Litigation Tracking

Legal advocacy is a central component of NACWA’s mission to advance national clean water advocacy goals on behalf of NACWA Member Agencies. NACWA participates in litigation nationwide to protect the legal rights of Association members, ensure the national perspective of the municipal clean water community is aggressively represented, and advocate for the establishment of sound legal precedent in clean water matters.

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NACWA litigates in both federal and state courts in a variety of roles, including as a petitioner, intervenor, and amicus curiae. Please click on the names of the cases below to get more detailed information and analysis on the litigation and NACWA’s participation, as well as access relevant court filings.

Refer to the Clean Water Acronym/Abbreviation List for abbreviations that are commonly used in clean water litigation.

Please contact NACWA’s General Counsel, Amanda Aspatore, with any questions about NACWA’s legal advocacy.

Active Cases

Last Updated: March 2026

PFAS

Farmer (PEER) v. EPA – Plaintiffs allege that EPA failed to perform a nondiscretionary duty under the Clean Water Act (CWA) to identify and regulate certain PFAS found in biosolids. NACWA intervened to ensure the voice of the clean water community would be represented in this critical lawsuit. In September 2025 the US District Court for the District of Columbia granted NACWA and DOJ’s joint motions to dismiss the case, holding that the CWA does not set a specific timeline for EPA to identify or regulate pollutants in biosolids. In December 2025 Plaintiffs appealed the case to the US Court of Appeals for DC Circuit.
NJDEP v. DuPont and 3M – As a result of litigation brought by the New Jersey Department of Environmental Protection (NJDEP) against major chemical manufacturers over PFAS contamination throughout the state, NJDEP, 3M and DuPont proposed to enter into settlement agreements purporting to bind clean water utilities and other entities within the state.

Chamber of Commerce v. EPA – Challenge brought by the U.S. Chamber of Commerce seeking to overturn the U.S. Environmental Protection Agency’s (EPA) 2024 designation of two PFAS chemicals - PFOS and PFOA - as hazardous substances under the Comprehensive Environmental Review, Compensation, and Liability Act (CERCLA) section §102.

Completed Cases

San Francisco v. EPA

Challenge to inclusion of generic “backstop” language in utility NPDES permits requiring that discharges not “cause or contribute” to the violation of applicable water quality standards.

Air Quality/Climate Change Issues

Center for Biological Diversity, et al., v. EPA (Challenge to EPA’s deferral of CO2 emissions from biogenic sources, including POTWs, from federal greenhouse gas regulations)

Biosolids

Gilbert v. Synagro (case addressing whether land application of biosolids is an agricultural activity protected under Pennsylvania’s right to farm act)
County of Kern, CA v. City of Los Angeles (Appeal of a local ordinance banning the land application of biosolids)
NACWA v. EPA (Challenge to EPA’s final Sewage Sludge Incinerator (SSI) Rule setting new air emissions standards for SSI units)
State of Washington v. Wahkiakum County (Appeal of a local ordinance banning the land application of biosolids)

Clean Water Act/Safe Drinking Water Act Nexus

Greenway Foundation v. Wolk (Challenge to Colorado decision requiring use of orthophosphate for corrosion control in drinking water system)

Consent Decrees

United States and the State of Illinois v. Metropolitan Water Reclamation District of Greater Chicago (Appeal by environmental activist groups to federal court approval of wet weather consent decree successfully negotiated by MWRD with federal and state regulators in late 2011)

Constitutional Issues

Sheetz v. County of El Dorado - Plaintiff claimed that an impact fee imposed on him by El Dorado County violated the Fifth Amendment “Takings” Clause. The trial court and court of appeals ruled that the fee imposed was not unconstitutional. NACWA become involved when Plaintiff sought review from the Supreme Court as any Supreme Court ruling on how the Fifth Amendment’s "takings" clause applies could significantly affect clean water and drinking water utilities’ ability to collect development‑related fees, including impact fees. The Supreme Court vacated saying that impact fees are subject to Nollan /Dolan standard and remanded to lower court to apply the Nollan/Dolan standard.
- Supreme Court Issues Narrow Ruling on Municipal Impact Fees, Punting on Bigger Questions
- NACWA, AMWA Partner to Take Defense of Utility Fees to U.S. Supreme Court
Anderson Creek Partners, et. al. v. Harnett Co. – Challenge brought by developers in North Carolina Supreme Court claiming that routine water and sewer impact fees are “takings” subject to the requirements of the Fifth Amendment of the U.S. Constitution.
- North Carolina Supreme Court Holds Municipal Sewer Impact Fees Subject to Constitutional "Takings" Analysis
  - North Carolina Supreme Court Takings Decision
- NACWA Files Amicus Brief Defending Wastewater Impact Fees From Constitutional Challenges
  - NACWA Amicus in Support of Harnett County

West Virginia v. EPA – Challenge that EPA’s Clean Power Plan (CPP) went beyond EPA’s authority provided by Clean Air Act (CAA) Section 111(d) by mandating fuel switching at existing power plants as part of EPA’s regulation of greenhouse gasses. NACWA became involved not to weigh in on the proper scope of Section 111(d), but rather because several parties challenging the CPP were asking the Supreme Court to issue a decision based on broad constitutional principles – specifically, “nondelegation” and “major questions” – which could have had impacts on EPA’s ability to regulate greenhouse gasses at all under the CAA, as well as on EPA’s implementation of other federal statutes including the Clean Water Act.

County of Maui v. Hawaii Wildlife Fund - Case involving whether the Clean Water Act requires a permit when pollutants are discharged from a point source into groundwater that then flows into navigable waters. The U.S. Supreme Court held that a permit is required when such a discharge is the “functional equivalent of a direct discharge” to navigable waters.

