Tag Archives: groundwater basins

Get to know your groundwater source in Sonoma County

Guy Kovner, THE PRESS DEMOCRAT

For information on the Sonoma County’s Sustainable Groundwater Management program, click here.

The Sustainable Groundwater Management Act, the first law in state history to regulate pumping subsurface water, applies to about 9,000 wells in three groundwater basins in Sonoma County.

Reports by the county Water Agency in 2015 described conditions in the three basins, which essentially cover the county’s flatlands, also its biggest population and farming centers.

Santa Rosa Plain: Covers 78,720 acres from Rohnert Park and Cotati north to Windsor, including Santa Rosa and the east edge of Sebastopol. It has an estimated 6,000 wells.

Groundwater levels in the southern part of the plain declined in the late 1970s through the early 1990s, followed by recovery in the early 2000s. Water quality is generally high, with naturally occurring elements such as iron, manganese, boron and arsenic problematic in some areas and increasing chloride in southern parts of the plain.

Petaluma Valley: Covers 46,000 acres from Penngrove down to San Pablo Bay. It has an estimated 1,000 wells.

Sonoma Valley: Covers 44,700 acres from Kenwood to San Pablo Bay. It has an estimated 2,000 wells.

Groundwater levels in deep aquifers, primarily in southeastern and southwestern Sonoma Valley, have been declining for a decade or more. Water levels in many wells in these areas are dropping several feet a year and have fallen below sea level. Groundwater quality is generally good, except for brackish water affecting wells in southernmost Sonoma Valley and representing a threat if groundwater levels continue to drop.

Read more at: Get to know your groundwater source in Sonoma County | The Press Democrat

Filed under Water

New oversight of groundwater taking shape in Sonoma County – state ending past practice of unregulated pumping

Guy Kovner, THE PRESS DEMOCRAT

Vickie Mulas, a partner in her family’s Sonoma Valley dairy and vineyard operations, is no friend of regulations.“They’re kind of onerous, restrictive and costly,” said Mulas, stating her case bluntly, as farmers often do.

But Mulas, a member of a prominent local ranching family, relishes her role in California’s newest round of rule-making that will — in an unprecedented departure from past practice — put limits on how much water people can pump out of the ground.

She’s a board member on one of more than 100 new agencies statewide — including three in Sonoma County — being formed to implement a landmark California water law that will bring order to groundwater, the aqueous subterranean stores that collectively hold more than 10 times as much water as all the state’s surface reservoirs combined.

In the aftermath of a historic five-year drought that prompted wholesale overdrafting of Central Valley aquifers — triggering dramatic collapses in the landscape — California is replacing a largely hands-off approach to groundwater with a regulatory system that includes metering, monitoring and potentially limiting pumping, along with fees to pay for the regulatory process.

The new order is just starting to come into shape and will take several years to implement, with still-undefined costs, monitoring and limits that in Sonoma County will primarily fall on thousands of rural well owners, including residents and farmers.

The new legal landscape alone is uncharted for California.

County Supervisor David Rabbitt, a member of the two governing agencies that will oversee groundwater in Petaluma Valley and Sonoma Valley, said the state is making a philosophical shift away from the timeworn notion of “sacrosanct” private water rights.

“The aquifer beneath your well is connected to your neighbor’s well,” he said.

For groundwater users in the 44,700-acre basin that supplies Sonoma Valley, the underground creep of salt water and dropping fresh water levels have long been concerns. Now, Mulas and other public and community representatives appointed to the region’s groundwater sustainability agency will have a formal stake in staving off those threats.

Read more at: New oversight of groundwater taking shape in Sonoma County | The Press Democrat

Filed under Agriculture/Food System, Water