C

Professor, Department of Civil Engineering and

Engineering Mechanics, the University of Arizona.

2. Applicability

This pamphlet applies to all USACE commands with

responsibility for hydraulic and structural design,

construction, and operation of inland navigation

projects .

3. General

The monograph was originally prepared for use by

the Chinese as a goodwill gesture, and not as a

contract . The author used her knowledge and input

from various sources within USACE . She expressed

an interest in sharing her work at no cost to USACE .

4 . Distribution Statement

Approved for public release ; distribution is

unlimited.

FOR THE COMMANDER:

worked as a hydraulic engineer with USACE for

30 years ending as Chief, Planning Branch, Sacramento District, before becoming an associate professor . Her work with the USACE encompassed

some of the nation's largest water resource development projects including the Mississippi River floodcontrol and navigation effort, Missouri River

reservoirs and navigation improvements, Arkansas

River navigation improvements, California's Sacramento-San Joaquin Delta project, and the $1 billion

Marysville Lake reservoir and Yuba River in California . After leaving USACE, Petersen developed new

graduate-level courses, wrote two textbooks, and

lectured in China, Morocco, and South Africa .

OTIS WILLIAMS

Colonel, Corps of Engineers

Chief of Staff
$

m

O.v

INLAND NAVIGATION AND CANALIZATION

Margaret S . Petersen, Emerita Associate Professor

Department of Civil Engineering and Engineering Mechanics

The University of Arizona, Tucson, Arizona, U .S .A.

TABLE OF CONTENTS

1 .UUK w aus

i

P

1 . INTRODUCTION 1

2. PLANNING FOR CANALIZATION 2

3 . NAVIGATION LOCKS AND DAMS 3

4. PHYSICAL FACTORS AJiFECTING SITING OF NAVIGATION

STRUCTURES 4

4.1 Terrain

4.2 Geology and Soils . 4

4.3 Streamflow and River Stage . 4

4.4 Ground Water 4

4.5 Climate 4

4.6 Sediment 4

4.7 Environmental Resources 4

4.8 Infrastructure and Commercial Resources 4

5 . INLAND NAVIGATION CRITERIA 5

5.1 Minimum Dependable Depth . 5

5 .2 Adequate Channel Width 5

5.3 Freedom from Hazardous Currents 5

5.4 -

Minimizing Lock Transit Time 5

5.5 Terminal Facilities 5

6. OTHER DESIGN REQUIREMENTS 6

6.1 Flood Stages . 6

6.2 Drainage 6

6.3 Water Supply Intakes 6

6.4 Sewage Contamination 6

6.5 Vector Control 6

6.6 Fish and Wildlife 6

6.7 Recreation 6

6.8 Hydropower 6
Availability of Construction Materials

8.2

- Lock Design Criteria .

Lock Size and Number of Locks

-

Lock Lift

8.3- Lock Types .

8.4- Lock Depth and Lock Floor .

8.5 - Lock Gates and Sills .

Miter Gates .

Tainter Gates .

Sector Gates .

Lift Gates

Emergency Closure Sills

8.6- Lock Walls .

Lock Chamber Walls

Upper and Lower Gate-Bay Walls

Culvert-Intake Walls .

Culvert-Discharge Walls

Approach (Guard and Guide) Walls

8 .7

Lock Filling and Emptying Systems

Hawser Stresses

Filling and Emptying Over, Between, or Around Lock Gates

Filling and Emptying by Valves in Gates or through Short

Culverts

Filling and Emptying through Wall Culverts and Ports or

Laterals

Early conventional wall culvert and port systems

Modern systems.

Intake manifolds

Control valves .

Wall culverts . .

Wall-port systems

TVA multiport system

11

• 

• 8

-3

• 8-3

8-3

8-4

• 8

-4

8-5

• 8.6

8-8

8 • -8

8-8

8-8

• 8-8

8-9

8-10

8-10

8-10

•

.8-11

• 8-11

• 8-12

.8-13

8-14

• 8

-14

• 8-15

8-15

• 8-15

• 8

-16

8-18

• 8-19

8-19

• 8-20
C

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Lock chamber lateral diffusers

Lock emptying systems

Bottom Longitudinal Filling and Emptying Systems

Culvert area ratios .

Longitudinal floor distribution culverts

Port manifolds

Ports ..

Operation ,

8.8 - Emergency Closure Facilities for Locks ,

10.1 Arkansas River Dredging

10.2 Mississippi River Dredging .

10.3 Missouri River Dredging .

10.4 Red River Dredging .

10.5 Effect of Hinged Pool Operation on Maintenance Dredging

10.6 Dredging Equipment . .

Mechanical Dredges .

Hydraulic Suction Dredges

-Hopper dredges

Sidecasting dredges

Hydraulic pipeline dredges

10.7 -Dredged Material Disposal .

in

9. NAVIGATION CONDITIONS IN LOCK APPROACHES

9

9.1 Dardanelle Lock and Dam, Arkansas River . 9

9.2 Lock and Dam 2, Red River . 9

9.3 Robert S . Kerr Lock and Dam, Arkansas River . 9

9.4 Olmsted Lock and Dam, Ohio River . 9

9.5Canal Surge and Tow Squat . . 9

Temporary Lock 52, Ohio River . 9

Bay Springs Lock and Dam . 9

Lock and Dam 17, Verdigris River (Choteau Lock and Dam,

Arkansas River Navigation Project) .. 9

Shoaling . 9

10. DREDGING

1

8

8

• 8

• 8

• 8

8

8

8

• 8

1

•

1

1

1

1

1

1

•

1

1

1

1

1

11 .INNOVATIVE LOCK DESIGN 1

11 .1 - Need for Rehabilitation or Replacement of Navigation Structures . . 1

11 .2 - Increasing Lock Capacity . 1

11 .3 - Need for Innovation in Lock Design . 1

11 .4Innovative Lock Design Program . 1

Winfield Locks and Dam, Kanawha River . . 1

Modeling Program . . 1
Marmet Lock and Darn, Kanawha River 11

APPENDIX A REFERENCES A-

APPENDIX BRED RIVER WATERWAY B

B.1 Project Description .

B.2 Sediment

B.3 Hinged Pool Operation

B.4 Reaeration .

B.5 Optimization of Spillway Design

Attachment B.1 - Typical Spillway. Optimization Study, Red River, Louisiana,

Appendix D, CE EM 1110-2-1605, 12 May 1987) .

B-

B-

B-

•

B-

B-

•

B-

INDEX•. I-1

iv
CONVERSION FACTORS, NON-SI TO SI UNITS OF MEASUREMENT

Non-SI units of measurement used in this report can be converted to SI (metric) unit

follows:

v

Multiply by To obtain

inch 2.54 centimeters

foot 0.3048 meters

mile 1 .609 kilometers

square feet 0.0929 square meters

acre 4,047 square meters

acre 0.405 hectare

square mile 259 hectare

square mile 2590 square kilometer

cubic feet 0.0283 cubic meters

cubic yards 0.765 cubic meters

acre-feet 1,233 cubic meters

cubic feet per second 0.0283 cubic meters per

second

feet per second 0.305 meters per second

pounds (mass)

pounds per cubic foot

0.454

16.0185

kilograms

kilograms per cubic

meter

pounds (force)

pounds per square

inch

0.454

6,895

kilograms

pascals

gravitational

acceleration (ft/sec)

9.807 meters/sect
FOREWORD

This monograph describes the design of inland waterways in the United States by the U .

Army, Corps of Engineers (USACE). The Corps of Engineers maintains an 11,000-mile shallow

draft inland waterways system with 211 locks at 168 sites and more than 180 navigation dam

with normal heads ranging from one ft to over 100 ft .

Sections 7 and 8 summarize criteria generally used for design of canalization project

constructed in the United States in the period 1950 through 1993 . Material presented draw

extensively on guidelines of the U.S. Army, Corps of Engineers; Miscellaneous Papers by T. 

Murphy and J. P. Davis issued by the USACE Waterways Experiment Station, Vicksburg

Mississippi ; and on the book River Engineering, M . S. Petersen, Prentice Hall, 1986 . Many 

the existing navigation structures have been in use for more than 50 to 60 years and now are o

insufficient size or have deteriorated to the point where they cannot meet the needs of th

shipping industry and, accordingly, are in need of rehabilitation or replacement .

The Water Resources Development Act of 1986, which authorized replacement of eig

locks, also introduced requirements for cost-sharing for new locks and for major rehabilitatio

of existing locks. The cost of construction is now divided equally between the federa

government and the Inland Waterway Trust Fund (IWTF) . Funds accrue to the IWTF from tax

on fuel used on the inland waterways system, currently 20 cents per gallon .

In recent, years the cost of replacement structures has increased significantly, and th

Corps of Engineers is exploring innovative modifications of traditional lock designs to low

construction and operation .and maintenance costs while meeting the needs of today's navigatio

industry . Currently available information on these innovative measures is presented in Secti

11.

Appreciation is expressed to Samuel B . Powell, Office of the Chief of Engineers ; Tas

Schmidgall, Hydraulics Section, Southwestern Division, Corps of Engineers ; Gary Dyhouse, S

Louis District, Corps of Engineers; and John George, Hydraulic Structures Division, USACE

Waterways Experiment Station, for their kind contributions to this work .

vi
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INLAND NAVIGATION AND CANALIZATION

Margaret S. Petersen, Emerita Associate Professor

Department of Civil Engineering and Engineering Mechanics

The University of Arizona, Tucson, Arizona, U.S .A.

1INTRODUCTION

This monograph describes the design of shallow-draft inland waterways in the Uni

States (U. S .) by the U .S . Army, Corps of Engineers (USACE) . The Corps maintains an 11,0

mile inland waterways system, Figure 1 .1, with 211 locks at 168 sites and more than 

navigation dams with normal heads from one ft to over 100 ft. This system handled more t

530 million tons of commerce in 1992, and total ton-miles that year was a record 271 billi

(Antle and Grier, 1995).

Commodities moving on the system vary geographically and include coal, gra

petroleum, chemicals, and aggregates, all relatively low-value bulk materials . In the order of 

percent of U.S . grain exports and 20 percent of coal exports move on the system . About 

percent of electricity generated in the U.S. is coal-fired, and about 25 percent of this coal 

transported by water (Antle and Grier, 1995) .

Most inland navigation facilities in the U .S. are about 50 years old, and systems on s

rivers, modernized in the past, are in need of rehabilitation or replacement at this ti

Navigation locks and dams on the Upper Mississippi and Illinois Rivers were constructed in 

1930s, those on the Tennessee River in the 1950s and 60s, and those on the Ohio, Arkansas, a

Columbia/Snake Rivers in the 1960s and 70s. The most recently completed systems are 

Tennessee-Tombigbee Waterway opened in 1985 and the Red River Navigation Projec

Louisiana, opened in December 1994 . Modernization and replacement of older locks 

continuing.

National objectives in developing rivers for safe and efficient inland navigation inclu

a. Promoting the production and distribution of food resources .

b. Promoting the expansion of existing and development of new industrial producti

c. Enhancing economic development in general .

d. Enhancing social well-being .

e. Achieving these objectives while preserving and enhancing fish and wildlife resourc

and environmental quality .

Development of inland waterways for commercial navigation can be achieved in th

general ways:

1-1
a. "Open river" development of rivers that have adequate flows to provide navigable

depths in the navigation season .

b. "Canalized" development, of rivers that do not have sufficient depths for navigation

by a series of locks and dams to impound pools of adequate depth .

c. Canal development by excavating channels across land areas .

The type of development to be used on a specific river depends on local conditions and on costs

if more than one type of development would be equally suitable . The primary consideration i

whether or not flows will be adequate to provide sufficient depth in the "navigation season ."

Local climate may limit the navigation season to periods of adequate rainfall or to warmer

months in cold climates where ice blocks the river in winter . Also, high river stages and hig

velocities during floods interrupt navigation . The Upper Mississippi River freezes over every

winter, and the river is closed to navigation from about early December to mid-March due to ice 

The Upper Mississippi is also closed to navigation at other times of year during floods when the

dams "go out of operation," (all spillway gates fully open) and pool levels are within 2 ft of th

top of lock walls . At Lock and Dam 22, for example, this is a flow of 160,000 . Navigatio

ceases on both the Arkansas River and the Red River at the 10 percent recurrence frequency

when velocities and currents become too high for safe and efficient tow operation .

Few rivers, except in tidal reaches, have adequate dimensions and suitable velocities for

open river navigation . Where streamflow does not naturally provide adequate depths for openriver development throughout the year, upstream reservoir storage may be used to provide

controlled releases and adequate depths in downstream reaches . Depths can be increased also

by stabilization and rectification work and by maintenance dredging, and levees may be used t

confine flows to a designated floodway .

Canalization (systems of locks) is used to provide adequate depth for navigation in stream

having little discharge and, therefore, depths too shallow for navigation ; in a waterway havin

a steep slope and velocities too high for navigation ; at a waterfall or rapids in a stream that

otherwise provides adequate depth in other reaches .

Canals cut through land generally are used to connect two bodies of water and to bypass

rock outcrops and rapids in rivers. Canals are expensive, requiring acquisition of large tracts of

land for the canal and for disposal of excavated material, and canal banks often require protection

from wave damage because of the restricted channel width .

Development of safe and efficient inland navigation is based on providing the following 

a. Channels of adequate dimensions (depth and width) for navigation .

b. Safe streamflow velocities that are not a hazard to navigation traffic .

c. Harbors and related appurtenances for receipt and shipment of commodities .

d. Compatibility of navigation requirments with other developments, including floo

protection works, transportation networks (roads, railroads), and utility crossings.

1-2
Navigation projects typically include such basic components as :

a. Spillway (gated, uncontrolled, or wickets) .

b. Overflow weir or embankment.

c. Non-overflow embankment.

d. Locks.

e. Navigable pass.

f. Outlet works.

g. Water quality enhancement facilities.

h. Fish passage facilities .

i . Aids to navigation .

Additionally, facilities for generation of hydroelectric power, releases for irrigation or str

maintenance, and recreation may be included, depending on local conditions .

Planning, design criteria, and operating procedures for navigation projects should consi

measures to avoid or minimize adverse ecological impacts, mitigate adverse effects, and prov

environmental enhancement. Particular concerns in the United States (U.S.) are to improve 

dissolved oxygen levels downstream of dams by flow aeration and to prevent nitro

supersaturation on high spillways.
Figure 1 .1 . Shallow-draft Inland Waterways System, United States .

1-4
a

2PLANNING FOR CANALIZATION

The basic objective in developing a design for a canalized waterway is to provide facilities

to meet projected future shipping needs in the most economical way consistent with protection

and enhancement of social and environmental resources throughout the useful life of a project,

(project life) . Project life for navigation work in the United States is usually taken as 50 years

Investigations to determine if a project can handle projected future transportation

equipment and tonnage efficiently and safely include :

a. Economic studies relating to the amount and type of traffic that would use the new

waterway, including :

- Projections of commodities that would move on the new waterway. What

commodities would move? In what amount (annual tonnage)? From what origin, and to what

destination? In what sason would they move? Is there return traffic?

- Estimates of transportation benefits (savings) and intangible effects related to use

of the waterway.

- Estimates of effects of the project on economic development of the region .

b. Evaluation of existing streams, including :

Flood magnitude and frequency .

Channel widths and depths at different seasons of year.

Channel radii in bends at different seasons of year .

Water quality .

Sediment load.

Bank erosion .

Existing transportation facilities .

Existing and planned river crossings (highways, railroads, pipelines, power lines) .

Existing and planned industrial development .

Existing and planned port facilities .

Important habitat areas and other environmental resources .

c. Evaluation of navigation equipment.

Type, size, and draft of navigation equipment (towboats, barges, vessels) currently

using the waterway or connecting channels .

Projected types and size of equipment likely to use the waterway in the future .

d. Physical constraints on a canalization project.

- Are there any geographic or geological features along the river that are likely to

make canalization clearly infeasible?

2-1
- Is streamflow augmentation needed? Is it feasible? (Are there upstream reservoi

sites that can be developed for storage and low-flow augmentation?)

- Is there need for rectification and stabilization of the river to develop adequat

navigable depths and widths?

e. What is optimum lock size for projected traffic and navigation equipment? Numbe

of lock transits required annually throughout the project life to meet needs of shippers?

f. Is a single lock, or multiple locks, most economically efficient for handling projected

traffic at each lock site?

The views of towboat captains who will use the waterway and the U .S . Coast Guard ar

requested with regard to channel dimensions and lock layout . The U.S . Coast Guard i

responsible for navigation safety and navigation aids, such as channel lights and marking buoys

on inland waterways in the United States .

Size of tows using the inland waterways in the U . S . varies widely . Representative to

sizes for some waterways are summarized as follows:

a. Mississippi River .

- Upper Mississippi River (canalized) . Standard tow size is 15 barges, in 

configuration three barges wide and five barges long, Figures 2 .1 and 2 .2 . Towboats have 320

to 6000 horsepower.

- Middle Mississippi River (open-river) . For downbound traffic, standard tow siz

is 25 barges, in a configuration five barges wide and five barges long . For upbound traffic

standard tow size is 30 barges, in a configuration five barges wide and six barges long 

Towboats have 5600 to 6000 horsepower .

- Lower Mississippi River (open-river) . For downbound traffic, standard tow siz

is 30 to 35 loaded barges . For upbound traffic, tow size ranges from 30 to 45 barges dependin

on river conditions and the mix of loaded and empty barges in the tow, Figure 2 .3 . Towboat

have from 5600 to 10,500 horsepower .

b. Arkansas River (canalized) . Standard tow size is eight barges, in a configuration thre

barges and three barges long, with the towboat occupying the middle slot in the last row o

barges. Maximum tow size is 17 barges in a three barge wide by six barge configuration, wit

the towboat occupying the middle slot in the last row . Overall tow length is limited to 1200 

because of the tight (small) radii of some bends .

c. Missouri River (open-river) . Above Kansas City, standard tow size is three or fou

barges, in a configuration two barges wide and two long, and maximum tow size is six barge

in a configuration two barges wide and three long . Below Kansas City, standard tow size is s

to nine loaded barges and 12 empty barges .

2-2
2-3

Figure 2.1 . Twelve-ba

tow reassembled after

double lockage,

Lock and Dam 15,

Upper Mississippi Riv

(Rock Island Argus)

Figure 2.2. Forty-eight-barge 

Lower Mississippi River

(U.S. Army, Corps of Engineer

Vicksburg District)-

Figure 2.3. Fifteen-barge tow

approaching Lock and Dam 22,

Upper Mississippi River

(U.S . Army, Corps of Engineers,

Rock Island District,)
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3NAVIGATION LOCKS AND DAMS

A canalized river is a river that has been transformed from a free-flowing stream t

series of "slackwater" pools with low flow velocities by a series of locks and dams along 

stream. Navigation dams impound the pools, and the locks make it possible for vessels to p

through the dams, either upstream or downstream, from one pool level to the next, Figure 

"Low-head" dams are dams with heads of 10 to 40 ft, and "high-head" dams have heads in exc

of 40 ft. Lock with lifts of less than 30 ft are classified as low-lift locks ; with lifts of 30 t

ft as medium-lift ; and with lifts of more than 50 ft as high-lift locks.

Principal criteria for selection of sites for navigation locks and dams in a particular re

are related to physical characteristics of the reach (foundation conditions, current directions 

magnitude, sediment transport) ; local drainage conditions ; stability of the channel bed at the s

urban, industrial, and agricultural development ; transportation infrastructure ; and environmen

resources, as follows:

a. Reach conditions .

- A history of relatively permanent banks in the reach because recently formed ban

are usually low and costly to protect .

- A channel alignment that provides fairly straight approaches to the lock, with

a sharp bend upstream or a crossing downstream near the lock, to minimize cross currents in 

lock approaches .

- Sufficient width of main channel to accomodate the required spillway length 

the lock, but not excessively wide and costly, or so narrow as to require extensive b

excavation. As lock sites are frequently on the deep concave side of the channel with the l

set out from the bank to provide adequate approach alignment, space left in the main channel f

the spillway may be materially reduced .

- A high narrow overbank that eliminates the need for embankments to impound 

normal pool and reduces embankment heights required for roads to provide land access to t

lock. A narrow overbank also tends to concentrate flood flows in the main channel, tending 

maintain a deeper channel downstream of the dam in the head of the next pool where adequa

navigation depth is critical .

b. Drainage. Insofar as conditions permit, navigation locks and dams should be sited 

that principal tributaries and drains enter the channel near the head of a navigation pool, rat

than in the lower part of the pool, to avoid interference with drainage .

c. Channel bed. The elevation of the future stable bed of the stream must be estimate

taking into account the effects of any cutoffs, any reduction in sediment load due to upstr

storage reservoirs, the effects of any channel contraction works, and the backwater effects of 

navigation dams.

Most locks on inland waterways in the United States are 110 ft wide by 600 or 1200 

long, with gates at both ends (at the upper pool and at the lower pool) . There are water passa

in the lock walls, floor, gate sills, or in the gates themselves to admit water to the lock chamb

3-1
from the upper pool to fill the lock and to discharge water from the lock chamber to the lowe

pool to empty the lock, as illustrated schematically in Figure 3 .2.

For a vessel to proceed downstream through a lock, the ,lock is operated in the followin

sequence :

a. The emptying valves and lower and upper lock gates are closed .

b. The filling valves are opened to fill the lock and raise the water surface in the loc

chamber to the same elevation as the upper pool .

c. The upper lock gates are opened, and the vessel moves into the lock chamber .

d. The upper lock gates and filling valves are closed .

e. The emptying valves are opened to lower the water surface in the lock (and the vessel)

down to the level of the lower pool .

f. The lower lock gates are opened .

g. The vessel moves out of the lock chamber and into the lower pool .

Locks are sized for a design vessel or design tow (a towboat and barges), usually those

in use on the waterway, or adjoining waterways, at the time . However, if changes in equipmen

size can be anticipated in the future with the project, such changes should be given due

consideration in selecting lock chamber size. In the United States dimensions of barges and

towboats have changed little over the years, but the number of barges in a tow has increased a

towboat engine horsepower has increased .

Lock size affects the economic success of a waterway . If the locks are too small, traffi

may not develop as projected because of traffic delays in passing through the locks . If the lock

are too large, fixed and operating costs may be so large as to make the project uneconomical 

Uniformity of lock size from one waterway to another linking waterway is desirable to permit

through navigation . Careful consideration should be given to lock size and to the number o

locks at a given site. Two smaller locks may be more efficient in passing tows that one larg

lock.

Most locks on the Upper Mississippi River, constructed in the 1930s, have lock chambers

110- by 600-ft, and many tows using the river today are too large to pass through the locks i

a single lockage . The 15-barge tow at Lock and Dam 22, Canton, Missouri, shown in Figure 2.

will require two lockages . The 12-barge tow exiting Lock and Dam 15, Rock Island, Illinois, ha

been reassembled after double lockage, Figure 2 .1 . Larger tows, such as the 48-barge tow show

in Figure 2.2, are common on the Lower Mississippi River where open-river conditions prevail,

the channel is wide, and there are no locks .

"Lockage time," or "lock transit time," includes the time from when a tow or vessel begins

to proceed into a lock, is locked through, and exits the lock to the point where an opposite-boun

tow can enter the lock. Large tows must be slow and cautious when entering a lock because th

water displaced flows out of the lock along the sides of and under the tow . Filling and emptyin

times for a lock are designed to be as short as possible without causing excessive turbulence

surges, or cross currents in the lock chamber that might damage the tow or cause the tow to

damage the lock.

3-2
100

Upper pool

50

Distance (mi)

Figure 3.1 Spacing of navigation dams .

Lock chamber

I

Ilk_

Lower pool

	

EE

	

L ~-1

ose	

Filling valve open ; emptying valve closed. Lock

filled to upper pool level . Tow enters lock.

Upper gates

open

Upper and lower gates closed

I Open

ism

Filling valve closed ; emptying valve open.

Lock emptying to lower pool level .

El E] E3 El El El

=:Closed* :

pen ::-, -- . .. .

Filling valve closed ; emptying valve open .

Lock at lower pool level . Tow leaves lock.

Figure 3.2 How locks operate .

3-3

0

Lower gates

closed
c

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4.PHYSICAL FACTORS AFFECTING SITING OF NAVIGATION STRUCTURES

Physical conditions affecting affecting selection of sites for navigation locks and 

include the following .

4.1 Terrain

Stream gradient influences the number of dams required and the height and spacing 

dams. On a steep river, the pools will be deeper and shorter than on a river of flatter gradi

Bank heights limit the pool elevations (and dam heights) that can be used without permanent

flooding lands outside the normal channel limits .

The location of tributary streams may influence dam location because of the effects 

tributary flood flows on dam operation, deposition of sediment carried by the tributary in 

quiet water of the navigation pool above the dam, backwater effects along the tributary rela

to impoundment, and sediment deposition in the downstream reach of the tributary that co

increase local flood heights along the tributary. In general, a dam site immediately above a ma

tributary is better than a site immediately below the tributary.

The valley cross section should be wide enough for the locks and a spillway of adequa

length to pass flood flows without raising water surface elevations substantially . On alluv

rivers, if the channel must be widened significantly in the vicinity of the project to accommod

the required spillway length, problems with sediment deposition are likely to occur in the vicin

of the structure .

4.2 Geology and Soils

The best foundation material for a lock and dam is sound rock at reasonable depth, b

structures can be built successfully on other materials . Because geologic formations often v

radically along a river, moving a damsite a few kilometers upstream or downstream may resu

in safer and more economical foundation materials. Locks set on alluvial materials usual

require a pile foundation for structural stability .

River banks in the vicinity of a damsite should be relatively stable and permane

Recently formed banks are usually low and costly to protect . Leakage through the d

foundation may result in piping that threatens structural failure of the lock and dam, a

impervious cutoff walls may be needed . Impervious clay blankets upstream of the dam may

used to prevent loss of water by seepage from the upper pool.

4.3 Streamflow and River Stage

The spillway of a navigation dam is designed to pass the selected maximum desi

discharge, typically a lesser and more frequent flow than used for the design of high dams .

4-1
Minimum streamflow must be sufficient to operate the locks and to meet other water

requirements, such as leakage through the locks and dam, seepage from the pool and under the

dam, evaporation from the pool, and any required consumptive uses . If minimum flows are too

low to meet these requirements, special measures are needed to reduce seepage, recirculate

lockage water, or supplement low flows .

If large or rapid fluctuations in streamflow are typical, frequent use of spillway gates will

be required to maintain normal pool elevation .

Maximum water surface level determines the minimum height for gate piers on the

spillway crest and the clearance required for overhead structures, such as a bridge across the dam 

Piers must be high enough for fully-open gates to clear the maximum design water surface 

Navigation dams are designed to have minimum effect on flood levels through the pool, and the

backwater effect is generally limited to about one foot .

Minimum stage affects design of the stilling basin below the dam spillway . Minimum

pool elevation determines the extent of lands permanently flooded and, therefore, acquired for

a project. In a canalized river, the water surface in navigation pools is generally above natural

low-water elevations, and minimum pool level is the major factor determining the impact of the

project on the groundwater table and drainage of adjacent lands.

At the head of a pool, water surface levels fluctuate between normal pool elevation and

flood stages much the same as under preproject, open-river conditions . Depending on dam

height, stages just upstream of the dam may be permanently above natural flood levels.

4.4 Ground Water

Maintaining pool levels that .are higher than pre-project normal low river stages will

increase ground water levels in the vicinity .

4.5 Climate

The effects of humidity in areas of frequent or prolonged fog and the combination of heat

and humidity in the tropics must be given special consideration, especially in design and

maintenance of electrical machinery and the metal parts of structures .

Temperature range also may influence the type and design of operating machinery

selected . Ice can be a problem in cold climates if there is winter navigation, and special

measures may be required to limit icing on gates, trash racks, water intakes, and lock chamber

walls. Even without winter navigation, navigation structures in cold climates are designed to pass

large volumes of ice to avoid ice jams in the river .

4.6 Sediment

In a typical low-head navigation project, spillway gate sills are set very near river bed

elevation, Figure 4.1, and spillway gates are operated to pass flood flows with a minimum of

4-2
surcharge so that essentially open-river conditions prevail at high flows and the river can contin

to pass its normal sediment load.

Dams must be spaced along a river so that project depth exists in the upstream (head) 

of each navigation pool, Figure 4.2 . On alluvial rivers, some maintenance dredging typically 

required in such reaches, and frequently is necessary to contract the channel locally to mainta

sediment transport capacity at the heads of pools, Figure 4 .2 .

4.8 Environmental Resources

In designing a navigation project, consideration must be given to potential impacts 

water quality; flora, fish, and wildlife resources ; historical, archaeological, and paleontologi

resources ; and recreational opportunities .

4.9 Infrastructure and Commercial Resources

Urban development, highways, railroads, bridges, and pipeline and utility crossings m

need to be relocated or modified to accommodate a canalization project . Urban areas may 

affected. by changes in flooding pattern, rise in ground water levels, and pool levels that interf

with sewer outfalls. Problems in urban areas can be minimized by locating navigation d

upstream (rather than downstream) of urban areas where feasible or by using several low da

through an urban area rather than one higher structure .

Where there is extensive agricultural development in the river valley or mining in t

overbank, consideration should be given to two or more lower dams, rather than a single da

to reduce costs for land acquisition, relocations, and damages .
240

N

E.

c 220

0

w 200

0

IV'

_..

-4

2 4 6

Distance (100 ft)

Figure 4.1 Cross section, typical low-head navigation dam .

1

frJ , 1 r 1 1 J F

10050

Distance (mi)

0

1

8

10 12

Figure 4.2 Typical location of dredging and contraction work at heads of pools .

4-4
5.INLAND NAVIGATION CRITERIA

General design requirements for inland navigation channels and lock dimensions ar

governed by a number of factors, including types and volume of probable future tonnage, type

and sizes of vessels and tows in general use on connecting waterways, and developments on oth

waterways that may indicate the type and size of equipment likely to use the new waterw

during its project life . It is important that channel dimensions be adequate to handle the traffi

projected to use the waterway . U.S . Army, Corps of Engineers guidance (1980) for chann

dimensions states that

In determining the channel size, some of the basic criteria used are the sectional are

ratio, draft-depth ratio, and maneuverability requirements . Tests have indicated that t

resistance to tow movement in a restricted channel decreases rapidly as the sectional area rati

(ratio of the channel area to the submerged tow area) is increased to a value of 6 or 7 and the

decreases less rapidly as the ratio is further increased . Resistance to tow movement and pow

required to move the tow are increased if the draft is more than about 75 percent of the availabl

depth, particularly if the channel has restricted width, such as a canal or a lock .

Hydraulic conditions at sites tentatively identified for lock construction should 

thoroughly investigated in a general river model of the reach with the lock and dam structure i

place.

5.1 Minimum Dependable Depth

Dependable project depth is the minimum depth to be provided for traffic expected to us

the waterway ; it is not the submergence of the vessel or tow . Thus, a" 9-ft channel" provides 

dependable minimum depth of water of 9 feet . The majority of inland waterways in the Unit

States have authorized 9-ft channel depths, and because 9 feet is available, except during droug

periods, tows are loaded to 9 feet . The locks are designed to accommodate vessels of 9-ft draf

Minimum depth in a canalized waterway is usually referenced to normal pool elevatio

and pool levels should provide project depth and width over all obstructions in the river bed an

over the lower lock sill of the next dam upstream . However, in long, narrow navigation pool

where even low discharges cause an appreciable water surface slope, the water surface profil

at minimum discharge may be used as the reference plane rather than the pool elevation .

In a pool with only a short length of channel affected by an obstruction, excavation an

maintenance of project depth through that reach can result in reducing the required pool elevatio

The costs of such excavation should be evaluated in comparison with savings that could 

realized in the cost of lands, damages, and construction of a lower dam .

Navigation pool levels should be set to provide a fixed pool elevation with as litt

variation as possible because stable pool levels enhance reliability of the waterway and simpli

development of port facilities . Greater pool stability can be provided with higher dams becaus

high pools are less frequently affected by flood stages .

5-1
The U.S. Army, Corps of Engineers (1980) suggests the minimum channel widths presented in

Table 1 be used in straight reaches, with additional width provided in bends . Mathematical ship

simulation models are frequently used to evaluate the ease or difficulty of navigating through

specific reaches under various channel widths .

A wider channel is required in bends than in straight reaches because vessels and tows

take an oblique position with respect to the tangent of the radius of curvature (measured throug

the center of the tow) in transiting a bend, Figure 5 .2 . This angle a, termed the drift angle (o

deflection angle), varies with :

a. Radius of curvature of the channel.

b. Speed, power, and design of the craft .

c. Wind forces.

d. Whether the tow is empty or loaded.

e. The flow pattern .

The drift angle for downbound tows is larger than for upbound tows, and design of a channel for

one-way traffic is, therefore, based on the channel width required in bends for a downbound tow

Table 1. Recommended channel width

5-2

Channel width (feet)

Tow width (feet)

Two-way traffic One-way traffic

105 300 185

70 230 150

50 190 130
0

5.3Freedom from Hazardous Currents

Current velocities in the slack-water pools created by navigation dams are lower th

the natural river, and pool elevations are set sufficiently high to provide adequate dept

eliminate hazardous conditions at rapids . However, the locks and dams themselves may c

hazards for navigation because:

a. Tows entering and leaving a lock at low velocity have very limited steering p

b. Spillway releases can cause tows to break up and drift against spillway gates or 

upstream of the spillway.

c. In some cases, hazardous vortices or turbulence may occur in the upper or lower 

approaches due to operation of the filling or emptying systems.

Some restrictions may be required on operation of spillway gates near a lock to re

hazardous currents . Guide walls and guard walls are usually provided for some distance 

and below a lock to permit tows to move along the walls in safety and line up with the lo

Maximum velocities and maximum channel depth usually occur along the outer (con

bank of bends, and a lock aligned with the natural deep-water thalweg of the stream will usu

be the least expensive . Lock sites in sharp bends and where the structure would defl

substantial part of the flow from the deep part of the river should be avoided .

5.4 Minimizing Lock Transit Time

Lockages are time consuming and expensive for both users of a waterway and 

operators of the locks, and every effort should be made to minimize lockage time in a naviga

system. The time required for tows to pass through a lock for lockages in alternate direct

(bound upstream, bound downstream, bound upstream, etc.) includes :

a. The time a tow is operating at reduced speed in approaching, entering, and leavi

lock.

b. The time required to break up and reassemble tows made up of too many barge

pass through the lock in one lockage .

c. The time required to close the lower (or upper) lock gates.

d. The time required to operate filling (or emptying) valves .

e. The time required to fill (or empty) the lock chamber .

f. The time required to operate upper (or lower) lock gates .

g. The time required for tow to exit the lock chamber and reach a point where the 

bound in the opposite direction can enter the lock.

