Integrating hydrodynamic and hydraulic modeling for evaluating future flood mitigation in urban environments

Abstract

We present an integrated flood modelling tool that is able to evaluate different mitigation solutions for areas that are prone to floods from storm surge and heavy rainfall. Our model integrates catchment and coastal flood modelling (spatio-temporally dynamic), including sea level rise, to provide a holistic inundation model for future flooding. Additionally, the model aims to enable simulation of a combination of flood mitigation and adaptation options. To date, the practice has been to model either drainage augmentation solutions alone, or (for coastal inundation) single coastal adaptation solutions. This tool aims to deliver the capacity to model a range of both coastal and drainage adaptation solutions to understand what combination of solutions might be effective. The model is demonstrated for example cases in the City of Port Phillip, Melbourne. Three mitigation strategies involving the use of a hypothetical off-shore reef and the combination of a single valve systems and retention/detention measures are evaluated for the region around Elwood canal for current and future scenarios.