Hoover Dam
... One of the most important and the most beautiful western dams is a Hoover dam. The Hoover dam was built over sixty years ago, and it still stands today as one of the world’s most outstanding engineering achievements. Hoover dam was built for many reasons and one of them was to control the flow of water in droughts. In a drought, the holes in the dam can be closed, allowing water to collect in the Lake Mead behind the dam. ... When there is a lot of rain, which leads to flood, the holes in the dam are opened so the river won’t overflow. Also, Hoover dam was build for better irrigation of crops. ... Hoover dam provides hydroelectric power to California, Arizona, and Nevada, the dam helps meet the water needs of more that 18 million people in the growing cities of Las Vegas Los Angeles, San Diego, Phoenix, and Tucson.