Kokosing Dam was built by the U.S. Army Corps of Engineers for flood control, recreation and wildlife management. The lake was created by impounding the headwaters of the north branch of the Kokosing River for flood control purposes on the Upper Muskingum River Watershed. Construction began in June 1970 and was completed in May 1972. The dam has an impervious, waterproof, core with earth-fill and rip-rap rock covering.