531 U.S. 159 (2001) (U.S. Supreme Court)
SWANCC is a foundational case at the intersection of environmental law, administrative law, and federalism. The decision limits the scope of federal jurisdiction under the Clean Water Act (CWA) by rejecting the U.S.
Does the Clean Water Act's definition of "navigable waters" as "waters of the United States" authorize the Army Corps of Engineers to assert § 404 jurisdiction over isolated, non-navigable, intrastate ponds based solely on their use by migratory birds (the Migratory Bird Rule)?
The Clean Water Act does not extend § 404 jurisdiction to isolated, non-navigable, intrastate waters based solely on their use by migratory birds. Absent a clear statement from Congress, courts will not construe the CWA to intrude into traditional state authority over land and water use. Agency interpretations that would significantly alter the federal-state balance or raise serious constitutional questions are not entitled to deference and will be rejected if not supported by the statute's text and structure.
No. The Supreme Court reversed, holding that the Corps lacked authority under the CWA to regulate isolated, non-navigable, intrastate ponds based solely on the Migratory Bird Rule.
SWANCC is a cornerstone WOTUS case limiting federal reach under the Clean Water Act. It invalidated the Migratory Bird Rule and underscored that the term "navigable" imposes real constraints on federal jurisdiction. The case is central to law students for three reasons: (1) statutory interpretation and canons—textual limits, federalism clear-statement, and constitutional avoidance; (2) administrative law—constraints on Chevron deference when an agency interpretation would significantly intrude on state authority without clear congressional authorization; and (3) environmental federalism—preserving primary state control over isolated waters and land-use decisions. SWANCC paved the way for later disputes in Rapanos v. United States (2006) and more recent WOTUS rulemakings and decisions, where the Court continued to grapple with the scope of federal water protections.