Lake Mead is a reservoir formed by the Hoover Dam on the Colorado River in the Southwestern United States. It is located in the states of Nevada and Arizona, 24 mi (39 km) east of Las Vegas. It is the largest reservoir in the US in terms of water capacity. Lake Mead provides water to the states of Arizona, California, and Nevada as well as some of Mexico, providing sustenance to nearly 20 million people and large areas of farmland.