Colorado River as 2 billion years. The of the river that flow through the Grand Canyon are largely encompassed by Grand Canyon National Park and are known for their difficult whitewater, separated by pools that reach up to in depth. At the lower end of Grand Canyon, the Colorado widens into Lake Mead, the largest reservoir in the continental United States, formed by Hoover Dam on the border of Arizona and Nevada. Situated southeast of metropolitan Las Vegas, the dam is an integral component for management of the Colorado River, controlling floods and storing water for farms and cities in the lower
Glen Canyon Dam the Colorado's major upper tributary, at Echo Park and Split Mountain. The 1956 Colorado River Storage Project Act authorized the purposes of "regulating the flow of the Colorado River, storing water for beneficial consumptive use, providing for reclamation of arid and semi-arid lands, providing flood control, and generating hydropower." The proposal for Glen Canyon Dam was most vocally supported by the state of Arizona, which wished to get Colorado River water to Phoenix and Tucson, located hundreds of miles away from the Colorado in the center of the state. Glen Canyon Dam would regulate river flow between Lee's Ferry and