[1] The dam and reservoir were built in the 1930s to enhance navigation on the Missouri River, supplying enough water downstream of the dam to provide for a 9-foot deep (2.7 m), 300-foot wide (91 m) navigation channel from Sioux City, Iowa, to the mouth of the Missouri just above St.

[4] Fort Peck Dam was built from 1933 to 1940 by the U.S. Army Corps of Engineers; water impoundment began in 1937 and the reservoir was first filled to capacity in 1947.

[5] The federal government forced out ranchers and farmers who lived in the valley bottom to prepare room for the lake.

[6] With a volume of 18,700,000 acre-feet (23.1 km3) when full, Fort Peck is the fifth largest artificial lake in the United States.

[10] Bordering nearly the entire reservoir is the 1,719-square-mile (4,450 km2) Charles M. Russell National Wildlife Refuge, which has preserved much of the high prairie and hill country around the lake.