May 27, 2020

Supreme Court ruling finds old, new middle ground on Clean Water Act's application to groundwater

[Cross-posted from California WaterBlog]

By Thomas Harter, Steph Tai and Karrigan Börk

In 1972, the U.S. Clean Water Act (CWA) created a permit system for point source discharges to navigable waters of the United States – rivers, lakes, and coastal waters – with the goal of restoring and protecting their water quality. Typically, these permits are issued by the U.S. EPA or through state agencies to dischargers of wastewater, e.g., from urban and industrial wastewater treatment plants and to other dischargers of potentially contaminated water that reach streams by a pipe or similar conveyance. The goal was to provide some degree of regulatory oversight over such discharges.  In California, the State Water Resources Control Board implements the federal Clean Water Act using its authority under the Porter-Cologne Water Quality Control Act (Water Code, §13000 et seq.). Under the CWA, neither EPA nor the states are required to issue permits for pollutant discharges into groundwater or to nonpoint source dischargers.

In April, the Supreme Court decided on a case involving discharge from a wastewater reclamation facility owned and operated by the County of Maui.  In this case, the facility discharged 3 to 5 million gallons of treated wastewater per day into four injection wells about half a mile from the ocean.  Recent research showed that much of the injected waste eventually discharges to the ocean. Environmental groups sued the county for not obtaining a CWA permit, arguing that point source discharge of pollutants that eventually reach surface water is governed under CWA. All sides agreed that the case at hand involved a point source of pollutant discharge and that the pollution eventually reached the ocean. The disagreement was whether the CWA requires the permit only if the pollutant discharge is directly into surface water, as argued by the defendants (a “bright-line test”). Environmental groups argued that even if the pollutant discharge is via groundwater to surface water, the CWA permit must be obtained. The district court and the Ninth Circuit court ruled in favor of the plaintiffs. The Ninth Circuit court held that permits are required when “pollutants are fairly traceable” from the point source to surface water.

In its final 6-3 decision, the Supreme Court majority now rejects both sides’ arguments as too extreme and returned the case to the lower courts with further guidance.  On the “bright-line test”, Justice Breyer, writing for the majority, wrote “we do not see how Congress could have intended to create such a large and obvious loop hole in one of the key regulatory innovations of the Clean Water Act.”  On the “fairly traceable” approach, the opinion stated that such interpretation “would require a permit in surprising, even bizarre circumstances.”

Instead, the Court decision introduces the concept of a “functional equivalent of a direct discharge” as a guideline for when a point source discharge must obtain a permit. It cites the case of an injection well receiving pollutant discharge that then travels a few feet through groundwater into navigable waters as a clear case of “functional equivalent” to direct discharge. But it rejects the notion that such a “functional equivalent” exists in a case with “100 year migration of pollutants through 250 miles of groundwater to a river” and “likely does not apply” if “the pipe ends 50 miles from navigable waters”. The Court acknowledges that the concept of “functional equivalence” as the Court’s guideline leaves many point source discharges to groundwater somewhere between these extreme cases.  It relegates consideration of those cases back to regulators and lower courts, suggesting they consider the various groundwater flow and transport factors underlying individual cases – travel time and distance in particular, but also soils and geology, geochemical reactions, the locations where pollutants subsequently enter navigable waters, and “the degree to which the pollution (at that point) has maintained its specific identity.”

Importantly, the majority opinion does not expect a “vastly” expanded scope of the CWA, such that permits would be required, e.g., for the country’s 20 million septic systems. It does so in two ways: by emphasizing (and affirming) the long history of CWA implementation, which has, at times, required permits even if pollutant discharge was via groundwater into surface waters, but not under other circumstances. And, secondly, both the majority and dissenting opinions repeatedly underscore the important role and sovereignty of states in regulating discharges to groundwater and nonpoint source pollution (groundwater pollutant discharge to surface water is sometimes considered nonpoint source pollution of surface water).

