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
Norris Dam State Park dam to the base of River Ridge at the Claiborne-Grainger county line. The lake also spans the lower of the Powell River from the river's mouth to a few miles south of Harrogate, and the lower of Cove Creek. The Norris Dam Reservation, which is managed by the Tennessee Valley Authority, consists of the area immediately around Norris Dam and immediately downstream from the dam on both sides of the Clinch. The western half of the reservation, which is largely undeveloped, is known as the River Bluff Small Wild Area. Norris Dam State Park consists of two sections along the