Lake Mead, the nation's largest reservoir and water supply to much of the southwest, is rising for the first time in more than a decade. Ample snowfall this past winter in Wyoming, Colorado, and Utah is melting into the Colorado River, which, thanks to Lake Mead's Hoover dam, is the water source for nearly 30 million people in California, Arizona, and Nevada. "When we woke up on September 1, 2010, a very short time ago, we were looking at the very real probability that we could have some shortages," said John Entsminger, assistant general manager of the Southern Nevada Water Authority. While optimistic, he added that this is one year in a string of 12 extremely bad years. "I guess to put this entire thing in perspective: By the end of this calendar year, with the lake coming up as much as it will, Lake Mead will be at 56 percent of capacity." Although some studies have shown that per capita use of Colorado River water have decreased by an average of one percent per year from 1990 to 2008, the population of southwest cities like Phoenix and Las Vegas have increased, negating any savings. Still, water management authorities are optimistic: the reservoir is half full.
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