In December 2005, Atlantic Legal Foundation, partnering with New England Legal Foundation, filed an amicus brief in the United States Supreme Court in Rapanos v. United States, a case which may clarify whether the U.S. Army Corps of Engineers (the "Corps") has the authority under the Clean Water Act ("CWA") to regulate the dredging and filling of inland wetlands.

  On June 19, 2006 a fractured Court (there was no majority opinion, the case being decided by a plurality opinion by Justice Scalia, joined by Chief Justice Roberts, Justice Thomas, and Justice Alito) rejected the Government’s “hydrologic connection” theory, and held that: 

 (1) The phrase “the waters of the United States” includes only those relatively permanent, standing or continuously flowing bodies of water “forming geographic features” that are described in ordinary parlance as “streams,” “oceans, rivers, [and] lakes,” and does not include channels through which water flows intermittently or ephemerally, or channels that periodically provide drainage for rainfall. The Corps’ expansive interpretation of that phrase is thus not “based on a permissible construction of the statute.” 

 (a)  While the meaning of “navigable waters” in the CWA is broader than the traditional definition found in earlier cases, the CWA authorizes federal jurisdiction only over “waters.” The use of the definite article “the” and the plural number “waters” show plainly that the Act does not refer to water in general, but more narrowly to water as found in streams, oceans, rivers, and lakes and those terms all connote relatively permanent bodies of water, as opposed to ordinarily dry channels through which water occasionally or intermittently flows.

  (b)  The Act’s use of the traditional phrase “navigable waters” confirms that the CWA confers jurisdiction only over relatively permanent bodies of water. Traditionally, such “waters” included only discrete bodies of water, and the term still carries some of its original substance. The CWA itself categorizes the channels and conduits that typically carry intermittent flows of water separately from “navigable waters,” including them in the definition of “ ‘point sources.” Moreover, only the narrower definition of “waters” is consistent with CWA’s stated policy “to recognize, preserve, and protect the primary responsibilities and rights of the States … to plan the development and use … of land and water resources … .” In addition, “the waters of the United States” hardly qualifies as the clear and manifest statement from Congress which would be needed to authorize intrusion into such an area of traditional state authority as land-use regulation and to authorize federal action that stretches the limits of Congress’s commerce power.

  (2)  A wetland may not be considered “adjacent to” remote “waters of the United States” based on a mere hydrologic connection and only those wetlands with a continuous surface connection to bodies that are “waters of the United States” in their own right are covered by the Act. Establishing coverage of the Rapanos and Carabell sites requires finding that the adjacent channel contains a relatively permanent “water of the United States,” and that each wetland has a continuous surface connection to that water, making it difficult to determine where the water ends and the wetland begins.

 Justice Kennedy agreed that the Sixth Circuit erred and that the hydrologic connection theory goes too far, so he joined the plurality for reversal, but he would have the Sixth Circuit apply all of the factors in two leading earlier cases. His preferred test would focus on whether the given wetlands have a “significant nexus” to waters that are, or reasonably could be, made navigable.(Some commentators, e.g. Linda Greenhouse in the June 20, 2006 edition of The New York Times, believe that the decision is a victory for environmentalists, emphasizing Justice Kennedy’s concurrence. We disagree, although to be sure the way in which the Rapanos decision is applied by the lower courts is not predictable.)

  Justice Stevens wrote the main dissent, which all the remaining justices joined. Stevens’s dissent argues that the Corps’s interpretation should be given deference. Breyer filed an additional brief view as well. 

 Both Rapanos and Carabell were reversed and remanded.