Eel River Valley Groundwater Basin Resources

Eel River Valley Groundwater Sustainability Plan

Eel River Valley GSP Executive Summary (PDF 407 KB)

Eel River Valley GSP (January 29, 2022) (PDF 6.59 MB)

Figures (PDF 47.7 MB)

Elements Guide (excel workbook download)


Other Documents


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Groundwater Sustainability Agency Administration  

Sustainable Groundwater Management Grant Application (November 2019)

On November 14, 2019 Humboldt County submitted a grant application to DWR as a proxy for the future Eel River Valley GSA to obtain a planning grant for the Eel River Valley Groundwater Sustainability Plan and Monitoring Well Installation Project. Formation of a GSA and development of a GSP is required because DWR disapproved the submitted Groundwater Sustainability Plan Alternative (see below). The proposed project includes stakeholder outreach and engagement, data collection and analysis, enhancement of the hydrogeological conceptual model and water budget, numerical modeling of the groundwater-surface water system, and document preparation. In January 2020, the project was included on DWR’s draft list of proposed funding awards. The grant agreement was executed in May 2020. The project will be completed by January 2022.

Groundwater Sustainability Plan Alternative Submittal (December 2016 - November 2019)

SGMA contained provisions for local agencies to submit Groundwater Sustainability Plan Alternatives (GSP Alternatives) by January 1, 2017, if there was evidence demonstrating that the basin had been managed sustainably for at least 10 years prior to the adoption of SGMA. GSP Alternatives are more streamlined plans and do not require the formation of a Groundwater Sustainability Agency.

In 2016, Humboldt County was awarded a Prop. 1 planning grant to perform an initial assessment of the Eel River Valley groundwater basin. Based on the data and information gathered in this assessment, Humboldt County concluded that there was sufficient evidence demonstrating that the basin had been managed sustainably for at least 10 years. On December 30, 2016, Humboldt County submitted a GSP Alternative to DWR for review.

On July 17, 2019, DWR provided a letter and staff report stating that DWR intended to disapprove the submitted GSP Alternative for the Eel River Valley groundwater basin, for the following reasons:

  • The GSP Alternative did not demonstrate that objective management criteria had been in place for 10 years;
  • The GSP Alternative did not sufficiently demonstrate the absence of undesirable results;
  • A quantitative estimate of sustainable yield had not been provided; and
  • The GSP Alternative did not quantify the impacts of groundwater use on surface water systems and determine at what point they are significant and unreasonable.


Basin Prioritization

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