Beneath
California Crops, Groundwater Crisis Grows
5
April, 2015
Even
as the worst
drought in decades ravages California,
and its cities face mandatory cuts in water use, millions of pounds
of thirsty crops like oranges, tomatoes and almonds continue to
stream out of the state and onto the nation’s grocery shelves.
California has pushed harder than any other state to adapt to a changing climate, but scientists warn that improving its management of precious groundwater supplies will shape whether it can continue to supply more than half the nation’s fruits and vegetables on a hotter planet.
As a drilling frenzy unfolds across the Central Valley, California’s agricultural heartland, the consequences of the overuse of groundwater are becoming plain to see.
In some places, water tables have dropped 50 feet or more in just a few years. With less underground water to buoy it, the land surface is sinking as much as a foot a year in spots, causing roads to buckle and bridges to crack. Shallow wells have run dry, depriving several poor communities of water.
Scientists say some of the underground water-storing formations so critical to California’s future — typically, saturated layers of sand or clay — are being permanently damaged by the excess pumping, and will never again store as much water as farmers are pulling out.
“Climate conditions have exposed our house of cards,” said Jay Famiglietti, a NASA scientist in Pasadena who studies water supplies in California and elsewhere. “The withdrawals far outstrip the replenishment. We can’t keep doing this.”
Cannon Michael, a farmer who grows tomatoes, melons and corn on 10,500 acres in the town of Los Banos, in the Central Valley, has high priority rights to surface water, which he inherited with his family’s land. But rampant groundwater pumping by farmers near him is causing some of the nearby land to sink, disturbing canals that would normally bring water his way.
“Now, water is going to have to flow uphill,” said Mr. Michael, who plans to fallow 2,300 acres this year.
In the midst of this water crisis, Gov. Jerry Brown and his legislative allies pulled off something of a political miracle last year, overcoming decades of resistance from the farm lobby to adopt the state’s first groundwater law with teeth. California, so far ahead of the country on other environmental issues, became the last state in the arid West to move toward serious limits on the use of its groundwater.
Last week, Mr. Brown imposed mandatory cuts in urban water use, the first ever. He exempted farmers, who already had to deal with huge reductions in surface water from the state’s irrigation works. Mr. Brown defended the decision on ABC’s “This Week” on Sunday, saying, “They’re providing most of the fruits and vegetables of America to a significant part of the world.”
In normal times, agriculture consumes roughly 80 percent of the surface water available for human use in California, and experts say the state’s water crisis will not be solved without a major contribution from farmers.
California’s greatest resource in dry times is not its surface reservoirs, though, but its groundwater, and scientists say the drought has made the need for better controls obvious. While courts have taken charge in a few areas and imposed pumping limits, groundwater in most of the state has been a resource anyone could grab.
Yet putting strict limits in place is expected to take years. The new law, which took effect Jan. 1, does not call for reaching sustainability until the 2040s.
Sustainability is vaguely defined in the statute, but in most basins will presumably mean a long-term balance between water going into the ground and water coming out. Scientists have no real idea if the groundwater supplies can last until the 2040s.
Draining the Central Valley
Eighty percent of the water used by humans in California goes to agriculture. The state’s Central Valley has 17 percent of the irrigated land in the United States and produces a quarter of the nation’s food. But growing that food takes more water than is available from rain and snow, even in wet years.Sources: California Department of Water Resources; NASA; U.S. Geological Survey; Public Policy Institute of California By Jonathan Corum, Josh Keller and Tim Wallace
“I wish we could do it faster,” Mark Cowin, director of California’s Department of Water Resources, said in an interview. “I wish we would have started decades ago.”
But Mr. Cowin noted that the state, after neglecting groundwater management for so long, had a lot of catching up to do. Years of bureaucratic reorganization and rule-drafting lie ahead. “This is the biggest game-changer of California water management of my generation,” Mr. Cowin said.
