Merced Wild and Scenic River Comprehensive Management Plan / DEIS

APPENDIX O 

DRAFT WETLAND STATEMENT OF FINDINGS 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-1

APPENDIX O 

WETLAND STATEMENT OF FINDINGS 

FOR THE DRAFT MERCED WILD AND SCENIC RIVER 

COMPREHENSIVE MANAGEMENT PLAN 

This Wetlands Statement of Findings (WSOF) characterizes the wetland resources that occur within 

the project area for the Merced Wild and Scenic River Comprehensive Management Plan (Merced 

River Plan), describes the impacts the project will likely have on wetland resources, and documents the 

steps the National Park Service (NPS) will take to avoid, minimize, and offset these impacts. This 

Wetland Statement of Findings is included in this document for public review to meet the obligations 

of Executive Order 11990 (Protection of Wetlands), Director’s Order 77-1: Wetland Protection, and 

National Park Service Procedural Manual 77-1: Wetland Protection (2008). 

PURPOSE OF THIS STATEMENT OF FINDINGS 

Under Directors Order #77-1 for Wetland Protection, Part 2.5 states: 

Actions proposed by the NPS that have the potential to have adverse impacts on wetlands will 

be addressed in an Environmental Assessment (EA) or an Environmental Impact Statement 

(EIS). If the preferred alternative in an EA or EIS will result in adverse impacts on wetlands, a 

“Statement of Findings” documenting compliance with this Director’s Order (D.O.) and 

Procedural Manual #77-1 will be completed. Actions that may be excepted from the Statement 

of Findings requirement are identified in the Procedural Manual. 

In #77-1, Section 5.3.4 (3) states: 

“...A draft EIS that identifies a preferred alternative that will have adverse impacts on wetlands 

must be accompanied by a separately identifiable draft WSOF that explains why an alternative 

with such impacts was chosen and that meets the other requirements identified in 

Section 5.3.5 of these procedures.” 

The purpose of this Wetland Statement of Findings is to review the Merced River Plan in sufficient 

detail to: 

 Avoid, to the extent possible, the short-and long-term adverse impacts associated with the 

destruction or modification of wetlands and to avoid direct or indirect support of new 

construction in wetlands wherever there is a practicable alternative 

 Describe the effects on wetland values associated with the proposed action 

 Provide a thorough description and evaluation of mitigation measures developed to achieve 

compliance with Executive Order 11990 (Protection of Wetlands) and National Park Service 

Procedural Manual 77-1: Wetland Protection 

 Ensure “no net loss” of wetland functions or values 
APPENDIX O 

O-2 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

CHARACTERISTICS OF EXISTING WETLANDS 

Wetland Extent 

There are wetlands and/or riparian habitats in every segment of the Merced River corridor (figures O-1 

through O-8). Approximately 1,600 acres of wetland and/or riparian habitat occur within the Merced 

River corridor. Table O-1 provides a summary of the classes and areal extent of wetland and riparian 

habitats by corridor segment. Wetland data were obtained from site-specific wetland delineations, if 

available. National Wetland Inventory data (USFWS 1995), supplemented with data from the Yosemite 

Parkwide Vegetation Map (1997), were used to describe wetlands in the Merced River corridor in areas 

where delineation data were not available (site-specific wetland delineation data was only available for 

limited areas in Yosemite Valley). Data on riparian habitats was taken from the Merced River and 

Riparian Vegetation Assessment (Cardno ENTRIX 2011) for the river corridor through Yosemite Valley. 

Data from the Yosemite Parkwide Vegetation Map (1997) were used to describe riparian habitats outside 

of Yosemite Valley. This provides a conservative estimate of wetlands in the project area. 

TABLE O-1: CLASSES AND AREAL EXTENT OF WETLAND HABITATS IN THE MERCED RIVER CORRIDOR

Wetland Class Area per Segment (acres) 

Cowardin Class 1 2 3 4 5 6 7 8 

Riverine/Lacustrine 404.5 141.0 96.2 42.3 89.5 0.4 64.0 27.7 

Palustrine Emergent Wetland 

(wet meadows) 216.5 261.2 0 1.7 69.8 0 0 0 

Palustrine Forested Wetland 0 116.7 11.8 5.2 0.9 0 0 0 

Palustrine Scrub Shrub Wetland 10.0 13.7 12.0 4.6 3.3 0 2.5 0 

SOURCE: USFWS 1995; NPS 1997; NPS 2011 

The NPS classifies and maps wetland habitats using a system developed by wetland ecologists and an 

interagency team for the U.S. Fish and Wildlife Service (USFWS), which is often referred to as the 

Cowardin classification system (Cowardin et al. 1979). Wetlands, as defined by the USFWS, are 

transitional lands between terrestrial and aquatic systems where the water table is usually at or near the 

surface, or the land is covered by shallow water (Cowardin et al. 1979). For purposes of this 

classification, wetlands must have one or more of the following attributes: 

 The land predominantly supports hydrophytes, at least periodically. Hydrophytes are 

plants that grow in water or on a substrate that is at least periodically deficient in oxygen 

as a result of excessive water content. 

 The substrate is predominantly undrained hydric soils. Hydric soils are wet long enough 

to periodically produce anaerobic conditions. 

 The substrate is saturated with water or covered by shallow water at some time during the 

growing season of each year (Cowardin et al. 1979). 
IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

Washburn

Lake

Harriet

Lake

Edna

Lake

Merced River Watershed

South Fork

Merced River Watershed

Washburn

Stock Camp

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Doc Moyle's

Stock Camp Lyell Fork MercedRiver

Merced Peak Fork Merced River

Red Peak Fork Merced River

Triple Peak Fork Merced River

Washburn

Lake Meadow ! ! ! ! ! ! ! ! ! ! !

Doc Moyle's

Meadow- West ! ! ! ! ! ! ! ! !

Doc Moyle's

Meadow- East ! ! ! ! ! ! ! ! !

Triple Peak

Meadow- South ! ! ! ! ! ! ! ! ! !

Triple Peak

Meadow- North ! ! ! ! ! ! !

Red Peak

Meadow- South

! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Red Peak

Meadow- North ! ! ! ! ! ! ! ! ! !

Turner

Meadow- South

! ! ! ! ! ! ! ! ! ! ! !

Isberg

Pass

none

Lon g Creek

Gra y Peak Fork

Gra y C

Forester Creek

reek

Ot toway Creek

Red Creek

Red

Peak

Gray

Peak

Sadler

Merced Peak

Peak

Isberg

Peak

Rodgers

Peak

Ottoway

Peak

Electra

Peak

Mount

Clark

Long

Mountain

Foerster

Peak

Quartzite Peak

Triple

Divide Peak

Mount

Ansel Adams

IS Stock Campsite

Trail

Wild WSR Corridor Classification

Yosemite National Park Boundary

Lakes

Palustrine Emergent Wetland

Watershed Boundary

Yosemite

Wilderness

Ansel Adams

Wilderness

Meadow/Riparian Vegetation

Data Source: NPS, 1997

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-1

Segment 1 - Merced River Above Nevada Fall Wetlands

SOURCE: NPS, 1997, 2011

0 1

Miles

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment
np

np

np

#

!@ !@

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IS

IB

IB

Little Yosemite Valley

Merced

Lake

Lost Lake

Merced River

Merced Lake

High Sierra Camp

Echo Valley

Merced Lake

Ranger Station! ! ! ! ! !

Little Yosemite Valley

Ranger Station

Little Yosemite Valley

Backpackers Campground ! ! ! ! ! ! !

Bunnell

Cascade

Sunrise Creek

Merced Lake

Backpackers Campground ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! ! ! ! !

Moraine Dome

Backpackers

Campground ! ! ! ! ! ! ! ! !

Echo

Stock Camp

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Merced Lake

Administrative

Stock Camp ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Merced

Lake

MeadowEast

Merced Lake

Meadow- West

Merced Lake

Meadow- Shore ! ! ! ! ! ! ! ! ! ! ! ! !

! ! ! ! ! ! ! ! !

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Little Yosemite Valley

Meadow- West

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Little Yosemite Valley

Meadow- East ! ! ! ! ! ! ! ! ! ! ! ! !

JohnMui r Trail

Joh n Muir Trail

Ha lf Dome

Half

Dome

Liberty

Cap

Clouds

Rest

Moraine

Dome

Quarter

Domes

Bunnell

Point

Cascade

Cliffs

Bunnell

Cliff

Snow Creek Falls

Ech o Creek

Tenaya Creek

Snow

Creek

Gray Pe ak Fork

Recreational WSR Corridor Classification

Wild WSR Corridor Classification

Lake

Palustrine Emergent Wetland

Palustrine Scrub Shrub Wetland

Trail

Stream/River

# High Sierra Camp

!@ Ranger Station

np Backpackers Campground

IS Stock Campsite

IB Footbridge

Yosemite

Wilderness

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-2

Segment 1 - Little Yosemite Valley and

Merced Lake High Sierra Camp Wetlands

SOURCE: NPS, 1997, 2011

0 1

Miles

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment
) ) )

) ) )

) ) )

