Fort Peck Dam is one of the largest hydraulically filled earth dams in the world, measuring 21,026 feet long, with a height of 250.5 feet. The five turbines can generate 185,250 kilowatts of power. Its original purpose was not only to control floods but to create jobs in a depression-saddled economy. In 1933, the undertaking was the nation's largest public works project. The building of the dam, at its peak in 1936, provided 10,456 jobs; it was completed in 1940.

The dam spans across the Missouri River from bluff to bluff covering 3.5 miles.

Fort Peck Lake is a Montana treasure for its size and outdoor opportunities. Fort Peck Lake has almost 1,600 miles of shoreline and is backed up for 134 miles behind the dam. The shoreline is equal to the total coastal front of the state of California. Six recreation areas within a few miles of the dam provide access for water sports, fishing and hunting. The Beaver Creek Nature Trail starts at the campground downstream from the dam and leads through wildlife habitat.