Natalie Stork, director of the State Water Resources Control Board’s Office of Sustainable Groundwater Management, spoke at the 2025 California Irrigation Institute conference about the state’s intervention process for groundwater management. She provided updates on six San Joaquin Valley groundwater basins with Groundwater Sustainability Plans deemed inadequate by the Department of Water Resources and outlined the steps needed for these basins to exit the intervention process. Her presentation also reviewed the successes and challenges encountered during the first decade of implementing the Sustainable Groundwater Management Act.
Ten years of SGMA
The first decade of implementing SGMA has been a success. Nearly all groundwater basins subject to the law established the required Groundwater Sustainability Agencies (GSAs), and 98% of these agencies submitted Groundwater Sustainability Plans (GSPs).
“This outcome was unexpected,” said Ms. Stork. “We were aiming for success, and we achieved it. This accomplishment is due to significant collaboration between DWR, the State Water Board, and the GSAs that stepped up to the task. Overall, there’s been substantial compliance and numerous successes.”
Out of 257 submitted plans, the Department of Water Resources (DWR) has approved 170, or 66%, with about 13% still under review. Additionally, DWR has provided roughly $500 million in state funding to support SGMA implementation. Remarkably, 2023 alone saw 4.1 million acre-feet of groundwater recharge.
SGMA implementation has brought significant paradigm changes for managing groundwater for all beneficial uses and users. Many GSAs have recognized they need to focus beyond their own siloed needs and interests, which is reflected in the considerations put into groundwater sustainability plans, outreach, and partnerships.
“We’ve seen GSAs stepping in as new regulatory agencies and recognizing that they’re accountable to more than the water districts or irrigation districts and that now they’re really new regulators in this landscape of groundwater management. We’ve seen GSAs making a lot of progress on addressing dry well responsibility where they allow ground groundwater levels to drop. There are impacts to people who rely on wells, especially shallower wells for drinking water. And there are GSAs out there who are stepping up and recognizing that for impacts to not be both significant and unreasonable, they need to step up and actually replace those wells with deeper wells and ensure people have access to water.”
Additionally, the criteria set by agencies and the planned projects will result in more water supply certainty for the future. “There’s a recognition that engaging in the SGMA process will be essential for providing reliable water supplies in the future, for cities, farmers, everyone being able to plan ahead and know what their water supply looks like.”
SGMA non-compliance
Despite the successes, there are still challenges that groundwater sustainability agencies and regulators are working through.
The green dots on the graphic below show the dry wells reported to DWR since 2013. More than half of them have been reported since 2020 since the groundwater sustainability plans covering the basin were required to be implemented.
The blue dots are wells that have gone dry just in the last year.
“So even after the big water years that we’ve had, there’s still continued challenges,” said Ms. Stork.
Dealing with subsidence is another challenge GSAs are grappling with. The graphic below shows subsidence from 2015 to 2024, with the darkest color being more than 5.5 feet of subsidence.
“This has done hundreds of millions of dollars of damage to infrastructure that’s important for moving water around the state, such as the Central Valley Project and California Aqueduct, as well the levees protecting the town of Corcoran that are on the side of the bowl of subsidence,” said Ms. Stork. “So there are significant impacts and financial consequences for that. And so this is a big challenge that GSAs are continuing to grapple with.”
Basin intervention
The Department of Water Resources is in charge of reviewing the groundwater sustainability plans. If plans are deemed inadequate, they are referred to the State Water Board for possible intervention. In March of 2023, DWR found the plans for the six basins listed on the slide inadequate.
There are five steps to intervention:
- The trigger is when the Department of Water Resources determines a plan is inadequate.
- The State Water Board assesses whether intervention is warranted.
- If it is, the State Water Board can hold a hearing to potentially put the basin on probation.
- The basin has at least one year to address the issues.
- If the issues aren’t fixed, the State Water Board can hold a hearing to potentially adopt an interim plan, which is the Board’s version of a plan. It doesn’t replace the GSP, but is aimed to get the basin back on track for sustainability.
The process at the State Water Board is open and transparent with basin-wide notification requirements to all the State Water Board knows of that may be pumping water in the basin. There are public hearings and several opportunities for people to weigh in through comment periods and stakeholder workshops that are beyond the requirements of the legislation to ensure that locals and others who may be impacted have a chance to weigh in and to have their thoughts considered.
