Create an Account - Increase your productivity, customize your experience, and engage in information you care about.
A Groundwater Sustainability Plan (GSP) is the state-mandated plan to sustainably manage groundwater. Each GSP will contain an assessment of each basin, measurable objectives that are specific, and quantifiable goals for the maintenance or improvement of specified groundwater conditions that lead to achieving the sustainability goal for the basin. A GSP must also include any necessary monitoring, management, enforcement, and other requirements to achieve and maintain sustainability.
Show All Answers
Required elements of a GSP are:
A description of the physical setting and characteristics of the aquifer system underlying the basin, including:
Measurable objectives to achieve the sustainability goal in the basin within 20 years of the implementation of the plan, including interim milestones.
A planning and implementation horizon
Information about the following, as applicable:
More detailed requirements are identified in Section 10727 of the California Water Code.
Section 8 of the GSP will address future development and population change in the context of the water budget analysis, using best-available data. Projections of future development in the Subbasin will be incorporated to provide consistency with local land use agency assumptions and projections. Projected water budget results are planned to be available in Summer 2021. For more information, see the Section 8 outline provided as part of the GSP Annotated Outline included in the GSPAC July 9, 2020 meeting packet, at pages 16-17 and more recent updates of the GSP Annotated Outline provided through the online surveys for comments on the Draft GSP Sections.
SGMA and DWR GSP Regulations require that GSPs include a water budget that quantifies inflows to, outflows from, and changes in storage for the relevant groundwater basin or subbasin. For this reason, the water budget presented in the GSP will address the Napa Valley Subbasin. However, the County and technical team recognize the potential for land uses adjacent to the Subbasin to affect the Subbasin water budget and have expanded the Napa Valley Integrated Hydrologic Model (MODFLOW-OWHM) domain to include areas adjacent to the Napa Valley Subbasin including the Milliken-Sarco-Tulucay and Carneros Subareas as well as other areas of developed land use that are contiguous with the Subbasin. These additional areas include areas served by the City of Napa potable water system west of the Subbasin, the Yountville Veterans Home, and agricultural lands contiguous with the Subbasin boundary.
The Napa Valley Subbasin is a high priority subbasin and the Groundwater Sustainability Plan (GSP) must be submitted to the California Department of Water Resources (DWR) by January 31, 2022.
The Napa Valley Subbasin GSP and the Napa Valley Drought Contingency Plan (DCP) are separate but complementary planning efforts. Although they are independent efforts, opportunities for integration between the plans are expected to be available.
The Napa Valley DCP is a voluntary planning effort focused on water supply reliability for local water supply agencies. The DCP is being developed as part of the U.S. Bureau of Reclamation’s drought response program which aims to help local water supply agencies better understand and prepare for droughts and mitigate drought impacts. Completion of the DCP provides the opportunity for agencies to competitively compete for future implementation funding for drought resiliency projects described in the DCP. The Napa Valley DCP is currently under development in cooperation with Napa County, Napa Sanitation District, the Cities of Calistoga, St. Helena, Napa, and American Canyon, and the Town of Yountville.
Both planning efforts will propose projects and management actions to achieve their respective goals. While the two efforts are on slightly different timelines, the Draft Napa Valley DCP is expected to be available in Spring 2021, while the Draft GSP will be available in September 2021, there is opportunity for collaborating on potential joint projects that address both groundwater and drought resiliency.