As many of California’s growers face expected tighter regulations on nitrates in groundwater, Fresno State University unrolled a series of ambitious seminars on water use efficiency, concentrating in the first workshop on fertigation and how to minimize the amount of nitrates entering the groundwater.

The seminar opened with an outline of the serious health threats posed by nitrates in the drinking supply of the San Joaquin Valley. It concluded with some tips on how to target the root zone of plants with needed water – and accompanying nitrogen – and how to avoid going past that root zone, how to protect water sources and how to prevent backflow and spills of fertilizer.

Bill Green, an educational specialist at Fresno State, said that some regions other than Fresno County, which leads the nation in agricultural production, have more stringent regulations related to pollution from nitrates.

But aside from looming regulations, he believes it is in the interest of growers and their advisers to take steps to greater efficiency as has been done in regions that include parts of the Salinas Valley, Ventura County and Nebraska.

Green and other presenters at Fresno State said better efficiencies at delivering nitrogen where it’s needed can save money and contribute to sustainability of farming operations, things that are in the self-interest of growers as well as regulators.

“It’s the right thing to do,” Green said.

The Fresno State event was sponsored by the California Department of Food and Agriculture and its Fertilizer Research and Education Program. It was held at the AgWaterEnergy Center, which is part of the Center for Irrigation Technology.

Upcoming CIT seminars, most of them from 9 a.m. to noon, include workshops on water use efficiency on the farm for small farm operations in Del Rey May 22; Wateright for specialty crops May 23 at Fresno State; air injection June 6 at the Center for Irrigation Technology; fertigation on a production farm in Selma June 13; fertigation for small farm operations July 11 at the CIT; water use efficiency in almonds June 23 at the Fresno State farm and water use efficiency for citrus at the FSU farm Aug. 22.

Green used equipment at the university to show how to protect the water source, how to install an automatic system to shut it down when it is not working properly and how to keep pressurized irrigation system water from flowing back into the fertilizer supply.

He was not bashful about acknowledging his own mistakes as a farmer, including a time when fertilizer spilled from a pumping system’s fertilizer supply resulting in some trees being killed in a peach orchard.

And his demonstration at the university including showing what can happen when nozzles become clogged. His emphasis was on the even distribution of water.