Validation of urban surface water flood modeling with multisource data: Two case studies in Baoji and Linyi cities, China

The focus of this study is on city-scale flood inundation model validation using multisource data. A raster-based 2D hydrodynamic model is used for simulating urban surface water floods, then the model is validated with city-scale multisource data in two case studies, Baoji City and Linyi City, China. A large number of urban surface water flood models have been developed to derive flood inundations and support risk management.

However, unlike fluvial and coastal flooding, urban pluvial flooding is often associated with shallow water and thus the model is difficult to validate with traditional monitoring data. In this study, a full two-dimensional (2D) hydrodynamic model was developed for simulating surface water floods. The model's performance is further evaluated with multisource data from flood incidents, including official reports and social media data. The results demonstrate that the model is able to derive the broad patterns of flood inundation at the city scale. The approach tested could be applied to other flood-prone cities and future research could include water depth information for more robust model validation.