Source: Darren Guenther, © used with permission
The Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Arizona and Nevada. It was constructed between 1931 and 1936 during the Great Depression.
Lake Mead is the lake created by the Hoover Dam. It is the largest water reservoir in the United States when it is full -- but it hasn't been full for a very long time. A 2008 paper in Water Resources Research states that at projected climate trends, there is a 50% chance that Lake Mead will be empty by 2021. You can see the white marks in the photo that show how full the lake used to be -- these white marks are known as "bathtub rings".
CLICK HERE to turn this photo into a jigsaw puzzle.
Close the puzzle window when you're done to return to this page.