Riverine flood potential assessment at municipal level in Slovakia

Study region: Slovakia – 2927 municipalities. Study focus: This study maps and assesses the riverine flood potential in municipalities of Slovakia using the vector-based spatial multi-criteria analysis and geographic information systems (GIS). The flood potential index (FPI) in municipalities was computed based on eight flood factors, which were normalized, weighted and aggregated into the FPI index. Furthermore, we analyzed the spatial clusters of riverine flood potential using the local Moran’s coefficient of spatial autocorrelation. New hydrological insights for the region: The very high and high FPI (767 municipalities) was recorded mostly in municipalities of northern and eastern Slovakia. Very low and low FPI (1452 municipalities) dominates in western and southern Slovakia while moderate FPI (708 municipalities) was mainly recorded in municipalities of central Slovakia. The number of statistically significant high-high and low-low spatial clusters of riverine flood potential was 16 (524 municipalities) and 18 (487 municipalities), respectively. Clusters of positive spatial autocorrelation are mostly located in the northern and eastern Slovakia, one cluster in western Slovakia and seven clusters in central Slovakia. Clusters of negative spatial autocorrelation are mostly located in western and southern Slovakia and three clusters in eastern Slovakia. The proposed methodology can be useful for regular updating of Preliminary Flood Risk Assessment (PFRA) in Slovakia under the EU Floods Directive.