Low-lift locks are simpler to design and construct than high-lift locks, but more 

needed in a given river reach, and traffic delays are greater . Lockage time is a part of total 

time," and savings in trip time increases capacity of the waterway . Such savings ca

evaluated in monetary terms in the economic analysis . Lockage time can be minimized b

5-3
with adequate sight distance for safe steering .

b. Designing lock filling and emptying systems so as to minimize valve operating time 

c. Providing lock chambers of suitable size for traffic using the waterway to avoid the

need for double lockage of a single tow .

d. Minimizing the number of locks in the system .

Miter gates can be opened or closed in about one minute ; sector gates are operated more

slowly if there is filling or emptying around the gate .

5.5 Terminal Facilities

The location of future terminal facilities should be given careful consideration in planning

the location of locks and dams for a new navigable waterway . The deep, wide pool immediately

above a dam is favorable for development of harbor facilities ; however, the pattern of local traffic

should be evaluated . Locating a terminal near a lock, either upstream or downstream, may

require a large number of lockages for local traffic that will interfere with through traffic .

Factors to be considered in locating new terminals along a canalized waterway include :

a. Will the pool level be relatively stable?

b. Is there existing industrial development that could be served by the waterway?

c. Are there suitable areas nearby for industrial expansion and terminal development?

d. Are there connecting modes of transportation (railroads, highways)?
40 ft

rr

	

r

r

(a) One-way traffic

40 ft

Figure 5.1 Minimum channel clearance in straight reaches .

(U .S. Army, Corps of Engineers)

Tow

1050 ft R

b . Variation in drift angle and

channel width occupied by

downbound tows of

different lengths .

	

20 ft Tow

r

F

I

35 ft

Deflection angle a = 11.8•

Channel width w = 350 ft

a. Downbound tow (70 by 51

negotiating a bend with

low-velocity currents .

50 ft Tow 20 ft

r 1 ., /Z/

(b) Two-way traffic

Notes :

Radius of curve : 3

Degree of curvatur

Velocities : 3 ftlsec

Figure 5.2 Widths required in Bends . (U .S. Army, Corps of Engineers, 1980)

5-5
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6.1 Flood Stages

Low-lift navigation dams are usually designed to the minimum height required to pro

project depth over obstructive reaches of the river :

a. At low discharges, the normal pool level is almost horizontal and at an elevation 

to or somewhat above the low-water stage at the head of the pool .

b. At higher discharges, if the pool elevation remains fixed at normal pool level at 

dam, velocities, stages, and water-surface slope at the head of the pool will rise and more 

will be flooded, Figure 6 .1 .

c. The additional depth at higher discharges is not required for navigation, and da

due to flooding adjacent lands may be minimized by drawing down (lowering) the pool leve

the dam to where the water-surface profile through the pool provides only project depth 

controlling obstructions. Such operation is termed a "hinged-pool" operation and is discu

further in Appendix B .3 . The amount of permissible drawdown at the dam is determined by 

water-surface slope that would produce limiting velocities for navigation in the lower porti

the pool .

6.2 Drainage

The water surface elevation throughout a navigation pool is permanently above nat

low-water stage, Figure 6 .1, and for relatively high dams, stages at the dam may be permane

above the highest natural flood level . At the head of the pool, stage will fluctuate bet

normal pool level and flood stage in generally the same manner as under preproject conditi

This increase in stage throughout a pool may :

a. Interfere with the discharge of sewers, culverts, and tributary streams that forme

discharged freely at low river stages.

b. Result in deposition of silts or sludge in the pool that may block sewers or intakes 

raise the bed of tributary streams.

c. Cut off natural drainage paths, requiring rerouting drainage systems or pumping 

local runoff to enter the waterway .

d. Raise ground water levels, requiring additional agricultural drainage .

Many drainage problems can be minimized or eliminated by selecting dam sites downstream f

major drainage outlets and tributaries .

6.3 Water Supply Intakes

Navigation pools provide reliable depth at water supply intakes, and water quality i

important consideration . If a navigation pool is the source of water supply, sewer outlets sho

be located downstream of the dam . Special measures may be required to ensure that sedi

deposition will not block intakes .

6-1
Aeration provided by turbulent flow through spillways aids in maintaining the dissolved

oxygen levels required to support fish life and for aerobic decomposition of sewage . However,

immediately above a dam, where pools are relatively deep and velocities are low, wastes may

settle out resulting in anaerobic conditions . . Accordingly, navigation structures should not be

located downstream of major sewage discharge points. Where structures are located in an urban

area, consideration should be given to providing interceptor sewers discharging below the dam .

6.5 Vector Control

In some latitudes, stable navigation pool levels provide an ideal environment for mosquito

breeding, particularly if floating debris, dead brush, or aquatic vegetation accumulates in shallow

marginal areas . Where malaria is endemic, consideration should be given to fluctuating the pool

level about one foot each week in the mosquito-breeding period to strand mosquito eggs, larvae,

and pupae along the pool margin . A typical example of such an operation is shown in Figure

6.2 for the Wilson Project of the Tennessee Valley Authority. At Wilson, the pool level is drawn

down 1 .5 ft below normal pool elevation and refilled each week during the May-September

mosquito-breeding season .

6.6 Fish and Wildlife

Impoundment of navigation pools may inundate spawning areas, nesting grounds, and

habitat, and dams may block the movement of migratory fish . In designing navigation projects,

consideration should be given to recommendations of fish and wildlife specialists as to the effects

that various pool levels, dam locations, and operating procedures would have on fish and wildlife

resources.

If dams block migratory fish movement, mitigation measures, such as the following, may

be needed:

a. Fish ladders for fish to pass around dams .

b. Fish hatchery .

c. Management of fish spawning gravels .

Other mitigation and enhancement measures include :

a. Selective withdrawal of water from various depths in the pool to control temperatures

of downstream releases from high dams .

b. Reaeration measures to meet or improve dissolved oxygen levels required for fish .

c. Modified spillway release patterns to meet fishery requirements.

Stable pool levels can reduce the stranding of fish during low water periods in rivers of

highly varying discharge and can benefit wildlife having nests and dens near the shoreline .

6-2
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6.7Recreation

Impoundment of navigation pools often improves the recreational potential of a river a

creates new opportunities for recreation development, particularly where projects are located 

or near urban areas . Consideration should be given to including recreation areas and facilit

in navigation projects . However, it should be noted that there can be conflicts betwe

recreational and commercial boating on a waterway . Commercial tows have slow maneuver

and stopping capabilities and can be a hazard to recreationists .

6.8 Hydropower

The feasibility of hydropower development should be considered at all navigation da

Leakage through the locks and dam, evaporation and other water losses in the pool, and wa

required for lockages must be subtracted from total streamflow to determine the water availa

for power production . Except in the case of high-lift structures, the most suitable type of po

installation is a "run-of-river" plant that utilizes natural streamflow with essentially 

modification by storage .
Normal pool elevation,

low discharges,

Higher discharges, normal

S = 0 pool elevation at dam

Figure 6 .1 Effect of pool operation on water surface elevations .
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JAM FEB WAR APR WAY JUN JUG AUG SEP Oct NOV

Figure 6.2. Multiple-Purpose Reservoir Operation for Vector Control.,

Wilson Project, Tennessee Valley Authority .

(TVA Monograph 55, Engineering Data,

TVA Water Control Projects, 1980) .

6-5

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7.NAVIGATION DAMS

A navigation dam impounds water in a pool to provide navigable depth to the next 

upstream . The spillway or outlet works of such dams is designed to pass flood flows and 

regulated by gates to control outflows so as to maintain the pool elevation at an essenti

constant elevation except during flood periods . In addition to gated spillway bays, s

navigation dams include an uncontrolled concrete weir crest, as at some dams on the Red Ri

or low overflow embankments in the overbank, as at some dams on the Arkansas Ri

Navigation dams are of two general types : movable and fixed .

A navigable movable dam is a structure consisting of a number of wickets that can 

raised individually to impound a pool at low flows (when traffic uses a lock to pass the dam) 

lowered to the streambed to pass flood flows . During high-water periods, traffic can bypass 

lock and pass over the dam in the lowered position . Designs of wickets vary, but the structu

members supporting the damming surface are hinged to lie flat on a concrete sill at bed le

when the dam is open, Figures 7 .1 and 7.2 . Navigable movable dams are suitable only in spec

cases where the lift is relatively low, the bed is stable, and there are distinct non-flood and f

periods with river stages high enough for open-river navigation for a significant part of the ye

A fixed navigation dam is a structure with streamflow passing over the top of the d

through a spillway (either gated or ungated), or through tunnels . Fixed low-head navigation d

are of various types, ranging from the rock-filled timber cribs used in older projects to the 

gated concrete crests set at about bed level generally used today, Figure 7 .3 . The typical des

for the Arkansas River navigation project, shown in Figure 7.3, has piers on a broad-crested w

movable spillway gates, a stilling basin, and protective stone blankets upstream and downstr

of the dam to protect the river bed against scour . A similar spillway design was used for d

on the recently completed Red River navigation project, Louisiana . Design of the dam foundat

depends on the nature of foundation materials at the site . Design of the piers and operat

bridge depends on the elevation of high water and the size and type of gate and operat

machinery used .

7.1 Navigable Movable Dams

Navigable movable dams include a navigable pass for passage of tows without locki

A navigable pass must provide sufficient clearance width for the safe passage of traffic and mu

have sufficient depth for tows of design draft, including depth to allow for overdraft and 

squat. Model studies indicate that a navigable pass should have a minimum cross-sectional ar

2.5 times the area blocked by a loaded tow . Current direction should be aligned normal to 

axis of the pass, and velocity through the pass must be low enough to permit passage of 

upbound loaded tow of the horsepower operating on the waterway . Navigable pass widths 

Corps of Engineer projects range from 200 ft on the Ouachita River to about 1200 ft on the O

River.

The Corps of Engineers still operates a few dams with older wicket gate designs, such 

shown in Figure 7.1, on the Ohio and Ouachita Rivers and the Illinois Waterway, but su

designs are no longer being constructed .

7-1
Canalization of the Ohio River was initially completed in 1929 with 50 low-lift locks and

dams, all with wooden wickets and a 110- by 600-ft lock chamber . Replacement of those

structures with 19 locks and dams was initiated in 1954 . Eighteen of the replacement structures

are high-lift fixed dams with 1200-ft locks . The last, and most downstream, structure is Olmsted

Locks and Dam currently under construction about 16 miles above the confluence of the Ohio

and Mississippi Rivers, replacing the old Ohio River Locks and Dams 52 and 53 . Olmsted is the

only replacement dam on the Ohio River that uses wickets, Figure 7 .4. A unique centrallycontrolled hydraulic lifting mechanism was considered to raise the 220 wickets for the Olmsted

project, Figure 7 .2 . However, a manual operating system from boats is planned at this time . The

Olmsted wickets will be 25 .5 ft high and 9 .2 ft wide ; wooden wickets at the existing dams are

about 14 ft high and 4 ft wide . At Olmsted, the wickets will be placed on a concrete sill with

a baffled stilling basin with a sloping endsill, Figure 7 .2 .

7.2Spillways

Spillways for low-lift navigation dams are usually designed with sufficient flow capacity

to limit the backwater effect of the structure to about one foot for the project design flow . Where

raising flood levels more than one ft is locally acceptable, as for some dams on the Red River,

it may be more economical to obtain additional flowage easements and use fewer spillway gates,

as discussed in Appendix B . Such spillways for low dams are usually of the broad-crested type

because flow over the spillway is influenced by tailwater levels for most operating conditions 

Spillways normally are set near the river bed to maximize capacity and reduce backwater

and extend across the entire river. The gate sill and stilling basin may either be level across the

channel or set at different elevations across the stream to conform to the natural river cross

section, preserve natural flow distribution across the channel, and minimize obstruction of the

flow area when the gates are fully open, Figure 4.1 . The spillway at Lock and Dam 4 on the

Arkansas River was set at two elevations, with the high section at the opposite bank from the

lock (where deposition occurred prior to project construction) . After 15 years of operation, the

benefits of the stepped crest are considered negligible, and a level crest elevation would be

recommended (Corps of Engineers, 1987) .

Spillways for navigation dams sometimes include uncontrolled overflow crests, depending

on local conditions and optimization studies analyzing the costs of providing additional spillway

gates needed to pass the design flow with about one foot of swellhead at the structure vs the

combined costs of fewer gates and flowage easements needed due inundation of additional lands

upstream . Also, it is sometimes desirable to provide additional flow capacity on the overbank

to minimize backwater effects . Overflow embankments on the overbank are set as close to the

overbank ground level as feasible to best utilize flow capacity of the overbank, and such

embankments should be at least three ft above the navigation pool to allow for variation in pool

levels, wind setup and wave runup.

On rivers where low dissolved oxygen levels during low-flows present a water quality

problem, special measures may be needed to reoxygenate water discharged over the spillway 

At Locks and Dams 4 and 5 on the Red River, Louisiana, one spillway bay has a hinged crest

7-2
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discussed in Appendix B .4 . Turbulence on the baffled chute increases dissolved oxygen leve

Hydraulic models of spillways are employed to determine :

a. Minimum crest length in the direction of flow and shape of the downstream face 

the sill to ensure that there is no separation of the nappe from the sill and no undulating jet act

for all partial gate openings for the expected range of pool levels and various stilling ba

elevations, and no serious negative pressures on the gate sill .

b. Optimum shape of gate pier nose .

c. Spillway rating curves .

d. Stilling basin performance curves for the expected range of tailwater levels .

e. Riprap requirements downstream of the stilling basin.

Low-head navigation structures have four possible flow regimes, as shown in Figure 7 

depending on the effects of gates, tailwater elevation, and flow through the structure.

7.3 Spillway Gates

Various types of spillway gates are used, depending on spillway operating requiremen

and costs. If more than one type is suitable for a particular case, selection is based on co

Where passage of ice or debris downstream through the dam requires wide gate opening

submergible gates (roller, tainter, or vertical lift gates) are used . These gates can be raised 

normal operation, with discharge under the gates, but can be submerged below upper pool lev

to pass ice or debris over the top. If the range of stage is large, vertical lift gates may be mo

economical than tainter gates with very long arms . Where passage of ice or debris is no

problem, either tainter gates or vertical lift gates are generally used . Hinged crest gates a

baffles on the downstream spillway face were used at two dams on the Red River Waterw

where low dissolved oxygen levels were a problem in extreme low-flow periods . The hing

crest gates draw water from the warm surface level of the pool and discharge it onto the baffl

spillway face where turbulence oxygenates the flow .

Tainter gates are a segment of a cylinder mounted on radial arms that rotate on trunni

embedded in piers on the spillway crest, Figure 7.6a . The gate consists of a skinplate ove

system of beams that transmits the water load on the gate to the radial supporting arms . T

gates may seal against the top of the sill, or may lower past the sill for passage of water (and i

and debris) over the top of the gate, Figure 7 .6b. Gates designed for submergence have t

skinplate extended over a rounded crest and down the lower face of the gate . Tainter gates 

raised and lowered by chains or cables at the ends of the gates and are less resistant to torsi

than are roller gates, but for short spans they are less costly than roller gates of comparab

height. It is essential that these gates be designed to be raised above the design flood flow li

so as not to raise flood levels and not to endanger the gate. Clearance is usually from one to 

ft above the probable maximum flood. It is desirable, but not mandatory, that the trunnions 

above high water, and trunnion elevation is set above most flood levels, so that submergen

occurs only 5 to 10 percent of the time . Gate vibration has been a problem when tainter ga

operate ' under submerged flow conditions at some dams . Tainter gates have be

7-3
designed with heights in the range of 75 ft and lengths of up to 110 ft . Where extremely lon

arms would be required, it is not practicable to use tainter gates .

At Marseilles Lock and Dam on the Illinois River, non-submersible tainter gates on the

spillway were replaced by submersible gates in 1987 to skim ice and debris over the top of th

gates with much smaller discharge than required to draw the material under • non-submersibl

gates. The gates, Figure 7 .7a, were model tested with two spillway profiles, Figure 7.7b, and tes

data indicated that the crest shape had little or no effect on discharge characteristics of th

structure . The data indicated that the Type 1 crest would be unstable due to vibration . . Th

Type 2 crest was adopted, and the gate was modified to extend the gate end shields near the

piers, Figure 7 .7c, to decrease the clearance between the shield and pier from 4 inches to 0 .

inches; the gate to sill clearance of 1 inch was maintained . The gates have operated for severa

years without vibration problems .

Roller gates are metal cylinders with ring gears at each end that travel on inclined metal

racks on the piers, Figure 7 .8 . The roller gate is braced internally and acts as a beam to transmi

the water load to the piers. Water, ice,, and debris can be passed over the gate, and the gate ca

be raised to pass water under the gate . Roller gates are raised and lowered by a chain around

one end of the gate operated by a hoist mounted in the pier . Water can be admitted to or

released from the interior of the gate to change the gate's buoyancy, and the rolling movemen

of the gate and limited friction contact at the seal make roller gates easy to operate . They have

been designed with heights up to 30 ft and lengths up to 124 ft on pile foundations and 150 f

on rock foundations .

Vertical lift gates have a skinplate over horizontal girders that transmit the water load to

the piers, Figure 7 .9. High piers are required for the gates in the fully-raised position above high

water level . To minimize gate vibration, the gate lip in contact with the flowing water is kep

as narrow as possible . Vertical lift gates are mounted on wheels or rollers to permit movement

under water load, and are raised by chains at both ends, with the entire weight carried by th

chains . The gates move vertically in slots in the spillway piers and seat on steel sills mounte

flush on the spillway crest. Vertical lift gates have been designed for heights up to 60 ft and fo

spans in excess of 100 ft . When very high gates are required, a vertical lift gate may be designe

in two or more horizontal sections (leaves) to reduce the required hoist capacity, reduce pie

height, reduce damage to fingerlings passing downstream, facilitate passing of ice and debris, or

simplify design of the ogee crest.

Hinged crest gates, or flap gates, of the type used on some recently constructed spillways

on the Red River waterway, can be used to pass warm water from the upper level of the pool or

to pass debris and ice. Hinged gates consist of a skinplate that transmits water pressure to a

internal system of girders . They are operated by a hydraulic piston and rotate about a hinge on

the weir. crest and form a part of the crest when in a lowered position, Figure 7 .10. The hinge

crest gate used at dams on the . Red River waterway is described in Appendix B.4 .
c

The nose of ogival spillway piers on the Arkansas River project were shaped so that pie

radii meet to form a 90-degree angle at the leading edge of the pier, Figure 7 .3c, and a structur

steel angle was embedded into the nose to protect the piers from damage when hit by loo

barges. It has been found that the sharp steel angle tends to rip open barges, causing them t

sink upstream of the piers. The steel nose edge has proved very efficient hydraulically fo

uniform gate openings, but when there is a difference in gate settings, it causes a separation o

flow from the face of the pier on the side passing the greater discharge . An ogival shape wi

rounded leading edge is recommended (Schmidgall, 1995) .

7.5 Ice

In cold climates, such as on the Upper Mississippi River, traffic ceases for several mont

during the winter period. However, the locks and navigation dams are operated throughout th

winter to pass winter flows and ice . Passing ice is handled in different ways at the vario

projects . The primary factor controlling ice passage appears to be velocity of the ice as 

approaches the structures . To maintain pool levels during periods of low flow, it is preferab

to pass ice over the top of the spillway gates or through the lock .

7-5
Pull to trip-,-

Pull to raise

Resultant

Wicket

N I-I __

(a) Wicket dam

(c) Chanoine-Pascaud twoposition steel wicket

Wicket trips

automatically when

load rises above

trunnion

(e) Bear-trap dam

(b) Chanoine wicket dam

(d) Bebout self-tripping wicket

Solid upper leaf

Buoyant lower leaf

Water released to

Water pressure from lower pool lowers dam

upper pool raises

and holds dam

Figure 7 .1 Movable dams . (U .S. Army, Corps of Engineers, 1952) .

7-6
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.EL 254

b. Plan

18222

a . Section through wicket gate and weir

EL 274.56

.EL 271

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~ .33.78 .14.4' 32 771

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7.0,

radius

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.7

c. Section A -A

T

Figure 7.2 Navigable movable dam (wicket gates),

spillway and stilling basin, Olmsted Locks and Dam, Ohio River.

7-7

21 .58 

TI El 
cin

1

G

a

d

(a) Typical section

a

35.3 ft27 ft 60 ft

(b) Details of spillway

Figure 7.3 Typical non-navigable movable dam (gated spillway),

Arkansas River. (Grace, 1965)

020

Scale (ft)

Stilling basin

Baffle blocks

1	 -K--End sill

0.133H 

0.267H 

OgivaiSemicircular

(c) Pier nose shapes
C

C

Figure 7.4. Olmsted Locks and Dam, Ohio River.

7-9
FREE UNCONTROLLED FLOW

7-10

SUBMERGED UNCONTROLLED FLOW

FREE CONTROLLED FLOW

SUBMERGED CONTROLLED FLOW

Figure 7.5 . Possible flow regimes, low.-head navigation weirs .

(Corps of Engineers, 1987)
a

C-)"

a. Tainter gate on spillway crest (downstream view) . Gate is operated

by a chain and travels in groove on pier face,

Fort Randall Dam, Missouri River.

b. Tainter gate seals . (U.S. Army, Corps of Engineers, 1952)

Figure 7 .6 . Spillway tainter gates.

7-11

Tr
PIER EXTENSION-.-

/ SPLASH

7 SHIELD EACH

END OF GATE

ICE SHIELD

SEE DETAIL '8'

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a . Details of submersible tainter gate .

15'•I 'R

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TYPE 2 DESIGN CRESTEL sa7

	 1.51 1 1 25 I

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-I

b . Spillway and stilling basin for submersible tainter gate.

Alternative spillway crest shapes tested .

Figure 7.7 Submersible tainter gate, Marseilles Lock and Dam, Illinois River .

(Cooper, 1989)

7-12

EL sole

SCALE

-EL 4686 0

IS"MINIMUM

OR CARRIED

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c. Marseilles model; flow under submersible gate . Gate open 7 ft

Figure 7.7 Submersible tainter gate, Marseilles Lock and Dam, Illinois River .

(Cooper, 1989)

(a) (b) (c)

Figure 7.8 Roller gates . (U.S. Army, Corps of Engineers, 1952)

7-13

(d)
(a) Section

(6) Plan

Figure 7.9 Typical vertical lift gate .

Figure 7 .10 Typical hinged (flap) 
8.NAVIGATION LOCKS

8.1 General Considerations

A

C-)

Lock Location . In canalized waterways, the navigation lock is usually located near o

bank at the end of the dam so that :

a. Spillway length is maximized .

b. Adverse effects of spillway currents on river traffic is minimized .

c. Pilots can approach the lock by traveling along the protected area near the shore .

In canals, the lock often occupies essentially the entire canal width and acts as the dam . Typic

layouts for locks are shown in Figure 8 .1, and a general layout of a low-lift navigation lock an

dam is shown in Figure 8 .2 .

In general, where two locks are provided (twin locks of equal size or a main lock an

smaller auxiliary lock), it was customary to place the locks side by side, with a common cente

wall, as shown in Figure 8.1 . However, at the new Melvin Price Locks on the Mississippi River

replacement for Lock and Dam 26, the two locks (a 1200-ft main lock and 600-ft auxiliary loc

are separated by a 350-ft spillway section with two gate bays, Figure 8 .3 The 350 ft separati

extends from the inside face of the land lock to the inside face of the river lock and was provide

for more efficient use of the lock and higher traffic capacity . The separation distance was base

on operation studies and recommendations from towboat pilots for the minimum distance betwee

locks with two tows passing, one tow approaching the locks and a second tow departing .

Pilots must have a clear view of the lock entrances because momentum of a tow whe

it is slowing down is difficult to control due to inertia and low power. Minimum sight distanc

in a lock approach of one mile is usually sufficient for safe operation, permitting tows to alig

with the lock before reducing speed . Model studies are conducted of tow operation in loc

approaches to investigate potential operation problems, and the views of rivers pilots are take

into consideration .

The exact location of a lock depends on such factors as :

a. Configuration of the river reach.

b. Shape of the channel cross section .

c. Hydraulic conditions at the site .

d. Bank elevation and stability .

e. Foundation conditions.

Straight reaches of river are more desirable sites for navigation locks and dams than bend

because they are easier to navigate . However, straight reaches of alluvial rivers often tend to b

unstable, and adequate depth in the downstream lock approach may be hard to maintain .

Adverse cross currents from spillway discharges also may present problems to traffic i

the lock approaches . A pair of locks located on the deep side of a bend, Figure 8 .4, may blo

8-1
so much streamflow that spillway operation results in undesirable currents in the upper loc

approach . The upstream guide wall, as well as the lock itself, can adversely affect flo

conditions . Cross currents in crossings may also interfere with tows approaching a lock .

Cofferdams for Construction . Navigation structures are usually constructed in a serie

of stages so that river flows can be passed during construction and in some cases, such as during

construction of replacement for Lock and Dam 26 on the Mississippi, tows can continue to use

the river during construction . Consideration must be given to potential problems with cofferdam

during the construction period when evaluating alternative sites for locks and dams and also when

evaluating alternative schemes for cofferdams at a particular site, including :

a. The number of cofferdam stages and the extent of each stage . Typical cofferda

layouts are shown in Figure 8 .5a . Twin 1200-ft locks at the Smithland project on the lower Ohio

River (replacement for Locks and Dams 50 and 51) are shown under construction in a cofferdam

in Figure 8 .5b .

b. Passing navigation traffic through the construction reach while cofferdams are in plac

if there is commercial navigation on the river prior to project construction .

c. Seepage into the dewatered area inside the cofferdam and related pumping

requirements.

d. Frequency of flow at which the cofferdam would be overtopped and flooded .

e. Difficulties associated with passing high flood flows through the construction are

while the cofferdams are in place, including estimated scour with different cofferdam

configurations.

f. Cost of alternative cofferdams schemes, including the cost of dewatering, cleanup, an

repair associated with overtopping of the cofferdam .

The three-stage cofferdam scheme for construction of the replacement locks and dam fo

Lock and Dam 26 on the Mississippi River is shown in Figure 8 .6 . Construction began from th

west bank of the Mississippi River, with the Stage I cofferdam which enclosed 6 .5 spillway bay

The Stage II cofferdam enclosed the 1200-ft lock riverward lock and two half gate bays (one-hal

gate bay on each side of the lock), and the Stage III cofferdam enclosed 1 .5 gate bays and. t

600-ft landward lock.

For construction of Dardanelle Lock and Dam on the Arkansas River, 3-stage and a 4

stage cofferdam schemes were considered . The 4-stage plan, Figure 8 .7, used larger diamet

cells and required less sheet piling than the 3-stage plan . It was cheaper to construct and

therefore, was selected .

Navigation projects can sometimes be constructed off-channel, as was done for locks a

dams on the Red River where 36 cutoffs were constructed to realign the channel for navigation 

(The 280-mile navigable reach was shortened 50 miles, or 18 percent .) Locks and dams wer

constructed on the alignment of cutoffs that were part of the overall plan for stabilization an

rectification of the future navigable channel. After completion of the locks and dams in the dr

connecting channels were excavated to the river, the old river channel was closed off at th

upstream end, and the river was diverted to the new alignment through the cutoff, Figure 8 .8 

8-2
CD

Access to Construction Site . Ease of access to the project site affects project cost

construction and also for operation and maintenance after project completion . For project

remote areas, the cost of constructing access roads may be a large part of total project co

Availability of waterborne and overland transportation systems and power facilities all af

project costs.

Availability of Construction Materials. The availability of construction material

sufficient quality and in sufficient quantities for project construction within economic dista

of the construction site must be investigated in the planning process . When materials suc

coarse and fine aggregate and protection stone are not available locally, they must be brought 

the site at higher cost .

8.2 Lock Design Criteria

Lock Size and Number of Locks. Consideration of the types of navigation equip

projected to use the canalized waterway, type and volume of projected traffic, and econo

studies including project costs and estimated navigation benefits all influence :

a. Lock chamber size .

b. Optimum filling time (whether or not a fast filling and emptying is needed) .

c. Whether or not one or two locks are required at each dam .

In some cases, the size of tow that can be physically accommodated at critical chan

points along a canalized river may limit the size of tow using a lock and size of lock chamb

Standard usable lock dimensions in the United States are given in Table 2 .

Table 2. Usable Lock Dimensions (feet)

Where a single lock is used, traffic will be interrupted when the lock is closed 

maintenance or repair; however, this may not be a major problem if traffic is highly seasonal 

8-3

Width Length

84 400

600

720

800

1200

110 600

800

1200
maintenance can be scheduled in the off-season . Two locks increase reliability of the syste

If one lock is out of service (due to an accident or for maintenance) some traffic can contin

to use the one operable lock .

If economic studies do not justify construction of two locks initially, it may be desirab

to include some works (such as the upstream lock gates) in initial construction to minimize cost

of adding a second lock in the future .

Lock Lift . Lift is one of the first and most important design criteria to be established 

planning a canalization project . Maximum lock lift is the vertical distance from the upper po

normal water surface elevation above the lock to the low-water surface elevation below lock 

is the range of water surface levels in the .lock chamber Figure 8 .9 . The lock lift and upper po

elevation must provide adequate and safe depth for navigation over all obstructions througho

the pool and over the lower gate sill of the next lock upstream . The cost for one high-lift lo

may be less than the combined cost of two low-lift locks of equal total lift, but the design 

usually more complex .

Lift is the major factor governing the type of filling and emptying system used for 

particular lock, and locks are generally classified by lift as follows :

Low-lift lockLess than 30-ft lift

Intermediate-lift lock 30- to 60-ft lift

High-lift lock More than 60-ft lift

All new high-lift locks in the United States are based on either Lower Granite or Bay Spring

manifold systems, Figures 8.19 and 8 .39.

8.3 Lock Types.

Locks are of various types, and the design used at a particular site is usually determin

by foundation conditions and costs. If there are no unusual foundation conditions, gravity loc

are usually the most economical type to design, construct, and maintain due to simplicity o

design, the relatively small amount of skilled labor required for construction, and lo

maintenance costs of the thick sections . Reinforced concrete lock wall design is used for wal

at gate bays and approach walls and is similar to design of reinforced concrete retaining wal

Gravity walls are reinforced at thin areas, and the dry-dock lock is a reinforced-concrete structur

Approach walls, abutments, the area around culverts, filling and emptying laterals, and other par

of most modern locks are of reinforced concrete .

Gravity mass concrete locks can be designed for soil, rock, or pile foundations and hav

few structural limitations as to height or lift . Base width of walls must be sufficient to preve

overturning and sliding and overstressing the foundation . Top and intermediate widths of wal

must provide a section to withstand the wall stresses and provide space for filling and emptyi

systems, anchorages for gates, operating equipment, temporary closure structures, and oth

machinery. Disadvantages of gravity structures include loads that may be heavy with respect t

8-4
0

c.

supporting capacity of the foundation materials and the possibility of unequal settleme

adjacent or opposite monoliths that may result in misalignment or damage of movable struc

and operating machinery .

One of the newer innovative designs used on the Kanawha River places the fillin

emptying culverts in the lock chamber floor and uses roller-compacted concrete for lock ch

walls between the gate monoliths . This is discussed further in Section 11 .

Dry-dock type reinforced concrete locks are used where foundation conditions pre

use of a gravity design and where the use of a pile foundation is not practicable . The 

consists of relatively thin lock walls constructed integrally with a thick floor slab, designed t

together as a monolith, each being heavily reinforced to distribute loads . The dry-dock type 

can be unwatered for inspection and repair without fear of a blow-out and loss of founda

material ; however; adequate provision must be made to offset the buoyancy effect of 

structure .

Steel sheet piling locks are a combination of sheet piling with one or more other typ

construction. For temporary locks and waterways that do not warrant costly construction, s

sheet piling can be used for the walls between gate bays and for the approach walls . The p

is driven in a straight line, and any offsets along the face of the wall can be eliminated by 

timber fenders bolted to the piling at levels where the tows usually rub against lock walls . 

of this type have a relatively short useful life of about 15 to 25 years .

Combination-type locks combine several types of construction in one design. Whe

considerable amount of sound rock must be excavated, a layer of reinforced concrete ma

constructed adjacent to the vertical face of the rock to form the lower portion of the lock w

The concrete is anchored to the rock by steel dowels grouted into drilled holes . The u

portion of the walls is of gravity design .

For low-lift projects and in canals, levees may form part of the lock walls between 

bays. Walls of concrete or sheet piling can be constructed to a height to accommodate navig

a large percent of the time, but the gate bays, gates, and levees should be built to abov

maximum stage at which lockage is provided. When the walls between the gate bays 

overtopped, the levees and gate bays would maintain the pool elevation .

8.4 Lock Depth and Lock Floor

Locks fill and empty through a system of intakes and culverts upstream of the upper 

gate in the lock walls or upper gate sill ; culverts in the lock walls ; ports in lock chamber 

or on the lock floor; and emptying systems downstream of the lower lock gate .

It is desirable that lock filling time be as short as possible to minimize delay and cos

tow operators . However, there is some turbulence associated with the filling operation, and 

lock must be deep enough to provide a "cushion" of water over the filling ports to da

turbulence so that tows are not damaged and stresses in the hawsers (lines securing tows to 

lock walls) are within acceptable limits .

8-5
Depth provided in the lock chamber and over the lock gate sills depends on the type a

size of vessels and tows using the lock . Lock depth is the usual dimension governing overa

lock design, and is usually determined by design requirements for the filling system . The s

elevation may govern the lock floor elevation in some cases because the floor should be at lea

2 ft below the sill for operation and maintenance . For a side port system, the required cushi

depth over the ports usually controls . For bottom lateral and longitudinal culvert systems, the t

elevation of the bottom culverts may control, as they should be no higher than the top si

elevation.

Where foundation materials are erodible, such as sand and gravel, the concrete lock flo

is usually subject to downward pressures when water in the lock is at upper pool level and 

upward pressures when it is at lower pool elevation or when the lock is unwatered . Accordingl

the lock floor must be designed to withstand uplift due to hydrostatic head or relief wells mu

be provided . On alluvial streams, a line of steel sheet piling is sometimes driven around t

perimeter of a lock under the walls and sills to stabilize the foundation material and preve

movement of material out from under the lock walls .

