Special report: Aquifers shrink, nation digs deeper for water
Special report: Aquifers shrink, nation digs deeper for water
By Mike Lee
Saturday, August 4, 2012
Deep underground — far out of sight and out of mind for most people — dreams are turning to dust.
Few places in Southern California is that more evident than the desert sands of Borrego Springs, where residents, farmers and golf course operators are sucking about four times as much water from the ground each year as nature replaces.
They’ve been pumping so hard for so long that the community’s main aquifer could essentially run dry after a few more decades. That’s a dire possibility: A recent study showed it would be prohibitively expensive to build a pipeline to an outside source.
Dimming prospects have left residents scared and angry in a town whose name now seems ironic. Resident Ray Shindler fears the worst: “I think that this community is going to run out.”
Similar concerns are bubbling up along San Diego County’s backcountry and across the nation — particularly in places such as the Central Valley and the Great Plains, where residents have dug deep to withstand a drought that has squeezed the nation’s midsection dry.
“It took Mother Nature in some cases thousands of years to accumulate the water in the aquifers, but we are pumping it out in mere decades,” said Robert Glennon, a law professor and water expert at the University of Arizona. “It’s a huge national and international problem. … It is utterly unsustainable and scary.”
Groundwater is hard to manage and measure because it’s mostly invisible. It seeps into the earth from lakes, rain and other sources. Then, it collects in zones called aquifers where the soil becomes saturated to the point where it can support regular withdrawals or even spill water onto the surface. Historically, there have been few limits on wells, creating numerous spots where aquifers have been overtapped by a growing population relying on the same resource.
A 2010 study led by a researcher in the Netherlands said the rate at which global groundwater stocks are shrinking more than doubled between 1960 and 2000. And a more recent report by a U.S. Geological Survey scientist showed that groundwater depletion rates were relatively low before 1950, then spiraled upward starting in the 2000s.
Groundwater is often overlooked in San Diego County because more than 80 percent of local supplies are imported from the Colorado River and the Sacramento-San Joaquin Delta. Still, some 41,000 people in dozens of small communities across the county’s rural spine depend on wells because they live beyond the reach of the aqueducts.
Wells also buoy urban supplies in the South Bay, and San Diego city officials in June announced a test well project in the Golden Hill neighborhood as part of their strategy to find new water sources.
Troubles tracking and managing groundwater are daunting for San Diegans because climate science strongly suggests the Southwest will become hotter and drier in coming decades. The region’s main water source — the Colorado River — already has passed a tipping point and federal projections say the imbalance between supply and demand will to grow. By 2060, the river could be short by the equivalent of what it takes to serve 7 million homes a year.
And groundwater plays a critical role in the state’s overall water budget, accounting for about one-third of the total consumption in average years and much more in dry years. Take that away and competition for supplies will skyrocket along with prices.
Legislation and litigation have helped to curb the anything-goes approach, but it remains entrenched.
“In most places around the world, (groundwater) is neither monitored nor managed,” said James Famiglietti, director of the University of California Center for Hydrologic Modeling in Irvine. “In the U.S. if you own the land, you can pump as much groundwater as you want without having to report what you’ve taken. That’s a holdover from the frontier days when no one knew anything about how the Earth worked, and we still needed to carry guns to shoot bears.”
San Diego’s backcountry
Across the globe, groundwater is a godsend. The electricity needed to pump it from the depths can be costly, but in some places it possesses near-magical qualities: cheap, clean and abundant.
Of course, there are downsides: The interconnected nature of aquifers and surface water can lead to too many demands by farms and cities. In addition, salts and other minerals tend to increase with depth.
And, it’s difficult to pinpoint how much water is left in a given aquifer because it’s often more of an economic question than a scientific one. Wells can be deepened, but at some point the production is so limited, energy is so expensive and the water is so loaded with minerals that it’s not financially feasible to pump it.
California officials estimate 750,000 wells have been drilled in California and about 20,000 more are added each year. They are viewed essentially as a property right with few constraints, though several regions of the state have set rules to curb overuse.
“We don’t regulate groundwater withdrawals, so we don’t have numbers on groundwater extraction,” said Jennifer Iida, a spokeswoman for the state’s Department of Water Resources. “In general, landowners can drill a well and use as much water as they please for any beneficial use.”
The California Legislature in 2009 passed a law that established for the first time a coordinated effort by state and local water agencies to publicly report groundwater elevations. Still, analysis is years away.
San Diego County records show there are likely thousands of unpermitted wells in the backcountry, raising the potential for supply problems all along the rural-urban interface where reliance on groundwater is common.
Concerns have emerged in Poway’s Old Coach Estates, where well-water levels have dropped by more than 100 feet since April 2011, according to measurements collected every Saturday morning by a small contingent of residents.
Several of the neighborhood’s two dozen homes rely solely on groundwater, and others use wells mainly for irrigation. Many residents blame the nearby Maderas Golf Club, owned by Sunroad Enterprises, for sucking the earth dry.
“We basically wake up every day and hope we still have water,” said Jessica Owens, who lives about a half-mile from the golf course.
She said her property has two dry wells, including one from the early 1900s that was just 18 feet deep. The lone functioning well has no meter on it so she can’t monitor water levels, but she’s concerned about dramatic declines detailed in a May report commissioned by residents.
At Sunroad, vice president of development Tom Story said the company’s studies suggest that Old Coach residents are overdrafting their own wells. He said Maderas stopped pumping groundwater under Poway city orders about a year ago and watched the water levels in its wells rise while the Old Coach neighborhood wells kept falling — a sign to him that there’s no direct connection.
