Using Historical Documents for Landslide, Debris Flow and Stream Flood Prevention.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 inNorthern Italy. Their occurrence can be correctly assessed in space and timeonly through a sound basis of knowledge acquired by the scientific use of alarge number of historical documents. Over the last 30 years, the CNR IRPIInstitute of Turin has made archive data utilisation one of its main points ofscientific research, through the collection of hundreds of thousands of recordscontained in published and unpublished documents and historical reports onnatural damaging events over the last 500 years, particularly since XIX Century.The historical data, interpreted and selected on a scientific basis, have beenorganised in a database and utilised for landscape planning and hydrogeologicalprevention. In co-operation with public organisations, the IRPI Institute hassupplied information (type, location, magnitude, frequency and effects) abouthazardous events in Northern Italy. To give an example, in the last 4 yearsabout 4,500 failure events have been detected along the road network of theTurin Province and many debris flow, rockfall, landslide and flood events inthe Lombardy Region. These data are reported as points linked to the relevantevent-card on technical cartography (scale 1:10,000 or 1:25,000), so that theycan 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.