The Public Trust and SGMA

by Brian Gray

A recent court ruling about the Scott River has prompted questions about SGMA and the public trust doctrine.

In a recent decision in litigation over flows and salmon survival in the Scott River system, the California Court of Appeal has ruled that groundwater pumping that diminishes the volume or flow of water in a navigable surface stream may violate the public trust. The public trust does not protect groundwater itself. “Rather, the public trust doctrine applies if extraction of groundwater adversely impacts a navigable waterway to which the public trust doctrine does apply.” The court also concluded that the Sustainable Groundwater Management Act (SGMA) does not preempt or preclude independent application of the public trust to groundwater pumping, finding “no legislative intent to eviscerate the public trust in navigable waterways in the text or scope of SGMA.”

These interpretations follow from both hydrology and law. If groundwater extraction diminishes stream flows and jeopardizes public trust uses—which include water quality, fish and wildlife, recreation, and other instream uses—it should be treated the same as surface diversions that have similar effects. This is also consistent with the California Supreme Court’s landmark decision in the Mono Lake case. In National Audubon Society v. Superior Court (1983), the court recognized the public trust as a limitation on Los Angeles’ diversions of water from nonnavigable tributaries, because those diversions harmed public trust uses in the navigable lake downstream.

Moreover, if the public trust was not displaced by the modern statutory water rights system generally, as the Supreme Court held in Audubon, it should not be displaced by a more specific law such as SGMA—unless the legislature manifested its intent to preempt the public trust or other aspects of California water rights law. Indeed, SGMA says just the opposite, declaring that nothing in the statute or any groundwater sustainability plan “determines or alters surface water rights or groundwater rights under common law or any provision of law that determines or grants surface water rights.”

The Scott River Decision and SGMA Implementation

Although the court of appeal’s opinion makes clear that the public trust applies independently of SGMA, the Scott River decision nevertheless will influence the formulation and implementation of groundwater sustainability plans (GSPs). At a minimum, the decision should focus groundwater sustainability agencies and groundwater users on SGMA’s directives to avoid “depletions of interconnected surface water that have significant and unreasonable adverse impacts on beneficial uses of . . . surface water” and to address the effects of pumping on groundwater dependent ecosystems in their sustainability plans. (Water Code §§ 10721(x)(6) & 10727.4(l)) The overriding concern of most GSAs will be to manage demand and available recharge to achieve sustainable aggregate pumping levels by their members as required by SGMA. This presents a risk that they will downplay other aspects of sustainability, including prevention of injury to public trust uses. The Scott River decision changes this dynamic.

The decision also affects the timeframe for remediating harm to public trust uses of hydrologically connected, navigable rivers or lakes. SGMA requires GSAs to develop and implement plans that achieve sustainability within a 20-year (or longer) period.  Under the new decision, however, a claim to enjoin groundwater pumping that impairs the public trust may be brought at any time. In adjudicating these claims, the State Water Board and the courts are likely to consider—and give some deference to—the GSP’s strategy and timeline for addressing harm to surface resources. But neither would be bound or limited by the terms of the sustainability plan.

Public trust claims are subject to different standards than those that apply under SGMA however, and these differences cut in both directions. For example:

  • The public trust only protects navigable rivers and lakes. Therefore, the Scott River decision will not affect groundwater pumping that harms wetlands or nonnavigable streams—unless the harm manifests itself downstream in a navigable body of water. In contrast, SGMA’s directives extend to all types of groundwater extraction and surface water resources.
  • In Audubon, the state Supreme Court held that the public trust doctrine requires water users to protect public trust uses to the extent feasible. This requires an assessment of the feasibility of restoring and protecting the surface resource, as well as consideration of the water users’ alternative sources of supply, demand reduction capabilities, efficiency improvements, and cost considerations. In contrast, SGMA’s sustainability mandate does not include a feasibility criterion.
  • The public trust requires restoration and maintenance of groundwater levels and surface water flows as needed to afford reasonable protection of public trust uses. By comparison, SGMA provides that GSAs are not required to address “undesirable results” that occurred before January 1, 2015, such as harm to beneficial surface water uses. No such baseline or statute of limitations applies to public trust claims.

The Scott River Decision and Water Management

With these principles in mind, the Scott River decision will likely play out in mixed ways across California.

First, there are many watersheds where groundwater discharges feed headwaters and tributaries or the groundwater table supports the rivers themselves. This occurs throughout the Sacramento-San Joaquin River system, in many coastal streams, and in the rivers of the Tulare Basin above the rim dams where more than two-thirds of stream discharges come from groundwater. When river flows run low and threaten public trust uses, the Scott River decision will extend remediation and protection responsibilities to surface diverters and groundwater extractors alike.

Second, hydrologic studies have demonstrated that, in some systems, groundwater pumping is a significant cause of stream flow reduction that harms fish. These include: the Cosumnes River, where late season diversions and groundwater pumping imperil fall-run Chinook salmon; the Russian River, where pumping from aquifers that support the river and its tributaries has placed coho salmon in jeopardy; and the Scott River itself, where groundwater overdraft has reduced late summer and fall stream flows and raised surface water temperatures to the detriment of Chinook salmon, coho, and steelhead. The public trust is likely to play a significant role in these systems.

Third, there are regions where the hydrologic connection between groundwater and navigable rivers and lakes was lost long ago. On the valley floor of the Tulare Basin, for example, sustained groundwater overdraft for many decades has lowered the groundwater table by hundreds of feet. Because restoration of the hydrologic connection would require drastic long-term reductions in groundwater extraction and water use, it is unlikely that the State Water Board or the courts would find that such restoration is feasible under the standards set forth in Audubon.

