In addition, Palisades Dam, a multipurpose reservoir on the Snake River, provides flood control regulation, recreation, power, and holdover storage during years of average or above average precipitation to Minidoka Project lands. Ririe Dam, constructed by the Corps of Engineers on Willow Creek, also provides flood control regulation on this Snake River tributary within the Minidoka Project area. A full water supply is furnished to 216,796 acres and a supplemental supply to 946,846 acres. Water from Palisades Reservoir on the Palisades Project is instrumental in helping meet the Minidoka Project water requirements. Much of the power developed on the project is used for pumping water to lands lying above the gravity canals and for pumping drainage water.
Power also is furnished to several small communities in the area.
The site is approximately 25 miles north-northwest of Moran, Wyoming, and 35 miles east of Ashton, Idaho. Construction of the dam was completed in 1939. The purpose of the dam is to provide supplemental irrigation water for lands in the Fremont-Madison Irrigation District, Idaho. The site of Grassy Lake Dam and reservoir was formerly occupied by Grassy Lake, which was a natural lake. At normal water surface elevation 7210 ft, the reservoir has a surface area of 310 acres and an active storage of 15,182 acre-feet.