Annual reports on groundwater conditions in Napa County have been developed since 2014. Starting in 2017 these reports included special consideration of the Napa Valley Subbasin to document current conditions and provide an update on how the Subbasin is meeting goals related to the Sustainable Groundwater Management Act (SGMA) and State regulations governing groundwater sustainability plans (GSPs).
Annual reporting is required under SGMA and GSP regulations. Reports must be submitted to the Department of Water Resources by April 1 of each year following adoption of a GSP.