Water events and historical flood recurrences in the Vietri sul Mare coastal area (Costiera Amalfitana, southern Italy).

This study addresses problems pertinent to the municipality of Vietri sul Mare located in the southeastern corner of the Amalfi coast (southern Italy). The physical landscape, the economic settlements, the social activity and the natural hazards characterizing this area depend particularly on water: meteoric, riverine and marine. Indeed Vietri sul Mare is located on a steep rocky coast deeply dissected by ephemeral water courses (the Stream Bonea basin) with human activities mainly developed on the narrow stream banks located at the base of steep sided valleys, or at the mouth of Stream Bonea. This exposes them to a high hydrogeological risk triggered by water events associated with heavy rain. Several historical sources report at least 22 flooding events for the Vietri area during the last three centuries, which caused severe damage. In this paper historical sources are combined with geological data in order to improve the mitigation of flood phenomena through the reconstruction of historical floods and the estimation of the associated risks.