10.4122/1.1000001601 Uhl, M. Dittmer, U. Fuchs, S. Soil filters for enhanced treatment of CSO - Recommendations and developments in Germany DTU Library, Technical University of Denmark (DTU) 2005 Advanced treatment combined sewer overflow construction dimensioning operation vertical flow soil filters University of Applied Sciences of Muenster, Laboratory of Water Resources Management Technical University of Kaiserslautern, Institute of Environmental Engineering University Karlsruhe, Institute of Aquatic Environmental Engineering en Conference presentation 10.4122/1.1000001602 text/xml 1 Vertical flow sand filters have been developed as powerful tools for treatment of combined sewage overflow. Essentials of two technical guidelines (MUNLV (2003), DWA M 178 (2005)) are described which were recently worked out in Germany with significant contributions by the authors of this paper. The recommended layout comprises a retention basin on top of a sand filter layer (grain size 0/2 mm). The filter velocity is controlled by a throttle in the outflow. For COD, NH4-N and SS medians of removal rates typically range between 70-90 % can be expected under regular loading conditions. However, extreme conditions such as exceeding loads of SS, frequent loading and long-term inundation have adverse effects on the performance of the filter plants. Recommendations for successful long term operation were derived from various field studies.