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 system supplies water to Mexico
and seven western states — Arizona, California, Colorado, Nevada,
New Mexico, Utah and Wyoming.
Learn about the Colorado River system.
Watch our Flash animation.
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 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
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.
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.