after being subjected to design storm including a combined storm event of Hurricanes

Katrina and Rita, a combined storm event of Hurricanes Gustav and Ike, and a

hypothetical 50-year storm.

Thirteen (13) dune/beach/marsh templates were designed in an iterative process to yield

the minimized restoration design template. Table 2-1 presents the design template

parameters which include dune/beach/marsh width and elevation. A typical profile based

on the 2006 BICM survey data of Whiskey Island was used to complete the template

seaward and landward of the restoration design template.


30

Table 2-1. Summary of Design Template Parameters Used in SBEACH Modeling

Template

Dune

Width,

ft

Dune

Elev.,

ft

NAVD

Gulfside

Beach

Width,

ft

Bayside

Beach

Width,

ft

Beach

Elev.,

ft NAVD

Marsh

Width,

ft

Marsh

Elev.,

ft NAVD

01 100 6 300 100 4 1000 1.6

02 100 6 400 100 4 1000 1.6

03 200 6 400 100 4 1000 1.6

04 100 6 250 100 4 1000 1.6

05 100 6 200 100 4 1000 1.6

06 100 6 150 100 4 1000 1.6

07 100 6 100 100 4 1000 1.6

08 100 6 50 100 4 1000 1.6

09 100 5.5 200 100 4 1000 1.6

10 100 6 250 100 3.8 1000 1.6

11 100 6 250 75 3.8 1000 1.6

12 100 6 250 100 3.5 1000 1.6

13 75 6 250 100 4 1000 1.6

Initially, each of the design templates was modeled using the 50-year storm parameters

and 0.16 mm grain size. Based on the results of these simulations, a decision was made

whether to continue to model the template applying the hurricane event conditions or to

screen out the template from future consideration.

For the screened templates, three grain sizes, 0.12 mm, 0.16 mm, and 0.20 mm, were

used in SBEACH simulations to account for variability in sediment sizes of potential

borrow sources.

Table 2-2 presents the SBEACH results of 50-year storm simulations expressed in terms

of shoreline recession at Mean High Water (MHW), maximum post-storm dune

elevation, dune overwash and, beach overwash. Based on the outcome of these

simulations, Templates 02, 03, 05, 06, and 08 were screened out and removed from

further analysis because the performance of comparable templates of smaller dimensions

met the required criteria to retain barrier island’s geomorphic form and ecologic function.


31

Table 2-2. Summary of 50-year Storm Simulations

Template

Dune

Elevation,

ft NAVD88

Erosion at

MHW,

ft

Dune

Overwash,

ft

Beach

Overwash,

ft

01 5.1 123 123 19

02 N/M* N/M N/M N/M

03 N/M N/M N/M N/M

04 5.3 123 120 25

05 N/M N/M N/M N/M

06 N/M N/M N/M N/M

07 4.8 120 118 33

08 N/M N/M N/M N/M

09 4.6 122 115 28

10 5.1 126 123 29

11 5.2 125 97 29

12 5.0 131 118 33

Sediment Size = 0.12mm

13 5.2 123 126 35

01 5.3 84 126 20

02 5.3 85 121 23

03 5.6 85 114 2

04 5.3 84 116 25

05 5.1 85 125 28

06 5.0 85 119 26

07 5.0 85 116 32

08 4.9 83 117 38

09 4.5 84 116 33

10 5.2 86 116 29

11 5.2 86 98 36

12 5.1 89 120 28

Sediment Size = 0.16 mm

13 4.9 84 111 25

01 5.3 51 121 21

02 N/M N/M N/M N/M

03 N/M N/M N/M N/M

04 5.2 51 123 22

05 N/M N/M N/M N/M

06 N/M N/M N/M N/M

07 5.0 51 118 34

08 N/M N/M N/M N/M

09 4.5 51 125 41

10 5.1 53 121 28

11 5.2 53 105 34

12 5.1 54 117 28

Sediment Size = 0.20 mm

13 5.0 51 120 28

*N/M denotes not modeled after template was screened out


32

All of the templates that passed the 50-year storm screening were further analyzed and

modeled using two combined storm events: 1) Hurricanes Katrina and Rita, and 2)

Hurricanes Gustav and Ike. Tables 2-3 and 2-4 present the SBEACH results expressed in

terms of shoreline recession at Mean High Water (MHW), maximum post-storm dune

elevation, dune overwash and, beach overwash, that occurred during the simulations of

Katina and Rita, and Gustav and Ike, respectively.

Table 2-3. Summary of Hurricanes Katrina and Rita Simulations.

Template

Dune

Elevation,

ft NAVD88

Erosion at

MHW,

ft

Dune

Overwash,

ft

Beach

Overwash,

ft

01 4.2 150 297 188

04 4.0 150 343 239

07 3.6 144 Dune Gone 271

09 3.7 149 Dune Gone 303

10 4.2 156 335 218

11 4.1 157 333 249

12 4.0 161 320 216

Sediment Size =0.12mm

13 4.0 148 362 261

01 4.7 106 301 190

04 4.0 104 345 235

07 3.7 102 Dune Gone 290

09 4.1 105 402 292

10 4.1 104 329 232

11 4.0 106 334 251

12 3.9 107 322 218

Sediment Size = 0.16mm

13 4.1 101 362 263

01 4.3 68 297 185

04 4.0 67 349 235

07 3.7 64 Dune Gone 307

09 3.7 65 Dune Gone 284

10 4.0 67 332 223

11 3.9 66 327 246

12 3.8 66 321 217

Sediment Size = 0.20mm

13 3.9 64 Dune Gone 268


33

Table 2-4. Summary of Hurricanes Gustav and Ike Simulations.

Template

Dune

Elevation,

ft NAVD88

Erosion at

MHW,

ft

Dune

Overwash,

ft

Beach

Overwash,

ft

01 4.1 116 294 188

04 4.0 116 344 236

07 3.6 116 Dune Gone 288

09 3.6 118 Dune Gone 282

10 4.0 118 333 219

11 3.9 118 336 243

12 3.8 126 322 218

Sediment Size =0.12mm

13 4.0 116 364 260

01 4.1 80 322 208

04 4.0 80 341 235

07 3.7 80 Dune Gone 251

09 3.8 81 Dune Gone 287

10 4.0 82 333 229

11 3.9 82 318 245

12 3.9 85 322 217

Sediment Size = 0.16mm

13 4.0 80 365 249

01 4.0 44 324 213

04 4.0 44 343 227

07 3.7 44 Dune Gone 270

09 3.7 44 Dune Gone 283

10 4.0 44 333 226

11 3.9 45 325 248

12 3.8 45 317 215

Sediment Size = 0.20mm

13 3.9 44 Dune Gone 252

Based on the results of these simulations, Templates 07, 09, 11, and 12 did not meet the

required criteria to retain the barrier island’s geomorphic form and ecologic function. Of

the remaining four templates that passed the screening criteria, Template 10 was

determined to be minimal and thus was selected as the design template.

2.4 MINIMAL DESIGN TEMPLATE PERFORMANCE

Figures 2-7 through 2-9 present comparisons between the pre-storm and post-storm

Template 10 (minimal design template) beach profiles computed for Hurricanes Katrina

and Rita, Gustav and Ike, and the 50-year design storm, using grain sizes of 0.12 mm,

0.16 mm, and 0.20 mm, respectively.


34

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: Katrina & Rita

Erosion at MHW = 156'

Max. Dune Elev. = 4.2' NAVD

Dune Overwash = 335'

Beach Overwash = 218'

mean grain size = 0.12 mm

MHW

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: Gustav & Ike mean grain size = 0.12 mm

MHW

Erosion at MHW = 118'

Max. Dune Elev. = 4.0' NAVD

Dune Overwash = 333'

Beach Overwash = 219'

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: 50-Year Storm

Erosion at MHW = 126'

Max. Dune Elev. = 5.1' NAVD

Dune Overwash = 123'

Beach Overwash = 29'

mean grain size = 0.12 mm

MHW

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Figure 2-7. Pre-storm (Initial) and Post-storm (Final) Template 10 Profiles using 0.12-mm

Grain Size.


35

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: Katrina & Rita

Erosion at MHW = 104'

Max. Dune Elev. = 4.1' NAVD

Dune Overwash = 329'

Beach Overwash = 232'

mean grain size = 0.16 mm

MHW

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: Gustav & Ike mean grain size = 0.16 mm

MHW

Erosion at MHW = 82'

Max. Dune Elev. = 4.0' NAVD

Dune Overwash = 333'

Beach Overwash = 229'

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: 50-Year Storm

Erosion at MHW = 86'

Max. Dune Elev. = 5.2' NAVD

Dune Overwash = 116'

Beach Overwash = 29'

mean grain size = 0.16 mm

MHW

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Figure 2-8. Pre-storm (Initial) and Post-storm (Final) Template 10 Profiles using 0.16-mm

Grain Size.


36

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: Katrina & Rita

Erosion at MHW = 67'

Max. Dune Elev. = 4.0' NAVD

Dune Overwash = 332'

Beach Overwash = 223'

mean grain size = 0.20 mm

MHW

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: Gustav & Ike mean grain size = 0.20 mm

MHW

Erosion at MHW = 44'

Max. Dune Elev. = 4.0' NAVD

Dune Overwash = 333'

Beach Overwash = 226'

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Distance Along Profile (ft)

Elevation (ft, NAVD88)

5000 6000 7000 8000 9000 10000 11000

-10

-5

0

5

10

Initial

Final

Template 10: 50-Year Storm

Erosion at MHW = 53'

Max. Dune Elev. = 5.1' NAVD

Dune Overwash = 121'

Beach Overwash = 28'

mean grain size = 0.20 mm

MHW

Dune 100' wide, 6' NAVD

Gulfside Beach 250' wide, 3.8' NAVD

Bayside Beach 100' wide, 3.8' NAVD

Marsh 1000' wide, 1.6' NAVD

Figure 2-9. Pre-storm (Initial) and Post-storm (Final) Template 10 Profiles using 0.20-mm

Grain Size.

Because pre- and post-storm survey data for the Terrebonne Islands were not available

the SBEACH model was not calibrated and default sediment transport model parameters

were used including:

Transport rate coefficient = 1.75*10-6 m4/N

Overwash transport parameter = 0.005

Coefficient for slope-dependent term = 0.002 m2/S

Transport rate decay coefficient multiplier = 0.5

However, model results were verified using shoreline erosion rates estimated based on

aerial photographs taken in 2004 and 2005 during which Hurricanes Katrina and Rita

occurred. OCPR (2008) reported 181.4 feet of erosion and 124.3 feet of erosion on

Whiskey Island and on the Isles Dernieres island chain, respectively. Taking into

account historic erosion rates presented in Appendix L, Section L3.2, 42.7 feet per year


37

for Whiskey Island and 37 feet per year for the Isles Dernieres island chain, the

magnitude of erosion resulting from the two hurricanes was 138.7 feet and 87.3 feet for

Whiskey Island and the Isles Dernieres island chain, respectively. The range of erosion

caused by the combined Katrina and Rita event computed by SBEACH was between 67

feet (upper grain size limit = 0.20 mm) and 156 feet (lower grain size = 0.12 mm).

Therefore, the estimated magnitude of erosion falls within the erosion range computed by

SBEACH and thus verifies model results and justifies using the SBEACH model.

3. REFERENCES

Armbruster, C.K. 1999. Raccoon Island Breakwater TE-29, Monitoring Progress Report.

Louisiana Department of Natural Resources, Coastal Restoration Division. Monitoring

Theories No. TE-29-MSPR-0899-1. 24 pp. plus appendix.

Birkemeier, W. 1985. Field data on seaward limit of profile change. Journal of

Waterway, Port, Coastal and Ocean Engineering, 111 (3), 598-602.

Campbell, T. 2005. Development of a conceptual morphosedimentary model for design

of coastal restoration projects along the Louisiana coast. Journal of Coastal Research (44)

234-244.Georgiou, I.Y., Fitzgerald, D.M., and Stone, G.W., 2005. The Impact of

Physical Processes along the Louisiana Coast. Journal of Coastal Research, SI(44), 72–

89. West Palm Beach (Florida), ISSN 0749-0208.

Hanson, H., N. C. Kraus. 1989. GENESIS: Generalized model for simulating shoreline

change, Report 1, Technical reference. Technical Report CERC-89-19. Vicksburg, MS:

U.S. Army Engineer Waterways Experiment Station, Coastal Engineering Research

Center.

Rosati, J.D., Stone, G.W. 2009. Geomorphic Evolution of Barrier Islands along the

Northern U.S. Gulf of Mexico and Implications for Engineering Design in Barrier

Restoration. Journal of Coastal Research 25 (1): 8-22.

Martinez, L. 2006. BICM Task Order 3: Shoreline Change Analysis. University of New

Orleans, Pontchartrain Institute for Environmental Sciences, New Orleans, Louisiana.

Office of Coastal Protection and Restoration (OCPR). 2008. 2008 Operations,

Maintenance, and Monitoring Report for Whiskey Island Restoration State Project

Number TE-27.

Smith, J.M., Sherlock, A.R., Resio, D.T. 2001. Steady-State Spectral Wave Model:

User’s Manual for STWAVE Version 3.0. USACE Engineer Research and Development

Center, Vicksburg, Mississippi.

Stone, G.W., Wang, P., Armbruster, C.K. 1999. Unanticipated response to detached,

segmented breakwaters along Raccoon Island, Louisiana. Proceedings of the 4th

International Symposium on Coasting Engineering and Science of Coastal Sediment

Processes held in Hauppauge, New York, June 21-23, 1999.


38

Stone, G.W., Zhang, X. 2001. A longshore sediment transport model for the Timbalier

Islands, Louisiana. Baton Rouge, Louisiana: Coastal Studies Institute Louisiana State

University.

Thompson, G. G., Campbell, J.T., Mann, D.W. 2004. Raccoon Island Project (TE-48)

Sediment Budget. Terrebonne Parish, Louisiana.



LCA TERREBONNE BASIN

BARRIER SHORELINE

RESTORATION STUDY

ANNEX L-4

MCACES COST ESTIMATES FOR

THE NER PLAN AND FIRST

COMPONENT OF

CONSTRUCTION


LCA Terrebonne Basin Barrier Shoreline Restoration

National Ecosystem Restoration Plan MCACES Estimate

Introduction

The LCA Terrebonne Basin Barrier Shoreline Restoration Study (LCA TBBSR) was

identified in the Louisiana Coastal Area, (LCA), Louisiana Ecosystem Restoration Study

(USACE 2004; 2004 LCA Plan). The 2004 LCA Plan was recommended to Congress by

a Chief of Engineers report dated January 31, 2005, which called for a coordinated,

feasible solution to the identified critical water resource problems and opportunities in

coastal Louisiana.

The LCA TBBSR, located in LCA Subprovince 3, provides for the restoration of the

Timbalier and Isles Dernieres barrier island chains located in Terrebonne Parish and

Lafourche Parish, Louisiana.

National Ecosystem Restoration (NER) Plan

The NER Plan initial restoration consists of the restoration of Whiskey, Trinity, Raccoon

and Timbalier Islands to their minimal geomorphologic form and ecologic function. This

includes five (5) years of advanced fill for Whiskey and Raccoon Islands and twenty five

(25) years of advanced fill for Raccoon and Timbalier Islands.

The NER Plan will utilize beach/dune material from Ship Shoal blocks 88, 89, 94, and

95; South Pelto blocks 12 and 13. Marsh material will originate from nearshore borrow

areas identified and studied for the Whiskey Island TE-50 marsh creation project

(Whiskey 3A), Raccoon Island TE-48 marsh creation project (Raccoon BA), and New

Cut TE-37 dune/marsh restoration project (New Cut BA). All borrow areas have

published geotechnical and geophysical survey data collected for the previously

mentioned barrier island restoration efforts. Analysis of this data lead to the development

of dredge-to-fill ratios of 1.13:1 for Ship Shoal and South Pelto as beach/dune fill

material; 1.6:1 for Whiskey 3A upper layer as marsh fill material; and 1.3:1 for Raccoon

BA, Whiskey 3A lower layer, and New Cut BA as marsh fill.

Fill quantities for the beach/dune and marsh components initial restorations include:

1) Whiskey Plan C is 8,330,215cy beach/dune from Ship Shoal and 579,724cy

marsh from Whiskey 3A upper layer.

2) Trinity Plan C is 3,813,885cy beach/dune from Ship Shoal and 3,772,925cy for

marsh from Whiskey 3A upper layer.

3) Raccoon Plan E is 5,381,956cy beach/dune from Ship Shoal, 2,763,555cy marsh

from Ship Shoal, and 1,846,154cy marsh from Raccoon BA.

4) Timbalier Plan E are 10,702,818cy beach/dune from South Pelto, 3,083,736cy

marsh from South Pelto, 435,735cy marsh from Whiskey 3A upper layer,

3,630,769cy marsh from Whiskey 3A lower layer, and 1,923,077cy marsh from

New Cut BA.


For the beach/dune area it is anticipated that a 30" cutterhead dredge will be used with

the assistance of booster pumps to transport the material from the borrow areas to the

beach/dune fill templates on each island. The material will then be worked, shaped, and

graded by bulldozers. For the marsh area, the material would be pumped by a 30"

cutterhead dredge with the assistance of a booster pumps. The discharge pipe for marsh

fill will be directed within the marsh fill template through movements of the pipeline with

the assistance of a marsh backhoe. Containment dikes would be constructed around the

perimeter of the marsh fill template to retain the sediment. Sediment for the containment

dikes will be dredged from existing material alongside the dike alignment by a barge

mounted clam shell dredge. Access channel and containment dike costs were developed

from past construction projects as a per linear foot unit cost. This method was chosen

because the survey data available was widely spaced (~1500 feet) preventing the

designers of the feasibility level construction templates from determining definitive cubic

yard excavation volumes. Construction operations would be completed in a manner that

will minimize turbidity of the water at the dredge site and the discharge site.

Sand fencing will be installed in a single row along the entire length of the dune feature

for each island. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-foot centers and follows

recommendations developed for restoration efforts in the area.

Vegetative Plantings will take place in years TY1, TY2, and TY3 following fill

completion. TY1 plantings consist of aerial seeding and planting the dune/swale area

with planting on 8-foot centers. TY2 plantings consist of planting 50% of the marsh fill

area on 8-foot centers and woody species on the dune/swale and marsh areas. TY3

plantings consist of planting the remaining 50% of the marsh fill area.

The NER project costs were subdivided into two contracts for initial restoration and

individual contracts for renourishments or O&M. Contract No. 1 consists of the initial

restoration of Whiskey Island, Trinity Island, and Raccoon Island with terminal groin.

Contract No. 2 consists of initial restoration of Timbalier Island. The individual O&M

and renourishment contracts are Raccoon Island terminal groin O&M (No. 3), Whiskey

Island renourishment in TY20 (No. 4), Trinity Island renourishment in TY25 (No. 5),

Raccoon Island and Timbalier Island renourishment in TY30 (No. 6), and Whiskey Island

renourishment in TY40 (No. 7).

MII Costing Element Descriptions

[01] Lands and Damages

Whiskey, Trinity, and Raccoon Islands are owned in entirety by the State of Louisiana.

Timbalier Island is owned in majority by the State of Louisiana. Cost for Lands and

Damages were obtained from the USACE Real Estate Division.


[06] Fish and Wildlife

This feature code is included to capture the cost associated with the Adaptive

Management and Monitoring Plan (AMP) and is inclusive of cost contingency and

escalation. The cost elements of the AMP include program setup, implementation, and

post construction monitoring. Cost associated with AMP setup coincides with the PED

of the project and includes initial monitoring, database development, and the creation of

the detailed AMP. Implementation costs are associated with administering the AMP

during construction and the post monitoring phase. Post construction monitoring costs

were developed by the development team and are planned to support the monitoring for

10 years post-construction.

[10] Breakwaters and Seawalls

This feature code includes all the elements of construction for the terminal groin in

Raccoon Island.

Mob/Demob: This is for the mobilization and demobilization of all equipment

required for construction of the terminal groin on Raccoon Island. Costs are from

historical contract bids in 2009 dollars.

Survey Crew: This item detail is for the survey crew consisting of a Survey Chief,

Rodman, and boat operator. Equipment includes survey vessel. Survey crew will

operate during daylight hours for 12hrs/day and will conduct pre-construction,

stake out, progress, and post construction surveys. Equipment is assumed to work

50% of one 12 hour shift x 30.4 days/mo = 182.5 hrs/mo. Labor is paid for full 12

hours shift x 30.4 days = 365 hrs/mo.

Quality Control Inspector: This item detail is for the quality control inspector.

Inspector will work during daylight hours for 12hrs/day. Labor is paid for full 12

hours shift x 30.4 days = 365 hrs/mo.

Rip-Rap Rock: 20,950 tons of rock would be required for initial construction of

the terminal groin following beach/dune restoration on Raccoon Island. Costs are

from historical contract bids in 2009 dollars.

Geotextile Fabric: 12,160 square yards of geotextile fabric would be used as an

underlayment of the rock. Costs are from historical contract bids in 2009 dollars.

[17] Beach Replenishment

This feature code includes all the elements of construction on the island. Details of the

individual elements are listed below.

Shore Pre-layout/Pick-up Pipeline: This item is for all equipment, labor and

materials required for the installation, standby, and removal of the shore pipeline.


Submerged Pre-layout/Pick-up Pipeline for Beach/Dune Fill: This item is for all

equipment, labor and materials required for the installation, standby, and removal

of the submerged pipeline for beach / dune fill. It includes submerged pipeline

pre-layout from borrow area to beach for each island for beach/dune fill. USACE

review of prior projects indicates the crews can pre-lay 1,500ft of pipeline per day

while working 12 hours per day. Submerged pipeline pick-up is for the extraction

of the submerged pipeline from the respective borrow area and every subsequent

reorientation of the pipeline for marsh fill construction.

Submerged Pre-layout/Pick-up Pipeline for Marsh Fill: This item is for all

equipment, labor and materials required for the installation, standby, and removal

of the submerged pipeline for marsh fill. It includes submerged pipeline prelayout of submerged pipeline from borrow area to Island. USACE review of prior

projects indicates the crews can pre-lay of 1500' of pipeline per day while

working 12 hours per day. Submerged pipeline pick-up is for the final extraction

of the submerged pipeline from borrow area to island.

Dredge Mob/Demob: includes dredge, boosters, plant tugs/tenders, attendant

plant, pipeline standby cost, transfer of shore pipe and float hose on barge, and

work barges. Costs are from USACE CEDEP program. Because construction

requires multiple contracts and within those contracts multiple relocations of the

dredge, Dredge Mob/Demob is broken down by both contract and relocation. All

costs associated with each separate contract and relocation account for transfer

distances and times unique to each individual case.

Dredge Standby Cost: This item calculates the standby costs for the dredge during

pipeline pre-lay.

Mob/Demob Crew & Equipment: This item is for all equipment, labor, and

materials required for the mobilization/demobilization of the shore equipment &

crews, pipeline handling equipment & crews. A time table developed for this

element is shown below.

Mob/Demob of crews and equipment:

Mob prep time: 1.0 day

Mobilize: 4.2 days

Prep for work: 0.5 days

Demobilize: 2.1 days.

Total time: 7.8 days (7.8 x 12 hrs/day = 94 hrs)

Mob/demob of the Marsh Backhoe(s): Allow 3 days at 10 hours/day (min

rental).

Mob/demob of dredge and pipeline are priced in separate item details.


Mob/Demob Pipeline: This item is for all equipment, labor and materials required

for the mob/demob of the floating and submerged pipeline. Only mob/demob of

the submerged and pontoon line will be paid for in this item detail. Mob/demob of

shore pipeline and float hose is included in the USACE CEDEP program for

dredge mob/demob. The submerged and floating pipeline is being mobilized

while in rafts of 6,000-ft bundles. Each raft will be towed by a 1,200 HP tug and

followed by a tender with a minimum of 300 HP. A time table developed for this

element is shown below.

Breakdown:

Home to Pipeline (Mob)*: 0.5 day (24 hrs/day)

Pipeline to Jobsite (Mob): 4.2 days

Jobsite to Home (Mob)*: 2.1 days

Home to Jobsite (Demob)*: 2.1 days

Jobsite to Pipeline Yard (Demob): 4.2 days

Pipeline Yard to Home (Demob)*: 0.5 day

Total pipeline mob/demob: 13.6 days

*Tug is not towing during these trips so it can travel at twice the speed

and thus reduce the travel time.

CEDEP inputs include:

78,000 linear feet of pipeline to be mobilized

Tugs required for pipeline: 1200 HP tugs = 13, 600HP tug/tender = 1 (min

HP required), 300 HP tender = 12 (min HP required).

Less potential tugs in CEDEP plant mob/demob: 2-900 HP, 2- 600 HP,

xx -300 HP. Tugs Requires: 13 - 1200 HP, 11 - 600 HP rentals (assumes

extra 0-900 HP and 2-600 HP avail from dredge plant).

NER Plan Construction

Construction activities for the NER Plan include the following:

Beach/Dune Fill

Beach/Dune Fill: Unit price for beach/dune fill was developed in USACE

dredging program CEDEP. Quantities used in the MCACES cost estimate

are in place fill from feasibility level island designs on the gulf side of the

existing beach on each island.

Beach/Dune Construction: This item detail is for crew and equipment for

fill placement, grading, and shaping of the beach/dune material.

Equipment includes two dozers with operators and a foreman for

24hrs/day. Foreman will oversee all fill area operations for beach and fill

including the shore pipeline crew. This crew is priced on a monthly basis

and includes the 2 dozers (1 D-5 LGP and 1 D-7 LGP equivalent). The


crews and equipment are assumed to work 2 - 12 hour shifts or 730 hours

per month.

Survey Crew - Offshore: This item detail is for the offshore survey crew

consisting of a Survey Chief, Rodman, and boat operator and includes a

survey vessel for equipment. The offshore survey crews will operate

during daylight hours for 12hrs/day and will conduct borrow area, access

channel and gulf beach face surveys during construction. The survey

vessel is assumed to work 50% of one 12 hour shift or 182.5 hrs/mo.

Survey crew labor is paid for full 12 hours shift or 365 hrs/mo.

Survey Crew - Onshore: This item detail is for the onshore fill area survey

crew consisting of a Survey Chief and two Rodmen. Onshore survey crew

will work 12hrs/day, 7 days a week and conduct surveys of fill template

areas. Equivalent crew work hours equal 365hrs/mo.

Pipeline Crew - Offshore: This item detail is for the equipment and crew

maintaining the submerged sections of the sediment pipeline during

construction. This crew and equipment are priced on a monthly basis. The

equipment is assumed to work 50% of one 12 hour shift or 182.5 hrs/mo.

Crew labor is paid for full 12 hours shift or 365 hrs/mo.

Pipeline Crew - Onshore: This item detail is for the equipment and crew

maintaining the submerged sections of the sediment pipeline during

construction. This crew and equipment are priced on a monthly basis. The

equipment is assumed to work 50% of one 12 hour shift or 182.5 hrs/mo.

Crew labor is paid for full 12 hours shift or 365 hrs/mo.

Marsh Fill (initial restoration only)

Marsh Fill: Unit price for marsh fill developed in USACE dredging

program CEDEP. Marsh fill quantities are in place fill from feasibility

level island designs.

Marsh Construction: This item detail is for the equipment and crew for

marsh fill placement. Equipment includes a marsh backhoe with operator

operating for 12hrs/day. A laborer and general foreman are paid for 2 -

12hr shifts. Foreman will oversee all fill area operations for the marsh fill

including the shore pipeline crew. This crew is priced on a monthly basis.

The equipment includes one (1) marsh backhoe that is assumed to work

one 12 hour shift per day or 365 hrs/mo. Crew labor is paid full time with

the marsh backhoe operator being paid with marsh backhoe rental.

Marsh Grade Stakes: Material cost includes grade stakes at an estimated

$350.00/stake. Stakes are to be spaced along each survey line (250ft

spacing) at an interval of 150ft. Quantity of grade stakes are estimated at


1.16 per acre. Marsh acres are calculated based upon feasibility level

island designs.

Access Channel

The Access Channel linear foot cost was derived from recent constructed

project bids. Channel length is estimated from feasibility level island

designs as the length of the northern marsh containment dike (CDN). The

final access channel design lengths can not be determined until a more

detailed survey of the area is conducted for final design. The Access

channel is to remain un-filled after construction for vegetative plantings

access and maintenance operations of the containment dikes if required.

Access channel for renourishments was estimated at 5000 feet, average

distance from deep water to beach/dune fill area.

Containment Dike

The containment dike linear foot cost was derived from recently

constructed project bids. The length of containment dikes is a summation

of feasibility level island design lengths of the northern marsh containment

dike (CDN) and beach/dune - marsh separation dike (CDS). Containment

dikes will be constructed of in-situ material with no weirs, armoring, or

structural bracing. Plantings of vegetative cover for dikes are included in

plantings of dune/swale and marsh fill areas. The CDN is the only dike

included in renourishment events.

Sand Fencing

Sand fencing length derived from feasibility level island design length of

the dune feature. Cost was derived from historic construction bids. The

sand fencing would require transport to the fill site by small marine vessel.

Unit prices include transport, materials, installation, equipment, and crews

Fencing Materials: Fencing shall be standard, weather resistant snow

fencing. Slats shall be made of No. 1 aspen or spruce measuring 3/8 inch

thick, 1-1/2 inch wide by 4 feet long. The distance between the slats shall

be 3 inches on center (50% porosity). The slats shall be painted with a

high quality red oxide stain. Post shall be 4 inch by 4 inch untreated #2

grade lumber 10 feet long driven 6 feet into the ground. They shall be

placed on 10 feet centers.

Vegetative Plantings

Vegetative planting species and planting schemes are consistent with

Louisiana past and planned restoration projects. Unit costs were developed

from an average of past restoration projects along the Louisiana Gulf

Coast. One such from a winning bid for Pass Chaland (BA-35) in 2008,

one from the average of submitted construction bids for East Grande Terre

(BA-30) in 2009, and one from feasibility design cost estimates from Shell

Island. All were escalated to 2009 price levels before computing unit


price. Plantings will be scheduled for the season of the year that promotes

the greatest survivability. No re-plantings for die-offs are considered for

this project.

Plantings in the first year following construction include plantings in the

following areas and described species:

Aerial Seeding: Aerial Seeding will be done over the dune/swale

habitat area if required by the construction completion season for

protection of newly created fill areas.

Dune/Swale Area: Dune and Swale habitat shall be planted with a

combination of Bitter Pancium, Marshhay Grass, Sea Oats, and

Gulf Cordgrass. Planting scheme is 8 ft on center of one of the

above plants over 100% of the dune/swale area. There are 681

plants per acre with this planting scheme.

Plantings in second year following construction include plantings in the

following areas and described species:

Woody Species: Woody species shall be planted over 15% of the

dune/swale and marsh areas. There are 102 plants per acre with

this planting scheme.

Marsh Area (initial restoration only): Marsh area shall be planted

with Smooth Cordgrass at 8 ft centers over 100% of the marsh area

(50% in TY2 and 50% in TY3). There are 681 plants per acre with

this planting scheme.

Plantings in third year following construction include plantings in the

following areas and described species:

Marsh Area (initial restoration only): Marsh area shall be planted

with Smooth Cordgrass at 8 ft centers over 100% of the marsh area

(50% in TY2 and 50% in TY3). There are 681 plants per acre with

this planting scheme.

[30] Planning, Engineering & Design

PED was assessed at 5.0% of construction cost. Percentage derived from USACE New

Orleans District from graded scale based on project cost.

[31] Construction Management

Construction Management was assessed at 5.0% of construction cost. Percentage derived

from USACE New Orleans District from graded scale based on project cost.


