On May 2, 2011, the US Environmental Protection Agency (EPA) and the Army Corps of Engineers (Corps) jointly issued a draft of new guidance for determining whether a particular body of water is protected by the Clean Water Act. The two agencies indicated that the reason for the new draft guidance was the significant uncertainty over the scope Clean Water Act’s jurisdiction, in particular, what bodies of water are subject to regulation by the Act. This uncertainty derives in large part from two United States Supreme Court decisions issued in the past decade—Solid Waste Authority of Northern Cook County v. Army Corps of Engineers (2001) 531 U.S. 159 (SWANCC) and Rapanos v. United States (2006) 547 U.S. 715. In SWANCC, the court struck down the “migratory bird rule,” holding that the Corps exceeded its jurisdiction when it extended the definition of navigable waters to include intrastate waters solely based on its use by migratory birds. To further confuse matters, in Rapanos, a fractured court issued three separate opinions regarding the extent of Clean Water Act’s jurisdiction. The agencies’ draft guidance was issued to give field staff more specific assistance in determining whether a particular water feature is protected by the Act. This new guidance, which may be read to expand the agencies’ jurisdiction, will likely be the subject of litigation based on allegations that it is contrary to the Court’s holdings and exceeds the outer boundaries of authority given to the agencies in the Act.

According to the EPA’s website, the agencies interpret the Clean Water Act to regulate traditional navigable waters, interstate waters, wetlands adjacent to either traditional navigable waters or interstate waters, non-navigable tributaries to traditional navigable waters that are relatively permanent (contain water at least seasonally), and wetlands that directly abut relatively permanent waters. Additionally, tributaries to traditional navigable waters or interstate waters, wetlands adjacent to jurisdictional tributaries to traditional navigable waters or interstate waters, and waters that fall under the “other waters” category will also be regulated if it is determined that they have a “significant nexus” to traditional navigable water or interstate water. Under this “significant nexus” standard, agencies would examine a water feature’s connection to traditional navigable waters and determine whether that feature, alone or in combination with similarly situated water features, has an effect on the chemical, physical, or biological integrity of traditional navigable waters or interstate waters that is more than “speculative” or “insubstantial.” The draft guidance also extends tributaries to interstate and “other waters,” providing protection to bodies of water that were previously vulnerable to contamination and pollution.

If enacted as currently written, the draft guidance will result in significant expansion of the agencies’ scope of jurisdiction because the guidance takes a broad approach to what constitutes a “significant nexus” between water bodies. Both agencies are aware of the expanded jurisdiction, noting that “current practice [2008-2010] may be under-representing Clean Water Act jurisdiction.” Presumably, the guidance is intended to rectify this under-representation. Public comments on the proposed draft guidance are currently being accepted through July 1, 2011. Once finalized, the draft guidance will supersede previously issued guidance on the scope of “waters of the United States” regulated under the Act.