Gualala River Water Banking to Address Low Flows

The Gualala River Watershed includes 740 miles of watercourse draining approximately 181,000 acres in southern Mendocino and northern Sonoma Counties. Like many rivers on the North Coast, the Gualala River is impacted by low flows during the summer months and periods of drought. Although the natural flow regime included periods of low flow, the amount of water and the duration of the low flow season has been exacerbated by human influences such as climate change and surface water diversions. The Mendocino County Resource Conservation District helped to identify sites where infrastructure improvements and development could reduce direct diversions from the Gualala River and it’s tributaries, while improving operational efficiencies, increasing community fire suppression resources, and providing co-benefits to the overall Gualala River ecosystem. In total, the MCRCD coordinated the installation of water storage at three sites:

  • Install a 225,000 gallon, glass-fused-to-steel pre-treatment drinking water tank for North Gualala Water Company (NGWC)
  • Install 40,000 gallons of rainwater catchment/fire suppression water for the South Coast Fire Protection District (SCFPD)
  • Install 18,000 gallons of raw water storage for the Kashia Utility District (Kashia)

The project successfully installed 293,000 gallons of water storage, increasing water supply reliability by 0.87 acre-feet per year.

This project was funded by Proposition 84 funding through the Department of Water Resources. The grant was administered in partnership through the County of Humboldt.