J

5

J

5

J

5

J

5

IB

IB

IB

IB

IB

IB

IB

IB

IB

IB

IB

IB

Lower

Yosemite Fall

Sentinel

Bridge

Merced River

North Pines

Campground

Royal Arch Creek

Indian Can

Ahwahnee Bike Path

Stoneman

Bridge

Lower Pines

Campground

Stoneman

Meadow

Lost Arrow Drive

Lost Arrow Drive

Lower Yosemite FallsTrail

Cooks Meadow

Boardwa kl

Housekeep ing BridgeTrail

Clark's

Bridge

Backpackers

Ahwahnee Campground

Bridge

Sugar Pine

Bridge

Valley Loop Trail

Camp 4

Tenaya Creek

Bridge

Yosemite

Lodge

Yosemite Village

The Ahwahnee

Hotel

Sentinel

Beach

Leidig

Meadow

Happy

Isles Bridge

Happy Isles

Nature Center

Staircase

Falls

Royal

Arch Cascade

Village Drive

Upper Pines

Campground

Housekeeping

Camp

Curry

Village

Superintendent's

Bridge

Swinging

Bridge

Stoneman

Boardwalk

Stock

Bridge

Housekeeping

Camp Bridge

SentinelBoardwalk

Happy

Isles Fen

Yosemite Lodge Road

Northside Drive

Mirror

Lake LoopTrail

Yellow Pine campground road

Yosemite Creek

Bridge

Northside Drive

Southside Drive

Oak Lane

Sentinel Crossover

Tecoya Road

Tenaya Way

Camp 6 Road

Cedar Lane

C astle Cliff Court Boulder Lane Ahwahnee Road

Cook's

Meadow

Ahwahnee

Meadow

Sentinel

Meadow

Four M ile Trail

ValleyLoop Trail

Valley LoopTrail

Happy IslesTrail

Union

Point

Glacier

Point

Royal

Arches

Washington

Column

Church Bowl

Picnic Area

Sentinel Beach

Picnic Area

Swinging Bridge

Picnic Area

Lower Yosemite

Fall Picnic Area

Recreational WSR Corridor Classification

Building

Campground

Palustrine Emergent Wetland

Palustrine Forested Wetland

Palustrine Scrub Shrub Wetland

Surfaced Area

Stream/River

Valley Loop Trail

Bike path

Boardwalk

Trail

IB Road bridge

IB Footbridge

) ) ) Waterfall

J

5 Picnic Area

Yosemite

Wilderness

SOURCE: NPS, 1997, 2006, 2010, 2011

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-3

Segment 2 - Yosemite Lodge,

Yosemite Village, and The Ahwahnee Wetlands

0 0.25

Miles
J

5

J

5

J

5

Fn

Fn

IB

IB

IB

Cathedral Beach

Sentinel

Beach

Bridalveil Trail

) )

)

Ribbon

Fall

Bridalveil

Fall

El Capitan

Bridge

Pohono

Bridge

UV140

UV41

Yellow

Pine

Taft Point

El

Capitan

Lowe

Brother

Leaning

Tower

Stanford

Point

Cathedral

Rocks

Cathedral

Spires

El Capitan

Meadow

Leidig

Meadow

Bridalveil

Meadow

Slaughterhouse

Meadow

Four Mile

Trailhead

Pohono

Trailhead

Pohono Trail

El Capitan Trail

Southside Drive

) ) )

) ) )

Ribbon Creek

Bridalveil Creek

Artist Creek

Eagle Creek

Meadow Brook

Sentinel Creek

Merced River

El Capitan

Picnic Area

Sentinel Beach

Picnic Area

Cathedral Beach

Picnic Area

Northside Drive

Wawona Road

El Portal Road

Yellow Pine

Campground Road

Old Big Oak Flat Road

Valley Loop Trai l

Old Wawon a Road

El Capitan Trail

Valley Loop Trail

Recreational WSR Corridor Classification

100 Year Flood Boundary

Palustrine Emergent Wetland

Palustrine Forested Wetland

Palustrine Scrub Shrub Wetland

Road

Stream/River

Valley Loop Trail

Trail

) ) )

Waterfall

Fn Trailhead

J

5 Picnic Area

Yosemite

Wilderness

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-4

Segment 2 - El Capitan Meadow,

Cathedral Beach, and Sentinel Beach Wetlands

SOURCE: NPS, 1997, 2010, 2011

0 0.25

Miles
! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Fn Fn

J5

J5

IB

) ) )

) ) ) ) ) )

) ) )

) ) )

) ) )

Foresta

å

Merced River

Arch Rock

Entrance Station

El Portal

Administrative Area

Old Big Oak

F lat Road Trail

Fore sta Road

Former Cascades

Diversion Dam Site

Cascades

Powerhouse

UV120

UV41

Yosemite National Park

Stanislaus National Forest

Elephant

Rock

Big Oak Flat Road

Old Wawona Road

Old Coulterville Road

New Big Oak Flat Road

Wawona Tunnel

Pohono Bridge

Pulpit

Rock

Turtleback

Dome

Wildcat

Falls

Foresta

Falls

The

Cascades

Silver

Strand Falls

Wawona Road

UV140

Le Conte Way

Glacier P oint Road

Dana Way

Ol d Coulterville Road

O ld Big O ak Flat R oad

PohonoTrail

PohonoTrail

Old Big Oak Flat

Trailhead Pohono

Trailhead

Grouse Creek

Artist Creek

Meadow Brook

Avalanche Creek Indian Creek

Cascade Creek

Cran e Creek

Arch Rock

Picnic Area

Cascades

Picnic Area

Yosemite

Wilderness

Tunnel View

Scenic WSR Corridor Classification

Recreational WSR Corridor Classification

Palustrine Emergent Wetland

Palustrine Forested Wetland

Palustrine Scrub Shrub Wetland

) ) ) Waterfall

IB Road bridge

J5 Picnic Area

Fn Trailhead

Highway

Road

Trail

Stream/River

0 0.25 0.5

Miles

SOURCE: NPS, 1997, 2010, 2011

Segment Map Area

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-5

Segment 3 - Merced Gorge Wetlands
IB

IB

IB

Henness Branch

Crane Creek

Merc ed R iver

Foresta Road

UV140

Murchison

Structures

Yosemite View

Lodge

Trailer Court

El PortalTrailer Court Road

El Portal Wastewater 

Treatment Plant

Indian Creek

Foresta

Bridge

Highway 140

Bridge

El Portal

Road

Crane Creek

Bridge

Abbieville

Yosemite National Park

Sierra National Forest Stanislaus National Forest

El Portal Administrative Area

Foresta Road

Middle Road

Rancheria Flat Road

Cold Canyon Rd

Crane Creek Road

Barium Mine Road

Incline Road

River Road

ChapelLane

Eagle Peak Road

Red Bud Lane

Boulder Lane

Buckeye Court

Rocky Road

LarkspurWay

Rancheria Flat Court

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IB

Fn

IS

å

Edna

Lake

Segment 5: South Fork

Merced River above Wawona ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Chain

Lakes

Breeze

Lake

Segment 6:

Wawona Impoundment

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Moraine

Meadows

Mariposa

Grove Trailhead

UV41

Chilnualna

Falls Trailhead

Chilnualna Falls Trail

Fern and ez Pass

Quartz Mountain

Trailhead Sky R a nch Road

Gr iz z ly Creek

Wawona

winging Bridge

Ostrander

Lake

Hoover

Lakes

Lady

Lake

Lillian

Lake

Flat

Lake

Chiquito

Lake

Star

Lakes

Horsethief

Stock Camp

Yosemite National Park

Crescent Creek

Ottoway Creek

Shirl ey Creek

Chiquito Creek

Iron Creek Trail

Redtop

Sing

Peak

Gale

Peak

Wawona

Dome

Merced Peak

Madera

Peak

Wawona

Point

Ottoway Peak

Mount

Bruce

Mount

Raymond

Quartz

Mountain

Moraine Mountain

Buena

Vista Peak

Triple

Divide Peak

orest Drive

ChilnualnaCreek

Iron C r eek

Givens Creek

Buck Cree k

South Fork Merced River

JohnsonCreek

Crescent Cr eek

Buena Vista Creek

B r idalve i l Creek

Portuguese Creek

Rainier Creek

Madera Creek

F ernandez Creek

Shirley Creek

Wild WSR Corridor Classification

Recreational WSR Corridor Classification

Yosemite National Park Boundary

Lake

Palustrine Emergent Wetland

Palustrine Forested Wetland

Palustrine Scrub Shrub Wetland

Trail

Stream/River

Road

Fn Trailhead

Yosemite

Wilderness

Ansel Adams

Wilderness

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

SOURCE: NPS, 1997, 2011 Merced River Comprehensive Management Plan and EIS . 210436

Figure O-7

Segment 5 - South Fork Merced

River Above Wawona Wetlands

0 1

Miles
Fn

Fn

Fn

Fn

Fn

IB IB

IB

IG

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Segment 8: South Fork Merced River

below Wawona

Wawona

Campground

South Fork of the Merced River

Chilnualna Creek

Rush Creek

! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !

Segment 7: Wawona

Big Creek

Segment 6:

Wawona Impoundment ! ! ! ! ! ! ! ! ! ! ! ! ! !

Segment 5: South Fork

Merced River

above Wawona ! ! ! ! ! ! ! ! ! ! ! !

Wawona

Bridge

Wawona

Swinging Bridge

Wawona Swinging Bridge Trail

Chilnualna Falls Road

Koon Hollar

Wawona Campground Road

Alder

Creek Trailhead

Bishop

Creek Trailhead

Chilnualna Falls Road

Bills Hill Road

R i v e r Street

Iron Creek

Alder Creek

Mosquito Creek

Alder C reek Trail

UV41

Yosemite National Park

Sierra National Forest

Wawona Road

Wawon a Meadow Loop

Spelt Road

East Bruce Lane

English Lane

Fir Street

Larkspur Lane

Forest Drive

Gordon Way

Wawona

Golf Course

Wawona

Covered Bridge

Alder

Creek Trailhead

Wawona

Point Trailhead

Chilnualna Falls

Trailhead

Campground

Building

Palustrine Scrub Shrub Wetland

Yosemite National Park Boundary

Fn Trailhead

IB Road bridge

IB Footbridge

IB Covered Bridge

IG Golfcourse

Highway 41

Road

Stream/River

Trail

Yosemite

Wilderness

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-8

Segments 6,7, and 8 - Wawona Impoundment,

Wawona, and the South Fork Merced

River Below Wawona Wetlands

SOURCE: NPS, 1997, 2011

0 0.5

Miles

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-11

The U.S. Army Corps of Engineers (Corps) uses three wetland parameters to define wetlands for 

regulatory purposes: hydrophytic vegetation, hydric soil, and wetland hydrology. When all three 

parameters are present, the wetland is considered a jurisdictional wetland. The Cowardin system 

defines more habitat types as wetlands than does the Corps definition as it recognizes many 

unvegetated sites (e.g., mudflats, stream shallows, saline lakeshores, playas) or sites lacking soil (e.g., 

rocky shores, gravel beaches) as wetland habitats if wetland hydrology is present. The reason these 

sites lack hydrophytic vegetation and/or hydric soil is due to natural chemical or physical factors. 

