Hoover Dam construction

In the early 20th century, the lower region of the Colorado River was considered as a site for flood control and a potential source of hydroelectric power for the growing demands of western US states. What would be known as the Hoover Dam was authorised by President Calvin Coolidge in 1928, and construction began by building conglomerate Six Companies in March 1931. At the time the Hoover Dam was the largest in the world, requiring over 3.3 million cubic metres of concrete to build the structure, including the power station.