What is Delft-FIAT?

Delft-FIAT is a free, python-based Fast Impact Assessment Tool, designed and continuously improved by Deltares. It is configured to run quick, consistent, and well-founded flood damage and risk calculations on the basis of flood maps and additional inputs such as depth-damage functions, asset locations, and their maximum potential damages. Delft-FIAT allows rapid assessment of the direct economic and monetary impacts to buildings, utilities, and roads for specified flood events and return periods. Fast impact modeling removes bottlenecks in climate adaptation planning, allowing for large numbers of calculations needed to understand the effectiveness of adaptation strategies and the changes in damage and risk as climate and socio-economic conditions change. In the further documentation, Delft-FIAT will be refered to simply as FIAT.

FIAT works with an easy format for exposed assets, consisting of information on the location, exposed value, ground floor height, and associated depth-damage functions, which can be modified by the user. A simple configuration file specifies the location of depth-damage functions and flood maps, as well as return periods of flood maps if calculating risk.

Thanks to its flexible character, FIAT integrates with various software applications such as flood adaptation planning tool FloodAdapt or an interTwin digital twin and can be called multiple times to e.g. assess uncertainty in damage estimates, or run for numerous flood scenarios.

	Field	Description
1	Flood maps	Hazard input: Selected per damage/risk simulation
2	Damage functions	Vulnerability input: Prepared when setting up the model, coupled to exposure objects
3	Exposure data	Exposure input: Prepared when setting up the model, including exposure assets and max potential damages
4	Delft-FIAT	Flood Impact Assesment Tool
5	Flood impact	Resulting (economic) damages and risk