Between July 12 and 19, 2021, large parts of Europe were struck by extreme rainfall caused by a quasi-stationary low-pressure system. The floods resulted in severe destruction, caused directly by the hydrodynamic forces of the flowing and ponding water, and further amplified by floating debris, bank erosion, and sediment deposition. In addition to floodplain damage, multiple shallow landslides were triggered along the steep Ahr embankments. The floodwaters also undercut several older landslide bodies. One of these is located near the town of Müsch, where Devonian schist bedrock forms a narrow, curved section of the river valley.
Over the past months, and continuing until the end of this year, the research group by Prof. Lothar Schrott has been closely monitoring the landslide in Müsch in collaboration with several partner institutions, i.e., University of Göttingen/RWTH Aachen and the LGB RLP. Recent data indicate that the landslide has shown renewed activity, raising concerns about further destabilization. The research group contributes a range of datasets, including electrical resistivity tomography (ERT) monitoring, seismic refraction surveys, passive seismic monitoring, hydro-meteorological data, and unmanned aerial vehicle (UAV) surveys. This data is combined with surface and subsurface deformation rates and borehole data from project partners.
The integration of direct borehole, indirect geophysical, geodetic, remote sensing, and hydro-meterological methods provide a better understanding of the driving mechanisms and processes of the Müsch landslide. Based on this multidisciplinary approach we assess the magnitude of the landslide, which could cause a hazard cascade at this site.