History of the Grand Canyon area stretched along a 278-mile (447 km) segment of the Colorado River from the southern border of Glen Canyon National Recreation Area to the eastern boundary of Lake Mead National Recreation Area. Grand Canyon National Park was designated a World Heritage Site on October 24, 1979. In 1935, Hoover Dam started to impound Lake Mead south of the canyon. Conservationists lost a battle to save upstream Glen Canyon from becoming a reservoir. The Glen Canyon Dam was completed in 1966 to control flooding and to provide water and hydroelectric power. Seasonal variations of high flow and flooding in the spring and
Canyon Lake (Arizona) Canyon Lake (Arizona) Canyon Lake is one of four reservoirs that were formed by the damming of the Salt River in the U.S. state of Arizona. The lake was formed by the Mormon Flat Dam, which was completed in 1925 after two years of construction. Canyon Lake, with a surface area of , is the third and smallest of four lakes created along the Salt River. Two others, Apache Lake and Roosevelt Lake, are upstream. The fourth, Saguaro Lake, is downstream. Canyon Lake lies approximately up the Apache Trail from Apache Junction, Arizona and east of Phoenix. It is within