The decision will not make it easier than in the past for either regulators or lower courts to make their determinations as to whether a point source pollutant discharge to groundwater that eventually affects surface water is subject to a CWA permit. But the decision sides squarely with the use of science. And it shows a remarkable acknowledgement of hydrologic sciences and the interconnectedness of surface water and groundwater: “Virtually all water, polluted or not, eventually make its way to navigable water. This is as true for groundwater.” Perhaps this statement missed the nuance that some groundwater, particularly in the western U.S., will instead be pumped by wells onto crops or pulled by plant roots from the water table to be evapotranspired into the atmosphere. But it underscores that the court made its decision knowing and applying hydrologic science. “Given the power of modern science, The Ninth Circuit’s limitation, ‘fairly traceable’, may well allow EPA to assert permitting authority over the release of pollutants that reach navigable waters many years after their release […] and in highly diluted forms.”, an application that the justices find inconsistent with the CWA.

The dissenting opinion of Justice Alito rejects the introduction of the “functional equivalence” concept as too vague and inconsistent with the language of CWA.  Given the authorities of states on matters of groundwater and nonpoint source pollution, he supports the “bright-line test”.  But importantly, Justice Alito instead refers to the definition of “point source” as a means to avoid the loopholes cited in the majority opinion as reason to reject the “bright-line test”:  He points out that, according to CWA, “point source[s] include [….] ‘any discernible, confined and discrete conveyance… from which pollutants … may be discharged.’ §1362(14).” The opinion continues to describe how the pathway created by pollutant discharge from a pipe onto a beach and ending in the ocean” or many of the cases that trouble the Court” would easily be covered by applying common definitions of “conveyance”, “discernable”, and “confined”.  Groundwater hydrologists may further point out something not mentioned and perhaps not considered by Justice Alito: that we do have scientific tools (as referred to by the majority opinion) to similarly describe some groundwater pathways as a conveyance that is indeed discernable and confined, “i.e., held within bounds”.  So perhaps Justice Alito’s argument, from a scientific perspective, would in practice not be substantively different from the scientific criteria that the majority opinion associated with defining “functional equivalent” point source discharge. Such an interpretation would add further support and a consistent angle to the overall spirit of the Court’s decision.

The Maui decision is already having a ripple effect in other areas of environmental concern.  Environmentalists have long been advocating against the use of coal ash impoundments—open pits for disposal of toxic byproducts left over from burning coal.  Many of these byproducts have allegedly moved from these impoundments through groundwater into streams and rivers.  Prior to the decision in Maui, power companies argued the CWA permitting program was inapplicable to impoundments.  But the Maui decision will likely lend weight to these challenges.

The Maui decision also will likely impact litigation over the federal administration’s repeal of the Water of the United States rule, a regulation under the Obama administration which clarified the views of the Environmental Protection Agency and the U.S. Army Corps of Engineers about the reach of the Clean Water Act.  In this repeal, this administration specifically stated, in response to commenters, that “A groundwater or subsurface connection could also be confusing and difficult to implement, including in the determination of whether a subsurface connection exists and to what extent.” U.S. Army Corps of Engineers and Environmental Protection Agency, The Navigable Waters Protection Rule: Definition of ‘‘Waters of the United States,” 85 Fed. Reg. 22,250, 22,313 (Apr. 21, 2020).  Promulgated by the agencies before the Maui decision came out, the agencies will likely have to wrestle with the Maui decision in subsequent challenges.

While the decision leaves some previous uncertainty over the interpretation of the CWA, and perhaps adds some, California dischargers are unlikely to face additional regulation under this decision. Under the Porter-Cologne Water Quality Control Act, California already requires permits for discharges to groundwater, even if they don’t meet the “functional equivalent” test outlined by Justice Breyer’s majority opinion. California regulators may need to adjust their approach to reflect that some of these permits will also serve as CWA permits under the state’s authority, but this should not impose significant new burdens on regulated entities. California’s robust implementation of a strong groundwater quality regulatory program, implementing state laws (including the Sustainable Groundwater Management Act, SGMA) and other federal laws governing discharge of pollutants to groundwater (Safe Drinking Water Act, Toxic Substances Control Act, Resources Conservation and Recovery Act, state and federal Superfund programs) puts it in an excellent position to have little to worry about a new layer of bureaucracy and restrictions.

