The Hoover Dam was built between 1931 and 1936 on the border between Arizona, Nevada, and California. It is 221 meters high and 201 meters thick at ground level. The concrete arch-gravity construction dammed the Colorado River and created Lake Mead, the biggest water reservoir in the United States. The main purpose of the dam was to control water flows. Before its construction, periodically occurring floods and seasonal dryness concerned the population in the southwestern states, whose livelihoods depended on agriculture. Along with inundation protection and improved irrigation possibilities, the third major asset of the Hoover Dam became the generation of energy. Multiple generators driven by turbines produced the electricity the fast-growing cities in Nevada and southern California urgently needed. But the dam also caused environmental concerns. In particular, it changed the Colorado River’s course, affecting fish habitats, sediment structures, water quality, and the capacity of the initial floodplains.
- Hiltzik, Michael A. Colossus: Hoover Dam and the Making of the American Century. New York: Free Press, 2010.