 Council Directive 91/271/EEC on Urban Wastewater Treatment was adopted on 21 May 1991, amended by the Commission Directive 98/15/EC.Commission Decision 93/481/EEC defines the information that Member States should provide the Commission on the state of implementation of the Directive.The words "sewage" and "sewer" came from Old French "essouier" "to drain", which came from Latin "exaquāre".