Résumé
The French Cevennes-Vivarais region, located in the South-East of France, is frequently hit by intense meteorological events, leading to flash-floods that can be very destructive. Social analyses of damages caused by past events showed that the risk level for people is dependent on the hydrological scale. In particular, Ruin et al. (2008) pointed out a maximal risk level for people facing flash floods occurring in catchments with a size smaller than 20 km². In this context, distributed physically-based models appear to be usefull tools to test hypothesis on runoff generation governing processes, at scales where streams are intermittent and catchments ungauged. This work focuses on pre-event soil moisture state, which is known to be a major flood explanatory factor, necessary to be taken into account by hydrological models.