A MARTÍNEZ, HOST:
All right. California's run of intense winter weather is not over.
STEVE INSKEEP, HOST:
The first of two atmospheric rivers is hitting the state today. Somewhere over the head of A Martínez, there's a high risk of flooding and landslides and avalanches. And Governor Gavin Newsom wants President Biden to declare an emergency and release federal aid.
MARTÍNEZ: NPR's Nathan Rott is in Southern California. Nathan, before I drove in to NPR West, the skies looked like they were about to tear open at any moment. It looks like it could be a pretty big storm.
NATHAN ROTT, BYLINE: Yeah, it definitely is. You know, we're talking about forecasts of more than 100 inches of snow at some mountain passes in the Sierra Nevada, upwards of 10 inches of rain in some parts of central California. It'll be a little tamer down here in southern California. But millions of people were put under flood watches Thursday in anticipation of this atmospheric river that's expected to really hit home today - atmospheric rivers being essentially giant conveyor belts of moisture that cart water from the tropics to places like California. This one is carrying water from near Hawaii. And what's unique about this storm and concerning is that it's expected to bring rain to areas that have already been inundated with snow.
MARTÍNEZ: Yeah, there are some mountain communities that are still trying to dig themselves out.
ROTT: Yeah, that's right. I mean, places like Big Bear, not far from where both of us are, which has been dealing with blocked roads and power outages from that deep snow, but even more so in central parts of the state. You know, the concern there is, A, that rain could fall at pretty high elevations onto some of these places that already are buried in snow. And so the problem that that could cause is this rain could be absorbed by the snow. And as any experienced driveway shoveler knows, wet snow is a heck of a lot heavier than dry. So it could add extra stress to structures that are still buried or trigger avalanches.
The other problem is potential runoff. Rain and warmer temperatures could help melt more of the snow, adding to these flood concerns. Here's Karla Nemeth, the director of California's Department of Water Resources, at a briefing yesterday.
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KARLA NEMETH: Rivers and creeks can rise very quickly, and so it does have the potential to be a dangerous situation, particularly in areas that had experienced flooding before.
ROTT: Which, if you remember, A, is a whole lot of California, as we've been seeing this year.
MARTÍNEZ: Yeah. So what are officials trying to do to lower those risks?
ROTT: So they're urging everyone who's experienced flooding this year, particularly those who live near a river or creek, to be ready to go, right? The U.S. Bureau of Reclamation and California's Department of Water Resources have been strategically releasing water from reservoirs so that they can handle all of this incoming runoff, which is a kind of wild thing because just last year nearly all of California was in some state of drought, so letting go of water would have seemed unthinkable.
MARTÍNEZ: All right. So you mentioned the D-word, Nate. Anytime it rains in California, people want to know, is the drought over?
ROTT: I'm sorry, A, it is not. Groundwater reservoirs in much of California are still very much depleted. Remember, people sucked so much water out of the earth in some parts of California during the heart of the drought that the ground actually sank. More broadly, though, if we step back, the megadrought plaguing California is also impacting much of the western U.S., and California depends on a lot of water from that broader region. So the good news is many parts of the West are seeing a wet year. Skiers are having a heyday.
But this drought has brought to light some bigger fundamental issues about water in the western U.S. - the way that it's used, the way that it's allocated, issues like the whole system being predicated on a presumption that there's more water available than there normally is. And even a really wet winter like we're experiencing right now - it does not address all of those concerns.
MARTÍNEZ: That's NPR's Nathan Rott reporting from southern California. Nathan, stay dry.
ROTT: You as well, A. Transcript provided by NPR, Copyright NPR.
