| Garrison Dam | |
|---|---|
 Aerial view from the southeast, impounding Lake Sakakawea on the Missouri River | |
  Location in the United States  Location in North Dakota | |
| Country | United States |
| Location | McLean/Mercer counties, North Dakota |
| Coordinates | 47°29′55″N 101°24′43″W / 47.49861°N 101.41194°W |
| Status | Operational |
| Construction began | 1947 |
| Opening date | 1953 |
| Construction cost | $300 million |
| Owner(s) | U.S. Army Corps of Engineers, Omaha District |
| Dam and spillways | |
| Type of dam | Embankment, rolled earth-fill |
| Impounds | Missouri River |
| Height | 210 ft (64 m) |
| Length | 11,300 ft (3,444 m) |
| Elevation at crest | 1,854 feet (565 m) msl |
| Width (crest) | 60 ft (18 m) |
| Width (base) | 0.5 mi (0.8 km) |
| Dam volume | 66,500,000 cu yd (50,843,000 m3)[1] |
| Spillway type | Service, 28 controlled-gates |
| Spillway capacity | 660,000 cu ft/s (18,700 m3/s)[2] |
| Reservoir | |
| Creates | Lake Sakakawea |
| Total capacity | 23,821,000 acre⋅ft (29.383 km3)[2] |
| Catchment area | 123,900 m2 (1,334,000 sq ft) |
| Surface area | 382,000 acres (1,550 km2) |
| Maximum length | 178 mi (286 km) |
| Maximum water depth | 180 ft (55 m) |
| Normal elevation | 1,854 ft (565 m) (max) |
| Power Station | |
| Operator(s) | U.S. Army Corps of Engineers |
| Commission date | January 1956–October 1960[2] |
| Turbines | 3 x 121.6 MW, 2 x 109.25 Francis type |
| Installed capacity | 583.3 MW[3] |
| Annual generation | 2,250 GWh (1967-2009 Average)[2] |
| Website www | |
Garrison Dam is an earth-fill embankment dam on the Missouri River in central North Dakota, U.S. Constructed by the U.S. Army Corps of Engineers from 1947 to 1953, at over two miles (3.2 km) in length, the dam is the fifth-largest earthen dam in the world.[4] The reservoir impounded by the dam is Lake Sakakawea, which extends to Williston and the confluence with the Yellowstone River, near the Montana border. The dam and resulting reservoir inundated approximately one-sixth (16.6%) to one-fourth (25%) of Fort Berthold Indian Reservation's land, resulting in the loss of homes, farmland, and community infrastructure for the Three Affiliated Tribes.
- ^ "Garrison Dam/ Powerplant". U.S. Army Corps of Engineers. Archived from the original on 24 October 2004. Retrieved 19 June 2011.
- ^ a b c d "Summary of Engineering Data – Missouri River Main Stem System" (PDF). Missouri River Division. U.S. Army Corps of Engineers. August 2010. Archived from the original (PDF) on 2013-02-16. Retrieved 2012-08-17.
- ^ "Facts about Garrison Dam and power plant" (PDF). U.S. Army Corps of Engineers. n.d. Archived from the original (PDF) on 1 June 2011. Retrieved 19 June 2011.
- ^ "Garrison Dam and Powerplant". U.S. Army Corps of Engineers. Archived from the original on October 24, 2004.