Landscape analysis for multi-hazard prevention in Orco and Soana valleys, Northwest Italy

Abstract

The study area (600 km2), consisting of Orco and Soana valleys in the Western Italian Alps, experienced different types of natural hazards, typical of the whole Alpine environment. Some of the authors have been requested to draw a civil protection plan for such mountainous regions. This offered the special opportunity (1) to draw a lot of unpublished historical data, dating back several centuries mostly concerning natural hazard processes and related damages, (2) to develop original detailed geo-morphological studies in a region still poorly known, (3) to prepare detailed thematic maps illustrating landscape components related to natural conditions and hazards, (4) to thoroughly check present-day situations in the area compared to the effects of past events and (5) to find adequate natural hazard scenarios for all sites exposed to risk. The method of work has been essentially to compare archival findings with field evidence in order to assess natural hazard processes, their occurrence and magnitude, and to arrange all such elements in a database for GIS-supported thematic maps. Several types of natural hazards, such as landslides, rockfalls, debris flows, stream floods and snow avalanches cause huge damage to lives and properties (housings, roads, tourist sites). We aim to obtain newly acquired knowledge in this large, still poorly understood area as well as develop easy-to-interpret products such as natural risk maps.