The effect of oscillating pumping regimes at the bank filtration site in Berlin Tegel is examined via a scenario based modelling study. There are several scenarios for the pumping regimes, some adopted from the operation of the plant by the Berlin Water Works (BWB), some hypothetical with a regular oscillating regime. A horizontal 2D model of the lower aquifer is set-up, in which the third type boundary condition is used to mimic the influence of an irregularly shaped till layer, overlying the main aquifer. Model results in form of flowpaths are presented for several pumping scenarios. They reveal that there is a substantial influence of the pumping regime on the flowpaths in the vicinity of the well gallery, while in the farfield, including the bank of the surface water body (here: Lake Tegel) the oscillating effect is rather small. It depends very much on the infiltration position on the bank, whether traveltime through the aquifer changes as effect of irregular pumping.
Assessment of bank filtration pumping regimes on flow length and travel times: a case study