Although the Corps does not consider these sites to be wetlands, they are still subject to regulations 

under section 404 of the CWA as other waters of the United States. For purposes of this document, 

both Cowardin wetlands and waters of the United States as defined by the Corps are referred to as 

wetlands. 

Wetland Characteristics 

Specific wetland classes identified within the Merced River corridor include riverine (rivers, creeks, 

and streams), palustrine (shallow ponds, riparian wetlands, wet meadows, marshes), and lacustrine 

(lakes and ponds). Using the Cowardin classification system, specific wetland and deepwater classes 

within the Merced River corridor include: 

 Riverine upper perennial – main channels of the Merced River and the South Fork Merced 

River (may be wetland or deepwater depending on depth) 

 Riverine intermittent – intermittent tributaries to the Merced River and South Fork Merced 

River (wetlands) 

 Palustrine emergent – emergent wetland habitat (marsh, meadow) along the Merced River and 

South Fork Merced River subject to various flooding regimes 

 Palustrine forested – riparian forest wetland habitat along the Merced River and South Fork 

Merced River subject to various flooding regimes 

 Palustrine scrub shrub – riparian scrub (e.g., willow) wetland habitat along the Merced River 

and South Fork Merced River and its tributaries subject to various flooding regimes 

 Lacustrine littoral – shallow lake margins that are less than 2 meters deep at low water and have 

less than 30% vegetation coverLacustrine limnetic – portions of lakes that are more than 

2 meters deep at low water (e.g., Merced Lake, Washburn Lake) along the Merced River 

(deepwater habitat) 

The following discussion provides general descriptions for each wetland class identified within the 

Merced River ecosystem. 

Riverine Upper Perennial. Riverine upper perennial habitat within the corridor includes the open and 

flowing water of the Merced River and the South Fork Merced River. It is the permanently flooded rock-, 

cobble-, or sand-bottom channel with little to no in-stream vegetation. Occasional sandbars form within 

and at the channel edge and typically support willows and emergent (grasses and herbs) vegetation. Based 

on the NPS guidelines, the majority of the main stem of the Merced River and the South Fork Merced 

River would be classified as riverine upper perennial wetland. Channel portions that lie at a depth of 2 
APPENDIX O 

O-12 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

meters below low water would be considered deep water. The main channel of the Merced River and the 

South Fork Merced River would likely be considered as jurisdictional by the Corps under section 404 of 

the CWA, not as wetlands but as other waters of the United States. 

Riverine Intermittent. Numerous riverine intermittent drainages (other waters of the United States) are 

tributary to the main stem Merced River and the South Fork Merced River. Almost all riverine 

intermittent drainages within the river corridor are classified as Cowardin wetlands and waters of the 

United States. These drainages often have a nonsoil substrate that is saturated and/or covered by shallow 

water at some time during the growing season. These wetlands are typically narrow and encompass the 

lowest portion of creekbeds. Very little wetland vegetation is found in these areas because of the 

intermittent nature of the flows within the drainage channels. All aboveground drainages within the river 

corridor are subject to the NPS protection policies under Executive Order 11990. These drainages are 

classified as other waters of the United States and would be subject to sections 401 and 404 of the CWA. 

Palustrine Emergent. Palustrine emergent wetland habitat includes portions of alpine, subalpine, and 

montane meadows and seeps. These wetland soils are generally deep and peaty, remaining saturated 

year-round or on a seasonal basis. Vegetation is dominated by grasses, sedges, rushes, and perennial 

herbs. The meadow wetlands in Yosemite National Park play a particularly critical role in the Merced 

River ecosystem. High spring flows create wet areas in side channels, low-lying wetlands, meadows, 

and cutoff channels. These areas support the concentration of organic matter, nutrients, 

microorganisms, and aquatic invertebrates throughout the relatively dry summer. When the flush of 

winter or spring flooding occurs, this stored aquatic biomass is washed into the main river channel, 

forming the base of the aquatic food chain. Examples of palustrine wetlands include portions of 

Cook’s Meadow and meadows adjacent to Washburn and Merced Lakes. These meadow portions are 

considered wetlands under the Cowardin system, and portions of meadows may also meet the Corps’ 

wetland criteria. Delineated palustrine emergent wetlands are subject to the NPS protection policies 

under Executive Order 11990 and section 404 of the CWA. 

Palustrine Forested. Palustrine forested wetlands are the riparian forest habitats along the main stem 

of the Merced River and South Fork Merced River that are regularly inundated by normal high-water 

or flood flows. Palustrine forests within the upper reaches of the main stem of the Merced River and 

South Fork Merced River consist mainly of evergreen pines and firs, with occasional aspens. In 

Yosemite Valley, where the river is broad, shallow, and slow-moving, deciduous cottonwoods, 

willows, and alders dominate the riparian corridor. Substrate under the palustrine forest community 

varies from rock, gravel, sand, clays, loams, and mud. These areas are classified as either wetland or 

other waters of the United States by the Corps, depending on site-specific vegetation, soils, and 

hydrologic conditions, and would be subject to section 401 and/or 404 of the CWA. 

Palustrine Scrub Shrub. This habitat type occurs sporadically along the banks of the main stem of the 

Merced River, the South Fork Merced River, and at lake margins. It is regularly inundated by normal 

high-water or flood flows. This habitat is dominated by various willows and often intergrades with 

meadow (palustrine emergent) and riparian (palustrine forest) communities. These communities are 

typically considered wetlands under the Cowardin system, would be subject to the NPS protection 

policies under Executive Order 11990, and typically meet the Corps’ wetland criteria. These areas may 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-13

meet the Corps’ criteria of a wetland or other waters of the United States, depending on site-specific 

vegetation, soils, and hydrologic conditions, and may be subject to sections 401 and/or 404 of the CWA. 

Lacustrine Littoral. Lacustrine littoral includes all wetland habitats within a lacustrine system. This 

classification extends from the shoreward boundary of the system to a depth of 2 meters below low 

water or to the maximum extent of emergent vegetation. These habitats are adjacent to deep-water 

lakes and reservoirs along the Merced River. These communities are typically considered wetlands 

under the Cowardin system, would be subject to the NPS protection policies under Executive Order 

11990, and may meet the Corps’ wetland criteria, depending on site-specific vegetation, soils, and 

hydrologic conditions, and may be subject to sections 401 and/or 404 of the CWA. 

Lacustrine Limnetic. Lacustrine limnetic refers to deepwater lakes and reservoirs, such as Merced 

and Washburn lakes. Both lakes were formed along the Merced River by glacial activity. In-lake 

vegetation is typically limited to rooted aquatic grasses, floating vascular plants, and algae. Meadow 

(palustrine emergent) and riparian (palustrine forest and palustrine scrub shrub) communities 

generally border lake margins. 

These lakes provide important habitat for fish, amphibians, reptiles, and other aquatic species. 

Substrate varies from rock, gravel, sand, and mud. Lacustrine limnetic (deepwater lakes and ponds) are 

classified as deepwater habitat based on the Cowardin system. These areas are typically classified as 

other waters of the United States by the Corps and would be subject to regulation under section 404 of 

the CWA. 

Segment Descriptions 

The characteristics of the individual segments within the Merced River corridor, including vegetation, 

connectivity and integrity have been summarized from the Draft EIS below. 

Segment 1: Merced River Above Nevada Fall 

Numerous small wetland meadows and adjacent riparian habitat are present in the upper Wilderness 

reaches of the Merced River corridor above Nevada Fall. These high-elevation meadows typically occur 

on fine-textured, permanently to semi-permanently wet soils generally associated with perennial streams, 

seeps, lake margins, or depressions. Vegetation consists of low-growing, native, tussock-forming grasses, 

sedges, rushes, and perennial herbs. Merced and Washburn lakes were formed where the Merced River 

canyon was carved by glaciers. In-lake vegetation is typically limited to rooted aquatic grasses, floating 

vascular plants, and algae. Meadow communities border lake margins. These wetland plant communities 

are hydrologically driven by the groundwater and flooding regime of the Merced River. 

Much of the Merced River above Nevada Fall is bordered by a narrow riparian zone influenced by 

stream gradient, slope, sedimentation, and aspect. High-elevation tributaries to the Merced River are 

sparsely vegetated with scattered patches of alpine riparian scrub and alpine willow thickets. As the 

river descends and the gradient becomes gentler, lodgepole pines, aspens (Populus tremuloides), 

willows (Salix spp.), and alders (Alnus spp.) become more prevalent. Riparian communities of the 

upper Merced River are generally intact, except in a few locations where human use is intense. 
APPENDIX O 

O-14 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

Segment 2: Yosemite Valley 

Wetlands in Yosemite Valley are formed in low-gradient land adjacent to the Merced River, its 

tributaries, or other bodies of water that are, at least periodically, influenced by flooding or high water 

tables. Wetlands within Yosemite Valley have undergone systematic alteration since the middle of the 

19th century as they were grazed, farmed, and used as recreational sites and corridors for travel. Other 

alterations that took place in the early 20th century include drainage ditches that were constructed to 

dewater wet meadows to reduce mosquito breeding areas and provide open land for grazing and 

agriculture. Many of these drainage ditches have not been filled in and continue to dewater wet 

meadows in Yosemite Valley. Road construction has involved drainage measures and diversion of 

surface water adjacent to many of the valley’s wetlands. This wetland complex was formerly much 

more interrelated and contiguous but has been fragmented by roads, trails, and infrastructure. 

