Groundwater nitrate issue dumped in agriculture’s lap

When Jim Sullins, director of Cooperative Extension for Tulare and Kings counties, asked for a show of hands of how many wanted the recent nitrogen workshop to continue after the appointed closing hour, the response was underwhelming.

Fewer than 10 raised their hands. It was obvious the packed meeting room had heard enough from the University of California experts reporting on their recent nitrate-in-groundwater findings.

What drew a crowd of about 200 to the UC Kearney Ag Center in Parlier, Calif., was a recently released UC study of nitrates in drinking water in the central San Joaquin Valley Tulare Lake Basin and the Salinas Valley in Monterey County.

The study has created a statewide media buzz since it says a quarter of a million Californians are hooked to unsafe drinking water wells and agriculture should pay for cleaning it up.

It’s no secret that nitrates in groundwater are a problem. As the study indicates, 250,000 people within the two basins are currently at risk from nitrate contamination in their drinking water. This is out of 2.6 million people who live in the four counties (Fresno, Kings, Tulare and Kern) Tulare Lake Basin and the Salinas Valley, the focal point of the study. Most of these people are on public water systems, not individual wells.

The population of the study area represents only about 7 percent of the state’s population; however, 40 percent of the state’s irrigated cropland is in the study area and over half the state’s dairy herds.

With those statistics, it is not surprising that the nitrate issue was not just deposited on agriculture’s doorstep, it was heaped on agriculture’s back for blame and draconian mitigation recommendations to be paid for by agriculture. Some of the regulatory measures researchers are recommending could reduce farming in the region and the production of food in two of the most productive farming areas in the world.

The study said 96 percent of the nitrates in groundwater are traceable to agriculture. Several in the audience challenged that, and principal investigator Thomas Harter, UC Davis groundwater hydrologist, acknowledged that figure may not be “precise.” However, chief investigator Jay Lund, director of the Center for Watershed Sciences at Davis, reiterated the overwhelming majority of the nitrates are from agriculture.

The study was ordered by the State Water Resources Control Board based on a legislative mandate in Senate Bill SBX2 passed in 2008 that ordered a study on nitrates in groundwater. Harter admitted that the two-year timeline for the study was a “relatively short research project.”