Clean Water Act Definition of "Waters of the U.S."
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Clean water is the nation's most valuable natural resource and is relied on for drinking, recreation, manufacturing, energy development, agriculture, commercial fishing, tourism, and many other purposes that are essential to public health and the economy.
Since 1972, the Clean Water Act has protected our health and environment by reducing the pollution in streams, lakes, rivers, wetlands and other waterways. But over the past decade, interpretations of Supreme Court rulings have removed some waters from federal protection, and caused confusion about which waters and wetlands remain protected.
EPA and the U.S. Army Corps of Engineers have sent a draft rule to clarify the jurisdiction of the Clean Water Act to the Office of Management and Budget for interagency review. The proposed rule will provide greater consistency, certainty, and predictability nationwide by providing clarity in determining where the Clean Water Act applies. These improvements are necessary to reduce costs and minimize delays in the permit process and protect waters that are vital to public health, the environment and economy. The process for making these improvements will be transparent, based on the best available science, consistent with the law, and include the opportunity for public input. EPA and the Corps of Engineers have received requests for a rulemaking from members of Congress, state and local officials, industry, agriculture, environmental groups, and the public.
This draft rule takes into consideration the latest peer-reviewed science reflected in a draft science report titled: Connectivity of Streams and Wetlands to Downstream Waters, which presents a review and synthesis of more than 1,000 pieces of relevant peer reviewed scientific literature. EPA's independent Science Advisory Board is soliciting public comment and will hold a public peer review meeting later this year.
This report, when finalized, will provide a scientific basis needed to clarify Clean Water Act jurisdiction, including a description of the factors that influence connectivity and the mechanisms by which connected waters affect downstream waters. Any final regulatory action related to the jurisdiction of the Clean Water Act in a rulemaking will be based on the final version of this scientific assessment, which will reflect EPA's consideration of all comments received from the public and the independent peer review.
The proposed rule is limited to clarifying current uncertainty concerning the jurisdiction of the Clean Water Act that has arisen as an outgrowth of recent Supreme Court decisions. EPA and the Corps are focusing on clarifying protection of the network of smaller waters that feed into larger ones, to keep downstream water safe from upstream pollutants. The agencies are also clarifying protection for wetlands that filter and trap pollution, store water, and help keep communities safe from floods. These improvements will additionally result in important economic benefits for the nation's businesses, agriculture, energy producers, and others who depend on abundant and reliable sources of clean water.
The proposed rule does not propose changes to existing regulatory exemptions and exclusions, including those that apply to the agricultural sector that ensure the continuing production of food, fiber and fuel to the benefit of all Americans. In fact, the proposed rule will enhance the ability of the Clean Water Act and USDA's conservation programs to work in tandem to protect water quality and improve the environment by encouraging expanded participation in conservation programs by farmers and ranchers. It will do so by providing greater clarity on which waters are not subject to Clean Water Act jurisdiction and greater certainty on which activities do not require Clean Water Act permits.
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Previous EPA Statements on Waters of the US
- Clean Water Act Jurisdiction Following the U.S. Supreme Court's Decision in Rapanos v. United States & Carabell v. United States (PDF) December 2, 2008 (13 pp, 1.1MB)
- Questions and Answers Regarding the Revised Rapanos & Carabell Guidance (PDF) (3 pp, 70K)
- Agencies Revise Guidance to Protect Wetlands and Streams - 12/03/08 News Release
- Response to Comments "Clean Water Act Jurisdiction Following the Supreme Court's Decision in Rapanos v. United States & Carabell v. United States Guidance" (PDF) (7 pp, 71K)
- The agencies accepted public comments on the Rapanos guidance until January 20, 2008. Use www.regulations.gov to access guidance comments (Docket number EPA-HQ-OW-2007-0282).
- June 2007 Legal Memorandum (PDF) (12 pp, 149K) discussing Clean Water Act Jurisdiction Following the U.S. Supreme Court Decision in Rapanos v. United States & Carabell v. United States.
- June 2007 Memorandum of Agreement (PDF) (7 pp, 131K) regarding Coordination on Jurisdictional Determinations under Clean Water Act Section 404 in Light of the SWANCC and Rapanos Supreme Court Decisions.
- For additional information, consult the Army Corps of Engineers Regulatory Program
- January 2003 Legal Memorandum (PDF) (4 pp, 54K) discussing the scope of the Clean Water Act jurisdiction in light of the SWANCC ruling and related court decisions.
Relevant Information about Water
- The draft scientific report, Connectivity of Streams and Wetlands to Downstream Waters: A Review and Synthesis of the Scientific Evidence (PDF), synthesizes the peer-reviewed scientific literature pertaining to biological, chemical, and hydrologic connectivity of waters and the effects that small streams, wetlands, and open waters have on larger downstream waters such as rivers, lakes, estuaries, and oceans (331 pp, 11 MB). The draft report is out for public review and comment through November 6, 2013.
- Drinking Water Analysis Relevant to Rapanos Decision is a GIS analysis aimed at illuminating dependence on intermittent, ephemeral, and headwater streams for water to supply public drinking water systems.
- Interactive Drinking Water Map showing the percent of the U.S. population that gets some of its drinking water directly or indirectly from streams that are intermittent, ephemeral or headwaters.
- Map of perennial stream length as a percentage of total stream length by watershed: Low Resolution (659K) or High Resolution (2.22MB)
- Journal of the American Water Resources Association's featured collection on the hydrological connectivity of headwater streams and their contributions to the integrity of downstream waters
- Environmental Law Institute's Clean Water Jurisidictional Handbook (Section Edition) provides an analysis of relevant case law, compilation of related scientific studies, and ELI's set of jurisdictional checklists.
- Field Operations Manual for Assessing the Hydrologic Permanence and Ecological Condition of Headwater Streams
- The Ecological and Hydrological Significance of Ephemeral and Intermittent Streams in the Arid and Semi-arid American Southwest (PDF) (116 pp, 2.6MB)
- NatureServe's Biodiversity Values of Geographically Isolated Wetlands
- Special Issue of the Journal Wetlands on isolated wetlands
- Association of State Wetland Managers Report entitled The SWANCC Decision and State Regulations of Wetlands
- Ducks Unlimited Report entitled The SWANCC Decision: Implications for Wetlands and Waterfowl
- U.S. Fish and Wildlife Service Report entitled Geographically Isolated Wetlands: A Preliminary Assessment of their Characteristics and Status in Selected Areas of the United States
Legal Background on Waters of the US
- Supreme Court decision in Rapanos v. U.S. and Carabell v. U.S. - June 19, 2006 (PDF) (104 pp, 787K)
- Post-Rapanos Caselaw on "Waters of the United States" (PDF) (3 pp, 27K)
- Supreme Court decision in Solid Waste Agency of Northern Cook County v. U.S. Army Corps - January 9, 2001 (PDF) (41 pp, 227K)
- Supreme Court decision in United States v. Riverside Bayview Homes, Inc. - December 4, 1985 (PDF) (10 pp, 161K)
Regulatory Definition of Waters of the U.S.
40 CFR 230.3(s) 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:
- 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.
(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;
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.