Napa County Highlights Subsurface Water Sustainability For Groundwater Awareness Week

Press release from the Napa County Government:

NAPA, CA — Napa County joins the National Ground Water Association and the Groundwater Foundation in celebration of Groundwater Awareness Week March 10-16 to highlight the responsible development, management, and use of groundwater across the country.

Groundwater is a critical component of the water supply for Napa County and the state, serving as a resource for many different industries and uses, including farms, urban and rural communities, and ecosystems. The Napa Valley Subbasin spans 45,900 acres extending from the intersections of highways 221 and 12 north towards Calistoga and has been identified as a high-priority subbasin. Whether it is a wet or dry year, the Napa Valley Subbasin serves as an important source of water for the county since agricultural and other users have few other water sources. In 2023, approximately 15,270 acre-feet of water was pumped from the subbasin (one acre-foot equals about 326,000 gallons).

As California continues to experience climate-driven weather extremes, it’s crucial to understand groundwater conditions and manage groundwater so it is available for future generations. Since the passage of the Sustainable Groundwater Management Act in 2014, and the approval of the County’s Groundwater Sustainability Plan (GSP) by the Department of Water Resources in January 2023, the Napa County Groundwater Sustainability Agency (GSA) has been developing three workplans, which seek to address implementation components within the GSP to achieve sustainability across the Napa Valley Subbasin. The workplans seek to study the interconnection between surface water and groundwater to protect Napa’s rich ecological diversity, and to collaborate more closely with vineyards, wineries, and other water users to increase water conservation practices to preserve precious groundwater across the Subbasin.

Additionally, the GSA is working to expand its groundwater monitoring network and fill critical data gaps to understand groundwater trends near the Napa River and several tributaries. To better help the community understand groundwater level trends and conditions across the subbasin, the GSA has recently updated its interactive public web map with groundwater levels collected from around the county. Explore the data to see how water levels fluctuate.

“Groundwater Awareness Week is an opportunity to learn and reflect on how we as a county are ensuring the sustainability of groundwater for years to come,” said Chair of the Napa County Board of Supervisors Joelle Gallagher. “We’ve made great progress with the Groundwater Sustainability Plan through the development of workplans and public input, and it brings us one step closer to securing the long-term sustainability of the Napa Valley Subbasin.

Management of the Napa Valley Subbasin is the responsibility of the Napa County GSA. The GSA is advised by a five-member panel of technical experts called the Technical Advisory Group. The public is invited to participate in their meetings on the second Thursday of every month at 1:30 p.m. Meeting agendas and materials can be found here. To join the groundwater email list for notification of meetings, click here.

To learn more about groundwater, visit Napa County's Groundwater Web Page, the SGMA website, and this interactive StoryMap.

For more information, please contact Natural Resources Conservation Manager Jamison Crosby at jamison.crosby@countyofnapa.org.

This press release was produced by the Napa County Government. The views expressed here are the author’s own.