Heavy Rainfall Strains One Of California's Most Essential Reservoirs

Snow surveyors are measuring the health of the snow pack in the high altitude Sierra Nevada. After years of drought, much of the state is now experiencing one of its wettest years on record.

ROBERT SIEGEL, HOST:

Years of historic drought in California have given way to the wettest winter on record. At a snow measuring station high in the Sierra Nevada today, state surveyors reported that the snowpack is close to 180 percent of average. NPR's Kirk Siegler joins us now from that station. Hiya, Kirk.

KIRK SIEGLER, BYLINE: Hello, Robert.

SIEGEL: And first, tell us about the station up in the mountains. What's it like? And what have you just seen as that measurement took place?

SIEGLER: Well, I'm standing at this station in a meadow at about 7,000 feet in the Sierra Nevada. And I'm actually standing on probably more than eight feet of snow. And it's really, I've got to say, just extraordinary being here. I've been coming out here for this survey for - around this time of year - for the last three years. And a couple years ago, there was virtually no snow in this field. Last year, there was quite a bit. And this year, it is what state snow surveyors are calling a phenomenal snowpack.

We just watched California's Chief of Snow Surveys Frank Gehrke doing his manual measurements in the snow course here. He said that it's going to bode very well for water users downstream at just about 180 percent of average for this time of year.

SIEGEL: Now, Kirk, you mentioned users downstream. Tens of millions of Californians depend on snowmelt for water. So what does this one measurement today mean for them?

SIEGLER: This is huge, Robert. About a third of all of California's water comes from the snowmelt in the Sierra. This is the nation's biggest state. It's the biggest economy in the country. And the snow that I'm standing on, I guess you could say, holds quite a bit of currency. Many farmers downstream expect to get way more irrigation water than they had during the last four or five years of drought, when some of them got none. But I should say there's a catch.

Most of California's reservoirs are already at or near capacity. We've been reporting on the crisis at the Oroville Dam. The state's infrastructure is quite taxed. And winter, you know, is not even over yet. We could get a lot more snow. So the big question looming up here is what's going to happen when all of this melts? And if we were to get a big warm up, all of this is going to come down. So there's some concern here to temper, I guess, the good news.

SIEGEL: Yes. I mean, you can't just throw up reservoirs in a couple of weeks' notice. How is California's infrastructure able to handle such a melt, if there is one?

SIEGLER: Well, that's the big question. And really the only answer I can give you after talking to numerous water managers and experts in the last few days, it's really already getting tested, that infrastructure. And it's going to get more serious as spring approaches. You've got to understand that the infrastructure in California and these Western states that rely on snow-fed reservoirs was set up a long time ago, and when the climate and the population needs were different. And it needs to be adapted.

So there's a lot of debate going on about whether the current system can handle all of this record snow or near-record snow coming after a near-record dry period. That said, you know, California is used to extremes. And water managers say they'll be ready.

SIEGEL: But does a snowpack that's 180 percent of average, does that mean that California's drought is now over?

SIEGLER: You know, looking around me, Robert, it'd be hard to say standing here in this snowfield that we're still in a drought. Now, there are some places in Southern California that are officially still in drought according to the U.S. government. But Governor Jerry Brown has indicated he may lift the drought restrictions soon that have been in place since - by the way, he put those in place three years ago, standing in this very same field that I'm in that was at that time completely bare.

I think the trick here is how do you craft policy going forward to ensure that Californians don't get complacent? Because everyone here agrees that we could be right back into a severe drought as soon as next year.

SIEGEL: That's NPR's Kirk Siegler from a snowpack measuring station near Lake Tahoe in the Sierra Nevada. Kirk, thanks.

SIEGLER: Thank you, Robert.

(SOUNDBITE OF FOUR TET SONG, "CIRCLING")

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