Low Flows in the Eel River Require Action to Protect Public Trust Values

Flows in the mainstem Eel River are at historically low levels. In fact flows are lower now than they were in 2014 when the river disconnected in the fall and left migrating Chinook suffering from elevated levels of disease. This is why we asked the Humboldt County Supervisors this week to take immediate action and pass an emergency ordinance which would allow them to curtail groundwater pumping to preserve surface flows. Read our letter below.

Letter to Humboldt County Board of Supervisors

RE: Low flows in the lower Eel River will require the County act to protect public trust values


Tuesday, June 15, 2021

Dear Humboldt County Supervisors:

The Eel River is facing one of the most challenging years in the county’s history. Below-average rainfall and above-average temperatures over the last two years have left flows in the Eel at historically low levels, threatening critical public trust values including fisheries and recreation. While we have just received a bit of very welcome rain on the coast, flows in the Eel River remain the lowest on record. (The only time recorded flows in the mainstem Eel River have been lower at this time of year was in 1924, when the Lake Pillsbury reservoir behind newly constructed Scott Dam at the top of the mainstem Eel River was being filled for the first time.)

Figure 1 plots hydrographs of mean monthly flow on the Eel River at Scotia for the six driest years for the 104-year period 1917 through 2020. A hydrograph for the first half of the current water year (2021) is also plotted as the red line. The historic hydrographs indicate that after the wet season and through the summer, the flow rates on the Eel River recede at a consistent rate. This is indicated by the parallel nature of the historic hydrograph limbs between April and August. This phenomenon allows a reasonable prediction for this summer’s flow rates as depicted by the dashed red line portion of the 2021 hydrograph. This also illustrates that Eel River flows during the upcoming summer will be very similar to those experienced in 1977 and 2014 — again, the only time recorded summer flow rates were lower in the mainstem Eel was in 1924, when the upper Eel was being impounded.

In the fall of 2014, when flows were higher in June than they are this year, the lower Eel River disconnected downstream of Fortuna, immediately above the reach where the tides affect the river’s height. At the time, it was evident that groundwater pumping throughout the lower Eel River was still in full swing, and probably even proceeding at a greater rate than usual because the late summer had been so warm. Unfortunately, the chinook salmon run holding at the mouth of the Eel was unable to ascend the river. Many of those fish died from outbreaks of disease associated with high water temperatures.

As the Court of Appeals for the Third Appellate District affirmed in a 2018 case regarding groundwater extraction which impacted surface flows in the Scott River, Environmental Law Foundation v. State Water Resources Control Board, 26 Cal.App.5th 844, groundwater resources that are connected to the surface water flows of navigable waterways are subject to California’s public trust doctrine. The court held the public trust doctrine “protects navigable waters from harm caused by extraction of groundwater, where the groundwater is so connected to the navigable water that its extraction adversely affects public trust uses.”

The County has a duty to ensure that its programs are designed and implemented to take into account the public trust and, wherever feasible, protect the trust. The County “shares responsibility for administering the public trust and ‘may not approve of destructive activities without giving due regard to the preservation of those resources.’” (26 Cal.App.5th at 868 (quoting Center for Biological Diversity, Inc. v. FPL Group, Inc. (2008) 166 Cal.App.4th 1349, 1370, fn. 19.) This duty extends to the County’s issuance and oversight of well permits pursuant to the Humboldt County Code § 631-1, et seq.

As currently written and implemented, the County’s well permitting program fails to comport with the County’s duty to employ its powers to ensure that, to the extent feasible and consistent with the public trust, pumping is curtailed from wells that will contribute to the extraction of water from the lower Eel River and its disconnection from its estuary this coming summer and early fall. Currently, it does not appear that the County has taken into account impacts to the Eel River’s public trust values when issuing well permits. FOER’s review of the well permitting procedures also indicates that the County’s program poses an improper obstacle to the County’s public trust duties and the absence of well permit reopening or enforcement provisions in the County Code violates the County’s duty to ensure the public trust is taken into account by those well permit approvals.

We strongly suspect that groundwater pumping in the lower Eel River groundwater basin will adversely affect the public trust values in surface flows by contributing to and extending the duration of the river’s disconnection this summer and early fall. The county’s own data show groundwater pumping lowers the aquifer water table 0.5- to 0.8-feet immediately adjacent to the river in the lower Van Duzen River portion of the basin. This increases the rate of river depletions to the aquifer and reduces the river flow rate.

Under ELF v SWRCB, Humboldt County “‘shares responsibility’ for administering the public trust” with the state, and thus has affirmative duties, first to consider the public trust, and second to restrain groundwater extraction in the lower Eel groundwater basin, where such extraction will harm public trust values in surface flows.

In ELF v SWRCB, Siskiyou County both denied that it had any obligation to prevent harms to surface flows, and argued the Sustainable Groundwater Management Act preempted plaintiffs’ public trust claims. The Court of Appeals rejected both arguments, and the California Supreme Court denied review. Thus, the question your Board faces is not whether the county’s pending Groundwater Sustainability Plan will be accepted by the state Department of Water Resources as sufficient under the Sustainable Groundwater Management Act. It is whether the Board will act to protect the public trust values in the lower river threatened, in part, by extraction of groundwater that is connected to surface waters.

We are writing today to urge and request your Board take immediate, specific actions to ensure Humboldt County can instruct groundwater users to reduce their pumping as necessary to sustain public trust values in connected surface waters beginning this summer. Humboldt County presently lacks an ordinance under which groundwater users can be required to reduce their pumping as necessary to protect the public trust in hydrologically connected surface waters. We strongly urge your Board to pass such an ordinance on an emergency basis. The county will also need to consider how it wishes to assess, balance and protect the public trust values in surface flows that may be affected by groundwater pumping.

As well, we urge Humboldt County to proceed with its current SGMA data-gathering efforts in ways that will most effectively demonstrate any connections that do exist between surface flows and groundwater extraction in the lower Eel River groundwater basin. We are concerned the present modeling effort will obscure rather than illuminate those relationships.

Thank you for your attention to these important matters.

Alicia Hamann
Executive Director


FIGURE 1: Average monthly flow (cfs) at the USGS Eel River flow gauge (11477000) at Scotia, CA.