Riparian zones in Yosemite Valley extend outward from bank edges of the Merced River and its 

tributaries into adjacent meadow and forest communities. Situated at the interface between terrestrial 

and aquatic ecosystems, the riparian zone acts to buffer hydrology and erosional cycles, control and 

regulate biogeochemical cycles of nitrogen and other key nutrients, limit fire movements, and create 

unique microclimates for animal species. Riparian zones in Yosemite Valley are characterized by 

broadleaf deciduous trees, such as white alder (Alnus rhombifolia), black cottonwood (Populus 

trichocarpa), big-leaf maple (Acer macrophyllum), white fir, and willow species. Riparian vegetation is 

regularly disturbed by the deposition and removal of soil and the force of floodwaters. Plants in this 

zone colonize newly formed river-edge deposits readily. The distribution of riparian communities 

varies with soil saturation and frequency of disturbance. 

Primary stressors on the condition of riparian habitats along the Merced River are related to high 

recreation use, channel stabilization measures, and dewatering due to infrastructure. Water, 

wastewater and electric lines and other utility infrastructure are located throughout Yosemite Valley 

(Segment 2), including some within wetland areas. Restoration efforts (prescribed burns, invasive plant 

eradication, fencing, and increasing inundation levels through restoration of natural drainage patterns, 

among others) have generally been successful at improving the overall condition of the Valley’s 

riparian communities. However, certain riparian areas within the Valley continue to experience 

vegetation trampling and bank erosion from heavy recreation use. Additional riparian vegetation 

impacts are occurring along reaches that have been armored by revetments or other defensive 

structures for the protection of structures (i.e., bridges). 

Segment 3 and 4: Merced Gorge and El Portal 

As the Merced River cascades through the gorge, the channel gradient and bank slopes steepen, the 

river channel narrows, and the floodplains become considerably smaller than those of the Yosemite 

Valley. The steep gradient, combined with the boulders and cobbles of the riverbed and bank, forms a 

series of continuous rapids between Yosemite Valley and El Portal. The Merced River gorge is lined 

with a narrow band of riparian vegetation along the river course. 

Flooding has been an important aspect of the development of riparian communities along the Merced 

River and its tributaries that intersect drier adjacent vegetation types of El Portal. Localized seasonal 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-15

flooding creates debris dams in tributary channels, thus furthering a diversity of scour and 

depositional soils for riparian species. On the Merced River, natural flooding and vegetative patterns 

are influenced by the construction of levees and application of riprap to confine the river. These 

structures have destroyed riparian vegetation and have limited their reestablishment in some places. 

In the El Portal area, riparian communities occur along tributaries of the Merced River, on flat 

topographical shaded terraces above the river, in backwater channels, and in areas where runoff from 

upland sites collects in natural depressions. Native Oregon ash (Fraximus latifolia), willow, and 

Fremont cottonwood (Populus fremontii ssp. fremontii) trees occur in the wetter areas, as well as 

orchard components in some locations. Foothill pines and valley oaks tend to dominate the drier 

terraces adjacent to riparian sites. 

Oxbows, river terraces, and seasonal river channels were a part of the riparian wetlands of the area, but 

have been affected by early to mid-20th century development in what is now the El Portal 

Administrative Site. Many of the sites that would be characterized as palustrine have been affected to 

some degree. The remaining wetland areas that appear on the USFWS (1995) wetland inventory are 

riverine perennial wetlands and are in proximity to the Merced River or other stream drainages. Direct 

human intrusion into the riparian areas of this river zone, especially to the south, is minimal because of 

the topography and difficulty of access. 

Segment 5 and 8: South Fork Merced River Above and Below Wawona 

From its headwaters, the South Fork Merced River flows west at a relatively consistent but steep 

gradient through a glaciated alpine environment and then enters a V-shaped, unglaciated river valley. 

The upper South Fork supports limited riparian vegetation, primarily due to steep topography and 

high-velocity flows. The steep gradients along the upper and lower South Fork Merced River are not 

conducive to the establishment of an extensive riparian zone. Typical riparian species — willow, alder, 

aspen, and maple — are restricted to a narrow fringe along the river. High-elevation tributaries to the 

South Fork Merced River are either unvegetated, high-velocity, and rocky in nature or are only 

sparsely vegetated. Subalpine meadows along the South Fork Merced River are similar in composition 

to those described for the upper main stem of the Merced River. Vegetation in alpine lakes is typically 

limited to rooted aquatic grasses, floating vascular plants, and algae. The upper South Fork is generally 

pristine and remains virtually undisturbed by human-related effects. The steep gradient below 

Wawona along the South Fork prevents the establishment of an extensive riparian zone. The limited 

riparian vegetation along the lower reach remains relatively untouched by human intrusion. 

Segment 6 and 7: Wawona 

In the Wawona area, the Merced River meanders through a large floodplain meadow (part of a deep 

alluvial valley) and has substantial gravel bars within the channel. As the river descends and the gradient 

becomes gentler, riparian vegetation (willows and alders) becomes more prevalent. Willows often 

colonize sandbars that are deposited at the margins of or within the river channel. In this area, the riparian 

corridor resembles the riparian corridor seen along the Merced River as it flows through Yosemite Valley. 

As with certain points within Yosemite Valley, trampling of riparian vegetation and associated erosion 

does occur in this area, resulting from heavy use in the vicinity of the Wawona Campground. 
APPENDIX O 

O-16 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

THE PREFERRED ACTION IN THE MERCED RIVER PLAN 

The Preferred Alternative of the Merced River Plan/DEIS would include significant restoration within 

100 feet of the river and in meadow and riparian areas, maintaining daily visitation in Yosemite Valley 

to accommodate the same peak levels observed in recent years, reducing unnecessary facilities and 

services, and converting facilities from administrative use to public use where feasible. Alternative 5 

envisions broad ecological restoration goals, including essential restoration of riverbanks and meadow 

and riparian habitat. Proposed restoration actions are feasible and achievable, and leverage engineering 

and design features to enhance meadow and floodplain connectivity and free-flowing condition. Much 

of the development footprint within 100 feet of the river is removed corridorwide. Targeted 

infrastructure within the bed and banks of the river is removed, and those areas ecologically restored. 

Actions to manage visitor use and facilities under Alternative 5, specifically those concerning vehicle 

access and overnight accommodations, would result in a 2% increase in lodging accommodations. The 

campsite inventory would increase by 29% in the Merced River corridor and 37% in Yosemite Valley. 

All campsites within 100 feet of the river would be removed. Campsite losses would be offset with the 

addition of new camping adjacent to Upper Pines Campground and east of the Camp 4 Campground, 

as well as new sites west of Backpackers Campground, in the former Upper River Campground area, 

and east of El Capitan Picnic Area at Eagle Creek. Under Alternative 5, there would be a net increase of 

13% in Yosemite Valley overnight use. This would largely result from the increase in units at Curry 

Village. Management actions related to lodging would focus on removing lodging from the ordinary 

high water mark and Housekeeping Camp, and slightly reducing lodging in wilderness. Tent cabins in 

the Boys Town area would be replaced with hard-sided lodging in Curry Village to increase the 

availability of year-round accommodations. 

Alternative 5 would restore approximately 203 acres of vegetation, including 40.52 acres of wetlands, 

as a result of actions common to Alternatives 2-6 in conjunction with actions specific to Alternative 5. 

Actions to manage visitor use and facilities would result in the loss of approximately 36.89 acres of 

vegetation and 2.67 acres of wetlands as a result of actions specific to Alternative 5. 

For a detailed description of the Preferred Alternative, refer to Vol. I, Chapter 8 of the Draft Merced 

River Plan/DEIS (NPS 2012). 

ENVIRONMENTAL CONSEQUENCES OF THE PROPOSED ACTION ON 

WETLANDS 

The purpose of the Merced River Plan is to provide a comprehensive management plan for the 

protection of the Merced River’s free-flowing condition, water quality, and the values that make the 

river worthy of designation. The preferred alternative, Alternative 5: Enhanced Visitor Experiences 

and Essential Riverbank Restoration, includes management action in Segments 1-8 of the Merced 

River corridor which would affect wetlands. Though the overall impact would be long-term and 

beneficial, some localized actions would have an adverse impact on wetlands. A more detailed 

description of Alternative 5 is included in the “Alternatives” (Chapter 8) of the Merced River 

Plan/DEIS. The following is a summary of actions that could have an effect on wetlands. A summary of 

cumulative impacts follows. 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-17

Proposed New Development in the Preferred Alternative of the Merced River 

Plan/DEIS 

Segment 2: Yosemite Valley 

Construction activities associated with new development in Segment 2 would result in direct, 

temporary and permanent losses of native vegetation as well as the redevelopment of existing 

developed areas. Outside of previously developed areas, the majority of new development in Segment 

2 would occur in upland habitats and would not directly impact wetlands. However, direct impacts to 

wetlands would occur at Curry Village, Yosemite Village Day-use Parking Area, and Yosemite Lodge 

and Camp 4 (see figures O-9 through O-12 and table O-2). Construction activities at Curry Village 

would result in direct, permanent losses of federally protected wetlands. Impacts to wetlands would 

occur in palustrine emergent wetlands associated with Stoneman Meadow and intermittent channels 

flowing through the area. Approximately 0.06 acres of potentially jurisdictional wetland features would 

be directly and permanently impacted by the resigned overnight visitor accommodations at Boys Town 

in Curry Village under Alternative 5. Construction activities at the Yosemite Village Day-use Parking 

Area would result in direct, temporary and permanent losses of federally protected wetlands. Impacts 

to wetlands would occur in palustrine emergent wetlands located adjacent to the Northside Drive and 

Sentinel Crossover intersection, palustrine forested wetlands associated with the Merced River, and 

intermittent channels flowing through the area. Approximately 2.56 acres of potentially jurisdictional 

wetland features would be directly and permanently impacted by the redesign of the Yosemite Village 

Day-use Parking Area and associated intersection and roadway improvements by the proposed actions 

under Alternative 5. Construction activities at Yosemite Lodge and Camp 4 would result in direct, 

permanent losses of federally protected wetlands. Impacts to wetlands would occur in palustrine 

emergent wetlands and along the Merced River and in intermittent channels flowing through the area. 

