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The El Nino weather system is expected to bring heavy rain here in California, and that could be good, especially for farmers in the Central Valley who are hoping to capture some of the rain and save it for the future. Capital Public Radio's Amy Quinton reports.
AMY QUINTON, BYLINE: About 30 miles southwest of Fresno, giant machines are busy harvesting tomatoes on Don Cameron's 5,000-acre farm. It's fertile land even during the drought.
DON CAMERON: This area right here is not in a water district or an irrigation district. We've had to rely on well water for many, many years for all the time we've farmed this ground.
QUINTON: But over those years, the water level underground has dropped.
CAMERON: One of our wells, we've seen two-and-a-half foot of decline per year since 1986.
QUINTON: Now that California is in its fourth year of drought, ground water levels throughout the San Joaquin Valley are at record lows.
CAMERON: It looks like a desert. Everything's brown. Everything's dusty and dirty.
QUINTON: Cameron stands next to a busy highway overlooking the North Fork of the Kings River. It only has water in wet years when snow high in the Sierra melts and sends floodwater to fill the riverbanks. The last time that happened was 2012, and that's when Cameron took advantage of the extra water to flood his crops.
CAMERON: We put about 150 acres of wine grapes. We put water on those from January until May, for over five months, about six inches to a foot-and-a-half of water.
QUINTON: And that's way more water than his crops would ever need. But here's the idea. Cameron's grapes grow on sandy soils. If you flood those soils, water can seep quickly in the ground. Until now, restoring groundwater often required constructing big ponds on empty land to let water seep into the ground. Flooding crops could make millions of acres of land available to restore aquifers.
CAMERON: We actually did measurements, and we found that about 75 percent of the water that was applied was moving down to the groundwater.
QUINTON: You might think that much water would ruin his grapes, but it didn't.
CAMERON: I think we actually saw a little bump in production. After the water, it probably made the vines a little healthier to have the surface water put on them.
QUINTON: Cameron was able to use old flood irrigation piping and canals to move the floodwater. He is so convinced of the project's success, he's spending $2 million of his own money to expand it. He and more than a dozen nearby farmers plan to flood 16,000 acres. Philip Bachand is helping engineer the project. He says with climate change, California should rethink how it manages water.
PHILIP BACHAND: There's a big need to be able to capture this different kind of runoff if it happens. And the reality is, the reservoir system is probably not really capable of doing it.
QUINTON: Restoring ground water can't be done everywhere. Not all soils are permeable, and not all crops can tolerate extra water in the winter. But it shows enough promise to garner the attention of almond growers. The thirsty crop has been villainized in the drought. The Almond Board is funding a study with University of California, Davis to see if flooding orchards can work. Ken Shackle is working on the project.
KEN SHACKLE: Almonds, I think, are a very interesting test case because the almond acreage is huge, and a lot of them are in areas that are - the soils are good for groundwater recharge.
QUINTON: One drawback is that most almond growers no longer have the piping and canals once used to flood irrigate. But farmer Don Cameron says every effort should be made to see if it's possible to restore groundwater.
CAMERON: This is something that can be done now in a relatively short amount of time. And the benefit is immense. You're essentially putting money in the bank for a rainy day.
QUINTON: Or, in this case, for a dry day. State law will soon require local water agencies to have plans to manage groundwater sustainably. For NPR News, I'm Amy Quinton in Sacramento. Transcript provided by NPR, Copyright NPR.