Induced by well abstraction, surface water infiltrates into Berlin aquifers and is used for drinking water production. A major advantage of bank filtration is the capability of the subsurface to remove contaminants and save natural groundwater resources. Since a large proportion of the surface water in Berlin originates from treated effluents released by wastewater treatment plants, certain wastewater residues can be traced into the groundwater. A powerful tool to characterise bank filtration systems is the use of wastewater indicators and additional environmental tracers to estimate flow velocities and proportions of bank filtrate in the abstraction wells prior to reactive transport evaluations. Examples for tracer applications at the Berlin system are introduced in this paper. In addition, an overview on results of various studies conducted on contaminant transport and removal during underground passage of the bank filtrate in Berlin is given.