Fort Peck Lake
Fort Peck Lake, or Lake Fort Peck, is a major reservoir in Montana, formed by the Fort Peck Dam on the Missouri River. The lake lies in the eastern prairie region of Montana approximately east of Great Falls and north of Billings, reaching into portions of six counties. 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, 300-foot wide navigation channel from Sioux City, Iowa, to the mouth of the Missouri just above St. Louis . Following severe flooding along the Missouri River in 1943, which hampered the economic development of the Missouri River Valley and damaged production of military supplies for then-ongoing World War II, five additional dams were added when the federal government adopted the Pick-Sloan Plan, calling for a series of dams and reservoirs to be built along the Missouri and its tributaries. 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. With a volume of when full, Fort  Peck is the fifth largest artificial lake in the United States. It extends through central Montana, and its twisting, inlet-studded shoreline has a total length of some . Along with the Missouri River, smaller tributaries such as the Musselshell River, Fourchette Creek, Timber Creek, Hell Creek and Dry Creek feed the reservoir; the latter forms the longest side arm of the reservoir, which reaches some southwards. The lake covers an area of , making it the largest in Montana by surface area, although Flathead Lake has a larger volume due to its greater depth. The reservoir is also a tourist attraction , with 27 designated recreational sites bordering its shores. Bordering nearly the entire reservoir is the Charles M. Russell National Wildlife Refuge, which has preserved much of the high prairie and hill country around the lake. The lake is featured in the film Jurassic Park III, as part of an excavation.