Water pipes connected to a well underground
photo credit: UDSA/flickr

Some 40,000 water wells dot the Sonoma County landscape and they’ve got some new rules.

Despite concerns over data gaps and allowable pumping, Sonoma County’s board of supervisors approved a new slate of regulations for water wells by a 3-2 vote Tuesday, April 4th.

Supervisor Susan Gorin, one of two no-voters, said the rules don’t go far enough to protect dwindling groundwater in vulnerable areas.

"Last year, we found that in Sonoma Valley, the rate of withdrawal was about 1400 acre feet greater than the sustainable recharge rate," Gorin said. "We have a responsibility to stabilize that withdrawal."

The new rules also establish a low flow well threshold of two acre feet a year.

That's a major concern for Gorin, the other dissenting voter Supervisor Chris Coursey, and a number of organizations ranging from the National Marine Fisheries Service to the Sonoma Ecology Center.

Permit Sonoma’s Robert Pennington explained the reasoning for the two acre foot threshold instead of a half acre foot - the average use for most household wells.

"One of our objectives is to keep this ordinance as simple as possible," Pennington said. "We feel that a threshold of 0.5 acre feet per year, that would be very restrictive, in terms of what folks can do with their land and add considerable costs to low water use parcels."

Another big concern: the protection of water as a “public trust” deserving of special protection, as well as a lack of complete data on the county’s groundwater.

Jessie Maxfield is with the California Department of Fish and Wildlife, and helped work on drafting the new regulations:

"Some incredibly important conversations were started regarding the potential impacts to public trust resources from well drilling, and the ways in which those impacts might be avoided or mitigated," Maxfield said. "I use the word started because we are not finished. I don't think there was a single member of the technical work group who felt that we had enough data and information to adequately inform the recommendations."

The new rules will include water conservation and reporting requirements for some wells, and they will come before county officials for a second reading and final approval April 18th.

A temporary moratorium on new well permits was also continued until May, when the new well regulations are scheduled to go into effect.