For locks excavated in rock, a concrete floor may not be necessary if the culverts a

ports are located in the lock walls .

8.5 Lock Gates and Sills

Lock gates operate on sills, as shown schematically in Figure 8 .9 . Miter, roller, sect

tainter, and vertical lift gates are used as lock service gates, and each type has . spec

characteristics that make it the most suitable for any given site . Design of the gate sill vari

with the type of lock gate used, and deeper depths over the sill increases locking efficiency .

Miter gates are the most widely used type of lock gate on inland waterways in the Unite

States and are the only gates that cannot be operated (opened and closed) with a differential he

upstream and downstream of the gate . Other gate types can be used as both lock service gat

and for filling or emptying the lock and can be opened or closed to any position and held at t

position . Miter gates and miter gate operating machinery are designed to be under comple

control of the gate operator during opening and closing operations, to remain completely clos

when in the closed position, and to remain completely open and in the gate recesses when ope

Lock gates are designed for a static hydraulic load and for a temporary hydraulic lo

which may either add to or decrease the static head and, in extreme conditions, may produc

reverse head . Reverse loads almost always occur as a result of temporary conditions and are 

very short duration, except at tidal locks . Most frequently, reverse heads result from tempora

lock overfilling or overemptying due to the momentum of water moving in the culverts, and t

is generally the most serious temporary loading condition . Loading conditions are as follow

a. The maximum static hydraulic load on the upstream gate is the load due to differen

in water surface elevation of the maximum upper pool and the gate sill elevation .

8-6
C

0

The maximum static head on the downstream gate is the difference in elevation

between the maximum upper pool and the minimum lower pool .

c. Temporary hydraulic loads on gates can be caused by wind waves, seiches, su

waves from propeller wash, ship waves, and tidal action .

d. Temporary head reversal can cause miter gates to be briefly forced open slightly 

then slam shut, possibly damaging the gates .

Davis (1989) suggests the following guidance for evaluating temporary hydraulic lo

a. Use a temporary hydraulic load of 2 .5 ft for durations greater than 30 sec for d

or temporary reverse heads no greater than 2 .5 ft. This is a minimum value and applie

structural design of all gates, gate leaves, and operating machinery except miter gate opera

machinery.

b. Use a temporary hydraulic load of 1 .5 ft for durations exceeding 30 sec as 

minimum value for design of miter gate operating machinery.

c. Do not use miter gates where a temporary reverse loading significantly greater 

2.5 ft can occur for more than 30 sec .

d. Because overfilling and overemptying can occur on every lock operation, g

operating procedures should be designed to reduce potential reverse heads to nondamaging val

as by starting closure of the filling valves before the lock chamber is full . Automatic cont

can be designed so the valves will be about 95 percent closed when the lock chamber is fu

Lock gate sill elevations are set with relation to normal water surface elevation in 

adjacent pool, and gate sill elevation controls the draft of tows that can use a lock. For hin

pool operation, the upper sill must be low enough to provide adequate depth when the poo

hinged. Because of the difference in pool levels and lock lift, the upper gate sill elevatio

always higher than the downstream, and the downstream gates are always much higher than 

upstream gates, Figure 8 .9 . For example, Bay Springs Lock on the Tennessee-Tombig

Waterway has an 84-ft lift, and the upper gate sill is 75 ft above the look floor elevation, Fi

8.10, while the lower gate sill is at the same elevation as the floor.

Greater additional depth is provided over the downstream sill than over the upstream 

because a tow that fills the width of the lock chamber will squat several feet on entering the 

and may strike and damage the sill unless sufficient clearance is provided . Sill elevations 

determined by taking into consideration future development of navigation carriers and poss

degradation downstream of the lock . To provide greater clearance at the time of construc

usually does not increase initial project costs materially, but to provide it later might req

temporary closure of the waterway to traffic and costs could be excessive .

As a tow enters a lock, the water displaced by the tow flows out of the lock cha

between the bottom of the tow and the lock sill, and considerable space is required between 

bottom of the barges and the sill. When the last water displaced runs out, there is a sudden 

in resistance to the tow's entry into the lock, and if the tow is not at a dead stop, inertia will 

it forward into the upper sill or into the upper lock gates . Towboat captains are aware of 

phenomenon and keep their entrance velocities within safe limits . Operation is easiest, sa

and least time consuming with greater sill and lock chamber depths . Safety considerations 

8-7
members of the towing industry .

Under-tow clearance for optimum filling time, would be, a 23-ft lock chamber depth, o

a depth/draft ratio of 2 .5 . All Corps of Engineers 110-ft locks constructed since 1970 have a si

depth to draft ratio of at least 1 .7 (that is, 6 feet of under-tow clearance for a , 9-ft channel) 

greater. Ideally, depth over the sill of twice the tow design draft (18-ft depth over the sill for 

9-ft channel) should be available 95 percent of the time, and minimum clearance of 1 .7 times t

draft should be available 100 percent of the time . Most locks have 1 or 2 ft less depth over t

sill than in the lock chamber . In cold climates, such as along the Upper Mississippi River, i

accumulates on the bottom of barges ; six to eight ft of ice accumulation is not uncommon . T

downstream sill should not be more than 3 ft above the chamber floor as there is not mu

difference between the cost of one foot of sill height and one foot of lock gate height and greate

clearance over the sill increases safety.

All gate sills must resist lateral forces, consisting of both earth and hydrostatic pressur

from the bottom of the gates to the sill foundation. Often ports for culvert filling and emptyi

systems . and crossovers for various utilities are located in the gate sills .

Miter Gates. Miter gates consist of two gate leaves, each rotating on a vertical axis i

a recess in the face of the lock walls. When open, they are recessed in the lock walls and ar

flush with the face of the wall, Figure 8 .11. When closed, the stainless steel mitered edges of t

two leaves meet at the center line of the lock, and the gates are angled slightly upstream wi

respect to the lock walls so that upstream water pressure contributes to keeping the gates tight

closed and minimizing leakage . The steel gates have a girder framework covered by a skinplat

on one or both sides . They are designed with sufficient rigidity so that they do not twist 

become warped when rotated through the water.

Tainter Gates, . Tainter gate sills are of two types with respect to loading. One, whi

merely provides a sealing surface for the gate and a top surface to fit spillway characteristics, i

used only for narrow lock chambers where the entire gate load is transferred to the lock wal

through the end trunnions as at St. Anthony Falls, Figure 8 .12 . The second type 

used for wide lock chambers where end and intermediate trunnion arms transfer their loads t

trunnion castings anchored to buttresses attached to the sill . The sills are generally higher th

the lock floor area where the gates swing open so that any debris on the floor of the lock wi

not interfere with gate operation, Figure 8 .9.

Sector Gates . Sector gates, shown in Figure 8 .13, are used as lock gates where revers

of head occurs for significant periods of time, for example at a location affected by tidal acti

where the downstream water level is sometimes higher and sometimes lower than the upper poo

Sector gate sills are primarily to form sealing surfaces for the gates when closed and sometime

to provide rolling tracks to carry a portion of the dead weight of the gates .

Lift Gates . Lift gate sills provide a sealing surface and act as a spillway weir .

Emergency Closure Sills. Emergency closure sills provide a sealing surface for suc

8-8
C

0

structures as emergency gates, bulkheads, and so on that are provided to stop flow throug

lock chamber if the service gates become inoperative and to close off the lock chamber to pe

unwatering for periodic inspection and repair. Emergency closure sills are often outside 

intake and discharge ports of the filling and emptying system so that the ports and filling 

emptying system can be unwatered for inspection and repair . Bulkhead sills do not resis

part of the bulkhead lateral load, and the sill is designed only to support the weight of 

bulkheads and hydrostatic pressures below the bottom bulkhead unit. The bulkhead-type clo

provides a positive seal in flowing water without requiring the assistance of a diver at the to

the sill during installation . Emergency closure facilities are discussed further at the end of 

section.

8.6 Lock Walls

Lock walls are designated by location and purpose . For a single lock, walls 

designated as either land river wall . For two locks side by side, the dividing wall is design

as the intermediate or middle wall. Wall designations by purpose, shown in Figure 8 .9, ar

a. Lock chamber walls.

b. Upper gate bay walls .

c. Lower gate bay walls .

d. Culvert intake walls .

e. Culvert discharge walls .

f. Upper and lower approach walls (guide walls and guard walls) .

Lock walls always resist part of the gate thrust, and provision must be made to abs

these loads in the walls as well as to provide sufficient space for operating machinery.

The height of lock walls above pool elevation depends on the stage and flow at wh

navigation ceases, the importance of the waterway, and the value of uninterrupted transportat

during high stages as well as on characteristics of the waterway, type of dam, type of lo

balance between initial construction cost and maintenance cost, and other factors . On ma

waterways, walls are set at sufficient height so that traffic is interrupted only by infrequent f

flows because if published traffic schedules cannot be maintained by shippers during most of 

year, or if schedules are subject to numerous interruptions because locks are out of servi

projected use of the waterway may never develop.

During the 1993 flood on the Upper Mississippi River, locks were out of service fo

total of 77 days (three different closures) ; seven locks were under water. Costs to repair da

to the navigation locks and dams was estimated at $4 to $5 million dollars . Overall traffi

the Upper Mississippi decreased 30 to 35 percent for 1993, and daily losses to shippers 

estimated at $700,000 a day during lock closure .

To protect tows from currents and winds at high river stages, lock walls should be se

least 2 or 3 ft above the stage corresponding to the maximum navigable flow . On the Arka

River system, it was expected that the river would be navigable for flows up to the 10

recurrence interval flood . Velocities for larger floods were expected to be too high for safe 

8-9
efficient operation of tows. Therefore, the top of lock walls was set at the higher of 10 ft abov

pool level or 2 ft above the 10-yr recurrence interval flood . Access roads to the locks and da

also were set at the same elevation . The 10-yr recurrence interval flood is also the limit 

navigation on the Red River Waterway (140,000-145,000 cfs at Lock and Dam 2 and 120,00

cfs at the head of navigation at Shreveport) .

It is usually desirable to set the top of lock walls at as high an elevation as economic

of the project permit. Top elevations have been set such that the longest period of traffi

interruption during the largest flood of record would not exceed 10 to 15 days . Unless the t

of the walls is above flood stage, operating equipment on the walls must be removed each tim

the walls are likely to be overtopped, and cleanup is necessary after the water has subsided .

Lock Chamber Walls. Lock chamber walls are located between the upper and lower

gate bays and enclose the lock chamber . The top width of the land wall is generally 6 to 10 ft

and wall thickness at lower elevations are governed by size of conduits and openings fo

operating facilities and by stability requirements .

Design of the river wall is limited by its location adjacent to the spillway . Spillwa

releases flow along the river face of the river wall, and that wall may be designed with unifor

batter to provide smooth flow conditions . When the river bed is of erodible material, specia

protective measures (such as sheet piling or heavy stone protection) along the wall are require

to prevent scour from undermining the wall. The river wall is primarily subject to hydrostati

loading, as with the water surface in the lock chamber at upper pool level and lower pool leve

in the river below the dam, or with the lock chamber unwatered for repair or inspection an

lower pool level in the river below the dam .

In the case of two locks side by side, the intermediate wall has a constant top width, th

same as required for the gate bay walls . Both faces of the intermediate wall (which form th

sides of the two lock chambers) must have continuous straight surfaces for the tows to rub again

as they pass through the lock and to provide smooth vertical surfaces for mooring during lockage 

Thus, the upper portion of an intermediate wall cannot be narrowed for economy of construction 

Upper and Lower Gate-Bay Walls. These walls house the gate recesses, gat

anchorages, gate machinery, and sometimes culvert valves and culvert bulkheads . The top o

gate-bay walls must be sufficiently wide to :

a. House the operating mechanism .

b. Provide space for gate anchorages.

c. Enclose the valves.

d. Allow the gates to recess flush with the face of the wall for miter and sector gate

e. Provide sufficient concrete between the culverts and gate recesses for stability .

Culvert-intake Walls . These walls extend immediately beyond the upper gate bays an

provide space for the intake ports for the filling system . They are wide at the top to support 

a. Bulkhead-handling machinery when temporary closure structures are used .

8-10
C

b. Provide bulkhead recesses.

c. House floating-gage wells and other equipment .

Culvert-discharge Walls. These walls extend from the downstream end of the lower 

bay monoliths to the approach walls. They are usually lower than the lock chamber w

because they are below the lower gates and are subjected only to lower pool or high-water st

below the dam. They house the culvert-discharge manifold and diffuser system . When bulkh

are placed downstream from the discharge ports, the loads resisted by the culvert-discharge w

are similar to those on the lock walls during unwatered conditions .

Approach (Guard and Guide) Walls. Approach walls are extensions of the 

chamber walls at both ends of a lock and are required for all locks with barge traffic bec

tows have poor control and maneuverability when entering and leaving locks at low sp

Approach walls reduce hazards for tows entering and leaving the lock and reduce damage to 

tows and lock facilities. They speed up lockages by offering a wider target for tows heading 

a lock and provide temporary mooring space for tows with more barges than can be loc

through in a single lockage or for tows queued for passing through the lock. Optimum alignme

length, and design of approach walls should be investigated in a general model study .

At locks used by both large ships and shallow draft tows, long guide walls can b

obstruction to the ships which cannot enter a lock under their own power, but must be mo

into and out of the lock chamber by tugs or towing engines on lock walls (as at the Pa

Canal locks) .

One approach wall, the guide wall, is usually longer than the other, the guard wall. 

guide wall serves to guide tows into the lock, and tows can put out lines to check posts on 

wall to correct alignment for entering the lock. In the United States, many barges are 35 by 

ft and are locked through three abreast (105 ft total width) in a 110-ft wide lock chamber, lea

little clearance along the lock walls . Guide walls are usually straight-line extensions of the l

chamber walls; however, where guide walls serve as mooring areas, the mooring reach of 

should be flared away from the approach or offset from it .

The shorter guard wall is designed to improve lock entrance and exit conditions for t

and to prevent tows from drifting into areas with hazardous currents and turbulence .

Guide walls can be located on either side of the lock approach, depending on site 

current conditions, but are usually located along the landside . However, where cross curre

exist in the upper approach because of spillway or powerplant operation or in the lower appro

where a slow eddy often forms as the spillway or powerplant discharge widens out downstr

of the lock, it is desirable to locate the guide wall on the river side and the shorter guard 

on the land side.

The usable length of the guide wall is usually equal to the length of the lock cham

however, if the approach is well protected from wind and there are no adverse currents, a shor

length may be satisfactory . If conditions in the upper portion of the downstream approach 

hazardous due to turbulence or high velocities, the usuable length of the lower guide should 

8-11
measured from the point where velocities are less than 6 ft/sec or where excessive turbulence

ends (Davis, 1989) . Where banks are rock and tows cannot nose safely into the bank to queu

for passage through the lock, it may be desirable to lengthen the guide wall to provide moorin

space for more than one tow. In this case, the use of mooring piles should be considered, rathe

than longer walls, to reduce costs .

Approach walls (guard and guide walls) must be able to absorb impact and withstan

abrasion from moving tows ; however, local damage or failure of an approach wall when hit by

a tow is not a serious matter because the lock can continue in operation while repairs are made 

Various types of construction have been used for approach walls, each having advantages a

particular sites :

a. Guard walls are either solid or are provided with openings (ports), depending on flow

patterns and velocities at the specific site . For locks in reservoirs, the upstream approach wall

may be slotted to avoid flow concentration, cross-currents, and high velocities at the upstrea

end of the walls .

b. Gravity walls have been used for approach walls on rock, soil, and pile foundations,

but are expensive and rigid and require cofferdam protection during construction. In the Unite

States most locks on rivers have concrete gravity walls . If rock is excavated to provide projec

depth in the lock approach, the wall can be placed on top of sound rock and the vertical rock fac

below the wall lined with concrete .

c. Reinforced concrete continuous walls are sometimes used, but they are expensive 

Cofferdam protection is required during construction, and the thin sections are not as resistant to

impact as are walls of other types .

d. Floating concrete guide walls have been used in the upstream approach at some lock

in reservoirs where depths are large or foundation conditions are difficult .

e. Sheet pile construction (cantilevered or tied-back steel) can be used for landsid

approach walls where backfill extends to the top of the wall and where the approach channel i

earth . The wall is set back from the face of the lock walls an amount equal to the thickness o

timber fenders bolted to the piling . Construction cost is low, but such a wall can be severel

damaged by impact of tows . Steel sheet piling in double rows, connected by diaphragms or ti

rods and filled with earth can be used to form a continuous wall, and the top of the wall can be

capped with concrete .

f. Cellular steel sheet piling filled with sand can be capped with concrete and supported

by bearing piles . Reinforced concrete beams can be used between the cells to form a continuou

rubbing surface for tows.

g. Isolated guide or mooring facilities, such as concrete piers, sheet pile cells, and timber

pile clumps equipped with tie-up equipment, may be used at the ends of approach walls to absor

much of the impact from a tow out of control and to serve as mooring points for tows waiting

to lock through.

8.7 Lock Filling and Emptying Systems

The type of filling and emptying system used for • a particular lock depends on the lift

tonnage, capacity required, importance of the waterway, and construction costs . Lift is the mos

important factor . For low-lift locks (lifts less than 30 ft), a wall culvert-side port system can be

8-12
used, but an intermediate-lift lock requires a more elaborate design, such as bottom l

manifolds. For high-lift locks, it is usually desirable to use a bottom longitudinal man

system that splits the flow vertically in the main wall culvert by means of a horizontal diaph

and produces equal division of flow to four branch manifolds in the floor of each half of th

chamber.

Design of modern locks in the United States, including design of filling and emp

systems, has been based on model studies, primarily by the Corps of Engineers and the Tenn

Valley Authority.

To minimize lockage time, lock filling and emptying systems should fill the lock cha

in the shortest practicable time without disturbances that would endanger vessels or the lock i

particularly lock gates . Filling time is a function of lock lift. In the United States locks 

miter gates with lifts of 30 ft or less have filling times of 6 to 8 minutes, and locks with lif

30 to 60 ft fill in 8 minutes. For higher lift locks (60 to 100 ft), filling time is greater th

minutes.

There are several different basic schemes for lock filling and emptying system

numerous modifications of the basic designs for specific site conditions, as described later in 

section.

Hawser Stresses. Two types of disturbances in lock chambers related to lock filling 

emptying operations can be hazardous to tows being locked through :

a. Local turbulence generated by water entering or leaving the lock chamber and 

lower lock approach .

b. Surging in the lock chamber as it is filled or emptied .

Tows and vessels in lock chambers are moored to the lock walls by hawser li

Turbulence related to filling and emptying operations may damage small craft or indivi

barges in a lock, but surging is the more dangerous because it can cause an entire tow to 

loose from the hawsers in the lock chamber and damage the lock, lock gates, or the tow it

Stress in the hawsers is primarily a function of gross tonnage of the tow and slope of the w

surface in the lock .

In the hydraulic design of locks, both longitudinal and transverse hawser stresses 

measured in hydraulic models, but tows in a model are more - closely restrained than in 

prototype and there is more strain in the lines in the prototype than in the model . T

prototype stresses are normally less than measured in models, Figure 8 .14. Measurement

hawser stresses in models and prototypes have been compared for many years, and it has 

concluded that if prototype stresses measured in models do not exceed the following crite

lock will be safe for barge tows and other vessels :

a. For various numbers and sizes of barges in a lock chamber, hawser stress should 

exceed 5 tons and turbulence must not be hazardous for barges and small craft . The 5-ton v

8-13
is the result of consensus reached in the late 1960s by tow operators and owners, lock operators,

and laboratory and design engineers .

b. For single vessels up to 50,000 tons in a lock chamber, hawser stresses should not

exceed ten tons .

c. For single vessels larger than 50,000 tons, hawser stresses are allowed to exceed ten

tons since such vessels are restrained with more lines than tows or smaller vessels .

Summary data of permissible filling and emptying times for a 1200- by 110-ft lock to

keep hawser stress within 4-, 5-, 6-, and 7-ton limits (for lock lifts of 20, 30, and 40 ft) are

shown in Figures 8 .15 and 8 .16, respectively (Davis, 1989) .

Filling and Emptying Over, Between, or Around Lock Gates . A tainter gate on the

upper lock sill, Figure 8 .13, can be used to supplement lock filling by other systems . As the

tainter gate is lowered beneath the sill, water flows over the gate and into the lock chamber 

However, filling is normally accomplished by a special filling system consisting of :

a. Intake ports upstream of the gate sill (or in the gate sill) .

b. Wall culverts .

c. Laterals or ports in the lock chamber .

At St. Anthony Falls locks on the Upper Mississippi River, tainter gates at the locks serve

primarily as a supplementary spillway at flood stages and to pass ice and debris through the lock 

Sector gates, Figure 8 .13, are used as lock gates where reversal of head of significant

duration occurs, for example at a location affected by tidal action where the downstream water

surface is sometimes higher and sometimes lower than the upstream pool . As the sector gates

swing apart, water flows into or out of the lock through the opening between the gates, and the

lock chamber must be sufficiently long so that tows in the lock can be safely moored beyond the

region of local turbulent inflow. Some sector gates have been designed to also admit water

around the gates through the wall recesses .

Sector gates can be used with heads up-to about 20 ft, and reversal of head rarely occurs

at locks with normal lifts greater than 20 ft . Although sector gates are designed to operate at the

estimated maximum lift, such conditions are usually of short duration and relatively infrequent 

normal lifts are usually much less. Sector gates are used only when required, because other types

of gate are usually more economical to construct and other types of filling systems provide more

satisfactory operation .

Filling and Emptying by Valves in Gates or through Short Culverts. Early locks in

the eastern United States used valves located in the lock service gates or short culverts through

the river wall (each controlled by a separate valve) . However, modern designs use stub or loop

culvert systems around the service gate, Figure 8 .17a. In this design, short culverts in the service

8-1 4
C

gate monoliths carry water from the upper pool, around the gate, and discharge it into the l

chamber immediately downstream of the gate . Such systems are most economical where a l

is excavated in rock and walls are too thin to accommodate wall culverts . Systems of this t

are also used to empty a lock, Figure 8.32a.

Filling and Emptying through Wall Culverts and Ports or Laterals.

- Early conventional wall culvert and port systems . The following systems we

widely used for early locks on the Ohio, Tennessee, and Upper Mississippi Rivers and h

performed well for low lifts :

a. Wall intakes in the upper approach walls .

b. Longitudinal culverts in the lock walls .

c. Wall filling and emptying ports throughout the length of the lock chamber.

d. Wall discharge system downstream of the lower lock gates.

At some locks incremental valve openings have been used to reduce turbulence in the lo

chamber when filling and in the lower lock approach when emptying . Ten of the 11 loc

initially constructed by the Tennessee Valley Authority (TVA) with conventional systems ha

comparatively high lifts of 39 to 80 ft, and at some locks the valve operating time is lengthen

by holding the valve in a partly open position for various periods, depending on the size of t

being locked through . Turbulence and. transverse and longitudinal currents occur to varyi

degree at locks on the Upper Mississippi River constructed in the 1930s, and valve opening ti

are lengthened to improve navigation conditions.

- Modern systems . In an effort to lessen problems experienced with turbulence a

currents using the conventional culvert and port design, more complex systems were develop

to provide faster and safe filler and emptying operations . Modern systems for locks of low a

medium lift are generally of two types, and which system is used at a particular site is influenc

by foundation materials and traffic and is ultimately determined by economics .

a. Systems filling and emptying the lock chamber through ports along the base of 

lock walls (side wall port locks or side port locks), Figure 8 .18a . This is the most common ty

of lock on the inland waterway system in the United States and can be used for lifts from 5 

30 or 40 ft depending on lock chamber size, but generally is not suitable for higher lifts .

b. Systems filling and emptying the lock chamber through laterals and ports 

longitudinal culverts and ports recessed in the floor of the lock chamber, Figures 8.18b and 8 .

These systems take water from the upper pool through an intake manifold into wal

culverts that supply water to ports in the lock chamber . The lock is usually emptied through 

same system of ports and culverts and through a discharge manifold that discharges water eit

into the lower lock approach or riverward of the river wall of the lock .

Systems filling and emptying the lock through ports along the base of the lock wal

operate satisfactorily with moderate filling times, with the time required for filling dependent 

the lift and size of the lock chamber .

8-15
Filling and emptying systems recessed in the lock floor (laterals with . ports for low-

locks, Figure 8 .18b, or longitudinal culverts with ports for high-lift locks, Figure 8 .19) 

designed for fast filling times ; however, they require deeper excavation than is required for l

with ports along the lock walls. If the excavation is in rock, the additional cost may be hard 

justify. If traffic can be served safely by a lock with moderate filling time, such a design is 

cheapest and best solution . However, if projected traffic requires so many lockages that a fa

filling system or a second lock would be required, use of a more complex fast-filling design 

usually the cheapest and best solution .

Davis (1989) presented data relating lock volume to average filling inflow, Figure 8 

These curves can be used to obtain a preliminary estimate of lock filling filling time .

- Intake manifolds. Intake manifolds consist of a series of ports opening into a la

area that transitions downstream into a smaller rectangular cross section at the culvert cont

valve, Figure 8 .21. The use of multiple ports spreads the incoming flow over a larger area 

if a single large port were used, and this reduces the formation of vortices and entrainment of 

into the wall culverts.

Intake manifolds are usually located in approach walls, but in some cases are in the u

gate sill, as shown in Figure 8 .21, to pass drift and ice through the lock or to prov

supplementary discharge capacity. Intake manifolds are streamlined and are designed for f

in one direction only, and intake velocities are usually limited to about 8 to 10 ft/sec . All p

are the same size at the wall face, but have different throat dimensions . The height/width r

of ports at the wall face is usually in the order of from 2 :1 to 4:1 . The total port area at the 

face is about 2.5 to 3.5 times larger than the culvert cross-sectional area to reduce int

velocities and thus :

a. Reduce intake losses.

b. Minimize the formation of vortices that draw air into the system and create turbule

in the lock chamber when the air is discharged through the ports.

c. Minimize damage to trash racks on the intake ports .

The throat area of each port in the intake manifold is decreased successively i

downstream direction to obtain equal flow distribution through all ports . The head l

coefficient for the intake manifold is a function of the ratio of total port throat area (ZA P

culvert area (At ) and decreases as the ratio increases, Figure 8 .22. A value in the order of 

is desirable; values ranging from 1 .5 to 2.0 have been used successfully (Davis, 19

Comparison of model and prototype data shown on Figure 8 .22 indicates that further increas

the ratio of IANIA, beyond a value of about 2 has minimal effect on the head loss coefficie

Head loss through the intake manifold can range from 0.16 to 0.4 VV2 where V,, is cul

velocity .

Much shorter culvert intake walls are required if intake manifold ports can be located on b

faces of the walls (Siamese intakes), as for Barkley Lock, Figure 8 .17b .

8-1 6
C

C

The top of intake ports should be located well below the minimum upper pool level 

ensure positive pressure in the system . Davis (1989) suggests that minimum submergence bel

the minimum upper pool level be set equal to the velocity head at the throat of the mo

downstream intake port .

Trash racks are used on the face of intake ports, Figure 8 .23, to prevent debris and 

from being drawn into the system . When floating drift or ice is present, it is important t

intake velocities be limited to 8 to 10 ft/sec to avoid impact damage to the trash racks . Slots 

provided in the lock walls for the installation of bulkheads for unwatering the intake area f

inspection and repair.

Vortex action and entrainment of air at intake ports in gate sills can :

a. Reduce efficiency of the filling system .

b. Present hazards to operating personnel and small craft .

c. Produce dangerous conditions in the lock chamber when large blocks of air ar

expelled through the filling ports .

d. Result in damage to trash racks by debris caught in the vortex .

In general, vortex action has been found to be greater in the prototype than in mode

Model studies and prototype experience have shown that intakes in the upper gate sill are m

susceptible to vortex action than are intakes in the lock walls . At sill intakes there a

concentrations of high velocity in the approach and in the port entrances because the width 

flow is restricted to that of the lock sill ; the closed angle of miter gates affects uniformity of 

approach flow; and discontinuities at miter gate recesses can induce eddies leading to t

formation of vortices.

In model studies of intake manifolds located on the top of gate sills parallel to t

upstream gates, as at the St . Anthony Falls Lower Lock, Figure 8 .21c vortex action was reduc

or eliminated by:

a. Decreasing the distance between the intake manifold and upper lock gates .

b. Increasing the spacing between intake ports .

c . Increasing the intake port area at the sill face.

d. Increasing submergence of the intake .

To reduce vortex problems at both wall and sill intakes, Davis (1989) recommen

avoidance of the following conditions :

a. Unequal distribution of flow in the intake ports .

b. Openings in the guide or guard walls that induce diagonal currents .

c. Breaks in alignment of the approach walls .

8-17
Small vortices carry little or no air into the culverts and have essentially no effect on 

chamber turbulence ; however, large vortices can produce considerable turbulence . Vortices 

difficult to avoid in high-lift locks for shallow-draft traffic where the depth above the upper s

is shallow and the approach floor is at about the elevation of the upper sill .

There are no design criteria that will ensure that lock approaches will be free of vo

problems, but the problems will be minimized if flow conditions are symmetrical, velocities 

minimized, and maximum submergence is provided . Where a problem is anticipated, it sh

be investigated in a hydraulic model.

One of the more recent model studies to investigate potential vorticity at a lock intake 

a study at the Waterways Experiment Station of conditions at replacement locks at the 

Gallipolis Locks and Dam on the Ohio River (Davidson, 1987) . The two new locks (110- 

1200-ft and 110- by 600-ft) are located in a short excavated channel across the inside of a be

Two alternative intake designs were considered, Figure 8 .24. Intake designs were tested 

1 :25 scale model that reproduced 2500 ft of the Ohio River beginning 188 ft upstream of 

existing - lock guide wall. Model studies indicated vortex problems would occur with both int

schemes as originally designed . However, modifications developed in the model elimin

vortex formation for both designs .

Alternative I, Figure 8 .24a, involved filling the locks from the river through three l

culverts . In testing, it was observed that flow conditions were unsatisfactory and that 

following contributed to the formation of severe air-entraining vortices at the intake structu

a. Flow entering the intake was unsymmetrical .

b. Layout of the original approach walls caused water to swirl around the abutmen

c. There was insufficient submergence for the design .

Modifying the position of the approach wall to Position 2, Figure 8 .25a, decreased the seve

of the vortices ; however vorticies still occurred . Various other modification were studied . 

invert of the intake was lowered 15 ft, and flow entering the intake was made more symmetr

by relocating the approach walls and placing a dike upstream of the existing lock guide wa

A vortex suppressor plate 15 .4 ft thick was placed at the same elevation as the intake cond

roof and extended 17 ft upstream to the trash rack, Figure 8-25b . With these modifications, 

air entraining vortices were eliminated .

Alternative II, Figure 8 .24b, involved filling the locks from the river through a s

excavated channel supplying water to two intake manifolds in the guide wall and a third manif

in an intake tower . The original design of the intake tower had a sharp corner at the upst

front face, and a severe vortex developed at that point ; however, no vortices formed at 

manifolds in the guide wall . Several modifications of the intake tower were tested . A de

adding a straight vertical wall with a quarter of an ellipse immediately upstream of the in

tower, Figure 8 .25c, eliminated air-entraining vortices for this alternative .

- Control valves. Control valve in lock culverts are usually tainter gates in a "reve

position, that is, with the trunnions on the upstream side and skinplate and sill on the downst

8-18
C

side, as shown schematically in Figure 8 .26. With two exceptions, all locks built in the U

States since 1940 have reverse tainter control valves . Positioning the valves in this ma

prevents air entrainment in the low pressure area downstream of the valve, thus minimi

turbulence and high hawser stresses associated with release of air from the filling system into 

lock chamber. Air entrainment becomes a more severe problem as lock lift increases.

Lock filling criteria is based on not exceeding permissible hawser forces of 5 t

Hawser stress is related to turbulence which, in turn, is related to the depth of water (cush

in the lock chamber and over the filling ports . The cushion provided has a major impac

project costs, and the depth normally is not greater than needed for bottom clearance (in the o

of a few feet) because of cost . Depending on specific site conditions, such as depth to s

rock, it is sometimes economical to provide greater cushion .

Recommended prototype valve opening time to limit hawser forces to five tons for 

chambers of various sizes, based on model studies and reported by Murphy (1975), are s

in Figures 8.27 and 8 .28 .

- Wall culverts : Culverts in lock walls convey water from the intake manifold to 

filling and emptying system, and to the outlet system . Downstream from the intake manif

the culvert transitions to a rectangular or square section at the filling valve, with a culvert he

to width ratio of from about 1 .0 to 1 .15 . In wall culvert side-port systems, the culverts 

usually of uniform size from the filling valve to the emptying valve . Any culvert expans

should be gradual, about 1 on 10, to minimize head loss and turbulence .

The horizontal location of a culvert in the lock wall, the distance from the culvert to 

face of the lock wall, fixes the length of wall ports . This distance is sometimes determine

structural requirements . As a minimum, a port length of about 8 ft is desirable . In side-

systems, the elevation of wall culverts is established by submergence requirements for the p

and pressure conditions at the valves. In bottom filling systems, minimum depth in the 

chamber must also be considered . In high-lift locks with bottom longitudinal systems, valves 

placed low to control pressures and air intake, and the valves and wall culverts must be al

as low as the bottom manifold system .

To unwater valves for maintenance, bulkhead slots are usually placed in culv

upstream and downstream of the valve . To minimize cavitation damage, the downstream slo

located downstream of the vena contracta when the valve is 50 to 70 percent open ; locatin

slot a distance of three times the culvert height downstream will usually place it out of the a

most susceptible to cavitation . The upstream bulkhead slot is located at least two times 

culvert height upstream of the upstream edge of the valve shaft . For high-lift locks, steel 

culvert liners are used on all surfaces of the culvert downstream from the valve . Model t

indicate that the area most subject to cavitation damage is usually 2 .0 to 2.5 times the cu

height downstream from the bottom seal line of the reverse tainter valve, and the liner ext

downstream past this area .

- Wall-port systems. Wall ports to fill and empty a lock chamber are designed for 

in both directions. They are streamlined, with rounded entrances and exits, and are flared to 

8-19
lock face to reduce exit velocities when filling . The design shown in Figure 8 .29 is consid

the best of many designs tested . The ports occupy 50 to 60 percent of the lock length and 

located in the center portion of the lock chamber to minimize surging during filling. Ports in 

wall are staggered with respect to ports in the opposite wall so that the jets from one wall do 

collide with jets from the opposite wall, but pass each other and there is good distributio

energy with little turbulence .

