Oahe Dam Oahe Dam The Oahe Dam is a large earthen dam on the Missouri River, just north of Pierre, South Dakota, United States. The dam creates Lake Oahe, the fourth largest man-made reservoir in the United States. The reservoir stretches up the course of the Missouri to Bismarck, North Dakota. The dam's power plant provides electricity for much of the north-central United States. It is named for the Oahe Indian Mission established among the Lakota Sioux in 1874. The project provides flood control, Hydropower generation, irrigation, and navigation benefits. Oahe Dam is one of six Missouri River mainstem dams, the next
Elwha Dam 20 years for the river to fully return to its pre-dam conditions. The ultimate goal of the dam removal is restoring the river to a nearly pristine state. Elwha Dam The Elwha Dam was a 108-ft (33 m) high dam located in the United States, in the state of Washington, on the Elwha River approximately upstream from the mouth of the river on the Strait of Juan de Fuca. The Elwha River Ecosystem and Fisheries Restoration Act of 1992 authorized the US Federal Government to acquire the Elwha Dam and Glines Canyon Dam hydroelectric power projects for decommissioning and demolition