The project AVOSS "Impact-based forecasting of heavy rain and flash floods at different scales: potentials, uncertainties and limitations" investigates the process chain of flash floods starting from meteorology via hydrology and hydraulics up to damage and risk assessment. The aim of the project is to further develop the common hazard-based heavy rainfall forecasting (focus on precipitation) to an impact-based flash flood forecasting (focus on runoff events and resulting impairments). The results of AVOSS will help improve early warning and heavy rainfall management in selected pilot communities. The interdisciplinary project is coordinated by the University of Freiburg and conducted by project partners from science (Leibniz University Hannover, German Research Centre for Geosciences GFZ, Forschungszentrum Jülich) and practice (AtmoScience GmbH, BIT Ingenieure AG, HYDRON GmbH). Beside the pilot communities, further practitioners (e.g. responsible authorities, engineering consultancies) are actively involved in the project.

The GFZ Hydrology Section is responsible for work package D: "Damage model, damage-based forecasting and risk communication". In a first step, a multivariable, probabilistic damage model for flash floods will be developed and validated. Based on results from the other work packages, this damage model will then be used to develop risk maps for flash floods, which can be used for heavy rainfall management in the pilot communities. In addition, a model chain for (near) real-time damage-based forecasting will be implemented in collaboration with the project partners, allowing for rapid identification of damage hotspots during a flash flood. Finally, the communication potential of the developed risk maps and damage-based forecasting will be evaluated and compared in a user workshop with associated practitioners.