Conference Agenda

The Digital Twin platform developed for the “ZwillE” research project in Germany serves different purposes, covering a wide range of urban water management tasks of the wastewater utility of Hannover in Germany. Fundamental concepts, such as model integration issues and different use cases with different levels of complexity are tackled within the project. This contribution focuses on a new approach for the fast estimation of maximum water levels for use in relatively flat urban environments. The approach combines pre-calculated flood maps based on design rainfall for fixed return periods with online radar measurements and radar nowcasts, including uncertainty information. As case study, a convective heavy rainfall event in Hannover is evaluated with observed flooding and a high number of fire brigade calls registered. Results of the new approach for fast flooding estimation are evaluated in comparison to fire brigade calls and to a coupled 1D sewer and 2D surface runoff simulation using the model Hystem-Extran/Hystem-Extran2D. The fast estimation shows good results of the maximum water level in comparison to the reference simulation, with absolute differences mostly below 0.1 m or 0.2 m respectively. The approach is suitable for real-time application in the newly developed digital Twin for the city Hannover.