Using historical documents for landslide, debris flow and stream flood prevention. Applications in Northern Italy

Landslides, debris flows and stream floods are common natural processes in Northern Italy. Their occurrence can be correctly assessed in space and time only through a sound basis of knowledge acquired by the scientific use of a large number of historical documents. Over the last 30 years, the CNR IRPI Institute of Turin has made archive data utilisation one of its main points of scientific research, through the collection of hundreds of thousands of records contained in published and unpublished documents and historical reports on natural damaging events over the last 500 years, particularly since XIX Century. The historical data, interpreted and selected on a scientific basis, have been organised in a database and utilised for landscape planning and hydrogeological prevention. In co-operation with public organisations, the IRPI Institute has supplied information (type, location, magnitude, frequency and effects) about hazardous events in Northern Italy. In the last 4 years about 4,500 failure events have been detected along the road network of the Turin Province and many debris flow, rockfall, landslide and flood events in the Lombardy Region. These data are reported as points linked to the relevant event-card on technical cartography (scale 1: 10,000 or 1: 25,000), so that they can be immediately utilised either on paper or digitally (e.g., GIS, Arcview software). The present day elaboration of archival data permit the possible analytical applications for structural interventions in natural hazard remediation in built-up areas. In all cases, the results of research allow public awareness of natural danger and the correct layout of civil protection strategies.