Jackson Lake Dam is a

concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wi ...

and earth-fill

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use ...

in the

western Western may refer to: Places *Western, Nebraska, a village in the US *Western, New York, a town in the US *Western Creek, Tasmania, a locality in Australia *Western Junction, Tasmania, a locality in Australia *Western world, countries that id ...

United States, at the outlet of Jackson Lake in northwestern

Wyoming Wyoming () is a U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the south ...

. The lake and dam are situated within

Grand Teton National Park Grand Teton National Park is an American national park in northwestern Wyoming. At approximately , the park includes the major peaks of the Teton Range as well as most of the northern sections of the valley known as Jackson Hole. Grand Teton Na ...

in Teton County. The

Snake River The Snake River is a major river of the greater Pacific Northwest region in the United States. At long, it is the largest tributary of the Columbia River, in turn, the largest North American river that empties into the Pacific Ocean. The Snake ...

emerges from the dam and flows about through Wyoming,

Idaho Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

, and

Washington Washington commonly refers to: * Washington (state), United States * Washington, D.C., the capital of the United States ** A metonym for the federal government of the United States ** Washington metropolitan area, the metropolitan area centered o ...

to its mouth on the

Columbia River The Columbia River (Upper Chinook: ' or '; Sahaptin: ''Nch’i-Wàna'' or ''Nchi wana''; Sinixt dialect'' '') is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, C ...

eastern Eastern may refer to: Transportation *China Eastern Airlines, a current Chinese airline based in Shanghai *Eastern Air, former name of Zambia Skyways *Eastern Air Lines, a defunct American airline that operated from 1926 to 1991 *Eastern Air Li ...

Washington. The chief purpose of the dam is to provide water storage for irrigation in the Snake River basin in the state of Idaho as part of the

Minidoka Project The Minidoka Project is a series of public works by the U.S. Bureau of Reclamation to control the flow of the Snake River in Wyoming and Idaho, supplying irrigation water to farmlands in Idaho. One of the oldest Bureau of Reclamation projects in t ...

. Jackson Lake is a natural lake, but its depth was increased by the dam to provide water storage.

History

The first Jackson Lake Dam was a log-crib dam constructed in 1906–07 across the outlet of Jackson Lake, a natural lake. That dam raised the lake level by , but the dam failed in 1910. A new concrete and earthen dam was constructed in stages between 1911 raising the maximum lake level to above the lake's natural elevation, providing a storage capacity of . The new dam was designed by Frank A. Banks, who would later supervise the construction of

Grand Coulee Dam Grand Coulee Dam is a concrete gravity dam on the Columbia River in the U.S. state of Washington, built to produce hydroelectric power and provide irrigation water. Constructed between 1933 and 1942, Grand Coulee originally had two powerh ...

. The reservoir was created by damming the outlet of the natural glacial Jackson Lake, with the additional height creating a storage pool for the

, which provides irrigation water from the Snake River for farmlands in Idaho. Jackson Lake stores and releases water which is collected by

Minidoka Dam The Minidoka Dam is an earthfill dam in the western United States, on the Snake River in south central Idaho. Completed in 1906, the dam is east of Rupert on county highway 400; it is high and nearly a mile (1.6 km) in length, with a wide o ...

and

American Falls Dam The American Falls Dam is a concrete gravity-type dam located near the town of American Falls, Idaho, on river mile 714.7 of the Snake River. The dam and reservoir are a part of the Minidoka Project on the Snake River Plain and are used primaril ...

more than downstream for diversion to distribution canals. At the time of the dam's construction,

Jackson Hole Jackson Hole (originally called Jackson's Hole by mountain men) is a valley between the Gros Ventre and Teton mountain ranges in the U.S. state of Wyoming, near the border with Idaho, in Teton County, one of the richest counties in the Unit ...

and the

Teton Range The Teton Range is a mountain range of the Rocky Mountains in North America. It extends for approximately in a north–south direction through the U.S. state of Wyoming, east of the Idaho state line. It is south of Yellowstone National Park and ...

were as yet unprotected from development. Grand Teton National Park was established in 1929, and excluded Jackson Lake. The lake was incorporated into Jackson Hole National Monument when it was proclaimed by President

Franklin D. Roosevelt Franklin Delano Roosevelt (; ; January 30, 1882April 12, 1945), often referred to by his initials FDR, was an American politician and attorney who served as the 32nd president of the United States from 1933 until his death in 1945. As the ...

under the

Antiquities Act The Antiquities Act of 1906 (, , ), is an act that was passed by the United States Congress and signed into law by Theodore Roosevelt on June 8, 1906. This law gives the President of the United States the authority to, by presidential procla ...

, and became a part of Grand Teton National Park in 1950 when the park was expanded to encompass the national monument lands. When the dam was built there was no attempt to clear the shores of the lake of standing timber, resulting in an unsightly band of dead trees when the waters rose. This vista, and the mudflats created by drawdown of lake waters, were cited in later years in successful arguments against reservoirs in

Yellowstone National Park Yellowstone National Park is an American national park located in the western United States, largely in the northwest corner of Wyoming and extending into Montana and Idaho. It was established by the 42nd U.S. Congress with the Yellowston ...

. Construction personnel for the dam were housed at a temporary camp that dwarfed the nearby town of Moran. Supplies came in from the Grassy Lake Road north of the park, which runs west into Idaho to meet the nearest railhead at

Ashton, Idaho Ashton is a city in Fremont County, Idaho, United States. The population was 1,127 at the 2010 census, and it is part of the Rexburg Micropolitan Statistical Area. The district is noted for seed potato production and bills itself as the world's ...

Reinforcement

The U.S. Bureau of Reclamation conducted studies on dams in 1976 and determined that Jackson Lake Dam was susceptible to failure in case of an earthquake of

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

5.5 or greater. Following the Borah Peak earthquake of 1983 in Idaho, the dam was upgraded during 1986–1989, and the Bureau of Reclamation believed it could withstand the "maximum credible earthquake," a magnitude 7.5 quake on the Teton fault. Since then various studies have cast doubt on this belief.O'Connell, D. R.; Graves, R. W.; Block, L. V

Strong Motion Prediction Within a Basin Located Above the Teton Fault in Wyoming

Dam facts and figures

The dam is owned and operated by the U.S. Bureau of Reclamation, which maintains the water level above the lake's natural elevation for downstream irrigation. *Type: Concrete gravity dam with earthen embankment wings *Drainage area: *Lake elevation: **Normal full pool: **Maximum pool: **Minimum pool: **Maximum water surface: *Usable storage (6730–6760 ft): *Crest elevation: *Crest length: *Crest width: *Base width: *Structural height: Image:USBR Jackson Lake Dam 1.jpg, Jackson Lake Dam. View is to the west. Image:USBR Jackson Lake Dam 2.jpg, Jackson Lake Dam. View is to the northwest.

References

External links

U.S. Bureau of Reclamation: Jackson Lake Dam

* ttps://web.archive.org/web/20070701100807/http://www.nwd-wc.usace.army.mil/report/jck.htm U.S. Army Corps of Engineers: Jackson Lake Dam and Lake Hydrologic Data
U.S. National Park Service: The Snake River: Responses to Jackson Lake Dam
(PDF) ink expired {{Snake River Dams Dams in Wyoming Dams on the Snake River Buildings and structures in Teton County, Wyoming Minidoka Project United States Bureau of Reclamation dams Dams completed in 1916 Gravity dams 1916 establishments in Wyoming

History

Reinforcement

Dam facts and figures

See also

References

External links