ROBERT SIEGEL, HOST:
In California, water managers are running low on time. Areas of the Sierra Nevada are reporting up to 20 feet of snow, meaning the spring melt and runoff will be extraordinary. As NPR's Kirk Siegler reports, there are worries about an already-stressed water system handling even more.
KIRK SIEGLER, BYLINE: Near the headwaters of the American River, California's chief of snow surveys, Frank Gehrke, hoists a long, metal probe pole into the deep snow. He's measuring its depth and moisture content.
FRANK GEHRKE: Sixty-seven for 7A.
SIEGLER: Snowmelt from the Sierra Nevada accounts for a third of all of California's water. And Gehrke's findings aren't exactly breaking news. There is a lot of snow, 9 feet in this meadow and much more above us on the granite peaks of the Sierra Nevada.
GEHRKE: You know, the snowpack is a wonderful boon. But the - you know, the rain and the precipitation down below have certainly caused some issues...
SIEGLER: That pretty well sums up the mood across California right now, as the historic five-year drought recedes with a vengeance. All this snow is exciting, but there's anxiety, too. What's going to happen when it all melts? Already, rivers are raging.
(SOUNDBITE OF RIVER RUNNING)
SIEGLER: In the Central Valley, which is greener than it's been in decades, counties have declared states of emergency. Crews are racing to repair the spillway at the Oroville Dam, and statewide, Governor Jerry Brown says billions of dollars are needed to upgrade infrastructure.
(SOUNDBITE OF ARCHIVED RECORDING)
JERRY BROWN: These recent storms have had a real impact. We've got dam spillways eroding. We've got roads crumbling. We have our aging infrastructure, and it's maxed out.
SIEGLER: Now in the midst of one of the wettest years on record, reservoirs are at or near capacity. Near the Oregon border in the shadow of the massive snow-covered Mount Shasta is the state's largest reservoir. It was here just a few days ago the water got within 5 feet of the top of the 600-foot-high Shasta Dam.
DON BADER: Listen what happens as I peer over the edge of the spillway gates. Listen to this roar.
(SOUNDBITE OF WATER RUNNING)
BADER: You're watching right now 40,000 cfs, cubic feet per second, down the spillway, which is a lot of flow.
SIEGLER: That's about 18 million gallons a minute. Don Bader, the dam's manager with the U.S. Bureau of Reclamation, says they've been doing this type of flood control for weeks to make sure the dam doesn't overflow.
BADER: Basically, we're doing day-to-day monitoring, decision-making. So it was - it was just to get ahead of that.
SIEGLER: Engineers are getting set to shut down these gates, taking advantage of a welcome reprieve in the storm cycle.
BADER: I feel real good right now, yes, because right now we're getting down to the levels in the reservoir that we can feel highly confident that if we do get some - some major storms coming through, we're ready for them.
SIEGLER: Bader sounds confident because California's water czars are accustomed to erratic swings in the climate. But this year is a test. Storms last month alone dropped 25 inches of rain on this reservoir.
BADER: Typically, we don't see flows anywhere near this magnitude, but, yeah. When we get up to this point, there's going to be some flooding.
SIEGLER: There is a lot at stake. Tens of thousands of people live along the Sacramento River downstream. The muddy river beneath the dam is swelling and surging in places. In one neighborhood in Redding, folks are already dealing with flooding.
Roads here are blocked with yellow police tape. There is a stench from mud, flood debris and garbage. Some businesses are flooded out. Aleta Bussard has kept her family's gift shop open. She says the neighbors are worried about the next few months.
ALETA BUSSARD: Some of them are panic-stricken. But, you know, we've been in business for 45 years. And we're just to the point, you know, you just got to deal with how life comes at you every day. And you can't stress about what you can't fix or what you can't prevent.
SIEGLER: Across the street from her shop, there are sandbags piled up around the Shasta County Sheriff's Office, preparations just in case.
Kirk Siegler, NPR News, Redding, Calif.
(SOUNDBITE OF BEST COAST SONG, "FEELING OK") Transcript provided by NPR, Copyright NPR.