Witnesses testified about the effect of the U.S. Supreme Court's recent decision in the joint cases of Rapanos v. United States and Carabell v. U.S. Army Corps of Engineers on the scope of the federal government's power to regulate wetlands through the Clean Water Act of 1972. Topics included the definition of 'navigable waters,' the roles of the Environmental Protection Agency and the Army Corps of Engineers, jurisdictional disputes, measuring water quality, and the specific assents and dissents in the U.S. Supreme Court decisions.