Monterey County and partner water agencies approved a regional monitoring plan and a memorandum of understanding (MOU) intended to improve oversight of the Salinas Valley'''s deep aquifers.

Senior hydrologist Amy Woodrow described the monitoring plan as a coordinated effort to standardize data on extraction/injection, groundwater elevations and water quality across the deep-aquifer extent. The plan draws on the 2024 deep-aquifer study and maps remaining data gaps where additional monitoring is recommended.

"What we're trying to do is make sure that all of the participating entities are doing that data collection on the same frequency so that we have a comparable dataset that covers the entire geographic extent," Woodrow said.

The monitoring plan maps several geographic data gaps (northern, eastern and southern portions) and recommends a shared annual assessment to review the network and address gaps. The presentation noted some observable water-quality variations across the deep aquifer that reflect geologic differences.

Water Resources staff also proposed an interagency MOU to formalize roles and commitments: participating agencies would continue to bear monitoring costs within their jurisdictions while agreeing to cooperate on data sharing, annual reviews and technical coordination. The MOU allows agencies to withdraw if needed.

Supervisors stressed the need to better understand recharge mechanisms and percolation rates into the deep aquifer. Supervisor Church urged an accelerated effort to fill northern data gaps and better characterize connectivity and recharge. Other supervisors supported transparent public reporting and a technical advisory committee composed of agency hydrologists.

The board approved staff recommendations to adopt the monitoring plan and pursue the MOU, directing agencies to continue annual technical coordination and public reporting through normal agency channels.