The decision’s reliance on strong groundwater science marks another significant step in the emerging integration of groundwater and surface water. The California courts and legislature have long regarded surface water and groundwater as legally distinct, but over the last decade that legal fiction has begun to break down. In 2014, SGMA explicitly recognized the relationship between groundwater and surface water, requiring groundwater managers to avoid significant and unreasonable adverse impacts on beneficial uses of surface water. In 2018, a California appellate court ruled that the public doctrine applies to groundwater extraction if it adversely impacts a navigable waterway. This decision validates the hard work of water scientists working to protect critical freshwater systems in the context of integrated watershed and water resources management, including efforts to protect many of these freshwater resources that depend on high quality groundwater discharge. And it reminds us to keep hard at working to achieve the larger vision of the Clean Water Act.

Thomas Harter is a professor of Hydrologic Sciences and a Cooperative Extension Groundwater Specialist at the University of California, Davis.  He is currently acting director of the UC Davis Center for Watershed Sciences and Chair of the Hydrologic Sciences Graduate Group

Steph Tai is a professor of law at the University of Wisconsin Law School.  Their research focuses on areas of science, risk, and environmental and food regulation.

March 16, 2020

New science or just spin: science charade in the Delta

[Cross-posted from CaliforniaWaterBlog]

By Karrigan Börk, Andrew L. Rypel and Peter Moyle

Science-based decision making is key to improved conservation management and a legal mandate in the US Endangered Species Act.  Thus supporters of federal efforts to increase water exports from the Central Valley Project (CVP) and State Water Project (SWP) have claimed that these efforts are based on new science. Yet unpacking those claims requires some legal analysis, a basic understanding of science, and more than a little nuanced reading.

First, some background. For a review of federal efforts to increase Delta exports, and the recent biological opinions (BiOps) released by the U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) approving those efforts, please see this earlier blog post. California has elected to sue the federal government over the recent BiOps, and, at the same time, California is proceeding with its own analysis of plans to change the operation of the SWP. Finally, the State Water Resources Control Board (SWRCB) is updating the state’s Bay Delta Plan, which addresses water quality and quantity in the Delta. The SWRCB has adopted a new plan for the San Joaquin River watershed, and is in the process of adopting a plan for the Sacramento River watershed. However, adoption and implementation efforts appear to be on hold while the Newsom Administration attempts to negotiate voluntary agreements with water users and environmental groups. The voluntary agreements might ultimately replace (or be integrated into) a comprehensive Bay Delta Plan update. There are many moving parts, but one thing tying all these efforts together is the proponents’ claim that their approach is mandated by the best science.

Supporters of the federal plan in particular seek to wrap the effort in the mantle of science. On the media call for the roll out of the new BiOps, Paul Souza, Regional Director for US Fish and Wildlife Service cited “tremendous new science now that we didn’t have a decade ago.” On the same call, Ernest Conant, Regional Director of the Mid-Pacific Region of the Bureau of Reclamation, argued that the new approach was “infused with new scientific information.” U.S. Rep. Kevin McCarthy, R-Bakersfield, told Fox News “this president has worked greatly using science, not based on politics but on science, to allow to have more of that water stay with the Californians and America.” Finally, during his remarks to Rural Stakeholders on California Water Accessibility in Bakersfield, CA, President Trump argued that the old plan was based on “old science, obsolete studies, and overbearing regulations that had not been updated in many, many years, and sometimes for decades,” promising that the new federal plans “use the latest science and most advanced technology.” The science drumbeat has played a central role in this media blitz.

