Analyse und Bewertung von Überflutungen in urbanen Siedlungsgebieten am Beispiel der Modellstudie Bründlbach (Graz-West)

In urbanized areas, even those far from rivers, torrential rains can lead to flooding and produce significant damage. In order to improve flood protection, we must first identify and assess relevant shortcomings and risks in the respective areas. This step will in turn enable us to effectively develop and implement suitable protective measures and improvements at both the municipal and private level. The growing use of 1D-2D models as tools for planning and verification brings with it new challenges concerning the modeling, base data, calibration and validation. The methodology presented here facilitates the recognition and evaluation of shortcomings, as well as the development and deployment of appropriate flood protection measures. In light of the fact that combinations of shortcomings are often responsible for flooding in urban settled areas, employing complex 1D-2D models is advisable; these models can serve both as verification tools and as planning tools for potential flood protection measures. The methodology promotes future-oriented flood protection and demonstrates that the focused application of 1D-2D models in urban areas is called for in order to fulfill municipalities’ joint responsibility for ensuring reliable urban flood protection.