Approximately 0.05 acres of potentially jurisdictional wetland features would be directly and 

permanently impacted by the Yosemite Lodge Parking Area and replacement of temporary housing at 

Highland Court with new permanent housing under Alternative 5. 

TABLE O-2: SUMMARY OF WETLAND IMPACTS IN SEGMENT 2 – ALTERNATIVE 5 

Wetland Type Curry Village Camp 6 and 

Yosemite Village

Yosemite Lodge 

and Camp 4 Total 

Palustrine Emergent 0.04 1.21 0.01 1.26 

Palustrine Forested 0 0.96 0 0.96 

Riverine Intermittent 0.02 0.39 0.03 0.44 

Riverine Perennial 0 0 0.01 0.01 

SOURCE: NPS 2012c 

Losses to these wetlands would occur through site clearing, filling, grading, and subsequent 

development. Wetlands that cannot be avoided and would be permanently filled must be compensated 

to result in “no net loss” of wetlands. Adherence to proposed best management practices and 
APPENDIX O 

O-18 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

mitigation measures, and avoidance of wetlands during construction where possible, would reduce 

direct impacts to wetlands to local, long-term, moderate and adverse. 

Construction activities associated with new development in Segment 2 may also generate indirect 

impacts to wetlands. Construction would involve activities such as grading and excavation that would 

generate loose, erodible soils. These activities could result in substantial erosion off-site to adjacent 

wetlands, resulting in decreases in water quality due to sedimentation. Other indirect impacts include 

potential modifications to flow, circulation, hydroperiod, or other aspects of the hydrologic regime; 

human intrusion into wetlands; and temporary impacts to wetlands. However, post-construction, 

temporarily impacted areas would be restored. Adherence to proposed best management practices 

and mitigation measures, and avoidance of wetlands during construction where possible, would 

reduce indirect impacts to wetlands to local, long-term, minor and adverse. 

Segment 4: El Portal 

Construction activities associated with new development in Segment 4 would result in direct, 

temporary and permanent losses of native vegetation as well as the redevelopment of existing 

developed areas. Outside of previously developed areas, new development in Segment 4 would occur 

in upland habitats and would not directly impact wetlands. However, construction activities associated 

with the El Portal Remote Visitor Parking, the removal of Odger’s Fuel Storage Facility, and 

restoration of the Greenemeyer Sandpit may generate indirect impacts to wetlands. Construction 

would involve activities such as grading, excavation, and demolition that would generate loose, 

erodible soils. These activities could result in substantial erosion off-site to adjacent wetlands, resulting 

in decreases in water quality due to sedimentation. Other indirect impacts include potential 

modifications to flow, circulation, hydroperiod, or other aspects of the hydrologic regime; human 

intrusion into wetlands; and temporary impacts to wetlands. However, post-construction, temporarily 

impacted areas would be restored. Adherence to proposed best management practices and mitigation 

measures, and avoidance of wetlands during construction where possible, would reduce indirect 

impacts to wetlands to local, long-term, minor and adverse. 

Segment 7: Wawona 

Construction activities associated with new development in Segment 7 would result in direct, 

temporary and permanent losses of native vegetation as well as the redevelopment of existing 

developed areas. Outside of previously developed areas, new development in Segment 7 would occur 

in upland habitats and would not directly impact wetlands. However, construction activities associated 

with new development in Segment 7 may generate indirect impacts to channels and waters of the US. 

Construction would involve activities such as grading and excavation that would generate loose, 

erodible soils. These activities could result in substantial erosion off-site to adjacent wetlands, resulting 

in decreases in water quality due to sedimentation. Other indirect impacts include potential 

modifications to flow, circulation, hydroperiod, or other aspects of the hydrologic regime; human 

intrusion into wetlands; and temporary impacts to wetlands. However, post-construction, temporarily 

impacted areas would be restored. Adherence to proposed best management practices and mitigation 

measures, and avoidance of wetlands during construction where possible, would reduce indirect 

impacts to wetlands to local, long-term, minor and adverse. 
) ) )

) ) )

) ) )

IB

IB

IB

IB

IB

IB

IB

IB

IB

IB

IB

IB

Lower

Yosemite Fall

Sentinel

Bridge

Merced River

North Pines

Campground

Royal Arch Creek

Indian Can

Ahwahnee Bike Path

Stoneman

Bridge

Lower Pines

Campground

Stoneman

Meadow

Lost Arrow Drive

Lower Yosemite FallsTrail

Cooks Meadow

Boardwa kl

Clark's

Bridge

Backpackers

Campground Ahwahnee

Bridge

Sugar Pine

Bridge

Valley Loop Trail

Camp 4

Tenaya Creek

Bridge

Yosemite

Lodge

Yosemite Village

The Ahwahnee

Hotel

Sentinel

Beach

Leidig

Meadow

Happy

Isles Bridge

Happy Isles

Nature Center

Staircase

Falls

Royal

Arch Cascade

Village Drive

Upper Pines

Campground

Housekeeping

Camp

Curry

Village

Superintendent's

Bridge

Swinging

Bridge

Stoneman

Boardwalk

Stock

Bridge

Housekeeping

Camp Bridge

SentinelBoardwalk

Happy

Isles Fen

Yosemite Lodge Road

Northside Drive

Mirror

Lake LoopTrail

Yosemite Creek

Bridge

Northside Drive

Southside Drive

Oak Lane

Sentinel Crossover

Tecoya Road

Tenaya Way

Cedar Lane

C astle Cliff Court Boulder Lane Ahwahnee Road

Cook's

Meadow

Ahwahnee

Meadow

Sentinel

Meadow

Four M ile Trail

ValleyLoop Trail

Valley LoopTrail

Happy IslesTrail

Union

Point

Glacier

Point

Royal

Arches

Washington

Column

Facilities Impact Area

Impacted Wetlands/Waters of the U.S. - 2.67 acres

Recreational WSR Corridor Classification

Surfaced Area

Building

Campground

Wetlands

Palustrine Emergent Wetland - 1.26 acres impacted

Palustrine Forested Wetland - 0.96 acres impacted

Palustrine Scrub Shrub Wetland

Other Waters of the U.S.

Riverine Intermittent - .44 acres impacted

Riverine Perennial - 0.01 acres impacted

Restoration

Black Oak Restoration

Floodplain & Riparian Restoration

Meadow Restoration

Potential Meadow Restoration

Riparian Restoration

Riparian and Floodplain

Riparian restoration

Stream/River

Valley Loop Trail

Bike path

Boardwalk

Trail

IB Road bridge

IB Footbridge

) ) ) Waterfall

Yosemite

Wilderness

SOURCE: NPS, 1997, 2006, 2010, 2011

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-9

Segment 2 - Overview of Preferred

Alternative Wetland Impacts

0 0.25

Miles

Merced River

Village Drive

Housekeeping

Camp

Northside Drive

M e r c e

d

R i v e r

Sentinel Crossover

Southside Drive

Crossover

Tecoya Road

Ahwahnee Road

Ahwahnee

Meadow

Facilities Impact Area

Recreational WSR Corridor Classification

Surfaced Area

Building

Impacted Wetlands/Waters of the U.S. - 2.56 acres

Wetlands

Palustrine Emergent Wetland - 1.21 acres impacted

Palustrine Forested Wetland - 0.96 acres impacted

Palustrine Scrub Shrub Wetland

Other Waters of the U.S.

Riverine Intermittent - 0.39 acres impacted

Restoration

Meadow Restoration

Riparian Restoration

Stream/River

Valley Loop Trail

Bike path

Trail

SOURCE: NPS, 1997, 2006, 2010, 2011

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-10

Segment 2 - Preferred Alternative Camp 6 and

Yosemite Village Wetland Impacts

0 200

Feet
Camp 4

Yosemite

Lodge

Sentinel

Beach

Leidig

Meadow

Swinging

Bridge

Sentinel Boardwalk

Yosemite Lodge Road

Northside Drive

Valley Loop Trail

Facilities Impact Area

Recreational WSR Corridor Classification

Surfaced Area

Building

Campground

Impacted Wetlands/Waters of the U.S. - 0.05 acres

Wetlands

Palustrine Emergent Wetland - 0.01 impacted

Palustrine Forested Wetland

Palustrine Scrub Shrub Wetland

Other Waters of the U.S.

Riverine Intermittent - 0.03 acres impacted

Riverine Perennial - 0.01 acres impacted

Restoration

Meadow Restoration

Potential Meadow Restoration

Riparian Restoration

Riparian and Floodplain

Stream/River

Valley Loop Trail

Bike path

Trail

SOURCE: NPS, 1997, 2006, 2010, 2011

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-11

Segment 2 - Preferred Alternative

Yosemite Lodge and Camp 4 Wetland Impacts

0 200

Feet
Lower Pines

Campground

Stoneman

Boardwalk

Facilities Impact Area

Recreational WSR Corridor Classification

Surfaced Area

Building

Campground

Impacted Wetlands/Waters of the U.S. - 0.06 acres

Wetlands

Palustrine Emergent Wetland - 0.04 acres impacted

Palustrine Forested Wetland

Palustrine Scrub Shrub Wetland

Other Waters of the U.S.

