Developing a GIS tool to assess potential damage of future floods

The evaluation of potential damage of future floods is an essential part of flood management project appraisals. Analysis results reliability is an important issue when comparing flood risk reduction project scenarios. Geographic Information System (GIS) technology plays a crucial role on flood risk analyses. On one hand, the evaluation process requires data on flood hazard and on vulnerability of assets at risk, both spatial data. On the other hand, this data must be combined in order to evaluate flood risk. Even though the role of GIS is central in the evaluation process, GIS software does not offer specific tools for achieving flood damage analysis. The use of standard methods for assessing and combining different data influences accuracy and comparability of evaluation results. Few countries in the world have developed national standard methods to assess flood damage potential. The construction of GIS-based methodologies and GIS models can be the first step toward standardisation of the whole evaluation process. In this purpose, this article presents the development of a GIS tool for evaluating future flood damage potential: F.R.A. GIS tool extension, for use with ArcGIS (ESRI). It first explains how GIS technology is used in flood risk analysis procedures. Then, the tool preand post-functions as well as structure of the model are detailed. Finally, a brief case study is presented in order to illustrate the functionalities of the model developed in this article. The methodology described here can be used to guide analysts on the realisation or the automation of flood risk analysis using other GIS software.