Simulating future trends in urban stormwater quality for changing climate, urban land use and environmental controls Simulation des évolutions futures de la qualité des eaux pluviales urbaines en fonction du changement climatique, de l'urbanisation et des contrôles environnementaux

Effects of climatic changes, progressing urbanization and improved environmental controls on the simulated urban stormwater quality in a Northern Sweden community were studied. Future scenarios accounting for those changes were developed and their effects simulated with the Storm Water Management Model (SWMM). It was observed that the simulated stormwater quality was highly sensitive to the scenarios mimicking progressing urbanization with varying imperviousness and the catchment area. Thus, land use change was identified as one of the most influential factors and in some scenarios, urban growth caused changes in runoff quantity and quality exceeding those caused by a changing climate. Adaptation measures, including the reduction of directly connected impervious surfaces (DCIS) through the integration of more green spaces into the urban landscape, or disconnection of DCIS were effective in reducing runoff volume and pollutant loads. Furthermore pollutant source control measures, including material substitution (e.g., limiting copper content in brake pads) were effective in reducing pollutant loads and significantly improving stormwater quality.