As the filling jet exits the port, it flares upward at about 7 degrees ; thus flaring abou

ft when it reaches the opposite wall of a 110-ft lock. If wall ports are staggered and set on 2

centers in a 110-ft lock (at 20-ft spacing in an 84-ft lock), this expansion takes place between 

issuing on the opposite wall, minimizing turbulence . Culverts and valves should be sized to c

the jets to the far side of the lock chamber, but port outflow should not be sufficient to cau

welling up of water on the far side of the lock . . Locks narrower than 110 feet have side po

set on lesser spacing and lesser discharge from the wall ports to avoid upwelling on the far s

Wall ports should be of sufficient size so that the jets do not completely diffuse be

reaching the opposite wall or boils will occur at the surface, thus increasing hawser stresses . 

higher lock lifts, the ports may be directed down toward the base of the opposite wall to red

turbulence. Model studies for Arkansas River locks indicated that triangular recesses, Fig

8.30, in front of the upstream one-third of the ports would reduce upstream longitudinal ha

stresses during filling .

For shallow-draft locks, the bottom of wall ports should be set at the elevation of 

bottom of the wall culvert and at, or slightly below, the level of the lock floor .

The total port throat area in one wall should be about 95 percent of the wall culvert 

A smaller ratio would increase filling time, and a larger ratio would result in less favor

hydraulic conditions in the lock chamber. Port face area varies with lock chamber size

recommended by Davis (1989) :

a. 10 to 11 sq ft for a 1200- by 110-ft lock .

b. 9 to 10 sq ft for a 600- by 110-ft lock .

c. 6 to 7 sq ft for a 600- by 84-ft lock.

- TVA multiport system. In 1959 the TVA used a somewhat different filling 

emptying system in design of three new locks with lifts of from 42 to 60 ft on relative high r

foundations. The multiport system, Figure 8 .31, required less excavation and was 

economical than the culvert-lateral-port system .

- Lock chamber lateral diffusers . A lock chamber lateral diffuser is a filling 

emptying system of small culverts (laterals) across the lock chamber with ports in the late

The laterals are recessed in a trench in the lock floor so that the jets mix and dissipate mos

the energy below the main body of water and tows in the lock chamber, minimizing ha

stresses. A typical installation is shown in Figure 8 .18b . They are more expensive than wall 

systems, but may be economically justified at some locks serving heavy traffic on the basi

reduction in lock filling and emptying times .

8-20
C

J

C

Lock chamber lateral diffusers are similar to discharge diffusers, but differ in that 

are designed for flow in both directions, that is for both filling and emptying operations . 

are located in the middle third of the chamber for a 600-ft lock, as for the Greenup auxiliary 

Figure 8.18b. For a long lock, for example the 1200-ft Greenup main lock, Figure 8 .18b

diffusers are split into two systems to keep hawser forces within acceptable limits and one g

of laterals is located approximately the middle third of the upstream half of the chamber and 

other in the middle third of the downstream half of the chamber .

- Lock emptying systems . Lock emptying systems are designed to discharge 

distribute outflow from lock emptying so as not to cause turbulence or currents that w

endanger craft in the lower lock approach. Outlet systems usually discharge either to the l

lock approach (between the lower guard and guide walls) through wall port manifolds or later

or on the river side of the lock, Figure 8 .32. The emptying culvert is widened downstrea

the emptying valve to reduce exit velocities and head loss, and the discharge system is desi

for flow in one direction only.

Where locks empty into the lower approach, a system of laterals across the lock usua

is used to minimize turbulence. The single culvert discharge laterals for St . Anthony Falls L

Lock, Mississippi River, is shown in Figure 8 .33. The flow area (cross section) of the late

is decreased in the downstream direction (across the lock) at successive ports for uni

discharge through the ports . The outside walls of the laterals are parallel, and ports in adja

laterals are staggered so that jets issuing from the ports are offset and do not collide and 

diffuse laterally before reaching the opposite wall.

The emptying system for the Snell Lock, St. Lawrence Seaway, Figure 8 .32b, 

discharge culverts in both walls and extensions on all ports to direct the jets perpendicul

across the trenches and produce a better flow distribution in the lower approach.

Wall discharge manifolds have been designed to empty completely or partially into 

lower lock approach, as for the McArthur Lock, St. Mary's River, Figure 8 .32a, and the 

Cumberland Main Lock, Ohio River, Figure 8 .34. The New Cumberland emptying system 

designed to divert two-thirds of the discharge outside the lock approach . Ports discharging 

the lock approach are staggered to minimize interference by opposing jets .

Davis (1989) reports that turbulence experienced at these three prototype locks is great

for the St. Anthony Falls Lower Lock, less for the New Cumberland Lock, and least for Sn

Lock. However, cushion depths over the outlets varies significantly for these locks, being 2

ft at St. Anthony Falls, 24 ft at New Cumberland, and 48 ft at Snell .

Discharge into the lower lock approach during emptying can create currents that adver

affect upbound tows . When the emptying manifold is placed riverward of the lock, the empt

operation generally has no effect on tows approaching the lock . The emptying system 

Greenup Locks, Ohio River, Figure 8 .32c, is typical of systems that divert the entire outf

riverward of the lock. Stilling basins are usually included in such outlets to reduce turbule

With such designs, the lower lock entrance is completely free of disturbances during empty

operation and the entire length of the guide wall can be used for mooring tows . However, out

8-21
such as for Greenup Auxiliary Lock may cause a problem with miter gate operation at modera

flows when the stage in the lock approach is lower than at the outlet (and in the lock chambe

causing a head differential at the gates . Miter gates normally require equal water levels on bo

side of the gates for opening .

Another outlet design, used for some of the Arkansas River locks, includes a system o

baffles, Figure 8.35. Such designs are suitable for low-lift locks at some locations.

A recent example of an emptying system discharging on the riverward side of the lo

is the Olmsted project now (1995) under construction on the Ohio River 16.6 miles upstre

from the junction of the Ohio and Mississippi Rivers . The Olmsted project, with two 110- 

1200-ft locks and a design lift of 21 feet, will replace two existing locks Locks and Dams 52 an

53, having lower lifts . Tailwater at the site is not affected by a downstream navigation structur

Open-river conditions prevail downstream, and tailwater is influenced by Mississippi River stage

The emptying systems are unique in that discharge culverts from the land wall, the middle wal

and the river wall all empty into a common outlet structure in the river, and culverts from t

land wall and middle wall pass under the floor of the river lock (Stockstill, 1992) . The outlet 

located 25 ft riverward of the river lock in the vicinity of the lower gate monolith . The 14- 

18-ft culverts drop 21 ft vertically over a 76-ft length in the lock walls and then turn 90• to t

outlet, Figure 8 .36.

Bottom Longitudinal Filling and Emptyji g_Systems. For higher-lift locks, the bott

longitudinal filling and emptying system, with longitudinal culverts with ports recessed in t

floor of the lock chamber, has become widely used, as for Lower Granite Lock on the Sna

River, with a 32-ft lift, Figure 8 .19. These systems are complex in design, but model studi

indicate they are superior to other systems for medium- and high-lift locks because of l

turbulence in the lock chamber and low hawser stresses, with less chance of damage to tows o

to the lock itself. In the bottom longitudinal system, flow in the wall culverts passes into 

"crossover" culvert across the lock at the center of the lock chamber, as for Dardanelle Lock 

the Arkansas River, with a 54-ft lift, Figure 8 .37. A splitter wall in the crossover culve

distributes flow equally to two longitudinal floor culverts with ports, one in the upstream half 

the lock chamber and the other in the downstream half of the lock chamber.

The bottom longitudinal filling and emptying system for Dardanelle Lock on the Arkansa

River, a "side-by-side" system, Figure 8 .37, is representative of such systems designed in t

1960s. The design was later refined and modified, particularly for locks of higher lift and 1200-

length. Murphy (1980) recommended that the side-by-side design not be used for lifts in exces

of 60 ft based on experience with the Bankhead Lock on the Black Warrior River with a 69-

lift, Figure 8 .38.

Model tests indicated that the side-by-side system designed for Dardanelle Lock could fi

the lock in 8 .4 minutes with a maximum longitudinal hawser stress of about 5 .2 tons with norm

2-minute valve operation . Model studies also indicated that baffles along the walls and betwe

the longitudinal culverts, Figure 8 .37b, would reduce bottom water movement toward the en

of the the lock chamber, reducing individual boils and turbulence so that conditions would b

satisfactory in the lock chamber with normal operation .

8-22
6

c_

Examples of the "over-and-under" bottom longitudinal filling and emptying system 

shown in Figures 8 .38 and 8 .39. At both locks flow from the crossover culvert is directed 

combining culverts upstream and downstream of the crossover culvert . At Lower Granite 

on the Snake River (lift 105 ft), there are four floor culverts in each half of the lock chamb

while Bay Springs Lock on the Tennessee-Tombigbee Waterway (lift 84 ft) has two culverts 

each half, Figure 8 .39. The Bay Springs system under construction (looking upstream) is sh

in Figure 8 .40. The floor culverts are 14 ft wide and 9 ft high, each with 12 pair of ports 

ft wide and 3 .5 ft high, spaced 15 ft on centers, with a port/culvert area ratio of 1 .0 . With 

design and a 1-minute valve operating time, the lock filled in the model in 9.9 minutes 

longitudinal hawser stress of about 7 tons and transverse hawser stress of about 6 .5 tons. 

lock emptied in about 11 .7 minutes .

Culvert area ratios . Murphy (1980) suggested that a relatively constant cro

sectional area be maintained from the wall culverts through the crossover culverts and 

combining culvert . He further suggested that initial studies of filling time and cost be primar

concerned with culvert size in this area and that filling valve size be determined later .

Longitudinal floor distribution culverts . Murphy (1980) noted that in the 670

Bankhead and Bay Springs locks two distribution culverts in each half of the lock chamber 

adequate, but that general tests of a 1200-ft lock indicated four were required in each half . 

suggested that the number needed probably depends on lift and culvert size as well as on 

length/width ratio of the lock chamber.

Port manifolds. Murphy (1980) recommended that :

a. Port manifolds extend over at least 50 percent of the length of the chamber .

b. If two culverts are used in each half, manifolds be centered on the one- and th

quarter points of the chamber, with each manifold extending over at least 25 percent of the to

length of lock .

c. If four culverts are used in each half, manifolds be centered on the one-, thre

five-, and seven-eights points of the chamber, with each manifold extending over at least 

percent of the total lock chamber length .

Ports. Ports tested in model studies have ranged in size from 4 .2 to 6.28 sq ft, 

Murphy (1980) favors a port similar to that used at Bay Springs (3 .5 ft high, 1 .5 ft wide, 

sq ft total area) because those ports gave good distribution of turbulence in the lock chamber 

are large enough to allow access for inspection and maintenance . He noted that, while 

sidewall port system the total cross-sectional area of ports should be about 95 percent of 

culvert area, with the relatively short distribution culverts in this system a port-to-distribut

culvert area ratio of 1 .0 is preferable and that all available space should be used for the p

manifold . He suggested there should be a relationship between trench size and port size, 

lift also a factor, so that a large portion of the kinetic energy of jets from the ports is dissipa

in turbulence in the trenches along the distribution culverts . Baffles are needed on the wall

the trenches and between the distribution culverts to prevent upwelling of jets from the port

8-23
Operation. Due to differences in friction factors between model and prototype

prototype locks with bottom longitudinal culvert filling and emptying systems can be expect

to fill about 16 percent faster than indicated by a 1 :25-scale model (Murphy, 1980) .

8.8 Closure Facilities for Locks.

All Corps of Engineers locks have facilities that can be set in place in still water f

maintenance of the lock chamber and lock gates . However, few locks have the capability 

make closures in flowing water under emergency conditions.

Navigation locks are vulnerable to accidents that result in damage and failure of lock gat

so that the pool is drained down through the lock to the top of the upper gate sill . In the Uni

States, accidents with tows ramming miter gates occur from time to time . In a typical case, a 

entering a lock rams and knocks out the closed gates at the far end of the lock chamber bef

gates behind the tow can be closed . (In one instance,, a vessel out of control knocked out t

gates at both ends of a lock.)

When miter gates are damaged and cannot be closed, uncontrolled flow through the lo

chamber can result in significant losses . The extent of such losses depends principally 

development upsteam and downstream of the lock . In a highly developed area, such as along t

middle reach of the Ohio River, monetary losses and other hazards can result from :

a. Loss of the upstream pool.

b. Flood damage downstream from the lock.

c. Losses to shipping using both pools, particularly in the upstream pool .

Loss of the upstream pool storage can result in loss of municipal and domestic wat

supply if the water surface falls below the elevation of the water supply intakes, loss of condens

water for power plants, and losses and damage to tows and vessels that are beached on t

channel bottom . Unrestricted flow through a lock may cause a sudden rise in downstream po

level, causing small craft and barges to break their moorings and drift uncontrolled into . 

channel, sometimes lodging against the spillway of the next dam downstream . A sudden a

unexpected rapid increase in river stage can result in greater flood damage to equipment a

installations than would occur with a normal slower river rise .

- Maintenance closures . Maintenance and operation costs should be considered 

selecting the type of closure facilities for a particular lock. At a high-lift lock with a h

upstream gate sill, a submergible vertical-lift gate or tainter gate at the downstream edge of 

upper gate sill is generally the best solution . However, use of use of such gates at a low-lift l

could result in high maintenance costs because of sediment accumulation on the gate and the ne

for periodic costly sediment removal. Emergency closure structures can also be used for routi

maintenance work that requires dewatering .

Maintenance closure facilities at most Arkansas River locks consist of a center post t

is set in a recess in the lock sill with 55-ft long stoplogs on both sides extending over to the l

walls.

8-24
C

ft above the 2 percent duration flow on the Ohio River), and this may involve added costs 

raising the spillway piers.

Stop logs placed with a derrick or crane have several advantages in addition to 

requiring an overhead structure, including : reliability; no permanently submerged structure

maintain; and little maintenance required for the stop logs, hoists, and derrick or cr

Difficulties are that installing stop logs requires considerable time and space is needed for st

of the stop logs near the upstream end of the lock.

Stops logs cannot be placed individually in flowing water ; water flowing over 

under an individual stop log produces vortex trails that cause eratic movement, and the stop 

jams in the wall recesses. Accordingly, the first stop log is placed in the recesses above 

flowing water and held there temporarily ; additional stop logs are added one by one, and 

entire unit is lowered into the water incrementally, as each stop log is added.

c. Sector gates can be closed in flowing water in a few minutes and require no spe

equipment, personnel, or mobilization . However, they are large structures and req

considerable space, have a very high first cost, require maintenance, and may have a prob

with differential settlement if the lock is wide .

d. Overhead vertical lift gates require a high structure across the lock and are unsuit

where high clearance is required for navigation .

Emergency closure sills are discussed earlier in this section . Closure facilities, inclu

all appurtenant equipment (cranes, hoists, trucks, and auxiliary power source), should be read

available and should be inspected periodically to ensure they are operable . Such facilities sh

be designed to close off uncontrolled flow as quickly as possible, depending on site spec

conditions. At some locations (e .g . the Ohio River) uncontrolled flow should be stopped in 

3 hours. The time factor may not be as critical at other, less-developed, locations .

8-25
Upper guard wall

---Dam

(a) Layout for a single lock

(b) Layout for adjacent locks

(c) Layout for twin locks

Figure 8 .1 Typical lock layouts.

8-26

Main lock

Lower guard wall
Gated Dam . Section D-0

General Plan

Scale (ft)

Figure 8.2 Typical low-lift navigation lock and dam (Ables and Boyd, 1966) .
Figure 8 .3 . Melvin Price Locks and Dam, Mississippi River

(Replacement for Lock and Dam 26) .

8- 28
0

i

.t

C

Figure 8.4 . Lock in deep part of bend.

3

l

(a) Stage I of two-stage cofferdam

a

(b) Stage I of two-stage cofferdam

(c) Stage I of two-stage cofferdam

(contractor's proposal)

(d) Stage II of two-stage cofferdam

Figure 8 .5 . Cofferdams for stage construction .

8-29

(e) Stage 11 of three-stage cofferdam

a . Cofferdams for stage construction,

Lock and Dam 3, Arkansas River

(Franco and McKellar, 1968.)

I

N A V

MISSISSIPPI

FIRST STAGE

COFFERDAM

FIRST STAGE DAM

EXISTING FIRST

STAGE COFFERDAM

I G'OT,;-*'O ;N CHANNEL

OVERFLOW DIKE

A.,

THIRD STAGE

COFFERDAM

AW

SECOND STAGE

COFFERDAM

134P.

K

EXISTING ILLINOIS

PROTECTION kL179

Figure 8 .6 . Three-stage cofferdam scheme,

Replacement for Lock and Dam 26, Mississippi River .

8-31
RIGHT

SANK -j

sIP- - IM r&~Mwwwwn - 11 .

I

C OF LOCK

==CMILLS

0 STAGE CELLS

la S7AGII=CgLLS

SrAG9=CILLS

CANOE

.86OPI .P. MINSp 0. AGE STAUGE I

CELLS REMAIN FOR

IN

STAGE

STAGE It

C,AND PIIIM

a

IN STAGE

!ATI16MMOMPF'VORNSTAGE=

,

C

:- COMPUTION43A-LOCK CELLS

Iff Tweaft CRIS CONNECTION TO

FIRMANANT STRUCMRK

PROFILE

	 I S7AGEZZr	I	(STAGES

.Ge-71 rOP OP UPSTREAM CELLS	STAGER	3F UPSTREAMELLSELJ79

MP OF i

EL a7J

TOP OF UPSTREAM CELLS 1U

UPSTREAM CELLS EL 120

M

8-32

-LEFT BANK

Figure 8.7 . Four-stage diversion plan, Dardanelle Lock and Dam,

Arkansas River.

NOTE

To OF ALL DOWNSTREAM1~4

.N

1 LLS

IS AT KL218

LEGEND

Ile
C

C

40

0

. . . . . . . . . . . . . .

Ow

1

s

E

IK

S

h

50'

OF DAM AXIS

o ho

'NORMAL UPPER

POOL EL 58

CL•e EL

v

Figure 8.8 . Red River Locks and Dams constructed in dry in cutoffs

on rectified river alignment.

8-33
.- .-MOMO.w .-

Figure 8.9. Lock walls, gates, and sills .

Figure 8.10 . Bay Springs Lock chamber during construction,

looking at upstream gate sill, Tennessee-Tombigbee Waterway .

(U.S. Army, Corps of Engineers, Nashville District.)

8-34
C

c

r•r

I

Ws.

(a) Lower lock gate partially open (view from inside lock chamber)

r

-3' fW f

(b) Lower gate fully open and recessed in lock wall

Figure 8.11 . Lock miter gates, Lower St . Anthony Falls Lock and Dam,

Upper Mississippi River.

8-35
Top of lock wall, el . 755

Upper pool, el . 750

Skinplate

Sill crest, el . 736 .3

(a) Detail (after Nelson and Johnson, 1964)

Figure 8.12. Submergible tainter gate (56 ft . long),

Lower St. Anthony Falls Lock, Upper Mississippi River .

8-36
C

Sector gates

Vf

ATA

V, ( b) Sector gates, O'Brien Lock,

Calumet-Sag Project, Illinois

(after Nelson and Johnson, 1964)

(a) Plan

Figure 8.13. Sector gates .

8-37

Lock

wall

A

VF
16

14

0

0

2

a

6

0- ,,- BARKLEY

LITTLE GOOSE

N.JACKSON

LOWER GRANITE

BANKHEAD

a-- LOWER ST ANTHONY FALLS

ARKANSAS. TERRY NO. 6

a10 12

PROTOTYPE P1WNG TIME. r MIN

1

14

16

Figure 8.14. Prototype vs model filling time .

8-38
G

C

C

Z

mim III t

as

~W,=W

km am&I zi OU.

M- ONI a. =11

=I

RL.

M~

mmmmmm

r

O-FT AD

35

30

25

40

35

30

25

20

7

la12

FILLING TIME, MIN

Figure 8.15 . Permissible filling time to keep hawser stresses

within 4-, 5-, 6-, and 7-ton limits, 110- by 1200-ft lock.

aa

EMOtyINa TI3E,M,M

Figure 8.16. Permissible emptying times to keep hawser stresses

within 4-, 5-, 6-, and 7-ton limits, 110- by_1200-ft lock.

8-39

Hawser stresses were 

on an f 8-barge tow (33

displacement) positione

upstream miter gate pi

Submergence is the dif

elevation between lowe

lock chr floor.

Culvert= was 268 sq 

20-FT HEAD JO-FT HEAD . o‚c r HEAD

I

t

.I

I

I

I I ~t rr I

I

2 IU

.v

a

Iy

~~ 2 (

In
Intake

manifold

Normal upper

Filing valve

pool . ei . 200.0

T- -

Intake

manifold

Normal upper

pool, el . 515.0

a. Stub culvert system with diffuser.

(Nelson and Johnson, 1964) .

Figure 8 .17. Typical lock Filling systems .

Stub culvert

chamber

Wall culvert

,K

Filing and emptying ports

Outlet

Emptying

- valve

I

b. Greenup Locks, Ohio River (lift 32 ft).

Figure 8 .18. Typical low-lift lock filling and emptying systems .

(Nelson and Johnson, 1964).

8-40

Aser

t=,~

Emptying valve

Discharge manifold

a. Snell Lock, St. Lawrence Seaway (lift 49 ft) .

Land wall

b. Siamese system, Barkley L

(U.S . Army, Corps of Engineer

ssa=M

Normal lower

pool, el . 151 .0

~A- I

Lj Lj

Intake ports
CD

Figure 8 .19 . Lower Granite Lock, Snake River. (Murphy, 1980).

7

6

2

ARKANSAS'NOTE: JONES BLUFF

DOES NOT HAVE

SIDEPORT SYSTEM

JONESVILLE

II

4

T,

8.20 . Lock volume vs average discharge (model filling time) .

(Davis, 1989) .

8-41

610

AVERAGE DISCHARGE INTO LOCK A, x H . 1 .000 CFS

I	

12
Mil

40117,1111

83 .45 ft 1

36.82 ft

Elevation

a. Bay Springs Lock, Tennessee-Tombigbee Waterway .

.s

vA

0 5.5

ILVAIM

b. Ice Harbor Lock, Snake River.

15 ft

I

FIT

. ~ , .

El. 711 .8

~-

Elevation

c. St. Anthony Falls Lower Lock, Upper Mississippi River .

Figure 8.21 . Typical intake manifolds (U .S. Army, Corps of Engineers) .

8-42

Plan

Top lock wall, el . 430

Normal upper pool, el . 414 --y	

Intake porlts

El . 366 ice--Si'h i

l . 393

00000001.

l El . 352

IIL
a

w

0=

a

w

a

1 .5

-0

Ix

0

-o

1 .0	1	I	I

00 .1 0 .2 0 .3

LOSS COEFFICIENT, k,

Figure 8.22. Intake head loss coefficient (Davis, 1989) .

8-43

Oh2 - HEAD LOSS

h L (DTO02 - k,

v/2g

c

E AP - THROAT AREA OF INTAKE

Sectional plan .

3 .0
Figure 8.23. Intake ports with trash racks in place during construction, 

Dardanelle Lock, Arkansas River.

8-44
0

Mft~

•.sa*I*-----

41b

f4wWwav ~rart --

ONTO

a. Alternative I .

b . Alternative II .

Figure 8.24. Alternative filling schemes, Gallipolis Locks and Dam, Ohio River

(Davidson, 1987) .

8-45
a . ,Intake approach, Alternative I .

0

Oh/0 4

q'fq

1V ON 5N

TYPE D ESIONEL 505 .0

APPROA H WALL

EL 501.0

PORTED

INTAKES

IV ON 3"

rSEE DETAIL 'A'

=1

8-46

SECTION B-B

r

c. Alternative II, Intake canal and manifold .

Figure 8.25. Intakes for alternative filling schemes,

Gallipolis Locks and Dam, Ohio River

(Davidson, 1987) .

78

PLAN

b. Intake structure, Alternative I .

I - I~i -1 I IfliLillil ELEVATION

PLAN

DETAIL "A'
C

3

2

0

10

V,,c Mean Velocity in Vena Contracts

Figure 8.26. Culvert control valve

("reverse" tainter gate).

Vc = Mean Velocity in Culvert at Valve

i

i

I

S - Vc

4

I

670 ft x 110 ft lock655 ft x 84 ft lock

o

i

i

i

1270 ft x 110 ft lock

i

i

Model data

0 670 ft x

a 1270 ft x

0

5

0

67 8 9 10

Permissible filling time (min)

Figure 8.28 . Permissible filling times (model)

(Murphy, 1975).

8-47

110 ft lock

110 ft lock

1

2 3 4

5 6 7 8 9

Valve time (min)

Figure 8 .27 . Recommended prototype valve opening times for filling

(Murphy, 1975).

50

40'

30

-' 20

10

0

Lock size

670 ft x 110 ft

A --o 655 ft x 84 ft

a--a 1270 ft x 110 ft

0-0

11

.

12
o .

2 .54 ft -	20 -1 1

Culvert

(b) Section A-A

y

(a) Plan

v 8 ft min.

2ftR 1 ft R

e

Figure 8 .29. Ports for 110-ft-wide lock.

(Murphy, 1975) .

d . ‚

Lock chamber'

8-48

t

qmft

(b) Section A-A

Figure 8.30. Port deflector for 110-ft-wide l

-(Murphy, 1975).

Figure 8 .31 . NA multiport system (Elder et al ., 1964).
C

Lock chamber

Filling and

emptying laterals

.

Wall culvert

Emptying valve

AIIIIIIIIIII

111111 _ice

Lock chamber

.6

b. Snell Lock, St. Lawrence Seaway

(Nelson and Johnson, 1964) .

Wall culvert

Emptying valve

LIIIIHUIIIIUI~-/-

IIIIIIIIIUIIB

River discharge outlet

c. Greenup Lock, Ohio River

(Nelson and Johnson, 1964) .

Figure 8 .32. Typical lock emptying systems .

8-49

Lower lock approach

Emptying laterals

Lower lock approach'
Figure 8 .33 . Discharge diffuser, St . Anthony Falls Lower Lock, Mississippi River .

(U.S. Army, Corps of Engineers, 1956) .

Y*DoLL WALL

RIVL* WALL

rLow

W

w.

T' . !a . t . . L--ipwbw"

Figure 8 .34 . Discharge manifolds,

New Cumberland Lock, Ohio River (Davis, 1989) .

8- 50
a

CD

L

-J

TOP OP WALL EL /74 0

770'

I

--~-t {.- .-	 ~- /S

70i W EL /290 1 I	r~ ne.o

b. Plan

a. Section

b. Section B-B

Figure 8 .35. Discharge manifold with baffles, Arkansas River

(Davis, 1989) .

8-51

nnnn

ILJ

	 es.o'

1421'	5.79'	42.0'	JS 0'	47 O'

i

. .~ ./- I

	

4Js

13

_,

	 .O'R 7J'A

ti

1 I I II I I

I.

1 I

4

	

I

1	1

S 8AFFLE5.9.S'OC' . JO'MICM

NO'

1

1

lot

IM

I

f

Fe
EL 235

20'185 20',8'I 20' .8" 20'

It I I I I t

	

I I I I I I 25'

1	I	I	i	,	1

JA'1 JA- 1 14 - 114 - 1 JA- 1 JA- 1 JA'

,I I I I

r- FROM RIVER WALL CULVERT

FROM MIDDLE WALL

C(RIVERLOCK)	

I il~ II II II

I 1 I t I I

,

i

FROM MIDDLE WALL (LAND LOCK) CULVERT --11

FROM LAND WALL CULVERT -~

c . Culvert and bucket detail .

145.5'

EL 235

b. Vertical transition .

EL 268

	 :'_268

EL253

EL235

140 .08'

OHIO RIVER

FLOW

2.7V ON 1H

LAND LOCK CHAMBER

Figure 8.36 . Outlet system, Olmsted Locks, Ohio River

(Stockstill, 1992) .

8-52

II

II I

	

2V ON 3H

~-I 27V ON IN

235

1

	

II I II

III i t 1 1 - rOUTLET CULVERT

i I I

---+----~	1 1" Xi 18' CULVERT

,

I I i 1

I I I I

.o4 NI VERTICAL

yi- eI TRANS1Ti0N .pin

I1 I	eo

I TI o

"IIn

I M

140.08'

>IRIVER LOCK CHAMBER i

I

NIQ pl i i

Ip

. VERTICAL

	

I I

TRANSITION 	I

I

	

	

n h	114,E RL_

f	,4x118CULVERT _r 8

19'

--- -	-----------I 14' Xi 18' CuIVERT ~i •

VERTICAL

I1I

^~TRANSITION DI

n 1 r11

	 a''s=x

--------

I 1 14' . 18' CULVERT	

-	 I-'

1-m1 VERTICAL I

pI

hiIQ

a1 TRANSITION

m CI I

i

I C NI

u In

6nlnl

a. Plan .

f
01

v

Filling valve

Wall culvert

11 c

II

)t

324.5 ft

Longitudinal floor culvert ~_

Upstream miter gates

b. Culverts, ports, and baffles .

670 ft

345.5 ft

Emptying valve

I	 Il D4 II	

Splitter wall

	 Ports

Downstream miter gates

0 .

N

77

a	

a. Plan.

Figure 8.37. Bottom longitudinal "side-by-side" filling and emptying system,

Dardanelle Lock, Arkansas River. (Ables and Boyd, 1969 .)

8-53

a
Figure 8 .38. Bottom longitudinal "over-and-under" filling and emptying system,

Bankhead Lock, 69-ft lift, Black Warrior River, Alabama

(Murphy, 1980).
E-7-1-01

-I

Figure 8 .39 . Bottom longitudinal "over-and-under" filling and emptying syste

Bay Springs Lock, 84-ft lift,

Tennessee-Tombigbee Waterway. (Ables, 1978) .

Figure 8 .40 . Bay Springs Lock under construction, Tennessee-Tombigbee Wate

(U .S. Army, Corps of Engineers, Nashville District) .

8-55
c

9.NAVIGATION HAZARDS AT LOCKS

Flow conditions in lock approaches and lock chambers and gate sill elevation

present hazards to navigation traffic . Typical problems at specific projects related to curren

shoaling in lock approaches, surges in lock chambers and approaches related to fillin

emptying operations, and tow squat are described in this section .

It should be noted that velocities and currents on some canalized rivers become too 

for safe and efficient tow operation during floods. Navigation ceases at about the 

recurrence interval flood on the Arkansas, Red, and Upper Mississippi Rivers . On the Arka

this is 250,000 cfs at Van Buren, 335,000 at Dardanelle, 350,000 at Little Rock and downst

On the Red River, this is 125,000 cfs at Shreveport and 145,000 from Alexandria downst

when mean channel velocity is in the order of 7 ft per sec and maximum velocities exce

ft per sec . Lock and Dam 26 on the Mississippi River goes out of service at about 720,000 

Navigation locks are usually located in relatively straight reaches and in or near ch

crossings in order to obtain adequate site distances in the upstream and downstream approa

The best sites are cross sections that are somewhat wider than the average stream cross se

because they provide sufficient width to compensate for obstruction of flow by the loc

spillway piers . Cross currents resulting from spillway operation (and power plant dischar

power is included in the project) and currents due to the natural channel configuratio

important considerations in site selection.

Constriction of the natural channel by a lock usually results in cross currents i

upstream lock approach as flood flows move across the lock entance toward the spillway . 

currents tend to develop near the upper end of the guard wall, Figure 9 .1 The intensity of 

currents can be reduced by constructing ports in the guard wall, to pass flow intercepted b

guard wall, and by reducing velocities in the approach channel by using dikes to redistribute 

across the channel. Also, turbulence and vortices may occur in the immediate vicinity o

structure due to operation of the filling system .

In the downstream lock approach, undesirable and dangerous currents derive from 

principal sources :

a. Spillway and power plant discharges .

b. Expansion eddies immediately downstream of the lock.

c. Currents from the lock emptying system.

Currents and velocities from a lock emptying system in the lower lock approach ca

dangerous to tows approaching the lock, especially at medium- to high-lift locks . At such 

it may be desirable to locate the discharge manifold outside the lower lock approach, 

Greenup Lock, Figure 8 .18b, and at Olmsted, discussed in Section 9.4.

Where releases from the dam expand downstream of a lock, sediment tends to 

toward and into the lower lock approach, and the resulting deposition can be a signif

problem.

9-1
9.1Dardanelle Lock and Dam, Arkansas River

Model data for two alternative layouts of the power plant at Dardanelle Lock and Da

(lift 54 ft) illustrate the occurrence of cross currents in the upper lock approach with a ported

upper guard, wall, Figure 9 .1 . Ports in the upper guard wall reduce cross currents by permitting

the flow intercepted by the lock to pass through the wall to the spillway . The effectiveness o

ports in reducing cross currents depends on the number, size, and hydraulic efficiency of the

ports. Franco (1976) suggested that, in general, the total cross-sectional area of port openings

in the upper guard wall should be equivalent to the cross sectional area of the approach channel

affected by the lock and lock walls and that the top of guard wall ports should be 4 to 6 ft belo

the bottom of a loaded tow to minimize pull of the tow toward the wall . Franco als

recommended the channel bottom between the guard wall and bank be near or lower than the

bottom of the ports to reduce velocities and prevent build up of head on the landside of the tow

When ports extend down to the stream bed, an alluvial bed should be protected against scour 

Velocities in the upper approach in the Dardanelle model appeared to be low enough (1 to 

ft/sec) and sufficiently well aligned with the lock so as to not interfere with tow movement.

Typical patterns and velocities in the lower Dardanelle approach are shown in Figure 9 .2

based on model studies (U.S . Army, Corps of Engineers, 1960) . Model studies indicated tha

ports in the lower guard wall were not effective in reducing eddy action downstream of the end

of the wall . Based on model studies, all Arkansas River locks have ported upstream guard wall

and solid downstream guard walls.