“I know that a big green golf course provides an easy target,” Story said. “If there was any evidence that our operations were impacting the neighbors, we would be working with them to address the issue. But there’s not.”
When settlers arrived in Southern California, groundwater was so common that several spots were named for abundant sources — Fountain Valley, Borrego Springs, Artesia and so on. Early San Diegans relied so heavily on groundwater that many local aquifers were dangerously depleted before construction of a pipeline from the Colorado River in the 1940s.
At the U.S. Geological Survey in San Diego, recent explorations by Wes Danskin have turned up enough groundwater to serve roughly 40,000 homes a year mostly in the South Bay.
“It will be helpful but not allow us to stop importing water,” Danskin said.
Residents of Borrego Springs don’t have the option of relying on imported water because they aren’t connected to outside sources via aqueducts. Homeowners, golf courses and farmers in the desert town are tapping the region’s aquifer system about four times faster than it refills.
Geologists say Borrego’s groundwater basin was last full about 1945, and since then water levels appear to have spiraled down by as much as 180 feet in places. “For most of the valley, groundwater levels are declining year after year, decade after decade,” said Tim Ross, a senior scientist for the state Department of Water Resources. “The historical springs in Borrego Valley are all dry.”
If water use continues unabated, models suggest Borrego Springs could practically empty its largest, cleanest aquifer in 50 years and be left with increasingly poor-quality and expensive water.
Crafting a sustainable future would require incredibly strict water diets: One possible survival strategy is for golf courses and farms to reduce use by 80 percent and residents to cut back by 48 percent — an unlikely scenario.
Borrego Water District officials can encourage conservation, but they can’t force farmers or golf courses with their own wells to cut back even though those groups use an estimated 90 percent of the water. So, the agency has proposed a cooperative groundwater management program for the basin even though entrenched interests suggest that will be difficult to achieve.
Los Angeles lawyers who represent Borrego growers say the district’s efforts have been marked more by demands than cooperation, making litigation more likely.
“For those (residents) who think the great solution is just to force all the farmers out or eliminate agriculture in this area, all you are doing is making a lot of lawyers happier because there will be such a battle,” farmers’ attorney Malissa McKeith said during a town-hall meeting in March. “In our state, we have property rights, and we have the rule of law.”
At an intersection among nut trees in the Central Valley, two crumbling buildings stand as a memorial to what can happen when so much groundwater is pumped that the land sinks unevenly and tears apart whatever is on top.
The deserted outpost is the legacy of a dilemma that was thought to be effectively addressed by the 1970s with the arrival of canals that diverted river water onto some of the world’s best farmland and reduced reliance on wells.
Almost everyone lost track of the problem — known as land “subsidence” — since then, but it turns out that it didn’t really disappear, said Michelle Sneed of the USGS as she pulled her Jeep onto a levy road 25 miles north of the dilapidated buildings.
Every so often, she’d stop to point out giant slabs of buckled concrete in the canal walls she attributes to falling water levels underground that allow the earth to sink as it compacts. Settling not only threatens the local water distribution system but the canals that deliver it to Southern California.
“The scale of this thing is huge,” said Sneed, who recently restarted dormant federal studies to track how fast the valley’s land is giving way. “So many times, people don’t realize what this is. There is a disconnect: A farmer that’s having a problem with a particular well, or with a section of canal, may not realize that the problem is regional.”
To Sneed’s trained eye, the valley is dotted with clues that residents and farmers have removed what one recent study estimates to be roughly the volume of Lake Mead between 2006 and 2009 as drought hit and river water deliveries shrank. About 20 percent of all the groundwater pumping in the nation is from Central Valley soils. The southern section is by far the worst off and some experts have warned that the region may essentially run out of groundwater in a matter of decades, despite management efforts.
Sneed’s predecessors first noticed subsidence problems in the 1930s, then started studies in the 1950s out of concern for the integrity of major canals. “Farmers used to sit on their porch and say, ‘I used to see the mailman coming. I can’t see him anymore” because the land has fallen so much, she said.
Below ground, the dynamic is relatively simple: Soils deflate as groundwater is removed. Grains of clay that were propped up by water pressure flatten together like a stack of pancakes when the liquid is removed, taking up less space. If everything sinks at the same rate, there are few problems. “But when you start putting holes in places with canals that are on this very slight gradient, you can’t move as much water as you used to,” Sneed said.
In the middle of the 20th century, farmers withdrew more than 1 million acre-feet of groundwater annually in the sprawling Westlands Water District. Officials said that’s down to about 200,000 acre-feet a year today, enough to serve about 400,000 homes.
“It’s not what I would call sustainable,” said district resource supervisor Russ Freeman. “But we haven’t severely over-drafted the water table at this point.”
Partly to reduce groundwater use, Westlands has “retired” about 80,000 acres of farmland and farmers let another 40,000 acres lie fallow this year — another sign of shortage even if San Diegans don’t feel it directly. Other valley water districts are storing large volumes of river water underground during high flows in hopes of stabilizing the aquifers during periods of peak use.
But pressure on Central Valley wells has spiked because the U.S. Bureau of Reclamation is only delivering about 40 percent of the river water Westlands was allocated when the Central Valley Project was built. Protections for fish in the Sacramento-San Joaquin River Delta mean farmers likely won’t ever get full deliveries barring multibillion-dollar upgrades to the delta’s plumbing.
That creates problems for Ted Sheely, who grows a cornucopia of crops in the Central Valley using the latest technology to prescribe precise amounts of water needed by different plants.
“We are looking for ways to be more sustainable going forward because we have made the commitment that we are going to stay” despite water shortages, Sheely said. “But really, the bottom line is that if there is not water available, you have to quit growing some of these crops.”
Aug 5, 2012