Tappan Dam was incorporated by the Flood Control Act of 1939 into the comprehensive plan of the Corps of Engineers, U.S. Army, to alleviate floods in the Ohio River Basin. Since August 1939, the Corps of Engineers, U.S. Army has operated and maintained the dam for flood control. Development of the reservoir area for public use and conservation continues as a function of the Muskingum Watershed Conservancy District.