California Groundwater Contamination Widespread While State Water Agency Asleep at the Helm

NRDC uncovers significant pollution after water agency charged with monitoring admits data has not been updated for almost a decade

Bill to address problem passes committee and goes to full Assembly for consideration

SACRAMENTO (April 26, 2001) - Widespread contamination threatens California's groundwater, a source of drinking water for half the state's population and an important supply for agriculture and other uses. But according to a new report, the full extent of damage to the groundwater supply is unknown because the state government fails to comprehensively monitor and assess this vital natural resource.

Evidence of widespread groundwater contamination was documented today in the Natural Resources Defense Council (NRDC) report: "California's Contaminated Groundwater: Is the State Minding the Store?" The report analyzed data from assorted state and federal agencies with overlapping jurisdictions but which collectively fail to monitor and assess groundwater quality in a comprehensive and systematic manner.

The agency most responsible for monitoring the state's groundwater supplies -- the California State Water Resources Control Board -- reported last year that as much as 40 percent of the state's groundwater supply was impaired by pollution or threatened with impairment. After reviewing an advance copy of the NRDC report, however, the agency retracted that assessment and stated that its own report -- the "California 305(b) Report on Water Quality" -- was neither current nor reliable. In fact, the agency admitted that it had not updated the data in the report since 1992, despite a biannual requirement to do so.

In an attempt to assess the state's groundwater using information from other sources, NRDC gathered data from the U.S. Geological Survey, California Department of Health Services, the U.S. Environmental Protection Agency (EPA), the California Department of Toxic Substances Control and other agencies. NRDC found that large numbers of samples from drinking water wells regularly exceed drinking water standards and that a range of groundwater contaminants have been detected at levels that exceed federal or state health standards. The contaminants detected include methyl tertiary-butyl ether (MTBE), chromium, arsenic, pesticides, nitrates and salinity. The data confirm that virtually no region or area is immune from contamination.

"Groundwater is a natural resource of unparalleled importance to California, but the state's approach to monitoring and protecting it is a jumble of disconnected and often ineffective approaches that leave us dangerously unprepared for the future," said NRDC Senior Attorney David Beckman, who co-wrote NRDC's report and directed its groundwater investigation. "The unsettling reality is that California has a widespread groundwater contamination problem, but no one truly knows exactly how bad the situation is -- or how bad it may become."

Contamination a statewide problem

Using the best data available, NRDC's report presents a snapshot of some of the contamination problems in California's groundwater supply, some of which are familiar pollution problems. Groundwater with salinity concentrations exceeding state and federal standards is common in Los Angeles, Ventura, Orange, Riverside, Kern, Imperial, San Bernardino, Fresno, Santa Barbara, San Luis Obispo and Kings counties. MTBE, a gasoline additive, has been found across the state, shutting down water supplies in Santa Monica, South Lake Tahoe, Santa Clara Valley and the Sacramento area. Nitrates from agricultural application of fertilizers also have been detected and are a primary pollutant in water supply wells in the San Gabriel, San Joaquin, Salinas, Chino and San Fernando Valley basins. Pesticides are another contaminant widely found in groundwater, the worst cases found included the San Joaquin Valley, Monterey, Imperial and Ventura counties.

Also of concern are arsenic and chromium 6 (hexavalent chromium), two naturally occurring metals that have been found in heavy concentrations in groundwater supplies in various parts of the state. Many counties have arsenic concentrations at or above a range of 5-10 parts per billion, a level in drinking water which roughly translates to a one in 1,000 cancer risk, and chromium has been found in high concentrations in the San Fernando and San Gabriel valleys.

A patchwork picture and a lack of agency coordination

While NRDC's investigation revealed widespread contamination in groundwater, it also revealed that there is no single agency collecting data on groundwater quality for a broad array of contaminants, and there is no comprehensive and systematic monitoring program in the state. Instead, seven state and federal agencies have limited jurisdiction over some aspect of groundwater quality: the U.S. Geological Survey, the U.S. EPA, the California Department of Health Services, the California Department of Pesticide Regulation, the California Department of Toxic Substances Control, the California State Water Resources Control Board, and the California Department of Water Resources. Among those agencies, data that is gathered may be incomplete, outdated or focused on testing only for a few specific toxics. Sometimes, only certain wells are evaluated rather than whole watersheds, and there is limited effort made to identify potential sources of contaminants. Finally, there is little coordination or communication between the agencies to make any assessment of the condition of groundwater supplies as a whole.

"There is no doubt that California has to fix its hodgepodge approach to groundwater monitoring. What we need is a statewide, comprehensive approach that is cost-effective and equal in scope to the importance of groundwater to California," said Assemblymember Carol Liu (D-La Canada Flintridge), who is sponsoring legislation (AB 599) to address the problem.

Wells are shut down when clean up is costly and difficult

In general, rules require that groundwater supplies with contaminants testing above state or federal health standards receive treatment prior to delivery to consumers. While some types of contamination can be remedied before they reach the tap, the process can be expensive and technically challenging. A common treatment method is to blend the contaminated water with cleaner water. In cases of acute constituents, such as E. coli or fecal coliform, a water supply may be shut down until treatment is completed. However, persistent contamination problems in a groundwater supply have led many communities to conclude that it is cheaper to simply shut wells down and resort to importing water. According to the California Department of Health Service (DHS), which collects data on the state of drinking water wells serving a minimum of 25 people, more than 4,000 wells have been take out of service since 1984, many if not all because of contamination. And DHS does not monitor private drinking wells -- almost one million in total.

Groundwater contamination poses a serious long-term threat for a state with limited water supplies and a growing thirst as the state's population increases. Between 25 and 40 percent of the state's water comes from beneath the ground -- as much as two-thirds in drought years. Californians tap 14.5 billion gallons of groundwater every day. Agriculture also depends heavily on groundwater. There are more than 71,000 irrigation wells in the state, and in the lower Sacramento River Valley alone, almost 750,000 acres of prime agricultural land are irrigated in part by groundwater.

NRDC recommends that to address the scope, quality and accessibility of groundwater quality concerns, the California Legislature must designate a single agency assigned to collect data from the various agencies and survey all groundwater basins in the state. State agencies also must develop a better understanding of existing contaminants, determine the sources of contamination and make that information available to the public on an on-going and consistent basis. Finally, the state needs to fund monitoring programs adequately and ensure proper enforcement of those programs.

About the legislation

AB 599, the Groundwater Monitoring Act of 2001, would accomplish these important goals. The bill, sponsored by NRDC and introduced by Assemblymember Carol Liu (D-La Canada Flintridge) passed a critical milestone yesterday when the Assembly Environment and Toxics Materials Committee approved it and sent it to the full Assembly for consideration.