The U.S. Army Corps of Engineers and the Environmental Protection Agency jointly issued a revised guidance document on December 3, 2008 that provides additional information on the scope of “jurisdictional waters” under the Clean Water Act. In June of 2007, the agencies published their first guidance document that attempts to interpret The United States Supreme Court’s fractured decision in Rapanos v. United States, 126 S. Ct. 2208 (2006), which caused considerable confusion over the scope of “jurisdictional waters.” Following Rapanos, jurisdictional waters include both waters that are navigable in the traditional sense and those tributaries and wetlands that have a “significant nexus” to navigable waters. The guidance document is designed to assist in determining when wetlands and small tributaries will be considered jurisdictional waters.

The process and parameters for making “jurisdictional determinations” or “JDs” are particularly important for the coal industry. Mining operations, particularly valley-fills in the Appalachian region, will often have some degree of impact on areas that may be considered “jurisdictional waters” and therefore require what is known as a Section 404 permit from the Corps.

The December 2008 guidance makes essentially three changes to the original guidance document. First, it clarifies that jurisdictional “traditional navigable waters” are broader than the waters governed by Section 10 of the Rivers and Harbors Act. For example, waters that are susceptible to future commercial navigation based on their size, depth, and flow velocity are considered jurisdictional, in addition to waters historically used for commercial navigation.

Second, the rule slightly modifies the methodology for determining the scope of jurisdiction over upstream tributaries of traditionally navigable waters - known as the “relevant reach.” In general, the Corps asserts jurisdiction over non-navigable tributaries of traditionally navigable waters that are relatively permanent where the tributaries typically flow year-round or have continuous flow on a seasonal basis. When considering whether flow is sufficient to qualify as “relatively permanent”, the Corps may now consider the portion of the tributary that “best characterizes” its flow, rather than just the farthest downstream point (where it flows into another stream).

Third, the agencies clarify that wetlands will automatically be considered jurisdictional waters if they are "adjacent" to tributaries of traditional navigable waters, meaning that they exhibit any one of following criteria: (1) have an “unbroken surface or shallow sub-surface connection to jurisdictional waters,” which may be intermittent; (2) are “physically separated from jurisdictional waters by man-made dikes or barriers, natural river berms, beach dunes, and the like” or (3) “their proximity to a jurisdictional water is reasonably close, supporting a science-based inference that such wetlands have an ecological interconnection with jurisdictional waters.” Any one of these findings will obviate the need for any further findings by the Corps to support jurisdiction. This jurisdictional basis for wetlands is an attempt to implement the “significant nexus” test created by the Rapanos decision. Under that test, wetlands are considered jurisdictional “if the wetlands, ether alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable.’”

Although designed to identify “those waters over which the agencies will assert jurisdiction” under the Clean Water Act, neither the Corps, EPA, or the regulated community is legally bound by the guidance. JDs are inherently site specific, and the guidance may not apply to all situations. A copy of the guidance document is available from EPA at the following link: