A MARTINEZ, HOST:
Residents in Arizona, Nevada and across the border in Mexico will have to cut their water consumption starting next year. This the day after the extraordinary announcement by the U.S. government of a first-ever water shortage on the Colorado River. Here's NPR's Kirk Siegler.
KIRK SIEGLER, BYLINE: Some 40 million people and countless farms rely on the Colorado River and its tributaries. The shortage comes amidst a megadrought on the river basin that's so far lasted 22 years. And as desert cities like Las Vegas and Phoenix continue to grow at among the fastest rates in the U.S., the entire river reservoir system, including Lake Mead, with its alarming white bathtub rings, behind the Hoover Dam, is now at just 40% of capacity. Here's the Department of Interior secretary for water Tanya Trujillo.
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TANYA TRUJILLO: We are seeing the effects of climate change in the Colorado River basin through extended drought, extreme temperatures, expansive wildfires and, in some places, flooding and landslides. And now is the time to take action to respond to them.
SIEGLER: Arizona will be the hardest hit initially with these cuts, losing almost a fifth of its entire river allotment. For now, California will not see any cuts because its water rights are senior under century-old river laws.
This shortage is monumental, but it was also widely expected. Western water officials have been planning for this eventuality by ramping up conservation and water recycling. Tom Buschatzke directs Arizona's Department of Water Resources.
TOM BUSCHATZKE: This is a serious turn of events, but not a crisis.
SIEGLER: For now, most cities won't see water supplies cut, but farmers will. In Arizona, thousands of acres of fields are expected to go fallow. Ironically, the arid Southwest is a huge producer of water-intensive crops, like cotton and alfalfa. Water law experts like Mark Squillace at the University of Colorado say climate change will force this region to rethink how it uses its limited water so many people rely on.
MARK SQUILLACE: We can't handle any more stresses. We're looking at a pretty dire situation right now on the river.
SIEGLER: Squillace says climate change is drying out the soils and leading to rapid evaporation, even in near-average winters like this last one in the Rocky Mountains, where snowmelt feeds the river.
SQUILLACE: The dry soils are acting like a sponge, and they're soaking up a lot of water before that water can make it into the reservoirs. And that's likely to continue.
SIEGLER: And federal water managers warn the shortages, too, will continue and probably get more severe. They'll reassess whether more cuts are needed in the next year.
Kirk Siegler, NPR News.
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