ICM Live - cascading simulations

Efficient hydraulic modelling implies some compromises between :

  • The size of the modelled region
  • The spatial resolution and accuracy of the results
  • The "cost" of these simulations, in terms of computer time and power

In order to maintain a balance between these elements, it can be of interest to setup models working at different scales, that can interact.

Cascading models :

The example below exploits 2 different models :

→ a hydrological model :

Setup at a large scale, it allows the monitoring of the meteorological forecasts in order to detect intense rainfall events and the corresponding outflow, on a set of subcathments (forecast data : ARPEGE Météo France):


Here, the model detects rainfall depth above the fixed threshold in the meteorological forecasts:

alerte hydrologique

 → a hydraulic model :

The alert then triggers a fully hydrodynamic simulation of the subcatchment where the threshold was overtopped, and provides the potential flooded zones, based on more accurante meteorological forecasts (AROME Météo France) :


This article is part of a set that documents the setup of an experimental real time model, the results don't correspond to real crisis management situations.

Note : Surface Libre is independant from Innovyze (editor) and Geomod (french distributor) of the ICM solutions.

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