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
Glen Canyon Dam Sea. After this catastrophe, California and Arizona began to call for a dam to control the tempestuous river. In 1922, six U.S. states signed the Colorado River Compact to officially allocate the flow of the Colorado River and its tributaries. Each half of the Colorado River Basin – the Upper Basin, comprising Colorado, New Mexico, Utah and Wyoming – and the Lower Basin, with California and Nevada – was allotted of water annually, and a treaty between the U.S. and Mexico was signed in 1944 allocating to Mexico. The third lower basin state, Arizona, did not ratify the Compact until