A new Approach to Hazard Analysis of Heavy Rainfall Events based on the Catchment Area of the Ahr River

Abstract

In the summer of 2021, heavy rainfall over North Rhine-Westphalia and Rhineland-Palatinate led to catastrophic flooding, especially in the Ahr valley. This study presents the results of a method calculating the extent of a possible flood with a small amount of input data. The results are finally compared with aerial photographs and a flood line reconstructed from them. The method was developed to be as transferable as possible - especially to regions with insufficient data for detailed modelling and compared with the reference data of this flood event as an example.