Hungry Horse Dam

Hungry Horse Dam
Location of Hungry Horse Dam in Montana
Location	Flathead County, near Columbia Falls, Montana, USA
Coordinates
Construction began	April 21, 1948
Opening date	July 18, 1953
Operator(s)	U.S. Bureau of Reclamation
Dam and spillways
Type of dam	Concrete thick arch dam
Impounds	South Fork Flathead River
Height	564 ft (172 m)
Length	2,115 ft (645 m)
Width (crest)	34 feet (10 m)
Width (base)	320 feet (98 m)
Dam volume	2,934,500 cu yd (2,243,600 m3)
Spillway type	Gated Morning Glory
Spillway capacity	50,000 cu ft/s (1,400 m3/s)
Reservoir
Creates	Hungry Horse Reservoir
Total capacity	3,467,179 acre-feet (4.276702 km3)
Catchment area	1,640 sq mi (4,200 km2)
Power station
Type	Conventional
Hydraulic head	520 ft (160 m)
Turbines	4 x 107 MW Francis turbines
Installed capacity	428 MW
Annual generation	906,720,100 KWh (2007)

Hungry Horse Dam is an arch dam on the South Fork Flathead River in the Rocky Mountains of the U.S. state of Montana. It is located in Flathead National Forest, in Flathead County, about 15 miles (24 km) south of the west entrance to Glacier National Park, 9 miles (14 km) southeast of Columbia Falls, and 20 miles (32 km) northeast of Kalispell. The Hungry Horse project, dam, and powerplant are operated by the United States Bureau of Reclamation. The entrance road leading to the dam is located in Hungry Horse, Montana.

Dimensions and statistics

Bell-mouth spillway of Hungry Horse Dam in operation.

At 564 feet (172 m) in height, the dam was the third largest and second highest concrete dam in the world at the time of its completion in 1953, with a volume of 3,100,000 cubic yards (2,400,000 m³). The dam's spillway is the highest morning glory structure in the world. The spillway is controlled by a 64-by-12-foot (19.5 by 3.7 m) ring gate.

History

Construction of Hungry Horse Dam was authorized by the Act of June 5, 1944 (58 Stat. 270, Public Law 78-329). Construction began in April 1948 and completed in July 16, 1953. The purposes of the Hungry Horse Project authorized by law are irrigation, flood control, navigation, streamflow regulation, hydroelectric generation, and other beneficial uses such as recreation. However, no irrigation facilities were built and the project has no irrigation obligations. Hydroelectric power generation is the primary purpose of the dam today. Flood control is the dam's other main purpose. The dam, reservoir, and surrounding area are used for recreation.

Hydroelectric power generation

The project contributes to hydroelectric power generation not only at Hungry Horse Dam, but by storing and releasing water for use by downriver hydroelectric dams on the Flathead River, Clark Fork, Pend Oreille River, and Columbia River. About a billion kilowatt–hours are generated annually at Hungry Horse Dam, while in an average year the release water will generate about 4.6 billion kilowatt–hours of power as it passes through the series of downstream powerplants.

Power generating facilities at Hungry Horse Dam are housed in a building constructed across the river channel at the downstream toe of the dam. The original design included four 71,250-kilowatt generators—a total of 285 megawatts installed capacity. The generator capacity was uprated in the 1990s to 107,000 kilowatts each for a total capacity of 428 megawatts.

See also

• List of dams in the Columbia River watershed

External links

• U.S. Geological Survey Geographic Names Information System: Hungry Horse Dam