The United States Supreme Court today issued its opinion in PPL Montana v. Montana Though the case involved state interpretations of navigability of waters in Montana that also flow out of state, when the Supreme Court granted certiorari there was great concern that the court would expand the traditional navigability standards with new interpretations by the federal government under the Clean Water Act. In an opinion authored by Justice Kennedy, the Supreme Court unanimously reversed the Montana Supreme Court which had adopted a liberal interpretation of navigability. The most important aspect of this case is that the Court did not expand the navigability interpretation to such tests as EPA’s famous “float your boat” test. More later. Also thanks to Nick Goldstein with ARTBA for first bringing this to my attention. ARTBA filed a brief in the case and the Court agreed with them. Also, I might mention that Ken Gish in the Stites & Harbison Lexington, KY office worked extensively in the state court proceedings.