At the May meeting of the California Water Commission, the Commission was updated on the implementation of the Sustainable Groundwater Management Act or SGMA, including state activities related to the Commission’s May 2022 White Paper on groundwater trading, an update on SGMA implementation, and the semi-annual groundwater conditions update. Tim Godwin, the advisor to DWR Deputy Director Gosselin, gave the update.
Groundwater markets
Item 3.6 of the Water Resiliency Portfolio Directs an interagency team to “create flexibility for GSAs to trade water within basins by enabling and incentivizing transactional approaches, including groundwater markets, with rules that safeguard natural resources, small- and medium-sized farms, and water supply and quality for disadvantaged communities.”
In March 2021, the California Water Commission was asked to gather expert and public input and make recommendations on what role the state should take to support groundwater trading. The Commission completed the white paper in May of 2022, which evaluated existing practices and provided findings and recommendations for state agencies.
The Department of Water Resources is now convening an interagency workgroup that includes the State Water Resources Control Board, the Department of Fish and Wildlife, and the Department of Foos and Ag. The workgroup is developing a work plan to implement the recommendations in the Commission’s white paper. Their effort will include lessons learned from markets already established by Rosedale Rio-Braco, Fox Canyon, and Madera County.
“They all have unique circumstances that challenge them on several fronts,” said Mr. Godwin. “Those are providing solid feedback from those early adopters to help us understand the pitfalls we can avoid so that we don’t fall into the same traps.”
The slide shows the goals outlined in the Commission’s white paper. The workgroup is currently focusing on Group 1 actions, which are within existing authorities; Group 2 actions will be explored as the group moves forward.
“We are looking at the specific authorities within our state agencies to really step into this space and consider whether or not specific rules are required or if guidance is enough,” said Mr. Godwin. “That’s the next phase after we get through developing an initial guidance document.”
SGMA Update
Ten years into SGMA, and implementation is moving quite rapidly:
71 basins have submitted groundwater sustainability plans that have been approved. Mr. Godwin noted that approving the plan is just the first step; every one of these approved basins came with recommended corrective actions and things they needed to work on.
Thirteen basins have plans deemed incomplete, meaning DWR has found deficiencies that preclude approval based on the regulations. Those basins have six months to address the deficiencies and resubmit to the Department. Mr. Godwin noted that several basins have already resubmitted their plans.
Six basins from the 2020 plans submitted by basins determined to be critically overdrafted have been deemed inadequate and referred to the State Water Board for consideration of the state intervention process and probationary status. The Tulare Lake Basin was recently put on probation; the other basins are slated to be likewise considered. Those basins are working hard to address their plans and resubmit alternative plans to the board.
“The State Board says they intend this to be a temporary process and intend to get them back into local control under the department’s purview in terms of review and tracking of their implementation,” said Mr. Godwin.
SGMA has created a ‘firehose’ of data through the annual reports submitted every April 1st. It’s a tremendous body of information that hasn’t been available before. There will also be periodic evaluations, generally on a five-year basis.
“These are the opportunities for the Department to play both hats,” said Mr. Godwin. “One, we have a regulatory role in evaluating whether or not those groundwater sustainability plans are achieving their objectives. And two, we’re providing technical planning and financial assistance. All of these pieces come together for what I feel is a robust support mechanism for the GSAs to move forward and achieve the very tall task of sustainability in some of these basins.”
The Department is transitioning to the role of ‘basin stewardship’ in our capacity to work with GSAs and track their implementation. ‘We intend to be right there with them. As much as the GSAs want us to be there, we’ll be there. We will have staff dedicated to each of these basins, both from our region offices as well as our headquarters. And we will be looking at how implementation is going, identifying those pitfalls and what needs they may have, so we can adapt our assistance role to provide those as appropriate statewide.”
One of the Department’s accomplishments is the collection of data from the AEM surveys, which is now complete for all of the high and medium-priority basins. The data is available online for the GSAs to use. It is valuable to understand where recharge can occur and to help local agencies plan their projects to get the water into the ground and leverage their basins as green infrastructure to increase storage.
The Department is also working on three guidance documents:
- Interconnected surface water depletions caused by groundwater pumping: This is one of the six sustainability indicators in SGMA and is the most complex. So, the Department is currently developing a series of guidance documents; it’s a literature review with context for how it applies in California. One paper has already been released; the next two are upcoming. Those will be followed up with a specific guidance document that defines how to establish sustainable management criteria. “So you might be able to quantify your depletions,” said Mr. Godwin. “But the hard question is, what is the significant and unreasonable impact of that depletion of interconnected surface water?”