The rationale for this approach is easy to understand. Policy makers frequently cloak political decisions in a scientific framework; in policy circles, this is known as the science charade (Adler 2017; Wagner 1995). The science charade lets political leaders avoid responsibility for unpopular decisions – they’re just following the science, not making hard decisions based on their own ethical considerations (Doremus 1997). The science charade also lets decision makers minimize public input on policy decisions – why should the uninformed public have a say in technical decisions (Adler 2017)? Scientists themselves sometimes embrace this approach because it affords them a measure of control over policy decisions (Adler 2017). The courts only reinforce the science charade – they are very reticent to overturn federal agency decisions that claim to be based on science, rather than policy preferences (Clark 2009).

This approach is not limited to supporters of the federal plans; everyone claims that science is on their side. But the current federal roll out is uniquely focused on claiming that new science justifies increased water exports from the Delta. Moreover, NMFS brought in new scientists to rewrite their draft BiOp last summer, after the first draft concluded the federal pumping plan was likely to drive species to extinction. This suggests some skepticism about NMFS’s claims to rely on “new science.”

Natural resource sciences are unique compared to many fields (e.g., physics). For example, the best natural resource science normally involves understanding not only the organisms of interest, but also the dynamics of their complicated ecosystems, which in turn are typically controlled by people. Indeed, most scientists are trained to view natural resource management quite broadly, e.g., as the intersection of organisms, habitat and people (Nielson 1999). Each aspect is critical and affects the other two, and managing with all three in mind presents opportunities for enhancing natural resources overall. However, management frequently goes awry when a disproportionate focus is placed on only one aspect of the problem (Sass et al. 2017). The science charade preys on the misconception that these spheres should be disconnected, suggesting we can somehow separate organisms and ecosystems from the decisions people make.

The US Endangered Species Act explicitly requires that federal decisions consider the best available science. For example, 16 U.S. Code § 1536(a)(2) requires that “each agency shall use the best scientific and commercial data available” when preparing biological opinions under the Act.  This is, objectively, the right approach. Bad science leads to bad decisions. But this mandate also encourages the cloaking of policy preferences as scientific mandates (Adler 2017). Consider three aspects of the current political struggle over Delta water.

First, the roll out for the new biological opinions treats existing science as old and obsolete, claiming it is no longer the best available science. But science is not milk. It doesn’t just go bad. New science can illuminate, and the state of the art sometimes changes over time, but older science is not inherently wrong or less valuable. Science grows by building on existing ideas and knowledge, not by rejecting it outright. As Isaac Newton famously wrote, “If I have seen a little further, it is by standing on the shoulders of giants.” For example, the 2010 report “Development of Flow Criteria for the Sacramento-San Joaquin Delta Ecosystem” found that flow standards aimed solely at protecting fish populations in the Delta would require 75% of the unimpaired flow in the Sacramento and San Joaquin watersheds. Certainly, other water needs mean that the Delta will not get these flows, but simply dismissing this report as old science is inherently flawed.

Second, to the extent that new science requires new approaches in the Delta, existing new science indicates that restoration of the Delta will require more water to be left in the Delta, not less. The 2017 Scientific Basis Report for the SWRCB Bay Delta Plan effort noted that additional flows into the Delta, and decreased exports of water from the Delta, always benefits native biota, provided that temperature, timing, and quality targets were met. Zero new science shows that native fishes and most other native organisms in the Delta can survive on less water.  Keep in mind that the Delta is one of the best studied estuarine ecosystems in the world, with continuous major research producing new and improved understanding of the ecosystem (i.e. science).

Third and finally, the new science claims in the biological opinions seem to focus on emerging approaches that might reconcile water use with ecosystem needs based on real time monitoring and habitat improvements. But immediate claims that this new science allows greater water exports from the Delta hides key policy decisions on acceptable extinction risks.