The probation process
At the probation hearing, the State Water Board identifies the deficiencies in the plan, and the GSA has at least one year to address those deficiencies. After that, the Board can decide whether to move towards adopting an interim plan.
For the Board to get the information needed for an interim plan, it requires knowing how much groundwater is pumped. So the law gives the Board the authority to require meters and reporting unless the Board opts some groups out.
“The board recovers its cost via fees,” said Ms. Stork. “The law says the Board has to recover the costs of state intervention and so it’s simply following the directive of the law. But they are not meant to be punitive.”
Update on State Water Board intervention efforts
- Hearings for the Tulare Lake subbasin and the Tule subbasins were held in April and September of last year, and the Board put both of those basins on probation.
- The Kaweah subbasin was scheduled for a hearing on January 7. “However, they turned in a new plan that addressed, on first quick review, all, or nearly all, of the deficiencies identified by State Water Board staff and the Department of Water Resources, so we recommended to our Board, and our Board agreed that we should cancel the hearing, do a full review of the plans that they turned in, and if everything comes up looking good, or any remaining issues can be addressed, then we would move them back to the Department of Water Resources. The statute doesn’t say that the Board has to have a hearing or make a finding in order to do that, but we’ll likely be scheduling something in front of our Board, and hopefully, it’ll be an action item to move them back to DWR, but their plans look really good. They’ve made some significant improvements, and it’s very exciting.”
- The hearing for the Kern County subbasin is scheduled for February 20. “They’ve recently turned in some new plans, and there’s definitely some improvements. We’re very encouraged, but we are continuing to hold that hearing so the Board can consider in an open forum what it thinks is appropriate for the subbasin.”
- The Delta Mendota subbasin has also submitted a new single plan; initially, they had 22 GSAs and seven plans. “They’ve made some good progress, and we’re still looking at options.”
- The Chowchilla subbasin has turned in a new plan. “It looks very good. So we are in the process of working on a staff report, not the 150 to 350-page version, but hopefully a shorter version, and scheduling an action item in front of our Board. We’re working through those last issues, but a lot of really good progress there.”
Exiting state intervention
The key steps to exiting state intervention are for groundwater sustainability agencies to revise their plans and address the deficiencies identified in the Board’s staff reports. The GSA has at least a year to do this. During this time, board staff are holding technical meetings with the basins to work through the issues and refine solutions. The GSA then submits a revised plan which will be reviewed by Board staff. It takes about three months for one plan, and in basins with multiple plans, an additional month for each additional plan.
“Ultimately, the board decides,” said Ms. Stork. “For basins on probation or even basins that aren’t, the statute is really silent until you get up to where we’ve adopted an interim plan. These decisions are going through the Board, so that’s where we’re really focused.”
If efforts to address deficiencies still come up short, then the Board will adopt an interim plan. An interim plan would include corrective actions to get the basin back on track for sustainability, likely including pumping restrictions, monitoring to measure how the actions are working, a schedule, and enforcement to ensure the plan is followed.
There needs to be contingency plans for when there’s a lack of new supplies. “Sometimes hundreds of projects and management actions proposed to get a basin back on track,” Ms. Stork said. “But we don’t know exactly what the future holds in terms of the hydrology, and so we’re looking for contingency or backup plans. What that looks like is likely demand management, especially for where overdraft is occurring, and potentially in places where it’s not occurring.”
“GSAs are relatively new regulatory agencies, and we’re looking for them to act like that,” Ms. Stork continued. “That means do what needs to be done to manage groundwater sustainably and to use their authorities appropriately to work with people when they’re not following the plan. That can be challenging, especially if you haven’t had to do it before, but that’s a key part of sustainable groundwater management.”
Ms. Stork said they would continue working with basins, no matter where they are, because the goal is sustainable groundwater management at the local level. “The biggest challenge the basins are facing is stopping overdraft the sooner, the better, at least by 2040. But where basins are facing a lot of subsidence issues, it may be a lot cheaper to stop subsidence now rather than mitigating all the impacts.”
“Overdrafted basins really need demand management with enforcement and policy decisions need to be supported by best available technical information. It’s hard to fully divorce the policy from the technical; really, those come together, and you need the best available information incorporated for local agencies to make good policy decisions.”
“There are no winners here now. The winners are future Californians if SGMA is done right,” said Ms. Stork. “The real benefit is supply certainty for all different sectors in times of drought. Wells not going dry and safe and reliable drinking water, which, of course, is a big policy mission of the State Water Board.”
