High spatio-temporal variability characterizes micropollutants discharged from separate and combined sewers. This challenges monitoring and prediction. We propose passive samplers (Chemcatcher_® for polar, organic substances) as an alternative to active water sampling. Our results indicate sufficient sensitivity of passive samplers for short exposures so that typical rain event durations (<30 h) can be sampled integratively. Although time-weighted average concentrations estimated via passive sampling are higherthan in composite water samples -on average by a factor 2.7 - we conclude that passive sampling is a cost-effective approach to identify locations with critical concentration ranges.