Riverine Intermittent - .02 acres impacted

Restoration

Meadow Restoration

Riparian Restoration

Stream/River

Valley Loop Trail

Bike path

Boardwalk

SOURCE: NPS, 1997, 2006, 2010, 2011

Map Area

Segment

4

Segment

3

Segment

2 Segment

1

Segment

5

Segments

6,7

Segment

8

Recreational Segment Scenic Segment Wild Segment

Merced River Comprehensive Management Plan and EIS . 210436

Figure O-12

Segment 2 - Preferred Alternative

Curry Village Wetland Impacts

0 200

Feet
APPENDIX O 

O-24 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

Restoration 

Proposed restoration management actions under Alternative 5 would improve hydrologic function 

and restore ecological integrity of the Merced River corridor, including associated plant communities 

and wetlands. Management actions under Alternative 5 would result in the restoration of 

approximately 40.52 acres of wetlands in Segments 2 and 4, which represents a corridorwide, longterm, moderate, beneficial impacts on wetlands. 

The primary components which would benefit wetlands in all segments (Segments 1-8) in the longterm include the following: 

 Removal of Abandoned Infrastructure – Abandoned underground infrastructure would be 

removed that alters hydrology, including remnants of abandoned sewer treatment facilities, 

sewer and water lines, and manholes. This infrastructure currently contributes to dewatering 

of meadows and wetlands, and alteration of the natural hydrologic regime of the Merced 

River. Areas of removed infrastructure would be restored to natural conditions, including 

revegetation with native plants. 

 Restoration of Eroded and Vulnerable Riverbanks – Areas with denuded vegetation and areas 

susceptible to erosion would be stabilized and revegetated with native plants. Re-vegetated 

areas would be protected using closure signs, fencing, and/or other natural barriers such as 

rocks and logs as deterrents. 

 Protection of the Riparian Zone – The riparian zone would be protected from new development 

within 150’ from the ordinary high water mark. Campsites within 100’ feet of the ordinary high 

water mark would be removed or relocated. 

 Removal and Replacement of Riprap –Riprap would be removed where possible to restore 

natural river processes. Riprap would be replaced with native riparian vegetation, using 

bioengineering techniques if riverbank stabilization is still necessary for infrastructure 

protection. 

 Addressing Trails in Sensitive Habitat – Trails would be rerouted out of sensitive habitats or 

boardwalks would be installed through wetlands. New trail routes should avoid wetlands and 

special status habitat. 

In Segment 1, additional actions include requiring administrative pack stock to feed on pellet feed that 

is packed into the site instead of allowing pack stock to graze in meadow areas. This would help 

protect meadow vegetation from high levels of grazing by reducing the level of vegetation trampling by 

administrative pack stock and reducing the dispersal of manure and roll pits. 

In Segment 2, the location of some roads and trails bisect or otherwise cross through meadows and 

cause fragmentation, soil compaction, and vegetation trampling of Valley meadows. Additionally, 

these roads and trails limit or disrupt meadow hydrologic connectivity. To address these issues, fill 

would be removed from wetlands and sensitive areas at the Ahwahnee Meadow, boardwalks would be 

installed in wet areas, and culverts would be added to improve hydrologic connectivity. Stoneman 

Meadow would be restored by removing roadside parking and unnatural fill material, and extending 

fencing to protect wetlands, and the Curry Orchard parking lot would be redesigned to promote water 

flow from the cliff walls to Stoneman Meadow. In addition, fencing would be installed along the 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-25

northern perimeter of El Capitan Meadow and boardwalks, and viewing platforms would be installed 

to reduce habitat fragmentation; boardwalks would be constructed at the Valley Loop Trail as well to 

reduce impacts on wet meadow habitat in Slaughterhouse Meadow. These actions would collectively 

improve meadow and wetland habitat integrity, and enhance contiguity of meadow habitats as well as 

hydrological connectivity between meadow, riparian, and floodplain habitats. 

In Segment 4, the Greenemeyer Sandpit contains fill material that precludes natural flooding and 

regeneration of riparian plant communities. The Greenemeyer Sandpit would be restored to natural 

conditions. Fill material would be removed and the topography recontoured. Native riparian 

vegetation would be planted to restore the natural vegetation for the site. Abbieville and the Trailer 

Village contain impacts of former development, including paved roads and parking and compacted 

soils within 150 feet of the riverbanks. Asphalt and imported fill would be removed. The area would be 

recontoured and planted with native riparian species and oaks. 

Overall, restoration activities have the potential to create localized, short-term, minor, adverse 

impacts. For example, construction activities associated with restoration management actions could 

result in damage to or removal of vegetation, and the potential introduction and spread of invasive 

nonnative species. However, restoration activities are anticipated to result in net long-term, beneficial 

impacts as natural ecological processes are restored. 

FUNCTIONS AND VALUES 

This section describes the functions and values of the wetland types impacted under Alternative 5: 

Palustrine emergent wetlands, palustrine forested wetlands, riverine intermittent wetlands, and 

riverine perennial wetlands. The following functions and values were evaluated based on those 

described in Procedural Manual #77-1: 

 Biotic functions, including fish and wildlife habitat, plant productivity, native species, habitat 

diversity, threatened and endangered species; 

 Hydrologic functions, including flood attenuation, streamflow maintenance, groundwater 

recharge and discharge, water supply, erosion and sediment control, water purification, and 

detrital export to downstream systems; 

 Cultural values, including aesthetics, education, historical values, archaeological values, 

recreation, and interpretation; 

 Research/scientific values, including potential references sites for scientific research; and 

 Economic values, including flood protection, fisheries, and tourism. 
APPENDIX O 

O-26 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

Palustrine Habitats 

Biotic Functions 

The relatively dense layer of herbaceous vegetation in the palustrine emergent wetlands provides a 

variety of benefits for many wildlife species. In particular, the meadow communities provide foraging 

habitat for raptors and perennial range habitat for deer to bed and forage. The palustrine forested 

wetlands provide several benefits for wildlife species; specifically, it provides nesting and perching 

habitat for several species of birds, and leaf litter provides habitat for smaller animals. All the palustrine 

wetlands provide habitat for pollinators and other invertebrates. 

Hydrologic Functions 

Palustrine habitats could play an important role in flood attenuation and sediment retention. In 

addition, wetlands located below roads and other developed areas may serve to retain sediment and 

degrade nutrients before the runoff enters downstream systems. 

Cultural Values 

The palustrine habitats in the study area do not contain any known archaeological sites. Apparent 

cultural values inclue the significant aesthetic values that meadow and riparian wetlands provide, 

particularly in contrast to the steep, rocky walls of the valley. Interpretive guides and the meadow 

clearings that allow majestic views of the park have brought appreciation and awareness of wetlands to 

the millions of park visitors that have visited the area for decades. 

Research/Scientific Values 

Palustrine habitats, particularly emergent wetlands, provide rich opportunities for scientific research. 

Climate change, development, and vegetation management practices have caused changes in plant 

communities in the meadows. Such changes may be reflected in the floodplain sediments through 

charcoal debris and the pollen record, which may be amendable to scientific study. 

Economic Values 

For the reasons listed above, the palustrine habitats could provide significant economic value for flood 

protection, biological resources (in particular fisheries), and tourism. 

Riverine Habitats 

Biotic Functions 

The Merced River provides a year-round water source for wildlife and habitat for fish and aquatic 

invertebrates. The intermittent channels provide a seasonal water source for wildlife and invertebrates. 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-27

Because the unconsolidated shore habitats lack vegetation and usually lack water, they may not 

provide significant habitat or food sources for wildlife. 

Hydrologic Functions 

The hydrologic functions of the Merced River are flood attenuation, streamflow maintenance, water 

supply, erosion control, sediment retention, water purification, and detrital export (including large 

woody debris) to downstream systems. Additionally, because of the coarse texture of the sediments 

that make up the Merced River channel, riverine habitats along the Merced River could offer some 

degree of groundwater recharge function. The intermittent channels are periodic water sources and 

therefore provide less function; however, they nevertheless contribute streamflow maintenance, water 

supply, erosion control, sediment retention, water purification, and detrital export to downstream 

systems. 

Cultural Values 

Because Native Americans are known to have focused some activities along streams, riverine habitats 

may provide archaeological value. Perennial channels also provide an aesthetic value. Visitors to the 

park enjoy the Merced River and engage in activities such as swimming, boating, fishing, and 

photography. The seasonal water flow and seasonal lack of vegetation in the intermittent channels 

limit the aesthetic value of these habitats. 

Research/Scientific Values 

The riverine habitats may provide opportunities for research in groundwater-vegetation relationships 

and in the effectiveness of riparian habitat restoration techniques. 

Economic Values 

For the reasons listed above, the riverine habitats could provide significant economic value for flood 

protection, biological resources (in particular fisheries), and tourism. 

JUSTIFICATION 

Alternatives Considered 

The range of alternatives considered in the Merced River Plan DEIS, presented in the “Alternatives” 

(Chapter 8), include the No Action Alternative (Alternative 1), Self-Reliant Visitor Experiences and 

Extensive Floodplain Restoration (Alternative 2), Dispersed Visitor Experiences and Extensive 

Riverbank Restoration (Alternative 3), Resource-based Visitor Experiences and Targeted Riverbank 

Restoration (Alternative 4), and Diversified Visitor Experiences and Selective Riverbank Restoration 

(Alternative 6). 
APPENDIX O 

O-28 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

Alternative 1 

Alternative 1 provides a baseline on which to compare impacts from Alternatives 2 through 6. However, 

with wetland impact minimization and various restoration measures included in the preferred alternative, 

Alternative 1 may not necessarily be less damaging overall to wetlands because it would forego numerous 

opportunities for restoration. Further, it does not accomplish the purpose of the project. 

