## Facts

- The Clean Water Act (CWA) prohibits discharging dredged or fill material into “navigable waters,” defined as “waters of the United States,” without a permit.
- The U.S. Army Corps of Engineers administered the dredge-and-fill permitting program and asserted jurisdiction over, among other things, tributaries and wetlands “adjacent” to covered waters, including wetlands separated by barriers.
- John A. Rapanos filled wetlands on several Michigan properties to prepare them for development without a CWA permit, despite warnings and cease-and-desist orders.
- The Rapanos wetlands were near man-made drains or ditches that ultimately carried water to traditional navigable waters.
- June and Keith Carabell sought to fill a Michigan wetland to build condominiums; the wetland was separated from a drainage ditch by an earthen berm, but the Corps treated it as “adjacent” and denied a permit.
- The drainage ditch connected through other waterways to Lake St. Clair, a traditional navigable water.

## Issues

1. What limits the CWA’s term “waters of the United States” places on federal jurisdiction over nonnavigable tributaries and wetlands.
2. Whether wetlands connected to navigable waters only through drains, ditches, or indirect hydrologic connections fall within CWA jurisdiction.
3. What legal standard governs when wetlands are sufficiently connected to traditional navigable waters to require a federal permit for discharges of fill material.

## Decision

- The Supreme Court vacated the Sixth Circuit’s judgments and remanded both cases for further proceedings.
- No single opinion commanded a majority on the proper test for “waters of the United States.”
- A four-Justice plurality concluded that covered waters include relatively permanent bodies of water (not merely intermittent or ephemeral drainage features) and that wetlands are covered only when they have a continuous surface connection to such waters, making them practically indistinguishable from the covered water.
- Justice Kennedy concurred in the judgment and would find jurisdiction where wetlands (alone or with similarly situated lands) have a “significant nexus” to traditional navigable waters—i.e., a connection that significantly affects the chemical, physical, or biological integrity of those downstream waters.
- Four dissenting Justices would have affirmed and would have deferred to the Corps’ broader regulatory approach.

## Legal Principles

- “Waters of the United States” does not have a single controlling definition from this case; the Court produced competing frameworks and required case-specific application on remand.
- Plurality framework: CWA jurisdiction extends to relatively permanent waters forming geographic features (such as streams, rivers, lakes, and similar waters) and to wetlands only when there is a continuous surface connection to such waters; intermittent or ephemeral channels that primarily drain rainfall are excluded.
- Kennedy framework: CWA jurisdiction extends to wetlands with a “significant nexus” to navigable-in-fact waters, meaning the wetlands significantly affect downstream water integrity; jurisdiction may require factual findings about ecological and hydrologic effects.
- After remand, lower courts commonly treated Justice Kennedy’s “significant nexus” approach as the operative standard for evaluating jurisdiction in the absence of a majority rule.

## Conclusion

The Court set aside the Sixth Circuit rulings and required renewed jurisdictional analysis under a divided set of approaches, with the leading options being the plurality’s relatively-permanent-waters and continuous-surface-connection test and Justice Kennedy’s significant-nexus test for wetlands tied to traditional navigable waters.


Rapanos v. United States, 547 U.S. 715 (2006)