Mississippi v. Tennessee, et al.
Mississippi v. Tennessee, et al. (U.S. Supreme Court, Nov. 22, 2021): In a unanimous decision, the Supreme Court dismissed a claim by Mississippi seeking money damages against Tennessee for pumping water out of an aquifer that runs under the land of both states. The Court decided that the water in the aquifer should be apportioned equitably between the states because although states typically have complete control over waters contained within their borders, the same is not true regarding waters that flow between states. While this method of apportionment is often used to decide disputes over water between states, this decision marks the first time the rule was applied to water in an aquifer, an area of groundwater held in rocks. The Court did not determine what an equitable apportionment of the water would be because Mississippi asked only for money damages and opposed apportionment. Read the full decision here.