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Ephemeral , such as this one in western South Dakota, have lost federal protection INSIGHTS under the NWPR

POLICY FORUM

WATER Distorting science, putting water at risk A recent rule is inconsistent with science and will compromise the integrity of U.S. waters

By S. Mažeika Patricio Sullivan1, Mark C. ing water quality and healthy watersheds in water protections, which went into effect Rains2, Amanda D. Rodewald3,4, William W. (3) (see the figure). Although the Agencies nationwide on 22 June, will require coordi- Buzbee5, Amy D. Rosemond6 claim to have “looked to scientific princi- nated efforts among scientists, lawmakers, ples to inform” the NWPR, science has been and resource managers. he Navigable Waters Protection Rule largely ignored and oversimplified. These Clearly articulated in the CWA is the in- (NWPR) (1), which was published new exclusions are based on selective pars- tention “to restore and maintain the chemi- in April by the U.S. Environmental ing of statutory language and earlier case cal, physical, and biological integrity of the Protection Agency (EPA) and the law, rather than on previously established, Nation’s waters” (4). The CWA was explicit Department of the Army (“the science-based interpretations of the U.S. in protecting “navigable waters,” which Agencies”), has redefined “waters of Federal Water Pollution Control Act, com- Congress defined broadly as WOTUS; how- Tthe U.S.” (WOTUS) to restrict federal pro- monly known as the Clean Water Act (CWA) ever, the extent to which waters other than tection of vulnerable waters (2). With its (4). The EPA’s own Science Advisory Board navigable rivers, lakes, and territorial seas emphasis on “continuous surface connec- (SAB) found sufficient evidence to conclude [traditional navigable waters (TNWs)] are tions” and “permanen[ce],” the NWPR re- that “…the proposed Rule lacks a scientific protected has repeatedly provoked legal moves or reduces protection for U.S. waters, justification, while potentially introduc- skirmishing. Particularly contentious are including millions of miles of streams and ing new risks to human and environmen- determinations about which nontraditional acres of , many of which comprise tal health” (5). Responding to this unprec- waters, such as wetlands and small

headwaters that are critical for sustain- edented distortion of science and rollback streams, contribute to the integrity of TNWs. SULLIVAN P. M. S. PHOTO:

