By Robert Uram, Ella Foley-Gannon and Aaron Foxworthy

On June 5, 2007, the Army Corps of Engineers (Corps) and the U.S. Environmental Protection Agency (US EPA) published long-awaited guidance on the United States Supreme Court’s decisions in Rapanos v. United States and Carabell v. United States Army Corps of Engineers.  Posted on the agencies’ respective web sites, the guidance sets out their interpretation of the Rapanos and Carabell decisions, particularly their effects on the agencies’ regulatory jurisdiction under Section 404 of the Clean Water Act (CWA Jurisdiction).

The key documents posted are:  Rapanos Guidance, a Memorandum of Understanding, a Questions and Answers Sheet (EPA), a Questions and Answer Sheet (Corps) and Key Points (Corps).  The Corps has also issued a U.S. Army Corps of Engineers Jurisdictional Determination (JD) Form Instructional Guidebook that contains detailed information on how to apply the Guidance.The effect of the Guidance will become clearer as the Corps implements it, but almost certainly, the Guidance will result in the Corps disclaiming CWA Jurisdiction over at least some ephemeral streams, drainage ditches and adjacent wetlands that were regularly regulated before the Supreme Court’s decisions in the Rapanos and Carabell.  As for existing CWA Jurisdictional determinations, the Corps states in its Questions and Answers Sheet that it will not revisit jurisdictional decisions made prior to the two Supreme Court decisions, but will revisit a jurisdictional determination completed after the decisions if the applicant requests revisitation. Lastly, in the accompanying Federal Register Notice, the agencies have provided for a six-month comment period covering the Guidance.  In seeking public comments, the agencies announced that, based on comments received during the initial six months of applying the new guidance, further revisions may be forthcoming.

The agencies will immediately rely on the new Guidance in making determinations of CWA Jurisdiction. 

To briefly summarize the Supreme Court’s decisions in Rapanos and Carabell, the court considered the extent of CWA Jurisdiction over wetlands and other waters of the United States that are not navigable waters in the traditional sense.No single opinion commanded a majority of the Court.  A plurality of four Justices voted to clarify that the language of the Act restricts the extent of the agencies’ CWA Jurisdiction to (a) waters that are traditionally navigable, (b) wetlands immediately adjacent to such waters, (c) relatively permanent tributaries to such traditionally navigable waters, and (d) wetlands that have a continuous surface connection to such tributaries.  A fifth Justice, Justice Kennedy, voted with the plurality to remand the Corps’ determinations, but based on a different standard than the plurality’s more restrictive view.  In Justice Kennedy’s estimation, before asserting jurisdiction, the Corps must first determine whether the potentially jurisdictional area has a significant effect on the chemical, physical and biological integrity of traditionally navigable waters.  According to Justice Kennedy, this "significant nexus" test is not based on an aquatic feature-by-feature analysis, but on a case-by-case review of similarly situated, potentially jurisdictional features in a "region."

The new Guidance advises staff that determinations must satisfy either the plurality standard or Justice Kennedy’s substantial nexus standard before asserting CWA Jurisdiction over non-navigable waters of the United States.  In accordance with the Guidance, CWA Jurisdiction will generally be as follows:

A. The Corps and US EPA will assert jurisdiction over the following waters:

  • Traditional navigable waters
  • Wetlands adjacent to traditional navigable waters
  • Non-navigable tributaries of traditional navigable waters that are relatively permanent where the tributaries typically flow year-round or have continuous flow at least seasonally (e.g., typically three months)
  • Wetlands that directly abut such tributaries

B. The Corps and US EPA will decide jurisdiction over the following waters based on a fact-specific analysis to determine whether they have a significant nexus with a traditional navigable water:

  • Non-navigable tributaries that are not relatively permanent
  • Wetlands adjacent to non-navigable tributaries that are not relatively permanent
  • Wetlands adjacent to but that do not directly abut a relatively permanent non-navigable tributary

C. The agencies generally will not assert jurisdiction over the following features:

  • Swales or erosional features (e.g., gullies, small washes characterized by low volume, infrequent, or short duration flow)
  • Ditches (including roadside ditches) excavated wholly in and draining only uplands and that do not carry a relatively permanent flow of water

D. The agencies will apply the significant nexus standard as follows:

  • A significant nexus analysis will assess the flow characteristics and functions of the tributary itself and the functions performed by all wetlands adjacent to the tributary to determine if they significantly affect the chemical, physical and biological integrity of downstream traditional navigable waters
  • Significant nexus includes consideration of hydrologic and ecologic factors.

The Guidance also includes requirements for the Corps to document in detail the basis for its conclusions, provides for public availability of decisions, and establishes an elaborate Corps-EPA coordination and review process for those CWA Jurisdictional determinations that involve the application of the significant nexus test.  Under the coordination process, all "significant nexus determinations" will be reviewed by both EPA regional and headquarters offices and the Corps’ headquarters.  The process has specified timelines and local offices will not be able to finalize a delineation for these categories until the review process is complete.

For further information on how the new Guidance may affect aquatic features of concern to you, please contact Robert Uram, Ella Foley-Gannon, or Aaron Foxworthy.  Mr. Uram and Ms. Foley-Gannon are partners in the Real Estate, Land Use and Natural Resources Practice Group in Sheppard Mullin’s San Francisco Office, and Mr. Foxworthy is an associate in the Real Estate, Land Use and Natural Resources Practice Group in Sheppard Mullin’s San Francisco Office.