For many power plants, 2004 will be a record year for regulatory scrutiny. First came the Interstate Air Quality rules, and on the horizon next March are new mercury regulations. At the other end of the plant, amended once-through cooling regulations have made compliance with the Clean Water Act even more uncertain. Confused? You're not alone. But take heart. This article unscrambles the new Clean Water Act Phase 11 rules and reviews some of the technologies capable of meeting them.