High resolution modelling and analysis of urban flooding

Abstract: The predictions on climate change and precipitation patterns in the near future, as well as urbanization, lead to higher volumes of runoff, which in turn challenge the sustainability and functionality of urban drainage pipe networks. In order to understand how these changes will affect the existing infrastructure in urban areas, integrated urban water model software are needed to identify effective solutions to minimize urban flooding. The aim of this thesis is to test and examine a newly developed, vector-based, high resolution software model, the Tokyo Storm Runoff (TSR) model in the small urban catchment of Augustenborg located in the southern part of Malmö, Sweden. It was found that the TSR model demonstrated the capability to simulate high resolution urban flooding and highlight, in extreme detail, areas of the catchment that are more vulnerable to flooding. Precipitation appeared to infiltrate permeable areas until infiltration capacity is reached and excess runoff is observed to flow with respect to Digital Elevation Model (DEM). Due to lack of observed data, no calibration or tuning was performed but standard parameter values from previous studies were used. Although the potential underestimation of inundation depth remains a limitation of this study, the model was able to determine relative performance of drainage outlets within the catchment. It is concluded that TSR software model represents a reliable, effective, and fully customizable tool in terms of urban flood analysis based on comparison of the simulation results between TSR and MIKE Urban and the similarities that both have in common. Despite the TSR model’s minimal requirements for input data, it requires excessive manual effort and therefore a further code development is recommended. This thesis is a part of the research project FloodView coordinated at the Department of Water Resources Engineering, Lund University. FloodView is an international research project aiming to provide a web-based flood control decision support system for various stakeholders, such as municipality managers/decision makers to identify effective solutions to minimize urban flooding.