PPL Montana, LLC v. Montana
United States Supreme Court
132 S.Ct. 1215 (2012)
PPL Montana (plaintiff) operated hydroelectric dams, including several along the Missouri River's Great Falls reach -- a stretch with major waterfalls that even Lewis and Clark's expedition had to portage around -- and sought a declaration that Montana (defendant) did not own the underlying riverbeds; Montana counterclaimed under the equal-footing doctrine, and the trial court and Montana Supreme Court both ruled for the state, awarding $41 million in compensation, reasoning that a "short interruptions" analysis and current recreational river use showed the river was navigable overall at statehood in 1889.
Whether, under the equal-footing doctrine, states gain title to lands submerged beneath river segments determined to be navigable in fact at the time of statehood.