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 Mexico Territory, and Nevada state. They remained the primary means of transportation of freight until the advent of the more economical railroads began cutting away at their business from 1878 when the first line entered Arizona Territory. Steamboats were tried on the upper Colorado River: in Glen Canyon; on the Green River in Utah and Wyoming; and on the Grand River, (renamed as the upper part of the Colorado River after 1921), above its confluence with the Green River in Utah and in Colorado. These attempts in the late 19th Century and early 20th Century met with little success. The