- Subsidence: The Department is working on a guidance document to support GSAs in avoiding land subsidence; it will be coming out this fall. “Punch line there is reduce your pumping; that’s the bottom line for subsidence.”
- Water market guidance: This will come out of the work plan discussed at the beginning and will address how local agencies may be able to establish trading platforms to support their management of groundwater resources.
Annual groundwater conditions report
Lastly, Mr Godwin covered the annual groundwater conditions report for 2023. The graph below shows the relationship between precipitation and groundwater conditions. The solid line is the mean precipitation across the state; the trend is clearly decreasing. The dashed red line shows groundwater storage.
“Every time groundwater storage goes down, that’s an opportunity for more storage of our surface waters,” said Mr. Godwin. “There’s an empty basin out there; we can fill it. This is cheap storage. It’s right in front of us. We just need to figure out how to use it.”
The slide shows the numbers for Water Year 2023. What’s unique about that period is the shift from significant drought to a flood in just a few months. “We have all this data coming in about what is going on with the groundwater sustainability agencies, what actions they took and what observations they made, and how the groundwater conditions have changed. This is a tremendous new opportunity to understand how these systems function, the timelines, the volumes, and where our opportunities are to maximize and become more resilient on a localized and regional scale.”
Mr. Godwin pointed out that groundwater pumping was cut in half, and groundwater storage rose by 8.7 MAF; there was less subsidence and fewer dry wells. However, he noted that there was 14 MAF of loss just in 2021 and 2022. “We refilled some of that space, but we have a lot more to fill, just looking at those three years. So it’s going to take more than just one wet year to overcome our storage reductions.”
The increase in managed recharge was impressive: 4.1 million acre-feet in 2023, and even in dry years, some recharge occurred.
The map on the slide shows where significant recharge was occurring. The most recharge occurred in the Tulare Lake Basin, where floodwaters were moved into recharge basins, farm fields, and established water banks.
The slide lists the state’s actions to support groundwater recharge. The executive orders were very effective and allowed the Department to support local agencies.
The law allows for diverting floodwaters when there is a declared emergency and an imminent threat to life and property downstream; however, no diversions occurred. Mr. Godwin attributed this to concerns over public safety and the risks in making that determination. “We will be working with local and regional flood managers to help refine that and understand where those limits are and the opportunities to divert off waters that would otherwise go on through the system. Those waters may be very important to the aquatic ecosystems and the Delta – I’m not saying we will capture all those. But let’s start talking about where those opportunities may exist and how we can capture some of those.”
The State Water Board established a streamlined permit process to support local agencies in capturing high flows with their temporary recharge water rights permit; however, Mr. Godwin noted that only a small amount of what was permitted could be diverted. There were a variety of reasons; some rivers may not have reached high enough flows for water to be captured and diverted; agencies may not have had enough places to put that water, or there may have been dairies or other water quality reasons for not being able to divert.
“So we are actively working with the State Water Project team and the California Water Plan team within DWR to figure out how to expand opportunities,” Mr. Godwin said. “We’re also working with the State Board, CDFW, and CDFA to figure out how we can optimize and identify those opportunities to get to what we need to better capture some of these higher flows.”
The Department has given out $121 million to 69 Groundwater agencies to implement groundwater recharge projects. It’s added roughly a capacity of 850,000 acre-feet.
There are other opportunities, such as LandFlex, which pays farmers to take land out of production; when the rains came, some farmers were able to put it on their fallowed fields, so they are getting multiple benefits. However, with the current budget deficit, that program will not be able to continue, so they will be talking with NRCS and others about how they can build on existing programs to help minimize the impact of fallowing and maximize the recharge and building of resiliency so that the agricultural and the communities that rely upon those practices can continue.”
The slide shows groundwater conditions over the past year, five years, and twenty years. “The map on the left is what happened last year; it indicates where groundwater levels increased. But if you put that in the context of the last five years or the last 20 years, again, you can still see a general decline in groundwater levels. These groundwater basins can store a lot of water. We need to find a way to get the water when we have it into the system so we won’t lose it. And it is now being managed by these groundwater sustainability agencies. It’s a much more resilient system.”
Lastly, Mr. Godwin turned to subsidence. One of the intents of SGMA was to avoid or minimize subsidence. Coming out of the 2016 drought, there were areas of the state with subsidence rates in excess of a foot per year. “That’s a lot … think about that coming in under your property – it may break your foundation, it may break your water conveyance system. High-speed rail is out there; they are seeing these impacts, and they have to adapt to address them. The GSAs are having to adapt to address them. And they’re taking it very seriously.”
