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
Beaver Dam State Park (Nevada) dam in 1961. After Schroeder Lake was washed out by flood in 2005, the reservoir was not rebuilt. In 2009, the reservoir was drained and Beaver Dam Wash was restored to its natural state. The park has picnicking facilities, campgrounds, trout fishing in beaver ponds and streams, and hiking trails. The Overlook Trail offers a 360° view of the park. Beaver Dam State Park (Nevada) Beaver Dam State Park is a public recreation area encompassing more than along Beaver Dam Wash in Lincoln County, Nevada. The state park is on the Nevada/Utah state line about east of the town of