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Clean Water Act Definition of "Waters of the United States"

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This page is designed to provide updates and background information regarding the scope of " Waters of the United States" protected under the Clean Water Act.

On June 5, 2007, the Environmental Protection Agency (EPA) and the Department of the Army issued guidance clarifying Clean Water Act (CWA) jurisdiction following the U.S. Supreme Court’s decision in the consolidated cases Rapanos v. United States and Carabell v. United States. The agencies received 66,047 public comments on the Rapanos Guidance (65,765 form letters, 282 non-form letters), from States, environmental and conservation organizations, regulated entities, industry associations, and the general public. EPA and the Department of the Army jointly reviewed the comments and released a revised version of the guidance on December 2, 2008 in consideration of those comments and consistent with the agencies' experience implementing the guidance. The revised guidance and a set of questions and answers on the guidance are posted below.

Definition of "Waters of the United States"

40 CFR 230.3(s) The term waters of the United States means:

  1. 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;
  2. All interstate waters including interstate wetlands;
  3. All other waters such as intrastate lakes, rivers, streams (including intermittent streams), mudflats, sandflats, wetlands, sloughs, prairiepotholes, wet meadows, playa lakes, or natural ponds, the use, degradation or destruction of which could affect interstate or foreign commerce including any such waters:
      (i) Which are or could be used by interstate or foreign travelers for recreational or other purposes; or
      (ii) From which fish or shellfish are or could be taken and sold in interstate or foreign commerce; or
      (iii) Which are used or could be used for industrial purposes by industries in interstate commerce;
  4. All impoundments of waters otherwise defined as waters of the United States under this definition;
  5. Tributaries of waters identified inparagraphs (s)(1) through (4) of this section;
  6. The territorial sea;
  7. 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.

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