Nitrate Contamination
in California’s Drinking Water Supply
By Linda Sheehan California Coastkeeper Alliance

» Nearly half of Californians rely partially or entirely on groundwater for their drinking water supply. While most of the state is able to provide safe drinking water, many communities (primarily in the poorest areas) must drink contaminated groundwater. For example, in Tulare County — in the heart of California’s vast Central Valley growing region — 20 percent of small public water systems are unable to regularly supply safe drinking water due to nitrate contamination. And more than 40 percent of the 181 private wells tested by the State Water Board in 2006 violated nitrate standards. The number of public water systems violating nitrate standards increases significantly each year.

Nitrate contamination in drinking water primarily results from unregulated or under-regulated activities such as fertilizer applications, discharges from animal factories and food processors, and leaking septic systems. At the higher concentrations seen in some drinking water supplies, nitrate can cause stillbirths, infant deaths and cancer in adults.

Unfortunately, nitrate contamination of drinking water supplies disproportionately impacts our smallest and poorest communities, farm labor camps and schools. One example is Tooleville, a community of approximately 350 people located near the city of Exeter in Tulare County. Residents are primarily farm workers with a median household annual income of $16,000. A nonprofit mutual water association provides water to the community from two wells, both of which produce water with nitrate over the Maximum Contaminant Level (MCL). Tooleville residents have tried drilling wells deeper and in the surrounding areas, but cannot locate an aquifer with water under the MCL for nitrate. The Friant-Kern Canal, which carries relatively clean surface water, flows literally a few feet from the system’s well. But the community does not have access to that water, nor could it likely afford the treatment and infrastructure necessary to use it without other users to share the costs.

In partnership with Baykeeper, California Coastkeeper Alliance and other allies — including the Community Water Center, Clean Water Action/Fund and the Environmental Justice Coalition for Water — are taking action to address this problem and ensure all Californians enjoy clean water. First, we are taking on the Central Valley Regional Water Quality Control Board’s failure to protect these communities through not enforcing their own mandate to protect groundwater from nitrate pollution. Under California law, regional water boards must regulate all discharges — including from irrigated agriculture — to protect all waters of the state, as well as groundwater. But lax regulation, oversight and enforcement in the Central Valley and elsewhere has shifted the burden of controlling nitrate discharges from those who created them — such as corporate farms, animal factories and food processors — to communities least able to should that burden. These groups have filed petitions against the Regional Water Board for failure to adequately regulate irrigated agriculture and dairy facilities in the Central Valley.

Additionally, the Community Water Center works directly with many of these communities in outreach, education, organizing and technical assistance to help communities develop long-term solutions to drinking water problems, access bond funding and other sources of funding and expertise. Currently the center is working with Clean Water Action, the Environmental Justice Coalition for Water and California Rural Legal Assistance Foundation to develop comprehensive programs in the Central Valley and Central Coast to address nitrate pollution and dilapidated infrastructure.

While our poorest communities have borne the brunt of our misguided water policy until now, California’s laws give us all a critical opportunity to make the state a national leader in protecting groundwater quality. It is our goal to make that happen so that clean drinking water, a basic human right, is a right available to all. w