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Water Resources


Water Resources
About 88 percent of Southern Nevada's water comes from Lake Mead, which is fed by the Colorado River. The remaining 12 percent comes from groundwater.

The Colorado River
The Colorado River system supplies water to Mexico and seven western states — Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming.

In 1922, the Colorado River Compact, also known as the Law
of the River, was created. The compact divided the Colorado River among the seven western states according to their population size. In 1944, the compact was amended to include an allocation designated for Mexico.

Lake Mead
Lake Mead is a giant reservoir filled with Colorado River water. The man-made lake formed in the 1930s after the completion of Hoover Dam, which sits in Black Canyon on the Nevada-Arizona border. It regulates the flow of water to prevent flooding during wet years and to provide adequate water during droughts. Lake Mead can store up to 26 million acre-feet of water.

Watch the Video
Learn what the Water Authority is doing to protect our groundwater. (8:34)

Groundwater is located below the surface of the earth and occurs naturally as a result of snowmelt and rainfall in the nearby mountains. In Southern Nevada, the primary users of groundwater are the Las Vegas Valley Water District and the City of North Las Vegas.

Groundwater comes from the principal or deep water aquifer (underground rock or sediment that is permeable and can conduct water) generally located from 200 to 1,500 feet below land surface. This drinking-water supply is protected by a layer of clay and fine-grained sediments throughout most of the Las Vegas Valley.