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Groundwater Dependent Ecosystems

Groundwater dependent ecosystems are an important consideration
under the Sustainable Groundwater Management Act

The Sustainable Groundwater Management Act

The Sustainable Groundwater Management Act (SGMA) of 2014 is landmark legislation in California that empowers local agencies, known as groundwater sustainability agencies (GSAs), to manage groundwater resources for current and future social, economic, and environmental benefits.  SGMA establishes a State Policy of Sustainable Local Groundwater Management in the California Water Code.

  • §113 It is the policy of the state that groundwater resources be managed sustainably for long-term reliability and multiple economic, social, and environmental benefits for current and future beneficial uses. Sustainable groundwater management is best achieved locally through the development, implementation, and updating of plans and programs based on the best available science.

Under SGMA, California has an opportunity and obligation to sustainably manage groundwater resources for the benefit of our economy and our environment. As part of achieving these multiple benefits, SGMA includes specific requirements for GSAs to identify the groundwater dependent ecosystems (GDEs) in their basins and consider impacts to GDEs in making groundwater management decisions.

  • §10723.2 Consideration of all Interests of all Beneficial Uses and Users of Groundwater
  • The groundwater sustainability agency shall consider the interests of all beneficial uses and users of groundwater, as well as those responsible for implementing groundwater sustainability plans.  These interests include, but are not limited to, all of the following
    • (e) Environmental users of groundwater
  • §10727.4
  • In addition to the requirements of Section 10727.2, a groundwater sustainability plan shall include, where appropriate and in collaboration with the appropriate local agencies, all of the following:
    • (l) impacts on groundwater dependent ecosystems.

Under the provisions of SGMA, GDEs are “beneficial uses and users of groundwater” and “environmental users of groundwater.”

The Groundwater Sustainability Plan Regulations

In 2016, the California Department of Water Resources adopted Title 23, Division 2, Chapter 1.5, Subchapter 2 of the California Code of Regulations, which is commonly referred to as the Groundwater Sustainability Plan Regulations (GSP Regulations) to detail the process and standards for the development of groundwater sustainability plans under SGMA. The GSP Regulations provide significant guidance about GDEs under SGMA.

Pouring water
© California Department of Water Resources (Dale Kolhe)
Mt. Shasta from the Little Shasta Valley
© Harold E. Malde
Well pumping
© California Department of Water Resources (Kelly M. Grow)
Kayaks on Elkhorn Slough
© The Nature Conservancy (Mark Godfrey)
Irrigated crops
© California Department of Water Resources (John Chacon)

Considering GDEs under SGMA | A Checklist for GSPs

The Nature Conservancy is providing this checklist as guidance for GSAs to adequately address nature in their GSPs, as required under SGMA. Following this checklist does not guarantee approval of a GSP.

View Checklist

The GSP Regulations provide a specific definition of a GDE.

  • § 351(m) “Groundwater dependent ecosystem” refers to ecological communities or species that depend on groundwater emerging from aquifers or on groundwater occurring near the ground surface.”

GDEs are widely considered to be “beneficial uses” of groundwater. The GSP Regulations adopt, by reference, the definitions of Bulletin 118, 2003.

  • § 351. Definitions The definitions in the Sustainable Groundwater Management Act, Bulletin 118, and Subchapter 1 of this Chapter, shall apply to these regulations...

The Bulletin 118, 2003 definitions are contained in the Glossary on Page 214 and “beneficial use” is specifically defined.

  • One of many ways that water can be used either directly by people or for their overall benefit. The State Water Resources Control Board recognizes 23 types of beneficial use with water quality criteria for those uses established by the Regional Water Quality Control Boards.

The referenced 23 types of beneficial uses are specified in Appendix E of Bulletin 118, 2003 on pages 230-240, and they include nine different beneficial uses that fall within the GSP Regulations definition of GDEs.

GDEs are commonly beneficial uses of “interconnected surface water” as defined in the GSP Regulations.

  • § 351(p) “Interconnected surface water” refers to surface water that is hydraulically connected at any point by a continuous saturated zone to the underlying aquifer and the overlying surface water is not completely depleted.

In California, the surface flow in many streams and rivers is supported by groundwater that emerges in springs, seeps and baseflow, which often sustains surface flow during dry periods. This interconnected surface water commonly sustains a wide variety of plants and animals that constitute GDEs, which are, therefore, beneficial uses of the interconnected surface water.

GDEs commonly fall within the GSP Regulations definition of “Water use sectors.”

  • § 351(al) “Water use sector” refers to categories of water demand based on the general land uses to which the water is applied, including urban, industrial, agricultural, managed wetlands, managed recharge, and native vegetation.”

Native vegetation that depends on groundwater is commonly a major component of GDEs.

Specific Reference to GDEs in the GSP Regulations

Whether referred to as groundwater dependent ecosystems, beneficial uses of groundwater, beneficial uses of interconnected surface water or water use sectors, GDEs are frequently addressed in the following sections of the Regulations:

  • § 351         Definitions
  • § 354.8      Description of Plan Area
  • § 354.10.   Notice and Communication
  • § 354.16.   Groundwater Conditions
  • § 354.18.   Water Budget
  • § 354.26.   Undesirable Results
  • § 354.28.   Minimum Thresholds
  • § 354.34.   Monitoring Network
  • § 354.38    Assessment and Improvement of Monitoring Network
  • § 355.4      Criteria for Plan Evaluation
  • § 355.8      Department Review of Annual Reports
  • § 356.2      Annual Reports

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