This is the south fork of the Flathead River, one of three forks of the Flathead about 98 miles long beginning in the Bob Marshall Wilderness.

The dam creates a large reservoir by withholding water in times of heavy runoff to minimize downstream flooding. This stored water is released for power generation when the natural flow of the river is low.
Downstream power benefits are of major importance since more than five times as much power can be produced from water releases downstream than is produced at Hungry Horse.