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 2

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1.4.1.1.1 02A-1 Whiskey Island Plan C 1.00 EA 3,865,627.92 3,865,627.92

24,540.32 24,540.32

1.4.1.1.1.1 USR 02A-1-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

3,674,213.41 3,674,213.41

1.4.1.1.1.1 02A-1-1 Pre-layout/Pick-up Pipeline 1.00 EA 3,674,213.41 3,674,213.41

511,957.13 511,957.13

1.4.1.1.1.1.1 02A-1-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 511,957.13 511,957.13

29.47 29.47

1.4.1.1.1.1.1.1 USR Pre-lay Shore Pipeline 5,656.00 LF 166,658.99 166,658.99

29.47 29.47

1.4.1.1.1.1.1.2 USR Pickup Shore Pipeline 11,071.00 LF 326,216.70 326,216.70

349.15 349.15

1.4.1.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 11.31 DAY 3,949.55 3,949.55

683.40 683.40

1.4.1.1.1.1.1.4 USR Pickup 30-inch Shore Pipeline Standby Cost 22.14 DAY 15,131.89 15,131.89

50.27 50.27

1.4.1.1.1.1.2 02A-1-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 3,162,256.28 3,162,256.28

2,071,163.92 2,071,163.92

1.4.1.1.1.1.2.1 02A-1-1-2-1 Beach/Dune 1.00 EA 2,071,163.92 2,071,163.92

7.58 7.58

1.4.1.1.1.1.2.1.1 USR Pre-lay Submerged Pipeline 62,908.00 LF 476,931.96 476,931.96

7.61 7.61

1.4.1.1.1.1.2.1.2 USR Pickup Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

9,708.27 9,708.27

1.4.1.1.1.1.2.1.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

9,708.27 9,708.27

1.4.1.1.1.1.2.1.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

7,180.12 7,180.12

1.4.1.1.1.1.2.1.5 USR Pickup Dredge Standby Cost 41.94 DAY 301,124.60 301,124.60

31.82 31.82

1.4.1.1.1.1.2.2 02A-1-1-2-2 Marsh 34,288.00 LF 1,091,092.36 1,091,092.36

7.58 7.58

1.4.1.1.1.1.2.2.1 USR Pre-lay Submerged Pipeline 34,288.00 LF 259,951.73 259,951.73

7.61 7.61

1.4.1.1.1.1.2.2.2 USR Pickup Submerged Pipeline 34,288.00 LF 260,971.91 260,971.91

5,291.49 5,291.49

1.4.1.1.1.1.2.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 22.86 DAY 120,956.43 120,956.43

5,291.49 5,291.49

1.4.1.1.1.1.2.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 22.86 DAY 120,956.43 120,956.43


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 3

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

7,180.12 7,180.12

1.4.1.1.1.1.2.2.5 USR Pre-lay Dredge Standby Cost 22.86 DAY 164,127.94 164,127.94

7,180.12 7,180.12

1.4.1.1.1.1.2.2.6 USR Pickup Dredge Standby Cost 22.86 DAY 164,127.94 164,127.94

4,975,923.98 4,975,923.98

1.4.1.1.2 02A-2 Trinity Island Plan C 1.00 EA 4,975,923.98 4,975,923.98

24,540.32 24,540.32

1.4.1.1.2.1 USR 02A-2-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

4,784,509.47 4,784,509.47

1.4.1.1.2.1 02A-2-1 Pre-layout/Pick-up Pipeline 1.00 EA 4,784,509.47 4,784,509.47

1,196,251.99 1,196,251.99

1.4.1.1.2.1.1 02A-2-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 1,196,251.99 1,196,251.99

29.47 29.47

1.4.1.1.2.1.1.1 USR Pre-lay Shore Pipeline 13,088.00 LF 385,649.37 385,649.37

29.47 29.47

1.4.1.1.2.1.1.2 USR Pickup Shore Pipeline 24,315.00 LF 716,462.75 716,462.75

807.92 807.92

1.4.1.1.2.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 26.18 DAY 21,148.02 21,148.02

1,500.96 1,500.96

1.4.1.1.2.1.1.4 USR Pickup 30-inch Shore Pipeline Standby Cost 48.63 DAY 72,991.86 72,991.86

57.04 57.04

1.4.1.1.2.1.2 02A-2-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 3,588,257.47 3,588,257.47

3,142,801.28 3,142,801.28

1.4.1.1.2.1.2.1 02A-2-1-2-1 Beach/Dune 1.00 EA 3,142,801.28 3,142,801.28

7.58 7.58

1.4.1.1.2.1.2.1.1 USR Pre-lay Submerged Pipeline 77,280.00 LF 585,892.13 585,892.13

7.61 7.61

1.4.1.1.2.1.2.1.2 USR Pickup Submerged Pipeline 77,280.00 LF 588,191.47 588,191.47

11,926.23 11,926.23

1.4.1.1.2.1.2.1.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 51.52 DAY 614,439.13 614,439.13

11,926.23 11,926.23

1.4.1.1.2.1.2.1.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 51.52 DAY 614,439.13 614,439.13

7,180.12 7,180.12

1.4.1.1.2.1.2.1.5 USR Pre-lay Dredge Standby Cost 51.52 DAY 369,919.71 369,919.71

7,180.12 7,180.12

1.4.1.1.2.1.2.1.6 USR Pickup Dredge Standby Cost 51.52 DAY 369,919.71 369,919.71

12.99 12.99

1.4.1.1.2.1.2.2 02A-2-1-2-2 Marsh 34,288.00 LF 445,456.19 445,456.19

7.58 7.58


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 4

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1.4.1.1.2.1.2.2.1 USR Pre-lay Submerged Pipeline 15,889.00 LF 120,461.18 120,461.18

7.61 7.61

1.4.1.1.2.1.2.2.2 USR Pickup Submerged Pipeline 15,889.00 LF 120,933.93 120,933.93

2,452.07 2,452.07

1.4.1.1.2.1.2.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 10.59 DAY 25,973.94 25,973.94

2,452.07 2,452.07

1.4.1.1.2.1.2.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 10.59 DAY 25,973.94 25,973.94

7,180.12 7,180.12

1.4.1.1.2.1.2.2.5 USR Pre-lay Dredge Standby Cost 10.59 DAY 76,056.60 76,056.60

7,180.12 7,180.12

1.4.1.1.2.1.2.2.6 USR Pickup Dredge Standby Cost 10.59 DAY 76,056.60 76,056.60

3,671,109.38 3,671,109.38

1.4.1.1.3 02A-3 Raccoon Island Plan E 1.00 EA 3,671,109.38 3,671,109.38

24,540.32 24,540.32

1.4.1.1.3.1 USR 02A-3-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

3,479,694.87 3,479,694.87

1.4.1.1.3.1 02A-3-1 Pre-layout/Pick-up Pipeline 1.00 EA 3,479,694.87 3,479,694.87

738,886.42 738,886.42

1.4.1.1.3.1.1 02A-3-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 738,886.42 738,886.42

29.47 29.47

1.4.1.1.3.1.1.1 USR Pre-lay Shore Pipeline 10,183.00 LF 300,051.00 300,051.00

29.47 29.47

1.4.1.1.3.1.1.2 USR Pickup Shore Pipeline 13,675.00 LF 402,945.84 402,945.84

628.59 628.59

1.4.1.1.3.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 20.37 DAY 12,801.88 12,801.88

844.16 844.16

1.4.1.1.3.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 27.35 DAY 23,087.69 23,087.69

43.57 43.57

1.4.1.1.3.1.2 02A-3-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 2,740,808.45 2,740,808.45

2,066,763.80 2,066,763.80

1.4.1.1.3.1.2.1 02A-3-1-2-1 Beach/Dune 1.00 EA 2,066,763.80 2,066,763.80

7.58 7.58

1.4.1.1.3.1.2.1.1 USR Pre-lay Submerged Pipeline 56,721.00 LF 430,025.72 430,025.72

7.61 7.61

1.4.1.1.3.1.2.1.2 USR Pickup Submerged Pipeline 56,721.00 LF 431,713.36 431,713.36

8,753.46 8,753.46

1.4.1.1.3.1.2.1.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 37.81 DAY 331,003.36 331,003.36

8,753.46 8,753.46

1.4.1.1.3.1.2.1.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 37.81 DAY 331,003.36 331,003.36


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 5

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

7,180.12 7,180.12

1.4.1.1.3.1.2.1.5 USR Pre-lay Dredge Standby Cost 37.81 DAY 271,509.00 271,509.00

7,180.12 7,180.12

1.4.1.1.3.1.2.1.6 USR Pickup Dredge Standby Cost 37.81 DAY 271,509.00 271,509.00

19.66 19.66

1.4.1.1.3.1.2.2 02A-3-1-2-2 Marsh 34,288.00 LF 674,044.65 674,044.65

7.58 7.58

1.4.1.1.3.1.2.2.1 USR Pre-lay Submerged Pipeline 26,503.00 LF 200,930.37 200,930.37

7.61 7.61

1.4.1.1.3.1.2.2.2 USR Pickup Submerged Pipeline 26,503.00 LF 201,718.92 201,718.92

4,090.07 4,090.07

1.4.1.1.3.1.2.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 17.67 DAY 72,266.12 72,266.12

4,090.07 4,090.07

1.4.1.1.3.1.2.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 17.67 DAY 72,266.12 72,266.12

7,180.12 7,180.12

1.4.1.1.3.1.2.2.5 USR Pre-lay Dredge Standby Cost 17.67 DAY 126,863.12 126,863.12

70,204,825.20 70,204,825.20

1.4.1.2 02B Whiskey Island Plan C 1.00 EA 70,204,825.20 70,204,825.20

63,284,139.31 63,284,139.31

1.4.1.2.1 02B-1 Beach/Dune Fill 1.00 EA 63,284,139.31 63,284,139.31

6.97 6.97

1.4.1.2.1.1 USR Beach/Dune Fill 8,330,215.00 CY 58,064,427.87 58,064,427.87

223,915.42 223,915.42

1.4.1.2.1.2 USR Beach/Dune Construction 10.69 MO 2,393,655.86 2,393,655.86

50,526.76 50,526.76

1.4.1.2.1.3 USR Survey Crew - Offshore 10.69 MO 540,131.10 540,131.10

29,937.08 29,937.08

1.4.1.2.1.4 USR Survey Crew - Onshore 10.69 MO 320,027.34 320,027.34

116,880.03 116,880.03

1.4.1.2.1.5 USR Pipeline Crew - Offshore 10.69 MO 1,249,447.51 1,249,447.51

67,020.55 67,020.55

1.4.1.2.1.6 USR Pipeline Crew - Shore 10.69 MO 716,449.64 716,449.64

3,306,633.64 3,306,633.64

1.4.1.2.2 02B-2 Marsh Fill 1.00 EA 3,306,633.64 3,306,633.64

5.05 5.05

1.4.1.2.2.1 USR Marsh Fill 579,724.00 CY 2,930,005.83 2,930,005.83

149,212.56 149,212.56

1.4.1.2.2.2 USR Marsh Construction 0.76 MO 113,401.54 113,401.54

490.62 490.62


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 6

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1.4.1.2.2.3 USR Marsh Grade Stakes 127.00 EA 62,309.31 62,309.31

50,526.76 50,526.76

1.4.1.2.2.4 USR Survey Crew - Offshore 0.76 MO 38,400.34 38,400.34

29,937.08 29,937.08

1.4.1.2.2.5 USR Survey Crew - Onshore 0.76 MO 22,752.18 22,752.18

116,880.03 116,880.03

1.4.1.2.2.6 USR Pipeline Crew - Offshore 0.76 MO 88,828.82 88,828.82

67,020.55 67,020.55

1.4.1.2.2.7 USR Pipeline Crew - Shore 0.76 MO 50,935.62 50,935.62

626,450.00 626,450.00

1.4.1.2.3 02B-3 Access Channel 1.00 EA 626,450.00 626,450.00

85.00 85.00

1.4.1.2.3.1 USR Access Channel 7,370.00 LF 626,450.00 626,450.00

1,327,620.00 1,327,620.00

1.4.1.2.4 02B-4 Containment Dike 1.00 EA 1,327,620.00 1,327,620.00

52.50 52.50

1.4.1.2.4.1 USR Containment Dike 25,288.00 LF 1,327,620.00 1,327,620.00

293,718.75 293,718.75

1.4.1.2.5 02B-5 Sand Fencing 1.00 EA 293,718.75 293,718.75

16.25 16.25

1.4.1.2.5.1 USR Sand Fencing 18,075.00 LF 293,718.75 293,718.75

1,366,263.50 1,366,263.50

1.4.1.2.6 02B-6 Vegetative Plantings 1.00 EA 1,366,263.50 1,366,263.50

779,938.00 779,938.00

1.4.1.2.6.1 02B-6-1 Plantings - TY1 1.00 EA 779,938.00 779,938.00

1.4.1.2.6.1.1 USR Planting Mob/Demob - TY1 1.00 LS 20,000.00 20,000.00

100.00 100.00

1.4.1.2.6.1.2 USR Aerial Seeding - TY1 122.00 ACR 12,200.00 12,200.00

9.00 9.00

1.4.1.2.6.1.3 USR Dune/Swale Area - TY1 83,082.00 EA 747,738.00 747,738.00

399,650.75 399,650.75

1.4.1.2.6.2 02B-6-2 Plantings - TY2 1.00 EA 399,650.75 399,650.75

1.4.1.2.6.2.1 USR Planting Mob/Demob - TY2 1.00 LS 20,000.00 20,000.00

9.00 9.00

1.4.1.2.6.2.2 USR Woody Species - TY2 23,664.00 EA 212,976.00 212,976.00

4.45 4.45

1.4.1.2.6.2.3 USR Marsh Area - TY2 37,455.00 EA 166,674.75 166,674.75

186,674.75 186,674.75

1.4.1.2.6.3 02B-6-3 Plantings - TY3 1.00 EA 186,674.75 186,674.75

1.4.1.2.6.3.1 USR Planting Mob/Demob - TY3 1.00 LS 20,000.00 20,000.00


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 7

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

4.45 4.45

1.4.1.2.6.3.2 USR Marsh Area - TY3 37,455.00 EA 166,674.75 166,674.75

71,170,477.78 71,170,477.78

1.4.1.3 02C Trinity Island Plan C 1.00 EA 71,170,477.78 71,170,477.78

36,538,498.30 36,538,498.30

1.4.1.3.1 02C-1 Beach/Dune Fill 1.00 EA 36,538,498.30 36,538,498.30

8.87 8.87

1.4.1.3.1.1 USR Beach/Dune Fill 3,813,885.00 CY 33,843,193.61 33,843,193.61

223,915.42 223,915.42

1.4.1.3.1.2 USR Beach/Dune Construction 5.52 MO 1,236,013.13 1,236,013.13

50,526.76 50,526.76

1.4.1.3.1.3 USR Survey Crew - Offshore 5.52 MO 278,907.73 278,907.73

29,937.08 29,937.08

1.4.1.3.1.4 USR Survey Crew - Onshore 5.52 MO 165,252.66 165,252.66

116,880.03 116,880.03

1.4.1.3.1.5 USR Pipeline Crew - Offshore 5.52 MO 645,177.76 645,177.76

67,020.55 67,020.55

1.4.1.3.1.6 USR Pipeline Crew - Shore 5.52 MO 369,953.41 369,953.41

26,321,629.03 26,321,629.03

1.4.1.3.2 02C-2 Marsh Fill 1.00 EA 26,321,629.03 26,321,629.03

6.21 6.21

1.4.1.3.2.1 USR Marsh Fill 3,772,925.00 CY 23,435,809.38 23,435,809.38

149,212.56 149,212.56

1.4.1.3.2.2 USR Marsh Construction 6.26 MO 934,070.62 934,070.62

490.62 490.62

1.4.1.3.2.3 USR Marsh Grade Stakes 605.00 EA 296,827.80 296,827.80

50,526.76 50,526.76

1.4.1.3.2.4 USR Survey Crew - Offshore 6.26 MO 316,297.54 316,297.54

29,937.08 29,937.08

1.4.1.3.2.5 USR Survey Crew - Onshore 6.26 MO 187,406.09 187,406.09

116,880.03 116,880.03

1.4.1.3.2.6 USR Pipeline Crew - Offshore 6.26 MO 731,668.98 731,668.98

67,020.55 67,020.55

1.4.1.3.2.7 USR Pipeline Crew - Shore 6.26 MO 419,548.62 419,548.62

1,975,145.00 1,975,145.00

1.4.1.3.3 02C-3 Access Channel 1.00 EA 1,975,145.00 1,975,145.00

85.00 85.00

1.4.1.3.3.1 USR Access Channel 23,237.00 LF 1,975,145.00 1,975,145.00

2,395,522.50 2,395,522.50


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 8

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1.4.1.3.4 02C-4 Containment Dike 1.00 EA 2,395,522.50 2,395,522.50

52.50 52.50

1.4.1.3.4.1 USR Containment Dike 45,629.00 LF 2,395,522.50 2,395,522.50

364,552.50 364,552.50

1.4.1.3.5 02C-5 Sand Fencing 1.00 EA 364,552.50 364,552.50

16.25 16.25

1.4.1.3.5.1 USR Sand Fencing 22,434.00 LF 364,552.50 364,552.50

3,575,130.45 3,575,130.45

1.4.1.3.6 02C-6 Vegetative Plantings 1.00 EA 3,575,130.45 3,575,130.45

1,290,716.00 1,290,716.00

1.4.1.3.6.1 02C-6-1 Plantings - TY1 1.00 EA 1,290,716.00 1,290,716.00

1.4.1.3.6.1.1 USR Planting Mob/Demob - TY1 1.00 LS 20,000.00 20,000.00

100.00 100.00

1.4.1.3.6.1.2 USR Aerial Seeding - TY1 204.00 ACR 20,400.00 20,400.00

9.00 9.00

1.4.1.3.6.1.3 USR Dune/Swale Area - TY1 138,924.00 EA 1,250,316.00 1,250,316.00

1,474,984.45 1,474,984.45

1.4.1.3.6.2 02C-6-2 Plantings - TY2 1.00 EA 1,474,984.45 1,474,984.45

1.4.1.3.6.2.1 USR Planting Mob/Demob - TY2 1.00 LS 20,000.00 20,000.00

9.00 9.00

1.4.1.3.6.2.2 USR Woody Species - TY2 73,950.00 EA 665,550.00 665,550.00

4.45 4.45

1.4.1.3.6.2.3 USR Marsh Area - TY2 177,401.00 EA 789,434.45 789,434.45

809,430.00 809,430.00

1.4.1.3.6.3 02C-6-3 Plantings - TY3 1.00 EA 809,430.00 809,430.00

1.4.1.3.6.3.1 USR Planting Mob/Demob - TY3 1.00 LS 20,000.00 20,000.00

4.45 4.45

1.4.1.3.6.3.2 USR Marsh Area - TY3 177,400.00 EA 789,430.00 789,430.00

71,950,203.06 71,950,203.06

1.4.1.4 02D Raccoon Island Plan E 1.00 EA 71,950,203.06 71,950,203.06

39,549,447.34 39,549,447.34

1.4.1.4.1 02D-1 Beach/Dune Fill 1.00 EA 39,549,447.34 39,549,447.34

6.74 6.74

1.4.1.4.1.1 USR Beach/Dune Fill 5,381,956.00 CY 36,268,206.84 36,268,206.84

223,915.42 223,915.42

1.4.1.4.1.2 USR Beach/Dune Construction 6.72 MO 1,504,711.63 1,504,711.63

50,526.76 50,526.76

1.4.1.4.1.3 USR Survey Crew - Offshore 6.72 MO 339,539.85 339,539.85

29,937.08 29,937.08

1.4.1.4.1.4 USR Survey Crew - Onshore 6.72 MO 201,177.15 201,177.15


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 9

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

116,880.03 116,880.03

1.4.1.4.1.5 USR Pipeline Crew - Offshore 6.72 MO 785,433.79 785,433.79

67,020.55 67,020.55

1.4.1.4.1.6 USR Pipeline Crew - Shore 6.72 MO 450,378.07 450,378.07

27,521,103.12 27,521,103.12

1.4.1.4.2 02D-2 Marsh Fill 1.00 EA 27,521,103.12 27,521,103.12

3.16 3.16

1.4.1.4.2.1 USR Marsh Fill - Raccoon BA 1,846,154.00 CY 5,840,602.99 5,840,602.99

7.01 7.01

1.4.1.4.2.2 USR Marsh Fill - Ship Shoal 2,763,555.00 CY 19,369,538.29 19,369,538.29

149,212.56 149,212.56

1.4.1.4.2.3 USR Marsh Construction 5.15 MO 768,444.68 768,444.68

490.62 490.62

1.4.1.4.2.4 USR Marsh Grade Stakes 369.00 EA 181,040.43 181,040.43

50,526.76 50,526.76

1.4.1.4.2.5 USR Survey Crew - Offshore 5.15 MO 260,212.83 260,212.83

29,937.08 29,937.08

1.4.1.4.2.6 USR Survey Crew - Onshore 5.15 MO 154,175.94 154,175.94

116,880.03 116,880.03

1.4.1.4.2.7 USR Pipeline Crew - Offshore 5.15 MO 601,932.15 601,932.15

67,020.55 67,020.55

1.4.1.4.2.8 USR Pipeline Crew - Shore 5.15 MO 345,155.81 345,155.81

1,062,925.00 1,062,925.00

1.4.1.4.3 02D-3 Access Channel 1.00 EA 1,062,925.00 1,062,925.00

85.00 85.00

1.4.1.4.3.1 USR Access Channel 12,505.00 LF 1,062,925.00 1,062,925.00

1,738,485.00 1,738,485.00

1.4.1.4.4 02D-4 Containment Dike 1.00 EA 1,738,485.00 1,738,485.00

52.50 52.50

1.4.1.4.4.1 USR Containment Dike 33,114.00 LF 1,738,485.00 1,738,485.00

198,022.50 198,022.50

1.4.1.4.5 02D-5 Sand Fencing 1.00 EA 198,022.50 198,022.50

16.25 16.25

1.4.1.4.5.1 USR Sand Fencing 12,186.00 LF 198,022.50 198,022.50

1,880,220.10 1,880,220.10

1.4.1.4.6 02D-6 Vegetative Plantings 1.00 EA 1,880,220.10 1,880,220.10

512,091.00 512,091.00

1.4.1.4.6.1 02D-6-1 Plantings - TY1 1.00 EA 512,091.00 512,091.00

1.4.1.4.6.1.1 USR Planting Mob/Demob - TY1 1.00 LS 20,000.00 20,000.00


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 10

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

100.00 100.00

1.4.1.4.6.1.2 USR Aerial Seeding - TY1 79.00 ACR 7,900.00 7,900.00

9.00 9.00

1.4.1.4.6.1.3 USR Dune/Swale Area - TY1 53,799.00 EA 484,191.00 484,191.00

866,287.55 866,287.55

1.4.1.4.6.2 02D-6-2 Plantings - TY2 1.00 EA 866,287.55 866,287.55

1.4.1.4.6.2.1 USR Planting Mob/Demob - TY2 1.00 LS 20,000.00 20,000.00

9.00 9.00

1.4.1.4.6.2.2 USR Woody Species - TY2 40,494.00 EA 364,446.00 364,446.00

4.45 4.45

1.4.1.4.6.2.3 USR Marsh Area - TY2 108,279.00 EA 481,841.55 481,841.55

501,841.55 501,841.55

1.4.1.4.6.3 02D-6-3 Plantings - TY3 1.00 EA 501,841.55 501,841.55

1.4.1.4.6.3.1 USR Planting Mob/Demob - TY3 1.00 LS 20,000.00 20,000.00

4.45 4.45

1.4.1.4.6.3.2 USR Marsh Area - TY3 108,279.00 EA 481,841.55 481,841.55

11,553,007.17 11,553,007.17

1.5 30 Planning, Engineering & Design 1.00 EA 11,553,007.17 11,553,007.17

1.5.1 USR PED 1.00 LS 11,553,007.17 11,553,007.17

11,553,007.17 11,553,007.17

1.6 31 Construction Management 1.00 EA 11,553,007.17 11,553,007.17

1.6.1 USR Construction Management 1.00 LS 11,553,007.17 11,553,007.17

245,062,709.83 245,062,709.83

2 Contract #2 - Initial Restoration - Timbalier Island 1.00 EA 245,062,709.83 245,062,709.83

382,308.00 382,308.00

2.1 01 Lands & Damages 1.00 EA 382,308.00 382,308.00

2.1.1 USR 01A Acquisitions / Interagency Donations 1.00 LS 382,308.00 382,308.00

222,436,728.93 222,436,728.93

2.2 17 Beach Replenishment 1.00 EA 222,436,728.93 222,436,728.93

222,436,728.93 222,436,728.93

2.2.1 02 Beach and Marsh Construction 1.00 EA 222,436,728.93 222,436,728.93

12,256,189.00 12,256,189.00

2.2.1.1 02A Mobilization / Demobilization 1.00 EA 12,256,189.00 12,256,189.00

151,176.64 151,176.64

2.2.1.1.1 USR 02A-2 Mob/Demob Pipeline - Contract #2 13.60 DAY 2,056,002.25 2,056,002.252.2.1.1.2 USR 02A-3 Dredge Mob - Job Contract #2 1.00 LS 716,455.75 716,455.752.2.1.1.3 USR 02A-4 Dredge Demob/Mob BA Relocation #1 Contract #2 1.00 LS 135,713.28 135,713.282.2.1.1.4 USR 02A-5 Dredge Demob/Mob BA Relocation #2 & Final Demob Contract #2 1.00 LS 341,978.75 341,978.75

9,006,038.97 9,006,038.97

2.2.1.1.1 02A-1 Timbalier Island Plan E 1.00 EA 9,006,038.97 9,006,038.97

24,540.32 24,540.32


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 11

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

2.2.1.1.1.1 USR 02A-1-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

8,814,624.45 8,814,624.45

2.2.1.1.1.1 02A-1-1 Pre-layout/Pick-up Pipeline 1.00 EA 8,814,624.45 8,814,624.45

1,069,408.36 1,069,408.36

2.2.1.1.1.1.1 02A-1-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 1,069,408.36 1,069,408.36

29.47 29.47

2.2.1.1.1.1.1.1 USR Pre-lay Shore Pipeline 12,068.00 LF 355,594.18 355,594.18

29.47 29.47

2.2.1.1.1.1.1.2 USR Pickup Shore Pipeline 21,925.00 LF 646,039.30 646,039.30

349.15 349.15

2.2.1.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 24.14 DAY 8,427.02 8,427.02

1,353.43 1,353.43

2.2.1.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 43.85 DAY 59,347.86 59,347.86

123.12 123.12

2.2.1.1.1.1.2 02A-1-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 7,745,216.09 7,745,216.09

3,196,237.07 3,196,237.07

2.2.1.1.1.1.2.1 02A-1-1-2-1 Beach/Dune 1.00 EA 3,196,237.07 3,196,237.07

7.58 7.58

2.2.1.1.1.1.2.1.1 USR Pre-lay Submerged Pipeline 85,206.00 LF 645,982.47 645,982.47

7.61 7.61

2.2.1.1.1.1.2.1.2 USR Pickup Submerged Pipeline 85,206.00 LF 648,517.63 648,517.63

13,149.40 13,149.40

2.2.1.1.1.1.2.1.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 56.80 DAY 746,938.76 746,938.76

13,149.40 13,149.40

2.2.1.1.1.1.2.1.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 56.80 DAY 746,938.76 746,938.76

7,180.12 7,180.12

2.2.1.1.1.1.2.1.5 USR Pickup Dredge Standby Cost 56.80 DAY 407,859.46 407,859.46

100.94 100.94

2.2.1.1.1.1.2.2 02A-1-1-2-2 Marsh #1 34,288.00 LF 3,461,098.53 3,461,098.53

7.58 7.58

2.2.1.1.1.1.2.2.1 USR Pre-lay Submerged Pipeline 82,796.00 LF 627,711.24 627,711.24

7.61 7.61

2.2.1.1.1.1.2.2.2 USR Pickup Submerged Pipeline 82,796.00 LF 630,174.70 630,174.70

12,777.48 12,777.48

2.2.1.1.1.1.2.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 55.20 DAY 705,282.90 705,282.90

12,777.48 12,777.48

2.2.1.1.1.1.2.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 55.20 DAY 705,282.90 705,282.90

7,180.12 7,180.12

2.2.1.1.1.1.2.2.5 USR Pre-lay Dredge Standby Cost 55.20 DAY 396,323.40 396,323.40


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 12

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

7,180.12 7,180.12

2.2.1.1.1.1.2.2.6 USR Pickup Dredge Standby Cost 55.20 DAY 396,323.40 396,323.40

31.73 31.73

2.2.1.1.1.1.2.3 02A-1-1-2-3 Marsh #2 34,288.00 LF 1,087,880.49 1,087,880.49

7.58 7.58

2.2.1.1.1.1.2.3.1 USR Pre-lay Submerged Pipeline 38,881.00 LF 294,773.19 294,773.19

7.61 7.61

2.2.1.1.1.1.2.3.2 USR Pickup Submerged Pipeline 38,881.00 LF 295,930.03 295,930.03

6,000.30 6,000.30

2.2.1.1.1.1.2.3.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 25.92 DAY 155,531.91 155,531.91

6,000.30 6,000.30

2.2.1.1.1.1.2.3.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 25.92 DAY 155,531.91 155,531.91

7,180.12 7,180.12

2.2.1.1.1.1.2.3.5 USR Pre-lay Dredge Standby Cost 25.92 DAY 186,113.46 186,113.46

210,180,539.94 210,180,539.94

2.2.1.2 02B Timbalier Island Plan E 1.00 EA 210,180,539.94 210,180,539.94

104,104,611.77 104,104,611.77

2.2.1.2.1 02B-1 Beach/Dune Fill 1.00 EA 104,104,611.77 104,104,611.77

9.02 9.02

2.2.1.2.1.1 USR Beach/Dune Fill 10,702,818.00 CY 96,487,446.33 96,487,446.33

223,915.42 223,915.42

2.2.1.2.1.2 USR Beach/Dune Construction 15.60 MO 3,493,080.58 3,493,080.58

50,526.76 50,526.76

2.2.1.2.1.3 USR Survey Crew - Offshore 15.60 MO 788,217.50 788,217.50

29,937.08 29,937.08

2.2.1.2.1.4 USR Survey Crew - Onshore 15.60 MO 467,018.38 467,018.38

116,880.03 116,880.03

2.2.1.2.1.5 USR Pipeline Crew - Offshore 15.60 MO 1,823,328.45 1,823,328.45

67,020.55 67,020.55

2.2.1.2.1.6 USR Pipeline Crew - Shore 15.60 MO 1,045,520.52 1,045,520.52

91,485,733.07 91,485,733.07

2.2.1.2.2 02B-2 Marsh Fill 1.00 EA 91,485,733.07 91,485,733.07

9.08 9.08

2.2.1.2.2.1 USR Marsh Fill - South Pelto 3,083,736.00 CY 27,998,614.82 27,998,614.82

9.89 9.89

2.2.1.2.2.2 USR Marsh Fill - Whiskey 3A Upper 435,735.00 CY 4,309,267.36 4,309,267.36

11.96 11.96

2.2.1.2.2.3 USR Marsh Fill - Whiskey 3A Lower 3,630,769.00 CY 43,424,639.46 43,424,639.46

4.80 4.80


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 13

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

2.2.1.2.2.4 USR Marsh Fill - New Cut 1,923,077.00 CY 9,224,867.98 9,224,867.98

149,212.56 149,212.56

2.2.1.2.2.5 USR Marsh Construction 14.32 MO 2,136,723.84 2,136,723.84

490.62 490.62

2.2.1.2.2.6 USR Marsh Grade Stakes 1,235.00 EA 605,921.21 605,921.21

50,526.76 50,526.76

2.2.1.2.2.7 USR Survey Crew - Offshore 14.32 MO 723,543.25 723,543.25

29,937.08 29,937.08

2.2.1.2.2.8 USR Survey Crew - Onshore 14.32 MO 428,698.93 428,698.93

116,880.03 116,880.03

2.2.1.2.2.9 USR Pipeline Crew - Offshore 14.32 MO 1,673,722.01 1,673,722.01

67,020.55 67,020.55

2.2.1.2.2.10 USR Pipeline Crew - Shore 14.32 MO 959,734.22 959,734.22

3,394,900.00 3,394,900.00

2.2.1.2.3 02B-3 Access Channel 1.00 EA 3,394,900.00 3,394,900.00

85.00 85.00

2.2.1.2.3.1 USR Access Channel 39,940.00 LF 3,394,900.00 3,394,900.00

4,096,837.50 4,096,837.50

2.2.1.2.4 02B-4 Containment Dike 1.00 EA 4,096,837.50 4,096,837.50

52.50 52.50

2.2.1.2.4.1 USR Containment Dike 78,035.00 LF 4,096,837.50 4,096,837.50

575,656.25 575,656.25

2.2.1.2.5 02B-5 Sand Fencing 1.00 EA 575,656.25 575,656.25

16.25 16.25

2.2.1.2.5.1 USR Sand Fencing 35,425.00 LF 575,656.25 575,656.25

6,522,801.35 6,522,801.35

2.2.1.2.6 02B-6 Vegetative Plantings 1.00 EA 6,522,801.35 6,522,801.35

1,994,593.00 1,994,593.00

2.2.1.2.6.1 02B-6-1 Plantings - TY1 1.00 EA 1,994,593.00 1,994,593.00

2.2.1.2.6.1.1 USR Planting Mob/Demob - TY1 1.00 LS 20,000.00 20,000.00

100.00 100.00

2.2.1.2.6.1.2 USR Aerial Seeding - TY1 317.00 ACR 31,700.00 31,700.00

9.00 9.00

2.2.1.2.6.1.3 USR Dune/Swale Area - TY1 215,877.00 EA 1,942,893.00 1,942,893.00

2,897,526.40 2,897,526.40

2.2.1.2.6.2 02B-6-2 Plantings - TY2 1.00 EA 2,897,526.40 2,897,526.40

2.2.1.2.6.2.1 USR Planting Mob/Demob - TY2 1.00 LS 20,000.00 20,000.00

9.00 9.00

2.2.1.2.6.2.2 USR Woody Species - TY2 140,760.00 EA 1,266,840.00 1,266,840.00

4.45 4.45


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 14

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

2.2.1.2.6.2.3 USR Marsh Area - TY2 361,952.00 EA 1,610,686.40 1,610,686.40

1,630,681.95 1,630,681.95

2.2.1.2.6.3 02B-6-3 Plantings - TY3 1.00 EA 1,630,681.95 1,630,681.95

2.2.1.2.6.3.1 USR Planting Mob/Demob - TY3 1.00 LS 20,000.00 20,000.00

4.45 4.45

2.2.1.2.6.3.2 USR Marsh Area - TY3 361,951.00 EA 1,610,681.95 1,610,681.95

11,121,836.45 11,121,836.45

2.3 30 Planning, Engineering & Design 1.00 EA 11,121,836.45 11,121,836.45

2.3.1 USR PED 1.00 LS 11,121,836.45 11,121,836.45

11,121,836.45 11,121,836.45

2.4 31 Construction Management 1.00 EA 11,121,836.45 11,121,836.45

2.4.1 USR Construction Management 1.00 LS 11,121,836.45 11,121,836.45

784,322.71 784,322.71

3 Contract #3 - TY10 Terminal Groin O&M 1.00 EA 784,322.71 784,322.71

50,000.00 50,000.00

3.1 01 Lands & Damages 1.00 EA 50,000.00 50,000.00

50,000.00 50,000.00

3.1.1 USR 01A Acquisitions / Interagency Donations 1.00 EA 50,000.00 50,000.00

611,935.59 611,935.59

3.2 10 Raccoon Is. Terminal Groin O&M 1.00 EA 611,935.59 611,935.59

49,460.68 49,460.68

3.2.1 USR Survey Crew - Groin 0.92 MO 45,553.29 45,553.29

13,214.09 13,214.09

3.2.2 USR Quality Control Inspector 0.23 MO 3,039.24 3,039.24

69.38 69.38

3.2.3 USR Rip-Rap Rock 5,237.00 TON 363,343.06 363,343.06

200,000.00 200,000.00

3.2.4 USR Mob/Demob 1.00 EA 200,000.00 200,000.00

61,193.56 61,193.56

3.3 30 Planning, Engineering & Design 1.00 EA 61,193.56 61,193.56

3.3.1 USR PED (TY10 Terminal Groin O&M) 1.00 LS 61,193.56 61,193.56

61,193.56 61,193.56

3.4 31 Construction Management 1.00 EA 61,193.56 61,193.56

3.4.1 USR Construction Management (TY10 Terminal Groin O&M) 1.00 LS 61,193.56 61,193.56

78,321,523.45 78,321,523.45

4 Contract #4 - Renourishment TY20 - Whiskey Island 1.00 EA 78,321,523.45 78,321,523.45

50,000.00 50,000.00

4.1 01 Lands and Damages 1.00 EA 50,000.00 50,000.00

50,000.00 50,000.00

4.1.1 USR 01A Acquisitions / Interagency Donations 1.00 EA 50,000.00 50,000.00


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 15

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

71,155,930.41 71,155,930.41

4.2 17 Beach Replenishment 1.00 EA 71,155,930.41 71,155,930.41

71,155,930.41 71,155,930.41

4.2.1 02 Beach Construction 1.00 EA 71,155,930.41 71,155,930.41

5,555,443.35 5,555,443.35

4.2.1.1 02A Mobilization / Demobilization 1.00 EA 5,555,443.35 5,555,443.35

4.2.1.1.1 USR 02A-2 Dredge Mob / Demob 1.00 LS 1,026,030.14 1,026,030.14

24,540.32 24,540.32

4.2.1.1.2 USR 02A-3 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

151,176.64 151,176.64

4.2.1.1.3 USR 02A-4 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.25

2,281,996.45 2,281,996.45

4.2.1.1.1 02A-1 Pre-layout/Pick-up Pipeline 1.00 EA 2,281,996.45 2,281,996.45

511,957.13 511,957.13

4.2.1.1.1.1 02A-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 511,957.13 511,957.13

