In assessing a flood event two risk components need to be considered: the intrinsic hazard of the hydrome- teorological event causing the flood and the vulnerability of the area where the precipitation has been registered. In the present study four flood events selected by the FLASH Eu- ropean project have been classified according to the charac- teristics of the meteorological event (classification according to hazard) and according to the physical and economic dam- ages caused (classification according to vulnerability). The social impact of these events is analysed taking into account the growth of the population. An increase in the number of extraordinary flash-floods was detected in the areas with a major growth of the population, as a consequence of an in- creased vulnerability of these areas, both from a physical per- spective (exposure of infrastructures) and from an economic perspective (more goods exposed). In addition, the numer- ous non-native inhabitants of the region are not aware of the meteorological risks characteristic of the area, and this con- tributes to increased social vulnerability