Alternative 2 

The guiding principles of Alternative 2 include maximizing the restoration of the 100-year floodplain by 

removing infrastructure not essential to resource-related recreation, and creating a more self-reliant 

visitor experience, where less commercial services are available. Visitor-use levels are managed to allow 

for visitor experiences free of crowding or congestion. Alternative 2 would restore up to approximately 

347 acres of vegetation, including 47.97 acres of wetlands, as a result of actions common to 

Alternatives 2-6 and those specific to Alternative 2. Actions to manage visitor use and facilities would 

result in the loss of approximately 32.37 acres of vegetation and the permanent loss of 2.87 acres of 

potentially jurisdictional wetlands as a result of actions specific to Alternative 2. This alternative 

includes large-scale wetland restoration actions including removal of the road through Stoneman 

Meadow, removal of Northside Drive through Ahwahnee Meadow, removal of parking outside the 

10-year floodplain at the Yosemite Village Day Use Parking Area, the removal of roadside parking 

along Yosemite Valley meadows complete closure and ecological restoration of Housekeeping Camp, 

and the restoration of Wawona Golf Course to meadow habitat. These actions are possible when 

coupled with the decrease in daily Yosemite Valley visitation proposed under Alternative 2. 

Alternative 3 

The guiding principles of Alternative 3 include restoration of large portions of the floodplain and the 

riparian area within 150 feet of the river. This alternative accommodates much lower maximum visitor 

use levels than today, and offers fewer commercial services and facilities. Visitor use levels are managed 

to allow for dispersed visitor experiences free of crowding or congestion. Alternative 3 would restore 

approximately 302 acres of vegetation, including 46.79 acres of wetlands, as a result of actions 

common to Alternatives 2-6 in conjunction with actions specific to Alternative 3. Actions to manage 

visitor use and facilities would result in the loss of approximately 31.66 acres of vegetation and the 

permanent loss of 2.75 acres of potentially jurisdictional wetlands as a result of actions specific to 

Alternative 3. This alternative includes robust wetland restoration actions including removal of the 

road through Stoneman Meadow, removal of Northside Drive through Ahwahnee Meadow, removal 

of parking outside the 10-year floodplain at the Yosemite Village Day Use Parking Area, the removal of 

roadside parking along Yosemite Valley meadows and the restoration of Wawona Golf Course to 

meadow habitat. 

Alternative 4 

The guiding principles of Alternative 4 include restoration of portions of the floodplain and the riparian 

area within 150 feet of the river. This alternative focuses on providing only those commercial services 

and facilities that facilitate resource-based visitor experiences. It accommodates lower maximum visitor 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-29

use levels than today, with large increase in overnight camping capacity and moderate decreases in the 

overnight lodging capacity. Alternative 4 would restore approximately 223 acres of vegetation, 

including 44.57 acres of wetlands, as a result of actions common to Alternatives 2-6 and those specific 

to Alternative 4. Actions to manage visitor use and facilities would result in the loss of approximately 

34.57 acres of vegetation and the permanent loss of 2.67 acres of potentially jurisdictional wetlands as a 

result of actions specific to Alternative 4. This alternative includes targeted wetland restoration actions 

including removal of the road through Stoneman Meadow, removal of parking 150 feet away from the 

river at the Yosemite Village Day Use Parking Area, and the removal of roadside parking along 

Yosemite Valley meadows. 

Alternative 6 

The guiding principles of Alternative 6 include limited restoration within 100 feet of the river and in 

meadow and riparian areas, infrastructure improvements to accommodate growth in peak daily 

visitation in Yosemite Valley, and expansion of facilities and services to allow for diversified visitor 

experiences. Alternative 6 would restore approximately 170 acres of vegetation, including 37.37 acres 

of wetlands, as a result of actions common to Alternatives 2-6 and those specific to Alternative 6. 

Actions to manage visitor use and facilities would result in the loss of approximately 36.89 acres of 

vegetation and the permanent loss of 2.67 acres of potentially jurisdictional wetlands as a result of 

actions specific to Alternative 6. This alternative includes focused wetland restoration actions 

including removal of parking 150 feet away from the river at the Yosemite Village Day-use Parking 

Area and the removal of roadside parking along Yosemite Valley meadows. 

Nonwetland Alternatives to the Proposed Action 

The Merced River Plan/DEIS involves comprehensive management within the Merced River corridor, 

which includes riverine, palustrine and lacustrine habitat. The purpose of the Merced River Plan is to 

provide a comprehensive management plan for the protection of the Merced River’s free-flowing 

condition, water quality, and the values that make the river worthy of designation. There are no 

alternatives to the proposed action that could be located outside the floodplain or wetland and aquatic 

habitat of the Merced River corridor, as the plan is focused upon enhancements to aquatic habitats. 

Design or Modifications to Minimize Harm to Wetlands 

Mitigation Measures 

A full list of mitigation measures prescribed for the Merced River Plan/DEIS are outlined in 

Appendix C. Mitigation measures specific to wetland resources are summarized below. The National 

Park Service (and its contractors) shall implement the following mitigation measures, as appropriate, 

prior to, during, and/or after construction activities. Specific tasks would include, but are not limited 

to, the following: 
APPENDIX O 

O-30 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

Hydrology and Water Quality 

 MM-HYD-1. Contractor shall prepare and implement a Stormwater Pollution Prevention 

Plan (SWPPP) that designates construction best management practices to be used to control 

the sources of fine sediment and to capture and filter it before entering the river. The SWPPP 

shall define the characteristics of the site, identify the type of construction that will be 

occurring, and describe the practices that will be implemented to control erosion and the 

release of pollutants in stormwater. At a minimum, the SWPPP shall address the following, as 

applicable:

Stabilization Practices 

– The stabilization practices to be implemented shall specify the intended stabilization 

practices, which may include one or more of the following: temporary seeding, mulching, 

geotextiles, sod stabilization, vegetative buffer strips, erosion control mats, protection of 

trees, preservation of mature vegetation, etc. On the daily CQC Report, the Contractor 

shall record the dates when the major grading activities occur, (e.g., clearing and grubbing, 

excavation, embankment, and/or grading); when construction activities temporarily or 

permanently cease on a portion of the site; and when stabilization practices are initiated. 

Unless otherwise directed by the Contracting Officer for the reasons below (i.e., 

unsuitable conditions or no activity for less than 21 days), stabilization practices shall be 

initiated as soon as practicable, in any portion of the site where construction activities 

have temporarily or permanently ceased, but no more than 14 calendar days after the 

activities cease. 

– Unsuitable Conditions - Where the initiation of stabilization measures by the 14th day 

after construction activity temporarily or permanently ceases is precluded by unsuitable 

conditions caused by the weather, stabilization practices shall be initiated as soon as 

practicable after conditions become suitable. 

– No Activity for Less Than 21 Days - Where construction activity will resume on a portion 

of the site within 21 days from when activities ceased (e.g., the total time period that 

construction activity is temporarily ceased is less than 21 days), then stabilization practices 

do not have to be initiated on that portion of the site by the 14th day after construction 

activity temporarily ceased. 

Structural Practices 

– The Contractor shall implement structural practices to divert flows from exposed soils, 

temporarily store flows, or otherwise limit runoff and the discharge of pollutants from 

exposed areas of the site. Structural practices shall be implemented in a timely manner 

during the construction process to minimize erosion and sediment runoff. Location and 

details of installation of structural practices shall be depicted on the construction 

drawings. 

Silt Fences 

– The Contractor shall provide silt fences as a temporary structural practice to minimize 

erosion and sediment runoff. Silt fences shall be properly installed to effectively retain 

sediment immediately after completing each phase of work where erosion would occur in 

the form of sheet and rill erosion (e.g. clearing and grubbing, excavation, embankment, 

and grading). Silt fences shall be installed in the locations indicated on the drawings or as 

needed based on Contractor operations. Final removal of silt fence barriers shall be upon 

approval by the Contracting Officer. 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-31

– Silt fences shall extend a minimum of 16 inches above the ground surface and shall not 

exceed 34 inches above the ground surface. Filter fabric shall be from a continuous roll cut 

to the length of the barrier to avoid the use of joints. When joints are unavoidable, filter 

fabric shall be spliced together at a support post, with a minimum 6-inch overlap, and 

securely sealed. A trench shall be excavated approximately 4 inches wide and 4 inches 

deep on the upslope side of the location of the silt fence. The 4-inch by 4-inch trench shall 

be backfilled and the soil compacted over the filter fabric. Silt fences shall be removed 

upon approval by the COR.

Straw Bales 

– Straw bales are not authorized for use in storm water control in Yosemite National Park as 

they have the potential to introduce exotic species into the Park environment. 

Diversion Dikes 

– Diversion dikes shall have a maximum channel slope of 2 percent and shall be adequately 

compacted to prevent failure. The minimum height measured from the top of the dike to 

the bottom of the channel shall be 18 inches. The minimum base width shall be 6 feet and 

the minimum top width shall be 2 feet. The Contractor shall ensure that the diversion 

dikes are not damaged by construction operations or traffic. Diversion dikes shall be 

located as shown on the drawings or as needed based on Contractor operations. Location 

of diversion dikes shall be fully coordinated with cultural and natural environmental 

protection requirements described in Section 01355, Natural, Cultural, and Physical 

Resources Protection. 

Filter Fabric 

– The geotextile shall comply with the requirements of ASTM D 4439, and shall consist of 

polymeric filaments that are formed into a stable network such that filaments retain their 

relative positions. The filament shall consist of a long-chain synthetic polymer composed 

of at least 85 percent by weight of ester, propylene, or amide, and shall contain stabilizers 

and/or inhibitors added to the base plastic to make the filaments resistance to 

deterioration due to ultraviolet and heat exposure. Synthetic filter fabric shall contain 

ultraviolet ray inhibitors and stabilizers to provide a minimum of six months of expected 

usable construction life at a temperature range of 0 to 120 degrees F. The filter fabric shall 

meet the following requirements: 

FILTER FABRIC FOR SILT SCREEN FENCE 

Physical Property Test Procedure Strength Requirement

Grab Tensile ASTM D 4632 100 lbs. min. 

Elongation (%) 30 % max. 

Trapezoid Tear ASTM D 4533 55 lbs. min. 