29.47 29.47

4.2.1.1.1.1.1 USR Pre-lay Shore Pipeline 5,656.00 LF 166,658.99 166,658.99

29.47 29.47

4.2.1.1.1.1.2 USR Pickup Shore Pipeline 11,071.00 LF 326,216.70 326,216.70

349.15 349.15

4.2.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 11.31 DAY 3,949.55 3,949.55

683.40 683.40

4.2.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 22.14 DAY 15,131.89 15,131.89

28.14 28.14

4.2.1.1.1.2 02A-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 1,770,039.32 1,770,039.32

7.58 7.58

4.2.1.1.1.2.1 USR Pre-lay Submerged Pipeline 62,908.00 LF 476,931.96 476,931.96

7.61 7.61

4.2.1.1.1.2.2 USR Pickup Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

9,708.27 9,708.27

4.2.1.1.1.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

9,708.27 9,708.27

4.2.1.1.1.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

65,600,487.06 65,600,487.06

4.2.1.2 02B Whiskey Island Renourishment 1.00 EA 65,600,487.06 65,600,487.06

63,284,139.31 63,284,139.31

4.2.1.2.1 02B-1 Beach/Dune Fill Renourishment 1.00 EA 63,284,139.31 63,284,139.31

6.97 6.97

4.2.1.2.1.1 USR Beach/Dune Fill 8,330,215.00 CY 58,064,427.87 58,064,427.87


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 16

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

223,915.42 223,915.42

4.2.1.2.1.2 USR Beach/Dune Construction 10.69 MO 2,393,655.86 2,393,655.86

50,526.76 50,526.76

4.2.1.2.1.3 USR Survey Crew - Offshore 10.69 MO 540,131.10 540,131.10

29,937.08 29,937.08

4.2.1.2.1.4 USR Survey Crew - Onshore 10.69 MO 320,027.34 320,027.34

116,880.03 116,880.03

4.2.1.2.1.5 USR Pipeline Crew - Offshore 10.69 MO 1,249,447.51 1,249,447.51

67,020.55 67,020.55

4.2.1.2.1.6 USR Pipeline Crew - Shore 10.69 MO 716,449.64 716,449.64

170,000.00 170,000.00

4.2.1.2.2 02B-2 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

4.2.1.2.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

940,695.00 940,695.00

4.2.1.2.3 02B-3 Containment Dike Renourishment 1.00 EA 940,695.00 940,695.00

52.50 52.50

4.2.1.2.3.1 USR Containment Dike 17,918.00 LF 940,695.00 940,695.00

293,718.75 293,718.75

4.2.1.2.4 02B-4 Sand Fencing Renourishment 1.00 EA 293,718.75 293,718.75

16.25 16.25

4.2.1.2.4.1 USR Sand Fencing 18,075.00 LF 293,718.75 293,718.75

911,934.00 911,934.00

4.2.1.2.5 02B-5 Vegetative Plantings Renourishment 1.00 EA 911,934.00 911,934.00

779,938.00 779,938.00

4.2.1.2.5.1 02B-5-1 Plantings - TY21 1.00 EA 779,938.00 779,938.00

4.2.1.2.5.1.1 USR Planting Mob/Demob - TY21 1.00 LS 20,000.00 20,000.00

100.00 100.00

4.2.1.2.5.1.2 USR Aerial Seeding - TY21 122.00 ACR 12,200.00 12,200.00

9.00 9.00

4.2.1.2.5.1.3 USR Dune/Swale Area - TY21 83,082.00 EA 747,738.00 747,738.00

131,996.00 131,996.00

4.2.1.2.5.2 02B-5-2 Plantings - TY22 1.00 EA 131,996.00 131,996.00

4.2.1.2.5.2.1 USR Planting Mob/Demob - TY22 1.00 LS 20,000.00 20,000.00

9.00 9.00

4.2.1.2.5.2.2 USR Woody Species - TY22 12,444.00 EA 111,996.00 111,996.00

3,557,796.52 3,557,796.52

4.3 30 Planning, Engineering & Design 1.00 EA 3,557,796.52 3,557,796.52

3,557,796.52 3,557,796.52

4.3.1 USR PED (TY20 Renourishment) 1.00 EA 3,557,796.52 3,557,796.52


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 17

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

3,557,796.52 3,557,796.52

4.4 31 Construction Management 1.00 EA 3,557,796.52 3,557,796.52

3,557,796.52 3,557,796.52

4.4.1 USR Construction Management (TY20 Renourishment) 1.00 EA 3,557,796.52 3,557,796.52

53,400,433.05 53,400,433.05

5 Contract #5 - Renourishment TY25 - Trinity Island 1.00 EA 53,400,433.05 53,400,433.05

50,000.00 50,000.00

5.1 01 Lands and Damages 1.00 EA 50,000.00 50,000.00

5.1.1 USR 01A Acquisitions / Interagency Donations 1.00 LS 50,000.00 50,000.00

48,500,393.69 48,500,393.69

5.2 17 Beach Replenishment 1.00 EA 48,500,393.69 48,500,393.69

48,500,393.69 48,500,393.69

5.2.1 02 Beach Construction 1.00 EA 48,500,393.69 48,500,393.69

6,914,140.71 6,914,140.71

5.2.1.1 02A Mobilization / Demobilization 1.00 EA 6,914,140.71 6,914,140.71

24,540.32 24,540.32

5.2.1.1.1 USR 02A-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

151,176.64 151,176.64

5.2.1.1.2 USR 02A-3 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.255.2.1.1.3 USR 02A-4 Dredge Mob/Demob 1.00 LS 1,067,510.09 1,067,510.09

3,599,213.86 3,599,213.86

5.2.1.1.1 02A-1 Pre-layout/Pick-up Pipeline 1.00 EA 3,599,213.86 3,599,213.86

1,196,251.99 1,196,251.99

5.2.1.1.1.1 02A-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 1,196,251.99 1,196,251.99

29.47 29.47

5.2.1.1.1.1.1 USR Pre-lay Shore Pipeline 13,088.00 LF 385,649.37 385,649.37

29.47 29.47

5.2.1.1.1.1.2 USR Pickup Shore Pipeline 24,315.00 LF 716,462.75 716,462.75

807.92 807.92

5.2.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 26.18 DAY 21,148.02 21,148.02

1,500.96 1,500.96

5.2.1.1.1.1.4 USR Pickup 30-inch Shore Pipeline Standby Cost 48.63 DAY 72,991.86 72,991.86

38.20 38.20

5.2.1.1.1.2 02A-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 2,402,961.87 2,402,961.87

7.58 7.58

5.2.1.1.1.2.1 USR Pre-lay Submerged Pipeline 77,280.00 LF 585,892.13 585,892.13

7.61 7.61

5.2.1.1.1.2.2 USR Pickup Submerged Pipeline 77,280.00 LF 588,191.47 588,191.47

11,926.23 11,926.23

5.2.1.1.1.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 51.52 DAY 614,439.13 614,439.13


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 18

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

11,926.23 11,926.23

5.2.1.1.1.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 51.52 DAY 614,439.13 614,439.13

41,586,252.98 41,586,252.98

5.2.1.2 02B Trinity Island Renourishment 1.00 EA 41,586,252.98 41,586,252.98

38,378,132.48 38,378,132.48

5.2.1.2.1 02B-1 Beach/Dune Fill Renourishment 1.00 EA 38,378,132.48 38,378,132.48

9.38 9.38

5.2.1.2.1.1 USR Beach/Dune Fill 3,813,885.00 CY 35,756,069.77 35,756,069.77

223,915.42 223,915.42

5.2.1.2.1.2 USR Beach/Dune Construction 5.37 MO 1,202,425.82 1,202,425.82

50,526.76 50,526.76

5.2.1.2.1.3 USR Survey Crew - Offshore 5.37 MO 271,328.72 271,328.72

29,937.08 29,937.08

5.2.1.2.1.4 USR Survey Crew - Onshore 5.37 MO 160,762.10 160,762.10

116,880.03 116,880.03

5.2.1.2.1.5 USR Pipeline Crew - Offshore 5.37 MO 627,645.75 627,645.75

67,020.55 67,020.55

5.2.1.2.1.6 USR Pipeline Crew - Shore 5.37 MO 359,900.33 359,900.33

170,000.00 170,000.00

5.2.1.2.2 02B-2 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

5.2.1.2.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

1,175,580.00 1,175,580.00

5.2.1.2.3 02B-3 Containment Dike Renourishment 1.00 EA 1,175,580.00 1,175,580.00

52.50 52.50

5.2.1.2.3.1 USR Containment Dike 22,392.00 LF 1,175,580.00 1,175,580.00

364,552.50 364,552.50

5.2.1.2.4 02B-4 Sand Fencing Renourishment 1.00 EA 364,552.50 364,552.50

16.25 16.25

5.2.1.2.4.1 USR Sand Fencing 22,434.00 LF 364,552.50 364,552.50

1,497,988.00 1,497,988.00

5.2.1.2.5 02B-5 Vegetative Plantings Renourishment 1.00 EA 1,497,988.00 1,497,988.00

1,290,716.00 1,290,716.00

5.2.1.2.5.1 02B-5-1 Plantings - TY26 1.00 EA 1,290,716.00 1,290,716.00

5.2.1.2.5.1.1 USR Planting Mob/Demob - TY26 1.00 LS 20,000.00 20,000.00

100.00 100.00

5.2.1.2.5.1.2 USR Aerial Seeding - TY26 204.00 ACR 20,400.00 20,400.00

9.00 9.00

5.2.1.2.5.1.3 USR Dune/Swale Area - TY26 138,924.00 EA 1,250,316.00 1,250,316.00


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 19

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

207,272.00 207,272.00

5.2.1.2.5.2 02B-5-2 Plantings - TY27 1.00 EA 207,272.00 207,272.00

5.2.1.2.5.2.1 USR Planting Mob/Demob - TY27 1.00 LS 20,000.00 20,000.00

9.00 9.00

5.2.1.2.5.2.2 USR Woody Species - TY27 20,808.00 EA 187,272.00 187,272.00

2,425,019.68 2,425,019.68

5.3 30 Planning, Engineering & Design 1.00 EA 2,425,019.68 2,425,019.68

5.3.1 USR PED (TY25 Renourishment) 1.00 LS 2,425,019.68 2,425,019.68

2,425,019.68 2,425,019.68

5.4 31 Construction Management 1.00 EA 2,425,019.68 2,425,019.68

5.4.1 USR Construction Management (TY25 Renourishment) 1.00 LS 2,425,019.68 2,425,019.68

40,209,836.52 40,209,836.52

6 Contract #6 - Renourishment TY30 - Raccoon & Timbalier Islands 1.00 EA 40,209,836.52 40,209,836.52

432,308.00 432,308.00

6.1 01 Lands and Damages 1.00 EA 432,308.00 432,308.00

6.1.1 USR 01A Acquisitions / Interagency Donations 1.00 LS 432,308.00 432,308.00

36,161,389.56 36,161,389.56

6.2 17 Beach Replenishment 1.00 EA 36,161,389.56 36,161,389.56

36,161,389.56 36,161,389.56

6.2.1 02 Beach Construction 1.00 EA 36,161,389.56 36,161,389.56

10,319,159.46 10,319,159.46

6.2.1.1 02A Mobilization / Demobilization 1.00 EA 10,319,159.46 10,319,159.46

151,176.64 151,176.64

6.2.1.1.1 USR 02A-3 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.256.2.1.1.2 USR 02A-4 Dredge Mob 1.00 LS 716,455.75 716,455.756.2.1.1.3 USR 02A-5 Dredge Demob/Mob BA Relocation & Final Demob 1.00 LS 364,085.79 364,085.79

4,457,059.94 4,457,059.94

6.2.1.1.1 02A-1 Timbalier Island Renourishment 1.00 EA 4,457,059.94 4,457,059.94

24,540.32 24,540.32

6.2.1.1.1.1 USR 02A-1-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

4,265,645.43 4,265,645.43

6.2.1.1.1.1 02A-1-1 Pre-layout/Pick-up Pipeline 1.00 EA 4,265,645.43 4,265,645.43

1,069,408.36 1,069,408.36

6.2.1.1.1.1.1 02A-1-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 1,069,408.36 1,069,408.36

29.47 29.47

6.2.1.1.1.1.1.1 USR Pre-lay Shore Pipeline 12,068.00 LF 355,594.18 355,594.18

29.47 29.47

6.2.1.1.1.1.1.2 USR Pickup Shore Pipeline 21,925.00 LF 646,039.30 646,039.30

349.15 349.15

6.2.1.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 24.14 DAY 8,427.02 8,427.02


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 20

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1,353.43 1,353.43

6.2.1.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 43.85 DAY 59,347.86 59,347.86

50.81 50.81

6.2.1.1.1.1.2 02A-1-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 3,196,237.07 3,196,237.07

7.58 7.58

6.2.1.1.1.1.2.1 USR Pre-lay Submerged Pipeline 85,206.00 LF 645,982.47 645,982.47

7.61 7.61

6.2.1.1.1.1.2.2 USR Pickup Submerged Pipeline 85,206.00 LF 648,517.63 648,517.63

13,149.40 13,149.40

6.2.1.1.1.1.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 56.80 DAY 746,938.76 746,938.76

13,149.40 13,149.40

6.2.1.1.1.1.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 56.80 DAY 746,938.76 746,938.76

7,180.12 7,180.12

6.2.1.1.1.1.2.5 USR Pickup Dredge Standby Cost 56.80 DAY 407,859.46 407,859.46

2,725,555.73 2,725,555.73

6.2.1.1.2 02A-2 Raccoon Island Renourishment 1.00 EA 2,725,555.73 2,725,555.73

24,540.32 24,540.32

6.2.1.1.2.1 USR 02A-2-2 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

2,534,141.21 2,534,141.21

6.2.1.1.2.1 02A-2-1 Pre-layout/Pick-up Pipeline 1.00 EA 2,534,141.21 2,534,141.21

738,886.42 738,886.42

6.2.1.1.2.1.1 02A-2-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 738,886.42 738,886.42

29.47 29.47

6.2.1.1.2.1.1.1 USR Pre-lay Shore Pipeline 10,183.00 LF 300,051.00 300,051.00

29.47 29.47

6.2.1.1.2.1.1.2 USR Pickup Shore Pipeline 13,675.00 LF 402,945.84 402,945.84

628.59 628.59

6.2.1.1.2.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 20.37 DAY 12,801.88 12,801.88

844.16 844.16

6.2.1.1.2.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 27.35 DAY 23,087.69 23,087.69

28.54 28.54

6.2.1.1.2.1.2 02A-2-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 1,795,254.79 1,795,254.79

7.58 7.58

6.2.1.1.2.1.2.1 USR Pre-lay Submerged Pipeline 56,721.00 LF 430,025.72 430,025.72

7.61 7.61

6.2.1.1.2.1.2.2 USR Pickup Submerged Pipeline 56,721.00 LF 431,713.36 431,713.36

8,753.46 8,753.46

6.2.1.1.2.1.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 37.81 DAY 331,003.36 331,003.36

8,753.46 8,753.46


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 21

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

6.2.1.1.2.1.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 37.81 DAY 331,003.36 331,003.36

7,180.12 7,180.12

6.2.1.1.2.1.2.5 USR Pre-lay Dredge Standby Cost 37.81 DAY 271,509.00 271,509.00

9,610,358.46 9,610,358.46

6.2.1.2 02B Timbalier Island Renourishment 1.00 EA 9,610,358.46 9,610,358.46

4,683,316.71 4,683,316.71

6.2.1.2.1 02B-1 Beach/Dune Fill Renourishment 1.00 EA 4,683,316.71 4,683,316.71

9.29 9.29

6.2.1.2.1.1 USR Beach/Dune Fill 470,203.00 CY 4,365,934.82 4,365,934.82

223,915.42 223,915.42

6.2.1.2.1.2 USR Beach/Dune Construction 0.65 MO 145,545.02 145,545.02

50,526.76 50,526.76

6.2.1.2.1.3 USR Survey Crew - Offshore 0.65 MO 32,842.40 32,842.40

29,937.08 29,937.08

6.2.1.2.1.4 USR Survey Crew - Onshore 0.65 MO 19,459.10 19,459.10

116,880.03 116,880.03

6.2.1.2.1.5 USR Pipeline Crew - Offshore 0.65 MO 75,972.02 75,972.02

67,020.55 67,020.55

6.2.1.2.1.6 USR Pipeline Crew - Shore 0.65 MO 43,563.35 43,563.35

170,000.00 170,000.00

6.2.1.2.2 02B-2 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

6.2.1.2.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

1,861,492.50 1,861,492.50

6.2.1.2.3 02B-3 Containment Dike Renourishment 1.00 EA 1,861,492.50 1,861,492.50

52.50 52.50

6.2.1.2.3.1 USR Containment Dike 35,457.00 LF 1,861,492.50 1,861,492.50

575,656.25 575,656.25

6.2.1.2.4 02B-4 Sand Fencing Renourishment 1.00 EA 575,656.25 575,656.25

16.25 16.25

6.2.1.2.4.1 USR Sand Fencing 35,425.00 LF 575,656.25 575,656.25

2,319,893.00 2,319,893.00

6.2.1.2.5 02B-5 Vegetative Plantings Renourishment 1.00 EA 2,319,893.00 2,319,893.00

2,007,051.00 2,007,051.00

6.2.1.2.5.1 02B-5-1 Plantings - TY31 1.00 EA 2,007,051.00 2,007,051.00

6.2.1.2.5.1.1 USR Planting Mob/Demob - TY31 1.00 LS 20,000.00 20,000.00

100.00 100.00

6.2.1.2.5.1.2 USR Aerial Seeding - TY31 319.00 ACR 31,900.00 31,900.00

9.00 9.00

6.2.1.2.5.1.3 USR Dune/Swale Area - TY31 217,239.00 EA 1,955,151.00 1,955,151.00


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 22

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

312,842.00 312,842.00

6.2.1.2.5.2 02B-5-2 Plantings - TY32 1.00 EA 312,842.00 312,842.00

6.2.1.2.5.2.1 USR Planting Mob/Demob - TY32 1.00 LS 20,000.00 20,000.00

9.00 9.00

6.2.1.2.5.2.2 USR Woody Species - TY32 32,538.00 EA 292,842.00 292,842.00

16,231,871.64 16,231,871.64

6.2.1.3 02C Raccoon Island Renourishment 1.00 EA 16,231,871.64 16,231,871.64

14,301,755.31 14,301,755.31

6.2.1.3.1 02C-1 Beach/Dune Fill Renourishment 1.00 EA 14,301,755.31 14,301,755.31

6.74 6.74

6.2.1.3.1.1 USR Beach/Dune Fill 1,946,212.00 CY 13,115,235.31 13,115,235.31

223,915.42 223,915.42

6.2.1.3.1.2 USR Beach/Dune Construction 2.43 MO 544,114.48 544,114.48

50,526.76 50,526.76

6.2.1.3.1.3 USR Survey Crew - Offshore 2.43 MO 122,780.03 122,780.03

29,937.08 29,937.08

6.2.1.3.1.4 USR Survey Crew - Onshore 2.43 MO 72,747.09 72,747.09

116,880.03 116,880.03

6.2.1.3.1.5 USR Pipeline Crew - Offshore 2.43 MO 284,018.47 284,018.47

67,020.55 67,020.55

6.2.1.3.1.6 USR Pipeline Crew - Shore 2.43 MO 162,859.93 162,859.93

170,000.00 170,000.00

6.2.1.3.2 02C-2 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

6.2.1.3.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

839,685.00 839,685.00

6.2.1.3.3 02C-3 Containment Dike Renourishment 1.00 EA 839,685.00 839,685.00

52.50 52.50

6.2.1.3.3.1 USR Containment Dike 15,994.00 LF 839,685.00 839,685.00

198,022.50 198,022.50

6.2.1.3.4 02C-4 Sand Fencing Renourishment 1.00 EA 198,022.50 198,022.50

16.25 16.25

6.2.1.3.4.1 USR Sand Fencing 12,186.00 LF 198,022.50 198,022.50

722,408.83 722,408.83

6.2.1.3.5 02C-5 Vegetative Plantings Renourishment 1.00 EA 722,408.83 722,408.83

610,505.30 610,505.30

6.2.1.3.5.1 02C-5-1 Plantings - TY31 1.00 EA 610,505.30 610,505.30

6.2.1.3.5.1.1 USR Planting Mob/Demob - TY31 1.00 LS 25,720.81 25,720.81

128.60 128.60

6.2.1.3.5.1.2 USR Aerial Seeding - TY31 73.00 ACR 9,388.10 9,388.10


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 23

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

11.57 11.57

6.2.1.3.5.1.3 USR Dune/Swale Area - TY31 49,713.00 EA 575,396.39 575,396.39

111,903.53 111,903.53

6.2.1.3.5.2 02C-5-2 Plantings - TY32 1.00 EA 111,903.53 111,903.53

6.2.1.3.5.2.1 USR Planting Mob/Demob - TY2 1.00 LS 25,720.81 25,720.81

11.57 11.57

6.2.1.3.5.2.2 USR Woody Species - TY2 7,446.00 EA 86,182.72 86,182.72

1,808,069.48 1,808,069.48

6.3 30 Planning, Engineering & Design 1.00 EA 1,808,069.48 1,808,069.48

6.3.1 USR PED (TY30 Renourishment) 1.00 LS 1,808,069.48 1,808,069.48

1,808,069.48 1,808,069.48

6.4 31 Construction Management 1.00 EA 1,808,069.48 1,808,069.48

6.4.1 USR Construction Management (TY30 Renourishment) 1.00 LS 1,808,069.48 1,808,069.48

61,846,340.47 61,846,340.47

7 Contract #7 - Renourishment TY40 - Whiskey Island 1.00 EA 61,846,340.47 61,846,340.47

50,000.00 50,000.00

7.1 01 Lands and Damages 1.00 EA 50,000.00 50,000.00

50,000.00 50,000.00

7.1.1 USR 01A Acquisitions / Interagency Donations 1.00 EA 50,000.00 50,000.00

56,178,491.33 56,178,491.33

7.2 17 Beach Replenishment 1.00 EA 56,178,491.33 56,178,491.33

56,178,491.33 56,178,491.33

7.2.1 02 Beach Construction 1.00 EA 56,178,491.33 56,178,491.33

5,555,443.35 5,555,443.35

7.2.1.1 02A Mobilization / Demobilization 1.00 EA 5,555,443.35 5,555,443.35

7.2.1.1.1 USR 02A-2 Dredge Mob / Demob 1.00 LS 1,026,030.14 1,026,030.14

24,540.32 24,540.32

7.2.1.1.2 USR 02A-3 Mob/Demob Crew & Equipment 7.80 DAY 191,414.52 191,414.52

151,176.64 151,176.64

7.2.1.1.3 USR 02A-4 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.25

2,281,996.45 2,281,996.45

7.2.1.1.1 02A-1 Pre-layout/Pick-up Pipeline 1.00 EA 2,281,996.45 2,281,996.45

511,957.13 511,957.13

7.2.1.1.1.1 02A-1-1 Shore Pre-layout/Pick-up Pipeline 1.00 EA 511,957.13 511,957.13

29.47 29.47

7.2.1.1.1.1.1 USR Pre-lay Shore Pipeline 5,656.00 LF 166,658.99 166,658.99

29.47 29.47

7.2.1.1.1.1.2 USR Pickup Shore Pipeline 11,071.00 LF 326,216.70 326,216.70

349.15 349.15

7.2.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 11.31 DAY 3,949.55 3,949.55


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 24

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

683.40 683.40

7.2.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 22.14 DAY 15,131.89 15,131.89

28.14 28.14

7.2.1.1.1.2 02A-1-2 Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 1,770,039.32 1,770,039.32

7.58 7.58

7.2.1.1.1.2.1 USR Pre-lay Submerged Pipeline 62,908.00 LF 476,931.96 476,931.96

7.61 7.61

7.2.1.1.1.2.2 USR Pickup Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

9,708.27 9,708.27

7.2.1.1.1.2.3 USR Pre-lay 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

9,708.27 9,708.27

7.2.1.1.1.2.4 USR Pickup 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

50,623,047.98 50,623,047.98

7.2.1.2 02B Whiskey Island Renourishment (Plan B) 1.00 EA 50,623,047.98 50,623,047.98

48,313,283.98 48,313,283.98

7.2.1.2.1 01 Beach/Dune Fill Renourishment 1.00 EA 48,313,283.98 48,313,283.98

6.97 6.97

7.2.1.2.1.1 USR Beach/Dune Fill 6,359,650.00 CY 44,328,920.53 44,328,920.53

223,915.42 223,915.42

7.2.1.2.1.2 USR Beach/Dune Construction 8.16 MO 1,827,149.84 1,827,149.84

50,526.76 50,526.76

7.2.1.2.1.3 USR Survey Crew - Offshore 8.16 MO 412,298.39 412,298.39

29,937.08 29,937.08

7.2.1.2.1.4 USR Survey Crew - Onshore 8.16 MO 244,286.54 244,286.54

116,880.03 116,880.03

7.2.1.2.1.5 USR Pipeline Crew - Offshore 8.16 MO 953,741.03 953,741.03

67,020.55 67,020.55

7.2.1.2.1.6 USR Pipeline Crew - Shore 8.16 MO 546,887.66 546,887.66

170,000.00 170,000.00

7.2.1.2.2 02 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

7.2.1.2.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

935,655.00 935,655.00

7.2.1.2.3 03 Containment Dike Renourishment 1.00 EA 935,655.00 935,655.00

52.50 52.50

7.2.1.2.3.1 USR Containment Dike 17,822.00 LF 935,655.00 935,655.00

292,175.00 292,175.00

7.2.1.2.4 04 Sand Fencing Renourishment 1.00 EA 292,175.00 292,175.00

16.25 16.25


Eff. Date 10/2009 Project: LCA Terrebonne Basin Barrier Shoreline Restoration - NER Plan LCA TBBSR Bid Schedule Summary Page 25

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

7.2.1.2.4.1 USR Sand Fencing 17,980.00 LF 292,175.00 292,175.00

911,934.00 911,934.00

7.2.1.2.5 05 Vegetative Plantings Renourishment 1.00 EA 911,934.00 911,934.00

779,938.00 779,938.00

7.2.1.2.5.1 05a Plantings - TY41 1.00 EA 779,938.00 779,938.00

7.2.1.2.5.1.1 USR Planting Mob/Demob - TY41 1.00 LS 20,000.00 20,000.00

100.00 100.00

7.2.1.2.5.1.2 USR Aerial Seeding - TY41 122.00 ACR 12,200.00 12,200.00

9.00 9.00

7.2.1.2.5.1.3 USR Dune/Swale Area - TY41 83,082.00 EA 747,738.00 747,738.00

131,996.00 131,996.00

7.2.1.2.5.2 05b Plantings - TY42 1.00 EA 131,996.00 131,996.00

7.2.1.2.5.2.1 USR Planting Mob/Demob - TY42 1.00 LS 20,000.00 20,000.00

9.00 9.00

7.2.1.2.5.2.2 USR Woody Species - TY42 12,444.00 EA 111,996.00 111,996.00

2,808,924.57 2,808,924.57

7.3 30 Planning, Engineering & Design 1.00 EA 2,808,924.57 2,808,924.57

2,808,924.57 2,808,924.57

7.3.1 USR PED (TY40 Renourishment) 1.00 EA 2,808,924.57 2,808,924.57

2,808,924.57 2,808,924.57

7.4 31 Construction Management 1.00 EA 2,808,924.57 2,808,924.57

2,808,924.57 2,808,924.57

7.4.1 USR Construction Management (TY40 Renourishment) 1.00 EA 2,808,924.57 2,808,924.57


LCA Terrebonne Basin Barrier Shoreline Restoration

MCACES Estimate for the First Component of Construction

INTRODUCTION

The LCA Terrebonne Basin Barrier Shoreline Restoration Study (LCA TBBSR) was

identified in the Louisiana Coastal Area, (LCA), Louisiana Ecosystem Restoration Study

(USACE 2004; 2004 LCA Plan). The 2004 LCA Plan was recommended to Congress by

a Chief of Engineers report dated January 31, 2005, which called for a coordinated,

feasible solution to the identified critical water resource problems and opportunities in

coastal Louisiana.

FIRST COMPONENT OF CONSTRUCTION MCACES SUMMARY

The first component of construction consists of initial restoration of Whiskey Island to its

minimal geomorphologic form and ecologic function along with five (5) years of

advanced fill, followed by renourishment to the same plan in Target Year (TY) 20 and a

second renourishment to the minimum geomorphologic form and ecological function

only, in TY40. The maintenance costs for both events will include mobilization /

demobilization, surveying, beach/dune fill placement, sand fencing, vegetation planting

(dune/supratidal platform only), planning, engineering and design (PED), and

construction administration.

The initial restoration will utilize beach/dune and marsh material from Ship Shoal blocks

88, 89, 94, and 95, and a nearshore borrow area identified and studied for the Whiskey

Island TE-50 marsh creation project. The nearshore borrow area has been designated

Whiskey Island Restoration Borrow Area 3 (Whiskey BA-3A). Both borrow areas have

published geotechnical and geophysical survey data collected for other barrier island

restoration efforts. Analyses of this data lead to the development of dredge-to-fill ratios

of 1.13:1 for Ship Shoal as beach/dune fill material and 1.6:1 for Whiskey BA-3A as

marsh fill material. Renourishment events will utilize beach/dune material from Ship

Shoal blocks 88, 89, 94, and 95.

