History of the National Park Service and multi purpose river basin development programs like the Tennessee Valley Authority which began in the 1930s and spread to river valleys in all parts of the country after World War II. Lake Mead was the first National Recreation Area. The Boulder Canyon Project Act, passed in 1928, authorized the Bureau of Reclamation to construct Hoover Dam on the Colorado River. Work began in 1931 and the dam, highest in the Western Hemisphere, was completed in 1935. The next year, under provisions of an agreement with the Bureau of Reclamation, the National Park Service assumed responsibility for all recreational activities
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