California’s sweeping new groundwater regulations

Will the law finally mean better aquifer management for the drought-stricken state?

  • Declining water storage in California, represented by colors progressing from green (most stored water) to orange to red (least stored water), as seen by NASA’s Gravity Recovery and Climate Experiment satellites.

    NASA/JPL-Caltech/University of California, Irvine

With dust blowing from the Central Valley’s fallow fields and fires ravaging the Sierra Nevada, California Gov. Jerry Brown signed a package of bills in September that effectively end unrestricted groundwater pumping in the state. “This is a big deal,” said Brown at the signing ceremony. “It has been known for decades that underground water has to be managed in some way.” Now, there’s a statewide framework for aquifer management.

Despite its heavy reliance on aquifers, California is the last Western state to enact groundwater monitoring. In years of average precipitation, groundwater makes up about 40 percent of all water used; roughly 21 million Californians depend on it for at least part of their drinking water.

 But with most of California suffering extreme or exceptional drought, the strain on aquifers has been tremendous this year. In the southern Central Valley, a surge in well drilling helped offset water normally delivered through reservoirs, aqueducts and canals. By some estimates, groundwater has accounted for as much as 65 percent of the water supply this year, and aquifers have been badly depleted.

The new regulations offer little in the way of immediate relief. Nor do they give the state the power to ban pumping outright. But many believe they’re a critical first step toward managing aquifers more sustainably, as California moves deeper into an era defined by water shortages and conflicts. The question is whether the new rules will help remedy a century or more of overuse and extensive damage, all of it carried it out with virtually no oversight.


The rules, which go into effect at the beginning of 2015, require the state’s Department of Water Resources to identify “high” and “medium” priority basins, which then must establish local groundwater sustainability agencies and develop monitoring plans. (Though the basins have not yet been identified, it’s likely that many will be located in the southern reaches of the Central Valley, where overdraft has been most severe.) These plans, which require each basin to achieve “groundwater sustainability” by 2040, must be completed within five or seven years, depending on the priority. If deadlines aren’t met, the state water board can intervene and establish an interim plan.   

In addition to its new monitoring requirements, the law also requires local agencies to look for ways to apply “conjunctive” management of ground and surface water — treating rivers, streams and lakes, along with aquifers, as a connected hydrological system. It’s the first time the connection between ground and surface water has been explicitly acknowledged under California law. “If there has been an upside to the drought,” says Jay Famiglietti, a hydrologist at the University of California, Irvine, “it’s that it has brought sustained focus on groundwater to get this legislation passed.”

The package of bills, authored by state Sen. Fran Pavley, D-Agoura Hills, and Assemblyman Roger Dickinson, D-Sacramento, comes after emergency water-saving restrictions in July banned wasteful activities, such as hosing down sidewalks and washing cars without water-saving nozzles. Brown has also used the drought to build support for a $7.1 billion water bond on the November ballot. (At press time, the vote had yet to take place.) This includes funding for drought relief, dam building, groundwater cleanup and devising regional water-management plans. 


California’s population has more than doubled over the past 50 years, to 38 million, and competition between farms, industry and municipalities for water has grown increasingly fraught. In most parts of the state, landowners were allowed to pump without limits. Where regulation was happening, it was often piecemeal and the result of lawsuits between water-rights holders, or it was implemented through local ordinances and agreements between counties, cities, water agencies and other stakeholders.

California’s powerful agricultural lobby, however, strongly objects to state oversight. Paul Wenger, president of the California Farm Bureau Federation, says that the new regulations will inevitably cause confusion and bring lawsuits from farmers, who doubt that the state has enough storage to compensate for restricted pumping. Property values could suffer as a result, critics say. “With the stroke of his pen, the governor changed over 100 years of water laws — without the people’s input. This is not the democracy Californians deserve,” says Jim Nielsen, a rancher and Republican state assemblyman who represents a large agricultural district.

But it’s hard to argue that sweeping change isn’t needed. Overall, the valley’s aquifers have lost 60 million acre-feet since 1960, according to a 2009 U.S. Geological Survey report. In vast swaths of the Central Valley, the water table has fallen by as much as 60 feet in the last year alone.  A new study from UC Davis estimates that water shortages have led to the fallowing of over 400,000 acres in the Central Valley this year, resulting in the loss of more than 17,000 seasonal farming jobs. Several small towns in Tulare County, near Fresno, have run out of water entirely.

Given such serious challenges, some say the new law’s deadlines are too lax, noting that the state could face disaster if 2015 is as dry as 2014.  Others cite vagueness in the language; “groundwater sustainability,” for example, is not defined precisely.

That allows local authorities to decide, says Famiglietti, and is an important reason the law passed the state Legislature without much resistance. One definition, he says, could impose a limit beyond which pumping is not allowed. Another could accept that long-term depletion will occur, but within specified limits.  “The opportunity for local (control) assuages the fear that the state is going to come in and say you can’t pump this much groundwater,” he says. 

Compounding the California law’s slippery definitions of sustainability and its deference to local agencies, says University of Arizona law professor and author Robert Glennon, is an inadequate understanding of groundwater resources. One major obstacle is the lack of public access to the detailed technical reports compiled by well drillers.

California is the only Western state where well logs are not publicly available, the result of a 1950s tweak to the state water code that has largely benefitted private drillers who don’t want data shared with competitors. Though there are exceptions for government agencies, most researchers trying to create a comprehensive picture of California’s groundwater basins have been denied a critical source of information. “For hydrologists who want to know what’s going on underground,” says Glennon, “the data is very important — and it’s just not available.”

While the new law is an important step, says Glennon, it may not prove effective in restoring California’s aquifers. That’s because the water districts and rights holders that benefitted from unchecked pumping will, in all likelihood, retain a role in managing local groundwater supplies through the new groundwater sustainability agencies. He points to similar laws in Texas and Nebraska that have done little to curb overdraft.

A more promising model, Glennon says, can be found in his home state: “There aren’t many instances where Arizona is more progressive than California, but this is one of them.” Arizona’s 1980 Groundwater Act allowed the state to prohibit new wells in severely overdrafted basins. And while Arizona’s law didn’t prevent pumping, it limited groundwater-rights holders to specific quantities based on historical use, says Glennon. It also required rights holders to reduce their water use in accordance with statewide targets.

 “I can’t say Arizona’s plan has been flawless,” says Glennon. “But a blueprint for a successful plan in California would include these basic elements.”

Correction: An earlier version of this story cited a 2013 USGS report, when in fact it was a 2013 USGS press release that was referencing a 2009 report. HCN regrets the error.