9.2Lock and Dam2,Red River

Lock and Dam 2 on the Red River (lift 24 ft) was completed in 1987 . After completion

navigation conditions in the upstream lock approach were difficult at medium to high river flows

when mean channel velocity was about 7 ft/sec and maximum velocities were in the order of 10

ft/sec . One of the alternative guide wall designs model tested is shown on Figure 9 .3a . Th

upstream guide wall constructed is a 700-ft cellular structure with ports 35-ft wide (except for

the most downstream port) . When the project went into operation, flows were concentrate

through the most downstream ports, and at some discharges, velocities were sufficiently high

through the ports to pin tows against the wall . It was concluded that :

a. Flows through the ports should be redistributed to be more uniform .

b. Lateral flow distribution in the upstream reach of river should be altered to reduce th

percent of total river flow entering the lock approach.

Robertson (1995) reported the following remedial measures were taken . A system o

submerged dikes was installed upstream from the guide wall to force flow away from the lock

side of the river ; top of dikes was 14 ft below normal pool level. Flow conditions in th

upstream approach improved immediately, and much less debris collected in front of the upper

miter gates. In the next high-water season, river pilots reported it was much easier to enter and

leave the lock with the dikes in place . The effect of such dikes is shown schematically in Figur

9.3b. Similar submerged dikes were installed initially at several Arkansas River locks having

similar approach problems .

9-2
c

C

Unequal distribution of flow through ports in the guide wall was still a problem, howe

Prototype measurements indicated that 60 percent of the flow entering that portion of r

bounded by the guidewall passed through the downstream 25 percent of the wall . To redistr

the flow, concrete blocks were placed in the three full-sized ports at the downstream end of 

wall, reducing flow through those ports about 50 percent . Approximately 38 percent of 

entering flow now passes through the downstream 25 percent of the wall, and the current pro

has been solved.

The Red River Waterway is discussed further in Appendix B.

9.3 Robert S. Kerr Lock and Dam. Arkansas River.

The Robert S . Kerr Lock has a 110- by 600-ft lock chamber on the left bank wi

maximum lift of 48 ft and a four-unit powerhouse on the right bank . Embankments ab

maximum pool level connect the lock and dam to high ground on both banks . The ogee spil

has 18 tainter gates, each 44 ft high and 50 ft wide . General reach conditions prio

construction of the project and limits of the model are shown on Figure 9.4a. The struc

layout and details are shown on Figure 9.4b; it will be noted that the 600-ft upper guide wall 

25-ft diameter sheet pile cells on 50-ft centers . Thus, the ports in the upper guide wall ar

ft wide and 37 ft high.

Navigation conditions in the lock approaches were studied in a 1 :120 fixed bed mo

Model tests indicated (Franco and Glover, 1968) that with the original design :

a. Downbound tows approaching the lock would have difficulty because of high c

currents near the end of the upper guide wall caused by flow from the left overbank mo

across the upper lock approach to the spillway, Figure 9 .5 .

b. Upbound tows approaching the lower guard wall would experience considera

difficulty in the lower approach due to the strong eddy that formed with the powerhous

operation and no flow through the spillway . Velocities as high as 2.9 ft/sec cut across 

navigation channel near the end of the lower guidewall, Figure 9.5 . No problems should 

encountred in the lower approach with the spillway in operation, Figure 9 .5 .

c. Tows passing under the bridge downstream of the lock would experience s

difficulty.

Modifications (Plan C) in the model indicated that safe navigation conditions could 

obtained in the upper approach by extending a fill from the left dam embankment at least 3

ft upstream (top of the fill would be above the flow line for the maximum navigable dischar

Figure 9 .6 . The fill along the left side of the upstream lock approach forces cross currents 

flow from the left overbank to move across the approach channel farther upstream wh

downbound tows can maintain sufficient speed and approach the upper guide wall with

difficulty.

Eliminating ports in the upper guide wall (Plan C-1) increased size and intensity of 

eddy along the riverside of the fill, Figure 9 .6b. There was a tendency for tows to be mo

away from the wall, making it difficult for them to align to enter the lock. With ports in t

9-3
upper guide wall, tows had less difficulty in aligning for entrance than with a solid wall, but 

capacity of the ports could be reduced significantly from that of the original design .

The adverse effects of the strong eddy in the lower lock approach with the powerhou

operating and no flow through the spillway was reduced by modifying the right bank downstre

of the powerhouse and extending the lower guard wall with a 550-ft long rock dike . Curre

and velocitiies with the powerplant operating with and without spillway discharge are shown 

Figure 9.7 . Extending the guide wall reduced the intensity of the eddy in the lower approa

with the powerhouse in operation and gave tows entering and leaving the lock addition

maneuvering area. The small eddy between the guide wall and the left bank did not appear 

be of sufficient intensity to affect navigation .

9.4 Olmsted Locks and Dam, Ohio River

Olmsted Locks and Dam (lift 21 ft) is located on the lower Ohio River, 16 .6 miles ab

the confluence of the Ohio and Mississippi Rivers. Tailwater at Olmsted Locks is not affect

by a downstream navigation structure ; open-river conditions prevail downstream . Tailwa

elevation ranges widely and is influenced by Mississippi River backwater levels . There are t

110- by 1200-ft locks with a 21-ft lift, Figure 7 .4. The emptying system consists of four wa

culverts from the two locks (located in the land wall, middle wall, and river wall) emptying in

a single . outlet structure in the river, Figure 8 .36 .

A 1 :25 scale model of the outlet for Olmsted Locks was used to investigate flow pattern

velocities and water levels in the vicinity of the outlet structure (Stockstill, 1992) . The mod

reproduced the lock emptying system downstream of the emptying valves, approximately 115

ft of the Ohio River, beginning 650 ft upstream of the outlet, and approximately 50 ft of t

width of the river . Three steady state flow conditions were tested : land lock emptying ; ri

lock emptying; and both locks emptying simultaneously . Unit river discharge was 57 cfs/ft, 

the maximum outlet discharge was 10,500 cfsllock (21,000 efs with both locks emptyi

simultaneously) . Depth-averaged velocities for the three conditions are shown in Figure 9 

Worst-case conditions also were investigated, with a unit river discharge of 130 cfs/ft along t

lock wall and both locks discharging for five hours (prototype) . Observation of flow patte

indicated no adverse flow conditions in the vicinity of the outlet structure . Model studies 

determine stability of riprap to be placed in the vicinity of the outlet structure, Figure 9 

indicated that material with a D 50 size of 24 inches and the gradation shown in Figure 9 .9b wo

be stable for these extreme flow conditions .

The Olmsted project is discussed further in sections 7-2 and 8-22 . .

9.5 Canal surge and tow squat

Temporary Lock 52, Ohio River . An investigation was made in 1985 of navigat

conditions at the temporary 110- by 1200-ft lock, Figure 9.10, constructed at Locks and Dam 

Ohio River, in 1969 (Maynord, 1987) . The new lock is landward of an older 600-ft lock, 

normal lock lift is 12 ft . This temporary lock operated for many years without a draft restricti

and without damage to the lower miter gate sill . However, there is only 11 ft of depth over t

9-4
lower sill, and one pilot, either pushing a heavily loaded tow too fast or with excess

acceleration while over the sill, damaged the lower sill and put the lock out of operatio

Following the accident, a draft restriction was strictly enforced . When the gage falls below 

ft (12 ft of depth over the sill), tows with over 9 .25 ft of draft are required to use the 600-ft lo

Drafts of all barges were measured, which increased lockage time and was time consumi

Operators felt that a speed restriction combined with a draft restriction might be more effecti

Early in the study, a limited prototype investigation was made to observe tow moveme

and to measure speed and squat . Maynord (1987) reports the following observations :

- Towboats operating on the lower Ohio River have a wide range of power, up to 85

horsepower; larger boats had Kort nozzles with a steering rudder behind the wheel and 

backing (flanking) rudders in front . Smaller boats had similar rudders, but open wheels (no K

nozzles) . Connections between the towboat and tow were made in different ways, and there w

no consistency in arrangement of empty and loaded barges .

- All pilots used very low headway entering and leaving the lock, with power usual

set at 100-200 wheel rpms. Pilots of larger boats cut the power off while the boat was over t

lock sill . Very little and very infrequent rudder was applied once the tow was lined up with 

lock and sheltered by the approach walls.

-. Squat was a maximum (up to 0.8 ft) when the towboat was accelerating 

decelerating. While under way at constant speed, squat ranged from 0 .1 to 0.65 ft. Squat w

less than 0.1 ft when coasting .

- Tows entering the lock from downstream maneuvered slowly until the bow was in t

confined section and the tow was aligned with the walls . Tows then came ahead with signific

speed.

In the past, the downsteam culvert valve was often closed after the lower po

elevation was reached in the lock, but operators are now leaving the valve open while tows m

in and out of the lock.

- Operators generally lock three tows up and three tows down when tows are waiti

- Operators stated that some towboats have drafts in excess of 9 ft and that tows oft

have towboats too small for the load being pushed .

Tow squat is the vertical drop of the tow due to motion, measured from the still wat

level. Maynord (1987) describes four phenomena causing squat as follows :

a. Displacement squat occurs in confined waterways when water adjacent to the tow 

set in motion by displacement of the tow . To maintain the same total energy, the water surf

drops an amount equivalent to the kinetic energy of the moving water . It is related to tow spe

ratio of tow cross-sectional area to channel cross-sectional area, and depth of water . Propel

speed is unimportant .

b. Piston squat occurs in locks where the channel is blocked at one end ; it is significan

different for tows entering and exiting a lock, Figure 9 .1 la. Entering tows pile up water in fr

of the tow, giving them extra depth, and piston squat does not occur . For tows leaving a lo

the volume behind the tow can increase at a greater rate than the return flow under and aro

9-5
the tow, and water depth behind the tow can decrease causing squat . This is not related t

propeller movement.

c. Propeller squat is caused by the ability of the towboat to pump water from beneat

itself faster than it can be replaced . It is significant only in shallow water and is increased by

barges upstream which can block the supply of water to the propellers in a confined waterway

such as a lock.

d. Moment squat is caused by the offset between the force produced by the propeller

and the force at the connection with the barges, Figure 9 .llb . It is greatest with empty barge

and produces a moment that tends to force the rear of~ the towboat down .

Maynord (1987) reported that model studies using both self-propelled tows and a towing

apparatus showed that:

a. Squat for entering tows is caused by different parameters than those causing squat for

exiting tows . Maximum squat for almost every self-propelled test (entering and exiting) was at

the stern of the towboat .

b. For entering tows, tow speed is not important, and displacement, piston, and momen

squat were either small or inapplicable . Propeller squat is the primary mechanism producin

squat.

c. For exiting loaded tows, propeller squat is an important mechanism . In acceleratio

tests, during which all tows approached the sill at the same speed, there was increased squat for

increased propeller speed .

d. Entry speed can be very irregular due to translation waves from tows moving from

unrestricted water into confined water.

e. Unloaded exiting tows can have enough squat to strike the lower sill when operating

at high propeller and tow speed and low clearance between tow and sill.

f. Emptying valves should remain open during tow entry and exit . Squat is considerabl

less with the valves open for equal tow speeds, Figure 9 .1.2a and 9.12b.

g. Large towboats are most likely to strike the lower sill because they have the greatest

draft and the greatest potential for producing propeller squat . Small towboats may be susceptible

to striking the lower sill because they may have to use increased power while in the vicinity of

the sill .

Maynord (1987) pointed out that the primary weakness of the model study was that onl

one towboat and pilot were used and that the squat/propeller speed/draft relationships for the

model towboat cannot be strictly applied to all prototypes . However, identifying propeller spee

as the primary variable controlling tow squat in locks can be useful in solving prototype

problems.

Bay Springs Lock and Dam . Bay Springs Lock and Dam is the uppermost navigation

structure on the Tennessee-Tombigbee Waterway, connecting the two rivers. It is located at th

southern end of the Divide Section of the waterway and creates a pool extending through th

divide cut to Pickwick Lake on the Tennessee River . The Bay Springs project includes a rock-fil

dam, a 110- by 600-ft lock, and a canal extending downstream, Figure 9 .13. Bay Springs Loc

9-6
0

0

has a normal lift of 84 ft ; maximum lift of 92 ft; and minimum lift of 78-ft. The canal h

300-ft base width, depth of 13 ft, and is excavated in rock for approximately one 

downstream from the lock, with side slopes of 4V on 1H .

Surge conditions in the canal were investigated in a 1 :80 undistorted model (Tate, 1

A tow consisting of nine barges loaded to 9-ft draft (prototype) was used with a motor

towboat. Design of the original outlet diffuser system is shown in Figure 9.14a . A 1-mi

valve opening and 11 .9-minute emptying time were used in initial model tests, and this oper

produced a 1.9-ft high translatory wave with a steepening leading face which transformed 

an undular wave with crests increasing to 2 .6 ft above normal pool . Forces measured on 

moored downstream indicated conditions would be very hazardous for navigation . Observat

indicated that a tow moving upstream at approach speeds of 2 .7 to 4 miles per hr woul

transported 60 to 120 ft downstream by the lock release even with increased power applie

Longer valve opening times were tested, and slower valve opening times significa

reduced wave height and maximum forces exerted on moored tows . A 2-min valve opening 

decreased forces approximately 33 percent ; valve opening times of 4 and 8 minutes were 

slightly better. It was concluded (Tate, 1978) that the undular wave did not form in the m

with valve opening times longer than one minute ; that the slope of the water surface in the 

rather than wave height was a good indicator of forces on a tow ; and that slope of the w

surface was a function of speed of valve opening.

The diffuser design was modified, and the design shown in Figure 9.14b was tested . 

lock and canal were realigned to place the lock guide wall on the right bank of the ca

permitting tows to use the full width of the canal when maneuvering to enter the lock . 

modified design provided a uniform discharge across the width of the canal . Maximum forc

a moored tow was reduced from 170 tons to about 40 tons with a 1-min valve opening time 

to about 20 tons with a 2-min valve opening time

Studies of the relationship between filling and emptying times for longitudinal f

culvert systems in lock models and prototype indicate that prototype locks will empty about 

percent faster than the model . The stage-time relation for Bay Springs was adjusted and t

in the model. The expected prototype surge with valve-opening times of 1 and 2 minute

shown in Figure 9.15. With the 2-min valve opening time, the maximum rate of rise of the 

surface was 0.06 ft per sec with a maximum surge height of 2 .5 ft above normal pool . Fo

on tows did not exceed 36 tons and maintained a uniform rate of loading of approximately 

ton per sec.

Based on model tests (Ables 1978), the recommended emptying times for Bay Spr

Lock are:

FillingEmptying

Valve operating time 1 min 2 min

Model operation 10.5 min 13 .3 min

Prototype (estimated) 8.6 min 10.9 min

9-7
Details of the emptying manifolds (Ables, 1978) are shown in Figure 9 .16.

The intake design with invert at elevation 352, Figure 9 .17, was satisfactory and vorte

free. Tests were made also on a 1 :25 scale model with the invert of the intake ports raised 8 f

but the higher level resulted in the formation of persistent swirls over the intake ports . Based 

experience, persistent swirls in a 1 :25 scale model indicates vortices will occur in the prototy

(Ables, 1978) .

When too much air is admitted to the filling culverts at the control valves, air pocket

form that cause surges when they are released into the lock chamber, and it is, therefor

important to control the admission of air to ensure that only as much air is admitted as can 

entrained as small bubbles. The filling valves at Bay Springs Lock were lowered to elevatio

304 to obtain desired pressure conditions on the .roof of the culvert immediately downstream 

the valves during filling operation when cavitation could occur, and controlled air-vent slots i

the culvert roof 7 ft downstream of the valve admit air to minimize cavitation . The qualitati

effect of air venting is shown on Figure 9 .18. Final adjustment of the air vents must be ma

in the prototype.

Lock and Dam 17, Verdigris River (Choteau Lock and Dam, Arkansas Rive

Navigation Project). Dam 17 is located in the Verdigris River, and Lock 17 is located in a cana

about 3400 ft east of the river, Figure 9 .19. Normal lift is 21 ft ; maximum lift is 24 ft. T

upstream canal approach to the lock is 150 ft wide and 9 ft deep for about a mile, Figure 9 .

(Huval, 1980) . There are wider reaches, with 300-ft bottom width at the junction of the cana

and the Verdigris River and just upstream of the lock to aid navigation and reduce surge effect

Most towboats operating on the Verdigris at the time this study was made were of t

2000 to 4200 horsepower class, and most tows were about 105 ft wide, with 7 to 8 .5 ft draft a

about 600 ft long . Such tows occupy a major part of the canal cross section, Figure 9 .20, a

this causes tows to squat as much as 1.5 to 2 ft below static floating position, depending on to

size and speed . Groundings occurred for both upbound and downbound tows, particularly in th

transition reaches. The squat problem worsened when the lock chamber was filled when 

downbound tow was in the approach channel . Field tests indicated as much as 1 .3 ft 

drawdown one mile upstream from the lock (Huval, 1980).

A mathematical model was used to determine lock filling surge heights along the can

for 15 different canal configurations . Results for the maximum surge amplitude near the end 

the transition immediately above the lock are summarized in Figure 9 .21 . For the maximu

surge amplitude near the end of the transition immediately above the lock, surge amplitu

decreases with increasing canal cross section, and the rate of decrease is greater due to can

widening than to canal deepening . However, clearance under the tow (deepening) is critical 

the time of maximum surge .

Tow squat increases as the square of tow speed, and laboratory and field tests indicate th

self-propelled tows cannot exceed V, (Schijf limiting speed) and usually operate at from 50 

90 percent V,, Figure 9 .22a. The data indicate increasing canal width (and maintaining consta

base depth) will not lessen grounding problems for tows proceeding at the highest possible spe

9-8
0

0

(0.9 V). It was concluded that widening the canal without deepening probably would aggr

the grounding problem .

The effect of increasing canal depth on tow squat (and maintaining constant base wi

is shown in Figure 9.22b. The data indicate that squat at limiting tow speed increases 

rapidly with increased depth than with widening . Data in Figure 9.23 indicate that relative 

increases more rapidly by deepening the canal than by widening ; however, the increase in 

is small and less than the increase in canal depth . Thus, it is more advantageous to deepe

canal than to widen it for a given increase in cross-sectional area.

It was concluded that a 12- by 300-ft canal cross section would eliminate the possib

of grounding, would significantly improve limiting tow speeds, probably reduce transit t

through .the canal, and improve navigation conditions .

9.6 Shoaling

In selecting sites for navigation locks and dams on alluvial streams, consideration 

be given to sediment transport and deposition patterns . Shoaling in the lower lock approac

not remedied, can be a serious and continuing problem, expensive for tow operators in lost 

and requiring periodic dredging . At sites in bends there is a natural tendency for sediment 

moved away from the concave bank, but special training structures may be required at site

relatively straight reaches .

The tendency for shoaling (deposition of sediment) in the upstream lock approach ca

reduced by constructing ports in the upstream guide wall, with the top of ports below the bo

of the tow and bottom velocities through the ports sufficiently high . Shoaling in the l

approach is a more difficult problem . Sediment moves downstream along the lower lock 

(on the spillway side) and is carried into the lower lock approach as the flow exp

downstream at the end of the guard wall and by spillway and power plant flows . S

deposition also occurs due to eddy action in the approach .

Model studies indicated that a properly designed wing dike, extending downstream 

the riverward wall for 400 to 600 ft and angled riverward at about 10 degrees, would re

deposition in the Dardanelle lower lock approach (Figure 9 .24 and 9 .25). The wing dike, 

a top elevation about 2 ft above normal lower pool, permits relatively sediment-free surface 

to pass over the dike while blocking passage of the more heavily sediment-laden bottom curre

Such structures have been effective in reducing dredging requirements at Arkansas River l

(Franco, 1976) .

9-9
Spillway

Power plant

Lock

~~ Lock

Power plant

--*--- Spillway

L	

Figure 9.1 . Flow patterns in upstream lock approach,

Dardanelle Lock and Dam, Arkansas River.

(Spillway discharge : 200,000 cfs ; power plant discharge: 36,000 cfs .)

(Corps of Engineers, 1960) .

A / r 17,- 3 .1JJ 0.4

1 .4 f

11

2i

-1 -5.65?,. . 2 .82.2

Access

(a) Power plant discharge : 36.000 cfs

Figure 9.2 . Flow patterns and velocities downstream of

Dardanelle Lock and Dam, Arkansas River.

(Corps of Engineers, 1960)

9-10

Lock

9 .1-_ 9 .1- --7'3

11 .0 10 .0 9-.1 8 .8 Spillway s-.

9.1~ 8 .4~ 7 .3 -5.5

Power plant --a--: 5 .0 8.1 4 .4
CD

OVERBANK FLOW

Th

TOP BANK J

EL 741

	

ir

f L 11 0

fL j? 'O

_,77nrnnn777nm

q!linirr7l~~

7 UPPER PORTS

	 750' UPPER GUAROWALL

a . Upper guard wall (Shows and Franco, 1979).

lrn7.rmrl

rrrrrf

i t

I

NONOVERFLO W

•MBANKMENT

~~ SUBMERGED

DIKES

W10,

i

i

i

r f4 rt 0

~rrrirrrrran

LOWER PORTS

b. Effects of overbank flow and submerged dikes

(Corps of Engineers, 1980).

Figure 9 .3 . Upstream lock approach, Lock and Dam 2, Red Riv

9-11

	 LIZ 74 1

!L •f0
Figure 9 .4 . Robert S. Kerr Lock and Dam, Arkansas River

(Franco and Glover, 1968) .

9-12
1

1 1

I

i

I

I

I

~

-5.8'^ .0~

58 _661

3 fr

_x.436

/

oe , APPROX. TOP BANK

44,

1 21.4

	/4 /.5 	/T

<s

1

/7

/.T /.7 /.S

7-7- 17 17 iS \ 2

/7

14 16~- 8 --.4

14 /.6 / 9

?g

`=_

19' Lam- 21 , Z0

Z2

_z41,Z

2.3

2.2 --_ _ 2 y~-

2.4 2.3

2~ ~ -

r-~- 26 2 6 26 2 T. - .J.2

'~

2 .7 - Z4 ?.3 ?6

_25

445

2.3

s

S

A

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R-15

-4.8-

6.0

57 . .

s/ 5.8 I6 6

'ON	

4,4

s

/ON J

R-20

60

.3..r

s

a . Spillway release 175,000 cfs ;

powerplant release 55,000 cfs .

•.y0

	

-QA-- i0

OS,	1.0

0,81.0

SLACK

LACK)

m

r

0--

9

,y

6

15

4 .J

t 8 t~-

Figure 9.5 . Velocities and currents, original design,

Robert S . Kerr Lock and Dam, Arkansas River

(Franco and Glover, 1968) ._

9-13

i . .4.5

S7 ~Q~

7 .4

- 63-" -6-• 5

-.68- .6.8-

-d7-64= :=46.7 _66 . .

6

64 - 6O - 

70 73 

~01 16

ION J

b. Spillway release 0 ;

powerplant release 55,000 cfs

I
'~--~"- -UPPER\ POOL El.

r

APPROXIMATE TOP cfgnin

R-i5

436 ~`~- -434

0,6 p4

a. Plan C - 3000-ft left bank embankment ; ports in upper guide wall .

I

1

IN

I

I

I

-0'0.6

.9

I.

I.

aft

- 12

23

zi

2__j.9J

- -3 ^T 6' '-

-J

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1s

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-3.2

- JUPPER POO EL 46 .0 FT MSL

EL 456

b. Plan C1 - 3000-ft left embankment; no ports in upper guide wall .

Figure 9.6 . Velocities and currents, Plans C and C1,

Robert S . Kerr Lock and Dam, Arkansas River .

Spillway release 175,000 cfs ; powerplant release 55,000 cfs .

(Franco and Glover, 1968).

9-14

l
C

a, Spillway release 0

Powerplant release 55,000 cf

Taiiwater elevation 418 .0 ft m

s

Spillway release 175,000 cfs

Powerplant release 55,000 cfs

Tailwater elevation 431 .2 ft ms

Figure 9.7 . Velocities and currents, lower lock approach,

with modifications to improve navigation conditions,

Robert S. Kerr Lock and Dam, Arkansas River

(Franco and Glover, 1968) .

9-15
IN

-- --- --- --- -

19 - ..0- a.- 7 7.2 - &2r

O o0 0M71

a.--

4 -

at~~L6•-~" 7.0"~

a 2w

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*01G .(.000(5 460 01 000707706 PUT P01 0(22000 .

-L3 1.5-

2 .0- 17-

DEPfli-AVERAGED VELOCmEs

LAND LOCK 8APTYWO

Tale 1DO M CUTLET

TALWATER EL 275

FMVEl1151108C>fAA0E 57 CM/Fr

10.500 c 's TFii000H OUTLET

100

100

.- _ '0?a_MT--- •_ _,__•_

~eu701rra

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W PUT

• 00

51- 51- 56^'- 6.2--

41- 501 6,3- 0.9-

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110161 1(6001(5 4 K 01 000701200 OUT 0Q 6(70110.,

200

WM *0.001" A a w 000001WO FM PM =OHM

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a 260

0*Tp Way

DEPTH-AVERAGED vEL.OCTuEs

FbVER LOCK EMPTYING

TYPE I DESIGN CUTLET

TALWATET EL V9

froTSI 1M C1 MOMe 57 C•FB/FT

14500 CPS THROUGH OUTLET

DEPTH-AVERAGED VELOCITIES

BOTH LOCKS B4PT ICVG

TYPE 1 Deam OUTLET

TALWATT4t EL 279

MEN UNT DIBCNAFit,T: 57 CF8/FT

21000 cFO THTOUOH cU11.ET

Figure 9.8 . Depth-averaged velocities, river outlet,

Olmsted Lock and Dam, Ohio River

(Stockstiil, 1992).

9-16

0000 U10T • - - • - - ^ . -

10- .,2 •- .4

53•r a7- 7A--

000011(0 ..0-- .7- .3/

..2-- .A~ ..9~ 7A 51'~aT-'

0.00

EL 260

12- - 12_ 9.0

5

lrt/~ 11r

Is- 2.6

LI

7.0 L9~

L .- 1~-

27 00 5W

0.!

11-

EL 235

al--

17- 39-

000 011(0 17- .0-

16- 19~

ROW

l .- 12~

L9-

10

2.2-

17 -
a. Riprap blanket at outlet.

b. Gradation of Type 2 riprap .

Figure 9.9 . Riprap protection at river outlet,

Olmsted Lock and Dam, Ohio River

(Stockstill, 1992) .

9-17
638'

tIOCKFLOOR

EL 278

LOWER

MITER

GATE

SILL EL 279

DOWNSTREAM

APPROACH

EL 278

DOWNSTREAMCOCVERT

ANOOISCNAROE

MANIFOLD

EOTTL 17s

rOP EL-289

D

LOCK,FLOOR-l' ---PORTS- 42r .50

ETAIL

(SEE NOTE)

b. Details of lock and discharge culvert .

mS

4

y

L270'PINTLE TO PINTLE

PLAN

ROVE, ILEVATIONVIEW186TWEINEACH OFTNE

71 CENTEKMOST CELLS OF THE 40 CELLS

FORMING LANOWANO LOCK WALLI

~~""~~t

l~l~ltllrl~l~ 1~1l11~1~1

:~

.~ LOCK FLOOR

EL 278

1,200-FT LOCK

- --. w'a .~3~i~I~3~IMI~ISi~I~I~3taI~3r+MfrI~r~I~3<rl~I~r~I~itrll ;~I~;~Mw

M

O

CHANNEL

EL 278 -,

f FLOW

a. General plan .

Figure 9 .10 . Temporary Lock 52, Ohio River

(Maynord, 1987) .

9-18

DETAIL A

NAVIGABLE

PASS

O

a

N

O

N
1

REACTION

FORCE

WITH

BARGES

3

3

W 2

a

a

s

E

S 1

OFFSET CREATES

CLOCKWISE MOMENT

PROPELLER FORCE

TIguc . 4 . No . .nc squat

•

S/E

a. Entering tows.

Figure 9 .12 . Comparison of squat for entering and exiting tows

with and without emptying culvert open

(Maynord, 1987) .

9-19

UPPER MITER GATE

-WATER LEVEL BEHIND TOW

LOWER THAN STATIC

A. 50 . NLEVEL PRIOR TO MOVEMENT.

a. Piston squat.

I

I

b . Moment squat.

Figure 9 .11 . Squat mechanisms (Maynord, 1987) .

NOTE : SP ED REPRESENTS AVERAGE

SP

ISO

OVER SILL FOR THE POINT ON

THE TOW HAVING THE MAXIMUM SQUAT

0

2 3 t

TOW SPEED. FTISEC

1

LEGEND

•WITH CULVERT

• WITHOUT CULVERT

2

F

K

C

H

S • •

S

411 f 1

• I

•

•

4 •

0

1 I

0 50100 150 200

PROPELLER SPEEMAPM

4

ORAFT .9.0 FT

DEPTH OVER SILL • 11 .0 FT
r 3

0

O

F7

0

0

3

C .

C

0

3

0 1

3

0

	• i

	I	I	I

NOTE. SPEED REPRESENTS AVERAGE

SPEED OVER SILL FOR THE POINT ON

THE TOW HAVING THE MAXIMUM SQUAT

3

TOW SIEE0. PTISEC

LEGEND

•WITH CULVERT

• WITHOUT CULVERT

•

•

	

.,

•	1	I 0

50 100 I50

PROPELLER SPEED.RPM

DRAFT . •A PT

DEP H OVER SILL .11 .0 PT

b. Exiting tows .

I

Figure 9.12. Comparison of squat for entering and exiting tows

with and without emptying culvert open

(Maynord, 1987) .

9-20
Figure 9 .13 . Bay Springs Lock and Dam, Tennessee-Tombigbee Waterway,

dam, lock and canal alignment

(Tate, 1978) .
WX/I'

Cm YCATI

f as ?*V7L‚

CL 7uu 0 --

C& zoo 0

v

u

( CMIr,,,c i CCaAC

a . Original design .

PLAN VIEW

b. Modified design .

Figure 9.14. Outlet diffusers and lower lock approach,

Bay Springs Lock

(Tate, 1978).

9-22

IL. I)7

IV

0

< _

d

O
I

F

W

V

4

z

F

W

333

332

331

330

W 333

332

331

330

a. 1-minute valve opening time .

S6 7 6 9 -IO""-.11-l2^` 7 13"" Ia

IS 16 17 16

TIME. MINUTES

b . 2-minute valve opening time .

Figure 9 .15 . Expected prototype surge, no tow,

Bay Springs Lock

(Tate, 1978).

9- 23

LEGEND

STATION I + I I DIFFUSER CENTER LINE.RIGHT SIDE

STATION I + I I DIFFUSER CENTER LINE. LEFT SIDE

STATION 10+00

STATION 16 + 00

STATION 26 +00

STATION 34 +00
OIL

NIONE

r

F .

!I l71

II LEFT WALL 1 '45

, - i

ise

-T

A--

A-.

NIGHT WALL

wl

L':%

r ,'-' ..'" -4

OCR

M

USE.

	rie

I

SECTION t .A

Figure 9.16. Emptying system, Bay Springs Lock

(Ables, 1978) .

9-24
4

-

![ow -

4",	

1

~!\\

	

rom-4ECM MULL~l. .ao

*,

IMN. Dula WIM

r~r"j

'nil C, n'

1100 IC 7owwTU

I	 =r	

1.

a . Plan.

40N&

b. Left culvert elevation .

9.17. Intake system, Bay Springs Lock

(Ables, 1978) . -

9- 25
N

3

W

z

0

i

3

OWNO	

OIAMETE OF 11-6

AIR ORIFICE IN TOP OF ONE ON

VENT i1.01/Z DIAMETERAR VENT

IAOVLDIAMETER IN

ONE AIR VENT

LOCATION AIR VfWT

LOwƒP POOL ELJJQO

oOULKNEAO

SLOT SEALED

ƒL J12.0

PRfSS`~ ,~'. .

SCHEMATIC OF

FILLING VALVE CULVERT

Figure 9 .18 . Effect of air venting on culvert roof pressures downstream

of culvert filling valves, Bay Springs Lock

(Ables, 1978) .

9-26

I-u I12•

DIAMETER IN EACH

OF 2 AIR VENTS

31b

--- - ---------_--_--

- CULVERT.. ROOF EL J/2.0 OBSERVED AVERAGE

JIO

305

-

LOW

300

- CULVERT INVERT EL 298.0

/ /

29 it i I l i

dl'I~, hl ~l v 's [-MIN NORMAL

oflNlo of el IVALVE OPERATIONS

x90

111 0'

35

I

HIGH

310

CULYERT ROOF EL 3/2.0

/ /

gVERAG

ƒ /-'

RV

•

300

CULVERT INVERT EL 298.0'

2aa

290 ,

2-MIN NORMAL

VALVE OPERATIONS
L&D 17

(Chateau)

J% Caoo..

A

L LQO

18

OZARK

)

(L&012) KAN$4

L d OAIL 0E0L

13

HEAD OF

NAVIGATION

HEY8URN

raw

TULSA

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F.IP,NNW

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.

EUFAULA

F. .16 N

TORT

8$O

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MARKHAM

FERRY

TENKILLER

FERRY-.-,

14 . ~`~

O

I

v to

I`' L 3 0

ROBERT s 10 KERR v

NL .

a. General map .

b. Project layout .

Figure 9.19. Location Maps, Lock and Dam 17, Arkansas River Navigation Projec

(Huval, 1980) .

9-27
O

n

i

a

a

1 .3

1.A

1.3

1.1

1 .0

515

In

S

rA 510

0

r 505

W

W 500

1

100'

I

3

50'

I

NAVIGATION

CHANNEL 50'

I

100'

I

EL 511

8.3 X 105•

9OWSECno/)

T

EL Sot 5 ~ ~

Figure 9.20. Tow in canal, Lock and Dam 17,

Arkansas River Navigation Project

(Huval, 1980) .

7

AREA. 100010 R

Figure 9 .21 Maximum computed surge magnitudes at

upstream end of transition above lock

(Huval, 1980) .

9-28

BASE

~ of

zod

t 601

	 A30 0EOTH

0

12 .0? OEI?H

p 1A.rT O<n. O

1r+T DEPTH

P00'\ 110TH$
L

C

S.

z .

2a

DS

W

0.3

e 0

e

e z

•

TOW SPUD. .TnU

a. Increasing width for constant depth .

•TDB. SILLD. .T/SLC

b. Increasing depth for constant width .

Figure 9.22. Effect of increasing canal dimensions on tow squat .

(Huval, 1980) .

9-29

.

le

i0

I

Vh

.r

0

veQy~
F

m`

•

•

20

C

e

82

1-

W

•

•

40

V

80

0 50100 150

RELATIVE AREA INCREASE, PERCENT

Figure 9.23 Effect of canal size on tow squat at 0 .9 V,

(Huvel, 1980) .

