Respondents were Vermont landowners who owned property along the Vermont shore of Lake Champlain. They alleged that petitioner International Paper Company's paper mill in Ticonderoga, New York, discharged pollutants into Lake Champlain pursuant to a National Pollutant Discharge Elimination System (NPDES) permit issued under New York's EPA-approved program. According to respondents, the discharges caused offensive odors, slime, discoloration, and deposits that interfered with their use and enjoyment of property and diminished property values on the Vermont side of the lake. Respondents filed a class action in federal court (the District of Vermont) asserting Vermont common-law claims—including nuisance, trespass, and negligence—and seeking damages and injunctive relief. International Paper argued that the Clean Water Act preempted application of Vermont law to an out-of-state source. The district court dismissed; the Second Circuit reversed, holding that the CWA's savings clauses preserved affected-state common-law remedies. The Supreme Court granted certiorari.
Does the Clean Water Act preempt application of an affected state's common-law nuisance (and related tort) claims against an out-of-state point source, or may injured parties rely on the affected state's law to obtain relief?
The Clean Water Act establishes a comprehensive, permit-based regime (33 U.S.C. § 1342) for regulating point-source discharges and channels primary regulatory authority to the source state or EPA, while preserving certain state roles through savings clauses (33 U.S.C. §§ 1365(e), 1370). The Act preempts application of an affected state's common law to an out-of-state point source because such extraterritorial application would conflict with the uniform permitting scheme and subject permittees to inconsistent, multiple standards. However, the CWA does not preempt state common-law claims brought under the law of the source state, so long as those claims and remedies do not conflict with or undermine the Act or the terms of the applicable NPDES permit.
The Clean Water Act preempts application of Vermont common law to an out-of-state source discharging from New York into Lake Champlain. Respondents may proceed, if at all, only under New York (the source state's) common law. The judgment was reversed and the case remanded to allow amendment to assert claims under New York law.
1) Comprehensive federal-state framework and uniformity: The CWA's core is the NPDES permitting program, which places primary authority over point-source effluent limits with the EPA or the source state operating an EPA-approved program (33 U.S.C. § 1342). Congress designed the program to subject each discharge to a single set of effluent limitations administered through one permit. Allowing affected states to apply their own common law to out-of-state sources would impose multiple, potentially inconsistent standards on a single discharger, undermining the uniformity the CWA seeks to ensure. 2) Affected-state participation is structured and limited: The Act gives affected states defined roles—such as the § 401 certification process for federal permits (33 U.S.C. § 1341) and comment/objection opportunities in state-issued permits (33 U.S.C. § 1342(d))—but it does not confer authority on affected states to regulate out-of-state sources directly. Permitting affected-state nuisance law to control an out-of-state source would allow those states to achieve indirectly what Congress prohibited directly. 3) Savings clauses do not authorize extraterritorial state law: Section 510 (33 U.S.C. § 1370) preserves state authority to adopt or enforce more stringent standards, and § 505(e) (33 U.S.C. § 1365(e)) preserves other remedies in law or equity. Read in context, these provisions preserve state authority and remedies only to the extent they do not conflict with the CWA's structure. They do not permit an affected state to impose its law on out-of-state dischargers in a manner that would disrupt the single-permit system or create a patchwork of obligations. 4) Source-state law survives and fits the CWA scheme: Permitting suits under the source state's common law aligns with the Act's cooperative federalism design, because the source state participates in and can influence permitting and may choose to adopt more stringent controls for sources within its borders. Consequently, common-law nuisance claims under source-state law are preserved, subject to the constraint that remedies cannot contradict the federal permit or otherwise be inconsistent with the Act's objectives. 5) Remedies and consistency with permits: While the Court did not categorically bar damages or injunctive relief, it emphasized that any state-law remedy must not require action incompatible with the NPDES permit or otherwise subvert the federal scheme. Source-state law may provide compensation or additional constraints, but courts must ensure that relief does not effectively rewrite permit conditions or impose conflicting effluent limits. 6) Relationship to Milwaukee II: Building on City of Milwaukee v. Illinois (Milwaukee II), which held that the CWA displaced federal common-law nuisance for interstate water pollution, the Court clarified that state common law is not eliminated wholesale. Rather, the CWA permits state-law claims, but only under the source state's law to prevent the very interstate inconsistency that concerned Congress.
Ouellette is a cornerstone in environmental federalism and preemption doctrine. It teaches that: (1) comprehensive federal regulatory schemes can coexist with state tort law, but only within carefully defined boundaries; (2) savings clauses are read in harmony with statutory structure and objectives, not as carte blanche to undermine them; and (3) in interstate pollution disputes, the choice of law is the source state's law. For practitioners and students, the case has direct consequences for forum selection, pleading strategy (including choice-of-law allegations), and the scope of available remedies alongside NPDES permitting.
International Paper Co. v. Ouellette harmonizes the Clean Water Act's comprehensive, permit-centered approach with the historical availability of state common-law remedies. By restricting applicable tort law to that of the source state, the Court preserved a meaningful role for state law while preventing a patchwork of inconsistent standards that could destabilize the uniform NPDES regime.