Environmental Quality Standards in the EC-Water Framework Directive: consequences for water pollution control for point sources

The "combined approach" in the new EC-Water Framework Directive(WFD) consisting of environmental quality standards in addition to emission limit values promises improvements in the quality characteristics of surface water. However, the specification of where in the water body the environmental quality standards apply is missing in the WFD. The omission will limit its administrative implementation. A clear mixing zone regulation is needed so that the quality objectives of the WFD are not jeopardized. This need is demonstrated using the examples of point source discharges into rivers and coastal waters, respectively. Furthermore, water authorities will have to make increased use of predictive modeling techniques for the implementation of the "combined appraoch".