Integrated Control in Copenhagen

Pollution from combined sewer overflow poses a threat to the environment and to healthy bathing waters. This paper describes Copenhagen's efforts to optimize the utilization of the city's wastewater infrastructure through the implementation integrated real time control using radar based flow forecasts and a risk based optimization strategy. Described are some of the practical challenges that have been met and how they have been tackled.Setting up the global integrated control system has involved the development of new control modules, linking SCADA systems across organizations and incorporating new data sources into the closed-loop controls such as weather radar forecasts. The implementation project has been closely linked to R&D activities such as the Storm and Wastewater Informatics project involving academic institutions, consultants and wastewater utilities. Many lessons have been learned in transferring theoretical opportunities to automated controls in the real world.The early warning of high flows provided by the radar based flow forecast has already allowed the largest wastewater treatment plant (WWTP) to reduce bypass pollution loads by about one third. The projects next phase is focused on incorporating the city's largest sewer pumping station into the global control and is expected to reduce overflow occurrences from the current more than 80 a year to less than 15 per year without compromising the bathing water objectives of the inner harbor.