Berlin’s drinking water is produced from groundwater replenished by 60 % from surface water from the city’s abundant rivers or lakes using bank fi ltration or artifi cial groundwater recharge. Compared to other bank fi ltration sites world wide, the situation in Berlin is characterized by low hydraulic conductivities but nevertheless high capacities. Interdisciplinary research projects have shown that travel times and redox conditions during subsurface passage are highly transient due to seasonal effects and discontinuous pump operation. Trace organics like pharmaceuticals and x-ray contrast media are attenuated during subsurface passage to a varying degree. Substances that were found to be poorly removed under oxic conditions or even persistent include carbamazepine, primidone, sulfamethoxazole, 1,5 NDSA, MTBE and EDTA. Under anoxic to anaerobic conditions others like phenazone and diclofenac show little removal. However, none of these substances occur at relevant concentrations in the fi nished drinking water due to low initial concentrations in the surface water or additional removal during post-treatment (aeration and fi ltration for iron and manganese removal).