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Water: Wetlands

Clean Water Act Definition of "Waters of the U.S."

The U.S. Environmental Protection Agency and U.S. Army Corps of Engineers jointly released a proposed rule to clarify protection under the Clean Water Act for streams and wetlands that form the foundation of the nation's water resources. Determining Clean Water Act protection for streams and wetlands became confusing and complex following Supreme Court decisions in 2001 and 2006. The proposed rule was published in the Federal Register on Monday, April 21, 2014. The public comment period will be open for 182 days and will close on Monday, October 20, 2014.



Streams and Wetlands

Additional Information

Public Comment Period Open Until October 20, 2014

Learn more about EPA and the Corps' waters of the United States proposed rule.

Background Information

Select from the list below to expand the view and read further information on that topic.

Current Guidance on Waters of the U.S.

Relevant Information about Water

Legal Background on Waters of the U.S.

Current Regulatory Definition of Waters of the U.S.

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, 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:
  4. (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;

  5. All impoundments of waters otherwise defined as waters of the United States under this definition;
  6. Tributaries of waters identified in paragraphs (s)(1) through (4) of this section;
  7. The territorial sea;
  8. 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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