Delft-FIAT

The Delft-Flood Impact Assessment Tool is a flexible Open Source toolset for building and running flood impact models that are based on the unit-loss method. The input needed for a flood impact assessment are exposure maps (i.e. where are the houses and the people), impact functions and maximum damages, all related through a model configuration file, either in Excel or JSON format.

To apply FIAT in a Delft-FEWS workflow, you will need an inundation grid series (e.g. satellite image or flood inundation model like Delft-FM or 3Di-subgrid) to hand over to FIAT. When providing a max-depth map to FIAT it can calcualte the (financial) damage per category on the map or as a total value for the entire area . This max-depth map needs to be prepared in FEWS as a grid series with one timestep. When you also provide a flood wave (grid series with multiple timestep) to FIAT, it can compute the human impact (mortality and casualties) by internal conversion of the wave into (vertical) rise rate and an arrival time map. This conversion may take some time (several minutes).

FIAT-adapter

The FIAT-adapter (fews_wrapper.py) is wrapped around the FIAT computational core and available in the FIAT distribution. To accommodate portability without python installation troubles, a self-contained executable is available on request with Edwin Bos at Deltares.

The integration of FIAT in a Delft-FEWS workflow is established by direct support of the Delft-FEWS formats (pi_run.xsd, NetCDF-CF and pi_diag.xsd) in combination with the JSON model configuration file of FIAT.

The pi-run file

The pi-run file specifies where the max_depth.nc, floodwave.nc (optional)

The max_depth.nc (input) file

This file is a standard NetCDF-CF grid with one timestamp. The variable name to be used is

The floodwave.nc (input) file

The JSON file

The impact_on_grid.nc (output) file

The impact_summary.nc (output) file