Authorization

The project was authorized by the River and Harbor Act of 1945.

 

Progress

Little Goose Dam construction started in June 1963. The filling of Lake Bryan began on Feb. 16, 1970, and continued until elevation 638 feet was reached on Feb. 25, 1970. The Ice Harbor Lock was open to navigation in May 1970. The installation of power generating units one through three was completed, and the first unit began producing power in March 1970. Additional power units four through six were installed and power for those units came online in July 1978. Revisions were made to the juvenile fish facility in 1982 and 1984.

 

Project

The project includes a dam, navigation lock, power plant, fish ladder and appurtenant facilities. It provides navigation, hydropower generation, fish and wildlife habitat, recreation and incidental irrigation.

 

Little Goose Dam

The dam is 3,200 feet long with an effective height of about 100 feet. It is located on the Snake River near Starbuck, Wash., and upstream of Lake West, the reservoir formed by Lower Monumental Dam. It is a concrete gravity dam with an earthfill abutment embankment. It includes a navigation lock and eight-bay spillway 512 feet long, which has eight 50-feet by 60-feet tainter gates.

 

Navigation Lock

Little Goose has a single-lift lock, 86 feet wide by 668 feet long, with a 100-foot vertical lift. 2,490,523 tons of commodities passed through the Little Goose navigation lock during fiscal year 2021.

 

Reservoir

Lake Bryan extends upstream about 37.2 miles and provides navigation to Lower Granite Lock and Dam. It has a surface area of 10,025 acres.

 

Hydroelectric Generators

The powerhouse has six 135,000-kilowatt units – 810-megawatt total powerhouse capacity. During fiscal year 2017, 2.87 billion kilowatt hours of electricity were produced.

 

Fish Passage

Adult fish passage facilities include one fish ladder with entrances on both shores and a fish channel through the spillway, which connects to the powerhouse fish collection system and south shore ladder. Modifications to improve adult Pacific lamprey passage include ladder improvements, passage structures and installation of metal plating to assist lamprey upstream. A juvenile bypass outfall has avian deterrents installed to limit perching near the release location by piscivorous birds. This system was modified several times. The 10-year average collection of outgoing juvenile salmon and steelhead for 2011 to 2020 at Little Goose was approximately 3.2 million fish with approximately 2.4 million of those transported via truck and barge below Bonneville Dam. In 2009, a spillway weir was installed to improve conditions for juvenile salmon passage at the dam. A passive integrated transponder (PIT)-tag monitoring system was completed prior to the 2009 fish passage season. This system improved detection of downstream migrating PIT-tagged juveniles.

 

Lands

There are 5,398 acres of project lands surrounding Lake Bryan. These lands include fee lands that are federally owned and managed by the U.S. Army Corps of Engineers (USACE) as well as easement lands to which USACE has specific rights or easements (i.e., flowage or access). There are 5,142.9 acres of USACE-managed lands used for public recreation purposes, wildlife habitat, wildlife mitigation, and water-connected industrial development. Two areas totaling approximately 150 acres are licensed either to the state or local port for recreation. Lake Bryan provides seven day-use sites, five campgrounds, five boat launching areas and two swimming areas. During fiscal year 2020, Little Goose hosted 225,747 visits.

 

People

About 50 Walla Walla District employees work at the Little Goose project. They serve as electricians, lock operators, mechanics, welders, riggers, painters, utility workers, heavy equipment operators, park rangers, biologists, environmental resource specialists, administrative staff, engineers and maintenance workers. Together, they manage the safe and continuous operation of the project.

 

Recreation

Little Goose project lands provide opportunities for all sorts of recreational activities, including fishing, hunting, hiking, birding, camping, swimming and horseback riding. Amenities within the parks include boat launches, campsites, shelters, fire rings, and picnic tables.

 

General
Location:
State - Washington
County - Columbia and Whitman
River - Snake
River Mile - 70.3
River miles upstream from Ice Harbor Dam - 28.7

Owner - U.S. Army Corps of Engineers, Walla Walla District
Authorized Purpose - Power generation and inland navigation
Other Uses - Fishery and recreation
Type of Project - Run-of-river

Real Estate:
Fee acquisition land above pool elevation 638 - 11,179 acres

Reservoir
Name - Lake Bryan (Reference 1)
Elevations (Feet Mean Sea Level):
Maximum at dam for spillway design flood - 646.5
Normal operating range gauged at dam - 638 to 633

At Pool Elevation 638:
Length – 37.2 miles
Length of shoreline – 92 miles
Average width – 0.4 miles
Maximum width – 0.8 miles
Surface area (low flow, 30,000 cfs or less) – 10,025 acres

Storage below elevation 638 (low flow) - 565,200 acre-feet
Storage below elevation 633 (low flow) - 516,300 acre-feet
Storage between elevations 633 and 638 - 48,900 acre-feet
Height normal high pool elevation 638 to tailwater elevation 540 (low flow, 30,000 cfs or less) - 98 ft

