Hoover Dam

Hoover Dam plugs Black Canyon on the Colorado River, on the line between Nevada and Arizona. It was the largest project of its kind when it was built, and it still has a way of rearranging your sense of scale: the crest stands 726.4 feet (about 221 m) above the foundation rock, and the dam alone holds about 3.25 million cubic yards of concrete. The Bureau of Reclamation, the federal agency that built it, still operates it.

Work moved fast for the era. Contractors started in April 1931, poured the last concrete in May 1935 and had every feature finished by March 1, 1936, well ahead of the seven years allowed. Some 21,000 men worked on the project over its life, many of them living in Boulder City, a government town laid out for the purpose. President Franklin D. Roosevelt dedicated the dam on September 30, 1935.

The name has its own story. It honors Herbert Hoover, who as commerce secretary helped broker the Colorado River Compact. After Hoover left office, Interior Secretary Harold Ickes ordered in 1933 that it be called Boulder Dam, and the name stuck in common use until Congress restored 'Hoover Dam' in 1947. You will still see 'Boulder Dam' on older postcards and some signs.

The architecture rewards a slow walk across the top. Reclamation's first plans drew criticism as too plain, so the Los Angeles architect Gordon Kaufmann was brought in to rework the exteriors; he smoothed the intake towers, simplified the powerhouses and gave the whole project its streamlined Art Deco look. The artist Allen Tupper True designed the colored floor patterns inside, drawing on Native American geometric motifs, and on the Nevada side the sculptor Oskar J. W. Hansen created the monument of dedication: two bronze Winged Figures of the Republic flanking a tall flagpole, set in a terrazzo floor inlaid with a star chart meant to record the date of the dedication for anyone reading the sky far in the future.

Behind the dam lies Lake Mead, the reservoir it created; just downstream, the Mike O'Callaghan–Pat Tillman Memorial Bridge carries US 93 across the canyon. Before the bridge opened in 2010, highway traffic crossed on the dam's own crest.

Highlights