First methodological ideas on how to proceed with the cost-effectiveness analysis under the EU Water Framework Directive have already been developed by a number of European Member States. Yet, important methodological challenges remain, in particular with regard to a scale adapted procedure. This paper takes up the current debate and develops ideas on how to address the problem of interlinking bottom-up and top-down approaches for the selection of cost-effective sets of measures under the Directive.

The European Water Framework Directive (WFD) will prompt far-reaching changes and a fundamental reorientation of EU water management. This includes the attainment of specified environmental targets for all water bodies by 2015, whereby ecological aspects in particular, as well as economic considerations, must be taken into account in all decision-making processes affecting water management. One of the most demanding tasks is the selection of cost-effective measures to tackle various pressures on EU waters, according to Article 11 of the Directive.