This educational video is about building the Hoover Dam and explains the construction, engineering, and design. Hoover Dam is big and is made of concrete, known in physics and engineering as an arch-gravity dam. The largest hydroelectric technology plant in the United States is at Grand Coulee Dam. Such a big concrete structure had never been built before, and some of designs and techniques were all but theory at the time. It’s located in the Black Canyon of the Colorado River, on the border between the U.S. states of Nevada and Arizona. It took 5 years to construct, between 1931 &1936 during the Great Depression. Its construction was the result of a massive effort of design, involving thousands of workers, and cost over one hundred lives at a financial building cost of $49 million. It gets its common name from President Herbert Hoover who commissioned the United States Federal Government project.