Permittivity ASTM D 4491 0.2 sec-1

AOS (U.S. Std Sieve) ASTM D 4751 20-100 

Silt Fence Stakes and Posts 

– The Contractor may use either wooden stakes or steel posts for fence construction. 

Wooden stakes utilized for silt fence construction, shall have a minimum cross section of 2 

inches by 2 inches when hardwood is used and 4 inches by 4 inches when softwood is 

used, and shall have a minimum length of 5 feet. Steel posts (standard "U" or "T" section) 
APPENDIX O 

O-32 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

utilized for silt fence construction, shall have a minimum weight of 1.33 pounds per linear 

foot and a minimum length of 5 feet. 

Identification Storage and Handling 

– Filter fabric shall be identified, stored and handled in accordance with ASTM D 4873.

Maintenance 

– The Contractor shall maintain the temporary and permanent vegetation, erosion and 

sediment control measures, and other protective measures in good and effective operating 

condition by performing routine inspections to determine condition and effectiveness, by 

restoration of destroyed vegetative cover, and by repair of erosion and sediment control 

measures and other protective measures. The following procedures shall be followed to 

maintain the protective measures. 

– Silt fences shall be inspected in accordance with the below paragraph, Inspections. Any 

required repairs shall be made promptly. Close attention shall be paid to the repair of 

damaged silt fence resulting from end runs and undercutting. Should the fabric on a silt 

fence decompose or become ineffective, and the barrier is still necessary, the fabric shall 

be replaced promptly. Sediment deposits shall be removed when deposits reach one-third 

of the height of the barrier. When a silt fence is no longer required, it shall be removed 

with approval of COR. The immediate area occupied by the fence and any sediment 

deposits shall be shaped to an acceptable grade. 

– Diversion dikes shall be inspected in accordance with the below paragraph, Inspections. 

Close attention shall be paid to the repair of damaged diversion dikes and necessary 

repairs shall be accomplished promptly. When diversion dikes are no longer required, 

they shall be shaped to an acceptable grade. 

Inspections 

– The Contractor shall inspect disturbed areas of the construction site, areas used for 

storage of materials that are exposed to precipitation that have not been finally stabilized, 

stabilization practices, structural practices, other controls, and area where vehicles exit the 

site at least once every 7 calendar days and within 24 hours of the end of any storm that 

produces 0.5 inches or more rainfall at the site. Where sites have been finally stabilized, 

such inspection shall be conducted at least once every month. 

– Disturbed areas and areas used for material storage that are exposed to precipitation shall 

be inspected for evidence of, or the potential for, pollutants entering the drainage system. 

Erosion and sediment control measures identified in the Storm Water Pollution 

Prevention Plan shall be observed to ensure that they are operating correctly. Discharge 

locations or points shall be inspected to ascertain whether erosion control measures are 

effective in preventing significant impacts to receiving waters. Locations where vehicles 

exit the site shall be inspected for evidence of offsite sediment tracking. 

– For each inspection conducted, the Contractor shall prepare a report summarizing the 

scope of the inspection, name(s) and qualifications of personnel making the inspection, 

the date(s) of the inspection, major observations relating to the implementation of the 

Storm Water Pollution Prevention Plan, maintenance performed, and actions taken. The 

report shall be furnished to the COR within 24 hours of the inspection as a part of the 

Contractor's daily CQC Report. A copy of the inspection report shall be maintained on the 

job site.
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-33

Wetlands 

 MM-VEG-4. Delineate wetlands and apply protection measures during construction. Wetlands shall 

be delineated by qualified National Park Service staff or certified wetland specialists and clearly marked 

prior to work. Perform activities in a cautious manner to prevent damage caused by equipment, erosion, 

siltation, etc.

 MM-VEG-5. The Contractor shall adhere at all times to the conditions of U.S. Army Corps of 

Engineers Nationwide Permit No. 33, Temporary Construction, Access and Dewatering, with 

the following conditions as a minimum: 

– All work will be subject to the Standard and Technical Conditions of the Certification of 

the California Regional Water Quality Control Board, a copy which will be provided to the 

Contractor. 

– Work in streambeds is to be performed in periods of low water conditions. Contractor 

shall monitor stream flow conditions and weather forecasts at all times during the course 

of the work. During thunderstorms or other intense rain conditions, streambeds at 

Yosemite can fill rapidly. 

– Re-grade and restore disturbed areas to preexisting contours to maintain drainage 

patterns. 

 MM-VEG-6. The Contractor shall fence construction areas adjacent to aquatic habitats to 

prohibit the movement of aquatic species into the construction area and to control siltation 

and disturbance in aquatic habitats. 

– The Contractor shall salvage and reuse wetland soils as fill to the maximum extent 

possible. 

– The Contractor shall use trench plugs where designated on the drawings in wetland areas 

to prevent changes to natural flow patterns. 

– During dewatering, intakes shall be completely screened with wire mesh not larger than 

5 millimeters to prevent aquatic species from entering the pump system. Water shall be 

released or pumped downstream at an appropriate rate to maintain downstream flows 

during construction. 

– Access routes to and through work locations in the meadows and wetlands shall be 

planked with 1 1/8” plywood, stabilization mats or other method approved by the 

contracting officer. 

Refer to Appendix C of the Merced River Plan/ DEIS for a complete list of resource-specific mitigation 

measures applicable to the preferred alternative. The Preferred Alternative has been designed to 

mitigate harmful effects to wetlands. The Merced River Plan/DEIS includes programmatic actions that 

will require preparation of a subsequent statement of findings for specific projects. 

Site Restoration 

Restoration of riverine habitat functions and values is an integral part of the preferred alternative in 

Segments 1-8 of the Merced River corridor. Restoration of 40.52 acres of wetland habitat would improve 

palustrine habitat functions and values in Segments 2 and 4. Additional restoration activities that are 
APPENDIX O 

O-34 Merced Wild and Scenic River Comprehensive Management Plan / DEIS

incorporated into the preferred alternative are described above, under the subheading Environmental 

Consequences of the Proposed Action on Wetlands. 

Proposed Compensation 

The emphasis of the Merced River Plan is to avoid and minimize impacts to wetland resources. 

Approximately 2.67 acres of wetlands would be impacted by Alternative 5, including 1.26 acres of 

palustrine emergent wetlands, 0.96 acres of palustrine forested wetlands, 0.44 of riverine intermittent 

wetlands, and 0.01 acres of riverine perennial wetlands. Compensation will be required for the direct 

impact to 2.67 acres of wetlands at Curry Village, Camp 6 and Yosemite Village, and Yosemite Lodge 

and Camp 4. The wetland features that would be affected by the proposed activities provide important 

natural functions such as nutrient cycling, sediment entrapment, and habitat for wildlife. Because this 

project must ensure “no net loss” of wetland functions or values, compensation of a minimum of 

2.67 acres of wetland would be required. 

The NPS will provide compensation through the restoration of approximately 40.37 acres of wetlands 

in Segment 2 (see Figures 9-29 through 9-32 in Chapter 9). Figures O-9 through O-12 display the 

locations of proposed actions to restore and enhance wetland habitats in areas near where wetland 

impacts will occur. These restoration actions will provide compensation for the wetland losses 

described above, resulting in a 15:1 habitat compensation ratio. Restored wetland types include 

palustrine forested wetland and palustrine emergent wetland. Restored areas will provide equivalent, if 

not higher, wetland functions and values to those features impacted by the project. In general, in-kind 

mitigation is preferable to out-of-kind mitigation because it is most likely to compensate for the 

functions and values lost at the impact site. However, in the case of the impacted riverine wetlands 

(where the impacts are much less than those to the palustrine wetlands), this habitat type is already 

abundant in the region and a priority was placed on creating additional palustrine emergent and 

forested wetlands, as this habitat type would adequately compensate for the lost functions and values 

of the riverine wetlands. 

CONCLUSION 

The proposed action would have a beneficial impact on the extent, function, and value of wetlands by 

implementing restoration management actions for the Merced River corridor. These management 

actions would include the removal of abandoned infrastructure, restoration of eroded and vulnerable 

riverbanks, protection of the riparian zone within 150’ of the ordinary high water mark, removal of 

campsites within 100’ of the ordinary high water mark, removal and replacement of riprap, and the 

rerouting of trails from sensitive habitat, including wetlands. The removal of fill from wetland and 

riparian areas would result in the net creation of wetlands within Segments 2 and 4. The net result of 

these actions would be improved hydrologic function and the restoration of ecological integrity of the 

Merced River, including associated plant communities and wetlands. 

Approximately 2.67 acres of wetlands will be impacted by implementation of Alternative 5, including 

1.26 acres of palustrine emergent wetlands, 0.96 acres of palustrine forested wetlands, 0.44 of riverine 
Wetland Statement of Findings for the 

Draft Merced Wild and Scenic River Comprehensive Management Plan 

Merced Wild and Scenic River Comprehensive Management Plan / DEIS O-35

intermittent wetlands, and 0.01 acres of riverine perennial wetlands. The NPS will provide 

compensation through the restoration of approximately 40.37 acres of wetlands in Segment 2 

The National Park Service has determined that there is no practicable alternative that could be located 

outside the floodplain or wetland habitat. Mitigation and compliance with regulations and policies to 

prevent impacts to water quality, wetland function and values, and loss of property or human life 

would be strictly adhered to during and after construction. 

Subsequent project-level documentation may be required for future development projects. Individual 

permits with other federal and cooperating state and local agencies will be obtained or updated as 

appropriate prior to any development activities. Therefore, the National Park Service finds the 

proposed action to be acceptable under Executive Order 11990 for the protection of wetlands. 

Recommended: 

Superintendent, Yosemite National Park Date 

Certification of Technical Adequacy and Servicewide Consistency: 

Chief Water Resources Division Date 

or Professional Wetland Scientist, National Park Service 

Approved: 

Regional Director Pacific West Region, National Park Service Date