Initial restoration fill quantities for the beach/dune and marsh components of are 8.3

million cubic yards and 579,724 cubic yards, respectively. Renourishment beach/dune fill

quantities for TY20 are estimated to be 8.3 million cubic yards and in TY40 are estimated

to be 6.4 million cubic yards

For the beach/dune area, a 30" cutterhead dredge would be used with the assistance of

booster pumps to transport the material from the Ship Shoal borrow area to the

beach/dune fill template. The material will then be worked, shaped, and graded by

bulldozers. For the marsh area, the material would be pumped from Whiskey BA-3A by

a 30" cutterhead dredge with the assistance of a booster pump. The discharge pipe for

marsh fill will be directed within the marsh fill template through movements of the

pipeline with the assistance of a marsh backhoe. Containment dikes would be constructed

around the perimeter of the marsh fill template to retain the sediment. Sediment for the


containment dikes will be dredged from existing material alongside the dike alignment by

a barge mounted clam shell dredge. Access channel and containment dike costs were

developed from past construction projects as a per linear foot unit cost. This method was

chosen because the survey data available was widely spaced (~1500 feet) preventing the

designers of the feasibility level construction templates from determining definitive cubic

yard excavation volumes. Construction operations would be completed in a manner that

will minimize turbidity of the water at the dredge site and the discharge site.

Sand fencing would be installed in a single row along the entire length of the dune feature

for Whiskey Island. Vegetative plantings will include a variety of native species. The

recommended planting density is no greater than 8-foot centers and follows

recommendations developed for restoration efforts in the area.

FIRST COMPONENT OF CONSTRUCTION MII COSTING ELEMENT

DESCRIPTIONS

[01] Lands and Damages

Whiskey Island is solely owned by the State of Louisiana. $50,000 was included for

interagency donations paperwork at the suggestion of the LCA Real Estate Consultant.

[06] Fish and Wildlife (Initial Restoration Only)

This feature code is included to capture the cost associated with the Adaptive

Management and Monitoring Plan (AMP) and is inclusive of cost contingency and

escalation. The cost elements of the AMP include program setup, implementation, and

post construction monitoring. Cost associated with AMP setup coincides with the PED

of the project and includes initial monitoring, database development, and the creation of

the detailed AMP. Implementation costs are associated with administering the AMP

during construction and the post monitoring phase. Post construction monitoring costs

were developed by the development team and are planned to support the monitoring for

10 years post-construction of the initial restoration.

[17] Beach Replenishment

This feature code includes all the elements of construction on the island. Details of the

individual elements are listed below.

Shore Pre-layout/Pick-up Pipeline: This item is for all equipment, labor and

materials required for the installation, standby, and removal of the shore pipeline.

Submerged Pre-layout/Pick-up Pipeline for Beach/Dune Fill: This item is for all

equipment, labor and materials required for the installation, standby, and removal

of the submerged pipeline for beach / dune fill. It includes submerged pipeline

pre-layout of 62,908ft of pipeline from Ship Shoal to Whiskey Island for

beach/dune fill. USACE review of prior projects indicates the crews can pre-lay


1,500ft of pipeline per day while working 12 hours per day. Submerged pipeline

pick-up is for the extraction of the submerged pipeline from Ship Shoal to

Whiskey Island.

Submerged Pre-layout/Pick-up Pipeline for Marsh Fill (Initial Restoration Only):

This item is for all equipment, labor and materials required for the installation,

standby, and removal of the submerged pipeline for marsh fill. It includes

submerged pipeline pre-layout of 34288' of submerged pipeline from Whiskey

BA-3A to Whiskey Island. USACE review of prior projects indicates the crews

can pre-lay of 1500' of pipeline per day while working 12 hours per day.

Submerged pipeline pick-up is for the final extraction of the submerged pipeline

from Whiskey BA-3A to Whiskey Island.

Dredge Mob/Demob: includes dredge, boosters, plant tugs/tenders, attendant

plant, pipeline standby cost, transfer of shore pipe and float hose on barge, and

work barges. Costs are from USACE CEDEP program.

Mob/Demob Crew & Equipment: This item is for all equipment, labor, and

materials required for the mobilization/demobilization of the shore equipment &

crews, pipeline handling equipment & crews. A time table developed for this

element is shown below.

Mob/Demob of crews and equipment:

Mob prep time: 1.0 day

Mobilize: 4.2 days

Prep for work: 0.5 days

Demobilize: 2.1 days.

Total time: 7.8 days (7.8 x 12 hrs/day = 94 hrs)

Mob/demob of the Marsh Backhoe(s): Allow 3 days at 10 hours/day (min

rental).

Mob/demob of dredge and pipeline are priced in separate item details.

Mob/Demob Pipeline: This item is for all equipment, labor and materials required

for the mob/demob of the floating and submerged pipeline. Only mob/demob of

the submerged and pontoon line will be paid for in this item detail. Mob/demob of

shore pipeline and float hose is included in the USACE CEDEP program for

dredge mob/demob. The submerged and floating pipeline is being mobilized

while in rafts of 6,000-ft bundles. Each raft will be towed by a 1,200 HP tug and

followed by a tender with a minimum of 300 HP. A time table developed for this

element is shown below.

Breakdown:

Home to Pipeline (Mob)*: 0.5 day (24 hrs/day)

Pipeline to Jobsite (Mob): 4.2 days


Jobsite to Home (Mob)*: 2.1 days

Home to Jobsite (Demob)*: 2.1 days

Jobsite to Pipeline Yard (Demob): 4.2 days

Pipeline Yard to Home (Demob)*: 0.5 day

Total pipeline mob/demob: 13.6 days

*Tug is not towing during these trips so it can travel at twice the speed

and thus reduce the travel time.

CEDEP inputs include:

78,000 linear feet of pipeline to be mobilized

Tugs required for pipeline: 1200 HP tugs = 13, 600HP tug/tender =

1 (min HP required), 300 HP tender = 12 (min HP required).

Less potential tugs in CEDEP plant mob/demob: 2-900 HP, 2- 600

HP, xx -300 HP. Tugs Requires: 13 - 1200 HP, 11 - 600 HP

rentals (assumes extra 0-900 HP and 2-600 HP avail from dredge

plant).

First Component of Construction

Beach/Dune Fill

Beach/Dune Fill: Unit price for beach/dune fill was developed in USACE

dredging program CEDEP. Quantities used in the MCACES cost estimate

are in place fill from feasibility level island designs on the gulf side of the

existing beach on Whiskey Island.

Beach/Dune Construction: This item detail is for crew and equipment for

fill placement, grading, and shaping of the beach/dune material.

Equipment includes two dozers with operators and a foreman for

24hrs/day. Foreman will oversee all fill area operations for beach and fill

including the shore pipeline crew. This crew is priced on a monthly basis

and includes the 2 dozers (1 D-5 LGP and 1 D-7 LGP equivalent). The

crews and equipment are assumed to work 2 - 12 hour shifts or 730 hours

per month.

Survey Crew - Offshore: This item detail is for the offshore survey crew

consisting of a Survey Chief, Rodman, and boat operator and includes a

survey vessel for equipment. The offshore survey crews will operate

during daylight hours for 12hrs/day and will conduct borrow area, access

channel and gulf beach face surveys during construction. The survey

vessel is assumed to work 50% of one 12 hour shift or 182.5 hrs/mo.

Survey crew labor is paid for full 12 hours shift or 365 hrs/mo.

Survey Crew - Onshore: This item detail is for the onshore fill area survey

crew consisting of a Survey Chief and two Rodmen. Onshore survey crew


will work 12hrs/day, 7 days a week and conduct surveys of fill template

areas. Equivalent crew work hours equal 365hrs/mo.

Pipeline Crew - Offshore: This item detail is for the equipment and crew

maintaining the submerged sections of the sediment pipeline during

construction. This crew and equipment are priced on a monthly basis. The

equipment is assumed to work 50% of one 12 hour shift or 182.5 hrs/mo.

Crew labor is paid for full 12 hours shift or 365 hrs/mo.

Pipeline Crew - Onshore: This item detail is for the equipment and crew

maintaining the submerged sections of the sediment pipeline during

construction. This crew and equipment are priced on a monthly basis. The

equipment is assumed to work 50% of one 12 hour shift or 182.5 hrs/mo.

Crew labor is paid for full 12 hours shift or 365 hrs/mo.

Marsh Fill (Initial Restoration Only)

Marsh Fill: Unit price for marsh fill developed in USACE dredging

program CEDEP. Marsh fill quantities are in place fill from feasibility

level island designs.

Marsh Construction: This item detail is for the equipment and crew for

marsh fill placement. Equipment includes a marsh backhoe with operator

operating for 12hrs/day. A laborer and general foreman are paid for 2 -

12hr shifts. Foreman will oversee all fill area operations for the marsh fill

including the shore pipeline crew. This crew is priced on a monthly basis.

The equipment includes one (1) marsh backhoe that is assumed to work

one 12 hour shift per day or 365 hrs/mo. Crew labor paid full time with the

marsh backhoe operator being paid with marsh backhoe rental.

Marsh Grade Stakes: Material cost includes grade stakes at an estimated

$350.00/stake. Stakes are to be spaced along each survey line (250ft

spacing) at an interval of 150ft. Quantity of grade stakes are estimated at

1.16 per acre. Marsh acres for calculated for Whiskey Plan C are 109.58

and would require an estimated 127 marsh grade stakes.

Access Channel

The Access Channel linear foot cost was derived from recent constructed

project bids. Items priced by historic bids are those bids submitted by the

prime dredging contractor. These bids already include all of the markups

associated with the prime sub-contracting the work. The cost from these

bids was escalated to 2009 price levels before unit price calculations.

Channel length is estimated from feasibility level island designs as the

length of the northern marsh containment dike (CDN). The final access

channel design lengths can not be determined until a more detailed survey

of the area is conducted for final design. The Access channel is to remain


un-filled after construction for vegetative plantings access and

maintenance operations of the containment dikes if required.

Containment Dike

The containment dike linear foot cost was derived from recently

constructed project bids. Items priced by historic bids are those bids

submitted by the prime dredging contractor. These bids already include all

of the markups associated with the prime sub-contracting the work. The

cost from these bids was escalated to 2009 price levels before unit price

calculations. The length of containment dikes is a summation of feasibility

level island design lengths of the northern marsh containment dike (CDN)

and beach/dune - marsh separation dike (CDS) for the initial restorations

and only that of the CDS for the renourishment events. Containment dikes

will be constructed of in-situ material with no weirs, armoring, or

structural bracing. Plantings of vegetative cover of dikes are included in

plantings of dune/swale and marsh fill areas.

Sand Fencing

Sand fencing length derived from feasibility level island design length of

the dune feature. Estimate was escalated to 2009 price levels before

computing unit price. Items priced by historic bids are those bids

submitted by the prime dredging contractor. These bids already include all

of the markups associated with the prime sub-contracting the work. The

sand fencing would require transport to the fill site by small marine vessel.

Unit prices include transport, materials, installation, equipment, and crews

Fencing Materials: Fencing shall be standard, weather resistant snow

fencing. Slats shall be made of No. 1 aspen or spruce measuring 3/8 inch

thick, 1-1/2 inch wide by 4 feet long. The distance between the slats shall

be 3 inches on center (50% porosity). The slats shall be painted with a

high quality red oxide stain. Post shall be 4 inch by 4 inch untreated #2

grade lumber 10 feet long driven 6 feet into the ground. They shall be

placed on 10 feet centers.

Vegetative Plantings

Vegetative planting species and planting schemes are consistent with

Louisiana past and planned restoration projects. Unit cost were developed

from an average of past restoration projects along the Louisiana Gulf

Coast. One such from a winning bid for Pass Chaland (BA-35) in 2008,

one from the average of submitted construction bids for East Grande Terre

(BA-30) in 2009, and one from feasibility design cost estimates from Shell

Island. All were escalated to 2009 price levels before computing unit

price. Plantings will be scheduled for the season of the year that promotes

the greatest survivability. No re-plantings for die-offs are considered for

this project.


Plantings in the first year following construction include plantings in the

following areas and described species:

Aerial Seeding: Aerial Seeding will be done over the dune/swale

habitat area (122 acres) if required by the construction completion

season for protection of newly created fill areas.

Dune/Swale Area: Dune and Swale habitat shall be planted with a

combination of Bitter Pancium, Marshhay Grass, Sea Oats, and

Gulf Cordgrass. Planting scheme is 8 ft on center of one of the

above plants over 100% of the dune/swale area. There are 681

plants per acre with this planting scheme with 122 acres of

dune/swale habitat being planted.

Plantings in the second year following construction include plantings in

the following areas and described species:

Woody Species: Woody species shall be planted over 15% of the

dune/swale and marsh areas. There are 102 plants per acre with

this planting scheme.

Marsh Area (Initial Restoration Only): Marsh area shall be planted

with Smooth Cordgrass at 8 ft centers over 100% of the marsh area

(50% in TY2 and 50% in TY3).

Plantings in TY3 include plantings in the following areas and described

species:

Marsh Area (Initial Restoration Only): Marsh area shall be planted

with Smooth Cordgrass at 8 ft centers over 100% of the marsh area

(50% in TY2 and 50% in TY3).

[30] Planning, Engineering & Design

PED was assessed at 5.0% of construction cost. Percentage derived from USACE New

Orleans District from graded scale based on project cost.

[31] Construction Management

Construction Management was assessed at 5.0% of construction cost. Percentage derived

from USACE New Orleans District from graded scale based on project cost.


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 1

Description Quantity UOM ContractCost ProjectCost

TBBSR Bid Schedule Summary

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

230,281,715.35 230,281,715.35

90,089,311.71 90,089,311.71

1 Inital Restoration 1.00 EA 90,089,311.71 90,089,311.71

50,000.00 50,000.00

1.1 01 Lands and Damages 1.00 EA 50,000.00 50,000.00

1.1.1 USR 01A Acquisitions / Interagency Donations 1.00 LS 50,000.00 50,000.00

5,821,200.00 5,821,200.00

1.2 06 Fish & Wildlife 1.00 EA 5,821,200.00 5,821,200.00

1,147,600.00 1,147,600.00

1.2.1 USR 06A Adaptive Management Program Setup 1.00 EA 1,147,600.00 1,147,600.00

1,280,000.00 1,280,000.00

1.2.2 USR 06B Adaptive Management Plan Implementation 1.00 EA 1,280,000.00 1,280,000.001.2.3 USR 06C Post Construction Monitoring 1.00 LS 3,393,600.00 3,393,600.00

76,561,919.73 76,561,919.73

1.3 17 Beach Replenishment 1.00 EA 76,561,919.73 76,561,919.73

76,561,919.73 76,561,919.73

1.3.1 02 Beach and Marsh Construction 1.00 EA 76,561,919.73 76,561,919.73

6,347,259.48 6,347,259.48

1.3.1.1 02A Mobilization / Demobilization 1.00 EA 6,347,259.48 6,347,259.48

1.3.1.1.1 USR 02 Dredge Mob / Demob 1.00 LS 847,309.09 847,309.09

24,718.84 24,718.84

1.3.1.1.2 USR 03 Mob/Demob Crew & Equipment 7.80 DAY 192,806.97 192,806.97

151,176.64 151,176.64

1.3.1.1.3 USR 04 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.25

3,251,141.18 3,251,141.18

1.3.1.1.1 01 Pre-layout/Pick-up Pipeline 1.00 EA 3,251,141.18 3,251,141.18

513,450.18 513,450.18

1.3.1.1.1.1 01a Shore Pre-layout/Pick-up Pipeline 1.00 EA 513,450.18 513,450.18

29.56 29.56

1.3.1.1.1.1.1 USR Pre-lay Shore Pipeline 5,656.00 LF 167,163.84 167,163.84

29.56 29.56

1.3.1.1.1.1.2 USR Pickup Shore Pipeline 11,071.00 LF 327,204.90 327,204.90

349.15 349.15

1.3.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 11.31 DAY 3,949.55 3,949.55

683.40 683.40

1.3.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 22.14 DAY 15,131.89 15,131.89

43.52 43.52

1.3.1.1.1.2 01b Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 2,737,691.00 2,737,691.00

1,771,911.04 1,771,911.04

1.3.1.1.1.2.1 Beach/Dune 1.00 EA 1,771,911.04 1,771,911.04


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 2

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

7.61 7.61

1.3.1.1.1.2.1.1 USR Pre-lay Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

7.61 7.61

1.3.1.1.1.2.1.2 USR Pickup Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

9,708.27 9,708.27

1.3.1.1.1.2.1.3 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

9,708.27 9,708.27

1.3.1.1.1.2.1.4 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

28.17 28.17

1.3.1.1.1.2.2 Marsh 34,288.00 LF 965,779.96 965,779.96

7.61 7.61

1.3.1.1.1.2.2.1 USR Pre-lay Submerged Pipeline 34,288.00 LF 260,971.91 260,971.91

7.61 7.61

1.3.1.1.1.2.2.2 USR Pickup Submerged Pipeline 34,288.00 LF 260,971.91 260,971.91

5,291.49 5,291.49

1.3.1.1.1.2.2.3 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 221,918.07 221,918.07

5,291.49 5,291.49

1.3.1.1.1.2.2.4 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 221,918.07 221,918.07

70,214,660.25 70,214,660.25

1.3.1.2 02B Whiskey Island Plan C 1.00 EA 70,214,660.25 70,214,660.25

63,291,395.12 63,291,395.12

1.3.1.2.1 01 Beach/Dune Fill 1.00 EA 63,291,395.12 63,291,395.12

6.97 6.97

1.3.1.2.1.1 USR Beach/Dune Fill 8,330,215.00 CY 58,064,427.87 58,064,427.87

223,915.42 223,915.42

1.3.1.2.1.2 USR Beach/Dune Construction 10.69 MO 2,393,655.86 2,393,655.86

50,526.76 50,526.76

1.3.1.2.1.3 USR Survey Crew - Offshore 10.69 MO 540,131.10 540,131.10

29,937.08 29,937.08

1.3.1.2.1.4 USR Survey Crew - Onshore 10.69 MO 320,027.34 320,027.34

117,558.78 117,558.78

1.3.1.2.1.5 USR Pipeline Crew - Offshore 10.69 MO 1,256,703.32 1,256,703.32

67,020.55 67,020.55

1.3.1.2.1.6 USR Pipeline Crew - Shore 10.69 MO 716,449.64 716,449.64

3,309,212.88 3,309,212.88

1.3.1.2.2 02 Marsh Fill 1.00 EA 3,309,212.88 3,309,212.88

5.05 5.05

1.3.1.2.2.1 USR Marsh Fill 579,724.00 CY 2,930,005.83 2,930,005.83

151,927.55 151,927.55


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 3

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1.3.1.2.2.2 USR Marsh Construction 0.76 MO 115,464.94 115,464.94

490.62 490.62

1.3.1.2.2.3 USR Marsh Grade Stakes 127.00 EA 62,309.31 62,309.31

50,526.76 50,526.76

1.3.1.2.2.4 USR Survey Crew - Offshore 0.76 MO 38,400.34 38,400.34

29,937.08 29,937.08

1.3.1.2.2.5 USR Survey Crew - Onshore 0.76 MO 22,752.18 22,752.18

117,558.78 117,558.78

1.3.1.2.2.6 USR Pipeline Crew - Offshore 0.76 MO 89,344.67 89,344.67

67,020.55 67,020.55

1.3.1.2.2.7 USR Pipeline Crew - Shore 0.76 MO 50,935.62 50,935.62

626,450.00 626,450.00

1.3.1.2.3 03 Access Channel 1.00 EA 626,450.00 626,450.00

85.00 85.00

1.3.1.2.3.1 USR Access Channel 7,370.00 LF 626,450.00 626,450.00

1,327,620.00 1,327,620.00

1.3.1.2.4 04 Containment Dike 1.00 EA 1,327,620.00 1,327,620.00

52.50 52.50

1.3.1.2.4.1 USR Containment Dike 25,288.00 LF 1,327,620.00 1,327,620.00

293,718.75 293,718.75

1.3.1.2.5 05 Sand Fencing 1.00 EA 293,718.75 293,718.75

16.25 16.25

1.3.1.2.5.1 USR Sand Fencing 18,075.00 LF 293,718.75 293,718.75

1,366,263.50 1,366,263.50

1.3.1.2.6 06 Vegetative Plantings 1.00 EA 1,366,263.50 1,366,263.50

779,938.00 779,938.00

1.3.1.2.6.1 06a Plantings - TY1 1.00 EA 779,938.00 779,938.00

1.3.1.2.6.1.1 USR Planting Mob/Demob - TY1 1.00 LS 20,000.00 20,000.00

100.00 100.00

1.3.1.2.6.1.2 USR Aerial Seeding - TY1 122.00 ACR 12,200.00 12,200.00

9.00 9.00

1.3.1.2.6.1.3 USR Dune/Swale Area - TY1 83,082.00 EA 747,738.00 747,738.00

399,650.75 399,650.75

1.3.1.2.6.2 06b Plantings - TY2 1.00 EA 399,650.75 399,650.75

1.3.1.2.6.2.1 USR Planting Mob/Demob - TY2 1.00 LS 20,000.00 20,000.00

9.00 9.00

1.3.1.2.6.2.2 USR Woody Species - TY2 23,664.00 EA 212,976.00 212,976.00

4.45 4.45

1.3.1.2.6.2.3 USR Marsh Area - TY2 37,455.00 EA 166,674.75 166,674.75

186,674.75 186,674.75


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 4

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

1.3.1.2.6.3 06c Plantings - TY3 1.00 EA 186,674.75 186,674.75

1.3.1.2.6.3.1 USR Planting Mob/Demob - TY3 1.00 LS 20,000.00 20,000.00

4.45 4.45

1.3.1.2.6.3.2 USR Marsh Area - TY3 37,455.00 EA 166,674.75 166,674.75

3,828,095.99 3,828,095.99

1.4 30 Planning, Engineering & Design 1.00 EA 3,828,095.99 3,828,095.99

1.4.1 USR PED 1.00 LS 3,828,095.99 3,828,095.99

3,828,095.99 3,828,095.99

1.5 31 Construction Management 1.00 EA 3,828,095.99 3,828,095.99

1.5.1 USR Construction Management 1.00 LS 3,828,095.99 3,828,095.99

78,334,737.78 78,334,737.78

2 Renourishment TY20 1.00 EA 78,334,737.78 78,334,737.78

50,000.00 50,000.00

2.1 01 Lands and Damages 1.00 EA 50,000.00 50,000.00

50,000.00 50,000.00

2.1.1 USR 01A Acquisitions / Interagency Donations 1.00 EA 50,000.00 50,000.00

71,167,943.44 71,167,943.44

2.2 17 Beach Replenishment 1.00 EA 71,167,943.44 71,167,943.44

71,167,943.44 71,167,943.44

2.2.1 02 Beach Construction 1.00 EA 71,167,943.44 71,167,943.44

5,560,200.57 5,560,200.57

2.2.1.1 02A Mobilization / Demobilization 1.00 EA 5,560,200.57 5,560,200.57

2.2.1.1.1 USR 02 Dredge Mob / Demob 1.00 LS 1,026,030.14 1,026,030.14

24,718.84 24,718.84

2.2.1.1.2 USR 03 Mob/Demob Crew & Equipment 7.80 DAY 192,806.97 192,806.97

151,176.64 151,176.64

2.2.1.1.3 USR 04 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.25

2,285,361.22 2,285,361.22

2.2.1.1.1 01 Pre-layout/Pick-up Pipeline 1.00 EA 2,285,361.22 2,285,361.22

513,450.18 513,450.18

2.2.1.1.1.1 01a Shore Pre-layout/Pick-up Pipeline 1.00 EA 513,450.18 513,450.18

29.56 29.56

2.2.1.1.1.1.1 USR Pre-lay Shore Pipeline 5,656.00 LF 167,163.84 167,163.84

29.56 29.56

2.2.1.1.1.1.2 USR Pickup Shore Pipeline 11,071.00 LF 327,204.90 327,204.90

349.15 349.15

2.2.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 11.31 DAY 3,949.55 3,949.55

683.40 683.40

2.2.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 22.14 DAY 15,131.89 15,131.89

28.17 28.17


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 5

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

2.2.1.1.1.2 01b Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 1,771,911.04 1,771,911.04

1,771,911.04 1,771,911.04

2.2.1.1.1.2.1 Beach/Dune 1.00 EA 1,771,911.04 1,771,911.04

7.61 7.61

2.2.1.1.1.2.1.1 USR Pre-lay Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

7.61 7.61

2.2.1.1.1.2.1.2 USR Pickup Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

9,708.27 9,708.27

2.2.1.1.1.2.1.3 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

9,708.27 9,708.27

2.2.1.1.1.2.1.4 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

65,607,742.87 65,607,742.87

2.2.1.2 02B Whiskey Island Renourishment (Plan C) 1.00 EA 65,607,742.87 65,607,742.87

63,291,395.12 63,291,395.12

2.2.1.2.1 01 Beach/Dune Fill Renourishment 1.00 EA 63,291,395.12 63,291,395.12

6.97 6.97

2.2.1.2.1.1 USR Beach/Dune Fill 8,330,215.00 CY 58,064,427.87 58,064,427.87

223,915.42 223,915.42

2.2.1.2.1.2 USR Beach/Dune Construction 10.69 MO 2,393,655.86 2,393,655.86

50,526.76 50,526.76

2.2.1.2.1.3 USR Survey Crew - Offshore 10.69 MO 540,131.10 540,131.10

29,937.08 29,937.08

2.2.1.2.1.4 USR Survey Crew - Onshore 10.69 MO 320,027.34 320,027.34

117,558.78 117,558.78

2.2.1.2.1.5 USR Pipeline Crew - Offshore 10.69 MO 1,256,703.32 1,256,703.32

67,020.55 67,020.55

2.2.1.2.1.6 USR Pipeline Crew - Shore 10.69 MO 716,449.64 716,449.64

170,000.00 170,000.00

2.2.1.2.2 02 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

2.2.1.2.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

940,695.00 940,695.00

2.2.1.2.3 03 Containment Dike Renourishment 1.00 EA 940,695.00 940,695.00

52.50 52.50

2.2.1.2.3.1 USR Containment Dike 17,918.00 LF 940,695.00 940,695.00

293,718.75 293,718.75

2.2.1.2.4 04 Sand Fencing Renourishment 1.00 EA 293,718.75 293,718.75

16.25 16.25

2.2.1.2.4.1 USR Sand Fencing 18,075.00 LF 293,718.75 293,718.75


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 6

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

911,934.00 911,934.00

2.2.1.2.5 05 Vegetative Plantings Renourishment 1.00 EA 911,934.00 911,934.00

779,938.00 779,938.00

2.2.1.2.5.1 05a Plantings - TY21 1.00 EA 779,938.00 779,938.00

2.2.1.2.5.1.1 USR Planting Mob/Demob - TY21 1.00 LS 20,000.00 20,000.00

100.00 100.00

2.2.1.2.5.1.2 USR Aerial Seeding - TY21 122.00 ACR 12,200.00 12,200.00

9.00 9.00

2.2.1.2.5.1.3 USR Dune/Swale Area - TY21 83,082.00 EA 747,738.00 747,738.00

131,996.00 131,996.00

2.2.1.2.5.2 05b Plantings - TY22 1.00 EA 131,996.00 131,996.00

2.2.1.2.5.2.1 USR Planting Mob/Demob - TY22 1.00 LS 20,000.00 20,000.00

9.00 9.00

2.2.1.2.5.2.2 USR Woody Species - TY22 12,444.00 EA 111,996.00 111,996.00

3,558,397.17 3,558,397.17

2.3 30 Planning, Engineering & Design 1.00 EA 3,558,397.17 3,558,397.17

3,558,397.17 3,558,397.17

2.3.1 USR Planning, Engineering & Design (TY20 Renourishment) 1.00 EA 3,558,397.17 3,558,397.17

3,558,397.17 3,558,397.17

2.4 31 Construction Management 1.00 EA 3,558,397.17 3,558,397.17

3,558,397.17 3,558,397.17

2.4.1 USR Construction Management (TY20 Renourishment) 1.00 EA 3,558,397.17 3,558,397.17

61,857,665.86 61,857,665.86

3 Renourishment TY40 1.00 EA 61,857,665.86 61,857,665.86

50,000.00 50,000.00

3.1 01 Lands and Damages 1.00 EA 50,000.00 50,000.00

50,000.00 50,000.00

3.1.1 USR 01A Acquisitions / Interagency Donations 1.00 EA 50,000.00 50,000.00

56,188,787.14 56,188,787.14

3.2 17 Beach Replenishment 1.00 EA 56,188,787.14 56,188,787.14

56,188,787.14 56,188,787.14

3.2.1 02 Beach and Marsh Construction 1.00 EA 56,188,787.14 56,188,787.14

5,560,200.57 5,560,200.57

3.2.1.1 02A Mobilization / Demobilization 1.00 EA 5,560,200.57 5,560,200.57

3.2.1.1.1 USR 02 Dredge Mob / Demob 1.00 LS 1,026,030.14 1,026,030.14

24,718.84 24,718.84

3.2.1.1.2 USR 03 Mob/Demob Crew & Equipment 7.80 DAY 192,806.97 192,806.97

151,176.64 151,176.64

3.2.1.1.3 USR 04 Mob/Demob Pipeline 13.60 DAY 2,056,002.25 2,056,002.25

2,285,361.22 2,285,361.22


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 7

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

3.2.1.1.1 01 Pre-layout/Pick-up Pipeline 1.00 EA 2,285,361.22 2,285,361.22

513,450.18 513,450.18

3.2.1.1.1.1 01a Shore Pre-layout/Pick-up Pipeline 1.00 EA 513,450.18 513,450.18

29.56 29.56

3.2.1.1.1.1.1 USR Pre-lay Shore Pipeline 5,656.00 LF 167,163.84 167,163.84

29.56 29.56

3.2.1.1.1.1.2 USR Pickup Shore Pipeline 11,071.00 LF 327,204.90 327,204.90

349.15 349.15

3.2.1.1.1.1.3 USR Pre-lay 30-inch Shore Pipeline Standby Cost 11.31 DAY 3,949.55 3,949.55

683.40 683.40

3.2.1.1.1.1.4 USR Pick-up 30-inch Shore Pipeline Standby Cost 22.14 DAY 15,131.89 15,131.89

28.17 28.17

3.2.1.1.1.2 01b Submerged Pre-layout/Pick-up Pipeline 62,908.00 LF 1,771,911.04 1,771,911.04

1,771,911.04 1,771,911.04

3.2.1.1.1.2.1 Beach/Dune 1.00 EA 1,771,911.04 1,771,911.04

7.61 7.61

3.2.1.1.1.2.1.1 USR Pre-lay Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

7.61 7.61

3.2.1.1.1.2.1.2 USR Pickup Submerged Pipeline 62,908.00 LF 478,803.69 478,803.69

9,708.27 9,708.27

3.2.1.1.1.2.1.3 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

9,708.27 9,708.27

3.2.1.1.1.2.1.4 USR Pre-layout 30-inch Submerged Pipeline Standby Cost 41.94 DAY 407,151.84 407,151.84

50,628,586.56 50,628,586.56

3.2.1.2 02B Whiskey Island Renourishment (Plan B) 1.00 EA 50,628,586.56 50,628,586.56

48,318,822.56 48,318,822.56

3.2.1.2.1 01 Beach/Dune Fill Renourishment 1.00 EA 48,318,822.56 48,318,822.56

6.97 6.97

3.2.1.2.1.1 USR Beach/Dune Fill 6,359,650.00 CY 44,328,920.53 44,328,920.53

223,915.42 223,915.42

3.2.1.2.1.2 USR Beach/Dune Construction 8.16 MO 1,827,149.84 1,827,149.84

50,526.76 50,526.76

3.2.1.2.1.3 USR Survey Crew - Offshore 8.16 MO 412,298.39 412,298.39

29,937.08 29,937.08

3.2.1.2.1.4 USR Survey Crew - Onshore 8.16 MO 244,286.54 244,286.54

117,558.78 117,558.78

3.2.1.2.1.5 USR Pipeline Crew - Offshore 8.16 MO 959,279.61 959,279.61

67,020.55 67,020.55

3.2.1.2.1.6 USR Pipeline Crew - Shore 8.16 MO 546,887.66 546,887.66


Eff. Date 10/2009 Project : LCA Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction LCATBBSR Bid Schedule Summary Page 8

Description Quantity UOM ContractCost ProjectCost

Labor ID: LB06NATPD EQ ID: EP07R03 Currency in US dollars TRACES MII Version 3.01

170,000.00 170,000.00

3.2.1.2.2 02 Access Channel Renourishment 1.00 EA 170,000.00 170,000.00

85.00 85.00

3.2.1.2.2.1 USR Access Channel 2,000.00 LF 170,000.00 170,000.00

935,655.00 935,655.00

3.2.1.2.3 03 Containment Dike Renourishment 1.00 EA 935,655.00 935,655.00

52.50 52.50

3.2.1.2.3.1 USR Containment Dike 17,822.00 LF 935,655.00 935,655.00

292,175.00 292,175.00

3.2.1.2.4 04 Sand Fencing Renourishment 1.00 EA 292,175.00 292,175.00

16.25 16.25

3.2.1.2.4.1 USR Sand Fencing 17,980.00 LF 292,175.00 292,175.00

911,934.00 911,934.00

3.2.1.2.5 05 Vegetative Plantings Renourishment 1.00 EA 911,934.00 911,934.00

779,938.00 779,938.00

3.2.1.2.5.1 05a Plantings - TY41 1.00 EA 779,938.00 779,938.00

3.2.1.2.5.1.1 USR Planting Mob/Demob - TY41 1.00 LS 20,000.00 20,000.00

100.00 100.00

3.2.1.2.5.1.2 USR Aerial Seeding - TY41 122.00 ACR 12,200.00 12,200.00

9.00 9.00

3.2.1.2.5.1.3 USR Dune/Swale Area - TY41 83,082.00 EA 747,738.00 747,738.00

131,996.00 131,996.00

3.2.1.2.5.2 05b Plantings - TY42 1.00 EA 131,996.00 131,996.00

3.2.1.2.5.2.1 USR Planting Mob/Demob - TY42 1.00 LS 20,000.00 20,000.00

9.00 9.00

3.2.1.2.5.2.2 USR Woody Species - TY42 12,444.00 EA 111,996.00 111,996.00

2,809,439.36 2,809,439.36

3.3 30 Planning, Engineering & Design 1.00 EA 2,809,439.36 2,809,439.36

2,809,439.36 2,809,439.36

3.3.1 USR Planning, Engineering & Design (TY40 Renourishment) 1.00 EA 2,809,439.36 2,809,439.36

2,809,439.36 2,809,439.36

3.4 31 Construction Management 1.00 EA 2,809,439.36 2,809,439.36

2,809,439.36 2,809,439.36

3.4.1 USR Construction Management (TY40 Renourishment) 1.00 EA 2,809,439.36 2,809,439.36


LCA TERREBONNE BASIN

BARRIER SHORELINE

RESTORATION STUDY

ANNEX L-5

RISK ANALYSES FOR THE

INITIAL RESTORATION OF THE

NER PLAN AND FIRST

COMPONENT OF

CONSTRUCTION


Louisiana Coastal Authority

Terrebonne Basin Barrier Shoreline Restoration

Integrated Feasibility Study and

Environmental Impact Statement

Project Cost and Schedule Risk Analysis Report

National Ecosystem Restoration Plan

Prepared for:

U.S. Army Corps of Engineers,

New Orleans District

Prepared by:

SJB Group, LLC. & Coastal Engineering Consultants, Inc.

