Guy Kovner, THE PRESS DEMOCRAT
The shallow wells Sonoma County’s water agency is drilling near 11 waterways have nothing to do with delivering water to 600,000 residents of Sonoma and Marin counties.
Instead, the 21 wells will serve as measuring sticks to determine whether pumping groundwater in the county’s three basins — the Santa Rosa Plain, Petaluma Valley and Sonoma Valley — is curbing the flow in creeks inhabited by federally protected fish and other species.
The $300,000 project is the latest consequence of a state law, enacted during California’s five-year drought, requiring long-term sustainability of underground water supplies that were heavily tapped during the prolonged dry spell.
And that means assessing the connection between surface water and groundwater and possibly, for the first time in state history, setting limits on use of well water by residents, ranchers, businesses and public water systems.
“We can’t see what’s beneath the surface, so these monitoring wells will act like underground telescopes. They can help us see how much and when water is available,” county Supervisor Susan Gorin said in a statement.
Gorin is chairwoman of the Sonoma Valley Groundwater Sustainability Agency, which covers the basin seen as most susceptible to depletion. Local agencies were formed in 2017 in each of the county’s basins to implement mandates of the Sustainable Groundwater Management Act that became law in 2015 amid the state’s historic drought.
Farming interests generally have taken a dim view of the increased monitoring and prospect of pumping limits. During the recent drought, when stream flows were greatly diminished statewide, Central Valley farmers especially drew heavily on groundwater at rates that officials said were unsustainable, risking a whole host of related environmental impacts — on drinking water, soil and wildlife.