Farmers Water District Groundwater Sustainability Plan Delta-Mendota Subbasin

The Sustainable Groundwater Management Act (SGMA) was signed into law in 2014 for the purpose of protecting California’s groundwater resources. SGMA requires all high and medium priority basins to develop Groundwater Sustainability Plans (GSP) to prevent overdraft and achieve sustainability in the utilization of groundwater resources. The Delta-Mendota Subbasin (Basin 5-022.07 in the California Department of Water Resources (DWR) Bulletin 118) (Subbasin) is a high priority Subbasin that has been assigned a critical overdraft designation by DWR. The Subbasin consists of 23 Groundwater Sustainability Agencies (GSA) who together created six individual GSA groups, each preparing a GSP in a coordinated manner as required by SGMA. Farmers Water District elected to form a GSA on June 14, 2016 in order to represent the interest of local landowners in the District in the development of a GSP with FWD designated as a Management Area in GSP.

This GSP includes a description of groundwater conditions and basin settings of the Subbasin that is common to all six of the GSPs developed for the Delta-Mendota Subbasin in addition to describing the hydrogeologic conditions and management practices in the area of FWD. It also contains the steps that will be taken to achieve sustainability over the next 20 years by preventing undesirable results by monitoring for the following sustainability indicators as defined by SGMA:

• Chronic Lowering of Groundwater Levels

• Reduction in Groundwater Storage

• Degraded Water Quality

• Subsidence

• Depletion of Interconnected Surface Water

• Seawater Intrusion

All but seawater intrusion applies to FWD, and each applicable sustainability indicator will be addressed in this GSP and is integrated into the Subbasin-wide and FWD monitoring program. Measurable objectives and minimum thresholds have been set for each sustainability indicator based on projected hydrologic conditions through the use of a numerical groundwater flow model. This GSP, in coordination with the five other GSPs for the Subbasin, will be implemented and result in the sustainable use of groundwater resources for all beneficial users in FWD and the Subbasin.