In the near term, as the drought wears on and the scramble for water intensifies, farmers are among the victims of the drilling frenzy, as well as among its beneficiaries.
Governor Brown's decree is a band-aid on a severed limb. We're still hemorrhaging water and even destroying ancient aquifers. Soon the real pain will come.
Growers with older, shallower wells are watching them go dry as neighbors drill deeper and suck the water table down. Pumping takes huge amounts of electricity to pull up deep water, and costs are rising. Some farmers are going into substantial debt to drill deeper wells, engaging in an arms race with their neighbors that they cannot afford to lose.
“You see the lack of regulation hurting the agricultural community as much as it hurts anybody else,” said Doug Obegi, a lawyer with the Natural Resources Defense Council in San Francisco.
Against this backdrop, water-thirsty crops like almonds are still being planted in some parts of the Central Valley to supply an insatiable global demand that is yielding high prices.
The land devoted to almond orchards in California has doubled in 20 years, to 860,000 acres. The industry has been working hard to improve its efficiency, but growing a single almond can still require as much as a gallon of California’s precious water.
The expansion of almonds, walnuts and other water-guzzling tree and vine crops has come under sharp criticism from some urban Californians. The groves make agriculture less flexible because the land cannot be idled in a drought without killing the trees.
Not even the strongest advocates of water management foresee a system in which California farmers are told what they can plant. As the new system evolves, though, the growers might well be given strict limits on how much groundwater they can pump, which could effectively rule out permanent crops like nuts and berries in some areas.
“We want to be careful in dealing with this drought not to go down the command-and-control route if we can avoid it,” said Daniel Sumner, professor of agricultural and resource economics at the University of California, Davis. “It interrupts the flexibility, the creativity and the resilience that people in agriculture have already been using to deal with severe water cutbacks.”
So far, the over-pumping of groundwater has helped farmers manage through three parched growing seasons.
They were forced to idle only about 5 percent of the state’s irrigated land last year, though the figure is likely to be higher in 2015. The farmers have directed water to the highest-value crops, cutting lesser crops like alfalfa.
They have bought and sold surface water among themselves, making the best use of the available supply, experts like Dr. Sumner say. And the farmers’ success at coping with the drought has meant relatively few layoffs of low-income farmworkers.
Still, costs are up and profits are down for many farmers and the thousands of small businesses that depend on them, spreading pain throughout the Central Valley and beyond. “It’s been a tough couple of years, and it’s just getting tougher in rural parts of California,” said Dave Kranz, a spokesman for the California Farm Bureau Federation, a growers’ organization.
Because groundwater has helped keep production up, replacing a large proportion of the surface water farmers have lost, the drought has not led to big price increases at the national level, even for crops that California dominates.
Once the drought ends, a growing population and a climate altered by human-caused global warming will continue to put California’s water system under stress, experts say. A major question is how to manage the groundwater to get Californians through dry years.
Meeting that goal may have as much to do with how surface water is managed as with how much is pumped from the ground.
Several California experts used the metaphor of a bank account to describe the state’s groundwater supply. Deposits need to be made in good times, they said, so that the water can be withdrawn in hard times.
Yet for decades, California farmers have been overdrawing many of the state’s water-holding formations — its aquifers — even in years when surface water for irrigation was plentiful, the equivalent of overdrawing a checking account.
That will need to change, the experts said, with pumping being limited or even prohibited in wet years so that the underground water supply can recharge. Some land may need to be flooded on purpose so the water can seep downward.
The need for groundwater recharge may ultimately limit how much water farmers can have from the surface irrigation system, even in flush years — the same way that deposits in a bank account limit how many fancy dinners one can eat. Yet in a state where irrigation rights have been zealously guarded for generations, such limitations may not go down easily.
“It would be silly to think you are not going to have any fights,” said Denise England, the water expert for Tulare County, toward the southern end of the Central Valley. She cited an aphorism of the West: “Whiskey’s for drinking, and water’s for fighting over.”
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