A case study for an integrated real time control (RTC) in the catchment Wohlen-Villmergen, Switzerland is introduced. The RTC-based control was simulated for the inflows to the wastewater treatment plant Wohlen and the connecting sewer system using a conceptual model in CityDrain II. For evaluating the model performance, high-resolution routine data were available for the entire year of 2015. The main goal of this thesis was to control the system with an aim to improve the receiving water quality. In urban drainage systems, combined sewer overflows (CSO) represent the main pollutant source. A load-based approach was introduced to further characterize CSO. Then, different static and dynamic control strategies were compared for reducing CSO number, volume and load. It was found that a dynamically controlled RTC can avoid 25 % of CSO events that would have happened in a static controlled system in 2015. However, the reduction was much smaller for overall CSO volume (7 %) and load (9 %).