Constructing the Hoover Dam

When it was originally built, the Hoover Dam was the largest concrete structure in the world. It weighs 6.6 million tons and stands 700 ft tall. The biggest challenge engineers faced while building the dam was the extreme heat. #ImpossibleEngineering Wednesdays 9/8 on Science http://www.sciencechannel.com/tv-shows/impossible-engineering/ Subscribe to Science Channel: http://bit.ly/SubscribeScience Check out SCI2 for infinitely awesome science videos. Every day. http://bit.ly/SCI2YT Download the TestTube app: http://testu.be/1ndmmMq