About the Show
It took five years to build. When completed in 1936, Hoover Dam was one of the world's largest hydroelectric facilities. Today, it generates 4 billion kilowatt-hours of energy a year, enough to serve 1.3 million people. An astonishing 660 feet thick at its base, the dam needs to be strong enough to store up to two years' worth of the Colorado River's average water flow.


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