Under contract from Louisiana Office of Coastal Protection and Restoration

August 2010


i

TABLE OF CONTENTS

EXECUTIVE SUMMARY ........................................................................................ ES-1

1.0 PURPOSE.....................................................................................................................1

2.0 BACKGROUND ..........................................................................................................1

2.1 PARTICIPATING AGENCIES .................................................................................1

2.2 STUDY AUTHORIZATION ....................................................................................1

2.3 STUDY PURPOSE ................................................................................................2

2.4 STUDY LOCATION..............................................................................................2

2.5 NATIONAL ECOSYSTEM RESTORATION PLAN ....................................................3

3.0 REPORT SCOPE.........................................................................................................4

3.1 STUDY SCOPE ...................................................................................................4

3.2 USACE RISK ANALYSIS PROCESS....................................................................5

4.0 METHODOLOGY / PROCESS.................................................................................5

4.1 IDENTIFY POTENTIAL RISK FACTORS................................................................6

4.2 REFINE RISK REGISTER AND ASSIGN RISK LEVELS...........................................6

4.3 DEVELOP FINAL RISK REGISTER AND QUANTIFY RISK FACTORS .....................6

4.3.1 CONTINGENCY RISK FACTORS .............................................................7

4.4 RUN CRYSTAL BALL SIMULATIONS AND ANALYZE CONTINGENCIES .............10

5.0 KEY ASSUMPTIONS...............................................................................................11

6.0 RISK ANALYSIS RESULTS ...................................................................................11

6.1 COST RISK ANALYSIS CONTINGENCY RESULTS ..............................................11

6.2 SCHEDULE RISK ANALYSIS CONTINGENCY RESULTS .....................................13

6.3 SENSITIVITY ANALYSIS RESULTS ...................................................................14

7.0 MAJOR FINDINGS / OBSERVATIONS / RECOMMENDATIONS .................17

7.1 MAJOR FINDINGS / OBSERVATIONS.................................................................17

7.2 RECOMMENDATIONS.......................................................................................23

8.0 REFERENCES...........................................................................................................24


ii

LIST OF TABLES

Table ES-1. NER Plan Cost Summary - Program Year (2012) Project Cost ...............ES-1

Table ES-2. NER Plan Cost Summary - Fully Funded Project Cost............................ES-2

Table 1. Topics and Work Breakdown Structure Analyzed ...............................................6

Table 2. Initial Restoration Project Cost Estimate with Contingencies Summary for

NER Plan Contract No. 1...................................................................................12

Table 3. Initial Restoration Project Cost Estimate with Contingencies Summary - NER

Plan Contract No. 2............................................................................................12

Table 4. Initial Restoration Project Construction Schedule with Contingencies

Summary - NER Plan Contract No. 1 ...............................................................13

Table 5. Initial Restoration Project Construction Schedule with Contingencies

Summary - NER Plan Contract No. 2 ...............................................................13

Table 6. Baseline Construction Cost Comparison Summary for the Initial Restoration

of NER Plan Contract No. 1 ..............................................................................18

Table 7. Baseline Construction Cost Comparison Summary for the Initial Restoration

of NER Plan Contract No. 2 ..............................................................................19

Table 8. Baseline Construction Schedule Comparison Summary for the Initial

Restoration of NER Plan Contract No. 1...........................................................20

Table 9. Baseline Construction Schedule Comparison Summary for the Initial

Restoration of NER Plan Contract No. 2...........................................................21

Table 10. NER Plan Cost Summary - Program Year (2012) Project Cost .......................22

Table 11. NER Plan Cost Summary - Fully Funded Project Cost....................................22

LIST OF FIGURES

Figure 1. Cost Sensitivity Analysis - NER Plan Contract No. 1.......................................15

Figure 2. Cost Sensitivity Analysis - NER Plan Contract No. 2.......................................15

Figure 3. Schedule Sensitivity Analysis - NER Plan Contract No. 1 ...............................16

Figure 4. Schedule Sensitivity Analysis - NER Plan Contract No. 2 ...............................16

LIST OF APPENDICES

Detailed Risk Registers.......................................................................... ATTACHMENT A


ES-1

EXECUTIVE SUMMARY

This report presents a recommendation for the total project cost and schedule

contingencies for initial restoration of the National Ecosystem Restoration (NER) Plan of

the Louisiana Coastal Authority, Terrebonne Basin Barrier Shoreline Restoration Study

in Terrebonne and Lafourche Parishes, Louisiana. The NER Plan includes the initial

restoration of Whiskey Island to a design of Plan C with renourishment events in Target

Year (TY) 20 and 40; Trinity Island to a design of Plan C with renourishment event in

TY25; Raccoon Island to a design of Plan E with Terminal Groin with terminal groin

O&M in TY10 and renourishment in TY30; and Timbalier Island to a design of Plan E

with renourishment in TY30. The renourishment in TY20 and TY40 for Whiskey Island

would be to add a design of Plan C and Plan B, respectively. The renourishment of

Trinity Island in TY25 would be to add a design of Plan C. The renourishment of

Raccoon Island and Timbalier in TY30 would be to restore to a design of Plan B. In

compliance with Engineer Regulation (ER) 1110-2-1302 Civil Works Cost Engineering,

dated September 15, 2008, a formal risk analysis study was conducted for the

development of contingency on the total project cost for the initial restoration and none of

the operation and maintenance construction activities. The purpose of this risk analysis

study was to establish project contingencies by identifying and measuring the cost and

schedule impact of project uncertainties with respect to the estimated project cost for the

initial restoration of the four islands.

The most likely program year (2012) baseline project cost for initial restoration of the

four islands is estimated to be approximately $517.6 Million. Based on the results of the

analysis it is recommended that a contingency and escalation value of approximately

$171.5 Million, or 33.1%, be added to the total project cost for a fully funded cost of

$689.0 Million.

The following tables ES-1 and ES-2 present both the baseline cost and fully funded

project cost, respectively, of the initial restoration component for the NER Plan based on

the anticipated contract. The cost is intended to address the congressional request of

project cost estimates to implement the project. The contingency is based on an 80%

confidence level, as per U.S. Army Corps of Engineers Civil Works guidance.


ES-2

Table ES-1. NER Plan Cost Summary - Program Year (2012)

Initial Restoration Project Cost

LCA TBBSR NER Plan

Total Project Costs

Program

Year Cost Contingency1

Program

Year

Total Cost2

01 Lands & Damages $545,489 $163,647 $709,136

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

10 Breakwaters & Seawalls $1,833,379 $500,239 $2,332,618

17 Beach Replenishment $462,893,681 $129,859,981 $592,753,662

30 Planning, Engineering & Design $23,234,414 $6,594,157 $29,828,571

31 Construction Management $23,236,463 $6,594,739 $29,831,202

Total Project Costs $517,564,626 $143,712,763 $661,276,389

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

Table ES-2. NER Plan Cost Summary

Fully Funded Initial Restoration Project Cost

LCA TBBSR NER Plan

Total Project Costs

Program

Year Cost

Total

Contingencies

&

Escalations1

Fully

Funded

Total2

01 Lands & Damages $545,489 $169,355 $714,844

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

10 Breakwaters & Seawalls $1,833,379 $661,017 $2,494,396

17 Beach Replenishment $462,893,681 $155,985,226 $618,878,907

30 Planning, Engineering & Design $23,234,414 $6,845,778 $30,080,192

31 Construction Management $23,236,463 $7,804,553 $31,041,016

Total Project Costs $517,564,626 $171,465,929 $689,030,555

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

KEY FINDINGS/OBSERVATIONS/RECOMMENDATIONS

The key cost risk drivers identified through sensitivity analysis for the initial restoration

component of the NER Plan Contract No. 1 (Whiskey, Trinity, and Raccoon Islands) are

Internal Risks PED-11 (Geotechnical Issues Beach/Dune - Ship Shoal Borrow Area) in

additional to External Risks PR-2 (Fuel Prices), PR-3 (Severe Weather/Downtime), PR-5

(Long Pipeline to Island for Beach Fill), PR-7 (Bidder’s Risk in Volatile Market), and


ES-3

PR-8 (Pipeline Steel Prices) which together contribute 99.3% of the statistical cost

variance.

The key cost risk drivers identified through sensitivity analysis for the initial restoration

component of the NER Plan Contract No. 2 (Timbalier Island) are Internal Risks PED-11

(Geotechnical Issues Beach/Dune - South Pelto Borrow Area) in additional to External

Risks PR-2 (Fuel Prices), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to

Island for Beach Fill), PR-7 (Bidder’s Risk in Volatile Market), and PR-8 (Pipeline Steel

Prices) which together contribute 99.3% of the statistical cost variance.

The key schedule risk drivers identified through sensitivity analysis for the initial

restoration component of the NER Plan are External Risks PR-1 (Sponsor’s Ability to

Fund its Share), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to Island for

Beach Fill), PR-4 (Delays due to Design Modifications), and PR-10 (Dredge

Acquisition), which together contribute 96.4% and 97.4% of the statistical schedule

variance for Contracts No. 1 and No 2, respectively.

Recommendations, as detailed within the main report, include the implementation of cost

and schedule contingencies, further iterative study of risks throughout the project lifecycle, potential mitigation throughout the Planning, Engineering & Design phase, and

proactive monitoring and control of risk identified in this study.


1

1.0 Purpose

The purpose of this report is to present the findings and results of the Cost and Schedule

Risk Analysis for the Louisiana Coastal Authority, Terrebonne Basin Barrier Shoreline

Restoration Study (LCA TBBSR). The results presented in this report include the

recommended contingencies to be added to the base estimate cost for the initial

restoration component of the National Ecosystem Restoration (NER) Plan. Additionally,

to provide confidence that the actual project execution costs will be within the resulting

estimated budget value. Furthermore, the scope of the report includes the identification

and communication of important steps, logic, key assumptions, limitations, and decisions

to help ensure that risk analysis results can be appropriately interpreted. The results

presented herein are intended to provide project leadership with contingency information

for scheduling, budgeting, and project control purposes, as well as, provide tools to

support decision making and risk management as the project progresses through

Planning, Engineering & Design and project implementation.

2.0 STUDY BACKGROUND

2.1 PARTICIPATING AGENCIES

The responsible lead Federal agency for this study is the U. S. Army Corps of Engineers

(USACE) - Mississippi Valley, New Orleans District. The non-Federal sponsor for the

study is Louisiana Office of Coastal Protection and Restoration.

2.2 STUDY AUTHORIZATION

Title VII of the Water Resources Development Act (WRDA) 2007 authorizes the LCA

ecosystem restoration program. Included within that authority are requirements for

comprehensive coastal restoration planning, program governance, a Science and

Technology Program, a program for the beneficial use of dredged material, feasibility

studies for restoration plans, project modification investigations, and restoration project

construction, in addition to other program elements. This authorization was

recommended by the Chief of Engineer’s Report, dated January 31, 2005.

Under the 2007 WRDA Section 7006, the LCA program has authority for feasibilitylevel reports of six near-term critical restoration features of which includes the LCA

TBBSR Study.


2

2.3 STUDY PURPOSE

The purpose of the proposed action is to address the goal of the 2004 LCA Plan;

specifically, to address the critical near-term needs for shoreline restoration in

Terrebonne Basin through simulation of historical conditions, which will be achieved by

enlarging the existing barrier islands (width and dune crest) and reducing the current

number of breaches. Additional objectives include analyzing the current conditions of

the barrier islands, assessing impacts from the hurricanes of 2005 and 2008, and

reaffirming the validity of the findings of the Final Environmental Impact Statement. The

Integrated Feasibility Study and Environmental Impact Statement is based on a thorough

review of existing scientific and engineering reports, as well as geospatial, survey, and

geotechnical data.

2.4 STUDY LOCATION

The LCA TBBSR, located in LCA Subprovince 3, provides for the restoration of the

Timbalier and Isles Dernieres barrier island reaches located in Terrebonne and Lafourche

Parishes, Louisiana. The Study area is located in the 3rd Congressional District.

The Isles Dernieres Reach

The Isles Dernieres reach represents a barrier island arc approximately 22 miles long in

Terrebonne Parish and extends from Caillou Bay east to Cat Island Pass. Raccoon Island,

Whiskey Island, Trinity Island, East Island, and Wine Island, the primary islands that

comprise the Isles Dernieres barrier island chain, are backed by Bay Blanc, Bay Round,

Caillou Bay, and Terrebonne Bay, and bordered by the Gulf of Mexico on the seaward

side. The islands range from approximately 0.1 to 1.2 miles wide and are generally

composed of a thin sand cap over a thick mud platform. Elevations are generally low and

the islands are frequently over washed.

The Isles Dernieres have been and continue to be an important commercial and

recreational resource for Louisiana and the nation for more than 150 years. The islands

support habitats that are critical to the State’s commercial fishing industry. Furthermore,

the mineral-rich subsurface of the island range supports a high concentration of active oil

and gas wells.

The first major coastal resort in Louisiana was located here and was washed away by the

great hurricane of 1856. The Isles Dernieres have also been the location of five Coastal

Wetland Planning, Protection, and Restoration Act projects. These projects included:


3

Raccoon Island (TE-29), Whiskey Island (TE-27), Trinity Island (TE-24), East Island

(TE-20), and New Cut (TE-37).

The Timbalier Islands Reach

The Timbalier Islands reach is comprised of Timbalier Island and East Timbalier Island.

The two islands are on the western edge of the Lafourche barrier shoreline and are

located about 60 miles southwest of New Orleans, Louisiana. This barrier island

shoreline is approximately 20 miles long and backed by Terrebonne and Timbalier Bay to

the north and delimited by Raccoon Pass to the east and Cat Island Pass to the west. The

islands range from 0.1 to 0.6 miles wide and have low elevations. The Timbalier Islands

support onshore and offshore oil and gas development and production. Oil and gas

production facilities are prevalent along East Timbalier Island, while only a few scattered

facilities are present along Timbalier Island.

2.5 NATIONAL ECOSYSTEM RESTORATION PLAN

The NER Plan restores the geomorphologic form and ecologic function of the four

islands in the Terrebonne Basin barrier system. Immediately after construction (TY1),

the NER Plan will add 3,283 acres of habitat (dune, intertidal, and supratidal) to the

existing island footprints of Raccoon, Whiskey, Trinity, and Timbalier Islands, increasing

the total size of the islands to 5,840 acres. This includes approximately 472 acres of

dune, 4,320 acres of supratidal habitat, and 1,048 acres of intertidal habitat. Raccoon

Island will be renourished at TY30 by adding adequate sediment such that the dune and

supratidal beach acres would be equivalent to that of a newly constructed Plan B

template. Whiskey Island will require two renourishment intervals. The first will occur

at TY20 and will include the addition of the same amount of dune and supratidal beach

habitat that was originally created in TY1. The second renourishment interval will occur

at TY40 and will include the addition of the same amount of dune and supratidal beach

habitat needed to construct a Plan B template. Trinity Island will be renourished at TY25

by adding the same amount of dune and supratidal beach habitat that was originally

added in TY1. Timbalier Island will be renourished at TY30 by adding adequate

sediment such that the dune and supratidal beach habitat acres would be equivalent to the

acres of a newly constructed Plan B template. The renourishment events were not

evaluated in this risk analysis.

The barrier island restoration features of the initial restoration would achieve the planning

objectives by maximizing the barrier island’s ability to provide geomorphic and

hydrologic form and ecological function, as well as, improve critical barrier island

habitats for fish, migratory birds, and other terrestrial and aquatic species. Sediment

would be placed into the system to supplement long-shore sediment transport processes


4

along the gulf shoreline by mechanically introducing compatible sediment, and

increasing the ability of the restored area to continue to function and provide habitat with

minimum continuing intervention.

The NER Plan is the best and meets the goal of the 2004 LCA Plan to address critical

near-term needs for shoreline restoration for Terrebonne Basin through simulating

historical conditions by enlarging the barrier islands (width and dune crest) and reducing

the current number of breaches to ensure the continuing geomorphic and ecological form

and function of the barrier islands. The selection of the NER Plan was based on a

thorough review of existing scientific and engineering reports, as well as geospatial,

survey, and geotechnical data which reaffirmed that the findings of the Final

Environmental Impact Statement remained valid.

The NER Plan is also the plan that best meets the USACE Principles and Guidelines of

completeness, effectiveness, efficiency, and acceptability, as well as the Environmental

Operating Principles of environmental sustainability, interdependence, balance and

synergy, accountability, knowledge, respect, and assessing and mitigating cumulative

impacts.

3.0 REPORT SCOPE

3.1 PROJECT SCOPE

Engineering Circular Bulletin (ECB) 2007-17, Application of Cost Risk Analysis

Methods to Develop Contingencies for Civil Works Total Project Costs (Sept. 10, 2007)

requires that a formal risk analysis be prepared for all decision documents requiring

Congressional authorization whose total costs are in excess of forty million dollars.

In addition to broadly defined risk analysis standards and recommended practices, a risk

analysis is to be performed to meet the requirements and recommendations of the

following documents and sources:

Cost and Schedule Risk Analysis Process guidance prepared by the USACE Cost

Engineering Directory of Expertise for Civil Works (Cost Engineering Dx), dated

May 17, 2009.

Engineer Regulation (ER) 1110-2-1302 Civil Works Cost Engineering, dated

Sept. 15, 2008.

Engineer Technical Letter (ETL) 1110-2-573 Construction Cost Estimating Guide

for Civil Works, dated Sept. 30, 2008.


5

3.2 USACE RISK ANALYSIS PROCESS

A risk analysis is performed to determine the probability of various cost and schedule

variances that could affect the total project cost. The analyses of the cost risk factors

associated with the project will determine the required contingency needed in the cost

estimate to achieve any desired level of cost confidence. A similar analysis is also used

to determine the probability of various project schedule duration impacts and then

quantify the required schedule contingency needed in the schedule to achieve any desired

level of schedule confidence. Together the contingency for both cost and schedule will

provide a total project cost and schedule at the desired confidence level.

The risk analysis process uses Monte Carlo techniques to determine probabilities and

contingency. The Monte Carlo techniques are facilitated computationally by a

commercially available risk analysis software package (Crystal Ball) that is an add-in to

Microsoft Excel. The software determines contingency amounts based on specific

‘confidence levels’. These confidence levels express the probability that the

corresponding contingency amount will cover the cost of the project being studied.

In general, the amount of contingency included in project control plans depends on the

project leadership’s willingness to accept risk of project overruns. The less risk that

project leadership is willing to accept, the more contingency that should be applied in the

project control plans. This risk of overrun is expressed by Crystal Ball in a probabilistic

context using confidence levels. The Cost Engineering Dx guidance for cost and schedule

risk analysis focuses on risk and opportunity potential, all project features, internal and

external risks to the project. The Cost Engineering Dx recommends budget presentation

with a contingency value at the eighty-percent level of confidence (80%) for successful

project execution within the established budget. This 80% confidence level is the

standard normally provided to Congress by USACE and other Government agencies.

4.0 METHODOLOGY / PROCESS

A risk analysis begins with the identification of risk factors for the restoration. The risk

identification process includes the major PDT members knowledgeable with the potential

impacts. The risks are then compared for commonalities with other risk factors and a

preliminary risk register is developed for risk level assignment. Following risk level

evaluation and assignment, those risk factor found to have 'moderate' or 'high' impact

risks are carried forward to the final risk register and quantified. The final risk register

serves as the risk models used within the Crystal Ball software. These primary steps of

the risk analysis process, in functional terms, are described in the following subsections.


6

4.1 IDENTIFY POTENTIAL RISK FACTORS

The risk analysis process began with a brainstorming session to identify any and all

potential risk factors associated with the project. These potential risks were then

evaluated to determine if correlations existed between any of the potential risk factors.

Risk factors that were determined to have correlations were analyzed to determine the

nature of the correlation. If strong correlations existed then the factors were combined

into a single risk factor. If correlations were determined wherein the risk factors had

similarities but contained inherent differences, the factors were revised and/or additional

risk factors were added such that all risks could be evaluated individually.

The risks developed and refined during the brainstorming sessions were transferred into a

risk register template in Microsoft Excel as the Initial Risk Register (ATTACHMENT

A).

4.2 REFINE RISK REGISTER AND ASSIGN RISK LEVELS

The initial risk register was structured such that elements of risk were assigned under a

topic and feature code and given a risk factor number allowing traceability throughout the

process. Similar to the identification and assessment process, risk factor quantification

involved the evaluation of the impact of the risk on the project. The risk factors were

assigned a likelihood of occurrence and a level of impact the risk would have on the

project cost or schedule. Table 1 provides a listing of the topics and feature codes

evaluated in this risk assessment.

Table 1. Topics and Work Breakdown Structure Analyzed

PPM Project and Program Management

01 Lands and Damages

06 Fish & Wildlife (Adaptive Management Plan)

10 Breakwaters & Seawalls

17 Beach Replenishment

30 Planning, Engineering & Design

31 Construction Management

PR Programmatic Risks

4.3 DEVELOP FINAL RISK REGISTER AND QUANTIFY RISK FACTORS

Those risk factors determined to have a 'moderate' or 'high' impact on the project cost or

schedule were carried forward to the final risk register and quantified.


7

The quantification process involved collaboration between the ATR review lead, District

cost engineers, and the A/E cost estimators. This process used an iterative approach to

estimate the following elements of each risk factor:

Maximum possible value for the risk factor (high value, worst-case)

Minimum possible value for the risk factor (low value, best-case)

Most likely value (the original estimate value, if applicable)

Nature of the probability density function used to approximate risk factor

uncertainty

Correlations between risk factors

Affected cost and/or schedule elements

Information was extracted from the cost estimates and placed into the final cost risk

register for cost risk analysis purposes (Attachment A). For the schedule risk analysis, the

durations for each risk (if applicable) were placed into a final schedule risk register

(Attachment A).

4.3.1 Contingency Risk Factors

The following are those elements analyzed in the cost and schedule risk models to

determine the appropriate contingencies.

4.3.1.1 Beach/Dune and Marsh Fill Design Quantities (Cost & Schedule)

The island design was developed utilizing survey data collected in 2006 as part of the

Louisiana Barrier Island Comprehensive Monitoring Program (UNO and USGS, 2009).

Through the use of shoreline erosion and landloss rates in the above referenced program,

the fill volumes required in 2012 for beach/dune and marsh were calculated. A risk

variance of +/-10% of the required volume was used to evaluate the risk associated with a

decrease or increase in the erosional effects experienced by the island during this six year

period in addition to a storm event proceeding or during construction. The variances in

beach/dune and marsh required volumes were analyzed as separate risk elements so as to

assess the risk if the beach/dune and marsh fill template experience differing erosional

influences.

4.3.1.2 Geotechnical Issues with the Beach/Dune and Marsh Fill Borrow Areas

(Cost and Schedule)

The sediment characteristics of the proposed borrow areas for beach/dune and marsh

construction were analyzed from data collected within these borrow sources as part of


8

designs for other restoration projects. Projected dredge-to-fill ratios were established and

used in the production estimates for the dredge during construction of the beach/dune and

marsh fill templates. To quantify variances induced by differing sediment characteristics

that could be experienced within the borrow areas proposed for beach/dune fill and the

marsh fill, differing ratios better than and worse than the most likely dredge-to-fill were

evaluated for their affect on the construction cost. Sediment characteristics are one of

three driving forces in determining production rates for the dredging equipment.

4.3.1.3 Sponsor's Ability to Fund Its Share (Schedule)

A delay of eighteen months in the procurement of funds to begin construction of the

project was evaluated. The low risk was assumed to be the same as the most likely

schedule for construction. The high risk was analyzed as a delay for the beginning of

construction.

4.3.1.4 Fuel Prices (Cost)

Overall affects of fuel prices on construction cost were analyzed. The most likely fuel

price was derived from an average of fuel prices for 2009. A lower risk assumes the

price of fuel would fall by as much as 25% from the 2009 average. A higher risk

assumes that a volatile market could increase fuel prices by as much as 60% above the

2009 average price.

4.3.1.5 Severe Weather Downtime (Cost & Schedule)

The effects of dredging material in the open Gulf of Mexico on the dredge's effective

operational hours per day were evaluated. A dredge may experience higher average

operational time per day during periods of favorable weather and conversely experience

lower than average operational time during periods of increases sea state such as during

winter months. The most likely, worst case, and best case operational time per day were

established by review of USACE prior dredging projects. Operational time of the

dredging equipment is one of three driving forces in determining production rates for the

dredging equipment.

4.3.1.6 Delays due to Design Modifications (Schedule)

Following pre-construction surveys of the fill templates, design modification may be

required to adjust the fill templates to maximize effectiveness of the island restoration.

Through prior restoration project experience of the design team, a two month delay in

beginning construction was considered as the high risk variance for the project schedule.


9

4.3.1.7 Long Pipeline to Island for Beach/Dune Fill (Cost & Schedule)

In development of the dredging production rates, it was determined that it was feasible to

construct the beach/dune fill template using as few as two boosters from the borrow area

to the fill template. The most likely number of boosters the contractor would use is three

to maintain higher production rates. The number of booster pumps utilized in the

delivery of sediment to the fill template is one of three driving forces in determining the

production rates for the dredging equipment. Construction cost and schedule variances

were calculated to evaluate the affects on project cost and schedule if the contractor chose

to utilize only two booster pumps during the construction of the beach/dune fill template.

4.3.1.8 Bidder's Risk in a Volatile Market (Cost)

The affects on construction cost of based on the risk assumed by the contractor were

analyzed. These risks are those carried by the contractors that are not analyzed in other

risk elements of this model. Those risks analyzed elsewhere include fuel prices, pipeline

steel prices, weather delays, dredge acquisition, and additional mobilizations due to

hurricanes. Examples of volatile market risk include, but are not limited to, other

projects out for bid requiring the contractor's resources, labor force prices, and

construction equipment availability. A low risk assumes the contractor is eager for the

contract and would bid 10% less than the most likely and conversely a high risk indicates

the contractor may be over extending his resources and submits a bid 25% higher than the

most likely construction cost.

4.3.1.9 Pipeline Steel Prices (Cost)

The risk associated with the changing price per pound of steel was analyzed to determine

it's affect on the cost of the sediment delivery pipeline. Utilizing pricing from prior

USACE projects, the assumed current cost per pound for steel was set a $0.60, the low

price at $0.45, and the high price at $1.50. These prices were used in the determination

of unit cost variances for beach/dune and marsh fill.

4.3.1.10 Dredge Acquisition (Schedule)

The risk associated with the availability of dredges for restoration construction at the time

of notice to proceed for the contractor was considered. The delay to the construction

schedule, while awaiting a dredge to become available from another project, was

determined to be 6 months.


10

4.3.1.11 Hurricane Demobilization/Re-mobilization (Cost & Schedule)

For the possibility of a hurricane affecting the project during construction, an additional

demobilization/re-mobilization of the crew, equipment, and dredge to safe harbor was

evaluated.

4.4 RUN CRYSTAL BALL SIMULATIONS AND ANALYZE CONTINGENCIES

Once the risk factors were refined into the final risk resisters for cost and schedule, the

final quantitative impacts of risk factors served as the risk model and were analyzed using

a combination of professional judgment, empirical data and analytical techniques. The

software uses the most likely, low, and high values for various risks. The most likely

value is usually the value used in the cost estimate. The low and high values, or best-case

and worst-case values, are quantified based off a number of factors, including, but not

limited to, the cost estimate. The software uses these values in conjunction with the

associated probability distribution assigned to each risk to run its Monte Carlo

simulations. Once the software has finished its simulation the total cost of the project

with contingency is forecast for specific confidence levels. The resulting 80% confidence

level contingency amount is the difference between the 80% cost forecast and the base

cost estimate. For schedule contingency analysis, the contingency was calculated as the

difference between the 80% level duration forecast and the base schedule duration,

shown in months. These new durations suggested by the 80% confidence level were then

incorporated into the escalation calculation, i.e., the escalation of the baseline estimate of

cost in the Total Project Cost Summary (TPCS) of the initial restoration of the NER Plan.

The forecasts for cost and/or schedule risk can then be analyzed to determine the

recommended level of contingency for the project. As stated earlier, the contingencies

suggested by the higher confidence levels will account for more risk in the project;

conversely, the amounts suggested by the lower confidence levels could possible leave

the project without sufficient funding if some events do not go as planned.


11

5.0 KEY ASSUMPTIONS

Key assumptions are those that are most likely to affect the determinations and/or

estimates of risk presented in the risk analysis. The key assumptions are important to help

ensure that project leadership and other decision makers understand the steps, logic,

limitations, and decisions made in the risk analysis, as well as any resultant limitations on

the use of outcomes and results. For this project, the assumptions include:

1. Level of Design: The cost comparisons and risk analyses performed and reflected

within this report are based upon design scope and estimates that are considered

to be well developed and designed.

2. Design Scope: The prescribed scope satisfies the requirements of this acquisition.

3. Operation and Maintenance: Operation and maintenance activities were not

included in the cost estimate or schedules, because none were planned for the

selected alternative.

4. Contract Acquisition Strategy: Consistent with cost estimate and schedule

assumptions, it is assumed that the contract acquisition strategy is firm fixed

price.

5. Confidence Levels: The Wall Walla Cost Engineering Dx guidance generally

focuses on the eighty-percent level of confidence (80%) for cost contingency

calculation. For this risk analysis, the eighty-percent level of confidence (80%)

was used. It should be noted that the use of 80% as a decision criteria is a

moderately risk averse approach, generally resulting in higher cost contingencies.

However, the 80% level of confidence also assumes a small degree of risk that the

recommended contingencies may be inadequate to completely capture actual

project costs.

6.0 RISK ANALYSIS RESULTS

The cost and schedule risk analysis results are provided in the following sections. In

addition to contingency calculation results, sensitivity analyses are presented to provide

decision makers with an understanding of variability and the key contributors to the cause

of this variability.

6.1 COST RISK ANALYSIS CONTINGENCY RESULTS

The construction cost contingencies calculated for the 80% confidence level and rounded

to the nearest thousand are shown in Table 2 for Contract No. 1 and Table 3 for Contract

No. 2. The construction cost contingencies for the 50% and 100% confidence levels are

also provided for illustrative purposes.


12

The MII cost estimate produced by USACE-MVN Cost Engineering and A/E cost

estimators with review by the ATR review lead provide initial construction costs of

$505.2 Million for the initial restoration with a price level of the estimate in the 1st

quarter 2010. At the 80% confidence level, the base estimate construction cost

contingency was quantified as approximately $141.7 Million, with a baseline cost of

$646.9 Million.

Table 2. Initial Restoration Project Cost Estimate with Contingencies Summary for

NER Plan Contract No. 1 (Whiskey, Trinity, and Raccoon Islands)

Contingency Level

Mii Cost

Estimate

($1,000)

Contingency

Percentage

Total

Contingency

($1,000) 1

Baseline Cost

Estimate

($1,000) 2

50% Confidence Level -

Initial Restoration

Project Cost

$260,137 17.9% $46,650 $306,787

80% Confidence Level -

Initial Restoration

Project Cost

$260,137 27.4% $71,156 $331,293

100% Confidence Level -

Initial Restoration

Project Cost

$260,137 60.3% $156,892 $417,029

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from Risk Analysis Forecast

Table 3. Initial Restoration Project Cost Estimate with Contingencies Summary for

NER Plan Contract No. 2 (Timbalier Island)

Contingency Level

Mii Cost

Estimate

($1,000)

Contingency

Percentage

Total

Contingency

($1,000) 1

Baseline Cost

Estimate

($1,000) 2

50% Confidence Level -

Initial Restoration

Project Cost

$245,063 19.3% $47,193 $292,256

80% Confidence Level -

Initial Restoration

Project Cost

$245,063 29.4% $71,914 $316,977

100% Confidence Level -

Initial Restoration

Project Cost

$245,063 66.0% $161,831 $406,894

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from Risk Analysis Forecast


13

6.2 SCHEDULE RISK ANALYSIS CONTINGENCY RESULTS

The original estimate of PED and construction duration for the initial restoration in

Contract No.1 is 64.5 months and Contract No. 2 is 55.8 months. At the 80% confidence

level, the projected duration for construction for Contract No. 1 is 93.5 months – an

increase of 45%. Similarly, for Contract No. 2 the 80% confidence level of the projected

duration of construction is 82.9 months - an increase of 48%. The schedule contingency

was calculated by applying the moderate and high level schedule risks identified in the

risk register for each option to the durations of critical path and near critical path tasks.

