ALBERT

Description: Effects of discharges from municipal wastewater treatment plants (WWTPs) on degradation of aquatic ecosystems health in European rivers have been noticeably decreased by implementing the EU Urban Waste Water Treatment Directive. Nonetheless, due to targeting end-of-pipe treatments, the Directive does not perfectly guarantee desirable conditions for healthy aquatic ecosystems in receiving rivers. The limitation frustrates attempts to accomplish the aim of the EU Water Framework Directive toward at least “Good ecological status or potential” for all European water bodies by 2027. Over next decades, global challenges such as population change, urbanization, and global warming can more control the dynamics of river ecological risks induced by WWTP-discharges. In line with the spirit of the EU Zero Pollution Vision for 2050, this study aims to suggest and evaluate adaptive approaches regarding the improvement of WWTPs’ treatment technology, the reallocation of WWTP-effluents, and the control of sources at household level, under projected climate change and socio-economic conditions. We employ the dataset for river networks and WWTPs over Europe, the projected total population and urbanization level, and the streamflow simulated by a mesoscale hydrologic model under distinct climate change scenarios. We identify ecological risks via three proxy indicators: the local-scale concentrations of each total phosphorous, ammonium-nitrogen, and diclofenac discharged from WWTPs. Our results inform which technical and/or non-technical adaptation measures are more viable until the legally binding deadlines to prevent river water pollution induced by WWTP-discharges, under the expected future changes.