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The federal government has declared a water shortage for much of the Southwest. It's led to the first ever mandatory cutbacks for some who draw water from the Colorado River. Two decades of drought and climate change are cutting deep into the West's water supply. From member station KUNC, Alex Hager reports that the region is looking ahead to a future where that supply might keep dropping.
(SOUNDBITE OF WATER FLOWING)
ALEX HAGER, BYLINE: Water is rushing into a storage basin outside of Tucson, Ariz. Spilling out onto the cracked desert, the water held in this system is part of a crucial safety net that makes sure the city won't go dry. John Kmiec is Tucson's water director.
JOHN KMIEC: We're always banking about a third of our water from the Colorado River into the aquifer for future Tucsonans' use, while only using about two-thirds annually.
HAGER: On top of that, the city recycles and treats wastewater for park lawns and golf courses. It's all a defense against a grim reality. Twenty-two years of drought have left the west drier than ever. And the pool of usable water is shrinking. Already, Kmiec says, they've had to implement reuse and conservation efforts to accommodate a growing population.
KMIEC: Our total water demand in the Tucson area in 2020 is about the same as it was in 1990 but with about 200,000 more people living in our community.
HAGER: But those efforts will only get more important as levels in Lake Mead, a reservoir that supplies water to millions across the region, dropped further past already historic lows. Ted Cooke manages the Central Arizona Project.
TED COOKE: It is not a crisis, but it will become a crisis if we don't continue to pay attention and develop additional responses to the situation.
HAGER: Cooke runs a pipeline that pulls water from the Colorado River across 300 miles of desert to supply farmers and cities, like Tucson and Phoenix. The new cuts mean Arizona will lose about 8% of its total water supply. And forecasting data shows continued drought will probably mean even steeper cuts. Cooke says knowing that in advance is helpful.
COOKE: It doesn't make the news any less bad, but at least I can plan for it, and I can take what next step I can take.
HAGER: So far, the cutbacks are mostly slated to affect farmers starting in January. But Cooke says restrictions to municipal water supplies, affecting homes and businesses, could begin as soon as five years from now. But because of storage and conservation work, residents probably won't see the effects for even longer.
COOKE: We are not yet even close, I don't think, to the end of our road of saying, we don't have any more ideas. We're out of water, and we can't think of anything else to do. We are two decades away from that.
HAGER: But Cooke says that sense of security also hinges on the rollout of more aggressive conservation and new technology.
COOKE: The only way in two decades that we will reach that point is if we don't do any more starting today for that next 20 years.
HAGER: And that will be pivotal going forward because climate change is making it even harder to predict how much water the region will have to use.
JENNIFER PITT: Climate changes is water change. We can no longer rely on the fact that we know what the hydrology is going to be in the Colorado River basin, and that has water managers worried.
HAGER: Jennifer Pitt studies the Colorado River for the Audubon Society.
PITT: Water managers like to say hope for the best, but make sure you're prepared for the worst. And we can't even tell you with certainty what the worst could be.
HAGER: She says historically, the dry times were balanced out by wet years. But thanks to warmer temperatures and erratic climate patterns, that's no longer the case.
For NPR News, I'm Alex Hager. Transcript provided by NPR, Copyright NPR.