Table 4. Initial Restoration Project Construction Schedule

with Contingencies Summary for NER Plan Contract No. 1

Risk Analysis Forecast Forecast

Schedule

Total

Contingency

Crystal Ball

Forecast

Schedule

50% Confidence Level -

Initial Restoration

Project Duration

64.5 months 35% 86.9 months

80% Confidence LevelInitial Restoration

Project Duration

64.5 months 45% 93.5 months

100% Confidence Level -

Initial Restoration

Project Duration

64.5 months 75% 113.1 months

Table 5. Initial Restoration Project Construction Schedule

with Contingencies Summary for NER Plan Contract No. 2

Risk Analysis Forecast Forecast

Schedule

Total

Contingency

Crystal Ball

Forecast

Schedule

50% Confidence Level -

Initial Restoration

Project Duration

55.8 months 37% 76.6 months

80% Confidence LevelInitial Restoration

Project Duration

55.8 months 48% 82.9 months

100% Confidence Level -

Initial Restoration

Project Duration

55.8 months 84% 102.5 months


14

6.3 SENSITIVITY ANALYSIS RESULTS

Sensitivity analysis ranks the relative impact of each risk/opportunity as a percentage of

total cost uncertainty. The Crystal Ball software uses a statistical measure (contribution to

variance) that approximates the impact of each risk or opportunity contributing to

variability of cost outcomes during the Monte Carlo simulations.

The risks or opportunities that are considered as key drivers are ranked in the order of

significance to the total project costs variances. Risks are shown with a positive sign to

reflect the potential to increase project cost. Opportunities that have a potential to reduce

project cost and are shown with a negative sign. A longer bar in the sensitivity analysis

chart indicates the risk has a greater potential impact to total project cost.

Figures 1 and 2 presents the sensitivity analyses for cost growth for those risks identified

in the risk register as having a moderate to high level of impact. Similarly, Figures 3 and

4 present the sensitivity analyses for schedule growth risk.

The key cost risk drivers identified through sensitivity analysis for the initial restoration

component of the NER Plan Contract No. 1 (Whiskey, Trinity, and Raccoon Islands) are

Internal Risks PED-11 (Geotechnical Issues Beach/Dune - Ship Shoal Borrow Area) in

additional to External Risks PR-2 (Fuel Prices), PR-3 (Severe Weather/Downtime), PR-5

(Long Pipeline to Island for Beach Fill), PR-7 (Bidder’s Risk in Volatile Market), and

PR-8 (Pipeline Steel Prices) which together contribute 99.3% of the statistical cost

variance.

The key cost risk drivers identified through sensitivity analysis for the initial restoration

component of the NER Plan Contract No. 2 (Timbalier Island) are Internal Risks PED-11

(Geotechnical Issues Beach/Dune - South Pelto Borrow Area) in additional to External

Risks PR-2 (Fuel Prices), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to

Island for Beach Fill), PR-7 (Bidder’s Risk in Volatile Market), and PR-8 (Pipeline Steel

Prices) which together contribute 99.3% of the statistical cost variance.

The key schedule risk drivers identified through sensitivity analysis for the initial

restoration component of the NER Plan are External Risks PR-1 (Sponsor’s Ability to

Fund its Share), PR-3 (Severe Weather/Downtime), PR-5 (Long Pipeline to Island for

Beach Fill), PR-4 (Delays due to Design Modifications), and PR-10 (Dredge

Acquisition), which together contribute 96.4% and 97.4% of the statistical schedule

variance for Contracts No. 1 and No 2, respectively.


15

Figure 1. Cost Sensitivity Analysis - NER Plan Contract No. 1

(Whiskey, Trinity, Raccoon Islands)

Figure 2. Cost Sensitivity Analysis - NER Plan Contract No. 2

(Timbalier Island)


16

Figure 3. Schedule Sensitivity Analysis - NER Plan Contract No. 1

(Whiskey, Trinity, Raccoon Islands)

Figure 4. Schedule Sensitivity Analysis - NER Plan Contract No. 2

(Timbalier Island)


17

Recommendations, as detailed within the main report, include the implementation of cost

and schedule contingencies, further iterative study of risks throughout the project lifecycle, potential mitigation throughout the Planning, Engineering & Design phase, and

proactive monitoring and control of risk identified in this study.

7. 0 MAJOR FINDINGS / OBSERVATIONS / RECOMMENDATION

This section provides a summary of the significant risk analysis results that were

identified in the preceding sections of the report. Risk analysis results are intended to

provide project leadership with contingency information for scheduling, budgeting, and

project control purposes, as well as to provide tools to support decision making and risk

management as projects progress through planning and implementation. Because of the

potential for use of risk analysis results for such diverse purposes, this section also

reiterates and highlights important steps, logic, key assumptions, limitations, and

decisions to help ensure that the risk analysis results are appropriately interpreted.

7.1 MAJOR FINDINGS / OBSERVATIONS

The total construction cost and schedule comparison summaries from Crystal Ball are

provided in Tables 5 and 6, respectively. Additional major findings and observations of

the risk analysis are listed below.

1. Base cost contingency recommended for the initial restoration of the NER Plan in

Contract No. 1 is approximately $69.7 Million, for a total Contract No. 1 cost of

approximately $329.8 Million. Base cost contingency recommended for the initial

restoration of the NER Plan in Contract No. 2 is approximately $72.1 Million, for

a total Contract No. 2 cost of approximately $317.1 Million. The combined total

cost for the NER Plan initial restoration is $646.9 Million These figures are

derived from the TPCS with contingencies calculated by Crystal Ball (Tables 6

and 7). It should be noted that the contingency cost and base cost calculated by

the TPCS are slightly lower than that of Crystal Ball because the cost contingency

and escalation are inclusive in the program cost provided by the Adaptive

Management Plan development team and therefore not applied in the TPCS.

2. Schedule duration contingency recommended for the initial restoration of the

NER Plan in Contract No. 1 is 29 months, for a total duration of 93.5 months for

this contract. Schedule duration contingency recommended for the initial

restoration of the NER Plan in Contract No. 2 is 27.1 months, for a total duration

of 82.9 months for this contract. The monthly duration contingencies are


18

reflective of the 80% confidence level values calculated by Crystal Ball (Table 8

and 9).

3. As shown in Figures 1 through 4, the cost risk and schedule risk for initial

restoration of the NER Plan are mostly dependent on two risk factors each.

4. Operation and maintenance activities were not included in the presented cost

estimate or schedules. Therefore, a full lifecycle risk analysis could not be

performed. Risk analysis results or conclusions could be significantly different if

operation and maintenance activities were included.

Table 6. Baseline Construction Cost Comparison Summary for the Initial

Restoration of the NER Plan Contract No. 1

Forecast:

TOTAL

PROJECT

COST

Percentile Forecast

values

0% $214,615,435

5% $263,758,287

10% $272,321,941

15% $278,579,778

20% $283,578,321

25% $287,986,952

30% $292,113,720

35% $295,970,432

40% $299,616,675

45% $303,187,426

50% $306,787,355

55% $310,347,522

60% $314,014,886

65% $317,876,733

70% $322,008,589

75% $326,376,077

80% $331,293,014

85% $337,070,819

90% $344,246,778

95% $354,951,791

100% $417,028,799

Minimum $214,615,435

Maximum $417,028,799

80% Confidence Level: $331,293,014

Original Project Cost: $260,137,358

Total Contingency Based on 80% 27.4%


19

Confidence:

Table 7. Baseline Construction Cost Comparison Summary for the Initial

Restoration of the NER Plan Contract No. 2

Forecast:

TOTAL

PROJECT

COST

Percentile Forecast

values

0% $190,536,325

5% $248,620,024

10% $257,548,301

15% $263,775,469

20% $268,883,315

25% $273,386,225

30% $277,368,117

35% $281,291,544

40% $285,029,931

45% $288,595,226

50% $292,255,790

55% $295,876,247

60% $299,641,907

65% $303,483,364

70% $307,543,774

75% $312,038,011

80% $316,976,563

85% $322,828,115

90% $330,114,325

95% $340,616,898

100% $406,894,479

Minimum $190,536,325

Maximum $406,894,479

80% Confidence Level: $316,976,563

Original Project Cost: $245,062,710

Total Contingency Based on 80%

Confidence: 29.4%


20

Table 8. Baseline Construction Schedule Comparison Summary for the Initial

Restoration of the NER Plan Contract No. 1

Forecast:

TOTAL

PROJECT

SCHEDULE

Percentile Forecast

values

0% 61.21

5% 74.81

10% 77.24

15% 78.99

20% 80.43

25% 81.71

30% 82.87

35% 83.93

40% 84.95

45% 85.96

50% 86.92

55% 87.91

60% 88.92

65% 89.94

70% 91.04

75% 92.21

80% 93.50

85% 94.92

90% 96.72

95% 99.29

100% 113.14

Minimum 61.21

Maximum 113.14

80% Confidence Level: 93.50

Original Project Cost: 64.51

Total Contingency Based on 80%

Confidence: 44.9%


21

Table 9. Baseline Construction Schedule Comparison Summary for the Initial

Restoration of the NER Plan Contract No. 2

Forecast:

TOTAL

PROJECT

SCHEDULE

Percentile Forecast

values

0% 52.54

5% 64.88

10% 67.19

15% 68.85

20% 70.23

25% 71.44

30% 72.54

35% 73.62

40% 74.61

45% 75.60

50% 76.58

55% 77.55

60% 78.52

65% 79.54

70% 80.57

75% 81.66

80% 82.85

85% 84.26

90% 85.92

95% 88.28

100% 102.53

Minimum 52.54

Maximum 102.53

80% Confidence Level: 82.85

Original Project Cost: 55.82

Total Contingency Based on 80%

Confidence: 48.4%


22

Through utilization of the TPCS, the base cost estimate for the initial restoration from the

MII escalated to the project year of the 1st quarter 2012 equals approximately $517.6

Million. Adding the cost and schedule influence contingencies provides a project cost of

approximately $661.3 Million. A breakdown of the program year cost by work feature is

presented in Table 10.

Table 10. NER Plan Cost Summary - Program Year (2012)

Initial Restoration Project Cost

LCA TBBSR NER Plan

Total Project Costs

Program

Year Cost2 Contingency1

Program

Year Total

Cost2

01 Lands & Damages $545,489 $163,647 $709,136

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

10 Breakwaters & Seawalls $1,833,379 $500,239 $2,332,618

17 Beach Replenishment $462,893,681 $129,859,981 $592,753,662

30 Planning, Engineering & Design $23,234,414 $6,594,157 $29,828,571

31 Construction Management $23,236,463 $6,594,739 $29,831,202

Total Project Costs $517,564,626 $143,712,763 $661,276,389

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

Expanding on the program year cost estimate, escalation to midpoint of work features can

be calculated. The results provide a fully funded project cost of approximately $689.0

Million. A breakdown of the fully funded project cast is presented in Table 11.

Table 11. NER Plan Cost Summary - Fully Funded Initial Restoration Project Cost

LCA TBBSR NER Plan

Total Project Costs

Program

Year Cost2

All

Contingencie

s &

Escalations1

Fully

Funded

Total2

01 Lands & Damages $545,489 $169,355 $714,844

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

10 Breakwaters & Seawalls $1,833,379 $661,017 $2,494,396

17 Beach Replenishment $462,893,681 $155,985,226 $618,878,907

30 Planning, Engineering & Design $23,234,414 $6,845,778 $30,080,192

31 Construction Management $23,236,463 $7,804,553 $31,041,016

Total Project Costs $517,564,626 $171,465,929 $689,030,555

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS


23

7.2 RECOMMENDATIONS

Risk Management is an all-encompassing, iterative, and life-cycle process of project

management. The Project Management Institute’s (PMI) A Guide to the Project

Management Body of Knowledge (PMBOK® Guide), 4th edition, states that “project

risk management includes the processes concerned with conducting risk management

planning, identification, analysis, responses, and monitoring and control on a project.”

Risk identification and analysis are processes within the knowledge area of risk

management. Its outputs pertinent to this effort include the risk register, risk

quantification (risk analysis model), contingency report, and the sensitivity analysis.

The intended use of these outputs is implementation by the project leadership with

respect to risk responses (such as mitigation) and risk monitoring and control. In short,

the effectiveness of the project risk management effort requires that the proactive

management of risks not conclude with the study completed in this report.

This section provides a list of recommendations for continued management of the risks

identified and analyzed in this study. (Note: this list is not all-inclusive)

1. Cost Estimate Quality: The cost estimate was developed for the restoration of

Whiskey Island based on feasibility level surveys and designs. Risks associated

with the information utilized in the designs have been analyzed within this risk

assessment. It is recommended that the project leadership, restoration design

team, and project cost estimators work closely in re-evaluating the project cost

elements and associated cost risks during the Planning, Engineering, & Design

phase of the project as more detailed design information becomes available.

2. Schedule Quality: As with the project costs, the schedule was developed based on

feasibility level information; the assumption of initiation date of Planning,

Engineering, & Design; and the appropriation construction funding date

anticipated by the WRDA legislation. It is recommended that project leadership

use the results of the schedule risk analysis in re-evaluating the schedule risk as

the project progresses forward and more definitive timeline of events becomes

available.

3. Risk Management: The outputs created during the risk analysis effort are

recommended to be used as tools in future risk management processes. The risk

register should be updated at each major project milestone. The results of the

sensitivity analysis may also be used for response planning strategy and


24

development. These tools should be used in conjunction with regular risk review

meetings. As an example, recommended uses of the risk register include:

Documenting risk mitigation strategies being pursued in response to the

identified risks and their assessment in terms of probability and impact.

Providing project sponsors, stakeholders, leadership, and management

with a documented framework from which risk status can be reported in

the context of project controls.

Communicating risk management issues.

Providing a mechanism for eliciting risk analysis feedback and project

control input.

Identifying risk transfer, elimination or mitigation actions required for

implementation of risk management plans.

4. Risk Analysis Updates: Project leadership should review risk items identified in

the original risk register and add others, as required, throughout the project lifecycle. Risks should be reviewed for status and reevaluation (using qualitative

measure, at a minimum) and placed on risk management watch lists if any risk’s

likelihood or impact significantly increases. Project leadership should also be

mindful of the potential for secondary (new risks created specifically by the

response to an original risk) and residual risks (risks that remain and have

unintended impact following response).

8. 0 REFERENCES

University of New Orleans and United States Geological Survey (UNO and USGS).

2009. Louisiana Barrier Island Comprehensive Monitoring Program (BICM) Volume 3:

Bathymetry and Historical Seafloor Change 18692007. Part 1: SouthCentral Louisiana

and Northern Chandeleur Islands, Bathymetry Methods and Uncertainty Analysis. Final

Report. January 2009.


ATTACHMENT A

Detailed Risk Registers


Likelihood* Impact* Risk Level*

Rough Order

Impact ($) Likelihood* Impact* Risk Level*

Rough Order

Impact (mo)

Correlation to

Other(s)

PPM-1 Available and Timely Funding Available funding from the Federal government. Very Unlikely Negligible Low Very Unlikely Significant Low

PPM-2 Changes in priority

Pulling funding for this project for other immediate needs. Competition for

resources. Very Unlikely Marginal Low Very Unlikely Critical Low

Whiskey BA 3 for marsh creation is not currently

considered in any other island restorations. The

TSP would utilize Ship Shoal material that was

previously considered for TE-47 Whiskey West

Flank project of which the TSP would replace.

PPM-3 Estimating/Scheduling Errors

Chance for oversights, errors, etc., as the schedule and scope of work ar

driving the estimate and schedule quality. Unlikely Marginal Low Unlikely Marginal Low

PPM-5

Functional Resources Overloaded/Shiftof Staff Priorities

Lack of internal human resources to execute project due to heavy

workload, overloaded staff, and shifting priorities. Unlikely Marginal Low Unlikely Marginal Low

PPM-8 Contract Acquisition Risks Decreasing competition Unlikely Marginal Low Unlikely Negligible Low

It is likely that it will be a FFP large business,

based on historical, and small business does not

have the capibility.

FW-1

Adaptive Management Plan & Monitoring(AMP) shortened duration

AMP may not require the full 10 years budgeted to determine ecological

success (opportunity) Unlikely Marginal Low Unlikely Negligible Low

A reduction in the AMP to 7 years equates to a

reduction in total project cost of 2%. However due

to the significance of the aquired data during this

period it is unlikely that the program would be

shortened.

FW-2 Survey cost escalation

Cost of field survey crews may be greater or less than budgeted. If greate

than budgeted, survey coverage would have to be reduced. If less than

budgeted, survey coverage could be expanded. Likely Negligible Low Likely Negligible Low

An increase of annual survey cost of 10% equates

to 0.5% of total project cost.

BR-1 MMS Survey Issues (30-m spacing)

Borrow areas in Federal Waters are under the jurisdiction of the MMS

which may enforce new survey spacing requirements, infrastructure

offsets etc. resulting in less available material or increased data acquisitio

and permitting costs. Although 50-m surveys were already conducted, the

30-m surveys might reveal additional CRs. Unlikely Negligible Low Unlikely Marginal Low

BR-2 Cultural Resources Island Specific

Raccoon, Whiskey, and Timbalier Island include high, medium, mediumprobability area (respectively) and will require remote sensing. Likely Negligible Low Likely Negligible Low A cultural resource survey is planned and will be conducted shortly for Whiskey Island (TSP).

BR-4 Regulatory and Environmental Risks

Ship Shoal dredging impacts, reviewing agency requires higher-level

review than assumed, permits take longer than expected, pressure to

compress the study and permitting activities Unlikely Marginal Low Unlikely Negligible Low

BR-8 Permitted Activities

Activities such as pipeline construction, canal maintenance and

construction on or near the project area that could affect project design,

access, or exacerbate current land loss rates. Unlikely Negligible Low Unlikely Negligible Low

There are no oil and gas infrastructure or pipelines

within the Whiskey Island fill templates.

BR-9 Pipeline from Borrow Area Navigation Issues, oyster issues. Unlikely Negligible Low Unlikely Negligible Low

BR-10

General Dredge Cost EstimatingAssumptions

Distance between island and borrow areas, weather days, dredge

mob/demob costs, plant costs Unlikely Marginal Low Unlikely Marginal Low

BR-13

Risk of Restoration Activates Damagingoil and gas facilities

Risk associated with oil and gas facilities including pipelines being

damaged during project activities. Spills associated with damages to

pipelines Unlikely Marginal Low Unlikely Marginal Low

Review of USGS and MMS pipeline databases

revealed that there are no known pipelines within

the borrow area or fill sites. There is one oil/gas

structure to the north of the island and one pipelin

leading to this structure from offshore through

Whiskey Pass.

BR-14

Contractor and other Constructionrelated Risks Inefficient contractor, conflicts with other contracts, site access, adequate staging areas, special equipment availability Unlikely Negligible Low Unlikely Negligible Low

Feature Code 01 - Real Estate

LCA TBBSR - NER Plan PDT Preliminary Risk Register

Contract Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)Project and Program Management

Discussion and Concerns Notes

Project Cost Project Schedule

Risk No. Risk/Opportunity Event

Variance

Distribution

Feature Code 06 - Fish & Wildlife (Adaptive Management Plan & Monitoring)

Environmental & CulturalConstruction

Feature Code 17 - Beach Replenishment (Beach and Marsh Construction)

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

ccurrence LikelihoodofO

Risk Level

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

ccurrence LikelihoodofO

Risk Level


PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated due to survey coverag

/ quality and or storms prior to or during construction. Likely Marginal Moderate Likely Marginal Moderate PR-12

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated due to survey coverag

/ quality and or storms prior to or during construction. Likely Marginal Moderate Likely Marginal Moderate PR-12

PED-3 Model Selection

If models applied do not take into account or were not developed to the

site-specific conditions of the Terrebonne Basin Barrier Shoreline, output

may result in under predicting or over predicting effectiveness of project. Very Unlikely Marginal Low Very Unlikely Marginal Low PED-4

PED-4 Model Input Error

If model inputs including bathymetry, topography, erosion, land change,

historic wave data, sediment grain size aren't representative of current

conditions, modeling output could result in flawed island templates. Unlikely Marginal Low Unlikely Marginal Low PED-3

PED-11

Geotechnical Issues Beach/Dune BorrowArea - South Pelto Borrow Area

Geotechnical conditions in the borrow areas and restoration areas may

differ from data reviewed during feasibility stage. Dredge volumes to mee

required fill volumes could differ. Unlikely Significant Moderate Unlikely Significant Moderate

PED-12

Geotechnical Issues Marsh Borrow Area -

South Pelto Borrow Area

Geotechnical conditions in the borrow areas and restoration areas may

differ from data reviewed during feasibility stage. Dredge volumes to mee

required fill volumes could differ. Unlikely Significant Moderate Unlikely Significant Moderate

PED-13

Geotechnical Issues Marsh Borrow Area -

Whiskey 3A Borrow Area Upper

Geotechnical conditions in the borrow areas and restoration areas may

differ from data reviewed during feasibility stage. Dredge volumes to mee

required fill volumes could differ. Unlikely Negligible Low Unlikely Negligible Low

PED-14

Geotechnical Issues Marsh Borrow Area -

Whiskey 3A Borrow Area Lower

Geotechnical conditions in the borrow areas and restoration areas may

differ from data reviewed during feasibility stage. Dredge volumes to mee

required fill volumes could differ. Unlikely Significant Moderate Unlikely Significant Moderate

PED-15

Geotechnical Issues Marsh Borrow Area -

New Cut Borrow Area

Geotechnical conditions in the borrow areas and restoration areas may

differ from data reviewed during feasibility stage. Dredge volumes to mee

required fill volumes could differ. Unlikely Significant Moderate Unlikely Significant Moderate

PED-16 Geophysical Data: All Borrow Areas

Borrow area volume calculations are based on existing surveys. Poor

data quality could result in volume shortages. Unlikely Marginal Low Unlikely Marginal Low

PED-18 Petroleum Infrastructure

Infrastructure could be installed within the borrow areas before

construction reducing the available material volumes Unlikely Marginal Low Unlikely Marginal Low BR-8

CM-1

PR-1 Sponsor's Ability to Fund Its Share

Procuring funds from the non-federal sponser has been known to take

long periods of time in the past. Likely Negligible Low Likely Significant High

PR-2 Fuel Prices Fluctuations in fuel costs could have an impact on the project cost. Likely Significant High Likely Negligible Low

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open Gulf especially during

winter season and during a severe tropical storm season. Effects on

dredge operational hours/day. Likely Significant High Likely Significant High

PR-4 Delays due to Design Modifications Modifications to design could be required at time of construction. Likely Negligible Low Likely Marginal Moderate

PR-5 Long Pipeline to Island from South Pelto

Risk in Productivity/efficiency with long pipeline and required number

boosters. Likely Significant High Likely Significant High

PR-7 Bidder's Risk in Volatile Market

Risk associated with bidders responding to volatile markets with higher b

prices. Likely Significant High Likely Negligible Low

PR-8 Pipeline Steel Prices Risks associated with changing steel prices increasing the cost of pipe. Likely Significant High Likely Negligible Low

PR-10 Dredge Acquisition Dredges for the project may not be available at all times. Unlikely Marginal Low Unlikely Significant Moderate

PR-11

Oil and Gas facilities damage (storms,accidental releases) resulting in damageto barrier resources

Adverse impacts to existing resources (baseline conditions) resulting from

accidental releases, ongoing activities. Unlikely Marginal Low Unlikely Marginal Low

Review of USGS and MMS pipeline databases

revealed that there are no known pipelines within

the borrow area or fill sites. There is one oil/gas

structure to the north of the island and one pipelin

leading to this structure from offshore through

Whiskey Pass.

PR-13 Shore equipment mechanical issues

Dozers etc. may experience mechanical issues causing downtime an

reducing productivity. Unlikely Negligible Low Unlikely Negligible Low

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to be moved off of an

island during construction due to a hurricane event Likely Marginal Moderate Likely Marginal Moderate

10. Project Implications identifies whether or not the risk item affects project cost, project schedule, or both. The PDT is responsible for conducting studies for both Project Cost and for Project Schedule.11. Results of the risk identification process are studied and further developed by the Cost Engineer, then analyzed through the Monte Carlo Analysis Method for Cost (Contingency) and Schedule (Escalation) Growth.

Programmatic Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

*Likelihood, Impact, and Risk Level to be verified through market research and analysis (conducted by cost engineer).5. Risk Level is the resultant of Likelihood and ImpactLow, Moderate, or High. Refer to top matrix table.4. Impact is a measure of the event's effect on project objectives with relation to scope, cost, and/or schedule --Negligible, Marginal, Significant, Critical, or Crisis. Impacts on Project Cost may not be the same for impacts on Project Schedule.

3. Likelihood is a measure of the probability of the event occurring --Very Unlikely, Unlikely, Moderately Likely, Likely, Very Likely. Likelihood of the event is the same for both Cost and Schedule.

1. Risk/Opportunity identified with reference to the Risk Identification Checklist and through deliberation and study of the PDT.2. Discussions and Concerns elaborates on Risk/Opportunity Events and includes any assumptions or findings (should contain information pertinent to eventual study and analysis of event's impact to project).

7. The responsibility or POC is the entity responsible as the Subject Matter Expert (SME) on the PDT for the identified risk or opportunity.8. Correlation recognizes those risk events that may be related to one another. Care should be given to ensure the risks are handled correctly without "9. Affected Project Component identifies the specific item of the project to which the risk directly or strongly correlates.

double counting."

6. Variance Distribution refers to the behavior of the individual risk item with respect to its potential effects on Project Cost and Schedule. For example, an item with clearly defined parameters and a solid most likely scenario would probably follow a

Feature Code 30 - Planning, Engineering & DesignFeature Code 31 - Construction Management

DesignGeotechnical & Survey


Risk No. Risk Event Issues Likelihood Impact

Cost Risk

Level Distribution Low Likely High

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-$5,705,251 $0 $5,637,530

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-$13,506,679 $0 $16,055,143

PED-11

Geotechnical IssuesBeach/Dune Borrow Area -Ship Shoal Borrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$3,649,948 $0 $21,040,482

PED-12

Geotechnical Issues MarshBorrow Area - Ship ShoalBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$535,093 $0 $3,139,480

PED-13

Geotechnical Issues MarshBorrow Area - Whiskey 3ABorrow Area Upper

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$3,711,136 $0 $7,282,898

PED-14

Geotechnical Issues MarshBorrow Area - RaccoonIsland Borrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$739,839 $0 $739,839

PR-2 Fuel Prices

Fluctuations in fuel costs could have an impact on

the project cost. Likely Significant High Triangular -$26,016,068 $0 $58,328,428

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open

Gulf especially during winter season and during a

severe tropical storm season. Likely Significant High Triangular

-$18,309,377 $0 $29,242,651

PR-5

Long Pipeline to Island fromShip Shoal

Risk in Productivity/efficiency with long pipeline and

required number boosters. Likely Significant High Uniform $0 $0 $19,882,759

PR-7

Bidder's Risk in VolatileMarket

Risk associated with bidders responding to volatile

markets with higher bid prices. Likely Significant High Triangular -$22,934,818 $0 $57,337,045

PR-8 Pipeline Steel Prices

Risks associated with changing steel prices

increasing the cost of pipe. Likely Significant High Triangular -$4,397,173 $0 $13,813,006

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to

be moved off of an island during construction due

to a hurricane event Likely Marginal Moderate Uniform

$0 $0 $1,539,351

All Other Project Cost(Placeholder) Placeholder to return to forcast value N/A N/A N/A

$260,222,247$260,222,247

LCA TBBSR - NER Plan Contract #1 (Whiskey Is., Trinity Is., Raccoon Is.) Cost Risk Analysis Simulation

Internal Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)External Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

Crystal Ball Simulation

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihood of Occurrence

Risk Level


Risk No. Risk Event Issues Likelihood Impact

Cost Risk

Level Distribution Low Likely High

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-$549,894 $0 $621,297

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-$761,717 $0 $761,717

PED-11

Geotechnical IssuesBeach/Dune - South PeltoBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$2,815,404 $0 $15,599,928

PED-12

Geotechnical Issues MarshBorrow Area - South PeltoBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$763,475 $0 $4,484,990

PED-14

Geotechnical Issues MarshBorrow Area - Whiskey 3ABorrow Area Lower

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$5,284,472 $0 $5,381,994

PED-15

Geotechnical Issues MarshBorrow Area - New CutBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-$1,158,579 $0 $1,158,579

PR-2 Fuel Prices

Fluctuations in fuel costs could have an impact on

the project cost. Likely Significant High Triangular -$25,815,596 $0 $56,827,221

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open

Gulf especially during winter season and during a

severe tropical storm season. Likely Significant High Triangular

-$21,105,860 $0 $29,690,244

PR-5

Long Pipeline to Island fromSouth Pelto

Risk in Productivity/efficiency with long pipeline and

required number boosters. Likely Significant High Uniform $0 $0 $27,416,784

PR-7

Bidder's Risk in VolatileMarket

Risk associated with bidders responding to volatile

markets with higher bid prices. Likely Significant High Triangular -$22,243,673 $0 $55,609,182

PR-8 Pipeline Steel Prices

Risks associated with changing steel prices

increasing the cost of pipe. Likely Significant High Triangular -$5,523,994 $0 $17,651,136

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to

be moved off of an island during construction due

to a hurricane event Likely Marginal Moderate Uniform

$0 $0 $875,272

All Other Project Cost(Placeholder) Placeholder to return to forcast value N/A N/A N/A

$245,062,710$245,062,710

LCA TBBSR - NER Plan Contract #2 (Timbalier Island) Cost Risk Analysis Simulation

Internal Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)External Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

Crystal Ball Simulation

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihood of Occurrence

Risk Level


Risk No. Risk Event Issues Likelihood Impact

Cost Risk

Level Distribution Low Likely High

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-1.23 0.00 1.21

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-1.50 0.00 2.29

PED-11

Geotechnical IssuesBeach/Dune Borrow Area -Ship Shoal Borrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.61 0.00 3.45

PED-12

Geotechnical Issues MarshBorrow Area - Ship ShoalBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.09 0.00 0.54

PED-13

Geotechnical Issues MarshBorrow Area - Whiskey 3ABorrow Area Upper

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.89 0.00 1.75

PED-14

Geotechnical Issues MarshBorrow Area - RaccoonIsland Borrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.18 0.00 0.18

PR-1

Sponsor's Ability to Fund ItsShare

Procuring funds from the non-federal sponser has

been known to take long periods of time in the past. Likely Significant High Uniform

0.00 0.00 18.00

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open

Gulf especially during winter season and during a

severe tropical storm season. Likely Significant High Triangular

-7.36 0.00 12.29

PR-4

Delays due to DesignModifications

Modifications to design could be required at time of

construction. Likely Marginal Moderate Uniform 0.00 0.00 6.00

PR-5

Long Pipeline to Island fromShip Shoal

Risk in Productivity/efficiency with long pipeline and

required number boosters. Likely Significant High Uniform

0.00 0.00 6.84

PR-10 Dredge Acquisition

Dredges for the project may not be available at all

times. Unlikely Significant Moderate Uniform

0.00 0.00 6.00

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to

be moved off of an island during construction due

to a hurricane event Likely Marginal Moderate Uniform

0.00 0.00 1.48

All Other Project Cost(Placeholder) Placeholder to return to forcast value N/A N/A N/A

64.5164.51

LCA TBBSR - NER Plan Contract #1 (Whiskey Is., Trinity Is., Raccoon Is.) Schedule Risk Analysis Simulation

Internal Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)External Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

Crystal Ball Simulation

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihood of Occurrence

Risk Level


Risk No. Risk Event Issues Likelihood Impact

Cost Risk

Level Distribution Low Likely High

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-1.43 0.00 1.43

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-1.56 0.00 1.56

PED-11

Geotechnical IssuesBeach/Dune - South PeltoBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.41 0.00 2.35

PED-12

Geotechnical Issues MarshBorrow Area - South PeltoBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.12 0.00 0.68

PED-14

Geotechnical Issues MarshBorrow Area - Whiskey 3ABorrow Area Lower

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.81 0.00 0.82

PED-15

Geotechnical Issues MarshBorrow Area - New CutBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. Unlikely Significant Moderate Triangular

-0.23 0.00 0.23

PR-1

Sponsor's Ability to Fund ItsShare

Procuring funds from the non-federal sponser has

been known to take long periods of time in the past. Likely Significant High Uniform

0.00 0.00 18.00

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open

Gulf especially during winter season and during a

severe tropical storm season. Likely Significant High Triangular

-7.23 0.00 10.21

PR-4

Delays due to DesignModifications

Modifications to design could be required at time of

construction. Likely Marginal Moderate Uniform 0.00 0.00 6.00

PR-5

Long Pipeline to Island fromSouth Pelto

Risk in Productivity/efficiency with long pipeline and

required number boosters. Likely Significant High Uniform

0.00 0.00 6.34

PR-10 Dredge Acquisition

Dredges for the project may not be available at all

times. Unlikely Significant Moderate Uniform

0.00 0.00 6.00

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to

be moved off of an island during construction due

to a hurricane event Likely Marginal Moderate Uniform

0.00 0.00 1.48

All Other Project Cost(Placeholder) Placeholder to return to forcast value N/A N/A N/A

55.8255.82

LCA TBBSR - NER Plan Contract #2 (Timbalier Island) Schedule Risk Analysis Simulation

Internal Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)External Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

Crystal Ball Simulation

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihood of Occurrence

Risk Level


Louisiana Coastal Authority

Terrebonne Basin Barrier Shoreline Restoration

Integrated Feasibility Study and

Environmental Impact Statement

Project Cost and Schedule Risk Analysis Report

First Component of Construction

Prepared for:

U.S. Army Corps of Engineers,

New Orleans District

Prepared by:

SJB Group, LLC. & Coastal Engineering Consultants, Inc.