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The NWPR functionally ends the debate by derstanding recognizes as critical to services Because these wetlands and streams will elevating state over federal regulatory author- derived from freshwater ecosystems gradi- summarily lose federal protection, they will ity. Without federal law as a protective regu- ents of connectivity (versus a binary prop- be vulnerable to outright destruction, fill, or latory floor, states can and often do choose erty: connected, not connected) that oper- unpermitted industrial pollution discharges to leave waterbodies unprotected, making ate as a function of frequency, magnitude, that risk transporting pollutants throughout waters vulnerable to unregulated pollution, timing, and duration of biological, chemical, watersheds. Losses of nonfloodplain wet- dredging, filling, and other activities that and physical connections among waterbod- lands could include particularly vulnerable may profoundly erode water quality (3). ies (10). By disregarding or misinterpreting and often valuable waters (2), including The NWPR downplays science by redefin- the science of waterbody connectivity, the some playa lakes, prairie potholes, Carolina ing protected “waters” and explicitly states NWPR draws scientifically unsupported and Delmarva Bays, pocosins, and vernal that “science cannot dictate where to draw boundaries to distinguish WOTUS, reaches pools. A preliminary analysis predicts wide- the line between Federal and State waters.” conclusions contrary to current science, and spread losses of functions, with The NWPR relies overwhelmingly (and ar- asserts legal and scientific views substan- particularly high impacts on wetlands in guably arbitrarily) upon the 2006 Supreme tially different from those of the Agencies arid and semi-arid regions. For example, Court opinion by Justice Scalia in Rapanos under previous administrations of both po- the CWR protected 72%, whereas the NWPR v. United States, Carabell v. United States litical parties going back to the 1970s. The will only protect 28% of wetland acres, in Army Corps of Engineers that lacked major- NWPR promotes regulations contrary to New Mexico’s Río Peñasco watershed (11). ity support. A more scientifically nuanced what science shows about effective water The NWPR also categorically excludes position was articulated by Justice Kennedy protection. Although agencies often have subsurface hydrologic connectivity. To dis- on the same case; the four dissenting latitude to adjust regulatory choices when regard groundwater connectivity is to dis- Justices agreed with Kennedy’s rationales implementing longstanding statutes, they regard the scientific understanding of how for protecting waters, but would have pro- cannot do so arbitrarily and without rea- natural waters function. The Agencies justify tected even more. soned justification and rationales in light of this exclusion by claiming that “A ground- The realized impacts are likely to be relevant law, facts, and science. water or subsurface connection could also worse than projected, as ephemeral streams In contrast to the CWR’s recognition of be confusing and difficult to implement.” and nonfloodplain wetlands are usually biological, chemical, and physical connectiv- Although implementation may be challeng- underestimated by remotely sensed data ity, the NWPR relies solely on direct hydro- ing in some cases, claimed implementation (3). The economic analysis filed with the logic surface connectivity to determine wet- ease under the NWPR should not supersede NWPR was largely silent about impacts, land jurisdiction. Nonfloodplain wetlands an evidence-based determination of connec- simply acknowledging that “the [A]gencies and ephemeral streams are categorically tivity given the potential for economic and are unable to quantify [the scope] of these excluded on the basis of lack of hydrologi- environmental harm. changes with any reliable accuracy” owing cal connectivity irrespective of their degree to geospatial data issues and uncertainty of biological or chemical connectivity. Also A PATH FORWARD IN UNCERTAIN TIMES about government responses (6). Yet, in excluded are wetlands lacking a The NWPR directly conflicts with a growing spite of this uncertainty and the potential direct surface water connection to TNWs “in body of scientific evidence and with input for harm, the Agencies proceeded with a re- a typical year,” and intermittent and review by federal and nonfederal scien- strictive and risky rule. lacking relatively permanent surface flows. tists. The rule narrows WOTUS in ways that Such exclusions are inconsistent with evi- are inconsistent with longstanding views CONNECTIVITY AND QUALITY dence demonstrating that these waters are about the CWA’s mandate to safeguard Connectivity is a cornerstone in under- functionally connected to and support the access to clean water. The NWPR opens standing how freshwater ecosystem func- integrity of downstream waters. Removal previously protected waters to filling, im- tions are sustained. In 2015, the Obama of federal protection is likely to diminish pairment, and industrial pollution, and will administration promulgated the Clean Wa- numerous ecosystem services, such as safe- undermine decades of investments restoring ter Rule (CWR) that included all tributaries guarding water quality and quantity, re- water quality across the United States and and most wetlands as WOTUS (7). The sci- ducing or mitigating flood risk, conserving lead to profound loss or impairment of eco- entific rationale for the CWR was reviewed biodiversity, and maintaining recreationally systems and the services they provide. For in the EPA Connectivity Report (8), which and commercially valuable fisheries (3). context, the economic value of ecosystem synthesized >1200 peer-reviewed scientific services provisioned by nonfloodplain wet- publications and input from 49 technical EPHEMERAL, ISOLATED lands alone has been estimated at $673 bil- experts. After a public review process, the Just as tiny capillaries play critical roles lion per year (2). 25-member EPA SAB confirmed the scien- in the human body, nonfloodplain wet- Congress has the power to strengthen the tific underpinnings of both the Connectivity lands (so-called “isolated”) and ephemeral CWA by enacting new legislation to replace Report and the CWR. streams (that flow only after precipitation or repeal the NWPR. Future administrations Since then, the body of supporting evi- events) support an extensive suite of eco- can reassess and act to restore protections dence has grown (3, 9), enhancing our un- system services. Because nonfloodplain through new rulemaking, without the need derstanding of how the integrity of freshwa- wetlands and ephemeral streams are con- for new legislation. Toward these ends, the ter ecosystems within a watershed relates to nected to one another and downstream wa- scientific community has already spoken the biological, chemical, and hydrological ters along a gradient of connectivity, they on the matter, proposing three frameworks connectivity among waterbodies, including also provide substantial cumulative or ag- for the development of renewed protections wetlands and ephemeral streams. This un- gregate ecosystem services (10). based on sound scientific merits (2).

