Communities, largely home to low-income Latino residents, still have dry wells. Restoring groundwater takes decades, with costly, long-term replenishment projects — and ultimately, much less pumping.
By Alastair Bland, Cal Matters
The powerful storms that clobbered California for weeks in December and January dropped trillions of gallons of water, flooding many communities and farms. But throughout the state, the rains have done little to nourish the underground supplies that are critical sources of California’s drinking water.
Thousands of people in the San Joaquin Valley have seen their wells go dry after years of prolonged drought and overpumping of aquifers. And a two-week deluge — or even a wet winter — will not bring them relief.
Even in January, as California’s rivers flooded thousands of acres, state officials received reports of more than 30 well outages, adding to more than 5,000 dry residential wells reported statewide in the past decade.
“Just one wet year is nowhere near large enough to refill the amount of groundwater storage that we’ve lost, say, over the last 10 years or more,” said Jeanine Jones, a drought manager with the state Department of Water Resources.
Water from heavy rains can reach shallow groundwater basins in a matter of days, but in places where wells must pump from deep underground aquifers — like those in the San Joaquin Valley — this can take months. And even a season’s worth of storms is not usually enough to restore wells left high and dry by years of overdraft.
“Just one wet year is nowhere near large enough to refill the amount of groundwater storage that we’ve lost, say, over the last 10 years or more.”
Jeanine Jones, state Department of Water Resources
Restoring California’s groundwater is not as simple as waiting for rain and letting it seep into the ground. It requires detailed planning and scientific analysis of project sites, and uses tens of millions of dollars in state funds. Land has to be purchased or growers must be compensated for flooding their fields. And it also means that growers — and to a lesser extent, communities — must reduce the water they pump.
Graham Fogg, a UC Davis professor of hydrogeology, said the recent rainfall could substantially help minimally impacted areas, like much of the Sacramento basin, where groundwater tables are only 25 to 30 feet down. But it’s a far different story in the San Joaquin Valley, where the water table is 100 to 300 feet down, even 700 feet in some places.
“That’s where most of the dried-up wells have occurred,” Fogg said, “and that’s where it will take years, maybe decades, of not only managed aquifer recharge, but also reduced pumping from wells, to raise groundwater levels back to more appropriate elevations.”
According to state officials and other groundwater experts, most wells in the San Joaquin Valley have virtually no chance of recovering unless groundwater pumping is drastically curbed.
“I’ve seen about 2,000 wells go dry, and we don’t see wells recover on their own,” said Tami McVay, director of emergency services for Self-Help Enterprises, a San Joaquin Valley nonprofit that provides funding to residents who need new wells. “They sometimes recover for a couple of days, but then they go dry again.”
Groundwater is liquid gold
Groundwater is among California’s most precious natural resources, providing about 40% of the water consumed in most years. It is an inexpensive, local source in a state where many cities rely on imported water and rural towns have no other sources. And its importance is magnified in dry years, when reservoirs fed by rivers are depleted.
The San Joaquin Valley’s groundwater reserves have been relentlessly pumped by farmers for decades. Tens of millions of acre-feet have been pumped from the ground, causing the water table to steadily drop and thousands of wells to go dry.
A handful of communities, largely home to low-income Latino residents, have run out of water, forcing people to use bottled water for everything. The true scope of the problem, in fact, may be underestimated, since many dewatered wells are unreported.
East Porterville, Tooleville, Tombstone Territory, Fairmead, Lanare and Riverdale are just a few of the San Joaquin Valley communities that have been hit hard with dry wells.
“There’s so much political pressure to maintain the status quo, and to continue pumping, because it’s tied up with economic profits. And the end result is community members who can’t rely on their wells for safe water,” said Tien Tran, a policy advocate with the group Community Water Center, which advocates for water equity.
Almost a decade ago, California enacted a law that is supposed to protect groundwater reserves from overpumping. The Sustainable Groundwater Management Act requires local groundwater agencies to halt long-term depletion and achieve sustainability, defined by specific criteria. But the deadlines are almost 20 years away, and basins are still being overdrafted.
The San Joaquin Valley’s major groundwater basins are designated critically overdrafted by the California Department of Water Resources. A year ago, the agency rejected the region’s groundwater sustainability plans on the grounds that they inadequately considered the needs of residential wells, among other impacts.
Gov. Gavin Newsom’s water strategy released last August called for increasing groundwater recharge by an average of half a million acre-feet each year. On Jan. 13, state water agencies announced a program to expedite approval of recharge projects.
Department of Water Resources Director Karla Nemeth said the voluminous mountain snowpack dumped in January offers a prime opportunity, and a time-sensitive one, to recharge aquifers.
“We’ve got a heck of a lot of snow in the Central Sierra,” she said. “That snow is going to melt, and we want the local water districts to be positioned to capture some of that excess snowmelt and get it underground.”
The quest to store rainwater underground
Compelled in part by state law, and often supported by millions in state funds, some farmers and other land managers have dug large recharge basins to capture stormwater and allow it to sink. Cities design similar projects, and in recent months alone, they’ve put tens of thousands of acre-feet of water into underground storage.
While not enough on their own to reverse overdraft, these programs could serve as models for scaling up recharge efforts statewide.
In the Tulare Irrigation District, for instance, stormwater during high flows is diverted into 1,300 acres of ponds used to recharge groundwater. In addition, in a new program launched last year, farmers who sink water into their fields during storms can get it back later, during dry periods. General Manager Aaron Fukuda said it has motivated dozens of landowners to take part this winter. As of Feb. 3, the district was bringing in water at a rate of 1,500 acre-feet daily, mostly to be deposited in the ground.
“The actions our district took last year are paying dividends this year,” Fukuda said.
This article was first published at Cal Matters.
