Supreme Court rejects state’s claim of ownership of groundwater, extends equitable apportionment doctrine to disputed Memphis aquifer

The U.S. Supreme Court has rejected Mississippi’s claims of state ownership of groundwater within its territorial boundaries. Mississippi v. Tennessee, 595 U.S. 15 (2021). Chief Justice Roberts authored a unanimous opinion for the Court. The Court rejected state ownership of groundwater and instead, as a matter of first impression, extended the equitable apportionment doctrine for flowing waters and resources to the disputed Memphis aquifer. Over two decades of litigation in federal courts, Mississippi has pressed... Read more →