July 10 (Bloomberg) -- Lake Mead, the man-made reservoir that supplies 90 percent of the water for 2 million people in the Las Vegas area, has been reduced by drought to the lowest level since it was filled in 1937, according to the federal government.
The lake, now at 39 percent of capacity, has been dropping since 2012, according to U.S. Bureau of Reclamation data, as much of the western U.S. has suffered the most serious drought in decades. The shortfall is endangering water supplies to the residents and 43 million annual visitors to the driest metropolitan area in the country.
Lake Mead, created by Hoover Dam in 1936 and 1937, holds mountain snowmelt from the Colorado River for farms, homes and businesses predominately in southern Nevada, southern California and most of Arizona. No metropolitan area depends on the lake more than Las Vegas, which lacks groundwater or other local sources.
“This is significant because it’s a resource used by three states,” said Rose Davis, a spokeswoman for the bureau, which manages the supply. “We all have to keep an eye on it because it’s the major water source for three areas. It concerns us all very much.”
The lake’s surface, which reached a record high of 1,225 feet above sea level in July 1983, is now at about 1,083 feet, according to the bureau. If the level drops below 1,050 feet, one of the two intakes that feed water to Las Vegas will become inoperable. At 50 feet lower, the other would fail. Since 2008, contractors have been boring through rock to create a third conduit to draw water from as low as 860 feet.
About 55 percent of Nevada, already the nation’s driest state, is under “extreme” or “exceptional” drought conditions, the worst grades on the U.S. Drought Monitor, a federal website. Portions of California, New Mexico and Colorado also are in the “exceptional” category, according to the monitor.
Along the Las Vegas Strip, the fountains at the Bellagio Hotel and Casino still dance in sync with music every 15 minutes at night, with recycled water. Guests at various casinos still cool off from daytime temperatures of more than 100 degrees Fahrenheit (38 Celsius) in outdoor swimming pools. In suburban Henderson, residents of the Lake Las Vegas community still boat on a 320-acre lake formed by water diverted from the Colorado River.
Nevadans have cut back on water use since the magnitude of the drought became clear, according to data from the Southern Nevada Water Authority. The region reduced daily usage 4.6 percent per person, to 124 gallons in 2013, from 130 gallons in 2012, authority spokeswoman Nicole Lise said by e-mail. In Los Angeles, personal consumption in 2013 was 129 gallons, according to the Department of Water and Power.
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