Recreation on Clark Canyon Reservoir and Barrett's Diversion Dam, located on the Beaverhead River south of Dillon, Montana, is managed by the Bureau of Reclamation. Clark Canyon Reservoir is the site of Camp Fortunate, one of the more significant spots along the Lewis and Clark Trail. It was at Camp Fortunate that the Lewis and Clark expedition met the Lemhi Shoshoni Tribe and Sacagawea was reunited with her people. The Lewis and Clark Expedition cached their canoes and a stash of suppliesat this location for the return trip. The Camp Fortunate Interpretive Site presents information about the Lewis and Clark campsite and about their journey. Clark County Reservoir, with 4,935 water surface acres, 4,388 land surface acres and 17 miles of shoreline, offers good fishing for rainbow and brown trout. Concrete boat ramps, picnic areas and picnic shelters are available. There are 9 campgrounds, including on RV-only lot, for a total of 96 campsites. The Cattail Marsh nature trail offers wildlife watching opportunities for seasonal waterfowl. Clark Canyon Dam and Barretts Diversion Dam are features of the East Bench Unit of the Pick-Sloan Missouri Basin Program.

Take I-15 south 11 miles from Dillon to Reservoir. Most campgrounds are on MT secondary route 324.