The other water quality regulatory shoe is dropping on California agriculture, and it could be very costly, casting a net over just about everyone who farms in the state.

Since 2003, the State Water Resources Control Board and nine regional water quality boards have focused on protecting the surface waters of the state’s 9,500 miles of rivers/streams and 513,000 acres of lakes/reservoirs from pollutants.

Those involved in that seemingly Herculean task contend that through monitoring to identify pollutants and plans formulated to preclude pollution, the surface water quality mandate is being successfully met.

More recently, the state and regional boards have switched focus to protecting groundwater. That is becoming a much larger can of worms because it impacts everyone since there are countless wells, both domestic and agricultural.

“What we have proven is that overall, ag pollution of surface waters is fairly minimal,” says David Orth, coordinator of the Kings River Watershed Coalition, a member of the larger Southern San Joaquin Valley Water Quality Coalition.

That is not to say agriculture is blameless. There have been areas where agricultural pollutants were reaching waterways. However, the widespread monitoring, according to Orth, did not turn up agricultural pollution on the scale many assumed.

(For more, see: Groundwater nitrate issue dumped in agriculture’s lap)

Orth and Parry Klassen, executive director of the East San Joaquin Water Quality Coalition, say the most vulnerable areas have been identified and best management practices have been developed to reduce or eliminate pollutant runoff.

“We contacted every grower in the east valley coalition in these vulnerable areas and worked with them to change their farming practices to preclude pollution,” said Klassen. “We have had excellent cooperation.” Orth agreed growers have been cooperative and that has made the program successful.

Surprisingly, these vulnerable areas represented less than half of the farmland contained in these coalitions. For Orth’s group, it was only about 20 percent of the southern San Joaquin Valley. For Klassen, those vulnerable areas represented only about 40 percent of the coalition’s 1.1 million acre area of Madera, Merced, Stanislaus, Tuolumne and Mariposa counties.

That is the good news part of what is called the California Irrigated Lands Regulatory Program. The bad news is that the second phase of that, mitigating groundwater pollution, will likely stretch far beyond the scope of the surface water regulations.

Not only will the groundwater regs impact just about everyone, but there is likely to be a hefty mitigating price tag. The cost to monitor groundwater will be considerably more expensive than the surface water package. And grower compliance with the regulations will likely be more costly. There are also the so-called clean-up costs, which many are saying can be paid by taxing farmers for fertilizer use.