The MSGSA has developed, and adopted on June 12, 2025, a Groundwater Allocation Rule that will be used by the MSGSA to administer and govern the allocation of native groundwater available to agricultural lands within the MSGSA’s boundary.  The implementation of the adopted Rule will enable the MSGSA to reduce the consumptive use of native groundwater to meet the objectives of the Merced Subbasin Groundwater Sustainability Plan, as adopted by the MSGSA on July 19, 2022, and approved by the California Department of Water Resources on August 4, 2023.   

Additionally, the MSGSA has developed a Groundwater Accounting Platform that provides landowners with the ability to monitor groundwater use that will become more limited through the adopted Rule governing groundwater allocation.  From now through December 31, 2025, the platform will be limited to helping landowners view and track water use on their lands.  Beginning January 1, 2026, the MSGSA will begin monitoring water use against the groundwater pumping allocation set forth in the adopted allocation Rule.  See the Platform Registration Instructions here to set up your Groundwater Accounting Platform account and claim your parcels.  Please use the following links to find your Sustainability Zone and/or information on your parcel’s land use designation.  

Sustainability Zone Map

Merced County Land Search 

Tools and Resources for Determining historical Consumptive Use for Opt-ins

 MSGSA FINAL Rule and Regulations (Groundwater Allocation Rule)- August 13, 2026