For example, the real time “Enhanced Delta Smelt Monitoring (EDSM)” program is supposed to allow managers to reduce pumping from the Delta when monitoring detects smelt in the area around the pumps, thus keeping smelt from being sucked into the pumps. But smelt populations are currently too low to detect, and a January 2018 independent scientific review concluded, “it is difficult to see how the EDSM currently can be used to inform water operations in near real time.” The review encouraged FWS to attempt to validate this approach, but the BiOps offer no such validation. Using this approach without showing that it works places all risk of failure on the Delta Smelt, and ultimately risks their extinction. This is a policy decision, not new science standing alone.

Similarly, the BiOps indicate habitat improvements will reduce the need for water in the Delta. As prior blog posts here have noted, better habitat improves salmon growth, which may improve salmon survivorship. Better habitat also may allow managers to reconcile human uses of the landscape with ecosystem needs. Could this approach allow managers to achieve ecosystem and species recovery targets with less water? It seems unlikely, but the BiOps depend on habitat improvement to make up for increased water exports. Even if this approach could work, it would require that suitable habitat improvements be in place before water exports increase. But most improvements mandated in the last round of BiOps are merely proposed, not complete, and most ongoing improvement projects remain unfinished and untested.

The increased pumping anticipated in the BiOps would begin well before any improvements in species numbers would result from habitat improvement. This approach assumes that additional unspecified habitat will compensate for decreased water in the short term. Success would depend entirely on protected species being lucky enough to persist under current conditions but with less water. Suggesting that the decisions expressed in the BiOps are based solely on science masks this central policy calculus, which is never explicitly revealed. However, the benefits of such an approach to Delta water users are well-documented: there is less political accountability, less public input, and more deferential court review.

What’s the solution? There’s no magic bullet to stop the science charade, but using properly vetted (i.e., peer-reviewed) science literature and independent science reviews of new rulemakings can go a long way toward ensuring true science-based policies. California’s Delta Science Program, for example, relies on an independent review panel to provide objective feedback to policymakers. Adaptive management approaches that would increase ecosystem protections if new approaches fail would better allocate risk in uncertain situations. The science community itself must also watch and safeguard how policy makers use its work. It is not enough to simply conduct and publish scientific articles – not anymore. And courts asked to review decisions that touch on science must distinguish between scientific conclusions and policy decisions that are cloaked as science.

In the near term, California agencies may soon face this challenge head on. First, as noted above, the California Department of Water Resources (DWR) is preparing an environmental analysis of its own plans to change the operation of the Delta pumps. DWR has proposed a plan that embraces some of the same approaches to science used by the federal plan. Comments from the California Department of Fish and Wildlife (CDFW) and the SWRCB to DWR have raised these concerns, but it is not yet clear how the DWR will respond and whether CDFW will ultimately grant DWR the permits it needs to proceed on the terms DWR has proposed.

Second, the SWRCB will have to approve any voluntary agreements that are developed for the Delta. The Newsom Administration is pushing hard for a suite of voluntary agreements to benefit the Delta ecosystem while also meeting water user needs. The benefits of successful voluntary agreements are tantalizing: an infusion of private funding, improved habitat, improved ecosystems, and continued availability of needed water, all done faster and with fewer lawsuits. But any agreements must ultimately comply with state environmental law, and the SWRCB will make the first determination as to whether the science supports whatever voluntary agreements the Administration can develop. The voluntary agreements appear to rely on the same habitat-for-water hopes that undergird the BiOps, and the agreements would lock in the water withdrawals before regulators know if the habitat improvements actually work. A safer approach would be to improve the habitat, and then conduct scientific studies to see if listed species actually benefit before withdrawing additional water. Failing that, the agreements should at least provide for water use reductions as a fail safe if species declines continue despite the new habitats. The best available science recognizes that nature is sometimes unpredictable and science is sometimes misread or just wrong. It requires contingency plans.

If the Administration succeeds in developing a set of voluntary agreements, and as DWR concludes its environmental analysis, look for the media blitz to emphasize that science supports their approach. It will fall to the state regulatory agencies to determine whether they are truly supported by science, or merely by a science charade. 

