Vulnerability of Slovak municipalities to fluvial flooding

Abstract

In this study, we aim to analyze the vulnerability of municipalities in Slovakia to fluvial floods. A fluvial flood vulnerability index (FFVI) related to the year 2021 was calculated for 2927 municipalities using spatial multi-criteria analysis and geographic information systems (GIS). We chose eleven indicators representing the economic and social vulnerability: number of buildings in 100 m distance from a watercourse; length of roads in 100 m distance from a watercourse; number of bridges over a watercourse; population density of municipalities; share of residents aged 65+ from total number of residents; share of unemployed residents from total number of economically active residents; share of the Roma ethnicity from total number of residents; share of households with six and more persons from total number of households; share of incomplete households from total number of households; share of residents without education and with primary education from the total number of residents; and share of disabled residents from total number of residents. We normalized the original values of indicators and determined the importance of indicators via the Pearson correlation between individual indicators and the number of flood events in a municipality. To calculate the normalized weights of indicators, we used the rank sum weighting method. The FFVI was determined as an aggregation of weighted indicators. Moreover, we determined the spatial clusters of municipalities with respect to their vulnerability to fluvial floods using the local Moran's coefficient of spatial autocorrelation. This work was supported by the VEGA agency under the grant number 1/0103/22.