Eel River Valley Groundwater Basin

Groundwater Sustainability Plan Timeline

  1. 2014
  2. 2015
  3. 2016-2019
  4. 2020-2022
  5. 2022-2042

Groundwater Sustainability Plan Purpose

The purpose of the Groundwater Sustainability Plan is to ensure high quality and abundant groundwater resources for human consumption, agricultural irrigation, and environmental services without causing significant and unreasonable adverse impacts (undesirable results). The work to develop the plan includes data collection and analysis to characterize the groundwater basin (including interactions with surface waters), develop reliable estimates of water budgets, and quantify the sustainable yield. This work will create computer modeling tools to investigate the presence or absence of undesirable results associated with groundwater pumping and support the development of sustainable management criteria.

Basin Background

The Eel River Valley groundwater basin is adjacent to the Pacific Ocean in Humboldt County, California, and experiences a cool maritime climate and substantial winter precipitation. The basin boundary encompasses approximately 72,957 acres and 21,558 residents, with nearly half of this population residing within the City of Fortuna.  In addition to agriculture and timber resources, the City of Fortuna, the City of Ferndale, the City of Rio Dell, and the unincorporated communities of Loleta, Carlotta, Hydesville, and Scotia occupy the basin.  The Eel River Valley Groundwater Basin contains five (5) census designated places which are recognized by California Department of Water Resources as Economically Distressed Areas: Ferndale, Loleta, Fortuna, Scotia, and Rio Dell.  

Groundwater is supplied for general household use, agriculture production, and industrial or business use. Groundwater suppliers in the basin include: private domestic and agricultural wells, municipal wells, and public water systems. The basin is bisected by the main stem Eel River and its tributary, the Van Duzen River, both of which provide habitat for anadromous salmonids and other fish and aquatic species. The coastal basin discharges to the Pacific Ocean near Loleta. Tidal influences have been recorded in Eel River water studies up to five miles upstream of the river mouth (SHN, 2019). A study performed in 2016 by the Humboldt County Resource Conservation District, and included in the Eel River Valley Basin Eel River Valley Groundwater Sustainability Plan Alternative Submittal found on the Resources tab, estimated that approximately 13,558 acres of agricultural lands were irrigated using groundwater, of which more than 85% was applied to grazed pasture or hay crop production for livestock.  Other common basin crop types include corn, quinoa, and cannabis. 

The basin provides for multi-use opportunities for outdoor recreational enthusiasts.

Eel River Basin Map

Map of the Eel River Basin

The image above shows the Eel River watershed boundary (purple) across Humboldt, Trinity, Mendocino, Glen, and Lake Counties. The branches of the Eel River and its tributaries are shown by the blue lines. The Eel – Russian River basin divide is shown by the red line. The Eel River Valley basin is located entirely within Humboldt County, highlighted in light blue.

Eel River Valley Water Suppliers Map


The map above shows the boundaries of the various municipal water suppliers within the Eel River groundwater basin.

Funding and Project Partners