Are there dams in Grand Canyon?
No, although several dams bordering the park have a profound effect on Grand Canyon. At the upper end of the Canyon, 15 river miles / 24 km above Lees Ferry, is Lake Powell, formed by the waters behind Glen Canyon Dam. At the lower end of the canyon is Lake Mead, formed by the waters behind Hoover Dam. The controlled release of water from Glen Canyon Dam at the upstream end affects the water that flows through Grand Canyon. Waters from Lake Mead flood the lower 40 miles / 64 km of Grand Canyon when the lake is full. Hoover Dam was completed in 1936. Glen Canyon Dam was completed in 1963.
