Lower Monumental Dam
| Lower Monumental Dam | |
|---|---|
 View from the southwest | |
| Location | Franklin and Walla Walla counties, Washington, U.S. |
| Coordinates | 46°33′47″N 118°32′20″W / 46.563°N 118.539°WCoordinates: 46°33′47″N 118°32′20″W / 46.563°N 118.539°W |
| Construction began | June 1961 |
| Opening date | 1969 |
| Operator(s) | U.S. Army Corps of Engineers |
| Dam and spillways | |
| Type of dam | Concrete gravity, run-of-the-river |
| Impounds | Snake River |
| Height | 100 feet (30 m) |
| Length | 3,791 feet (1,155 m) |
| Spillway type | Service, gate-controlled |
| Reservoir | |
| Creates | Lake Herbert G. West |
| Total capacity | 432,000 acre⋅ft (0.53 km3)[1] |
| Surface area | 6,590 acres (26.7 km2) |
| Normal elevation | 540 ft (165 m) |
| Power Station | |
| Turbines | 6 x 135-153 MW[2] |
| Installed capacity | 810 MW 932 MW (max) |
Lower Monumental Lock and Dam is a hydroelectric, concrete, run-of-the-river dam in the northwest United States. Located on the Snake River, it bridges Franklin and Walla Walla counties in southeast Washington.[3][4] It is six miles (10 km) south of Kahlotus and 43 miles (70 km) north of Walla Walla.
Construction began in June 1961, and the main structure and three generators were completed in 1969, with an additional three generators finished in 1981. Generating capacity is 810 megawatts, with an overload capacity of 932 MW. The spillway has eight gates and is 572 feet (174 m) in length.
Lower Monumental Dam is part of the Columbia River Basin system of dams.
Behind the dam, Lake Herbert G. West is the reservoir; it extends 28 miles (45 km) east to the base of Little Goose Dam. Lake Sacajawea, formed from Ice Harbor Dam, runs 22 miles (35 km) southwest, downstream from the base of the dam.
- Navigation lock
- Single-lift
- Width: 86 ft (26 m)
- Length: 666 ft (203 m)
See also[]
References[]
- ^ "The Four Lower Snake River Dams". Bluefish.org. Retrieved 17 July 2010.
- ^ "Lower Monumental Dam". Washington.edu. Retrieved 17 July 2010.[dead link]
- ^ "Lower Monumental Dam". Lewiston Morning Tribune. (Idaho). (photo). March 19, 1964. p. 13.
- ^ "The Columbia River System Inside Story" (PDF). BPA.gov. pp. 14–15. Retrieved 17 July 2010.
External links[]
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Wikimedia Commons has media related to Lower Monumental Dam. |
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- Dams in Washington (state)
- Dams on the Snake River
- Gravity dams
- Hydroelectric power plants in Washington (state)
- Run-of-the-river power stations
- Buildings and structures in Franklin County, Washington
- Buildings and structures in Walla Walla County, Washington
- Dams completed in 1969
- 1969 establishments in Washington (state)
- Energy infrastructure completed in 1969
- Energy infrastructure completed in 1981
- United States Army Corps of Engineers dams