A Novel River-Basin Approach for Regional Flood Risk Management (Regio-Fem)

Due to the fact that floods, among all natural disasters, have one of the greatest damage potential worldwide and that their occurrence has increased since the beginning of the new millennium, flood risk management is of high importance. In particular, floodplain conservation and restoration are key aspects of flood risk management which are identified and defined in the EU Floods Directive. Catchment-oriented and regional flood management approaches are very effective for a sustainable flood risk management. Therefore, a river-basin approach called Regional Floodplain Evaluation Matrix (Regio-FEM) was developed with the target to gain policy-relevant insights and conclusions for a regional floodplain and flood risk management. Regio-FEM combines spatial (e.g. affected buildings), hydrological (e.g. peak reduction), hydraulic (e.g. water level change) as well as monetary parameters (e.g. potential damage) and allows an integrated assessment of the importance of floodplains in a catchment or river reach. In addition, the interdisciplinary evaluated parameters allow a prioritization of scenarios and therefore serve as a supportive tool to decision makers in flood risk management. In this study, the results of the Regio-FEM for a case study at the river Raab in Austria are presented. The results demonstrate that the method is suitable for assessing regional effects of land use and climate change-related consequences as well as for estimating and communicating the effects of planned flood protection measures on flood risk development in a river reach or catchment.