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This Day in History: Construction Began on Hoover Dam

Summary: 
On July 7, 1930, construction began on Hoover Dam, a significant accomplishment for infrastructure and sustainable energy in America.

On July 7, 1930, construction began on the Hoover Dam. President Herbert Hoover was deeply devoted to protecting the environment, particularly focusing on pollution-free water, flood control, and fisheries. After a disastrous Mississippi River flood in 1927, Hoover recommitted to bettering American infrastructure to prevent another catastrophe.

Hoover Dam Workers

Before the Dam could be built the Colorado River had to be diverted through tunnels. This piece of equipment, named a Jumbo Rig, was designed to speed up the tunnel drilling process. Built on the back of a 10-ton truck, 24 to 30 drills could be operated at once. (Department of Interior Bureau of Reclamation)


“[Hoover] Dam will probably be the biggest dam, perhaps the biggest man-made thing in the whole wide world.”

— Fortune Magazine, September 1933


Hoover Dam Early Construction

Early construction in Black Canyon (Department of Interior Bureau of Reclamation)

Think of it as a giant Lego set, with over 200 blocks fitted together to stand 726 feet tall. The Hoover Dam has been called the Eighth Wonder of the World, comparable to the Great Pyramids of Egypt, and “a vision in the desert.”

In the 1940s, the Hoover Powerplant was the largest hydroelectric installation in the world. Today, over 1.3 million people benefit from the 4 billion kilowatt-hours of hydroelectric power the Dam generates each year.

Hoover Dam View from Crest

View from dam's crest during test of Jet Flow gates. (Department of Interior Bureau of Reclamation)

In addition to being an engineering masterpiece, controlling flooding and generating hydroelectric power, the Dam is a national gem, showcasing diverse artistry. Norwegian immigrant Oskar J.W. Hansen sculpted the Winged Figures of the Republic, a pair of 30-foot bronzed statues which guard the Nevada side of the Dam. Hansen stated that the sentinels symbolize "the immutable calm of intellectual resolution, and the enormous power of trained physical strength, equally enthroned in placid triumph of scientific accomplishment." The angels stand on a magnificent terrazzo floor patterned with a star chart from the 1935 date of dedication by President Franklin D. Roosevelt.


"The waters of this great river, instead of being wasted in the sea, will now be brought into use by man. Civilization advances with the practical application of knowledge in such structures as the one being built here in the pathway of one on the great rivers of the continent. The spread of its values in human happiness is beyond computation."

—Herbert Hoover, November 1932


Hoover Dam Jet Flow Gate Testing

Jet Flow Gate Testing, June 1998 (Department of Interior Bureau of Reclamation)

Hoover Dam was completed two years ahead of schedule and millions of dollars under budget. Over the years, investment in our nation’s infrastructure has fallen on the backburner, despite its importance for American citizens and our economy. The President has a plan to fix that, by reforming our programs and increasing funding to support our growing population and millions of jobs. It’s time to rebuild America.

President Obama at Hoover Dam

President Barack Obama views the Hoover Dam during a stop at the 1,900-foot long structure which spans the Colorado River at the Arizona-Nevada border, Oct. 2, 2012. (Official White House Photo by Pete Souza)