COMBINED SEWER OVERFLOW FROM THE CITY AREA OF MUNICH

A joint research project is being carried Out between the Department of Drainage of the City of Munich and the Institute of Water Quality and Waste Disposal of the Technical University of Munich. In the next few years the Department of Drainage intends to take measures to reduce the impact of combined sewage overflows on the receiving waters of the Isar River. The expected effects of planned measures will be investigated by means of a computer simulation. To verify the results of independent computer simulations concerning the pollution load of overflow events into the river, an ongoing field study is being carried out at three overflows of the sewerage system in the city area of Munich. The purpose of the study is to investigate the quantity and quality of combined sewer overflows into the receiving waters of the Isar River. The major research aims of this investigation are to find out the duration, frequency and volume of combined sewer overflows and to determine the concentration of the parameters COD, BOD5 and settlable solids and the pH value. For some overflow events the heavy-metal load of lead, copper, zinc and cadmium was also examined. The different performance of three catchment areas contributing to the overflows is shown, together with the monitoring equipment and first results of this study.