 Lake Mead and downstream releases from the dam also provide water for both municipal and irrigation uses . Water released from the Hoover Dam eventually reaches several canals . The Colorado River <unk> and Central Arizona Project branch off Lake <unk> while the All @-@ American Canal is supplied by the Imperial Dam . In total , water from the Lake Mead serves 18 million people in Arizona , Nevada and California and supplies the irrigation of over 1 @,@ 000 @,@ 000 acres ( 400 @,@ 000 ha ) of land . 
