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California has been hit by a series of storms in recent weeks that's caused at least 20 deaths and lots of damage. But the wet weather out West is also responsible for a deep snowpack in the Rocky Mountains, which might be good for the Colorado River because the snow could boost depleted reservoirs. The thing is, it won't be enough to undo the impacts of a long-running drought. From member station KUNC, Alex Hager reports.
ALEX HAGER, BYLINE: The snow is snowing, the wind is blowing, and high in the mountains of Colorado, the ski slopes are getting busy.
BILL PHILLIPS: To be schmaltzy, it's heavenly. It's a heavenly day of skiing.
HAGER: Bill Phillips stands at the top of a lift at Snowmass Ski Area near Aspen, where the flakes are piling up.
PHILLIPS: It's a fabulous year. And we've had regular snow. It's not just huge dumps, but regular, really nice, powder, fluffy snow to ski in.
HAGER: All of that powder is crucial for the Colorado River. Two-thirds of its water starts as snow in Colorado. This year, with totals well above average, spring snowmelt could help refill lakes Powell and Mead, the nation's largest reservoirs.
But Brad Udall, a climate researcher at Colorado State University, cautions against getting too excited.
BRAD UDALL: Everybody is so eager to make an early call on this. And invariably, you'll get caught with your pants down if you think you know what's going to happen.
HAGER: The Colorado River Basin has experienced more than two decades of megadrought. Udall says climate change is making this whole region drier. And even with snow totals at 130% of average, it would take more than one year of deep powder to make a real dent.
UDALL: We would need five or six years at 150% snowpack to refill these reservoirs, and that is extremely unlikely.
HAGER: Udall says warmer temperatures have already cut into the amount of snow that melts into the Colorado River. Since 1970, temperatures in the region have gone up by 3 degrees Fahrenheit. And on top of that, abnormally dry soil soaks up water before it can reach the places where people divert and collect it.
UDALL: I mean, we need to continue to plan for the worst year. That's what we've seen the last 23 years. That's what these warming temperatures continue to tell us. We have to plan for the worst.
HAGER: But planning has gotten a lot harder lately. Cynthia Campbell knows this firsthand. She's a water management adviser with the city of Phoenix. The fifth largest city in the country gets more than a third of its water from the Colorado River. Lately, she's been keeping closer track of the high-altitude snow.
CYNTHIA CAMPBELL: Our worst-case scenario, from our perspective, is that we have to be in the habit of annually looking to the mountains to see, what is the precipitation?
HAGER: Campbell says reservoirs provide a buffer against the fluctuation of dry years and wet years. But with those reserves shrinking, cities around the Southwest can only plan a year at a time.
CAMPBELL: That's just not enough time to make changes that you would have to make. But that is where we are. And so in some ways we're living - is it the worst nightmare? Might be.
HAGER: Seven states use water from the Colorado River, including Colorado, Utah and California. They've struggled to reduce their demand, threatening water for crops and hydropower that supplies electricity to millions. States can't agree on a plan to significantly cut back on use, so big water users are trying to stretch the supplies they already have.
Adel Hagekhalil runs the Metropolitan Water District of Southern California, which stretches from north of Los Angeles all the way past San Diego.
ADEL HAGEKHALIL: One storm is not going to change the game. Whether we get a wet year or not, we need to continue to focus on building the infrastructure we need to create local water supply.
HAGER: Hagekhalil is talking about programs to reuse existing water - cleaning up sewage to make it drinkable, capturing stormwater and incentivizing cutbacks to home water use. That's all to help provide insurance for the 19 million people whose taps draw from this system.
HAGEKHALIL: We have to be ready, and it will be on us if we're going to take the right actions today to invest and build the necessary infrastructure.
HAGER: And as climate change keeps shrinking the snow that supplies water to people and farms across the Southwest, the need to adapt is only getting bigger.
For NPR News, I'm Alex Hager in Snowmass Village, Colo.
(SOUNDBITE OF STAN FOREBEE'S "RUBY HILL") Transcript provided by NPR, Copyright NPR.