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
Lake Sakakawea Lake Sakakawea Lake Sakakawea is a large reservoir in the north central United States, impounded by Garrison Dam, a U.S. Army Corps of Engineers dam located in the Missouri River basin in central North Dakota. Named for the Shoshone-Hidatsa woman Sakakawea, it is the largest man-made lake in the State of North Dakota, the second largest in the United States by area after Lake Oahe, and the third largest in the United States by volume, after Lake Mead and Lake Powell. The lake is located about from the state capital of Bismarck; the distance by the Missouri River is about