9-30

200

\\~ 9ASE

\\ \\

\\'

.

O

.N NO

\\

\\

I•)

1I'

\\

15

00 ,
Upper pool

Lock

Rock dike to elevation to confine

maximum power plant flow

ME~Mw

L

v

Figure 9.24. Dike to minimize effect of power plant releases on navigation

in lower lock approach, Dardanelle Lock and Dam, Arkansas River

(Franco, 1976) .

Top bank

(a) Plan

Top of lock wall

(b) Section

Figure 9 .25. Wing dike to minimize shoaling in lower lock approach,

Dardanelle Lock, Arkansas River. (Franco, 1976).

	

Top of wing dike

4 2 ft

Low

poo
10. DREDGING

Dredging is a very costly operation and involves many uncertainties that affect proj

cost, including a realistic estimate of the total quantity of material to be dredged 

characteristics of the material as they relate to the dredge production rate (the rate at which so

are dislodged at the dredging site and transported to the discharge point) . Other factors 

affect dredging costs. A pipeline dredge operating in a navigation channel may obstruct tra

unless special arrangements are made . Dredges normally operate 24 hours a day, and if 

dredge site is in or near an urban area, noise may preclude night operation . Weather condit

may also limit operations under some circumstances .

Costs and potential environmental impacts are fundamental considerations in evaluat

alternative dredging and disposal methods and disposal sites . Many factors must be consid

in developing a dredging operation, including

a. Determining the quantity of material to be dredged initially and the frequency 

quantity of future maintenance dredging .

b. Sampling to determine the physical and chemical properties of material to be dred

to ensure that the appropriate type of dredge is used, to assess dredge production rates so t

time and cost estimates are realistic, and to identify any pollutants in material to be dredge

c. Selecting the appropriate dredge type and size, disposal method, and disposal area 

ensure environmental protection.

d. Identifying adequate disposal areas for both initial and future maintenance dredgi

considering the physical and chemical properties of the dredged material .

e. Long-term management of disposal sites to maximize storage volume and benefic

use after the sites are filled .

Dredging for navigation channels is categorized as either initial new constructio

maintenance dredging to restore authorized channel dimensions (depths and widths), as foll

a. Initial construction dredging is dredging to authorized channel dimensions plus 

allowance for overdepth dredging to compensate for inaccuracies in the dredging operation 

b. Periodic maintenance dredging is dredging performed on a regular basis, for exam

annually following the major flood season, to restore authorized dimensions, with the expectati

that authorized dimensions will be maintained by the river until the next flood season .

c. Aperiodic or occasional maintenance dredging is done on an "as needed" basis w

channel dimensions have diminished to where they limit navigation.

The objective of maintenance dredging is to provide authorized project depth and wi

at all times in the navigation season . In general, most maintenance dredging in inland waterw

is required after river stages fall rapidly on the recession of flood hydrographs, when velocit

decrease and coarser sediments are deposited. To minimize delays to shippers, dredg

equipment (both government-owned and privately-owned under contract) is available to m

quickly to shoaled areas . Priorities in maintenance dredging usually provide that when a num

of crossings have shoaled to where navigation is affected, the shallowest crossings are dred

10-1
first (when this can be done without excessive movement of dredging plant) . This increas

usable depth throughout the waterway, and navigation benefits immediately .

In some cases maintenance dredging includes dredging beyond authorized dimensions fo

"advance maintenance" in critical, fast-shoaling areas, Figure 10.1 . Such over-depth dredging c

result in lesser overall dredging costs and increases reliability of project depth .

Shoaling and maintenance dredging can be reduced by operating criteria to graduall

decrease flood control releases from reservoirs on hydrograph recession . For example, elev

of the upper Arkansas River basin reservoirs are operated to minimize shoaling problem

downstream of the navigation locks and dams on the Arkansas River while meeting criteria fo

releases for flood control, hydropower, and recreation . The operating criteria are complex an

are related to season of the year, storage in the flood control space of each reservoir, and sto

location and magnitude. The reservoirs are operated so that flood releases gradually taper off o

the recession of flood hydrographs and specific targeted rates of discharge reduction are attain

at the Van Buren gage . As flood releases drop from 105,000 to 75,000 cfs and from 75,000 t

40,000 cfs, the decrease in flow is limited to not more than 20,000 cfs in 24 hours . From 40,0

to 25,000 cfs, the target taper is a uniform decrease in flow over a 21-day period .

Maintenance dredging can also be reduced by hinged pool operation, as discussed late

in this section and in Appendix B .

10.1 Arkansas River Dredging

Alluvial rivers typically follow a meandering, shifting alignment and are wide an

shallow: Canalization of such rivers generally requires channel rectification and stabilizatio

work, as well as the construction of navigation locks and dams, to develop a stable channel o

adequate navigable depth . Channel training structures are used to modify the curvature of sha

bends and reduce the tendency of the river to shoal in crossings, Figure 10 .2 . Cutoffs a

constructed to eliminate bends of small radius that would be difficult or hazardous for commerci

traffic. Such cutoffs usually involve excavating a pilot channel (sometimes by dredging) of smal

cross section that is widened by action of the river, Figure 10 .3 . The old bendway is cut off a

the upstream end by a closure structure to prevent sediment deposition in the old channel, b

remains 'open at the lower end for recreation access and environmental enhancement .

The lower Arkansas River, in Arkansas, carried a heavy sediment load prior t

construction of the Arkansas River navigation project which includes large upstream multipurpos

reservoirs that trap much of the sediment load previously transported to the lower river . The

reservoirs and stabilization and rectification works were essentially complete prior to constructio

of Dardanelle Lock and Dam, one of three locks of medium lift (54 ft) on the lower river, Figur

10.4 . The upstream reservoirs had already significantly decreased the natural sediment load wh

construction of Dardanelle was begun in 1959 .

Under preproject conditions, the suspended sediment load at Dardanelle averaged 100 

million tons per year; this was estimated to be reduced to 16 million tons per year under projec

conditions . It was expected that about 60 percent of the sand load entering Dardanelle reservo

10-2
C

as to minimize loss of sediment-transport capacity below the structures.

Pools 9 through 2 downstream from Dardanelle Dam have very different characteristi

at normal pool level with regard to:

a. Storage, ranging from 110,000 ac ft at Pool 2 to 32,000 ac ft at Pool 8 .

b. Pool length, ranging from 33 .2 miles at Pool 2 to 15 .8 at Pool 3 .

c. Surface area, ranging from 10,500 acres at Pool 2 to 3700 at Pool 3 .

d. Average pool depth, ranging from 12 .4 ft at Pools 3 and 4 to 7 .6 ft at Pool 8 .

e. Relationship of normal pool level to the 10,000 cfs flow line .

f. Minimum discharge at which all spillway gates are fully open, ranging from 80,0

cfs at Dam 8 to 280,000 cfs at Dam 2 .

All these factors affect the efficiency of stabilization and rectification work in providing a sta

navigable channel of adequate depth .

There was significant initial dredging as a part of project construction at the heads 

Pools 9 through 2, including 17 million cu yds in Pool 9 immediately below Dardanelle Da

to hasten development of an equilibrium degraded channel that would provide navigable dep

with a minimum of maintenance dredging and meet the scheduled dates for initiating navigatio

Almost all maintenance dredging of the lower Arkansas River has been in the heads 

the low-lift pools, at the approach to the next lock upstream, in relatively-long straight reache

reaches of flat curvature, and long crossings. Except for Pool 2, the bulk of the maintenan

dredging was in the early years of project operation prior to 1976 . Shoal areas at the head e

of Pool 2, Figure 10 .5, are representative of areas requiring maintenance dredging . Pool 2 

had the highest rate of dredging of all pools and accounted for 36, 63, and 72 percent of 

maintenance dredging in Arkansas in 1973, 1986, and 1993, respectively .

Additional contraction was added in some reaches of the pools after the project went in

operation to minimize maintenance dredging and provide more reliable navigable depth . T

authorized channel depth in the Arkansas River is nine feet ; authorized channel width is 250 

at project depth.

10-3
Maintenance dredging was negligible in the 1978-1984 period in Pools 9 through 3

averaging about 150,000 cu yds per year . Studies indicated that deposition in Pool 2, wher

maintenance dredging averaged 430,000 cu yds per year in the 1978-1984 period, is probably

more related to pool characteristics than to design of the stabilization and contraction works 

Pool 2 is significantly longer and has more storage at normal pool level than Pools 9 through 3,

and it is subject to open-river flow conditions more rarely than the other pools (spillway gates

fully open about once in seven years, on the average, compared to annually at the other pools

(Petersen and Laursen, 1986).

Schmidgall (1981, 1985) examined maintenance dredging on the Arkansas River as relate

to streamflow and concluded that the amount of dredging required in most pools is related to

volume of flow . His data relating annual maintenance dredging in the State of Arkansas (the

lower reach of Pool 13 through Pool 2) to annual streamflow at Van Buren are shown in Figure

10.6a . His data for the total system for 1969 through 1994, shown in Figure 10 .6b, indicate tha

maintenance dredging has decreased significantly with time .

Cumulative dredging volume from when the project became operational in 1969 through

1984 is shown in Figure 10 .7 for two reaches: Pools 9 through 3 and Pools 9 through 2 . Data

in the figure indicate that, if one disregards dredging in Pool 2 (on the basis that it is atypical of

pools downstream of Dardanelle), annual dredging decreased significantly with time over the

period of study, and was at a relatively constant and negligible rate of 780 cu yds per 100,000

ac ft of flow (or 150,000 cu yds per year) for the period 1978-1984 . The data also clearly

suggest that deposition problems in Pool 2 are of a different order of magnitude (and probably

of different origin) than those in Pools 9 through 3 .

Maintenance dredging on the Arkansas is initiated whenever depths in the navigation

channel become less than the authorized 9-ft depth . Typically, maintenance dredging is to a

depth of 12 ft, including 3 ft of overdepth dredging for advance maintenance to allow a time

period for sediment buildup before the 9-ft authorized depth is no longer available and

maintenance dredging must be repeated . The objective is, to provide authorized navigable depth

100 percent of the time to the extent feasible . Dredging typically begins on the hydrograph

recession at flows in the order of 120,000 to 70,000 cfs (flows that carry a significant sediment

load with depths considerably in excess of authorized depth) to minimize potential interruption

of navigation.

The Little Rock District awards two maintenance dredging contracts in January each year

for work in the calendar year, and contracts run concurrently . Two cutterhead dredges are used,

one assigned to Russellville (Dardanelle area) and the other assigned to Pine Bluff, but both work

in any area of the river, as needed. In the period 1979 through 1989 (including three years in

which the flow volume exceeded 30 million acre-ft), dredging in Arkansas ranged from 329,000

yds3/yr in 1980 to 5,953,000 in 1988 and averaged 1 .94 million yds 3/yr. In the period 1984

through 1994 (including six years in which the flow volume exceeded 30 million acre-ft),

dredging in Arkansas ranged from 1,314 million yds3/yr in 1984 to 4,785 in 1988 and averaged

2.27 million yds3/yr .

10-4
C

C

10.2Mississippi River Dredging

The Mississippi River has a navigable length of 1811 miles . Authorized cha

dimensions are 9 by 150 ft from miles 857 .6 to 853.4 ; 9 by 200, ft from miles from 853 

815.2 ; and 9 by 300 ft downstream through the Vicksburg District . (Mileage above the m

of the Ohio River at Cairo is measured as "miles above Cairo ;" mileage below the conflu

with the Ohio is measured as "miles above Head of Passes" at the mouth of the Mississ

River.) The river is canalized downstream to the vicinity of St . Louis, Figure 10.8 .

The St. Paul District, Corps of Engineers, is responsible for the Upper Mississippi R

downstream to below Lock and Dam 10 (mile 857 .6 to mile 614) . Dredging is accompli

with a 24-in cutterhead dredge owned by the District (and loaned for work in other District

well) and through annual one-year contracts with firms using mechanical draglines . In the 1

1989 period, maintenance dredging averaged 750,000 cu yds per year, 600,000 by the cutterh

dredge and 150,000 by contract.

The Rock Island District of the Corps is responsible for the Upper Mississippi from 

below Lock and Dam 10 to just below Lock and Dam 22 (mile 614 to mile 300) . M

maintenance dredging is accomplished using the 24-in cutterhead dredge owned by the St. 

District. In the 1986-1989 period, maintenance dredging averaged 570,000 cu yds per year 

1989, 572,000 cu yds of material was removed from nine sites with the cutterhead and 29

cu yds were removed mechanically by dragline and clamshell dredges under contract .

The St. Louis District overseas the river from just below Lock and Dam 22 downstr

to the mouth of the Ohio River (mile 300 to mile 0) . There are four navigation locks and 

in the upper 100 miles of this reach, and open-river navigation prevails downstream . In the 

up to 12 dredges were used in the St. Louis District for maintenance dredging, but currently 

two are used routinely. One is a dustpan dredge owned by the District that usually works in 

open-river reach. A cutterhead dredge is under contract from a private firm to dredge 

navigation pools . The contracts are for one year and are paid on a per-cu-yd basis . Typica

$7 million to $8 million is spent on dredging each year (at $0 .,75 to $1 .00 per cu yd) . Howev

because of the severe drought and record low stages in 1988 and 1989, approximately $23 mill

was spent in each year, and six additional dredges were required . Four were contracted 

private firms, one was borrowed from the Memphis District, and one was borrowed from the 

Paul District (Derrick, 1991) .

The Memphis District oversees the river from the confluence of the Ohio and Mississi

Rivers (mile 953 .8) downstream to the mouth of the White River (mile 599) . In the 1985-

period, maintenance dredging averaged 28 .2 million cu yds per year . Work is accomplishe

four dustpan dredges, three of which are Corps-owned and one under a year-round rental contra

These dredges are used where needed in the St . Louis, Memphis, Vicksburg, and New Orle

Districts.

The Vicksburg District is responsible for the reach of the Lower Mississippi River f

the mouth of the White River downstream to just above the Old River Control Structure (m

599 to mile 320 .6) . The Vicksburg District uses a combination of revetments, dikes, and dred

10-5
material was dredged each year . Most dredging is performed using two dustpan dredges, on

owned by the District (and on loan to New Orleans District much of each year) and the other

under a year-round contract with a private contractor .

10.3 Missouri River Dredging

Construction of six mainstream dams on the upper Missouri River has reduced the average

sediment load from 200 to 50 millions tons per year, with an increase in the percentage of sand

load and a decrease in percentage of silt and clay load . The Missouri River is an open-river

waterway, and there has been no maintenance dredging in the navigation channel above Rulo

since 1969. In the Kansas City District, below Rulo, the channel is contracted by dikes and no

dredging was performed between 1980 and 1988 . However, severe drought necessitated reservoir

releases to be cut back below normal levels in 1988, 1989, and 1990, and depths dropped to less

than the authorized 9-ft project depth . Approximately $775,000 worth of dredging was done in

1988 and 1989 using a cutterhead dredge borrowed from the St . Paul District.

10.4 Red River Dredning

Five navigation locks and dams were recently constructed on the lower Red River, as

discussed in Appendix B . Lock and Dam 1, Figure 10 .9, was completed in the fall of 1984, and

significant sediment problems were experienced at the lock shortly after the project went into

operation . Channel expansion and flow separation created slack water conditions and eddies at

the lock and dam . Studies indicated that structural measures were required to either reduce the

amount of sediment deposition or relocate it into more manageable (more easily dredged) areas .

These measures included construction of dikes in the upstream lock approach channel and raising

the wall that separates the downstream lock approach from the main channel . Periodic deposition

has still occurred after these modifications were made, but it is to a much lesser extent than

previously and in areas that can be easily dredged.

An unusual aspect of the deposition at Lock 1 is that. deposition has occurred in, the

vicinity of the miter gates, Figure 10 .10. In 1990, Vicksburg District rented an 8-in submersible

pump for trial use in removing sediment in the vicinity of the miter gates . The material removed

was fine sand and silt that, when compacted, becomes very hard and difficult to remove . The

pump was used at three locations . The first test site was an area about 85 ft wide by 12 ft in the

downstream direction, and about 6 ft deep downstream from the lower miter gates where material

had settled out during spring 1990 high water ; material was removed to prevent problems in

opening and closing the lower miter gates. The second test area was inside the lock just

upstream of the lower miter gate, measuring 48 by 85 ft and about 4 ft deep . The material had

been compacted by currents, and opening and closing of the miter gates made the material very

dense and hard . Pump production rate at these two sites was about 60 cu yds per hr. The third

test site was between the downstream guide wall and the "I" wall where the material was clean

sand, and the production rate was about 300 cu yds per hour .

As a result of success with the leased pump, the Vicksburg District purchased a 10-in

submersible pump in 1991 . Neilans, et al. (1993) report that the pump was used about three

10-6
0

times a year at each of the three lower locks on the Red River, taking between 2 and 3 day

remove the sediment buildup from each lock.

An advantage of the submersible pump is quick response time . When clearing is need

the submersible pump can be deployed in about four hours if the District's towboat is availab

Maneuverability of the submersible pump makes it particularly well suited for removing sedim

around the miter gates because it can be positioned in corners and along walls without damag

either the lock or the equipment.

10.5 Effect of Hinged Pool Operation on Maintenance Dredging

Hinged pool operation is a spillway gate operational procedure designed to lower nor

upper pool level at a lock and dam to increase velocities through the deeper downstream reac

of the pool, with the objective of decreasing maintenance dredging requirements by mov

depositing sediments farther downstream in the pool and lessening deposition at the head of 

pool, as discussed further in Appendix B .

Locks on the Arkansas River were designed for hinged pool operation and have up

miter gate sills set low enough for tows to enter the locks with the upper pool drawn down f

feet below the normal navigation pool level . This drawdown at the dam decreases depths 

increases velocities through the downstream reach of a pool, thus moving depositing sedimen

farther downstream into the deeper reaches of the pool. On flood recession, after most sedime

have settled out, the normal navigation pool is re-established . Water depths over the sedime

deposited in the downstream reach of a pool are adequate to support navigation without dredgi

Hinged pool operation has been tried at most Arkansas River dams with various degr

of success. In the most successful hinged pool operations, the water level was drawn down o

2 or 3 ft, rather than the full design drop of 5 ft . Good results were achieved in mov

sediments through the navigation channel in the upper reaches of Dardanelle Lake duri

recession of the 1995 floods by using a 2-ft drawdown hinge .

10.6 Dredging Equipment

Modern dredge plant can be classified as either mechanical or hydraulic (or a combinat

of the two) . Mechanical dredges lift the dredged material by means of diggers or buckets 

various design, and hydraulic (suction) dredges pick up material by means of suction pipes 

pumps.

Mechanical Dredges. Mechanical dredges remove loose soft or hard materials b

dipper or bucket of some type and usually operate in conjunction with disposal barges that 

filled with the excavated material and then moved to a disposal site and emptied . Dipper 

bucket dredges are similar in that both operate with the dipper and bucket at the end of a bo

but the dipper is rigidly attached to the boom and the buckets are suspended by cables, Fig

10.11. Bucket and ladder dredges dig the material out using a chain of buckets rotating arou

a ladder, with the buckets discharging onto a conveyer belt that moves the dredged material 

the disposal barge or site . These dredges are not usually self-propelled, but are moved to 

10-7
work site by a tow. They can maneuver in a limited area by using spuds (Figure 10 .11 .)

Hydraulic Suction Dredges ., Hydraulic suction dredges are usually categorized accordi

to the means of disposal of the dredged material (hopper, pipeline, and sidecasting dredges) 

according to the means for picking up the dredged material (cutterhead, plain suction, and dustp

dredges) .

- Hopper dredges, Figure 10.12, are deep-draft seagoing vessels used primarily fo

work in exposed harbors and shipping channels where traffic precludes use of stationary pipelin

dredges. They are not used in shallow-draft waterways in the United States .

- Sidecasting dredges are self-propelled shallow-draft seagoing vessels designed fo

dredging from bar channels at small coastal harbors that are too shallow for hopper dredges an

too rough for pipeline dredges to operate. A sidecasting dredge picks up bottom material throug

two suction pipes and discharges it directly overboard outside the channel prism through 

discharge pipe .

Hydraulic pipeline dredees draw a slurry of bottom material and water through 

suction line and pump the slurry through a floating discharge line to the disposal site . They ar

of three types : dredges with a plain suction intake, dredges with a cutterhead at the forward en

of the suction line to loosen material to be dredged, and dustpan dredges with jets in the hea

to loosen material .

Cutterhead dredges, Figure 10 .13, are the most widely used type in the United States an

are generally considered to be the most efficient and versatile (U.S . Army, Corps of Engineers

1983). The cutterhead dredge has a rotating cutter around the intake end of the suction pipe and

can dig and pump all types of alluvial materials and compacted deposits such as clay an

hardpan. Suction pipe diameter ranges from 8 to 30 in .

Cutterhead dredges consist generally of a cutter, ladder, suction pipe, A-frame, H-frame

pumps, spud frame and spuds, and auxiliary equipment. The ladder carries the cutter

suction pipe, lubrication lines, and usually the cutter motor . Dredge ladders are from 25 to .22

ft in length, and the length of ladder determines maximum dredging depth . Dredging may b

done to depths of 150 ft with standard ladders in light silty materials . The dredge is held i

position or moved ahead with spuds, and the dredge operates by swinging about one spud wit

the head describing an arc, Figure 10 .13d . As the swing is completed, the second spud i

lowered, and the other spud raised to make a swing in the opposite direction, and the dredge

advances forward.

For open-water disposal, only a floating discharge line is needed with a cutterhea

dredge. . The floating discharge line is made up of sections of pipe from 30 to 50 ft long, eac

supported by pontoons. If land disposal is used, additional sections of shore pipe, usually 10 t

15 ft long, are also needed, Figure 10.14.

Dustpan dredges are self-propelled vessels designed for working in noncohesive material

in rivers or sheltered waters with no significant wave action, Figure 10 .15 . Dustpan dredges hav

10-8
C

a wide, flared, flat mouth up to 30 ft across on a rigid ladder, and the dredge head is equipp

with pressure water jets that loosen the bottom material and suction openings through which 

dredged material and water are drawn into the suction line as the dredge is winched forwa

Dustpan dredges cut a channel the width of the head and are limited to making relatively shall

cuts in repetitive passes over the shoaled area . They normally discharge into open water thro

a relatively short pipeline up to 1000 ft long ; a longer disposal line requires a booster pu

They can readily be moved outside the navigation channel to let traffic pass.

10.7 Dredged Material Disposal

The Corps of Engineers has been involved in improving channels for navigation sin

1824, and the first major program for increasing navigable depth by dredging was authorized 

1896 to . provide a 9-ft channel from Cairo, Illinois, to the Gulf of Mexico . For many years 

material removed in dredging operations was considered a waste material except when used 

fill for commercial or industrial development or to fill in dike fields and old bendways in river

However, in recent years, the environmental effects of dredged material disposal has beco

highly suspect in the public view, and much controversy has ensued .

The major problems associated with disposal of dredged material are :

a. Ensuring availability of sufficient disposal area for initial and future maintenan

dredging within a reasonable (economically feasible) distance of dredging operations .

b. Potential, adverse environmental effects associated with disposal of dredged materi

including increase in turbidity, resuspension of contaminated sediments, and decrease in dissol

oxygen.

Disposal of dredged material usually takes place in one of the following areas :

a. Open water.

b. Elsewhere in the river cross section, as in deep troughs in bends that greatly exce

required navigable depth, in old river bends that have been cut off, and in dike fields 

landward of other rectification structures.

c. Dry land in diked disposal areas .

d. Marsh or wetland areas near the river, either with or without retention dikes .

There is increasing interest in the use of dredged material as a resource in the Unit

States because the amount of material dredged each year continues to increase and increasi

urbanization and industrial development near waterways and ports has made it difficult to loca

new sites for dredged material disposal in many areas . Environmental regulations also ha

restricted both land and water disposal options . The cost of dredged material disposal h

increased rapidly in recent years with greater distances from the dredging site to the disposal are

and with environmental controls . Potential environmental impacts can be minimized by using t

most suitable dredge type and dredge size and by careful monitoring and control of dredging a

disposal operations .

10-9
Revetment

Baffle dikes .

Rock escarpment

Ibl Dike system to constrict

channel and concentrate flow

Ial Dike system to realign reach and

prevent bank erosion

Authorized depth

t

\_~/ IOverdepth dredging

Authorized width

Figure 10.1 . Authorized channel dimensions and

overdepth dredging for advance maintenance.

Trail dikes

Ici Dike system to fair out a sharp

bend and concentrate flow in a single channel

FigurelO.2. Dike systems, Arkansas River Navigation Project

10-10
C

MuRkogee(

1L40161~.r 4 i

TENKILLER

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Figure 10 .3. Trustee Bend Cutoff, Arkansas River Navigation Project

(Corps of Engineers) .

500

i

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450 400

PROJECT LOCATION

\tIH.MI(Rt _

OZA

(LADt2) XAKANSAS

300

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ARKANSAS RIVER

LEGEND

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Figure 10.4 . Arkansas River Navigation Project

(Corps of Engineers) .

10-11

Legend :

Top bank

July 1954

Apr . 1957

May 1957

July 1957

Oct. 1958

Nov. 1962

Range

Levee

Structures

Stone fill

Trencrsfill

LA07

LAO4

AA.nw . Pelt

LAD \ Route

A

ti

•

• m

•

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•

0

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1501100 50

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Lock and Dam 3

Cutoff

1

Major dredging

areas

Legend :

z-^-- Trenchfill revetment

Pile structures

‚Major dredging required

0 1

Scale (mi)

2

4

1969 70 7172 73 74

Dredging r FlowI

Notes : Flow at Van Buren. Arkansas

Dredging. 14 .yr average

Flow. 52.yr average

Figure 10.6a. Annual maintenance dredging in Arkansas

and flow at Van Buren gage,

Arkansas River Navigation Project

(Schmidgall, 1981).

10-1 2

75 76 77

Year

78 79 8081 82 83 jAvg.

Figure 10 .5. Major maintenance dredging reaches at head of Pool 2,

Arkansas River Navigation Project

(Schmidgall, 1972).

80

n

T 6

u

60

C C

O O

C 4 .40C,

0

c E

0

m 2

0

r _20>

3

hit ~ C ~ I I

Y
I

69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94

CALENOER YEAR :19~

Dredging =Flow

Dredging and flow averages

Period A. from 1969 through 1994 .

Period B. from 1975 through 1994 .

Figure 10.6b. Annual maintenance dredging in McClellan-Kerr Navigation System

and flow at Van Buren gage

(Schmidgall, 1995).

10- 1 3

A 

PER 10

AVERAG
Figure 10 .7 . Cumulative dredging as a function of discharge,

Arkansas River Navigation Project

(Petersen and Laursen, 1986).

700

e

c 500

0

W 400

300

200

9

0

a

13 I + 2 6 7 a 9 i0 12 14 :6

Cumuiarive dreaginq in million 6uoia yoras

7 6 S 4 3

ii

2

Figure 10.8 . Upper Mississippi River Canalization Project

(Corps of Engineers).

10-14

Ls0

I I I I. I I II

340

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199

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1969

a /1 II I I I 1 1 I I 1 I I 1 I 1 I I
CD

VJroEN! . EL 11 .0

EL 29.0

EL _ 11.0

Figure 10 .9 . Lock and Dam 1, Red River Navigation Project,

as constructed

(Corps of Engineers) .

SCALE

27 •	art

Figure 10 .10 . Areas cleared of sediment with submersible pump,

typical lock, Red River Navigation Project

(Neilans, et al ., 1993).

10- 1 5

Miter Gate

FLOW

Recesses

6 n ~.ns Ct..r .a
Spud

Spud

49111,

-,

(a) Dipper dredge

(b) Bucket dredge

Figure 10 .11 . Types of mechanical dredges

(U.S. Army, Corps of Engineers, 1983) .

Figure 10 .12. Self-propelled seagoing hopper dredge

(U.S. Army, Corps of Engineers, 1983) .

10- 1 6

Bucket

'/<

\t

//
V

m

ro

C

Spud

c. Types of cutterheads.

a. Hydraulic pipeline cutterhead dredge .

b. Cutterhead dredge 32, Bauer Dredging Co ., with ladder submerged .

Up

Spuds

Down

d. Operation of a cutterhead dredge

viewed from above.

Figure 10.13. Cutterhead dredges (U .S. Army Corps of Engineers) .

10-17
U.

v

v

0

a
C

CD

0

11.INNOVATIVE LOCK DESIGN

Settlement and development of the interior of the United States was initially by way 

the Ohio and Mississippi River, and the earliest navigation developments were on those rivers 

The first Federal public works program was clearing and snagging for navigation on the Ohi

River in 1842, and the first navigation lock and dam was constructed on the Ohio River, abou

five miles below Pittsburgh, in 1885 . It was very successful and led to construction of othe

navigation works on the Upper Mississippi, Ohio, and tributaries, Figure 11 .1 .

By 1929, 981 miles of the Ohio River had been canalized by 52 locks and dams t

provide a 9-ft channel . Later the original 52 structures were replaced with 20 higher lift locks

and non-navigable dams, Figure 11 .2 . Also there are 51 locks and dams on Ohio Rive

tributaries . Total length of the Ohio system is 2776 miles . The standard tow has 15 barges (3

wide, 5 long) and a towboat.

By 1940, 850 miles of the Upper Mississippi River had been canalized by 26 locks (110-

by 600-ft) and dams . Later larger locks were constructed at some locations ; a lateral canal wit

two locks was constructed near St. Louis; and navigation was extended 4 .6 miles upstream a

Minneapolis by construction of two smaller locks at St. Anthony Falls. The system now has 2

locks, Figure 11 .3 . The Upper Mississippi and tributaries now provide 1982 miles of navigabl

waterway. The standard tow is the same as on the Ohio River .

11.1 Need for Rehabilitation or Replacement of Navigation Structures

Annual waterborne tonnage on the Ohio River increased from 22 million tons in 1930 to

151 million tons in 1982 . On the Upper Mississippi, tonnage increased from 3 .1 million tons i

1940 to 91 million tons in 1982, Figure 11 .4.

Advances in towing equipment over the years, including towboats with increased engine

horsepower, have allowed larger and heavier tows to be moved and have extended navigation to

periods of relatively high flows and moderate ice conditions .

Modem tows are larger than the tows for which the locks and lock approaches were

designed. This, combined with higher entrance velocities at the locks during high flows, has

created navigation problems at the older locks. The longer tows require double lockage, and

operators must use extreme care in entering the locks. For example, lockage at the small old

Gallipolis Locks on the Ohio River required multiple lockages and as much as 4.5 hours to loc

through a single tow, while tows pass through the 1200-ft locks on the Ohio in about an hour 

Such delays are costly for shippers. In 1992 delays of tows at five of the locks and dams on the

Upper Mississippi totaled 87,000 hours, representing an estimated loss to shippers of $35 million 

When navigation projects on the Ohio and Upper Mississippi Rivers were designed and

constructed, projections of future traffic were much lower than what has actually occurred . Thus,

the locks have been more heavily used than foreseen, and expensive and frequent maintenance

has been needed. However, budget constraints have limited maintenance work, and many of the

older structures have deteriorated .
There is need for a systematic, effective, and adequately funded maintenance program for

waterway systems to remain useful and efficient . While routine maintenance is generally all that

is required in the early years of project operation, unforeseen construction may. be needed later

to enhance operation or correct deficiencies . It is important to perform maintenance as needed,

before problems become major and require closure of the waterway for major repairs .

Traffic from both the Upper Mississippi River and the Illinois Waterway passed through

the old Lock and Dam 26, on the Upper Mississippi at Alton, The old lock was both inadequate

to handle the size and number of tows on the river in the early 1980s and had serious structural

problems . The old 110- by 600-ft lock had an estimated maximum lockage capacity of 73

million tons per year. In 1981, 70.3 million tons passed through the old lock (total value o

cargo was $14 billion) . In 1982, a recession year, 68 million tons passed through, with an

average delay of tows of 10 hours due to backup of traffic .

Structural problems at Lock and Dam 26 (Niemi, 1986) included lateral and vertical

movement of both the lock and dam which were supported on vertically driven timber and

concrete piles. The stilling basin floor (3 .5 ft thick) had eroded as much as 2 to 3 ft, and voids

were found in the foundation alluvium under the dam and lock guide walls . Major emergency

rehabilitation work was undertaken in 1970 and 1971, and other repairs were made annually in

later years. Studies indicated it would be less costly to construct a new facility that to rehabilitate

the existing structures, and Melvin Price Locks and Dam were recently completed to replace Lock

and Dam 26.

The Melvin Price Locks and Dam project is located 2 miles downstream from the old

Lock and Dam 26 and includes one 1200-ft and one 600-ft lock . The dam has nine tainter gates

(100-ft wide by 42 ft high) and an overflow dike on the west bank . Two of the gate bays are

located between the locks . All spillway gates are operated at uniform opening. The 350-ft

separation between the locks allows simultaneous approach and departure of tows . Total project

cost was in the order of $974 million . Capacity of the new 1200-ft lock is estimated to be 94

to 100 million tons per year ; capacity of both locks is estimated to be about 179 million tons per

year and is expected to meet needs for the next 50 years .

11.2 Increasing Lock Capacity

Traffic capacity of locks can be increased somewhat by such measures as :

a.

Improving the hydraulic system or modifying the emptying system .

b. Improving lock approaches by widening or realignment, and improving the upper

approach by installing submerged dikes .

c. Instituting regulations for locking order to shorten lockage time . That is, passing

a specified number of tows in one direction, then passing tows in the other direction, rather than

locking tows through in order of arrival .

d.

Establishing hours for locking recreational boats, or constructing a recreation boat

lock.

e.

Using helper boats to move unpowered barges .

f. Requiring that large tows have bow thrusters .

11-2
c

Major increase in lock capacity can be realized only by providing additional lock chambe

space which can be done by:

a.Lengthening existing locks.

b. Replacing existing locks with larger locks .

c. Constructing additional locks.

11.3 Need for Innovations in Lock Design

The need for additional or replacement locks at many Corps projects becomes mor

critical each year, and construction costs have escalated dramatically, partly because replacemen

locks are larger than the structures being replaced . The cost of a 600-ft lock and dam on th

Arkansas River in the 1960s was in the order of $10 million . A similar lock and dam on the Re

River, completed in December 1994, cost about $115 million .

