On March 25, 2014, EPA and the Army Corps of Engineers issued a pre-publication release of the much-anticipated proposed rule to define the jurisdictional “Waters of the United States” that are regulated under the Clean Water Act (CWA). The proposed rule is aimed at providing clarity and certainty to “jurisdictional water” determinations in the wake of the uncertainty resulting from the 2006 U.S. Supreme Court ruling in Rapanos v. U.S. To that end, the rule proposes to minimize the number of case-specific determinations that will be required by codifying specific categories of waters that will automatically be included or excluded as jurisdictional “waters of the United States.”