The Waterford Steam Electric Station , Unit 3 , also known as Waterford 3 , is a nuclear power station located on a 3,000-acre ( 12-km ) up-river from Hahnville , Louisiana , in St. Charles Parish . The Waterford Steam Electric Station , Unit 3 , also known as Waterford 3 , is a nuclear power plant located on a 3,000-acre ( 12-km Â ) plot in Killona , Louisiana , in St. Charles Parish .