Island Park Dam

Island Park Dam
Island Park Dam is located in Idaho
Island Park Dam
Location of Island Park Dam in Idaho
LocationFremont County, Idaho, near Island Park, Idaho
Coordinates44°25′06.92″N 111°23′47.50″W / 44.4185889°N 111.3965278°W / 44.4185889; -111.3965278
Construction began1937
Opening date1939
Operator(s)U.S. Bureau of Reclamation
Dam and spillways
Type of damZoned earthfill dam
ImpoundsHenrys Fork
Height94 ft (29 m)
Length9,500 ft (2,900 m)
Spillway typeUngated bathtub
Reservoir
CreatesIsland Park Reservoir
Total capacity135,205 acre-feet (0.166773 km3)
Catchment area482 sq mi (1,250 km2)[1]

Island Park Dam is operated by the U.S. Bureau of Reclamation in Fremont County, Idaho, United States. The dam lies in Targhee National Forest near Island Park. The zoned earthfill dam was built between 1937 and 1939 as part of the Minidoka Project, which provides water to irrigate farmland in Idaho's Snake River Plain.[1]

The dam provides only water storage, impounding 135,000 acre-feet (0.167 km3), which is distributed by the Cross Cut Canal to farms in Fremont and Madison counties in Idaho, and Teton County in Wyoming.[1] The Island Park and Grassy Lake reservoirs were built as an alternative to construction of a larger project that would have flooded the Falls River area of Yellowstone National Park.[2][3]

  1. ^ a b c "Island Park Dam". Bureau of Reclamation. Archived from the original on 26 September 2012. Retrieved 4 May 2011.
  2. ^ Haines, Aubrey L. (1996). The Yellowstone Story: A History of Our First National Park. University Press of Colorado. p. 346. ISBN 0-87081-390-0.
  3. ^ Yochim, Michael J. "Conservationists and the Battles to Keep Dams Out of Yellowstone: Hetch Hetchy Overturned" (PDF): 299. {{cite journal}}: Cite journal requires |journal= (help)