Total cost of the recently completed Melvin Price Locks and Dam on the Mississippi was

about $970 million, but that project included one 1200- and one 600-ft lock and more spillway

capacity than on the Arkansas or Red Rivers . Estimated cost of the Olmsted project now unde

construction on the lower Ohio River, which includes two 1200-ft locks, is in the order of $1 .

billion.

Navigation projects in the United States formerly were Federally funded . However, th

Waterways Development Act of 1986 requires that funding for new locks and for major

rehabilitation work be shared 50-50 by the Federal government and the Inland Waterways Trust

Fund. The Trust Fund derives its monies from a tax on fuel used on the inland waterway

system, currently 20 cents per gallon, and such revenues are limited . This restricts the number

of replacement and rehabilitation projects that can be undertaken each year, and the backlog o

critically needed work increases each year. Accordingly, the Corps of Engineers for the past few

years has vigorously pursued a program seeking innovative and less costly designs to restore the

aging navigation infrastructure .

11.4 Innovative Lock Design Program

The primary focus of the Corps' innovative lock design effort involves replacin

conventional gravity lock chamber walls with less costly thin walls between the miter gate

monoliths . At existing locks, filling and emptying culverts are located in the lock walls for all

the commonly-used filling and emptying systems. The new thin-wall concept would locate th

filling and emptying culverts on the floor of the lock chamber, and the intake systems could be

placed in the upper miter gate sill, Figure 11 .5 . Vertically mounted butterfly valves are proposed

for use as culvert control valves .

Because these new concepts are very different from conventional designs, the Corps has

undertaken a series of model studies to investigate hydraulic performance of the new filling and

emptying systems to ensure they will perform acceptably.

A model testing program has been set up at the USACE Waterways Experiment Statio

11-3
Winfield Locks and Dam, Kanawha River. Some of the innovative design concepts are

included in new twin 110- by 800-ft locks now under construction at Winfield, on the Kanawha

River. The old twin locks at Winfield are the busiest locks on the inland waterways system, with

over 20,000 lockages per year . The existing locks are 56- by 360-ft and can accommodate only

one modern jumbo barge of the type used to transport coal in the region . Typical coal tows are

composed of five barges that must be locked through one at a time at Winfield, requiring about

3 .5 hours for a single tow to pass through. Under adverse conditions, as long as five hours is

required, and tows often wait 24 hours before being locked through . These delays represent a

loss to shippers of about $17 million annually . The new 800-ft locks will be capable of passing

a 9-barge tow in a single lockage .

The upstream guide wall along the shore will have wide-flange steel piles grouted into

rock, with a reinforced concrete cap and skirt, instead of a continuous sheetpile wall . The length

of the wall will be 1000 ft, about half the usual length, and the remaining length will have the

bank sloped back and riprapped .

The upstream guard wall will have half as many concrete-filled sheet pile cells as

normally used, doubling the opening between cells to about 105 ft. There will be no pile arcs

between the cells, and post-tensioned cap beams will be used, rather than reinforced concrete .

These modifications of the upstream approach walls are estimated to have reduced the cost

of that work by more than one-third, or by about $5 million .

The first stage contract for construction of the cofferdam was completed in 1991 . The

contract for construction of the new lock and a 100-ft wide spillway bay between the old and

new locks was awarded in May 1994 . Pouring concrete began in April, 1995, and the lock is

scheduled to begin operation in spring, 1997 .

Modelini proiram. The modeling program currently underway at WES is set up in two

phases to make the best use of available time, facilities, and manpower. Phase 1 testing began

11-4
4

C

C

in March 1995. Model components and a lock facility needed for Phase 2 testing were compl

in late 1995, and testing has been initiated .

Phase 1 involves testing intake models to investigate site-specific intake 

approach conditions since this is likely to be one of the most difficult design features of the 

filling and emptying design.

outlets.

Phase 2 involves testing the proposed filling and emptying designs and the 

Intake models for McAlpine, Marmet, and Monongahela No . 4 Locks will be use

identify any undesirable flow patterns in the approach areas to the locks, such as strong vort

or concentrated flows, and to refine the intake designs if improvements are needed . Int

located in the miter gate sill are particularly susceptible to these types of flow conditions 

addition, the performance of the proposed intake and trashrack will be investigated, and veloci

in the intake area will be measured to help evaluate effects on tows in the area .

Testing of two filling and emptying models began in the summer of 1995 . The f

model was used to develop a filling and emptying system for McAlpine, Marmet, 

Monongahela No . 4 since proposed designs and project features are similar for these three loc

The second filling and emptying model will be for the Upper Mississippi lock . Model tes

of the filling and emptying systems will include determining optimum location of culvert p

and the need for baffles to deflect jets from the ports and reduce hawser stresses; evaluating 

distribution in the lock chamber with free tow drift patterns, measurement of longitudinal 

transverse hawser forces, and observation of surface currents . Different valve operations 

associated filling and emptying times will be tested, and average pressure measurements will 

obtained throughout the system . Performance of the lock outlets will be studied .

Tests initiated on the McAlpine intake model in March 1995 are complete . Prelimin

results indicate that it may be desirable to use extensions on ports in the laterals to better di

jets issuing from the ports perpendicularly to the culverts ; to use baffles along the walls 

centerline of the lock to redirect the jets and reduce hawser stresses ; and to relocate the int

ports from the miter gate sill to the approach walls (with externally mounted butterfly valves) 

reduce vortex problems.

Testing of the Marmet intake model and the McAlpine filling and emptying system 

scheduled to be completed in late 1995 .

Marmet Lock and Dam, Kanawha River. Marmet Lock and Dam is next upstr

from the Winfield project . The same upstream approach wall modifications adopted for Winfi

will be used at Marmet . In addition, the new filling and emptying system concept with culve

on the lock floor is expected to result in significant savings . It is also proposed to elimin

traditional vertical lift gates for emergency closure and the low-sill passage for use by emerge

craft if the upper pool is lost . This will permit the upper gate sill to be raised about 28 

reducing cost of the miter gates and the cost of dredging in the upstream lock approach .

11-5
It is estimated that the new Marmet Lock would cost in the order of $243 million if

traditional design criteria are used . It is expected this cost can be reduced by about $50 million

(20 percent) if innovative design concepts are adopted .

11-5 Other Innovative Concepts

Schmidgall (1995) has suggested two other areas were innovative design could enhance

lock operation

a. Model tests and prototype operation of locks with elaborate bottom longitudinal

filling and emptying systems have shown such locks can be operated satisfactorily with valve

opening times of one minute. Schmidgall suggests that lock filling time could be shortened and

the low pressure problems downstream of the filling valve at high-lift locks could be minimized

if the valve opening time were reduced to 15 or 10 seconds. With such a fast operating speed,

the valves would quickly pass through the partial gate opening settings that create negative

pressures before flow momentum has stabilized sufficiently to cause the low pressure problems 

b. An improved tow haulage system could significantly shorten the time required for

double lockages. Most systems now in use were not installed at the time the locks were

constructed, but were added later. These systems, which are typically cable, pulley, and winch

systems are located on top of lock walls and interfere with miter gate operation . Double lockage

times could be significantly reduced if the unpowered half of a tow could be pulled out of the

lock chamber and secured beyond the lock long enough for the powered half to lock through and

reattach to the unpowered half.
C

0

SL Paul, MN

Giro,! I SLLouis, :AO

•ECtr e

-

4

BMW

I h

l

I0

Alton, 1Li

l

v

New Orfuns, LA

Figure 11 .1, Upper Mississippi and Ohio River Navigation Systems

and Connecting Waterways

(Corps of Engineers).

POOL ELEVATION

FEET (METERS) ABOVE SEA LEVEL

DISTANCE ABOVE MOUTH OF OHIO RIVER

Pittsburgh, PA

owu u

Fairmont, WV-~ ,.• 4 NAW Wr

r'

.r

L.

Figure 11 .2, Profile of Ohio River Navigation Pools

(Corps of Engineers).

11-7

MILE 974 .8

I (1.569 Km (

MILE 967.7

(1,557 Km I

MILE 9493

(1,528 Km(
SST. ANTHONY-UPPER EL . 799 .2 (243 .6)

ST. ANTHONY •LOWER

6~•N

DAM 5

POOL ELEVATION

‚a e <

DAM 6

FEET (METERS) ABOVE SEA LEVEL

O ‚ Q~ ri m o

O Q

-, ~Lo

O Q r

~,_ ‚ ‚ a z--~ co

‚o aO

O Q g

O

•

-9,

-11

44

MILE 202 .9

(326 .5 Km)- 1

MILE 853 .9

(1 .374 Km)

DISTANCE ABOVE MOUTH OF OHIO RIVER

rn

QN -.,

O N N

Cam N O Q

CIO

l'1

‚

a

N

O

W

Q ~N

O

Figure 11 .3, Profile of Upper Mississippi Navigation Pools

(Corps of Engineers) .

175

150

a,

z 125

O

I--

L~ 100

O

z 75

0

50

25

OHIO RIVER

rr,

, rr

Ile

,r~~ UPPER

oe

000

MISSISSIPPI

RIVER

..r

t	.i---

.	

I	I	t	I	t	I

Figure 11 .4, Growth of Waterborne Commerce,

Ohio and Upper Mississippi Rivers

1930-1982 .

(Corps of Engineers)

11-8

0,

19301940 1950 1960 1970 1982
l

62ft

Figure 11 .5, Intakes in Upper Miter Gate Sill .

14-- 47 ft

551t

a

. Castin-plads

- .cap and ldcli

Raller=

compacted

w•-48(t 6in . -+~

Figure-11 .6, Lock Wall Monoliths with

Culverts in Lock Wall

and on Floor of Lock Chamber.

11-9
C?

C

APPENDIX A. REFERENCES

Ables, J. H., Jr ., Filling and Emptying System for Bay Springs Lock, Tennessee-Tombig

Waterway, Mississippi, U .S . Army, Corps of Engineers, Waterways Experiment Stati

Technical Report H-78-19, 1978 .

Ables, J. H., Jr., and M . B. Boyd, Filling and Emptying System, Dardanelle Lock, Arkan

River, U.S . Army, Corps of Engineers, Waterways Experiment Station, Technical Rep

H-69-5, 1969.

Antle, L. G. and D. V. Grier, Prioritizing Inland Waterway Infrastructure Needs, in Bulletin 

87, Permanent International Association of Navigation Congresses, 19

Cooper, D . R., Submersible-type Tainter Gate for Spillway, Marseilles Lock and Dam, U 

Army, Corps of Engineers, Waterways Experiment Station, Technical Report HL-89

1989.

Combs, P., and W. H. Espey, Jr., Sediment Management Challenges of the Red River Waterw

Project, ASCE Proceedings of the National Conference on Hydraulic Engineering, H

Chang and J. C. Hill, eds ., 1990.

Copeland, R. R ., and W . A. Thomas, Red River Waterway Sedimentation Study Downstream f

Lock and Dam 1, U .S . Army, Corps of Engineers, Technical Report HL-88-15, 1988 

Davidson, R. A., Gallipolis Lock Intake Vortex Study, Ohio River, U .S . Army, Corps 

Engineers, Technical Report 87-17, 1987 .

Davis, J. P., Hydraulic Design of Navigation Locks, U .S . Army, Corps of Engineers, Waterw

Experiment Station, Miscellaneous Paper HL-89-5, 1989 .

Derrick, D . L., Shallow-Draft Training Structure Current Repair Practices and Repair Guideline

U.S . Army, Corps of Engineers, Waterways Experiment Station, Technical Report REM

HY-8, 1991.

Elder, R. A., J. T. Price, and W . W. Engle, Navigation Locks : TVA's Multiport Lock Filling 

Emptying System, ASCE Journal of the Waterways and Harbors Division, February, 19

Franco, J. J., Development of Navigation with Locks and Dams . U.S. Army, Corps of Engineer

Waterways Experiment Station, Miscellaneous Paper H-76-15, 1976 .

Franco, J. J ., and J. E. Glover, Navigation Conditions at Robert S. Kerr Lock and Dam, Arkan

River, Waterways Experiment Station, Technical Report H-68-5, 1968 .

Franco, J. J ., and C. D. McKeller, Jr ., Navigation Conditions at Ozark Lock and Dam, Arkans

River, U.S. Army Corps of Engineers, Waterways Experiment Station, Technical Rep

H-68-10.

Grace, J . L ., Jr., Spillway for Typical Low-Head Navigation Dam, Arkansas River, Arkansas, U 

Army, Corps of Engineers, Waterways Experiment Station, Technical Report 2-655, 19

Huval, C. J ., Lock Approach Canal Surge and Tow Squat at Lock and Dam 17, Arkansas Riv

Project, U .S . Army, Corps of Engineers, Waterways Experiment Station, Technical Repo

HL-80--17 .

Little, C . D ., Jr., Numerical Model Analysis of Sedimentation Problems at Lock and Dam 1, R

River Waterway, ASCE Proceedings of the National Conference on Hydraul

Engineering, R. M. Ragan, ed., 1987.

Maynord, S . T., Safe Navigation Speeds and Clearance at Lower Sill, Temporary Lock 52, Oh

River, U.S . Army, Corps of Engineers, Waterways Experiment Station, Technical Repo

87-3, 1987.

A-1
Murphy, T. E., Lock Design, Sidewall Port Filling and Emptying System . U.S. Army, Corps of

Engineers, Waterways Experiment Station, Miscellaneous Paper 4-75-7, 1975 .

Murphy, T. E., Lock Design, Bottom Longitudinal Filling and Emptying System . U.S . Army,

Corps of Engineers, Waterways Experiment Station, Miscellaneous Paper HL-80-5, 1980 .

Neilans, P ., J . Clausner, J . Coldiron, and C . Corkern, Maintenance applications of a submersible

pump on the Red River Waterway, in U .S. Army, Corps of Engineers . Waterwaus

Experiment Station, Dredging Research, Vol DRP 93-2, May, 1993 .

Nelson, M. E., and H . J. Johnson, Navigation Locks: Filling and Emptying Systems for Locks,

ASCE Journal of the Waterways and Harbors Division, February 1964.

Niemi, J . R ., Aging Navigation Structures on the Mississippi and Ohio River Navigation Systems,

8th Annual USCOLD Lecture Series, Navigation Locks and Dams, New and Old, 1986 .

Petersen, M . S ., River Engineering, Prentice Hall, 1986 .

Petersen, M . S., and E . M. Laursen, Evaluation of Arkansas River Design Criteria for

Stabilization and Rectification of the Channel, Contract No . DACW39-86-C-0027 U.S .

Army, Corps of Engineers, Waterways Experiment Station, 1986 .

Pinkard, C . F ., Red River Waterway : A Sedimentation Challenge, ASCE Proceedings on the First

International Conference on Water Resources Engineering, W. H. Espey, Jr. and P. G.

Combs, eds ., 1995a.

Pinkard, C. F., Red River Waterway Project : General Design, ASCE Proceedings of the Firs t

International Conference on Water Resources Engineering, W . H. Espey, Jr. and P. G.

Combs, eds ., 1995b .

Robertson, R.R., Jr ., Locks and Dams - Red River Waterway, ASCE Proceedings of the Firs t

International Conference on Water Resources Engineering, W . H. Espey, Jr. and P. G.

Combs, eds ., 1995.

Schmidgall, T., Maintenance Dredging on the Arkansas River, in Sedimentation, H. W. Shen, ed.,

1972.

Schmidgall, T., McClellan-Kerr Arkansas River Navigation System, An Engineering Evaluation,

1 June 1981 (unpublished) .

Schmidgall, T., Twenty-six Years of Dredging on the Arkansas River, 14 December 1995

(unpublished) .

Shows, L. L., and J . J. Franco, Navigation Conditions at John H. Overton Lock and Dam, Red

River, U.S. Army, Corps of Engineers, Waterways Experiment Stations, Technical Report

HL 79-3,1979

Stockstill, R . L ., Olmsted Lock Outlet, Ohio River, U.S . Army, Corps of Engineers, Waterways

Experiment Station Technical Report HL 92-13, 1992 .

Tate, C. H., Jr ., Bay Springs Canal Surge Study, Tennessee-Tombigbee Waterway, Mississippi

and Alabama, U .S . Army, Corps of Engineers, Technical Report H-78-9, 1978.

U.S . Army, Corps of Engineers, Engineer Manual 1110-2-2606, Navigation Dams, 1952.

U.S . Army, Corps of Engineers, Engineer Manual 1110-2-1604, Hydraulic Design, Navigation

Locks, 1956.

U.S . Army, Corps of Engineers, Waterways Experiment Station, Dardanelle Lock and Dam,

Arkansas River, Technical Report 2-558, 1960.

U.S. Army, Corps of Engineers, Engineer Manual 1110-2-1611, Layout and Design of Shallow

Draft Waterways, 1980.

U.S. Army, Corps of Engineers, Engineer Manual 110-2-5025, Dredging and Dredged Material

Disposal, 1983.

A-2
C

U.S . Army, Corps of Engineers, Engineer Manual 110-2-1605, Hydraulic Design of Navig

Danis, 1987 .

A-3
C

APPENDIX B. RED RIVER WATERWAY. LOUISIANA

B.1 Project Description

The Red River Waterway was authorized by the U.S . Congress in 1968 with the primary

purpose of providing a 9-ft deep by 200-ft wide navigation channel from the Mississippi River

upstream to Shreveport, Louisiana, Figure B .1 . The project includes five locks and dams, with

a total lift of 141 ft . Construction of the project proceded in an upstream direction . Lock and

Dam 1 was completed in the fall of 1984 ; Lock and Dam 2 in the fall of 1987 ; Lock and Dam

3 in December, 1991 ; Locks and Dams 4 and 5 in December, 1994 . The project includes channel

realignment and bank stabilization . Total project cost was approximately $1 .8 billion, with about

half that cost being for the five locks and dams .

Preproject river length was about 280 miles, and this was shortened about 50 miles, or

18 percent, by realignment work . Shortening has lowered flood profiles . During the May, 1990,

high water on the Red River, a flood exceeding the 100-yr frequency event, peak stages at

Shreveport were in the order of one to two ft below what would have occurred prior to

realignment of the channel (Pinkard, 1995b) .

All dam spillways have tainter gates 60-ft long for normal operation to maintain the pool

during low-water periods and to pass flood flows . Lock and Dam 1 was designed to pass the

design flood (the 100-yr recurrence frequency event) with one ft of swellhead, but 11 gate bays

were required. Dams 2 through 5 have tainter gates and an uncontrolled ogee bay with crest set

at 2 ft above upper pool level and crest lengths ranging from 150 to 315 ft . For Dams 2 through

5, economic analysis of the costs of additional gates vs the costs of fewer gates plus the costs of

flowage easements for inundating additional lands indicated that it would be cheaper to use five

or six tainter gate bays and an uncontrolled crest, and obtain additional flowage easements rather

than to provide a larger number of tainter gates to pass the design flood with one foot of

swellhead, as discussed below .

Stilling basins were designed to provide submergence of 85 percent of the conjugate depth

of the entering flow and consist of a concrete slab with two rows of baffle blocks and a sloping

end sill (Robertson, 1995) . ,

All locks are 84 ft wide by 800 ft long and have sidewall port filling and emptying

systems designed to limit hawser forces to less than 5 ton . Locks are sized for a design tow

consisting of six barges (each 35 ft by 195 ft) and a tug . Lock lifts range from 35 ft to 24 ft,

and 6-barge tows can pass through a lock in a single lockage in about 25 minutes.

On the Red River, channel velocities become too high for commercial navigation when

flow is greater than the 10-year frequency flood (125,000 and 145,000 cfs at Shreveport and

Alexandria, respectively) . Therefore the top of lock chamber walls was set at an elevation of at

least 2 ft above the 10-yr flow line (in the order of 8 ft above normal lower pool level) so that

the locks are operational up to the 10-year flow frequency event. During high water, mean

channel velocities are about 7 ft/sec and maximum velocities are in excess of 10 ft/sec .

B-1
Each approach at Lock 1 has a floating guide wall 685 ft long to assist tows entering an

leaving the lock . When the I-wall at the lower lock approach at Lock and Dam 1 was overtopped

in the 1984-85 high-water period, shortly after the project became operational, there was major

sediment deposition in the vicinity of the lock . Material deposited against the lower miter gates

and fell into the lock chamber when the gates were opened . Studies indicated the downstrea

I-wall should be raised to a higher elevation, and the wall was raised vertically using treated

timbers supported by steel H beams . The timber wall extends 900 ft downstream of the miter

gates and has successfully reduced the deposition that occurs in the lower approach . Some

deposition still occurs, but in smaller amounts, and in areas that can be dredged more easily .

The pool at Lock and Dam 1 is at elevation 40 ; the dam has 11 tainter gates, and the loc

is separated from the dam by an 250-ft nonoverflow section . The upstream and downstream loc

approaches at Lock and Dam 1 are separated from the active flow portion of the river up to a

specific stage by an earthen embankment and a concrete I-wall, Figures 10 .9 and B.2 .

The navigation pool at Lock and Dam 2 is at elevation 64 ; the dam has five tainter gate

and a 190-ft uncontrolled crest at elevation 66 . This structure was under construction when initial

sediment problems occurred at Lock and Dam 1 in 1985, limiting modifications that could be

made to Lock and Dam 2 to avoid similar problems . To separate the downstream lock approach

from the main river flow, a rock dike was used the same length as the lock wall and at an

elevation 10 ft above the lower pool. This configuration was designed to provide a slack-water

area for the lower approach and allow some flow near the surface to enter the approach to lessen

eddy action. After Lock and Dam 2 went into operation in 1987, navigation conditions in the

upper lock approach proved to be difficult, as discussed in Section 9 .2 .

The navigation pool at Lock and Dam 3 is at elevation 95 ; the dam has six tainter gates

and an uncontrolled weir 315 ft long with crest at elevation 97 . The downstream guide wall is

on the riverward side of the approach to separate the lower lock approach from the main river

channel. Deposition downstream of the miter gate was still a concern, and 3-in drain pipes were

installed on 3-ft centers through the lower miter gate sill to provide almost continuous flow to

prevent deposition immediately downstream of the gates . This design appeared to be effective

and was incorporated in Locks 4 and 5 also (Robertson, 1995) .

Locks and Dams 4 and 5 have pool elevations of 120 and 145 ft, respectively . Thes

dams have five tainter gates, a hinged crest gate 100-ft long, and an uncontrolled weir 150-ft long

with crest 2 ft above normal pool level . The lower guide wall is on the river side of the

approach at both locks .

B.2 Sediment

The Red River drainage basin is approximately 96,000 sq miles, and about 50,000 sq

miles is above Denison Dam which traps most sediment from the upper basin. The primary

source of the sediment transported on the lower Red River is from bank erosion downstream fro

Denison Dam (Pinkard, 1995a) . The average annual suspended sediment load of the Red River

is 32 million tons at Shreveport (mile 228 .4) and 37 million tons at Alexandria (mile 88 .6) . Th

B-2
suspended load is roughly 25 percent fine and very fine sand and 75 percent silt . Bed load 

estimated to be less than 10 percent of the total load . Bed material is predominately fine 

medium sand, and the material becomes finer in a downstream direction .

Significant sediment deposition problems developed at Lock and Dam 1 in the high-wa

period following completion of the project in the fall of 1984 : in the upstream lock approa

along the riverside lock wall ; in the downstream lock approach channel ; and in the lock chamb

as shown in Figure B .2 .

Deposition in the upstream approach, which was a slack-water area, occurred when fl

exceeded 60,000 to 70,000 cfs (the 1-yr frequency flood is 95,000 cfs), appeared to be rela

to the width needed for safe navigation by tows entering and leaving the upper channel entra

and also by concentration of flow in a deep natural channel along the right bank . A series 

four spur dikes was constructed along the upper right bank, Figure B .3, to direct flow toward 

left bank. Following construction of the dikes, maintenance dredging in the upper approa

decreased significantly, from 1,024,000 cu yds in 1984-85, to 284,000 in 1985-86, and 242,0

in 1986-87. Hydrographs for the three years were comparable (Little, 1987) .

Deposition in the lower approach occurred when the tailwater overtopped the downstre

I-wall, resulting in eddy action in the lower approach . The I-wall is overtopped for long peri

due to backwater from the Mississippi River . Material deposited was primarily very fine sa

and silts, with a d50 of 0.07 mm. In the downstream approach, there was as much as 20 ft 

deposition adjacent to the lower guide wall and 8 to 10 ft around the lower miter gate followi

the 1984-85 high water, Figure B .2 . There was concern that deposition along the riverside l

wall would threaten stability of the wall, and sediment deposition resulted in damage to the lo

miter gates. Repairs closed the river to navigation for about three months in 1985 .

The elevation of the downstream I-wall (38 ft) was raised by constructing a timber wa

with top elevation of 55 extending 900 ft downstream from the miter gates . After th

modifications were made, deposition downstream of the lock decreased substantially, Figure B 

A profile showing typical deposition in the lower approach in 1985, prior to construction of t

timber wall, is compared with deposition in 1987 with the timber wall in place in Figure B 

While deposition was not completely eliminated in the lower approach by these measures, it 

moved downstream to where it is not a threat to the structure and can be easily removed .

Maintenance dredging at Lock and Dam 1 is discussed in Section 10 .4 .

B.3 Hinged Pool Operation

Hinged pool operation can be used for sediment management as well as to reduce r

estate acquisition costs. As flood levels drop, water surface slopes through a pool decrease, a

sediment tends to deposit in the middle reach of some pools . Drawing the pool down at the lo

and dam increases the water surface slope through the pool, providing better sediment transpo

Material tending to deposit in the head end of the pool is transported farther downstream into 

pool where depths available for navigation are greater .

B-3
Pool hinging to reduce maintenance dredging quantities has been tested in several pools

on the Arkansas River (Corps of Engineers, 1987) . Results indicated that a hinging operation has

the potential to substantially reduce dredging quantities in some pools, but that to maximize

benefits it is necessary to determine the optimum time to initiate .and terminate dredging for eac

pool.

Several design factors must be considered where hinged pool operation is planned :

a. The upper gate sill must be set sufficiently low so that navigable depth is provided

when the pool is lowered .

b. Velocities and cross currents in the upper lock approach may be more severe than with

normal pool operation .

c. Tie-up facilities for tows along the upper approach wall must be usable at the lowere

pool level .

d. Port and docking facilities, water intakes, and similar structures just upstream of the

dam must be designed to avoid problems resulting from lower pool levels .

e. Rapid pool drawndown may cause bank instability .

f. Operation of the spillway gates is more complex than for normal pool operation, an

this could lead to misoperation of the gates .

Locks and Dams 3, 4, and 5 on the Red River are designed for hinged pool operation, but

at this time only Lock and Dam 3 is operated as a "hinged pool ." A constant pool elevation o

95 ft is maintained during low flows, and as streamflow increases, the water surface at Lock an

Dam 3 is drawn down to 89 ft. The water surface at the dam is maintained at this lower level

until tailwater begins to control the pool level . Less land is inundated at the head end of the poo

with this operation than if the pool were held at normal pool level . Comparative water surfac

profiles and limits of acquisition of flowage easements with and without hinged-pool operatio

are shown on Figure B .5 .

B.4 Reaeration

Low dissolved oxygen levels below impoundments during summer low-flow periods ca

be very detrimental to fishery resources, and various measures are employed to alleviate the

problem. At Dams 4 and 5 on the Red River, a hinged crest gate is used at one spillway bay to

draw warm water from the surface of the pool and discharge it onto a baffled chute, Figure B .6 

Turbulence on the chute increases the dissolved oxygen concentration .

B.5 Optimization of spillway design

Lock and Dam 1 was designed to pass the project design flood (100-yr recurrenc

frequency post-project flood)_ with one ft of swellhead. A gated dam with 11 spillway bays wa

needed to meet this criterion, and the widened channel cross section required in the vicinity of

the lock and dam to accommodate the structures was a contributing factor to sediment deposition

problems immediately after the project went into operation .

B-4
C

B-5
LEGEND

Loex & Dam System

Figure B.1, Red River Waterway, Louisiana, plan and profile

(Combs and Espey, 1990) .

000

OF ALL

FLOW DAM

am.moms$

Figure B.2, Initial deposition problem areas

Lock and Dam 1, Red River Waterway.

(Little, 1987) .

O

0s 10 ,s 20

SCALE IN MILES
FLOW_,_

LOCX

i

T41811 II WALL

(EL. 55 f . .t, NOVO)

	I	 1

O

f0

a S

0

a.

W

Figure B.3, Bed elevations 20 days after dike construction

Lock and Dam 1, Red River Waterway

(Little, 1987) .

$-WALL (EL . 3S feet, NOM

	 • WITIAL OEPOS1TN)N (tSSS)

!s

MOTOTTPE

Figure B .4, Deposition below Lock and Dam 2 resulting from

hydrograph for period 19 November 1986 to 6 January 1987

(Little, 1987) .

O

O

i- = =J

i J F

t

t

C

OJ3 o

W JW

f - O WO C

OQ ZO

W

W

O

W
i LIMITS OF FLOWAGE EASEMENT W/O HINGED POOL

.

f

a

a

•~LlM/TS OF fLOWAGE EASEMENT

v

.WITH HINGED POOL

~~\ -?OrLP

LOCK ANO OAM N

9~E

ORDINARY OILHIGHWATEALINE\ ~\ T ~z OIyL,'NE

ACQUISITION

LINE

.M. 169+

NOTE: 0 - 100 .000 CFS FOR THIS ILLUSTRATION

Figure B .5, Hinged pool operation,

Lock and Dam 3, Red River Waterway

(Corps of Engineers, 1987) .

I .M. 117+
RIPRAP•

0•

a . Section through baffled spillway chute .

b. Details of hinged gate.

Figure B.6, Hinged gate and baffled spillway chute,

Locks and Dams 4 and 5, Red River Waterway

(Corps of Engineers).

B-9

	 FI.192.0

EL . 145.0 TOP OF G&TE

EL. 138.0

EL 134 0

EL. 161 .33

EL . 164.0

1

I

I FC

f

EL 140 5

I ~2

I

fnI

L_ .2-

L

hI

`\ i~

III

.-2& ~~_~-~

EL . 120.0 , A ,‚

.116.69

I 1

I

. EQUALIZATION

_t .u7.U PIPE - EL .113 .0

• EL .109.0

I

E!. :07.0 ---

CL 100 0

-SHEET PILE --- SHEET PILE

SHEET PILE

CUTOFF

CUTOFF CUTOFF

I

L5

1 .5'

53 .0'

28.0•

30.0 81.0
Attachment B .1 . Typical Spillwav Optimization Study, Red River. Louisiana

(Appendix D . CE EM 1110-2-1605,12 May, 1987)

1 . SCOPE . This appendix summarizes the optimization studies for selection o

spillway components . The goal is to select the optimum number of spillway

gates and length of overflow dam . The spillway alternatives studied are

tabulated in Table D-3 .

2 . DESIGN GUIDANCE FOR NAVIGATION DAM STRUCTURES .

a,. Plans with Gates Only (No Overflow Dam) . These plans provide a

T-wall dam extending from last gate pier to nonoverflow embankment dam.

Length of T-wall dam is governed by excavation slopes for last spillway gate

bay and by location of the riverward end of the nonoverflow embankment dam .

The landward end of the T-wall dam must be embedded in the riverward end of

the nonoverflow embankment dam . The tops of abutments and T-wall dams must be

above the headwater for the project design flood plus wave runup . Provide

minimum training wall downstream of last gate bay .

b . Overflow Dam Plans with Weir 300-, 600-, and 1 .200-foot Crest

Lengths . These plans provide concrete overflow dam from the last gate pier to

the overflow embankment dam . Length of concrete overflow dam is governed by

excavation slopes for last spillway gate bay and by the riverward end of the

overflow embankment dam. The overflow embankment dam was extended landward so

that total length of concrete overflow plus embankment overflow is 300, 600,

1,200 feet, or other selected lengths . Easy vertical transition from overflow

embankment to nonoverflow embankment has been provided . For some instances

with four, five, and six gate bays, stone will not resist the overflow

velocities on the downstream edge of the embankment crown, and a concrete

section must be provided . Minimum training wall downstream of last gate bay

must be provided .

c . Soillwav Gate Piers . The trunnion anchorage elevation can be the

same for all gate arrangements since it is related to tailwater .

d . Riorao . Riorap that is needed for each dam arrangement must be provided . A complete layout plan for each dam arrangement must be developed .

e . Too of Lock Walls . The top of lock walls will be eight feet above

the normal upper pool for all gate arrangements . This elevation will provide

substantially more than two-foot clearance above the headwater for a 10-year

flood for all gate arrangements .

f . Stilling Basins and Gated Weirs . The stilling basin will have the

same dimensions in an upstream-downstream direction regardless of the number

of gates . The gated crests will also have the same dimensions regardless of

the number of bays .

B-1 0
C

3 . FLOWAGE EASEMENTS,

a . Some of the spillways would raise flood heights above preproject e

vations . Assume that flowage easements are required on all lands above the

ordinary high-water line on which flood heights are increased .

b . The channel realignments on this waterway would reduce the overall

river length from the mouth of the Black River (1967 mile 34 .2) to Shrevepo

(1967 mile 278) by 48 miles . This shortening will cause a reduction in flo

elevations, and the reduction at the Lock and Dam 3 site is estimated to be

2 .2 feet . This postproject reduction of 2 .2 feet was taken into account wh

determining whether a given spillway arrangement would raise postproject fl

levels above preproject levels . For example, the six-gate, 315-foot-weir

spillway would cause a headwater elevation 2 .2 feet above postproject tailwater elevation for the project design flood (PDF) . However, this spillway

would not raise flood heights since the postproject tailwater elevation is

estimated to be 2 .2 feet below the preproject tailwater elevation .

c . Table D-2 shows how much various spillway arrangements would raise

the PDF (248,600 cfs) above preproject level at the damsite and the land

acreages on which the PDF would be raised . The calculations showed that the

following spillway arrangements would not raise the PDF above preproject

conditions .

Number of GatesLength of Overflow Dam . feet

4 1,510 and longer

5 935 and longer

6 315 and longer

7 0 and longer

8 0 and longer

d . It is proposed to acquire flowage easements up to elevation 98, whi

is three feet above the navigation pool elevation and one foot above the top

of the overflow dam. When a postproject discharge reaches this headwater el

vation at the damsite, the water-surface profile upstream will be higher tha

the flowage easement elevation 98 throughout Pool 3 . The postproject discharge will be 178,000 cfs when the headwater elevation at the damsite is 98

and this discharge has an average recurrence interval of about 33 years .

e . The preproject profile for 178,000 cfs was calculated and compared

with the postproject profiles for this discharge for the various spillway

arrangements . The postproject profiles for the six-, seven-, and eight-bay

spillways were equivalent to or lower than the preproject profile . Since th

178,000-cfs discharge would be only about a foot above the top of the overfl

dam, the length of overflow dam does not have a significant effect on the

headwater elevation . Table D-1 shows how much various spillway arrangements

would raise the 178,000-cfs discharge above preproject level at the damsite

and the land acreages on which this discharge would be raised .