Further Reading

Jonathan H. Adler, The Science Charade in Species Conservation, 24 Sup. Ct. Econ. Rev. 109, 116 (2017).

Sara. A. Clark, Taking a Hard Look at Agency Science: Can the Courts Ever Succeed?, 36 Ecol.L.Q., 317 (2009).

Holly Doremus, Listing Decisions Under the Endangered Species Act: Why Better Science Isn’t Always Better Policy, 75 Wash. U. L.Q. 1029, 1038 (1997)

Carson Jeffres, Frolicking fat floodplain fish feeding furiouslyJune 2, 2011.

Peter Moyle, Jeff Opperman, Amber Manfree, Eric Larson, and Joan Florshiem, Floodplains in California’s Future, Sept. 10, 2017.

Peter Moyle, Karrigan Börk, John Durand, Tien-Chieh Hung, and Andrew Rypel, Futures for Delta Smelt, Dec. 15, 2019.

Larry A. Nielsen, History of Inland Fisheries Management in North America in Inland Fisheries Management, 2nd Ed. 3 (Christopher C. Kohler and Wayne A. Hubert eds., 1999).

Greg G. Sass, Andrew L. Rypel, and Joshua D. Stafford, Inland Fisheries Habitat Management: Lessons Learned from Wildlife Ecology and a Proposal For Change, 42 Fisheries 197 (2017).

Wendy Wagner, The Science Charade in Toxic Risk Regulation, 95 Colum. L. Rev. 1613 (1995).

 

December 20, 2019

Futures for Delta Smelt

[Cross-posted from California WaterBlog]

By Karrigan Bork

Co-authored with Peter Moyle, John Durand, Tien-Chieh Hung and Andrew Rypel

A recent biological opinion (BiOp) released by the U.S. Fish and Wildlife Service (FWS) concluded that a proposed  re-operation of California’s largest water projects will avoid driving the federally threatened Delta smelt to extinction. The plan proposes increasing water exports from the Central Valley Project and State Water Project, which will reduce water available for ecosystems and local uses. Both projects move water through pumps in the California Delta, a productive but sensitive ecosystem and home to the Delta smelt.

Under the federal Endangered Species Act (ESA), the FWS reviews federal agency actions to ensure that they will not drive listed species into extinction. In 2009, FWS reviewed the operation of the state and federal pumps that export water from the Delta and concluded in a BiOp that operation of the massive pumps jeopardizes the smelt’s continued existence. FWS required reduced pumping and other measures to protect the smelt, and those measure are currently in effect.

In 2019, the FWS again reviewed this new plan for the pump operations and concluded that many of the 2009 protections were actually not necessary and that the pumps could export significantly more water without jeopardizing the smelt. It draws this conclusion in two ways. First, the opinion notes that “recent abundance trends strongly suggest [the smelt] is in the midst of demographic collapse” and will likely go extinct without intervention. Based on this existing trajectory, the opinion concludes it won’t be the project’s fault when smelt disappear. Second, the opinion implies that, because agencies will spend $1.5 billion on habitat restoration, a production hatchery for smelt, and other measures, the net effect for the smelt will be positive. Based on these considerations, FWS concluded that the new operation plan would not drive the smelt to extinction, although it acknowledges extinction might happen anyway.

But the BiOp considers a very narrow question. The BiOp does not consider whether the plan is likely to improve the smelt’s status, and this BiOp in particular constrains its analysis so it does not meaningfully consider what is likely to happen to the Delta smelt under the new plans.

So, moving away from the narrow BiOp and considering the smelt in a broader context, what is going to happen to smelt in the wild? Is extinction likely?  This essay explores some issues affecting Delta smelt and suggests possible futures. This blog is a short version of a longer white paper (with references) available at: https://watershed.ucdavis.edu/shed/lund/papers/FuturesForDeltaSmeltDecember2019.pdf.

