Lake Oahe Lake Oahe Lake Oahe (oh-WAH'-hee) is a large reservoir behind Oahe Dam on the Missouri River; it begins in central South Dakota and continues north into North Dakota in the United States. The lake has an area of and a maximum depth of . By volume, it is the fourth-largest reservoir in the US. Lake Oahe has a length of approximately and has a shoreline of . 51 recreation areas are located along Lake Oahe, and 1.5 million people visit the reservoir every year. The lake is named for the 1874 Oahe Indian Mission. Lake Oahe begins just north of
Conant Brook Dam Conant Brook Dam The Conant Brook Dam is located on Conant Brook in Monson, Massachusetts, about upstream from the confluence of Conant Brook and the Quaboag River. It is approximately east of Springfield, Massachusetts. Designed and constructed by the United States Army Corps of Engineers, this dam substantially reduces flooding along the Quaboag, Chicopee, and Connecticut rivers. Construction of the project began in 1964 with completion in 1966 at a cost of US$2,950,530. The Conant Brook Dam is located within the Chicopee River watershed and is part of the Connecticut River basin. Access to the site is available from State