1Schiermeier Olentangy River Wetland Research Park, School of Environment and Natural Resources, The Ohio State University, Columbus, OH, USA. 2School of Geosciences, University of South Florida, Tampa, FL, USA. 3Cornell Lab of Ornithology, Cornell University, Ithaca, NY, USA. 4Department of Natural Resources, Cornell University, Ithaca, NY, USA. 5Georgetown University Law Center, Georgetown University, Washington, DC, USA. 6Odum School of Ecology, University of Georgia, Athens, GA, USA. Email: [email protected]

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Meanwhile, litigation may present chal- Research-based evidence on the impacts exploitation of water resources. Although lenges to and perhaps enjoin implementa- of climate change were notably absent in the federal statutes grant latitude to state, tribal, tion of the NWPR. The April 2020 County NWPR and will also be critical in challeng- and local governments to provide additional, of Maui v. Hawaii Wildlife Fund may help. ing the rule. Under current human-use and more protective regulation, many states do In that case, the U.S. Supreme Court rejected water-management schemes, many not do so, and many even prohibit regula- an argument that would have eliminated flows are declining, such that intermittent tions more stringent than federally required federal CWA protections. The Court instead and perennial streams are increasingly be- (2, 14). Thus, absent federal protections, called for a functional and context-sensitive ing replaced with ephemeral streams that many waterbodies will go unprotected. analysis of the disputed activities and their will lose protection. For example, the Upper If the NWPR remains in place, local and effects to determine federal jurisdiction over Kansas River Basin lost 558 km (21%) of grassroots approaches to water conserva- intentional pollution discharges into ground- stream length between 1950 and 1980, pre- tion, including watershed councils and coali- water that predictably flows into WOTUS. In sumably as a result of groundwater pumping tions, information and educational plans to that 6 to 3 decision, the Court laid out a clear exacerbated by climate change, with a cu- reduce pollution, and university extension scientific basis for closing a loophole in the mulative loss of 844 km (32%) predicted by programs, will need to further mobilize to fill CWA, affirming for the first time that pollut- 2060 (12). Reduced mountain snowpack and the vacuum created by the new rule. Such ef- ants that travel through groundwater and increased evaporation have been implicated forts would require additional resources and heightened stakeholder coordination. j

