Reducing the complexity of the flood vulnerability index

The current flood vulnerability index (FVI) methodology developed by the authors uses 71 indicators in its calculation. However, it is recognized that some of these indicators may be redundant or have no influence on the results. This paper presents the results of analysis carried out to select the most significant indicators in order to establish parsimonious usage of the FVI. As with the original methodology, this is applicable at three different spatial scales (river basin, sub-catchment and urban) and to the various components of flood vulnerability (social, economic, environmental and physical). For the FVI methodology to be sustainable, improvements were made by analysing the indicators' relevance and by studying the main indicators needed to portray reality of the fluvial floods in an effective way. For this purpose, mathematical tools (a derivative and a correlation method) and expert knowledge (via a questionnaire) were used. Finally, all these methods were combined in order to select the most significant indicators and to simplify the FVI equations. After reducing its complexity, the FVI can be more easily used as a tool for education, improvement of decision making and ultimately reduction of flood risk.