The basic problem

The estuary where Delta smelt evolved no longer exists, and smelt are poorly adapted for the new conditions. Much of the water that once flowed through the estuary is stored or diverted upstream or exported by the south Delta pumps (Hobbs et al. 2017; Moyle et al. 2016, 2018). The smelt’s historical marsh habitats are now artificial channels and levees protecting agricultural islands. These hydrologic and physical changes make the Delta prone to invasion by non-native organisms, some of which disrupt food webs and confound restoration. Lower flows allow salts, toxic chemicals, and nutrients to accumulate. Harmful algae blooms occur regularly. As climate change further disrupts flows and increases temperatures, little historical habitat is left for sensitive species like smelt.

A tipping point

Smelt populations have probably been in gradual decline since at least the 1950s (Figure 1), but their population has collapsed since the 1980s, tracking the increase in water exports (Figure 2). This correlation is compelling, but other major system changes took place in the same period.  In the late 1980s, an invasive clam spread through the Delta, removing much of the smelt’s planktonic food supply. Concurrently, invasive weeds spread across the Delta, transforming former Delta smelt habitats into clear, food limited, lake-like environments. From 1969-89, the Delta tipped away from good smelt habitat to a novel ecosystem unfavorable to smelt.  This shift is practically irreversible, and the shift put the Delta smelt on a trajectory toward extinction as a wild fish. It is currently largely absent from surveys that once tracked its abundance.

Figure 1. Indices of Delta Smelt abundance in the Delta’s two longest-running fish sampling programs, the Summer Townet Survey (for juvenile smelt) and the Fall Midwater Trawl Survey (mostly pre-spawning subadults). Figure by Dylan Stompe.

 

Figure 2. Annual water export (left axis) from the south Delta by the State Water Project (red) and federal Central Valley Project (blue) in million acre-feet. Gray bars show droughts, when pumping was reduced primarily because of low inflows. Annual inflows of water to the Delta in million acre-feet (right axis) are open circles. Data: www.water.ca.gov/dayflow. Figure: Moyle et al. 2018 https://afspubs.onlinelibrary.wiley.com/doi/full/10.1002/fsh.10014

Is habitat restoration the answer?

The BiOp relies in part on habitat restoration under California’s EcoRestore and other programs to support flagging smelt populations. There is little guarantee that this will make much difference to smelt, although many other native species will benefit.

First, the area under restoration is insufficient. Delta smelt originally inhabited an area about the size of Rhode Island, moving opportunistically to find appropriate conditions. Because Delta smelt are migratory and pelagic, smelt will overlap with restoration sites only occasionally. Successful habitat restoration would have to include multiple sites adjacent to water corridors, with abundant food and cool water, and in areas suitable for both spawning and rearing. Instead, the restoration approach has been more opportunistic than strategic, with restoration often focused on wetlands with willing sellers, regardless of suitability. We have little working knowledge whether we can build, connect, and manage these sites to benefit smelt.

Second, some projects rely on the idea that just creating tidal wetlands will be sufficient. It will not. Most Delta restoration sites are vulnerable to invasion by non-native species, which can subvert habitat solutions. Successful restoration sites require intensive, continuous management to meet even minimum expectations of restored habitat, and there is little incentive to actively manage “natural” restoration sites.

Third, current smelt populations are too small to be able to see an immediate (annual) response to habitat changes alone. Whatever steps are taken to protect smelt may be too little too late.

Finally, while water users hope that restoration provides an alternative to water use, this is not realistic. Successful restoration requires water flowing across the landscape. Moving water promotes the exchange of nutrients, controls introduced species, distributes food production, and creates habitat structure. Flows help restorations mimic natural environments and improves their effectiveness. Flows give managers better control of where Delta smelt end up during the spring, summer and fall. Habitat with minimal outflow is an empty promise.

