Drought in the West

Eric Holthaus has a Slate article about the Western drought:

A new study jointly released by NASA and the University of California at Irvine paints a shocking picture for the future of Western water. Using a satellite designed to track changes in groundwater, the research team found that the Colorado River basin— which supplies water to forty million people in seven states— lost sixteen cubic miles of freshwater in the last ten years. More than 75 percent of that loss came due to excessive groundwater pumping. It’s the first study to quantify just how big a role the overuse of groundwater plays in dwindling water resources out West. From Texas to California, the new research backs increasingly pressing efforts to limit groundwater pumping and renegotiate water rights in an era of global warming. "We don't know exactly how much groundwater we have left, so we don't know when we're going to run out," said Stephanie Castle of UCI, the study's lead author, in a press release. "This is a lot of water to lose. We thought that the picture could be pretty bad, but this was shocking."
Nowhere is the drop in the Colorado River more apparent than in Lake Mead, which, earlier this month, set a new all-time record low. To memorialize the event, photographer Ethan Miller set out to take a series of “after” photos to complement pictures he took in July of 2007. When you compare the two sets (above), the result is nothing short of stunning.
The massive body of water was created in 1936, after the construction of the Hoover Dam on the Colorado River. For decades, it was the largest manmade lake in the United States. No longer. (A lake that spans the Dakotas is now Number One, thanks to the West’s long-term drought.) As people continue to flock to the Southwestern cities of Las Vegas, Phoenix, and Tucson, and as farmers keep watering the desert, Lake Mead continues to plummet.
This year, thanks to a wetland rehabilitation project in Mexico, the Colorado briefly reached the Sea of Cortez again for the first time since the El Niño floods of 1998. Before humans started tampering with building massive dams on the Colorado, it did so every year.
In the last seven years, Lake Mead’s dwindling has accelerated. The lake is now just barely more than a thousand feet above sea level, slightly below its previous record low set in November of 2010.
The before images were taken when the lake level was 1,111 feet above sea level. Lake Mead hasn’t been officially full—1,221 feet above sea level—since 1983.
The massive intake towers on the Hoover Dam in Lake Mead straddle the Nevada/Arizona border, in this 2007/2014 before-and-after. Should the current drought continue, the Hoover Dam could lose the ability to generate electricity.
Thanks to an ongoing mega-drought, Lake Mead’s water level will continue to fall for the indefinite future. The joint NASA–UCI study implicates continued groundwater pumping in the rapid decline.
In a two-year forecast released earlier by the Bureau of Reclamation, which manages Lake Mead, the lake is expected to drop another twenty feet into record territory by the summer of 2016. Well before then, perhaps as soon as April of 2014, downstream water rationing will kick in, which has never happened before.
The scenarios only get worse from there. According to a New York Times interview with John Entsminger of the Southern Nevada Water Authority: “If Lake Mead goes below elevation 1,000, we lose any capacity to pump water to serve the municipal needs of seven in ten people in the state of Nevada.” City of Las Vegas, consider this your official warning.
As shocking as images of the desiccating lake are, Las Vegas is in no immediate danger of running out of water. As long as the new “third straw” intake— a more than eight-hundred-million-dollar project designed to drought-proof Las Vegas’ water supply— is completed in time, which will allow the city to suck water from Lake Mead down to the very last drop. In the meantime, Las Vegas and other Western cities have been storing treated Colorado River water in underground aquifers in preparation for eventual shortages. Las Vegas has banked about eighteen months’ worth of supply in this manner. Despite the city’s wasteful ways and nearly complete dependence on Lake Mead and the Colorado River, Las Vegas takes only a small fraction of the river’s total flow each year.
The bigger problem is, global warming is starting to tip the odds toward more frequent and severe drought in the Southwest, and the future doesn’t look too bright. That means that, in just twenty years, Lake Mead could reach so-called “dead pool” levels, an unusable state in which the Hoover Dam, that symbolic marvel of twentieth-century triumph of human ingenuity over nature would become obsolete, likely for good.
One NASA scientist and co-author of the study, Jay Famiglietti, said in a press release that the new research on overuse of groundwater could be the nail in the coffin for water out West. "Combined with declining snowpack and population growth, this will likely threaten the long-term ability of the basin to meet its water allocation commitments to the seven basin states and to Mexico."

Rico says that the East is getting more than it needs; the West is welcome to come get it... (And for those who don't believe in global warming, what are you gonna drink?)