Wirtz Dam (formerly Granite Shoals Dam) was constructed from 1949 to 1951 to provide hydroelectric power and to form Lake Lyndon B. Johnson (formerly Lake Granite Shoals), one of the Texas Highland Lakes. Lake LBJ ‒ as it is more commonly referred to ‒ provides cooling water for the Lower Colorado River Authority's Thomas C. Ferguson Power Plant along Horsehoe Bay. Wirtz Dam was originally named Granite Shoals Dam until 1951 when it was renamed in honor of Alvin J. Wirtz who had been instrumental in the formation of the LCRA.