Oahe Downstream Recreation Area Oahe Downstream Recreation Area Oahe Downstream Recreation Area is a state recreation area in Stanley County, South Dakota in the United States. The recreation area is named for being immediately downstream of the Oahe Dam and Lake Oahe, a U.S. Army Corps of Engineers dam and reservoir. The recreation area is located along the Missouri River and is popular for camping, fishing and other water-based recreation. The area is located about 7 miles upstream of Pierre - the state capitol. The recreation area was constructed by the U.S. Army Corps of Engineers following construction of Oahe Dam, and legislation passed
Perunchani Dam of the reservoir. The dam is located about from Nagercoil, the administrative headquarters-town of Kanyakumari District, and about from the town of Kulasekharam. The average annual rainfall in the catchment is , and the average annual yield at the dam site is . The dam was constructed between 1948–1953 by the then State of Travancore-Cochin. The height of the straight gravity masonry dam above the deepest foundation is , with Full Reservoir Level (FRL) at , which is also the Maximum Water Level (MWL). The dam is long. The gross storage capacity of the reservoir is at the FRL, which