An image of expelled water creating a rainbow mist over the Colorado River on the downstream side of Hoover Dam in Black Canyon. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image showing a river-level view of canyon blasting in Black Canyon at the site of Hoover Dam construction. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image of Hoover Dam's crest and a sailboat on Lake Mead, as seen from the Nevada upstream side of the dam. Note: Boulder Dam was officially renamed Hoover Dam in 1947.
Black and white image of a mud deposit at Hoover Dam. This site can be seen at mile 257, and a member of the survey crew displays a representative sample of one of the mud cubes formed to show the depth of the crevices. Note: Boulder Dam was officially renamed Hoover Dam in 1947.