The Monterey County Board of Supervisors reviewed responses to a Civil Grand Jury report that outlined several recommendations for addressing seawater intrusion in the Salinas Valley Basin.
The board, as well as the Monterey County Water Resources Agency, approved Tuesday a draft joint response to the grand jury report called “Seawater Intrusion — A Shared Problem in Monterey County.”
California’s civil grand jury system provides independent investigations into issues in counties and is composed of residents who select which areas or problems they want to explore. The jury creates its report and then requires leaders such as boards of supervisors, city councils or city or county departments to respond.
The issue of seawater intrusion into groundwater supplies in Monterey County has come up as a topic among previous civil grand juries since the 1990s. Portions of the Salinas Valley Groundwater Basin, which are used as municipal and agricultural water sources, have continuously seen seawater intrusion due to overdraft.
Overdraft occurs when groundwater pumping exceeds natural recharging from sources like rainfall and river flows. Reduced pressure from freshwater can cause seawater to move inland, thus flowing into the groundwater aquifers.
The basin is divided into subbasins, or aquifers, that serve different areas.
“These conditions have resulted in the loss or impairment of wells and continue to threaten long-term groundwater reliability,” the report reads.
One subbasin in Monterey County, the 180/400-foot aquifer, has been identified by the state as critically overdrafted and is required by the state to achieve sustainability goals by 2040. If there is not substantial progress made in reaching sustainability, the State Water Resources Control Board could intervene, potentially reducing local control over mitigating seawater intrusion.
Grand Jury’s recommendations
The Civil Grand Jury recommended that while studies and mitigation plans have moved forward, further progress could be made by “defined project selection, coordinated governance, and sustainable long-term funding.”
The report recommends taking a collective, multi-agency approach to speed up efforts to mitigate seawater intrusion in the Salinas Valley Basin. Three agencies — the Board of Supervisors, the Salinas Valley Basin Groundwater Sustainability Agency, and the Monterey County Water Resources Agency — are among the agencies responsible for groundwater management in the county that the report named.
For the board, the Civil Grand Jury suggested that it conduct a public study session to evaluate long-term funding options to further support groundwater sustainability projects led by the Salinas Valley Basin Groundwater Sustainability Agency. The report asked the board to direct staff to come back in June 2027 with a list of possible funding mechanisms, which the board agreed to.
“Regional collaboration is vital if Monterey County is going to successfully move from planning to implementation on a meaningful scale.”
Board of Supervisors’ draft response
The board also proposed establishing a regional water forum bringing together the numerous involved agencies as a way to work together toward an integrated strategy.
“Regional collaboration is vital if Monterey County is going to successfully move from planning to implementation on a meaningful scale,” reads the board’s draft response.
The Monterey County Water Resources Agency also responded to the report but had some disagreements with the findings.
The Civil Grand Jury’s recommendation to the agency’s board of directors pertains to the Castroville Seawater Intrusion Project, which provides an alternative water supply for agricultural irrigation in a designated service area in the northern Salinas Valley.
Inconsistent implementation
According to the report, similar alternative water supplies have not been implemented in other areas outside the project’s service area that are also experiencing groundwater stress.
“This uneven distribution of alternative supplies limits basin-wide progress toward reducing groundwater pumping,” the report reads.
The grand jury recommended that the agency’s board of directors prepare a feasibility and financing plan identifying solutions to expand alternative water supply infrastructure or develop new projects outside the scope of the Castroville service area by March 2027.
While the agency agreed with the intent of the recommendation, the idea “will not be implemented because it is impractical,” the draft response reads.
The Water Resources Agency pointed out that the Salinas Valley Basin Groundwater Sustainability Agency is charged with developing solutions to achieve groundwater sustainability, and it already has six feasibility studies underway.
The Water Resources Agency argued that starting a separate project could cause confusion among the public, “run the risk of duplicative efforts,” or risk having both agencies submit competing proposals, the draft response read.
“We recognize that there’s a need there, but for the Water Resources Agency to step into that space would be impractical,” said the agency’s General Manager Ara Azhderian at a meeting earlier this month. “It runs a number of great risks.”
The Water Resources Agency and the Board of Supervisors have until mid-August to submit its final responses to the report. The Salinas Valley Basin Groundwater Sustainability Agency is working on its own response to the report’s recommendations.
