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
Steamboats of the Colorado River the Colorado Steam Navigation Company between Yuma and Needles. By the end of 1905 all the steamboats, "Cochan", "St. Vallier" and "Searchlight", were withdrawn down river to Yuma. Their places were taken by smaller gasoline powered boats, until they were in turn replaced by trucks. The remaining steamboats worked on irrigation projects on the lower part of the river and on repairing the 1904-1907 breach in the Alamo Canal, that directed the Colorado River into the Salton Sink and created the Salton Sea before it was repaired. The last project, the construction of the Laguna Dam ended steam navigation on