REFERENCES AND NOTES ProtectedProtected versus unprotected waters 1. U.S. Environmental Protection Agency and Department UnderUnder thethe NavigableNavigable WatersWaters ProtectionProtection Rule,Rule, multiplemultiple waterbodywaterbody typestypes werewere underunder considerationconsideration forfor protectionprotection of Defense, Department of the Army, Corps of Engineers, asas “waters“waters ofof thethe UnitedUnited States.”EphemeralStates”. Ephemeral streams streams flow ow only only after after precipitation precipitation events, events, intermittent intermittent streams streams The Navigable Waters Protection Rule: Definition of ow periodically or seasonally, and perennial streams ow continuously. There are many types of “Waters of the United States,” 85 Fed. Reg. 22250 flow periodically or seasonally, and perennial streams flow continuously. There are many types of nonfloodplain, (A2020). ornon oodplain, “isolated” wetlands, or “isolated” including wetlands, prairie including potholes prairie and vernal potholes pools, and as vernal illustrated pools, here. as illustrated here. 2. I. F. Creed et al., Nat. Geosci. 10, 809 (2017). 3. S. A R. Colvin et al., Fisheries (Bethesda, MD) 44, 73 (2019). 4. Federal Water Pollution Control Act, 33 U.S.C. 1251 et seq., Sec. 101, p. 3 (1972). 5. U.S. EPA, Letter to Andrew Wheeler, 27 February 2020, Protected Unprotected SAB commentary on the proposed rule defining the scope of waters federally regulated under the Clean Water Perennial streams Prairie potholes Nonoodplain Act, EPA-SAB-20-002 (Environmental Protection Agency, Vernal wetlands 2020). pools (“isolated”) 6. U.S. Environmental Protection Agency and Department (individual and of the Army, Economic analysis for the Navigable Waters Intermittent aggregate) Protection Rule: Definition of “Waters of the United streams States” (EPA, 2020). (with relatively 7. U.S. Environmental Protection Agency and Department permanent Intermittent of Defense, Department of the Army, Corps of Engineers, Clean Water Rule: Definition of “Waters of the United surface ows) streams (lacking relatively States” 80 Fed. Reg. 37054 (EPA, 2015). 8. U.S. Environmental Protection Agency, Connectivity of permanent streams and wetlands to downstream waters: a review surface ows) and synthesis of the scientific evidence technical report, Floodplain wetlands EPA/600/R-14/475F (EPA, 2015). 9. S. M. P. Sullivan, M. C. Rains, A. D. Rodewald, Proc. Natl. (abutting TNWs through Ephemeral surface hydrologic Acad. Sci. U.S.A. 116, 11558 (2019). streams 10. U.S. Environmental Protection Agency, Letter to Gina connection (individual and McCarthy, 17 October 2014. SAB review of the draft EPA “in a typical year”) aggregate) report Connectivity of streams and wetlands to down- stream waters: A review and synthesis of the scientific evidence (EPA, 2014). Floodplain wetlands 11. R. Meyer, A. Robertson, Navigable Waters Protection Rule Traditional (not abutting TNWs spatial analysis: A GIS based scenario model for compara- navigable through surface tive analysis of the potential spatial extent of jurisdictional hydrologic connection and non-jurisdictional waters and wetlands (Saint Mary’s waters (TNWs) University of Minnesota, Winona, MN, 2020). “in a typical year”) 12. J. S. Perkin et al., Proc. Natl. Acad. Sci. U.S.A. 114, 7373 (2017). Groundwater 13. P. C. D. Milly, K. A. Dunne, Science 367, 1252 (2020). 14. State constraints: State-imposed limitations on the authority of agencies to regulate waters beyond the then emerge into surface waters are in fact in the ~20% decline in the Colorado River’s scope of the federal Clean Water Act (Environmental Law covered by the CWA. mean annual flow in comparison to the pre- Institute, 2013). Redoubled research efforts also can help vious century; the Upper Colorado River ACKNOWLEDGMENTS address knowledge gaps critical for effec- basin supplies water to around 40 million We thank the many individuals who contributed to previous tive water policy. Quantifying the potential people and supports ~16 million jobs (13). and related documents concerning the proposed replace- ment rule that helped inform this paper, including letters to “harm” to clean water that will be caused Adoption of the NWPR is an indicator that the Federal Register (Docket ID No. EPAHQ-OW-2018-0149) by the NWPR is critical for both litigation the federal government is at least in part and Public Input on the SAB Commentary on the Proposed and future rulemaking. Thus, the scientific shedding the use of science and responsibility Rule Defining the Scope of Waters Federally Regulated under community will be challenged to further for water protection. Additional federal roll- the Clean Water Act (84 FR 4154). We also thank L. Poff, W. Kleindl, and three anonymous reviewers for their critiques demonstrate the consequences of changes backs of environmental protection, such as and suggestions in earlier drafts. R. B. Keast and S.M.P.S. to physical, chemical, and biological con- the Update to the Regulations Implementing developed the figure. S.M.P.S. is currently providing advisory nectivity on water quality—especially in the the Procedural Provisions of the National and expert consulting services to ongoing litigation regarding the NWPR. context of nonperennial streams and non- Environmental Policy Act, a rule finalized

floodplain wetlands. on 15 July, could create a perfect storm for 10.1126/science.abb6899 SCIENCE BAUM/ THOMAS MELISSA GRAPHIC:

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