Under contract from Louisiana Office of Coastal Protection and Restoration

August 2010


i

TABLE OF CONTENTS

EXECUTIVE SUMMARY ........................................................................................ ES-1

1.0 PURPOSE.....................................................................................................................1

2.0 BACKGROUND ..........................................................................................................1

2.1 PARTICIPATING AGENCIES .................................................................................1

2.2 STUDY AUTHORIZATION ....................................................................................1

2.3 STUDY PURPOSE................................................................................................2

2.4 STUDY LOCATION..............................................................................................2

2.5 FIRST COMPONENT OF CONSTRUCTION .............................................................3

3.0 REPORT SCOPE.........................................................................................................4

3.1 STUDY SCOPE ...................................................................................................4

3.2 USACE RISK ANALYSIS PROCESS....................................................................4

4.0 METHODOLOGY / PROCESS.................................................................................5

4.1 IDENTIFY POTENTIAL RISK FACTORS................................................................5

4.2 REFINE RISK REGISTER AND ASSIGN RISK LEVELS...........................................6

4.3 DEVELOP FINAL RISK REGISTER AND QUANTIFY RISK FACTORS .....................6

4.3.1 CONTINGENCY RISK FACTORS .............................................................7

4.4 RUN CRYSTAL BALL SIMULATIONS AND ANALYZE CONTINGENCIES ...............9

5.0 KEY ASSUMPTIONS...............................................................................................10

6.0 RISK ANALYSIS RESULTS ...................................................................................11

6.1 COST RISK ANALYSIS CONTINGENCY RESULTS ..............................................11

6.2 SCHEDULE RISK ANALYSIS CONTINGENCY RESULTS .....................................12

6.3 SENSITIVITY ANALYSIS RESULTS ...................................................................12

7.0 MAJOR FINDINGS / OBSERVATIONS / RECOMMENDATIONS .................14

7.1 MAJOR FINDINGS / OBSERVATIONS.................................................................14

7.2 RECOMMENDATIONS.......................................................................................19

8.0 REFERENCES...........................................................................................................20


ii

LIST OF TABLES

Table ES-1. Cost Summary - Program Year (2012) First Component of Construction

Initial Restoration Project Cost ...............................................................ES-1

Table ES-2. Cost Summary - Fully Funded First Component of Construction Initial

Restoration Project Cost ..........................................................................ES-2

Table 1. Topics and Work Breakdown Structure Analyzed ...............................................6

Table 2. First Component of Construction Initial Restoration Project Cost Estimate with

Contingencies Summary ....................................................................................11

Table 3. First Component of Construction Initial Restoration Project Construction

Schedule with Contingencies Summary ............................................................12

Table 4. Baseline Construction Cost Comparison Summary for the Initial Restoration of

the First Component of Construction.................................................................16

Table 5. Baseline Construction Schedule Comparison Summary for the Initial

Restoration of the First Component of Construction.........................................17

Table 6. Cost Summary - Program Year (2012) First Component of Construction Initial

Restoration Project Cost ....................................................................................18

Table 7. Cost Summary - Fully Funded First Component of Construction Initial

Restoration Project Cost ....................................................................................18

LIST OF FIGURES

Figure 1. First Component of Construction Initial Restoration Cost Sensitivity

Analysis..............................................................................................................13

Figure 2. First Component of Construction Initial Restoration Schedule Sensitivity

Analysis..............................................................................................................14

LIST OF APPENDICES

Detailed Risk Registers.......................................................................... ATTACHMENT A


ES-1

EXECUTIVE SUMMARY

This report presents a recommendation for the total project cost and schedule

contingencies for initial restoration of the first component of construction of the

Louisiana Coastal Authority, Terrebonne Basin Barrier Shoreline Restoration Study in

Terrebonne and Lafourche Parishes, Louisiana. The first component of construction

includes the initial restoration of Whiskey Island to a design of Plan C with

renourishment events in Target Year (TY) 20 and 40 following the initial restoration.

The renourishment in TY20 would be to a design of Plan C and in TY40 to a design of

Plan B. In compliance with Engineer Regulation (ER) 1110-2-1302 Civil Works Cost

Engineering, dated September 15, 2008, a formal risk analysis study was conducted for

the development of contingency on the total project cost for the initial restoration

exclusive of the operation and maintenance construction activities. The purpose of this

risk analysis study was to establish project contingencies by identifying and measuring

the cost and schedule impact of project uncertainties with respect to the estimated project

cost for the initial restoration of Whiskey Island.

The most likely program year (2012) baseline project cost for initial restoration is

estimated to be approximately $92.2 Million. Based on the results of the analysis it is

recommended that a contingency and escalation value of approximately $23.9 Million, or

28%, be added to the total project cost for a fully funded cost of $119.3 Million.

The following tables ES-1 and ES-2 present both the baseline cost and fully funded

project cost, respectively, of the initial restoration component for the first component of

construction based on the anticipated contract. The cost is intended to address the

congressional request of project cost estimates to implement the project. The contingency

is based on an 80% confidence level, as per U.S. Army Corps of Engineers Civil Works

guidance.


ES-2

Table ES-1. Cost Summary - Program Year (2012)

First Component of Construction Initial Restoration Project Cost

LCA TBBSR First Component of

Construction Total Project Costs

Program

Year Cost Contingency 1

Program

Year

Total Cost 2

01 Lands & Damages $51,238 $15,371 $66,609

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

17 Beach Replenishment $78,457,696 $21,732,782 $100,190,478

30 Planning, Engineering & Design $3,924,836 $1,087,180 $5,012,016

31 Construction Management $3,922,786 $1,086,612 $5,009,398

Total Project Costs $92,177,756 $23,921,945 $116,099,701

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

Table ES-2. Cost Summary - Fully Funded First Component of Construction

Initial Restoration Project Cost

LCA TBBSR First Component of

Construction Total Project Costs

Program

Year Cost

Total

Contingencies

&

Escalations 1

Fully

Funded

Total 2

01 Lands & Damages $51,238 $15,908 $67,146

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

17 Beach Replenishment $78,457,696 $24,773,119 $103,230,815

30 Planning, Engineering & Design $3,924,836 $1,118,110 $5,042,946

31 Construction Management $3,922,786 $1,235,170 $5,157,956

Total Project Costs $92,177,756 $27,142,306 $119,320,062

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

KEY FINDINGS/OBSERVATIONS/RECOMMENDATIONS

The key cost risk drivers identified through sensitivity analysis for the initial restoration

component of the first component of construction are Internal Risk PED-11 Geotechnical

Issues Beach/Dune Borrow Area) and External Risks PR-2 (Fuel Prices), PR-3 (Severe

Weather/Downtime), PR-5 (Long Pipeline to Island for Beach Fill), PR-7 (Bidder’s Risk

in Volatile Market) which together contribute 96.4% of the statistical cost variance.

The key schedule risk drivers identified through sensitivity analysis for the initial

restoration component of the first component of construction are External Risks PR-1


ES-3

(Sponsor’s Ability to Fund its Share), PR-3 (Severe Weather/Downtime), PR-5 (Long

Pipeline to Island for Beach Fill), and PR-10 (Dredge Acquisition), which together

contribute 91.8% of the statistical schedule variance.

Recommendations, as detailed within the main report, include the implementation of cost

and schedule contingencies, further iterative study of risks throughout the project lifecycle, potential mitigation throughout the Planning, Engineering & Design phase, and

proactive monitoring and control of risk identified in this study.


1

1.0 PURPOSE

The purpose of this report is to present the findings and results of the Cost and Schedule

Risk Analysis for the Louisiana Coastal Authority, Terrebonne Basin Barrier Shoreline

Restoration Study (LCA TBBSR). The results presented in this report include the

recommended contingencies to be added to the base estimate cost for the initial

restoration component of the first component of construction. Additionally, to provide

confidence that the actual project execution costs will be within the resulting estimated

budget value. Furthermore, the scope of the report includes the identification and

communication of important steps, logic, key assumptions, limitations, and decisions to

help ensure that risk analysis results can be appropriately interpreted. The results

presented herein are intended to provide project leadership with contingency information

for scheduling, budgeting, and project control purposes, as well as, provide tools to

support decision making and risk management as the project progresses through

Planning, Engineering & Design and project implementation.

2.0 Study BACKGROUND

2.1 PARTICIPATING AGENCIES

The responsible lead Federal agency for this study is the U. S. Army Corps of Engineers

(USACE) - Mississippi Valley, New Orleans District. The non-Federal sponsor for the

study is Louisiana Office of Coastal Protection and Restoration.

2.2 STUDY AUTHORIZATION

Title VII of the Water Resources Development Act (WRDA) 2007 authorizes the LCA

ecosystem restoration program. Included within that authority are requirements for

comprehensive coastal restoration planning, program governance, a Science and

Technology Program, a program for the beneficial use of dredged material, feasibility

studies for restoration plans, project modification investigations, and restoration project

construction, in addition to other program elements. This authorization was

recommended by the Chief of Engineer’s Report, dated January 31, 2005.

Under the 2007 WRDA Section 7006, the LCA program has authority for feasibilitylevel reports of six near-term critical restoration features of which includes the LCA

TBBSR Study.


2

2.3 STUDY PURPOSE

The purpose of the proposed action is to address the goal of the 2004 LCA Plan;

specifically, to address the critical near-term needs for shoreline restoration in

Terrebonne Basin through simulation of historical conditions, which will be achieved by

enlarging the existing barrier islands (width and dune crest) and reducing the current

number of breaches. Additional objectives include analyzing the current conditions of

the barrier islands, assessing impacts from the hurricanes of 2005 and 2008, and

reaffirming the validity of the findings of the Final Environmental Impact Statement. The

Integrated Feasibility Study and Environmental Impact Statement is based on a thorough

review of existing scientific and engineering reports, as well as geospatial, survey, and

geotechnical data.

2.4 STUDY LOCATION

The LCA TBBSR, located in LCA Subprovince 3, provides for the restoration of the

Timbalier and Isles Dernieres barrier island reaches located in Terrebonne and Lafourche

Parishes, Louisiana. The Study area is located in the 3rd Congressional District.

The Isles Dernieres Reach

The Isles Dernieres reach represents a barrier island arc approximately 22 miles long in

Terrebonne Parish and extends from Caillou Bay east to Cat Island Pass. Raccoon Island,

Whiskey Island, Trinity Island, East Island, and Wine Island, the primary islands that

comprise the Isles Dernieres barrier island chain, are backed by Bay Blanc, Bay Round,

Caillou Bay, and Terrebonne Bay, and bordered by the Gulf of Mexico on the seaward

side. The islands range from approximately 0.1 to 1.2 miles wide and are generally

composed of a thin sand cap over a thick mud platform. Elevations are generally low and

the islands are frequently over washed.

The Isles Dernieres have been and continue to be an important commercial and

recreational resource for Louisiana and the nation for more than 150 years. The islands

support habitats that are critical to the State’s commercial fishing industry. Furthermore,

the mineral-rich subsurface of the island range supports a high concentration of active oil

and gas wells.

The first major coastal resort in Louisiana was located here and was washed away by the

great hurricane of 1856. The Isles Dernieres have also been the location of five Coastal

Wetland Planning, Protection, and Restoration Act projects. These projects included:

Raccoon Island (TE-29), Whiskey Island (TE-27), Trinity Island (TE-24), East Island

(TE-20), and New Cut (TE-37).


3

The Timbalier Islands Reach

The Timbalier Islands reach is comprised of Timbalier Island and East Timbalier Island.

The two islands are on the western edge of the Lafourche barrier shoreline and are

located about 60 miles southwest of New Orleans, Louisiana. This barrier island

shoreline is approximately 20 miles long and backed by Terrebonne and Timbalier Bay to

the north and delimited by Raccoon Pass to the east and Cat Island Pass to the west. The

islands range from 0.1 to 0.6 miles wide and have low elevations. The Timbalier Islands

support onshore and offshore oil and gas development and production. Oil and gas

production facilities are prevalent along East Timbalier Island, while only a few scattered

facilities are present along Timbalier Island.

2.5 FIRST COMPONENT OF CONSTRUCTION

Whiskey Island Plan C was selected as initial restoration of the first component of

construction. The plan will create a total of 1,272 acres of barrier island habitat The

initial restoration includes the construction of 65 acres of dune, 830 acres of supratidal

habitat, and 377 acres of intertidal habitat. The initial restoration will be constructed on

the existing island footprint, which consists of 377 acres of supratidal habitat and 443

acres of intertidal habitat at TY0. Renourishment events are planned for Target Year

(TY) 20 and 40 following initial restoration. The renourishment events were not

evaluated in this risk analysis.

The barrier island restoration features of the initial restoration would achieve the planning

objectives by maximizing the barrier island’s ability to provide geomorphic and

hydrologic form and ecological function, as well as, improve critical barrier island

habitats for fish, migratory birds, and other terrestrial and aquatic species. Sediment

would be placed into the system to supplement long-shore sediment transport processes

along the gulf shoreline by mechanically introducing compatible sediment, and

increasing the ability of the restored area to continue to function and provide habitat with

minimum continuing intervention.

The selection of the first component of construction was based on a thorough review

of existing scientific and engineering reports, as well as geospatial, survey, and

geotechnical data which reaffirmed that the findings of the Final Environmental Impact

Statement remained valid.


4

3.0 REPORT SCOPE

3.1 STUDY SCOPE

Engineering Circular Bulletin (ECB) 2007-17, Application of Cost Risk Analysis

Methods to Develop Contingencies for Civil Works Total Project Costs (Sept. 10, 2007)

requires that a formal risk analysis be prepared for all decision documents requiring

Congressional authorization whose total costs are in excess of forty million dollars.

In addition to broadly defined risk analysis standards and recommended practices, a risk

analysis is to be performed to meet the requirements and recommendations of the

following documents and sources:

Cost and Schedule Risk Analysis Process guidance prepared by the USACE Cost

Engineering Directory of Expertise for Civil Works (Cost Engineering Dx), dated

May 17, 2009.

Engineer Regulation (ER) 1110-2-1302 Civil Works Cost Engineering, dated

Sept. 15, 2008.

Engineer Technical Letter (ETL) 1110-2-573 Construction Cost Estimating Guide

for Civil Works, dated Sept. 30, 2008.

3.2 USACE RISK ANALYSIS PROCESS

A risk analysis is performed to determine the probability of various cost and schedule

variances that could affect the total project cost. The analyses of the cost risk factors

associated with the project will determine the required contingency needed in the cost

estimate to achieve any desired level of cost confidence. A similar analysis is also used

to determine the probability of various project schedule duration impacts and then

quantify the required schedule contingency needed in the schedule to achieve any desired

level of schedule confidence. Together the contingency for both cost and schedule will

provide a total project cost and schedule at the desired confidence level.

The risk analysis process uses Monte Carlo techniques to determine probabilities and

contingency. The Monte Carlo techniques are facilitated computationally by a

commercially available risk analysis software package (Crystal Ball) that is an add-in to

Microsoft Excel. The software determines contingency amounts based on specific

‘confidence levels’. These confidence levels express the probability that the

corresponding contingency amount will cover the cost of the project being studied.


5

In general, the amount of contingency included in project control plans depends on the

project leadership’s willingness to accept risk of project overruns. The less risk that

project leadership is willing to accept, the more contingency that should be applied in the

project control plans. This risk of overrun is expressed by Crystal Ball in a probabilistic

context using confidence levels. The Cost Engineering Dx guidance for cost and schedule

risk analysis focuses on risk and opportunity potential, all project features, internal and

external risks to the project. The Cost Engineering Dx recommends budget presentation

with a contingency value at the eighty-percent level of confidence (80%) for successful

project execution within the established budget. This 80% confidence level is the

standard normally provided to Congress by USACE and other Government agencies.

4.0 METHODOLOGY / PROCESS

A risk analysis begins with the identification of risk factors for the restoration. The risk

identification process includes the major PDT members knowledgeable with the potential

impacts. The risks are then compared for commonalities with other risk factors and a

preliminary risk register is developed for risk level assignment. Following risk level

evaluation and assignment, those risk factor found to have 'moderate' or 'high' impact

risks are carried forward to the final risk register and quantified. The final risk register

serves as the risk models used within the Crystal Ball software. These primary steps of

the risk analysis process, in functional terms, are described in the following subsections.

4.1 IDENTIFY POTENTIAL RISK FACTORS

The risk analysis process began with a brainstorming session to identify any and all

potential risk factors associated with the project. These potential risks were then

evaluated to determine if correlations existed between any of the potential risk factors.

Risk factors that were determined to have correlations were analyzed to determine the

nature of the correlation. If strong correlations existed then the factors were combined

into a single risk factor. If correlations were determined wherein the risk factors had

similarities but contained inherent differences, the factors were revised and/or additional

risk factors were added such that all risks could be evaluated individually.

The risks developed and refined during the brainstorming sessions were transferred into a

risk register template in Microsoft Excel as the Initial Risk Register (Attachment A).

4.2 REFINE RISK REGISTER AND ASSIGN RISK LEVELS

The initial risk register was structured such that elements of risk were assigned under a

topic and feature code and given a risk factor number allowing traceability throughout the


6

process. Similar to the identification and assessment process, risk factor quantification

involved the evaluation of the impact of the risk on the project. The risk factors were

assigned a likelihood of occurrence and a level of impact the risk would have on the

project cost or schedule. Table 1 provides a listing of the topics and feature codes

evaluated in this risk assessment.

Table 1. Topics and Work Breakdown Structure Analyzed

PPM Project and Program Management

01 Lands and Damages

06 Fish & Wildlife (Adaptive Management Plan)

17 Beach Replenishment

30 Planning, Engineering & Design

31 Construction Management

PR Programmatic Risks

4.3 DEVELOP FINAL RISK REGISTER AND QUANTIFY RISK FACTORS

Those risk factors determined to have a 'moderate' or 'high' impact on the project cost or

schedule were carried forward to the final risk register and quantified.

The quantification process involved collaboration between the ATR review lead, District

cost engineers, and the A/E cost estimators. This process used an iterative approach to

estimate the following elements of each risk factor:

Maximum possible value for the risk factor (high value, worst-case)

Minimum possible value for the risk factor (low value, best-case)

Most likely value (the original estimate value, if applicable)

Nature of the probability density function used to approximate risk factor

uncertainty

Correlations between risk factors

Affected cost and/or schedule elements

Information was extracted from the cost estimates and placed into the final cost risk

register for cost risk analysis purposes (Attachment A). For the schedule risk analysis, the

durations for each risk (if applicable) were placed into a final schedule risk register

(Attachment A).


7

4.3.1 Contingency Risk Factors

The following are those elements analyzed in the cost and schedule risk models to

determine the appropriate contingencies.

4.3.1.1 Beach/Dune and Marsh Fill Design Quantities (Cost & Schedule)

The island design was developed utilizing survey data collected in 2006 as part of the

Louisiana Barrier Island Comprehensive Monitoring Program (UNO and USGS, 2009).

Through the use of shoreline erosion and landloss rates in the above referenced program,

the fill volumes required in 2012 for beach/dune and marsh were calculated. A risk

variance of +/-10% of the required volume was used to evaluate the risk associated with a

decrease or increase in the erosional effects experienced by the island during this six year

period in addition to a storm event proceeding or during construction. The variances in

beach/dune and marsh required volumes were analyzed as separate risk elements so as to

assess the risk if the beach/dune and marsh fill template experience differing erosional

influences.

4.3.1.2 Geotechnical Issues with the Beach/Dune and Marsh Fill Borrow Areas

(Cost and Schedule)

The sediment characteristics of the proposed borrow areas for beach/dune and marsh

construction were analyzed from data collected within these borrow sources as part of

designs for other restoration projects. Projected dredge-to-fill ratios were established and

used in the production estimates for the dredge during construction of the beach/dune and

marsh fill templates. To quantify variances induced by differing sediment characteristics

that could be experienced within the borrow areas proposed for beach/dune fill and the

marsh fill, differing ratios better than and worse than the most likely dredge-to-fill were

evaluated for their affect on the construction cost. Sediment characteristics are one of

three driving forces in determining production rates for the dredging equipment.

4.3.1.3 Sponsor's Ability to Fund Its Share (Schedule)

A delay of six months in the procurement of funds to begin construction of the project

was evaluated. The low risk was assumed to be the same as the most likely schedule for

construction. The high risk was analyzed at a delay of six months for the beginning of

construction.


8

4.3.1.4 Fuel Prices (Cost)

Overall affects of fuel prices on construction cost were analyzed. The most likely fuel

price was derived from an average of fuel prices for 2009. A lower risk assumes the

price of fuel would fall by as much as 25% from the 2009 average. A higher risk

assumes that a volatile market could increase fuel prices by as much as 60% above the

2009 average price.

4.3.1.5 Severe Weather Downtime (Cost & Schedule)

The effects of dredging material in the open Gulf of Mexico on the dredge's effective

operational hours per day were evaluated. A dredge may experience higher average

operational time per day during periods of favorable weather and conversely experience

lower than average operational time during periods of increases sea state such as during

winter months. The most likely, worst case, and best case operational time per day were

established by review of USACE prior dredging projects. Operational time of the

dredging equipment is one of three driving forces in determining production rates for the

dredging equipment.

4.3.1.6 Delays due to Design Modifications (Schedule)

Following pre-construction surveys of the fill templates, design modification may be

required to adjust the fill templates to maximize effectiveness of the island restoration.

Through prior restoration project experience of the design team, a two month delay in

beginning construction was considered as the high risk variance for the project schedule.

4.3.1.7 Long Pipeline to Island for Beach/Dune Fill (Cost & Schedule)

In development of the dredging production rates, it was determined that it was feasible to

construct the beach/dune fill template using as few as two boosters from the borrow area

to the fill template. The most likely number of boosters the contractor would use is three

to maintain higher production rates. The number of booster pumps utilized in the

delivery of sediment to the fill template is one of three driving forces in determining the

production rates for the dredging equipment. Construction cost and schedule variances

were calculated to evaluate the affects on project cost and schedule if the contractor chose

to utilize only two booster pumps during the construction of the beach/dune fill template.


9

4.3.1.8 Bidder's Risk in a Volatile Market (Cost)

The affects on construction cost of based on the risk assumed by the contractor were

analyzed. These risks are those carried by the contractors that are not analyzed in other

risk elements of this model. Those risks analyzed elsewhere include fuel prices, pipeline

steel prices, weather delays, dredge acquisition, and additional mobilizations due to

hurricanes. Examples of volatile market risk include, but are not limited to, other

projects out for bid requiring the contractor's resources, labor force prices, and

construction equipment availability. A low risk assumes the contractor is eager for the

contract and would bid 10% less than the most likely and conversely a high risk indicates

the contractor may be over extending his resources and submits a bid 25% higher than the

most likely construction cost.

4.3.1.9 Pipeline Steel Prices (Cost)

The risk associated with the changing price per pound of steel was analyzed to determine

it's affect on the cost of the sediment delivery pipeline. Utilizing pricing from prior

USACE projects, the assumed current cost per pound for steel was set a $0.60, the low

price at $0.45, and the high price at $1.50. These prices were used in the determination

of unit cost variances for beach/dune and marsh fill.

4.3.1.10 Dredge Acquisition (Schedule)

The risk associated with the availability of dredges for restoration construction at the time

of notice to proceed for the contractor was considered. The delay to the construction

schedule, while awaiting a dredge to become available from another project, was

determined to be 6 months.

4.3.1.11 Hurricane Demobilization/Re-mobilization (Cost & Schedule)

For the possibility of a hurricane affecting the project during construction, an additional

demobilization/re-mobilization of the crew, equipment, and dredge to safe harbor was

evaluated.

4.4 RUN CRYSTAL BALL SIMULATIONS AND ANALYZE CONTINGENCIES

Once the risk factors were refined into the final risk resisters for cost and schedule, the

final quantitative impacts of risk factors served as the risk model and were analyzed using

a combination of professional judgment, empirical data and analytical techniques. The

software uses the most likely, low, and high values for various risks. The most likely


10

value is usually the value used in the cost estimate. The low and high values, or best-case

and worst-case values, are quantified based off a number of factors, including, but not

limited to, the cost estimate. The software uses these values in conjunction with the

associated probability distribution assigned to each risk to run its Monte Carlo

simulations. Once the software has finished its simulation the total cost of the project

with contingency is forecast for specific confidence levels. The resulting 80% confidence

level contingency amount is the difference between the 80% cost forecast and the base

cost estimate. For schedule contingency analysis, the contingency was calculated as the

difference between the 80% level duration forecast and the base schedule duration,

shown in months. These new durations suggested by the 80% confidence level were then

incorporated into the escalation calculation, i.e., the escalation of the baseline estimate of

cost in the Total Project Cost Summary (TPCS) of the initial restoration of the first

component of construction.

The forecasts for cost and/or schedule risk can then be analyzed to determine the

recommended level of contingency for the project. As stated earlier, the contingencies

suggested by the higher confidence levels will account for more risk in the project;

conversely, the amounts suggested by the lower confidence levels could possible leave

the project without sufficient funding if some events do not go as planned.

5.0 KEY ASSUMPTIONS

Key assumptions are those that are most likely to affect the determinations and/or

estimates of risk presented in the risk analysis. The key assumptions are important to help

ensure that project leadership and other decision makers understand the steps, logic,

limitations, and decisions made in the risk analysis, as well as any resultant limitations on

the use of outcomes and results. For this project, the assumptions include:

1. Level of Design: The cost comparisons and risk analyses performed and reflected

within this report are based upon design scope and estimates that are considered

to be well developed and designed.

2. Design Scope: The prescribed scope satisfies the requirements of this acquisition.

3. Operation and Maintenance: Operation and maintenance activities were not

included in the cost estimate or schedules, because none were planned for the

selected alternative.

4. Contract Acquisition Strategy: Consistent with cost estimate and schedule

assumptions, it is assumed that the contract acquisition strategy is firm fixed

price.

5. Confidence Levels: The Wall Walla Cost Engineering Dx guidance generally

focuses on the eighty-percent level of confidence (80%) for cost contingency


11

calculation. For this risk analysis, the eighty-percent level of confidence (80%)

was used. It should be noted that the use of 80% as a decision criteria is a

moderately risk averse approach, generally resulting in higher cost contingencies.

However, the 80% level of confidence also assumes a small degree of risk that the

recommended contingencies may be inadequate to completely capture actual

project costs.

6.0 RISK ANALYSIS RESULTS

The cost and schedule risk analysis results are provided in the following sections. In

addition to contingency calculation results, sensitivity analyses are presented to provide

decision makers with an understanding of variability and the key contributors to the cause

of this variability.

6.1 COST RISK ANALYSIS CONTINGENCY RESULTS

The construction cost contingencies calculated for the 80% confidence level and rounded

to the nearest thousand are shown in Table 2. The construction cost contingencies for the

50% and 100% confidence levels are also provided for illustrative purposes.

The Mii cost estimate produced by USACE-MVN Cost Engineering and A/E cost

estimators with review by the ATR review lead provide initial construction costs of $90.1

Million for the initial restoration with a price level of the estimate in the 1st quarter 2010.

At the 80% confidence level, the base estimate construction cost contingency was

quantified as approximately $23.3 Million, with a baseline cost of $113.4 Million.

Table 2. First Component of Construction Initial Restoration

Project Cost Estimate with Contingencies Summary

Contingency Level

MII Cost

Estimate

($1,000)

Contingency

Percentage

Total

Contingency

($1,000) 1

Baseline Cost

Estimate

($1,000) 2

50% Confidence Level -

Initial Restoration

Project Cost

$90,091 18.4% $16,602 $106,693

80% Confidence Level -

Initial Restoration

Project Cost

$90,091 27.7% $24,988 $115,079

100% Confidence Level -

Initial Restoration

Project Cost

$90,091 59.2% $53,320 $143,411

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from Risk Analysis Forecast


12

6.2 SCHEDULE RISK ANALYSIS CONTINGENCY RESULTS

The original estimate of PED and construction duration for the initial restoration was 34.6

months. At the 80% confidence level, the projected duration for construction was 46.3

months – an increase of 34%. The schedule contingency was calculated by applying the

moderate and high level schedule risks identified in the risk register for each option to the

durations of critical path and near critical path tasks.

Table 3. First Component of Construction Initial Restoration

Project Construction Schedule with Contingencies Summary

Risk Analysis Forecast Forecast

Schedule

Total

Contingency

Crystal Ball

Forecast

Schedule

50% Confidence Level -

Initial Restoration

Project Duration

34.6 months 26% 43.7 months

80% Confidence LevelInitial Restoration

Project Duration

34.6 months 34% 46.3 months

100% Confidence Level -

Initial Restoration

Project Duration

34.6 months 55% 53.5 months

6.3 SENSITIVITY ANALYSIS RESULTS

Sensitivity analysis ranks the relative impact of each risk/opportunity as a percentage of

total cost uncertainty. The Crystal Ball software uses a statistical measure (contribution to

variance) that approximates the impact of each risk or opportunity contributing to

variability of cost outcomes during the Monte Carlo simulations.

The risks or opportunities that are considered as key drivers are ranked in the order of

significance to the total project costs variances. Risks are shown with a positive sign to

reflect the potential to increase project cost. Opportunities that have a potential to reduce

project cost and are shown with a negative sign. A longer bar in the sensitivity analysis

chart indicates the risk has a greater potential impact to total project cost.

Figure 1 presents the sensitivity analyses for cost growth for those risks identified in the

risk register as having a moderate to high level of impact. Similarly, Figure 2 presents a

sensitivity analysis for schedule growth risk.

The key cost risk drivers identified through sensitivity analysis for the initial restoration

component of the first component of construction are Internal Risk PED-11 Geotechnical


13

Issues Beach/Dune Borrow Area) and External Risks PR-2 (Fuel Prices), PR-3 (Severe

Weather/Downtime), PR-5 (Long Pipeline to Island for Beach Fill), PR-7 (Bidder’s Risk

in Volatile Market) which together contribute 96.4% of the statistical cost variance.

The key schedule risk drivers identified through sensitivity analysis for the initial

restoration component of the first component of construction are External Risks PR-1

(Sponsor’s Ability to Fund its Share), PR-3 (Severe Weather/Downtime), PR-5 (Long

Pipeline to Island for Beach Fill), and PR-10 (Dredge Acquisition), which together

contribute 91.8% of the statistical schedule variance.

Figure 1. First Component of Construction Initial Restoration

Cost Sensitivity Analysis


14

Figure 2. First Component of Construction Initial Restoration

Schedule Sensitivity Analysis

7. 0 MAJOR FINDINGS / OBSERVATIONS / RECOMMENDATION

This section provides a summary of the significant risk analysis results that were

identified in the preceding sections of the report. Risk analysis results are intended to

provide project leadership with contingency information for scheduling, budgeting, and

project control purposes, as well as to provide tools to support decision making and risk

management as projects progress through planning and implementation. Because of the

potential for use of risk analysis results for such diverse purposes, this section also

reiterates and highlights important steps, logic, key assumptions, limitations, and

decisions to help ensure that the risk analysis results are appropriately interpreted.

7.1 MAJOR FINDINGS / OBSERVATIONS

The total construction cost and schedule comparison summaries from Crystal Ball are

provided in Tables 5 and 6, respectively. Additional major findings and observations of

the risk analysis are listed below.


15

1. Base cost contingency recommended for the initial restoration of the first

component of construction is approximately $23.3 Million, for a total cost of

approximately $113.4 Million. This figure is derived from the 80% confidence

level values calculated by Crystal Ball (Table 4). It should be noted that the

contingency cost calculated by the TPCS are slightly lower because the cost

contingency and escalation are inclusive in the program cost provided by the

Adaptive Management Plan development team and therefore not calculated by the

TPCS.

2. Schedule duration contingency recommended for the initial restoration of the first

component of construction is 11.6 months, for a total duration of 46.3 months.

This monthly duration contingency is reflective of the 80% confidence level

values calculated by Crystal Ball (Table 5).

