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 reservoir has an available capacity of 619,400 acre feet (764,000,000 m3). The concrete arch dam was built by the United States Bureau of Reclamation between 1934 and 1938. The lake's primary purpose is to store water for pumping into two aqueducts. Prior to the dam construction, the area was home to the Mohave Indians. The lake was named (in 1939) after the Mojave word for blue. In the early 19th century, it was frequented by beaver trappers. Spaniards also began to mine the area along the river.