Key Points

• The public trust requires that permitting agencies consider whether the use allowed under a permit will affect public trust resources like surface water
• Sonoma County adopted a public trust review ordinance for new groundwater wells, which intended to protect public trust uses of surface water when feasible
• But a trial court struck the ordinance down because the County did not rely on substantial evidence showing how the ordinance will protect those public trust uses
• While the case involves a novel issue over the public trust doctrine, its holding is not precedential

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The public trust doctrine is a concept drawn from the Roman Empire. Though ancient, it has experienced a recent resurgence in how California manages natural resources like water.

As applied to water, the doctrine recognizes that the public has a right to use surface water. Those uses include commerce, navigation, recreation, habitat for wildlife, and other ecological purposes. Given the public’s interest in using those resources, California and its local governments hold them in “trust.” As the public’s “trustee,” the government is dutybound to protect those public uses when feasible.

That duty arises often when an agency grants a permit or transfers property affecting those resources. And as we have explained, the doctrine’s scope can go beyond surface waters. For instance, when issuing a permit to extract groundwater that can affect a river or lake, the agency must consider those public trust resources before granting the permit. How it decides to consider those resources, however, is left to the agency’s discretion. 

A few years ago, Sonoma County was sued for allegedly issuing groundwater well permits without considering their impact on public trust resources. The County settled the case, imposed a moratorium on new groundwater well permits, and later adopted a groundwater well ordinance addressing its public trust obligations.

The ordinance is novel. It identifies a “public trust review area” within which applications for groundwater well permits require “discretionary public trust review.” Not all wells are the same, however. So the ordinance exempts certain classes of groundwater wells, like wells using fewer than two acre-feet of groundwater per year. This process, the County explained, tried to achieve the difficult task of balancing many competing interests in public trust resources. Even if the result was not perfect, the County emphasized that it enjoys discretion to decide how best to balance those competing interests.

And yet the County was sued again. On August 21st, a trial court in Russian Riverkeeper v. County of Sonoma struck down the public trust review ordinance. There is no real question that the County’s ordinance did not ignore public trust resources. So is this some expansion of the public trust doctrine?

Not quite. The trial court agreed that the County enjoys discretion in how it satisfies its public trust duty. But the County abuses that discretion when, as the court explained, it has not developed substantial evidence showing how its ordinance will protect the public trust. An agency may “anticipate” or “expect” an ordinance to protect the public trust, but the trial court expects more: it must have substantial evidence showing how it will do so. And it should quantify its objectives so the County, the public, and the reviewing court may determine whether the ordinance is protecting public trust resources.

What evidence and measurable objectives the County should have considered—and what factors it should have considered in developing either—remains an open-ended question. The trial court acknowledged that the public trust doctrine does not require agencies to consider any specific factors. But what relevant factors an agency must consider in a given context will be a moving target, “which fluctuate on a case-by-case basis.”

While the holding yields some uncertainty in how agencies and courts should administer the public trust doctrine, we pause to focus on the holding’s limited impact. The trial court struck down the County’s ordinance because it was unsupported by substantial evidence. Even under that ruling, how agencies discharge their public trust duty remains in their discretion. And to be sure, the trial court order applies only to the County of Sonoma; it has no precedential value other than how it is applied to the County.

As the public trust doctrine continues to evolve, agencies and permittees must remain apprised of these developments. If you have any questions or concerns about how the public trust doctrine and groundwater affect you, please contact our Water Law attorneys.