Dam (General)
Axis (Lambert) - N 10° 57'W
Length and Widths, feet:
Dam total length at crest – 2,655 ft
North abutment embankment – 787.5 ft
North non-overflow monoliths length – 189 ft
Spillway overall length (between abutment centerline) – 512 ft
Spillway to powerhouse non-overflow – 48.5 ft
Powerhouse overall length – 656 ft
Powerhouse to navigation lock non-overflow length – 57 ft
Navigation lock overall width – 328 ft
Concrete Heights, feet:
Maximum overall concrete height (powerhouse sump deck to deck) – 253 ft
Maximum non-overflow monoliths height (north) – 200 ft
Maximum lock wall monolith height (culverts to deck) – 165 ft

Deck elevations, feet msl:
Intake, spillway bridge, non-overflow sections, and upstream end of navigation lock – 651 ft msl
Downstream end of navigation lock – 646 ft msl
South shore fish ladder – 558 ft msl
Tailrace and fishwater intake – 558 ft msl
North abutment embankment – 656 ft msl

Spillway
Number of Bays - 8
Overall length (abutment centerlines) – 512 ft
Deck elevation – 651 ft msl
Ogee crest elevation – 581 ft msl
Flip lip elevation – 532

Control gates:
Type - Tainter
Size - 50'W x 60'H

Gantry crane (joint use with powerhouse) capacity – 100 tons
Stilling basin length – 118 ft
Stilling basin elevation – 466.5 ft msl
Maximum design capacity – 850,000 cfs

Powerhouse
Length overall – 656 ft
Spacing, feet:
Units 1 through 5 – 90
Unit 6 – 96
Erection and service bay – 110
Width overall, transverse section – 243 ft
Maximum height (draft tube invert to intake deck) – 226 ft

Turbines:
Type – Kaplan, 6-blade
Runner diameter – 312 in
Revolutions per minute – 90
Rating horsepower – 212,400
Distributor centerline elevation - 501

Generators:
Rating (nameplates) – 135,000 kilowatts
Power factor – 0.95
Kilovolt ampere rating – 142,100
Units installed complete initially - 3
Skeleton units provided initially - 3
Total units now installed - 6
Plant capacity, nameplate rating – 810,000 kilowatts

Crane capacities, tons:
Intake (joint use with spillway) - 100
Bridge - 600
Draft tube gantry - 50

Navigation Lock and Channels
Net clear length, lock chamber - 668 ft
Net clear width, lock chamber - 86 ft
Operating water surface elevations in chamber - 537 to 638
Maximum operating lock lift - 101 ft

Upstream gate:
Type – Submersible tainter
Height – 22 ft

Downstream gate:
Type - Miter
Height - 85 ft

Length of guidewalls (from face of gate), feet:
Upstream (floating) - 665
Downstream - 700

Downstream approach channel:
Width – 250 ft
Bottom elevation – 521

Lower lock sill elevation - 522 ft
Upper lock sill elevation - 618 ft
Maximum depth over sills - 20 ft
Minimum depth over sills - 15 ft

Abutment Embankment
Embankment elevation - 656
Embankment top width - 43 ft

Material - Gravel ill with rock facing impervious silt core
Upstream - Combination sand and gravel filters
Downstream - Gravel and sand filters

Slope, upstream - 1V on 2H
Slope, downstream - 1V on 2H

Fish Facilities
Upstream migrants fish ladder:
Number of fish ladders - 1
Slope – 1V on 10H
Ladder clear width – 20 ft
Design capacity – 75 cfs

Exit Channel:
Location - Between weir 637 and pool in non-overflow section
Top of trashrack elevation - 632
Invert elevation - 627
Width - 6 ft

Normal operating range:
Pool elevations – 633 to 638
Tailwater elevations – 537 to 544
Riverflow – 0 to 225,000 cfs

Maximum operating range:
Pool elevations – 632 to 639
Tailwater elevations – 537 to 547.5
Riverflow – 0 to 340,000 cfs

Pumps for fish attraction water:
Number - 3
Rated capacity – 2,550 cfs

Downstream migrants:
Traveling fish screens - 18
Fingerling collection gallery - 1
Fingerling transportation pipe - 1
Fingerling handling facility - 1

Fingerling transportation facilities:
Truck loading facility - 1
Barge loading facility - 1
Design pool range - 633 to 638

Hydrologic Data
(Based on streamflow data for the Snake River near Clarkston, Washington)
Drainage area - 103,200 square miles
Period of Record - October 1915 to September 1972 (Discontinued in December 1972)

Discharges, cfs:
Instantaneous maximum of record, 29 May 1948 – 369,000 cfs
Instantaneous minimum of record, 2 September 1958 – 6,600 cfs
Average annual flow – 50,300 cfs
Average annual mean daily peak flow – 188,300 cfs
Extreme outside period of record:
Flood of June 1894 – 409,000 cfs
Flood of June 1894, controlled by existing projects – 295,000 cfs

Standard project flood, controlled by existing projects:
Snake River below Clearwater River – 420,000 cfs
Snake River above Clearwater River – 295,000 cfs
Clearwater River above Snake River – 150,000 cfs
Spillway design flood – 850,000 cfs

References
(1)For the purpose of continuity with existing Little Goose Lock and Dam documents, the use of the term "pool" or "reservoir" is used interchangeably. The term "lake" is used only to designate a geographical body of water.