Impact of membrane configuration on the performance and cost of a pilot-scale UF process treating surface water

•The study compares the performance of outside-in and inside-out UF membrane configuration in a pilot-scale system treating surface water.•One of the tested UF modules has multi-bore inside-out type membranes (M1), and the other has reinforced hollow fiber outside-in type membranes (M2)•Although the treatment performances were quite similar, the filtration performances of the M1 and M2 were different.•This study comparatively presented the long-term operating performance, capital and operational costs for multi-bore inside-out and reinforced outside-in UF membrane configuration.