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EPA’s Clean Water Act Guidance: The EPA Steps Back Into the Debate About the Extent of Waters Covered by the Clean Water Act

April 29, 2011

After years of debate in the courts over the scope of Clean Water Act coverage, earlier this week the Environmental Protection Agency (EPA) issued a draft guidance intended to clarify this issue.  The guidance describes how the EPA and U.S. Army Corps of Engineers will identify waters protected by the Clean Water Act (CWA), including how the agencies will implement the Supreme Court’s decisions addressing jurisdictional waters, which are those protected by the CWA.  The EPA developed this guidance in response to its concern that, after U.S. Supreme Court rulings on the issue, certain waters lacked protection and that significant uncertainty remained as to which waters were protected. 

EPA’s guidance is intended for use by EPA and Corps field staff; it is not a rule.  Consequently, it is not binding and lacks the force of law.  Federal agencies will nonetheless likely rely upon the guidance to explain and clarify their understanding of existing requirements under the CWA.  Notably, EPA states in the guidance that it expects to later proceed with formal rulemaking to further clarify the regulatory definition of the term “waters of the United States” for purposes of CWA coverage. 

The guidance provides EPA’s opinion on which waters are protected by the CWA.  EPA notes that each jurisdictional determination will be made on a “case-by-case basis considering the facts and circumstances of the case and consistent with applicable statutes, regulations, and case law.”  The guidance concludes that certain waters are always protected by the CWA.  Those waters include:  (1) traditional navigable waters; (2) interstate waters; (3) wetlands adjacent to either traditional navigable waters or interstate waters; (4) non-navigable tributaries to traditional navigable waters that are relatively permanent, meaning they contain water at least seasonally; and (5) wetlands that directly abut relatively permanent waters.   

Additionally, pursuant to the guidance, some waters are protected if a fact-specific analysis determines they have a “significant nexus” to a traditional navigable water or interstate water.  Waters have a “significant nexus” if they, “either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity of traditional navigable waters or interstate waters.”  The following waters are protected if they have a “significant nexus” to traditional navigable waters or interstate waters:  (1) tributaries (that are not relatively permanent) to traditional navigable waters or interstate waters; (2) wetlands adjacent to jurisdictional tributaries to traditional navigable waters or interstate waters; and (3) waters that fall under the “other waters” category of the regulations, which are waters such as instrastate waters, wet meadows, prairie potholes, sloughs, ponds, that “the use, degradation or destruction of which could affect interstate or foreign commerce.”  EPA notes that, “[i]n light of the challenges in applying the significant nexus standard to geographically isolated other waters, the agencies have identified physical proximity as an important factor when conducting a significant nexus analysis for such waters.”

Finally, the guidance describes aquatic areas that are not generally protected by the CWA.  That list includes, among others: artificially irrigated areas that would revert to upland should irrigation cease; artificial lakes or ponds created by excavating and/or diking dry land and used exclusively for purposes such as stock watering, irrigation, settling basins, or rice growing; groundwater drained through subsurface drainage systems; and erosional features (e.g., gullies), and swales and ditches that are not tributaries or wetlands.      

EPA’s guidance has aroused significant disagreement.  Stirring the most controversy is EPA’s interpretation of waters having a “significant nexus” to traditional navigable waters or interstate waters.  Many believe EPA’s guidance expands CWA coverage well beyond the U.S. Supreme Court’s decisions and the initial intent of the Act.  It will be interesting to watch how the interpretation changes, if at all, between now and when EPA eventually drafts regulations on this issue.  It does not appear that the debate over Clean Water Act jurisdiction will end any time too soon. 

The draft guidance is open for 60 days of public comment to allow stakeholders to provide input and feedback before it is finalized.  More information can be found on EPA’s website.

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