Supreme Court Outlines New Test for Determining When Clean Water Act Permits Are Required
- Supreme Court County of Maui Decision

CSO LTCP Permitting

Columbus Water Works v. Dunn – Challenge to Georgia Environmental Protection Division’s imposition of stringent numeric end-of-pipe limitations despite post-LTCP data showing continuous water quality standards (WQS) attainment based on assumption that any combined sewer overflow has the potential to “cause or contribute” to the violation of WQS.

Flushable Wipes

Kimberly-Clark Corp. v. District of Columbia, US District Court for the District of Columbia (Challenge to DC’s law regulating the labeling and flushability of disposable wipes)

Miscellaneous NPDES Permitting Issues

Center for Regulatory Reasonableness v. EPA (Challenge to EPA’s regulatory approach on blending)
Southern California Alliance of Publicly Owned Treatment Works v. EPA (Challenge to the application of certain testing requirements for whole effluent toxicity)

NPDES Permitting Terms / Application of the Permit Shield

San Francisco v. EPA. (Challenge to inclusion of generic “backstop” language in utility NPDES permits requiring that discharges not “cause or contribute” to the violation of applicable water quality standards).

Southern Appalachian Mountain Stewards v. A&G Coal Corp. (Appeal of a ruling that a permittee must have actually disclosed a pollutant in its NPDES permit application in order to invoke the permit shield defense)
Ohio Valley Environmental Coalition et al. v. Fola Coal Company (Challenge addressing the CWA permit shield defense and narrative water quality criteria)

Stormwater Permitting and Fees

City of Wilmington v. U.S. – Dispute over whether the U.S. Army Corps of Engineers had to remit over $5.8 million in unpaid stormwater management fees to the City of Wilmington under Clean Water Act Section 1323.

Maryland Small MS4 Coalition v. Maryland Department of the Environment – Challenge to state-issued NPDES general permit for small MS4 operators that included requirements beyond the maximum extent practicable (MEP) standard and required MS4s to address nonpoint source runoff and other third-party stormwater dischargers that did not flow into or discharge from their systems.
- Maryland Appeals Court Decision Upholding Challenged Terms of General Permit
- NACWA Files Amicus Brief Supporting Maryland MS4s
Center for Regulatory Reasonableness v. EPA (Challenge to EPA’s inclusion of water quality standards in MS4 permitting)

DeKalb County v. United States (Litigation in federal Court of Claims to recover unpaid stormwater fees from federal govt. facilities)
Los Angeles County Flood Control District v. NRDC (Appeal to U.S. Supreme Court over what constitutes a stormwater “discharge” under the Clean Water Act and requires compliance with an NPDES permit)
Maryland Department of the Environment et al. v. Anacostia Riverkeeper et al. (Legal challenge on whether CWA requires MS4 permits to mandate "strict compliance" with water quality standards)
Natural Resources Defense Council v. New York State Department of Environmental Conservation (Legal challenge to New York’s General Municipal Separate Storm Sewer System Permit)
N ortheast Ohio Regional Sewer District v. Bath Township, Ohio. et al. (Legal challenge to local municipal stormwater fee program and use of impervious surface-based billing approach)
United States v. Cities of Vancouver and Renton (Federal litigation in Washington State addressing whether 2011 Stormwater Fee Amendment to the CWA applies to municipal stormwater charges assessed prior to 2011)
Virginia DOT, et al. v. US EPA (Federal litigation in Virginia challenging an EPA “flow TMDL” for municipal stormwater discharge)
Zweig v. MSD St. Louis (Appeal of Missouri state trial court decision invalidating a municipal stormwater fee program based on use of impervious surface)

Total Maximum Daily Loads (TMDLs)

Anacostia Riverkeeper v. EPA (Addresses whether (1) daily load targets in TMDLs must be met on a daily basis, (2) daily TMDL limits must be included in subsequently-renewed POTW NPDES permits and (3) whether TMDLs Must Satisfy Designated Uses and Narrative Criteria in Addition to Numeric Criteria)
American Farm Bureau, et al. v. EPA (Challenge to the final TMDL for the Chesapeake Bay)

Fairfield County, Ohio v. State of Ohio (Permit appeal addressing whether inability to challenge TMDL allocation before it is used to derive permit limit is a violation of due process)
Ohio Valley Environmental Coalition v. Pruitt (Appeal of a federal district court decision requiring EPA to act on constructive submission of TMDLs)

Water Quality Standards

Upper Missouri Waterkeeper v. EPA – Challenge to EPA’s approval of a nutrient variance based in part on claim that variances must result in attainment of the underlying water quality standard.
Long Island Sound Nitrogen Reduction Strategy (EPA Regions 1 and 2 initiative to reduce nutrient loadings to the Sound)

Food and Water Watch, et al. v. EPA (Challenge to water quality trading provisions in final Chesapeake Bay TMDL)
Upper Blackstone Water Pollution Abatement District v. EPA (Appeal of federal NPDES discharge permit containing inappropriate nutrient limits)
Gulf Restoration Network v. EPA (Challenge to EPA denial of petition requesting federal numeric nutrient criteria and TMDLs for all waters in Mississippi River Basin and Northern Gulf of Mexico)

Water Quality Trading

Food & Water Watch PA Permit Challenge (water quality trading challenge)

Water Transfers

Friends of the Everglades v. South Florida Water Management District (Appeal of requirement for NPDES for transfers of natural, untreated water)
Catskill Mountains Chapter of Trout Unlimited Inc., et al. v. U.S. EPA (Appeal from lower federal court decision vacating key elements of EPA’s 2008 Water Transfers Rule) Decided January 2017.

Waters of the United States (WOTUS)

Sackett v. EPA – Supreme Court review of proper scope of federal Clean Water Act jurisdiction over “waters of the United States” (WOTUS).