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 (Illinois) Beaver Dam State Park (Illinois) Beaver Dam State Park is an Illinois state park on in Macoupin County, Illinois in the United States. The park is southwest of Carlinville, Illinois and is managed by the Illinois Department of Natural Resources (IDNR) as a public place for fishing. The state park centers on the Beaver Dam Lake, an artificial reservoir which was created by a private Carlinville fishing club in the 1890s. The club later became a private resort which catered to visitors who arrived via the adjacent Chicago and Alton Railroad. During the Great Depression, the resort failed. The state