If we are serious about providing the outflow required for habitat for smelt and other fishes, a substantial environmental water right is needed to provide reliable water to interact with physical habitat to produce food and shelter. Allocation of a sufficient water right is difficult to envision, given the current conflicts in the Delta, but California’s Bay Delta Plan, currently under development, generally proposes significant water for Delta fish, based on a percentage of the rivers’ natural flows. If this water were treated as a right under the control of an ecosystem manager, Delta smelt might have a chance of more than extinction avoidance—they might recover.

Hatchery Smelt

The BiOp also relies on hatchery supplementation of wild stocks to mitigate smelt impacts. The UC Davis Fish Conservation and Culture Laboratory (FCCL) has maintained a genetically managed Delta smelt population since 2008, but low wild smelt numbers complicate its operation. FWS allows FCCL to incorporate 100 wild Delta smelt into its population annually, to maintain genetic diversity, but recently the FCCL has been unable to capture 100 individuals. Without those fish, inbreeding might rapidly increase and add further uncertainty to the success of supplementation.  Other hatchery supplementation programs, such as those for salmon, have had limited success in re-establishing self-sustaining wild populations. The smelt efforts will likely follow suit (Lessard et al. 2018).

Conclusions

Based on our experience and research in the Delta, any benefits from the habitat restoration and hatchery plans in the new opinion are too uncertain to reliably offset negative impacts of increased water exports. The Delta has changed so much that suitable habitat for Delta smelt is increasingly lacking. Large-scale restoration projects that provide habitat and food for smelt will at times need increased outflows.  Desperate measures such as a production smelt hatchery and establishment of smelt in reservoirs may provide a veneer of ‘saving’ smelt for a while, but they seem unlikely to prevent extinction in the long run. In short, the smelt are likely to continue on their extinction trajectory. The following seem the most likely alternative futures for Delta smelt, in rough order of likelihood:

  1. Extinction of the wild population in 1-5 years, with a population of increasingly domesticated hatchery smelt kept for display and research purposes.
  2. Persistence of a small wild population in a few limited intensively managed habitats, until these habitats cease being livable from global warming and other changes.
  3. Global extinction after wild populations disappear and hatchery supplementation or replacement fails.
  4. Replacement of the wild population with one of hatchery origin, continuously supplemented.
  5. Persistence of wild populations as the result of supplementation and through establishment of reservoir populations.

The authors are at the University of California – Davis, Center for Watershed Sciences.

Further reading

Hobbs, J.A, P.B. Moyle, N. Fangue and R. E. Connon. 2017. Is extinction inevitable for Delta Smelt and Longfin Smelt? An opinion and recommendations for recovery.  San Francisco Estuary and Watershed Science 15 (2):  San Francisco Estuary and Watershed Science 15(2). jmie_sfews_35759. Retrieved from: http://escholarship.org/uc/item/2k06n13x

Lessard J., B. Cavallo, P. Anders, T. Sommer, B. Schreier, D. Gille, A. Schreier, A. Finger, T.-C. Hung, J. Hobbs, B. May, A. Schultz, O. Burgess and R. Clarke (2018) Considerations for the use of captive-reared delta smelt for species recovery and research, San Francisco Estuary and Watershed Science 16(3), article 3.

Moyle, P. B., L. R. Brown, J.R. Durand, and J.A. Hobbs. 2016. Delta Smelt: life history and decline of a once-abundant species in the San Francisco Estuary. San Francisco Estuary and Watershed Science14(2) http://escholarship.org/uc/item/09k9f76s

Moyle, P.B., J. A. Hobbs, and J. R. Durand. 2018.  Delta smelt and the politics of water in California. Fisheries 43:42-51.

Moyle, P.B., K. Bork, J. Durand, T-C Hung, and A. Rypel. 2019. “Futures for Delta Smelt”. Center for Watershed Sciences white paper, University of California – Davis, 15 December, https://watershed.ucdavis.edu/shed/lund/papers/FuturesForDeltaSmeltDecember2019.pdf