Simulation of flooding and flood mitigation in the town of Söderköping using HEC-RAS : An investigation of floods and mitigation measures

Abstract: This study examines the effects of flood management systems in an HEC-RAS simulation of recorded discharge in the town of Söderköping in Sweden by using easy-to-access and publicly available hydrological, landcover, and soil data. Two rivers and the precipitation of a chosen area are studied. A MATLAB calculation is used to generate the return period of the worst-case flood recorded. By analyzing these scenarios, bottlenecks are easily identified. The second part of the study entails a simulation of flood management systems with the above scenarios, which is also conducted in HEC-RAS. The results show that this can be a method of choice and can be used to estimate where to establish resources for flood management and to obtain a rough idea of how structures should be built to prevent flood damage. The data used are easy-to-access data from The Swedish Meteorological and Hydrological Institute (SMHI) and Lantmäteriet.