Definition of "Waters of the United States" under the Clean Water Act
- Current Implementation of Waters of the United States
- Supreme Court Rulings Related to Waters of the United States
- Clean Water Rule
On October 22, 2019, the Environmental Protection Agency and Department of the Army (the agencies) published a final rule (Step One) to repeal the 2015 Rule defining “waters of the United States” and re-codify the regulatory text that existed prior to the 2015 Rule. The final Step One rule became effective on December 23, 2019. Read the final Step One rule.
- includes four simple categories of jurisdictional waters,
- provides clear exclusions for many water features that traditionally have not been regulated, and
- defines terms in the regulatory text that have never been defined before.
Congress, in the Clean Water Act, explicitly directed the Agencies to protect “navigable waters.” The Navigable Waters Protection Rule regulates these waters and the core tributary systems that provide perennial or intermittent flow into them. The final rule fulfills Executive Order 13788 and reflects legal precedent set by key Supreme Court cases as well as robust public outreach and engagement, including pre-proposal input and comments received on the proposed rule. Read the pre-publication version of the final rule.
If a state, tribe, or an entity has specific questions about a pending jurisdictional determination or permit, please contact a local U.S. Army Corps of Engineers District office or the EPA.
Current Regulatory Definition of “Waters of the United States” Recodified in the Step One Rule
Until the Navigable Waters Protection Rule takes effect, the Step One rule is in effect. 40 CFR 230.3(s) indicates that the term “waters of the United States” means:
- All waters which are currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide;
- All interstate waters including interstate wetlands;
- All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters:
- Which are or could be used by interstate or foreign travelers for recreational or other purposes; or
- (From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or
- Which are used or could be used for industrial purposes by industries in interstate commerce;
- All impoundments of waters otherwise defined as waters of the United States under this definition;
- Tributaries of waters identified in paragraphs (s)(1) through (4) of this section;
- The territorial sea;
- Wetlands adjacent to waters (other than waters that are themselves wetlands) identified in paragraphs (s)(1) through (6) of this section.
Waste treatment systems, including treatment ponds or lagoons designed to meet the requirements of CWA (other than cooling ponds as defined in 40 CFR 423.11(m) which also meet the criteria of this definition) are not waters of the United States.
Waters of the United States do not include prior converted cropland. Notwithstanding the determination of an area’s status as prior converted cropland by any other federal agency, for the purposes of the Clean Water Act, the final authority regarding Clean Water Act jurisdiction remains with EPA.
Guidance Documents on the Definition of "Waters of the United States"
Rapanos v. United States & Carabell v. United States
In 2007 and again in 2008, the agencies developed guidance for implementing the above definition of "waters of the United States" under the Clean Water Act following the U.S. Supreme Court's decision in the consolidated cases Rapanos v. United States and Carabell v. United States.
- Clean Water Act Jurisdiction Following the U.S. Supreme Court's Decision in Rapanos v. United States & Carabell v. United States - December 2, 2008
- Questions and Answers Regarding the Revised Rapanos & Carabell Guidance
- June 2007 Legal Memorandum discussing Clean Water Act Jurisdiction Following the U.S. Supreme Court Decision in Rapanos v. United States & Carabell v. United States. This guidance is superseded by the 2008 guidance.
- June 2007 Memorandum of Agreement regarding Coordination on Jurisdictional Determinations under Clean Water Act Section 404 in Light of the SWANCC and Rapanos Supreme Court Decisions
- Appendix D: Legal Definition of Traditional Navigable Waters
- For additional information, consult the Army Corps of Engineers Regulatory Program
Solid Waste Agency of Northern Cook County (SWANCC) v. United States
In 2001 and again in 2003, the agencies developed guidance to address the above definition of "waters of the United States" under the Clean Water Act following the SWANCC Supreme Court decision.
- January 2003 Legal Memorandum discussing the scope of the Clean Water Act jurisdiction in light of the SWANCC ruling and related court decisions.
- January 2001 Legal Memorandum describing which aspects of the regulatory definition of "waters of the United States" are and are not affected by SWANCC. This guidance is superseded by the 2003 guidance.
1989 Memorandum of Agreement - Allocates responsibilities between EPA and the Corps for determining the geographic scope of the Section 404 program and the applicability of exemptions from regulation under Section 404(f).
1979 "Civiletti" Memorandum - U.S. Attorney General opinion on ultimate administrative authority under Section 404 to determine the reach of navigable waters and the meaning of Section 404(f).
June 24, 2016 Memorandum - Provides interim guidance to field staff in light of the Hawkes ruling in the Supreme Court.
Clean Water Act Section 404 and Agriculture - Includes the 1990 Memorandum to the Field and the Memorandum withdrawing the Interpretive Rule.
- Supreme Court decision in Rapanos v. U.S. and Carabell v. U.S. - June 19, 2006
- Post-Rapanos Caselaw on "Waters of the United States"
- Supreme Court decision in Solid Waste Agency of Northern Cook County v. U.S. Army Corps - January 9, 2001
- Supreme Court decision in United States v. Riverside Bayview Homes, Inc. - December 4, 1985
On February 28, 2017, the President issued an Executive Order directing the Administrator of EPA and the Assistant Secretary of the Army for Civil Works to review the 2015 Clean Water Rule ("2015 Rule") and publish for notice and comment a proposed rule rescinding or revising the 2015 Rule, as appropriate and consistent with law. On October 22, 2019, the EPA and the Department of Army published a final rule to repeal the 2015 Rule and recodify the agencies' pre-existing regulatory definition of "waters of the United States." This final rule became effective on December 23, 2019. This rule will be replaced by the Navigable Waters Protection Rule upon its effective date, 60 days after publication in the Federal Register. On January 23, 2020, the EPA and the Department of the Army (Army) finalized the Navigable Waters Protection Rule to define “waters of the United States” (WOTUS).
The following documents are associated with the 2015 Clean Water Rule and are provided for informational purposes only.
- Federal Register Notice - Clean Water Rule: Definition of "Waters of the United States"
- Clean Water Rule: Definition of “Waters of the United States” at 40 CFR 230.3
- To see the Clean Water Rule website, please visit the EPA Web Archive.
- Associated Documents:
- Technical Support Document for the Clean Water Rule: Definition of Waters of the United States
- Economic Analysis of the EPA-Army Clean Water Rule
- Environmental Assessment
- Response to Comments
- Final report: Connectivity of Streams and Wetlands to Downstream Waters: A Review and Synthesis of the Scientific Evidence
- Science Advisory Board review of the draft report
- Science Advisory Board Consideration of the Adequacy of the Scientific and Technical Basis of the Proposed Rule