4 . LEVEE RAISING . The following spillway arrangements would raise the PDF 

a foot or more above preproject and would require raising the flood-control

levees adjacent to Pool 3 to provide the preproject level of protection .

B-il
Number of Bays,

Length of Overflow Dam, feet

4

None

4

300

4 600

4 1,200

5 None

5 300

5 600

6 None

The entire length of this levee would be raised by the amount of height th

the postproject PDF is raised above preproject at the mouth of Saline Bayou 

The levees would be raised to the same height above the postproject PDF as

they were above the preproject PDF .

5 . COMPARATIVE COSTS . Detailed cost estimates were calculated for each of

the alternative spillway arrangements using October 1982 price levels . The

estimates are summarized in Table D-3 .

6 . CONCLUSIONS AND RECOMMENDATIONS .

a . The alternative consisting of a six-bay spillway and 315-foot

overflow dam is the least costly considering all costs and is the selected

spillway . The lock and dam structure costs for some of the alternatives we

less than for the selected plan, but their costs for additional flowage

easements and levee raising caused their total costs to be higher .

b . The recommendations for this site-specific study is to proceed wit

the alternative consisting of six-bay spillway and 315-foot overflow dam

design .

TASL'a D-1

Spillway Arrangements That Would Raise 178 .000 cfs Above Preoroject

Spillway5eignt of ?ostArrangement project 178,000 Flowage Flowage

cfs above Pre- Easements Basements

Length of project 178,000 Required on 3eeuired on

No . of Overflow cfs at Damsite Main Stem Tributaries

Says Dam, feet	feet acres	Aoorox . acres

4

All 2.0 7 .000 6,910

5 All 0 .9 7,000 6,910

B- 1 2
TABLE D-2

Spillway Arrangements That Would Raise the PDF Above Preoroject

Spillway

Arrangement	

Length of

No . ofOverflow

Says Dam . feet

4 None

4 300

4 600

4 1,200

5 None

5 300

5 600

6 None

6 300

	

Spillway

Alternative

Length

No . of of Overflow

9avsDam . feet

de .gnt of Flowage Flowage

Postproject Easements Easements

PDF above Pre- Required on Required on

project PDF at Main Stem Tributaries

Damsite . feet

acres Aoorox acre

in Dollars Rounced to Nearest Tenth of a Million

* Structure costs were extrapolated . This alternative would not raise the

PDF.

Structure costs were interpolated . This alternative would not raise the

PDF.

t This is the selected alternative . It would not raise the PDF . The sixbay spillway and 315-foot overflow dam was selected over the six-bay

spillway and 300-foot overflow dam because the latter alternative would

raise flood heights slightly above preproject conditions . No additional

costs were shown in the table for additional flowage easements and levee

raising for this slight rise in flood heights because they would be of

questionable accuracy . However, the 315-foot overflow dam has the

advantage of not raising flood heights, while the 300-foot overflow dam

could be difficult to defend since it will raise flood heights to some

extent .

B-13

4 0 152 .6 11 .6 24 .7 193 .9

4 300 154 .8 11 .4 12 .1 178 .3

4 600 156 .5 11 .3 8 .0 175 .3

4 1,200 158 .1 10 .4 Min 168 .5

4 1,510* 158 .9 10 .4 Min 169 .3

5 0 163 .8 11 .4 10 .8 186 .0

5 300 162 .0 10 .4 4 .9 177 .3

5 600 162 .4 10 .4 Min 172 .8

5 935"163 .3 10 .4 0 173 .7

5 1,200 164 .5 10 .4 0 174 .9

6 0 170 .0 4 .8 3 .4 178 .2

6 300 168 .0 0 0 168 .0

6 3157 168 .0 0 0 168 .0

6 600 168 .6 0 0 168 .6

6 1,200 170 .7 0 0 170 .7

7 0 176 .3 0 0 176 .3

7 300 174 .3 0 0 174 .3

7 600 175 .9 0 0 175 .9

7 1,200 179 .3 0 0 179 .3

8 0 183 .8 0 0 183 .8

8 300 182 .3 0 0 182 .3

8 600 183 .8 0 0 183 .8

8 1,200 187 .6 0 0 187 .6

5 .3 8,500 6,910

2 .8 8,241 6,910

2 .0 8,147 6,910

0 .6 7,000 6,910

2 .4 8,273 6,910

1 .2 7,000 6,910

0 .7 7,000 6,910

1 .0 3,328 3,075

0 .2 -

TABLE D-3

Comoarative Costs

Lock and DamAdditional Levee Total

Structure Flowage Raising Comparative

Costs Easement Cost Cost
INDEX

A

Air admission at culvert filling valves, 8-19, 9-8,

9-26

Arkansas River, 8-2 (see also Dardanelle Lock and

Dam; Robert S . Ken: Lock and Dam ;

Lock and Dam 17, Verdigris River)

additional contraction, 10-3

cofferdams, 8-32

construction sequence, 10-2, 10-3

cutoff, typical, 10-11

dikes, typical system, 10-10

dredging, 10-2

initial dredging, 10-3

maintenance dredging, 10-3, 10-4

annual volumes, 10-12

cumulative volume, 10-4

function of discharge, 10-14

policy, 10-4

Pool 2, 10-3, 10-4

hinged pool operation (see Hinged pool

operation)

locks, 8-22, 9-2

costs, 11-3

discharge manifolds with baffles, 8-51

navigation dams, 7-1

navigation project, 10-10, 10-11

project plan, 10-11

pool characteristics, 10-3, 10-4

sediment load, 10-2

spillway piers, 7-5

submerged dikes in upper lock approach, 9-2

Ell

Barkley Lock, 8-16

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 8-7, 8-23, 8-55, 9-6, 9-7,

9-8

canal surge, 9-7

construction, 8-34

I-1

downstream canal design, 9-7

emptying time, 9-7

filling time, 8-23, 8-24

floor culverts, 8-23

hawser stresses, 8-23, 9-7

intake design, 9-8, 9-25

layout, 9-21

lock emptying time, 8-23, 9-7

outlet system, 9-7

valve opening time, 9-7

vortex action, 9-8

Bottom longitudinal floor culverts (see Longitudi

floor culverts)

C

Canal surges, 9-4

amplitude

Bay Springs,Tennessee-Tombigbee

Waterway, 9-7

Verdigris River, 9-8

Canalization, 1-2, 3-1

Arkansas River, 10-2

Ohio River, 7-2, 11-1, 11-17

physical constraint, 2-1

planning, 2-1

economic studies, 2-1

evaluating existing streams, 2-1

locks, 2-2

navigation equipment 2-1

physical constraints, 2-1

tow size, 2-2

views of users, 2-2

Red River Waterway, B-1

Upper Mississippi River, 10-14, 11-1, 11-18

Channel width (see Navigation channel, width)

Choteau Lock and Dam (see Locks, Lock and D

17, Verdigris River)

Cofferdams, 8-2, 8-29, 8-30, 8-31, 8-32

Dardanelle Lock and Dam, Arkansas River,

8-2,8-32
Lock and Dam 26 replacement, Mississippi

River, 8-2, 8-31

passing navigation traffic, 8-2

problems during project construction, 8-2

Smithland Locks and Dam, Ohio River, 8-2,

8-30

stages of construction, 8-2

Construction

cofferdams, 8-2

off-channel (in the dry), 8-2, 8-33

Dardanelle Lock and Dam, Arkansas River, 8-2

materials availability, 8-3

Melvin Price Locks and Dam, Mississippi

River, 8-2

Red River Locks and Dams, 8-2, 8-33

site access, 8-3

Construction materials, 8-3

Corps of Engineers

Inland Waterways System, 1-1

innovative lock design, 11-3

Cross currents

effect on navigation, 8-1

Culverts (see Lock culverts, Lock filling and

emptying systems)

Currents

cross currents, 8-1, 9-2, 9-3

hazardous currents, 5-3

lower lock approach, 8-21

ports in lower guard wall, 9-2

ports in upper guard wall, 9-1, 9-2

upper approach, Dardanelle Lock, 9-2

Cutoffs

Arkansas River, 10-11

Red River Waterway, B-1

D

Dams

classifification by head, 3-1

low-head dams, 7-1

wickets, 7-7

Dardanelle Lock and Dam, Arkansas River, 8-2,

8-22,9-2

baffles, 8-22

cofferdams, 8-32

deposition in lower lock approach, 9-9

filling time, 8-22

hawser stresses, 8-22

intake ports, 8-44

longitudinal floor culverts, 8-53

ports in guard walls, 9-2

1-2

sediment, 10-2

submerged dikes in upstream lock approach,

9-2

trashracks, 8-44

wing dike in lower approach 9-9

Depth

minimum depth, 5-1

Dikes

Arkansas River, 10-10

Red River Waterway, B-3, B-7

submerged in upper lock approach, 9-2

Lock and Dam 2, Red River, 9-2

Arkansas River locks, 9-2

Discharge manifolds, 8-49, 8-50, 8-51 (see also

Lock emptying systems)

Disssolved oxygen levels, 7-2 (see also Reaeratio

Double lockage (see Lockage time, double lockag

Dredged material disposal

disposal areas, 10-9

problems, 10-9

Dredging, 10-1

advance maintenance dredging, 10-2

aperiodic dredging, 10-1

Arkansas River (see Arkansas River, dredging

at heads of pools, 4-4

costs, 10-1

environmental impacts, 10-1

initial construction dredging, 10-1

maintenance dredging, 10-1

effect of hinged pool operation, 10-7

effect of reservoir operation, 10-2

Mississippi River, 10-5

Missouri River, 10-6

objectives, 10-1

overdepth dredging, 10-1, 10-2

new construction dredging, 10-1

periodic dredging, 10-1

priorities, 10-1

production rate, 10-1

Red River, 10-6

selecting disposal method and site, 10-1

selecting dredging method, 10-1

Dredging equipment

discharge lines, 10-8

floating lines, 10-8

shore lines, 10-8

hydraulic pipeline (suction) dredges, 10-7,

10-8, 10-17, 10-18

cutterhead, 10-8, 10-18

dustpan, 10-8, 10-18

plain suction, 10-8

sidecasting, 10-8
V

hopper dredges, 10-8, 10-16

mechanical dredges, 10-7, 10-16

bucket dredges, 10-7

dipper dredges, 10-7

Drift angle of tow, 5-5

IF,

Eddies in lower lock approach, 9-4

Emergency lock closure (see Lock closure facilities)

Fish, migratory

mitigation measures, 6-2

Flood releases

tapering off, 10-2

rate - of flow reduction, 10-2

Flood stage

effect on dam height, 6-1

hinged-pool operation, 6-1

Flows limiting navigation, 9-1, B-1

Gallipolis Locks and Dam, Ohio River

innovative lock design, 11-1

intake manifold, 8-45, 8-46

vortex action, 8-18

Gates (see Spillway gates ; Lock gates)

Gate sills . (see Lock gates, gate sills)

Greenup Locks, Ohio River, 8-21, 9-1, 8-40

Hazards (see Navigation hazards)

Hawser forces, 8-13, 8-19, 8-20

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 9-7

Dardanelle Lock, 8-22

disturbances causing, 8-13

limiting criteria, 8-13

model data, 8-13

Head

reverse head, 8-6, 8-8

High-lift locks, 8-22

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 8-23

I-3

bottom longitudinal systems, 8-22

filling and emptying systems, 8-22

Lower Granite Lock, Snake River, 8-22

Hinged pool operation, 6-4, 10-2

Arkansas River, 1995 floods, 10-7

design factors, B-4

effect on maintenance dredging, 10-7

Red River Waterway, B-3, B-8

Locks and Dams 3, 4, and 5, B-8

Hinged spillway crest, 7-2, B-9

Hydropower at navigation dams, 6-3

flow available for generation, 6-3

I

Ice

accumulation on barges, 8-8

passing ice at navigation projects, 7-5

Upper Mississippi River, 7-5

Illinois River, 7-4

Inland waterways system in U.S ., 1-4, 11-7

Innovative lock design (see Locks, innovativ

design)

Intake manifolds (see Lock intake manifolds)

K

Kanawha River, 8-5, 11-4, 11-5

L

Lift (see Lock lift)

Lockage time

delays, 11-1, 11-4

double lockage, 11-1, 11-6

Lock approach conditions, 5-3, 9-2, 9-3, 9-4

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 9-7, 9-23

Dardanelle Lock, Arkansas River, 9-2, 9-

9-31

dikes

submerged, 9-2

contraction B-7

eddies in lower approach, 9-4

fill along shore line, 9-3

guide and guard walls, 5-3, 9-31

Lock and Dam 1, Red River Waterway, B

B-7
Lock and Dam 2, Red River Waterway, 9-2,

9-11, B-2, B-7

Lock and Dam 17, Verdigris River, 9-8, 9-27,

9-28, 9-29, 9-30

Lock and Dam 52, Ohio River, 9-4, 9-18

Olmsted Lock, Ohio River, 9-4, 9-16, 9-17

Red River Waterway, B-2, B-3, B-7

Robert S . Kerr Lock, Arkansas River, 9-3,

9-12, 9-13, 9-14, 9-15

sediment deposition (see Shoaling in lock

approaches)

shoaling (see Shoaling in lock approaches)

sight distance, 9-1

spur dikes, B-3, B-7

Lock capacity

increasing lock capacity, 11-2, 11-3

Lock and Dam 26, Mississippi River, 11-2

Melvin Price Locks and Dam, Mississippi

River, 11-2

Winfield Locks and Dam, Kanawha River, 11-4

Lock chamber size, 8-3

Lock closure facilities

emergency closure, 8-24, 8-25

facilities, 8-25

sills, 8-8

Marmet Lock, Kanawha River, 11-5

Ohio River locks, 8-25

overhead vertical lift gates, 8-25

potential losses, 8-24

sector gates, 8-25

submergible gates, 8-25

stop logs, 8-25

maintenance closure, 8-24

Arkansas River locks, 8-24

low-lift lock facilities, 8-24

submergible gates, 8-24

Lock culverts (see also Longitudinal floor culverts)

air entrainment, 8-19, 9-8

air vent size, 9-8

control valves, 8-18, 8-47

tainter gates, 8-18

valve opening times 8-19, 8-47

intakes, 8-18 (see also Lock intake manifolds)

surges, 9-8

wall culverts

bulkheads, 8-19

side-port systems, 8-19

unwatering, 8-19

Lock emptying systems, 8-21, 8-49, 8-50, 8-51,

8-52 (see also Lock filling and

emptying systems)

baffles, 8-22

1-4

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 9-22, 9-24

common river outlet for two locks, 8-22, 9-4

emptying in lower approach, 8-21, 8-49, 8-5

9-1

emptying riverward of locks, 8-21, 8-22, 8-4

8-52, 9-1

Greenup Lock, Ohio River, 8-49, 8-52

lateral diffuser systems, 8-49, 8-50

Greenup Locks, Ohio River, 8-21, 8-49

McArthur Lock, St . Mary's River, 8-21, 8-49

New Cumberland Locks, Ohio River, 8-21,

8-50

Olmsted Locks, Ohio River, 8-52, 9-4

Saint Anthony Falls Lower Lock, Mississipp

River, 8-21, 8-50

Snell Lock, St. Lawrence Seaway, 8-21, 8-4

Lock emptying time, 8-39, 9-7

Lock filling and emptying systems, 8-4, 8-5, 8-12

8-15 (see also Lock emptying syste

Locks, innovative lock design)

baffles, 8-51

incremental valve opening, 8-15

longitudinal floor culverts, (see Longitudinal

floor culverts)

loop culverts, 8-14

low-lift locks, 8-40

modem systems, 8-15 (see also Lock filling

and emptying systems, Longitudinal

floor culverts)

over, between, around lock gates, 8-14

sector gates, 8-14

tainter gates, 8-14

stub culverts, 8-14, 8-40

TVA multiport system, 8-20

valves in . gates, short culverts, 8-14

wall culverts and bottom lateral systems, 8-

8-40

wall culverts and ports or laterals , 8-15

early conventional systems, 8-15

wall culverts and port systems, 8-15, 8-19, 

port/culvert area ratio, 8-23

port design criteria, 8-19

port elevation, 8-19

port length, 8-19

Lock filling systems (see Lock filling and empty

systems)

Lock filling time, 8-41, 8-47

improved tow haulage system, 11-6

innovative design, 11-6

prototype-model relationship, 8-38
V

I

Lock floor, 8-6

uplift, 8-6

elevation criteria, 8-6

stabilization of foundation, 8-6

Lock gates, 8-6, 8-34

design load, 8-6

emergency closure, 8-8, 8-25

gate opening time, 5-4

gate sills, 8-6, 8-34

depth/draft ratio, 8-8

effect of ice on clearance, 8-8

sill clearance, 8-7

sill elevation, 8-7, 8-8

Temporary Lock 52, Ohio River, 9-4

lift gates, 8-8

miter gates, 8-6, 8-8, 8-35

operation, 8-6

sector gates, 8-8, 8-14, 8-37

submergible gates, 8-36

tainter gates, 8-8, 8-14

tidal channels,8-8

types, 8-6

Lock intake manifolds, 8-16, 8-17, 8-18

Bay Springs Lock, Tennesse-Tombigbee

Waterway, 8-42

bulkheads, 8-17

Dardanelle Lock, Arkansas River, 8-44

Gallipolis Locks, Ohio River, 8-45, 8-46

head loss coefficients, 8-43

Ice Harbor Lock, Snake River, 8-42

innovative design, 11-3

passing drift and ice, 8-16

port/culvert area ratio, 8-16

port size, 8-16

port throat area, 8-16

Saint Anthony Falls Lower Lock, Mississippi

River, 8-42

Siamese intakes, 8-16, 8-40

submergence, 8-17

trash racks, 8-17, 8-44

unwatering, 8-17

upper gate sill intakes, 8-16, 11-3, 11-5

vortex action, 8-17

Lock lift, 3-1, 8-4

high-lift locks, 3-1, 8-22

intermediate lift locks, 3-1, 8-4

low lift locks, 3-1, 8-4

Lock walls, 8-9, 8-34

approach walls, 8-11, 8-12

ports to reduce cross currents, 9-2

types, 8-12

culvert discharge walls, 8-11

I-5

culvert intake walls, 8-10

gate bay walls, 8-10, 8-11

guard walls, 5-3, 8-11, 9-2

ports, 9-2

guide walls, 5-3, 8-11, 9-3

flow distribution through ports, 9-3

Lock and Dam 1, Red River Waterway,

B-2, B-6

Lock and Dam 2, Red River Waterway,

9-2, 9-3, B-2, B-6

Lock and Dam 3, Red River Waterway,

B-2

ports, 9-3

Robert S. Kerr Lock, Arkansas River, 9

height, 8-5, 8-9, 8-10, B-1

Red River Waterway, B-1

lock chamber walls, 8-10

sight distance, 8-1

types, 8-4, 8-12

criteria, 8-4

walls categorized by purpose, 8-9

wall port systems, 8-16, 8-19 (see also Wall

ports)

port design criteria 8-19

port elevation 8-19

port length, 8-19

Locks

approach conditions (see Lock approach

conditions)

access during floods, 8-10

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 8-23, 8-55

Bankhead Lock, Black Warrior River, Alaba

8-54

classification by lift, 3-1

closure during floods, 8-9

combination type, 8-5

costs, 11-3, 11-6

cushion of water, 8-5, 8-19

Dardanelle Lock and Dam, Arkansas River,

8-22

depth, 8-5, 8-6

sill elevation, 8-6

tow squat, 8-7

design criteria, 8-3

lock size, 8-3

number of locks, 8-3

dimensions in United States, 8-3

double lockage 11-1, 11-6

Winfield Locks and Dam, Kanawha Rive

11-4

dry-dock type, 8-4, 8-5
filling criteria, 8-19

filling time, 8-5, 8-13

optimum filling time, 8-8

Greenup Locks, Ohio River, 8-21, 9-1

hazardous approach conditions, 9-1

innovative lock design

Corps of Engineers test program, 11-3

culverts on lock floor, 11-3

faster valve operating speed, 11-6

guide and guard walls, 11-4

improved tow haulage system, 11-6

Marmet Lock and Dam, Kanawha River,

11-4, 11-5

McAlpine Lock and Dam, Ohio River,

11-4, 11-5

Monongahela No. 4 Lock and Dam, 11-4,

11-5

Mississippi River locks, 11-4, 11-5

need for, 11-3

thin lock chamber walls, 11-3

Winfield Locks and Dam, Kanawha River,

114,11-5

intake manifolds (see Lock intake manifolds)

floor (see Lock floor)

gates (see Lock gates)

gravity locks, 8-4

guard walls, 5-3 (see also Lock approach walls)

guide walls, 5-3 (see also Lock approach walls)

Kanawha River, 8-5, 11-4, 11-5

lift, 5-3, 8-4 (see also Lock lift; High-lift locks;

Medium-lift locks ; Low-lift locks )

location, 8-1

criteria, 8-1, 9-1

channel width, 9-1

cross currents, 8-1, 9-1

sediment transport and deposition, 9-9

sight distance, 8-1, 9-1

lockage time, 3-2, 11-6

Lock and Dam 17, Verdigris River, 9-8

Lock and Dam 26, Mississippi River, 11-2

Lock .and Dam 26 replacement, Mississippi

River, 8-28

cofferdams, 8-31

Lower Granite Lock and Dam, Snake River,

8-22,841

Olmsted Locks and Dam, Ohio River, 7-2,

8-22,9-1, 9-4

Melvin Price Locks, Mississippi River, 8-1

mooring facilities, 8-12

multiple locks, 8-3

number of locks, 8-3

operation, 3-2, 3-3

1-6

Panama Canal Locks, 8-11

Red River Waterway, B-1

Lock and Dam 1, B-2, B-3, B-6

Lock and Dam 2, B-2, B-6

Lock and Dam 3, B-2, B-4

Lock and Dam 4, B-4

Lock and Dam 5, B-4

reinforced concrete locks, 8-4

reverse head, 8-6, 8-8, 8-14

Saint Anthony Falls Locks, Mississippi Ri

8-8

Saint Anthony Falls Lower Lock

lock miter gates, 8-35

submersible tainter gate, 8-36

sills (see Lock gates, gate sills)

size, 3-2

Snell Lock, Saint Lawrence Seaway, 8-4

steel sheet piling locks, 8-5

temporary locks, 8-5

Temporary Lock 52, Ohio River, 9-4

"twin locks", 8-1

types, 8-4

United States locks, 3-1, 3-2

walls (see Lock walls)

Locks and dams, 3-1

site criteria, 3-1, 4-1, 4-2, 4-3

in bends, 8-29

layout for low-lift dams, 8-26, 8-27

Locks and Dams 50 and 51, Ohio River, 8-2

Longitudinal floor culverts, 8-15, 8-16, 8-53, 8

8-55

baffles along walls and between culverts, 

8-23

Bankhead Lock, Black Warrior River, 8-5

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 8-55

combining culverts, 8-23

crossover culverts, 8-22, 8-23

culvert area ratio, 8-23

culvert distribution (location), 8-23

Dardanelle Lock, Arkansas River, 8-22, 8

filling and emptying times, 8-24

innovative design, 11-3

Lower Granite Lock, Snake River, 8-41

model data, 8-24

"over and under" system, 8-23, 8-54, 8-55

port/distribution culvert area ratio, 8-23

port manifold location, 8-23

ports, 8-23

access for inspection and maintenanc

8-23

size, 8-23
0

i

"side by side" system, 8-22, 8-53

Low-head dams

flow regimes, 7-3, 7-10

lock and dam layout, 8-27

overflow embankments, 7-2

spillways, 7-2

swellhead, 7-2

typical cross section, 4-4

Low-lift locks, 3-1

filling and emptying systems, 8-15, 8-16

layout, 8-27

Lower Granite Lock, Snake River, 8-22

floor culverts, 8-22

Maintenance dredging (see Dredging, maintenance

dredging)

Maintenance of navigation structures, 11-2

Lock and Dam 26, Mississippi River, 11-2

Marmet Lock and Dam, Kanawha River, 11-4

Marseilles Lock and Dam, Illinois River, 7-4

Mc Alpine Lock and Dam, Ohio River, 11-4

Medium lift locks, 8-1

filling and emptying systems, 8-15, 8-16

Melvin Price Locks and Dam, Mississippi River

(replacement for Locks and Dam 26),

8-1, 8-28, 11-2, 11-3

costs, 11-3

Mississippi River, 8-1, 8-2, 8-15, 11-1

cofferdams, 8-31

dredging, 10-5

flood of 1993, 8-9

ice, 7-5, 8-8

Locks and Dam 26 replacement, Mississippi

River (Melvin Price Locks and Dam),

8-1,8-28

Melvin Price Locks and Dam, 8-1, 8-28

Saint Anthony Falls locks

discharge laterals, 8-21

Upper lock, 8-35

tainter gates, 8-8

Upper Mississippi River, 7-5

canalization, 10-14, 11-1

traffic, 11-2, 11-8

Mitigation measures

migratory fish, 6-2

Models

Bay Springs Lock, Tennessee-Tombigbee

Waterway

air entrainment, 9-8

I-7

canal surge, 9-7

filling and emptying time, 9-7

intake design, 9-8

outlet diffuser design, 9-8

valve operating time, 9-7

vortex action, 9-8

Dardanelle Lock and Dam, 9-2

effect of wing dikes on shoaling in lower

approach, 9-9

innovaative design models, 11-3, 11-4

intake models, 11-5

Lock and Dam 2, Red River, 9-2

longitudinal floor culverts

filling time, 8-24

emptying time, 9-7

navigation conditions in lock approaches, 9-2,

9-3

Olmsted Locks outlet works, 9-4

riprap stability at outlet, 9-4

Robert S . Kerr Lock and Dam, Arkansas River

9-2

spillway models, 7-3

surge conditions, 9-7

tow squat, 9-6

Monongahela River No. 4 Lock and Dam, 11-4,

11-5

Mosquito control, 6-2, 6-5

N

Navigation channel

authorized dimensions, 10-10

overdepth dredging 10-10

width, 5-2, 5-5

width in bends, 5-5

Navigation dams, 7-1 (see also Low-head dams)

Arkansas River, 7-1, 7-8

effect of flood heights, 6-1

fixed, 7-1

height, 6-1

movable, 7-1, 7-6, 7-8

Babout self-tripping wicket, 7-6

bear-trap dam, 7-6

Chanoine wicket, 7-6

Chanoine-Pescaud wicket, 7-6

Olmsted Locks and Dam, Ohio River, 7-7

wicket gates, 7-7

navigable pass, 7-1

Red River, 7-1

site selection affected by location of wate

intakes, sewer outfalls, etc ., 6-1, 6-2
spacing, 3-3

typical low-head dam, 4-4

wicket gates, 7-1, 7-7

Navigation development

canalized, 1-2

canals, 1-2

cost sharing, 11-3

Federal funding, 11-3

in United States, 11-1

Mississippi River, 11-1

Ohio River, 11-1

open-river, 1-2

Navigation equipment

design tow size, United States, 3-2

tow size (see Tow size)

terminals, 5-4

Navigation locks (see Locks)

Navigation hazards, 9-1

currents, 9-1

Dardanelle Lock and Dam, Arkansas River, 9-2

expansion eddies, 9-1

flood stages, 9-1

high velocities, 9-1

lock .emptying system, 9-1

lower approach, 9-1

Lock and Dam 2, Red River, 9-2

power plant discharges, 9-1

sediment, 9-1

shoaling, 9-1

spillway discharges, 9-1

surges, 9-1

tow squat, 9-1

Navigation pass, 7-1

Navigation pool level

effects on fish and wildlife, 6-2

effects on water supply intakes, 6-1

effects on local drainaage, 6-1

operation for vector control, 6-2, 6-5

Navigation - projects

components of projects, 1-3

channel width, 5-2

criteria for design, 5-1, 5-2, 5-3, 5-4

design requirements, 6-1

hazardous currents, 5-3

hydropower development, 6-3

minimum depth, 5-21

objectives in developing, 1-1

recreation use of navigation pools, 6-3

transit time, 5-3

terminal facilities, 5-4

ways to develop, 1-1

Navigation structures

site selection, 4-1, 4-2, 4-3

1-8

New Cumberland Locks, Ohio River, 8-21

O

Ohio River

canalization, 7-2, 11-1

Gallipolis Locks vortex action, 8-18

Greenup Locks, 8-40

Olmsted Locks and Dam, 7-2, 8-22, 9-1, 9-4

Smithland Locks, 8-2, 8-30

Temporary Lock 52, 9-4

traffic, 11-1, 11-8

Olmsted Locks and Dam, Ohio River, 7-2, 7-9,

8-22, 9-1, 9-4

emptying system, 9-4

layout, 7-9

Open-river spillway operation, 10-3

Overflow embankments, 7-2

P

Panama Canal Locks, 8-11

Planning

canalization, 2-1

project life, 2-1

site selection, 4-1, 4-2, 4-3

Ports

deflectors, 8-48

for 110-ft lock, 8-48

in approach walls to reduce currents, 9-2

in upper guard wall, Dardanelle Lock, 9-2

in upper guide wall, Lock and Dam 2, Red

River, 9-2

TVA multiport system, 8-48

R

Reaeration, 7-2, B-4

Red River Waterway, 7-1, 7-3, 7-4, 9-3, B-1

costs, 11-3

hinged crest spillway, 7-2

hinged pool operation (see Hinged pool

operation)

Lock and Dam 1

layout, 10-15

sediment deposition (see Sediment

deposition, Red River Waterway)

submersible pump, 10-6

Lock and Dam 2
ports in upper guide wall, 9-2

submerged dikes in upstream approach, 9-2

locks, B-1, B-2

project description B-1, B-6

reaeration of spillway discharge, 7-2, B-4

sediment deposition (see Sediment deposition,

Red River Waterway)

sediment load, B-2

spillways, B-1, B-4, B-5, B-9

design optimization, B-4, B-5, B-10

stilling basins B-1

Reoxygenation (see Reaeration)

Robert S . Kerr Lock and Dam, Arkansas River, 9-3

cross currents, 9-3

eddies in lower lock approach, 9-4

ports in upper guide wall, 9-3

Reservoir operating criteria

to reduce shoaling, 10-2

Saint Anthony Falls Locks, Mississippi River, 8-8

Lower Lock discharge laterals, 8-21

fainter gates, 8-8

Upper lock, 8-35

Vortex action at Lower Lock, 8-17

Saint Lawrence Seaway, 8-40

Snell Lock emptying system, 8-21

Sector gates (see Lock gates, sector gates)

Sediment deposition (see also Shoaling in lock

approaches)

Red River Waterway

at miter gates, 10-6, B-2, B-6

drains in sill to prevent, B-2

in lock chamber, 10-6

Lock and Dam 1, B-2, B-3, B-6

1984. 1-6

1990,10-6

Lock and Dam 2, B-7

Sheet piling locks, 8-5

Shoaling in lock approaches, 9-9

Dardanelle Lock lower approach, 9-9

effect of ports in upsteam guide wall, 9-9

effect of wing dikes, 9-9

in lower lock approach, 9-9

in upper lock approach, 9-9

minimized by reservoir operation, 10-2

minimized by hinged pool operation, 10-7

Red River Waterway, B-3

Lock and Dam 1, B-3, B-6

Sight distance (see Locks, location)

Sills (see Lock gates, sills)

effect of channel widening, 9-8, 9-30

1-9

Site access for construction and operation, 8-3

Smithland Locks and Dam, Ohio River, 8-2, 8-

Snake River, 8-23 (see also Lower Granite Loc

Snell Lock, Saint Lawrence Seaway

emptying system, 8-21

Spillways

baffled spillway, 7-3, B-4, B-9

cross currents at locks, 8-1

design optimization, B-4, B-5, B-10

flow regimes, 7-3

hinged crest, 7-2, B-9

hydraulic models, 7-3

low-lift navigation dams, 7-2

passing ice and debris, 7-3, 7-4, 7-5

reaeration, 7-2, B-4

Red River Waterway dams, B-1

uncontrolled crests, B-1

Spillway gates

flap gates, 7-14

hinged crest gates, 7-2, 7-4, 7-14, B-4, B-9

Red River Waterway locks and dams, 7-2, 

roller gates, 7-4, 7-13

submergible gates, 7-3

Illinois River, 7-4

Marseilles Lock, Illinois River, 7-12, 

tainter gates, 7-3, 7-11

types, 7-3

vertical lift gates, 7-4, 7-14

Spillway piers

ogival pier nose, 7-8

pier shape, 7-5, 7-8

semicircular pier nose, 7-8

Squat (see Tow squat)

Streamflow

maximum navigable flow, 8-9

Submerged dikes (see Dikes)

Submersible pump to remove sediment, 10-6, 10

T

Tainter gates

spillway gates, 7-3, 7-8

"reverse" fainter gates in culverts, 8-18

Tennessee-Tombigbee Waterway, 8-7, 9-6 (see 

Bay Springs Lock)

canal surge, 9-7

Tennessee Valley Authority

filling and emptying systems, 8-15

multiport system, 8-20, 8-48

Terminal facilities

site criteria, 5-4
effect of open emptying valves, 9-6, 9-19, 9-20

effect of propeller speed, 9-6

types of squat

displacement squat, 9-5

moment squat, 9-6, 9-19

piston squat, 9-5, 9-19

propeller squat, 9-6

Verdigris River

effect of channel deepening, 9-9, 9-29,

9-30

effect of channel widening, 9-8, 9-30

Trashracks, 8-17

Valve opening time, 8-47, 9-7, 11-6

Bay Springs Lock, Tennessee-Tombigbee

Waterway, 9-7

Vector control, 6-2, 6-5

Velocities

in lower lock approach, 9-3

limiting navigation B-1

Verdigris River, 9-8, 9-27

Vortex action

Bay Springs Lock, 9-8

Gallipolis Locks, Ohio River, 8-18

lock intake ports, 8-17

model studies, 8-17, 8-18

port submergence, 8-17

Saint Anthony Falls Lower Lock, 8-17

W

Walls (see Lock walls)

I-10