Influence of urban forms on long-duration urban flooding: Laboratory experiments and computational analysis

Abstract

Water-sensitive urban design is an integral part of flood risk management. Based on computational modelling, we investigated the influence of various urban forms on flooding severity at the level of an urban block and for the case of long-duration urban flooding. The upstream flow depths, downstream discharge partition and flow exchange through the urban forms were examined. The results indicate that one urban characteristic has an overwhelming influence on the flow variables: the conveyance porosity in the main flow direction is by far more influential than the conveyance porosity in the normal direction or the number of streets. Such anisotropic effect was not pointed in recent similar studies, and it hints at practical guidelines for sustainable urban planning in practice. Moreover, the computational model was verified against laboratory observations, which constitute a novel valuable dataset for the validation of other urban flooding models.