Landslide hazard and risk assessment on the Scottish road network Available to Purchase

A series of rainfall-induced debris flow events in August 2004 affected the Scottish road network, and at Glen Ogle 57 people were airlifted to safety. Although there were no major injuries, the social and economic impacts were significant, particularly the severance of access to and from relatively remote communities. A study was commissioned with the overall purpose of ensuring that the hazards posed by debris flows were systematically assessed and ranked, thus allowing actions at specific sites to be prioritised effectively within available budgets. The methodology used to undertake a pan-Scotland, GIS-based assessment of debris flow susceptibility is described, as is the approach taken to interpret the resulting imagery in order to establish those sections of road alignment subject to hazards. The hazard scores assigned using this approach were subsequently modified in the light of the results of site-specific inspections. The ranking of hazards based upon the potential exposure of road users to debris flow hazards and the potential socio-economic impacts is also described, and a map illustrates the locations of the highest hazard-ranking sites. The success of the system is briefly discussed in the context of subsequent events, and the approach to management and mitigation is outlined.