Lake Mead is the largest reservoir in the United States. It is located on the Colorado River about 30 miles (48 km) southeast of Las Vegas, Nevada, in the states of Nevada and Arizona. Formed by water impounded by the Hoover Dam, it extends 112 miles (180 km) behind the dam, holding approximately 28.5 million-acre feet (35 km³) of water.

Lake Havasu is a large reservoir behind Parker Dam on the Colorado River, on the border between California and Arizona. Lake Havasu City sits on the lake's eastern shore. The lake has a capacity of 648,000 acre feet (799,000 dam³). The concrete arch dam was built by the United States Bureau of Reclamation between 1934 and 1938. The lake's primary ...