Below-ground pools: Sacramento County wrestles with governing its groundwater

For the first time in California history, government regulation is being applied to the pools of water hiding underground.

Between 1920 and 2013, Californians drained an estimated 41 trillion gallons of groundwater, or 441 billion gallons annually, from beneath the Central Valley, the largest aquifer in the state. That pace increased dramatically during the five-year drought: Up to 1.96 trillion gallons were pumped per year, when frantic farmers and ranchers tapped the earth to make up for what no longer fell from the sky.

The U.S. Geological Survey considers groundwater supplies similar to savings accounts. If they’re not replenished, the environmental risks are broad, causing dry wells and, eventually, soil collapse, which result in sinkholes and dropping valley floors. Depleted groundwater supplies also starve out ecosystems by reducing stream flows.

Historically, the state has regulated rivers, lakes and reservoirs, but it didn’t regulate groundwater until 2014, when legislators enacted the State Groundwater Management Act.

Now, Sac County and other governments are racing to form groundwater sustainability agencies, or GSAs, by a state-mandated deadline of June 30. If local GSAs aren’t formed by then, the state water board can intervene in the name of keeping aquifers from falling further, and force counties to recover costs for developing monitoring plans, performing studies and requiring data reporting.

There are three main subbasins beneath the county, named the North American, South American and Cosumnes subbasins.

The North American subbasin is bounded by the American River on the south and extends into Sutter and Placer counties, which are expected to put in their own GSA applications for their portions of the subbasin. The Sacramento Groundwater Authority manages the portion inside Sacramento County and already collects $600,000 annually for its work. Future money could be spent to build groundwater recharge facilities, develop a groundwater sustainability plan and more.

On March 1, staff suggested funding Sacramento County’s GSA through Zone 13, a water agency and property tax zone in the southeastern county that brings in $2.2 million a year for flood control, water supply management and conservation. Supervisors were hoping to use the existing Zone 13 revenues for future groundwater sustainability efforts in those unmanaged areas to prevent state intervention. But staff said the money collected wouldn’t be enough, with future studies, outreach and administrative costs to bear.

Supervisors will reconvene on April 11 to decide what unmanaged areas could fall under the county GSA. If the county creates its GSA, it will also be able to charge groundwater extractors and users, a group that encompasses utilities, water districts, cities and, ultimately, taxpayers.

The process has sparked local interests to grapple for control over Sacramento County’s valuable water aquifers.

The South American subbasin, which is fully contained in Sacramento County and extends from Folsom through Elk Grove, has seen three overlapping GSA applications. Those overlaps must be addressed prior to the state’s June 30 deadline, and the Sacramento Central Groundwater Authority has attempted to do so by putting forth an “alternative plan” that would allow it to control the territory, based on the argument that it’s managed the subbasin responsibly for the past decade.

The Sloughhouse Resource Conservation District, which is behind one of the competing GSA applications, sued the groundwater authority over its continued management of the subbasin. The Sloughhouse district’s attorney, Hanspeter Walter, criticized the groundwater authority’s plan last week.

“What it really would do is make an end-run around the Sustainable Groundwater Management Act,” Walter told supervisors. “This would set in stone old management procedures and assumptions and not trigger the new SGMA provisions.”

Advocating for a formal GSA, Walter added that the Department of Fish and Wildlife Resources, conservator Trout Unlimited and a coalition of environmental groups are also concerned.

The board of supervisors saw little opposition from agricultural interests last week, possibly because the local regulations won’t be fully implemented until 2040. In the meantime, farmers are busy ramping up drilling and installing larger, more powerful pumps while they can. A Sacramento Bee study found 2,500 new wells added in the San Joaquin Valley last year alone, five times the average for the prior 30 years.