Alluvial fans are often present at the outlet of\udsmall drainage basins in alpine valleys; their formation is\uddue to sediment transport associated with flash floods and\uddebris flows. Alluvial fans are preferred sites for human settlements\udand are frequently crossed by transport routes. In\udorder to reduce the risk for economic activities located on or\udnear the fan and prevent loss of lives due to floods and debris\udflows, torrent control works have been extensively carried\udout on many alpine alluvial fans. Hazard management\udon alluvial fans in alpine regions is dependent upon reliable\udprocedures to evaluate variations in the frequency and severity\udof hydrogeomorphic processes and the long-term performance\udof the torrent training works. An integrated approach\udto the analysis of hydrogeomorphic processes and their interactions\udwith torrent control works has been applied to a large\udalluvial fan in the southern Carnic Alps (northeastern Italy).\udStudy methods encompass field observations, interpretation\udof aerial photographs, analysis of historical documents, and\udnumerical modelling of debris flows. The overall performance\udof control works implemented in the early decades of\ud20th century was satisfactory, and a reduction of hazardous\udevents was recognised from features observed in the field and\udin aerial photographs, as well as from the analysis of historical\udrecords. The 2-D simulation of debris flows confirms\udthese findings, indicating that debris flow deposition would\udnot affect urban areas or main roads, even in the case of a\udhigh-magnitude event. Present issues in the management of\udthe studied alluvial fan are representative of situations frequently\udfound in the European Alps and deal with the need\udfor maintenance of the control structures and the pressures\udfor land use changes aimed at the economic exploitation of\udthe fan surface.
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