Flood early warning with 3Di in a 3D Digital Twin
As a disruptive new force within water management and spatial planning, digital twins act as a means of accounting for the impacts of design choices in the public domain. This is accomplished through the careful digital modeling of physical objects such as buildings, bridges, and roads or systems and processes like the hydrodynamics of floods.
Nelen & Schuurmans, Virtual City Systems, and the district of Hof are currently developing a digital twin that is capable of simulating an emerging flood and its impact on buildings and infrastructure such as roads, bridges, and electricity. The digital twin is created for the city of Selbitz and Köditz. Both cities were hit hard by the recent storms on the 12th of July. According to the Deutscher Wetterdienst, more than 80l of rain fell within 12 hours in the regions. In the entire district the torrential rain led to floods that got people injured, roads closed, cellars and buildings flooded and power outages occurred.
The development of this digital twin is part of the Smart Cities project funded by the Federal Ministry of the Interior, Building, and Community and KfW. The digital twin will strengthen the municipalities’ ability to act and become more resilient against the types of floods that occurred on the 12th of July.
To focus on the hydrodynamic part of the project: the challenge is to create a representation of reality with sufficient detail but also quick enough in cases of calamity events. To do so the elevation dataset is edited to incorporate the obstacles in the terrain model such as the footprint of buildings, bridges, culverts and also the riverbed.
In this project the 3Di calculation results are live shown in a 3D Digital Twin. This is possible thanks to the 3Di API which covers all functionality of the computational core, including live results.
The rainfall input for the model comes from the precipitation forecasts of the ICON D2 weather model and can be used if the user is interested in the impact of upcoming weather events. The user can also simulate historical events using the radar observed rainfall data of RADOLAN. These types of model runs can be used to investigate how the water system reacted and what measures or design choices in the public domain could help mitigate the impact of floods in the future.
The 3Di-API allows for the full integration of a hydrodynamic model within VC View and lets the user start a hydrodynamic simulation using either a precipitation forecast or historical radar data directly from their 3D City Twin.All cases