Urban diffuse pollution: key data information approaches for the Water Framework Directive

The Water Framework Directive (WFD) provides a coherent structure within which the problems of diffuse urban pollution can be effectively tackled and managed. The context of impermeable surface water quality within the terms of the Directive are outlined, and the pollutant sources and loadings associated with various urban land uses are identified. Stormwater flows and quality are sufficient to prejudice any ‘good’ ecological potential, particularly in terms of chronic receiving water sediment toxicity. A simple volume–concentration method for the prediction of pollutant loadings and impact assessment on a subcatchment scale is described and discussed.