Oahe Dam dam upstream is Garrison Dam, near Riverdale, North Dakota, and the next dam downstream is Big Bend Dam, near Fort Thompson, South Dakota. In September and October 1804, the Lewis and Clark Expedition passed through what is now Lake Oahe while exploring the Missouri River. Oahe Dam was authorized by the Flood Control Act of 1944, and construction by the United States Army Corps of Engineers began in 1948. The world’s first rock tunnel boring machine (TBM) was invented in 1952 by James S. Robbins for the Oahe Dam project, which marked the beginning of machines replacing human tunnelers. The
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