Farmers in California's drought-plagued Central Valley have big plans for the next year of heavy rains. They want to use that water to replenish depleted aquifers, akin to depositing water in a bank.

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In the heart of California, an area that's plagued by drought, farmers and water managers cannot wait for a year with lots of rain. Of course, the water is good for crops, but they also want to capture the water to store in natural aquifers. For people who rely on them, it could mean survival. NPR's Dan Charles has the story.

DAN CHARLES, BYLINE: There's a big patch of dirt behind Aaron Fukuda's office at the Tulare Irrigation District in California's Central Valley that he gets very excited about.

AARON FUKUDA: For a water resources nerd like myself, it's a sexy, sexy piece of infrastructure (laughter).

CHARLES: It's a 15-acre sunken field just sitting here surrounded by pistachio orchards and cornfields. It was built to capture a flood. California does get floods sometimes during the winter. Fukuda says, in the past, a lot of people just considered those winter floods a nuisance. But among people here who grow a lot of the country's vegetables and fruit and nuts, that attitude has changed completely.

FUKUDA: It's liquid gold. Cold, crisp flood water is gold these days.

CHARLES: When it starts raining and the rivers rise, Fukuda and his colleagues open some gates and send water surging through irrigation canals into a bunch of giant basins like this one.

FUKUDA: We fill everything up. This will be brimful.

CHARLES: So when it's full, how deep is the water?

FUKUDA: I think it's about 6 or 7 feet deep.

CHARLES: And then the water seeps slowly into the ground - eventually, all the way to the aquifer hundreds of feet below us. This is called a groundwater recharge basin.

FUKUDA: It really is the difference between our communities surviving and not.

CHARLES: That water has become precious because it's now a scarce and regulated asset. Farmers have pumped so much water from their wells over the years, the aquifers have become depleted. A new law just now taking effect will limit that pumping, which will hurt some farmers. But the law also says if people replenish the aquifer, like making deposits in an underground bank account, they'll be allowed to pump more out later when the dry years come. And farmers all over the Central Valley are grasping this idea like a lifeline. Jon Reiter, a rancher and water consultant, works with some of them.

JON REITER: I want to show you over here.

CHARLES: This is your friend's vineyard?

REITER: Yes, this is raisins.

CHARLES: The soil's sandy, looks like it would just suck up water. There's already an embankment around three sides of this field. It's almost a ready made basin for flood water.

REITER: But you can imagine how much water you could get stored into the ground in a location like this.

CHARLES: But he's growing raisins.

REITER: He is, and he's made the determination that he would be willing to actually remove the raisins.

CHARLES: The water he'd store here might be more valuable to him than the raisins he'd grow because it would earn him the right to pump more water from the aquifer during a future drought to irrigate some of his other fields.

REITER: It's like a savings account.

CHARLES: And another farmer half an hour southwest of Fresno may have the biggest groundwater ambitions of all. His name is Don Cameron. He's been worried about the aquifer for many years. Ten years ago, during a winter with lots of rain, he decided to use his irrigation setup to just flood some of his vineyards and orchards at a time when they didn't need water.

DON CAMERON: A lot of people were skeptical - our neighbors, especially. I mean, they thought we were crazy, that we were going to kill our vineyard.

CHARLES: But the grape vines and trees survived just fine, and water levels in the aquifer increased. Now, Cameron's persuading his neighbors to do the same thing on their farms, creating, in effect, a recharge basin that could cover tens of thousands of acres. All he needs is for Mother Nature to deliver a flood.

CAMERON: I know we'll have another one. There is no doubt in my mind we will flood again. And we may see more severe flooding in the future.

CHARLES: Climate experts agree. Warmer temperatures will mean less snow, but more rain in the Sierra Nevada mountains, so it will runoff and flood more quickly. And the biggest reservoir available to store it all is underground, that aquifer that California's farmers have been draining for most of the past century. Dan Charles, NPR News. Transcript provided by NPR, Copyright NPR.