The lake is created by the Yonah Dam, which is owned and operated by Georgia Power, and generates 22 megawatts. Lake Yonah is a residential lake with seventy-two vacation and permanent homes. After the Tugaloo River flows from Yonah through the lower dam, it continues to Lake Hartwell, and joins the Savannah River, which empties into the Atlantic Ocean. Another tributary to this great river is the Seneca River, which flows into it from South Carolina. Lake Yonah is also a source of fresh water for the town of Toccoa, which is approximately twenty miles away.