Finally, there are systems where local water users and other interested parties are working to restore and protect stream flows, wetlands, riparian vegetation, and other groundwater dependent ecosystems. Although many of the groundwater dependent ecosystems in these systems do not qualify as navigable waters, they often feed into and support navigable rivers. To the extent that pumping adversely affects public trust uses in such surface waters, groundwater extractors may be called on to contribute to system-wide solutions. Examples include: the Oxnard Groundwater Subbasin, where the Fox Canyon Groundwater Management Agency is working with The Nature Conservancy to improve water supplies for six groundwater dependent ecosystems that are tributary to the Santa Clara River; and the Los Angeles River system, where the City of Los Angeles is working with Friends of the LA River to revitalize the river by removing concrete, restoring riparian zones, controlling stormwater inflows, and creating infiltration areas to improve groundwater conditions that support the river.


The Scott River decision places new responsibilities on GSAs and groundwater users, and it increases the legal leverage of those who seek to restore and protect groundwater dependent rivers and ecosystems. Yet, the decision need not lead to more litigation.

Rather, GSAs with responsibility over groundwater that has (or feasibly could have) a hydrologic connection with surface water resources should incorporate public trust analysis into their sustainability plans. They should work with experts in groundwater-surface water hydrology and ecological sciences, and they should partner with pubic trust advocates. The Fox Canyon and LA River collaborative restoration programs are useful examples.

Incorporation of public trust analysis into relevant GSPs offers several advantages over public trust litigation. Sustainability plans are more comprehensive, because they must include evaluation of the effects of groundwater pumping on all beneficial uses of surface water and groundwater dependent ecosystems, not just on public trust uses of navigable waters. The plans also can provide a vehicle for integrated management that includes floodplains, wetlands, riparian zones, and connected surface waters, as well as regulation of groundwater pumping and deployment of surface water recharge. And GSP formulation can be a collaborative process that engages all interested parties, rather than pitting them against one another. Indeed, every successful public trust lawsuit to date has culminated in a negotiated settlement that folds the public trust remedies into a broader, multifaceted restoration and long-term management program.

The State Water Board or the Department of Water Resources should facilitate these studies by providing guidance on protecting and remediating harm to public trust uses within the framework of groundwater sustainability plans. The Department of Fish and Wildlife and DWR should offer technical support. DWR also should make clear that its formal GSP review will include evaluation of the plan’s analysis of the effects of groundwater extraction on waters protected by the public trust and its strategy for addressing harm to public trust uses.

Brian Gray is a Senior Fellow at the Public Policy Institute of California Water Policy Center and a Professor Emeritus at UC Hastings.

Further Reading

Belin, Alletta. 2018. Guide to Compliance with California’s Sustainable Groundwater Management Act. Water in the West, Stanford University.

California Department of Water Resources. 2018. SGMA Groundwater Management: Best Management Practices and Guidance Documents.

Alida Cantor, Dave Owen, Thomas Harter, Nell Green Nylen, and Michael Kiparsky. 2018. Navigating Groundwater-Surface Water Interactions under the Sustainable Groundwater Management Act. Center for Law, Energy & the Environment, UC Berkeley School of Law.

Jan Fleckenstein, Michael Anderson, Graham Fogg, and Jeffrey Mount. 2004. “Managing Surface Water-Groundwater to Restore Fall Flows in the Cosumnes River.Journal of Water Resources Planning and Management. Vol. 130, No. 4, pp. 301-10.

Richard Frank. 2018. “California Court Finds Public Trust Doctrine Applies to State Groundwater Resources. Legal Planet, Aug. 29, 2018.

Brian Gray. 2012. “Ensuring the Public Trust. U.C. Davis Law Review, Vol. 45, pp. 973-1019.

Jeanette Howard and Matt Merrifield. 2010. “Mapping Groundwater Dependent Ecosystems in California.PLOS One, June 23, 2010.

Melissa Rohde, Sandi Matsumoto, Jeanette Howard, Sally Liu, Laura Riege, and E. J. Remson. 2018. Groundwater Dependent Ecosystems Under the Sustainable Groundwater Management Act: Guidance for Preparing Groundwater Sustainability Plans. The Nature Conservancy, San Francisco.

The Nature Conservancy. 2018. Groundwater Resource Hub: Understanding and Managing Groundwater Dependent Ecosystems.

This entry was posted in California Water, Groundwater and tagged , , , , . Bookmark the permalink.

7 Responses to The Public Trust and SGMA

  1. Jennifer Bowles says:

    Typo in Brian’s first name. FYI.

    Sent from my iPhone

  2. Dan Ray says:

    Similar decision recently in Mn, where court determined State Dept of Natural Resources had failed in duty to protect White Bear Lake from adverse effects of groundwater pumping, which had significantly lowered lake levels. Guess great minds think alike!

  3. gymnosperm says:

    “First, there are many watersheds where groundwater discharges feed headwaters and tributaries or the groundwater table supports the rivers themselves.”

    This is an important distinction. Groundwater distribution and movement is complex and poorly understood. The asymmetric subsidence of the western and eastern sides of the lower San Juaquin Valley in response to roughly equal extraction comes to mind. It is also increasingly apparent that groundwater is a large and unresolved factor in global sea level…

  4. J Rizzi says:

    Study adding deep Ponds in the river. Adding Deep ponds adds ground water by adding surface area to water heading down stream. Adding 5 Deep ponds per mile will also cool water and keep cold water colder longer, which is great for fish. Ponds are also ideal for fish, ask any fisherman where to fish along a river. Lets consider solving natures issues with our own.

  5. Pingback: The folly of unimpaired flows for water quality management | California WaterBlog

  6. Pingback: Backdoor Conjunctive Management: How the Public Trust Doctrine Seeped into Aquifers in California - Schroeder Law Offices

Leave a Reply