3. As shown in Figures 1 and 2, the cost risk and schedule risk for initial restoration

of the first component of construction are mostly dependent on two risk factors

each.

4. Operation and maintenance activities were not included in the presented cost

estimate or schedules. Therefore, a full lifecycle risk analysis could not be

performed. Risk analysis results or conclusions could be significantly different if

operation and maintenance activities were included.


16

Table 4. Baseline Construction Cost Comparison Summary for the Initial

Restoration of the First Component of Construction

Forecast:

TOTAL

PROJECT

COST

Percentile Forecast

values

0% $74,800,821

5% $91,873,811

10% $94,897,412

15% $96,990,201

20% $98,741,687

25% $100,219,322

30% $101,587,141

35% $102,919,229

40% $104,242,060

45% $105,478,621

50% $106,693,400

55% $107,926,332

60% $109,192,163

65% $110,504,078

70% $111,882,252

75% $113,402,851

80% $115,078,520

85% $117,028,899

90% $119,521,613

95% $123,159,649

100% $143,410,786

Minimum $74,800,821

Maximum $143,410,786

80% Confidence Level: $115,078,520

Original Project Cost: $90,089,312

Total Contingency Based on 80%

Confidence: 27.7%


17

Table 5. Baseline Construction Schedule Comparison Summary for the Initial

Restoration of the First Component of Construction

Forecast:

TOTAL

PROJECT

SCHEDULE

Percentile Forecast

values

0% 33.1

5% 38.8

10% 39.8

15% 40.6

20% 41.1

25% 41.6

30% 42.1

35% 42.5

40% 42.9

45% 43.3

50% 43.7

55% 44.1

60% 44.5

65% 44.9

70% 45.3

75% 45.8

80% 46.3

85% 46.8

90% 47.6

95% 48.6

100% 53.5

Minimum 33.1

Maximum 53.5

80% Confidence Level: 46.3

Original Project Cost: 34.6

Total Contingency Based on 80%

Confidence: 33.7%


18

Through utilization of the TPCS, the base cost estimate for the initial restoration from the

Mii escalated to the project year of the 1st quarter 2012 equals approximately $92.1

Million. Adding the cost and schedule influence contingencies provides a project cost of

approximately $116.1 Million. A breakdown of the program year cost by work feature is

presented in Table 6.

Table 6. Cost Summary - Program Year (2012)

First Component of Construction Initial Restoration Project Cost

LCA TBBSR First Component of

Construction Total Project Costs

Program

Year Cost 2 Contingency 1

Program

Year Total

Cost 2

01 Lands & Damages $51,238 $15,371 $66,609

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

17 Beach Replenishment $78,457,696 $21,732,782 $100,190,478

30 Planning, Engineering & Design $3,924,836 $1,087,180 $5,012,016

31 Construction Management $3,922,786 $1,086,612 $5,009,398

Total Project Costs $92,177,756 $23,921,945 $116,099,701

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS

Expanding on the program year cost estimate, escalation to midpoint of work features can

be calculated. The results provide a fully funded project cost of approximately $119.3

Million. A breakdown of the fully funded project cast is presented in Table 7.

Table 7. Cost Summary - Fully Funded First Component of Construction

Initial Restoration Project Cost

LCA TBBSR First Component of

Construction Total Project Costs

Program

Year Cost 2

All

Contingencies

& Escalations 1

Fully

Funded

Total 2

01 Lands & Damages $51,238 $15,908 $67,146

06 Fish & Wildlife

(Adaptive Management Plan) $5,821,200 Included $5,821,200

17 Beach Replenishment $78,457,696 $24,773,119 $103,230,815

30 Planning, Engineering & Design $3,924,836 $1,118,110 $5,042,946

31 Construction Management $3,922,786 $1,235,170 $5,157,956

Total Project Costs $92,177,756 $27,142,306 $119,320,062

Notes: 1. Adaptive Management Plan cost includes prior escalation & contingency and is subjected to the

Total Contingency and Escalation.

2. Costs taken from TPCS


19

7.2 RECOMMENDATIONS

Risk Management is an all-encompassing, iterative, and life-cycle process of project

management. The Project Management Institute’s (PMI) A Guide to the Project

Management Body of Knowledge (PMBOK® Guide), 4th edition, states that “project

risk management includes the processes concerned with conducting risk management

planning, identification, analysis, responses, and monitoring and control on a project.”

Risk identification and analysis are processes within the knowledge area of risk

management. Its outputs pertinent to this effort include the risk register, risk

quantification (risk analysis model), contingency report, and the sensitivity analysis.

The intended use of these outputs is implementation by the project leadership with

respect to risk responses (such as mitigation) and risk monitoring and control. In short,

the effectiveness of the project risk management effort requires that the proactive

management of risks not conclude with the study completed in this report.

This section provides a list of recommendations for continued management of the risks

identified and analyzed in this study. (Note: this list is not all-inclusive)

1. Cost Estimate Quality: The cost estimate was developed for the restoration of

Whiskey Island based on feasibility level surveys and designs. Risks associated

with the information utilized in the designs have been analyzed within this risk

assessment. It is recommended that the project leadership, restoration design

team, and project cost estimators work closely in re-evaluating the project cost

elements and associated cost risks during the Planning, Engineering, & Design

phase of the project as more detailed design information becomes available.

2. Schedule Quality: As with the project costs, the schedule was developed based on

feasibility level information; the assumption of initiation date of Planning,

Engineering, & Design; and the appropriation construction funding date

anticipated by the WRDA legislation. It is recommended that project leadership

use the results of the schedule risk analysis in re-evaluating the schedule risk as

the project progresses forward and more definitive timeline of events becomes

available.

3. Risk Management: The outputs created during the risk analysis effort are

recommended to be used as tools in future risk management processes. The risk

register should be updated at each major project milestone. The results of the

sensitivity analysis may also be used for response planning strategy and


20

development. These tools should be used in conjunction with regular risk review

meetings. As an example, recommended uses of the risk register include:

Documenting risk mitigation strategies being pursued in response to the

identified risks and their assessment in terms of probability and impact.

Providing project sponsors, stakeholders, leadership, and management

with a documented framework from which risk status can be reported in

the context of project controls.

Communicating risk management issues.

Providing a mechanism for eliciting risk analysis feedback and project

control input.

Identifying risk transfer, elimination or mitigation actions required for

implementation of risk management plans.

4. Risk Analysis Updates: Project leadership should review risk items identified in

the original risk register and add others, as required, throughout the project lifecycle. Risks should be reviewed for status and reevaluation (using qualitative

measure, at a minimum) and placed on risk management watch lists if any risk’s

likelihood or impact significantly increases. Project leadership should also be

mindful of the potential for secondary (new risks created specifically by the

response to an original risk) and residual risks (risks that remain and have

unintended impact following response).

8. 0 REFERENCES

University of New Orleans and United States Geological Survey (UNO and USGS).

2009. Louisiana Barrier Island Comprehensive Monitoring Program (BICM) Volume 3:

Bathymetry and Historical Seafloor Change 18692007. Part 1: SouthCentral Louisiana

and Northern Chandeleur Islands, Bathymetry Methods and Uncertainty Analysis. Final

Report. January 2009.


ATTACHMENT A

Detailed Risk Registers


Likelihood* Impact* Risk Level*

Rough Order

Impact ($) Likelihood* Impact* Risk Level*

Rough Order

Impact (mo)

Correlation to

Other(s)

PPM-1 Available and Timely Funding Available funding from the Federal government. Very Unlikely Negligible Low Very Unlikely Significant Low

PPM-2 Changes in priority

Pulling funding for this project for other immediate needs.

Competition for resources. Very Unlikely Marginal Low Very Unlikely Critical Low

Whiskey BA 3 for marsh creation is not currently

considered in any other island restorations. The

TSP would utilize Ship Shoal material that was

previously considered for TE-47 Whiskey West

Flank project of which the TSP would replace.

PPM-3 Estimating/Scheduling Errors

Chance for oversights, errors, etc., as the schedule and scope

of work are driving the estimate and schedule quality. Unlikely Marginal Low Unlikely Marginal Low

PPM-5

Functional ResourcesOverloaded/Shift of Staff Priorities

Lack of internal human resources to execute project due to

heavy workload, overloaded staff, and shifting priorities. Unlikely Marginal Low Unlikely Marginal Low

PPM-8 Contract Acquisition Risks Decreasing competition Unlikely Marginal Low Unlikely Negligible Low

It is likely that it will be a FFP large business,

based on historical, and small business does not

have the capibility.

FW-1

Adaptive Management Plan &Monitoring (AMP) shortened duration

AMP may not require the full 10 years budgeted to determine

ecological success (opportunity) Unlikely Marginal Low Unlikely Negligible Low

A reduction in the AMP to 7 years equates to a

reduction in total project cost of 2%. However due

to the significance of the aquired data during this

period it is unlikely that the program would be

shortened.

FW-2 Survey cost escalation

Cost of field survey crews may be greater or less than

budgeted. If greater than budgeted, survey coverage would

have to be reduced. If less than budgeted, survey coverage

could be expanded. Likely Negligible Low Likely Negligible Low

An increase of annual survey cost of 10% equates

to 0.5% of total project cost.

BR-1 MMS Survey Issues (30-m spacing)

Borrow areas in Federal Waters are under the jurisdiction of

the MMS which may enforce new survey spacing

requirements, infrastructure offsets etc. resulting in less

available material or increased data acquisition and permitting

costs. Although 50-m surveys were already conducted, the 30-

m surveys might reveal additional CRs. Unlikely Negligible Low Unlikely Marginal Low

BR-2 Cultural Resources Island Specific

Raccoon, Whiskey, and Timbalier Island include high, medium

medium-probability area (respectively) and will require remote

sensing. Likely Negligible Low Likely Negligible Low

A cultural resource survey is planned and will be

conducted shortly for Whiskey Island (TSP).

BR-4 Regulatory and Environmental Risks

Ship Shoal dredging impacts, reviewing agency requires highe

level review than assumed, permits take longer than expected,

pressure to compress the study and permitting activities Unlikely Marginal Low Unlikely Negligible Low

BR-6 Threatened & Endangered Species

Local birds and turtles could pose some threat to

cost/schedule. Piping Plover Very Unlikely Negligible Low Very Unlikely Marginal Low

USFW letter supporting project and willingness to

work through nesting issues. TSP one island

therefore providing nesting relocation.

BR-8 Permitted Activities

Activities such as pipeline construction, canal maintenance an

construction on or near the project area that could affect

project design, access, or exacerbate current land loss rates. Unlikely Negligible Low Unlikely Negligible Low

There are no oil and gas infrastructure or pipelines

within the Whiskey Island fill templates.

BR-9 Pipeline from Borrow Area Navigation Issues, oyster issues. Unlikely Negligible Low Unlikely Negligible Low

BR-10

General Dredge Cost EstimatingAssumptions

Distance between island and borrow areas, weather days,

dredge mob/demob costs, plant costs Unlikely Marginal Low Unlikely Marginal Low

Risk/Opportunity Event

Feature Code 01 - Real EstateFeature Code 06 - Fish & Wildlife (Adaptive Management Plan & Monitoring)

Environmental & CulturalConstruction

Feature Code 17 - Beach Replenishment (Beach and Marsh Construction)

LCA TBBSR - First Component of Construction PDT Preliminary Risk Register

Contract Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)Project and Program Management

Discussion and Concerns Notes

Project Cost Project Schedule

Risk No.

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihoodof Occurrence

Risk Level

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihoodof Occurrence

Risk Level


BR-13

Risk of Restoration ActivatesDamaging oil and gas facilities

Risk associated with oil and gas facilities including pipelines

being damaged during project activities. Spills associated with

damages to pipelines Very Unlikely Significant Low Very Unlikely Marginal Low

Review of USGS and MMS pipeline databases

revealed that there are no known pipelines within

the borrow area or fill sites. There is one oil/gas

structure to the north of the island and one pipelin

leading to this structure from offshore through

Whiskey Pass.

BR-14

Contractor and other Constructionrelated Risks Inefficient contractor, conflicts with other contracts, site access, adequate staging areas, special equipment availability Unlikely Negligible Low Unlikely Negligible Low

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated due to

survey coverage / quality and or storms prior to or during

construction. Likely Marginal Moderate Likely Marginal Moderate PR-12

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated due to

survey coverage / quality and or storms prior to or during

construction. Likely Marginal Moderate Likely Significant High PR-12

PED-3 Model Selection

If models applied do not take into account or were not

developed to the site-specific conditions of the Terrebonne

Basin Barrier Shoreline, output may result in under predicting

or over predicting effectiveness of project. Very Unlikely Marginal Low Very Unlikely Marginal Low PED-4

PED-4 Model Input Error

If model inputs including bathymetry, topography, erosion, land

change, historic wave data, sediment grain size aren't

representative of current conditions, modeling output could

result in flawed island templates. Unlikely Marginal Low Unlikely Marginal Low PED-3

PED-11

Geotechnical Issues Beach/DuneBorrow Area

Geotechnical conditions in the borrow areas and restoration

areas may differ from data reviewed during feasibility stage.

Dredge volumes to meet required fill volumes could differ. Unlikely Significant Moderate Unlikely Significant Moderate

PED-12

Geotechnical Issues Marsh BorrowArea

Geotechnical conditions in the borrow areas and restoration

areas may differ from data reviewed during feasibility stage.

Dredge volumes to meet required fill volumes could differ. Unlikely Significant Moderate Unlikely Significant Moderate

PED-13 Geophysical Data: Borrow Area

Borrow area volume calculations are based on existing survey

Poor data quality could result in volume shortages. Unlikely Marginal Low Unlikely Marginal Low

PED-15 Petroleum Infrastructure

Infrastructure could be installed within the borrow areas before

construction reducing the available material volumes Unlikely Marginal Low Unlikely Marginal Low BR-8

CM-1

PR-1 Sponsor's Ability to Fund Its Share

Procuring funds from the non-federal sponser has been known

to take long periods of time in the past. Likely Negligible Low Likely Significant High

PR-2 Fuel Prices

Fluctuations in fuel costs could have an impact on the projec

cost. Likely Significant High Likely Negligible Low

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open Gulf

especially during winter season and during a severe tropical

storm season. Effects on dredge operational hours/day. Likely Significant High Likely Significant High

PR-4 Delays due to Design Modifications

Modifications to design could be required at time of

construction. Likely Negligible Low Likely Significant High

PR-5 Long Pipeline to Island for Beach Fill

Risk in Productivity/efficiency with long pipeline and required

number boosters. Likely Significant High Likely Significant High

PR-7 Bidder's Risk in Volatile Market

Risk associated with bidders responding to volatile markets

with higher bid prices. Likely Significant High Likely Negligible Low

PR-8 Pipeline Steel Prices

Risks associated with changing steel prices increasing the cos

of pipe. Likely Significant High Likely Negligible Low

PR-10 Dredge Acquisition Dredges for the project may not be available at all times. Unlikely Negligible Low Likely Significant High

PR-11

Oil and Gas facilities damage(storms, accidental releases)resulting in damage to barrierresources

Adverse impacts to existing resources (baseline conditions)

resulting from accidental releases, ongoing activities. Unlikely Marginal Low Unlikely Marginal Low

Review of USGS and MMS pipeline databases

revealed that there are no known pipelines within

the borrow area or fill sites. There is one oil/gas

structure to the north of the island and one pipelin

leading to this structure from offshore through

Whiskey Pass.

PR-13 Shore equipment mechanical issues

Dozers etc. may experience mechanical issues causing

downtime and reducing productivity. Unlikely Negligible Low Unlikely Negligible Low

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to be moved o

of an island during construction due to a hurricane event Likely Marginal Moderate Likely Marginal Moderate

10. Project Implications identifies whether or not the risk item affects project cost, project schedule, or both. The PDT is responsible for conducting studies for both Project Cost and for Project Schedule.11. Results of the risk identification process are studied and further developed by the Cost Engineer, then analyzed through the Monte Carlo Analysis Method for Cost (Contingency) and Schedule (Escalation) Growth.

Programmatic Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)Feature Code 30 - Planning, Engineering & DesignFeature Code 31 - Construction Management

*Likelihood, Impact, and Risk Level to be verified through market research and analysis (conducted by cost engineer).

Design

5. Risk Level is the resultant of Likelihood and ImpactLow, Moderate, or High. Refer to top matrix table.4. Impact is a measure of the event's effect on project objectives with relation to scope, cost, and/or schedule --Negligible, Marginal, Significant, Critical, or Crisis. Impacts on Project Cost may not be the same for impacts on Project Schedule.3. Likelihood is a measure of the probability of the event occurring --Very Unlikely, Unlikely, Moderately Likely, Likely, Very Likely. Likelihood of the event is the same for both Cost and Schedule.

1. Risk/Opportunity identified with reference to the Risk Identification Checklist and through deliberation and study of the PDT.2. Discussions and Concerns elaborates on Risk/Opportunity Events and includes any assumptions or findings (should contain information pertinent to eventual study and analysis of event's impact to project).

7. The responsibility or POC is the entity responsible as the Subject Matter Expert (SME) on the PDT for the identified risk or opportunity.8. Correlation recognizes those risk events that may be related to one another. Care should be given to ensure the risks are handled correctly without "9. Affected Project Component identifies the specific item of the project to which the risk directly or strongly correlates.

double counting."

6. Variance Distribution refers to the behavior of the individual risk item with respect to its potential effects on Project Cost and Schedule. For example, an item with clearly defined parameters and a solid most likely scenario would

Geotechnical & Survey


Risk No. Risk Event

Issues

(See Element Tabs for more detailed

descriptions) Likelihood Impact

Cost Risk

Level Distribution Low Likely High

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-$47,997 $0 $6,584

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to construction. Likely Marginal Moderate Triangular

-$522,459 $0 $629,590

PED-11

Geotechnical IssuesBeach/Dune Borrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. (Component 1 of 3

for Production Risk) Unlikely Significant Moderate Triangular

-$1,636,537 $0 $9,570,786

PED-12

Geotechnical Issues MarshBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. (Component 1 of 3

for Production Risk) Unlikely Significant Moderate Triangular

-$809,217 $0 $4,119,075

PR-2 Fuel Prices

Fluctuations in fuel costs could have an impact on

the project cost. Likely Significant High Triangular -$8,736,365 $0 $19,371,247

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open

Gulf especially during winter season and during a

severe tropical storm season. (Component 2 of 3 for

Production Risk) Likely Significant High Triangular

-$7,670,195 $0 $5,864,012

PR-5

Long Pipeline to Island forBeach Fill

Risk in Productivity/efficiency with long pipeline and

required number boosters. (Component 3 of 3 for

Production Risk) Likely Significant High Uniform

$0 $0 $8,522,783

PR-7

Bidder's Risk in VolatileMarket

Risk associated with bidders responding to volatile

markets with higher bid prices. Likely Significant High Triangular -$7,656,192 $0 $19,140,480

PR-8 Pipeline Steel Prices

Risks associated with changing steel prices

increasing the cost of pipe. Likely Significant High Triangular -$1,559,463 $0 $5,022,145

PR-14 Hurricane Demob/Re-mob

Dredge and Construction equipment may need to be

moved off of an island during construction due to a

hurricane event Likely Marginal Moderate Uniform

$0 $0 $1,887,415

All Other Project Cost(Placeholder) Placeholder to return to forecast value N/A N/A N/A

$90,089,312$90,089,312

Internal Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)External Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

LCA TBBSR - First Component of Construction - Initial Restoration Cost Risk Analysis Simulation

Crystal Ball Simulation

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihood of Occurrence

Risk Level


Risk No. Risk Event Issues Likelihood Impact

Schedule

Risk Level Distribution Low Likely High

PED-1 Marsh Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to or during construction. Likely Marginal Moderate Triangular

-0.08 0.00 0.07

PED-2 Beach Fill Design Quantities

Material volumes required under or over estimated

due to survey coverage / quality and or storms prior

to or during construction. Likely Significant High Triangular

-1.07 0.00 1.07

PED-11

Geotechnical IssuesBeach/Dune Borrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. (Component 1 of 3

for Production Risk) Unlikely Significant Moderate Triangular

-0.28 0.00 1.61

PED-12

Geotechnical Issues MarshBorrow Area

Geotechnical conditions in the borrow areas and

restoration areas may differ from data reviewed

during feasibility stage. Dredge volumes to meet

required fill volumes could differ. (Component 1 of 3

for Production Risk) Unlikely Significant Moderate Triangular

-0.10 0.00 0.19

PR-1

Sponsor's Ability to Fund ItsShare

Procuring funds from the non-federal sponsor has

been known to take long periods of time in the past. Likely Significant High Uniform

0.00 0.00 6.00

PR-3 Severe Weather Downtime

Risks associated with dredging operations in open

Gulf especially during winter season and during a

severe tropical storm season. (Component 2 of 3 for

Production Risk) Likely Significant High Triangular

-3.04 0.00 2.33

PR-4

Delays due to DesignModifications

Modifications to design could be required at time of

construction. Likely Significant High Uniform 0.00 0.00 2.00

PR-5

Long Pipeline to Island forBeach Fill

Risk in Productivity/efficiency with long pipeline and

required number boosters. (Component 3 of 3 for

Production Risk) Likely Significant High Uniform

0.00 0.00 2.97

PR-10 Dredge Acquisition

Dredges for the project may not be available at all

times. Likely Significant High Uniform 0.00 0.00 6.00

PR-14 Hurricane Demob/Re-mob

Construction equipment may need to be moved off

of an island during construction due to a hurricane

event Likely Marginal Moderate Uniform

0.00 0.00 0.74

All Other Project Time(Placeholder) Placeholder to return to forcast value

34.6034.60

Internal Risks (Internal Risk Items are those that are generated, caused, or controlled within the PDT's sphere of influence.)External Risks (External Risk Items are those that are generated, caused, or controlled exclusively outside the PDT's sphere of influence.)

LCA TBBSR - First Component of Construction - Initial Restoration Schedule Risk Analysis Simulation

Schedule Crystal Ball Simulation

Very

Likely Low Moderate High High High

Likely Low Moderate High High High

Unlikely Low Low Moderate Moderate High

Very

Unlikely Low Low Low Low High

Negligible Marginal Significant Critical Crisis

Impact or Consequence of Occurrence

Likelihood of Occurrence

Risk Level



LCA TERREBONNE BASIN

BARRIER SHORELINE

RESTORATION STUDY

ANNEX L-6

TOTAL PROJECT COST

SUMMARY FOR THE INITIAL

RESTORATIONS OF THE NER

PLAN AND FIRST COMPONENT

OF CONSTRUCTION



**** TOTAL PROJECT COST SUMMARY   Printed:9/9/2010

Page 1 of 1

PROJECT: Terrebonne Basin Barrier Shoreline Restoration - NER Plan DISTRICT: MVN - New Orleans PREPARED: 6/23/2010

LOCATION: Terrebonne Parish, Louisiana POC: CHIEF, COST ENGINEERINGThis Estimate reflects the scope and schedule in report; Integrated Feasibility Study and Environmental Impact Statement, June, 2010

Estimate Prepared: 23-Jun-10 Program Year (Budget EC): 2012

Effective Price Level: 1 OCT 09 Effective Price Level Date: 1 OCT 11 FULLY FUNDED PROJECT ESTIMATE

Spent Thru:

WBS Civil Works COST CNTG CNTG TOTAL ESC COST CNTG TOTAL 1-Oct-09 COST CNTG FULL

NUMBER Feature & Sub-Feature Description ($K) ($K) (%) ($K) (%) ($K) ($K) ($K) ($K) ($K) ($K) ($K)

A B C D E F G H I J K LM N O

06 FISH & WILDLIFE 5,821 Incl 5,821 Incl 5,821 5821 5,821 $5,82110 BREAKWATER & SEAWALLS 1,788 488 26% 2,276 2.5% 1,832 500 2333 1,959 535 $2,494

17 BEACH REPLENISHMENT 451,709 128,217 28% 579,926 2.5% 462,894 129,860 592754 482,057 136,822 $618,879

-- -

__________ __________ __________ ___________ _________________ __________ _ _________ _________ _______________

CONSTRUCTION ESTIMATE TOTALS: 459,318 128,705 588,023 2.2% 470,547 130,360 600907 489,838 137,357 $627,195

01 LANDS AND DAMAGES 532 160 30% 692 2.5% 545 164 709 550 165 $71530 PLANNING, ENGINEERING & DESIGN 22,673 6,435 28% 29,108 2.5% 23,234 6,594 29829 23,430 6,650 $30,08031 CONSTRUCTION MANAGEMENT 22,675 6,435 28% 29,110 2.5% 23,236 6,595 29831 24,179 6,862 $31,041

__________ __________ __________ ___________ _________________ __________ __________ _________ _________ _______________

PROJECT COST TOTALS: 505,198 141,735 28% 646,933 2.2% 517,564 143,713 661276.4 537,997 151,033 $689,031

CHIEF, COST ENGINEERING

ESTIMATED FEDERAL COST: 65.0% $447,870

PROJECT MANAGER, Fay Lachney ESTIMATED NON-FEDERAL COST: 35.0% $241,161CHIEF, REAL ESTATE ESTIMATED TOTAL PROJECT COST: $689,031CHIEF, PLANNINGCHIEF, ENGINEERINGCHIEF, OPERATIONSCHIEF, CONSTRUCTIONCHIEF, CONTRACTINGCHIEF, PM-PBCHIEF, DPM

Filename: TPCS_TBBSR_NER_08-03-2010 Final.xlsTPCS


** ** TOTAL PROJECT COST SUMMARY **** Printed:9/9/2010

Page 1 of 1

PROJECT: Terrebonne Basin Barrier Shoreline Restoration - First Component of Construction DISTRICT: MVN - New Orleans PREPARED: 6/23/2010LOCATION: Terrebonne Parish, Louisiana POC: CHIEF, COST ENGINEERINGThis Estimate reflects the scope and schedule in report; Integrated Feasibility Study and Environmental Impact Statement, June 2010

Program Year (Budget EC): 2012

Effective Price Level Date: 1 OCT 11 FULLY FUNDED PROJECT ESTIMATE

Spent Thru:

WBS Civil Works COST CNTG CNTG TOTAL ESC COST CNTG TOTAL 1-Oct-09 COST CNTG FULL

NUMBER Feature & Sub-Feature Description ($K) ($K) (%) ($K) (%) ($K) ($K) ($K) ($K) ($K) ($K) ($K)

A B C D E F GH I J K L M N O

06 FISH & WILDLIFE (ADAPTIVE MANAGEMENT) 5,821 Incl 5,821 Incl 5821.2 5821.2 5821.2 5821.217 BEACH REPLENISHMENT 76,562 21,208 28% 97,770 2.5% 78457.7 21732.8 100190.5 80838.5 22392.3 103230.8

- -- -- -

__________ __________ __________ _________ _________ __________ _ _________ _________ ____________

CONSTRUCTION ESTIMATE TOTALS: 82,383 21,208 103,591 2.3% 84278.9 21732.8 106011.7 86659.7 22392.3 109052.0

01 LANDS AND DAMAGES 50 15 30% 65 2.5% 51.2 15.4 66.6 51.7 15.5 67.130 PLANNING, ENGINEERING & DESIGN 3,830 1,061 28% 4,891 2.5% 3924.8 1087.2 5012.0 3949.1 1093.9 5042.931 CONSTRUCTION MANAGEMENT 3,828 1,060 28% 4,888 2.5% 3922.8 1086.6 5009.4 4039.1 1118.8 5158.0

__________ __________ __________ _________ _________ __________ __________ _________ _________ ____________

PROJECT COST TOTALS: 90,091.120 23,344 26% 113,435 2.3% 92177.8 23921.9 116099.7 94699.6 24620.5 119320.1

CHIEF, COST ENGINEERING

ESTIMATED FEDERAL COST: 77514

PROJECT MANAGER, Fay Lachney ESTIMATED NON-FEDERAL COST: 41806CHIEF, REAL ESTATE ESTIMATED TOTAL PROJECT COST: 119320CHIEF, PLANNINGCHIEF, ENGINEERINGCHIEF, OPERATIONSCHIEF, CONSTRUCTIONCHIEF, CONTRACTINGCHIEF, PM-PBCHIEF, DPM

Filename: TPCS_TBBSR_FCC_08-03-2010 Final.xlsTPCS


APPENDIX M

HAZARDOUS, TOXIC, AND

RADIOACTIVE WASTE REPORT



1

Volume IV

APPENDIX M:

Hazardous, Toxic, and Radioactive Waste Report

1.0 EXECUTIVE SUMMARY

The Coastal Protection and Restoration Authority (CPRA) retained the SJB Group, LLC (SJB) to

perform a HTRW Phase I Environmental Site Assessment (ESA) on an approximately 35 square

mile area in Terrebonne Parish, Louisiana. The area addressed in this investigation is the Study

Area for the Terrebonne Basin Barrier Shoreline Restoration (TBBSR) project which is located

within Terrebonne Basin in Terrebonne and Lafourche parishes. The TBBSR project is currently

one of six projects with Chief of Engineers Reports due to Congress no later than December 31,

2010.

The purpose of this Phase I ESA is to identify historical or overt physical evidence of current or

past activities or materials at the Site and its immediate vicinity which constitute "recognized

environmental conditions,"(RECs) defined by the ASTM Standard to be "the presence or likely

presence of any hazardous, toxic, and radioactive substances or petroleum products on a property

under conditions that indicate an existing release, a past release, or a material threat of a release . .

. into structures on the property or into the ground, groundwater, or surface water of the

property."

This Phase I ESA is consistent with the Scope of Work (SOW) provided by the Corps of

Engineers and protocols established in the American Society for Testing and Materials

publication "Standard Practice for Environmental Site Assessments: Phase I Environmental Site

Assessment Process for Forestland or Rural Property" (Designation E 2247-08, referred to as the

ASTM Standard) to provide "due diligence" for rural transactions. However, this report will

require a second site visit and interviews related to ASTM Standard to be conducted at a later

date that is closer to expected time of construction for the year 2012.

On November 20, 2008, SJB’s environmental specialists performed an aerial site reconnaissance

of the Study Area and a field visit on July 27 through 30 of 2009 at selected locations throughout

the Project Area. The Project Area is the Terrebonne Basin Barrier Shoreline and consists of

seven major barrier islands that include: East Timbalier Island, Timbalier Island, Wine Island,

East Island, Trinity Island, Whiskey Island, and Raccoon Island. Photographs were taken

documenting field observations and are included in this report.


2

SJB obtained historical documentation of the Site’s past uses and activities in order to identify

possible recognized environmental conditions. Sources of historical documentation for this report

included historical aerial photographs, topographic maps, and Environmental Database Report.

The historical aerial photographs and the topographic maps dating back to the late 1800’s were

obtained and reviewed to determine past land uses on and nearby the Site. The 1953 aerial

photograph showed oil and gas infrastructure developing along East Timbalier Island. Every year

after this date the oil and gas infrastructure has increased drastically expanding its limits to the

surrounding bays and islands. Several oil pits were observed on the aerial photographs and

topographic maps on or within the vicinity of East Timbalier Island (see photograph below).

Reminisce of these oil pits are still present today on East Timbalier Island. These pits were used

to dispose of liquids and sludge containing hazardous waste or petroleum products. The Sonris

database operated by LADNR was used to properly identify the location of these pits and who

was responsible for them.

SJB used an EDR Area Study that search all federal, state, local, and tribal records to help

identify any areas of concern that can be deemed a recognized environmental condition as defined

in ASTM standard E 2247-08. The database search revealed six reported sites. None of these pose

an environmental concern and are not considered a REC; however, they may be considered a

historical REC(s) due to the discharge of petroleum product to the affected environment. The

responsible operators have addressed all 6 ERNS (Emergency Response Notification System)

sites accordingly.

The site reconnaissance revealed two major oil and gas facilities located on Timbalier and East

Timbalier Islands and 12 pipelines that intersect or fall within the project work area. The two

major oil and gas facilities located on East Timbalier and Timbalier where not inspected and

interviews are schedule to be conducted at a later date closer to construction. The 12 oil and gas

pipelines that intersect or fall within the project work area currently have no visible

environmental concerns; however, if any of these were to experience a problem, numerous issues

could occur from a safety and environmental standpoint.

SJB has performed a Phase I Environmental Site Assessment in conformance with the scope and

limitations of the ASTM Standard E 1527-05 on Isle Dernieres and Timbalier Island chain

located within Terrebonne Basin in Terrebonne Parish, Louisiana, the Site. Any exceptions to or

deletions from this practice are described in section 2.4 of this report. The ERNS entries on the

Site thought to represent historical REC. After reviewing the monitoring reports, SJB found

indications of release of petroleum products for all 6 incidents. However, these releases have been

addressed in accordance of the EPA. Therefore, the ERNS entries are considered a historical

REC(s). SJB Group was unable to inspect the production facilities at this time. However, do to

the history of oil and gas development, oil pits, and spill incidents that have occurred on or near


3

East Timbalier Island, East Timbalier Island is currently a REC(s). SJB can not adequately

identify any other current recognized environmental conditions as defined in ASTM standard E

2247-08 on the remaining islands without proper investigation to their oil and gas facilities

located on or near them. A more in depth site visit and interviews with people knowledgeable of

the Study Area history will be conducted closer to the expected construction time.

Photograph of oil pit located on East Timbalier Island.