Garrison Dam

Garrison Dam
Location of Garrison Dam in North Dakota
Country	United States
Location	Lake Sakakawea, at McLean / Mercer counties, North Dakota
Coordinates
Status	Operational
Construction began	1947
Opening date	1953
Construction cost	US$300 million
Dam and spillways
Type of dam	Embankment, rolled earth-fill
Height	210 ft (64 m)
Length	11,300 ft (3,444 m)
Width (crest)	60 ft (18 m)
Width (base)	0.5 mi (1 km)
Dam volume	66,500,000 cu yd (50,842,898 m3)
Spillway type	Service, 28 controlled-gates
Spillway capacity	660,000 cu ft/s (18,689 m3/s)
Reservoir
Total capacity	23,821,000 acre·ft (29.383 km3)
Surface area	382,000 acres (1,546 km2)
Max. length	178 mi (286 km)
Normal elevation	1,854 ft (565 m) (max)
Power station
Commission date	January 1956–October 1960
Turbines	3 x 121.6 MW, 2 x 109.25 Francis type
Installed capacity	583.3 MW
Annual generation	2,250 GWh

Garrison Dam is an earth-fill embankment dam on the Missouri River in central North Dakota, constructed 1947-1953. The Three Affiliated Tribes owned the land needed to flood. Short of confiscation by eminent domain the tribes protested and achieved remuneration, but lost 94% of their agricultural land. Constructed by the U.S. Army Corps of Engineers from 1947-53 at over two miles (3 km) in length, the dam is the fifth-largest earthen dam in the world. The reservoir impounded by the dam is Lake Sakakawea, which extends to Williston and the confluence with the Yellowstone River, near the Montana border.

Location

Garrison Dam is located between Riverdale and Pick City, named after the town of Garrison, directly north of the dam, across the reservoir. The dam is approximately midway between Bismarck and Minot, about 10 miles (16 km) west of U.S. highway 83.

History

The dam was part of a flood control and power generation project named the Pick-Sloan Project along the river, after the two plan developers, Colonel Lewis A. Pick and William Glenn Sloan. In order to construct the dam, the US government needed to purchase 152,360 acres (616.6 km²) in the Fort Berthold Reservation that would be flooded by the creation of Lake Sakakawea. These lands were owned by the Three Affiliated Tribes, who had been living there "had been their home for perhaps more than a millennium". Threatened by confiscation under eminent domain the tribes protested. A complete block of Garrison Dam power was denied because it would violate the 1935 Rural Electrification Act. The tribes achieved remuneration, but lost 94% of their agricultural land. in 1947, when they were forced to accept $5,105,625, increased to $7.5 million in 1949. The final settlement legislation denied tribes' right to use the reservoir shoreline for grazing, hunting, fishing, or other purposes, including irrigation development and royalty rights on all subsurface minerals within the reservoir area. About 1700 residents were forcibly relocated, some to New Town, North Dakota. Thus Garrison Dam almost totally destroyed the traditional way of life for the Three Affiliated Tribes. Construction on the $300 million dam project began in 1947, and its embankment was enclosed in April 1953. The dam was dedicated by President Eisenhower two months later. The Corps of Engineers completed earthwork in the fall of 1954.

In June 2011, in response to the 2011 Missouri River Floods, the dam was releasing over 140,000 cubic feet per second (4,000 m³/s), which greatly exceeded its previous record release of 65,000 cu ft/s (1,800 m³/s) set in 1997. The first use of the emergency spillway due to flooding started on June 1, 2011 at 8:00am.

Energy generation

Hydropower turbines at Garrison Dam have an electric power generating nameplate capacity of 583.3 megawatts. Average production of 240 megawatts serves several hundred thousand customers.

Fishing

The Garrison Dam National Fish Hatchery is the world's largest walleye and northern pike producing facility and also works to restore endangered species, such as the pallid sturgeon.

External links

• Discover ND.com - Garrison Dam: A Half Century Later - June 2003
• U.S. Fish and Wildlife Service - Garrison Dam
• Mandan, Hidatsa, & Arikara Nation.com - article on the Garrison Dam