The U.S. Supreme Court unanimously upheld states’ authority to regulate hydroelectric dams under the Clean Water Act. In a 9-0 opinion issued May 15, the court turned back a challenge by S.D. Warren Co. to a Maine agency’s regulation ofdischarges from the company’s stringof hydroelectric dams along the Penobscot River. Writing for the majority, Associate Justice David Souter said “changes in the river [affecting fish habitat} fall within a state’s legitimate legislative business and the Clean Water Act provides for a system that respects the states’ concerns.”