A Comparative Analysis of Avalanche Risk Assessment for Local Mountain Roads

For avalanche risk management, local authorities need streamlined and quantitative approaches to define the risk of exposed elements. In this paper, two quantitative avalanche risk assessment approaches are compared: (1) Wilhelm’s method, referring exclusively to transport routes, defines numerically the risk, and (2) the multi-criteria risk assessment (McRA) (Italian avalanche risk guidelines), which defines the risk through categorical results. It provides a degree of avalanche risk to which the element is exposed, according to the definition of a risk class (RC). This method allows a simplified avalanche risk analysis for different types of buildings or infrastructures. The paper presents a comparison of the two methods for studying avalanche risk on a stretch of road that reaches the village of Planpincieux in Val Ferret (Aosta Valley, IT), highlighting their advantages and drawbacks. Additionally, to demonstrate the flexibility of the multi-criteria risk assessment, a risk analysis was performed on the hotel in Planpincieux hamlet. The key findings illustrate that Wilhelm’s method shines in defining the risk posed by diverse avalanche paths, but is hampered by imprecise parameter definition. McRA, by means of the RC, allows hierarchical and direct assessment of the risk severity at the territory scale but requires hazard intensity maps.