Mr. Godwin pointed out the patches of blue in 2017 and 2023, both wet years. “That’s not subsidence – that’s rebound. That’s the earth coming back up. This is the elastic response with subsidence. However, I want to point out we went from dropping at a foot a year to coming up .1 feet in the year; the next year, a dry year, we saw subsidence returned to those areas. So, while it may come up a little bit, it’s more like a tennis ball bouncing down the stairs; bounce, it comes up, and then it goes down; bounce up, come down.”
In closing, Mr. Godwin noted a significant reduction in subsidence rates in the Central Valley. “That’s because we’re using the available surface water, we’re getting more efficient, and the local GSAs are striving to address these issues and minimize those impacts. And we hope that as we move into the next dry season, we’ll continue to build upon our recharge projects to build the resiliency and utilize these groundwater systems more.”
PUBLIC COMMENT
The Commission then took public comment.
Ben King said that if there are going to be markets, there needs to be standards for water quality, as some supplies may have a lot of contaminants. Every market needs standards; otherwise, people will game the market.
Tien Tran, policy advocate at the Community Water Center, called on the Commission to highlight the human right to water in their consideration; groundwater trading should provide real allocations for drinking water and safeguards for disadvantaged communities.
Sarah Heard from the Nature Conservancy encouraged the Department to look at the specific recommendations around engaging stakeholders, especially vulnerable users, and assessing GSA’s needs in developing best management practices. She also encourages an external technical advisory group as the work is complex, and there are a lot of benefits to leveraging outside and diverse expertise.
COMMISSION DISCUSSION
Commissioner Curtin noted that the most appropriate places for groundwater recharge can sometimes be out of local control. Is the Department going to get to a point where they can do some mapping and figure out the ideal situation for groundwater recharge? Under the SGMA program, there might be the capability of a bond for the infrastructure necessary to deal with groundwater in conjunction with surface storage. There needs to be an understanding of how big the capacity is and how easy it can be done.
“The watershed studies the Department is developing are looking at a larger scale that the basins are part of, and looking at where we can capture those high flows and move them into the system through existing infrastructure,” said Mr. Godwin. “We’re already evaluating the existing infrastructure in some of these watersheds throughout the San Joaquin Valley. … There is the San Joaquin Valley Collaborative; they are evaluating more robust integration and coordination across the valley about how they can capture, store, and move around water for recharge purposes and conjunctive use purposes as well. There’s also the San Joaquin Valley Blueprint. … the organizations, the local agencies, and the State Water Project contractors are involved and listening and trying to find ways and opportunities to develop new partnerships with local agencies.”
Commissioner Gallagher asked where the data for groundwater levels came from.
“It’s the physical measurements that the groundwater sustainability agencies are performing as part of their monitoring responsibilities. The cornerstone of SGMA is that it is about the physical groundwater conditions – not what a model tells you, not what you’re hoping to be, but what’s measured. So these are direct reports from the groundwater sustainability agencies that they are reporting to us on a regular basis. And access to the data is absolutely paramount for us to be fully transparent. This data is uploaded into the portal and is accessible to anybody who wants to pull it down and use it.”
Commissioner Gallagher asked if they can overlap water quality monitoring data with the best areas for groundwater recharge.
“Absolutely,” said Mr. Godwin. “One of the critical pieces of feedback we had of Water Year 23 was so much recharge occurred, and there were immediate concerns over the water quality impact implications for the groundwater users as these waters percolate through salt-loaded and nitrate-loaded areas. So we’re actively working with the GAMA program at the State Board and Sustainable Conservation to go out and sample some of these wells and start to understand what that impact was. So, we’re collecting some additional data, which will feed into our basin characterization work and be reported out that way.”
Commissioner Gallagher noted that not every GSA is likely to have the best places for groundwater recharge, so conveyance would have to be a part of something like that. Have you considered how that would look if recharge areas were unavailable for every GSA?
“The sad fact is geology matters, and we can’t change the geology, so we have to work within it,” said Mr. Godwin. “We can’t work within it if we don’t know what it is. So we’ve been really focused on characterizing the geophysics. And we’re pushing that forward with additional, more detailed studies in areas where we know coarse-grained sediments and knowing where those pathways are. Those are considered natural pipelines; we can tap into them, take floodwaters off of the system, and put them into these locations where they can percolate at a very high rate. That’s pretty easy. Moving that water from where it is to where it needs to be, though, may not be so easy.”
