Lake Oahe Pierre, South Dakota and extends nearly as far north as Bismarck, North Dakota. Mobridge, South Dakota is located on the eastern shore of the central portion of the lake. Bridges over Lake Oahe include US Route 212 west of Gettysburg, South Dakota and US Route 12 at Mobridge. The former town of Forest City has been flooded beneath Lake Oahe, about 9 miles west of Gettysburg. Prehistoric archaeological sites have been explored in the area, including Molstad Village near Mobridge. It dates to before the emergence of the Arikara, Hidatsa and Mandan as separate peoples, and has been designated as
Diama Dam the riparian states within the Senegal River Basin Development Authority agreed to develop the Senegal River. The Diama Dam was to be constructed in conjunction with the Manantali Dam which was to be located further upstream in Mali. Construction on the Diama Dam began on 15 September 1981 and was completed on 12 August 1986. The Manantali Dam was completed in 1988. The Diama project was funded by a US$149.5 million loan from the African Development Bank. The main section of the dam with ship lock and spillway is long while a long embankment dam section extends north to the