Cost-Benefit Analysis of Avalanche Protection Projects on Roads
Anders Straume, SINTEF, Dag Bertelsen, SINTEF, Gunne Haaland, Norwegian Public Roads Administration
Road closures caused by several types of avalanches are increasing. The paper refers to a Norwegian method for CBA of avalanche protection projects on roads. Main input data, calculations and results are described, and some examples are shown.
The changes in climate cause changes in weather conditions and patterns. As a result we see an increased trend in road closure caused by several types of avalanches (snow, ice, earth, rock, sludge and flooding). In this paper we describe a method for Cost-Benefit Analysis (CBA) of avalanche protection projects on roads. This method is currently implemented in the CBA tool EFFEKT, used by the Norwegian Public Roads Administration. EFFEKT calculates socioeconomic costs for a set of monetized impacts, and serves as an objective decision making support to an appraisal of relevant advantages and disadvantages which a road investment project will lead to.
The main input data for such analyses includes a description of the road network affected by closure (including alternative routes), road standards, traffic volumes, and various data connected to the current avalanche type(s) expected to cause road closure.
The following main calculations are included in the module:
• The risk of being caught in a primary avalanche, based on traffic volume, avalanche frequency, and the exposed road length.
• The risk of being caught in a neighbour avalanche, based on frequency, road length in the neighbour area, and the number of vehicles being stopped by the primary avalanche. This will occur in situations when a primary avalanche is followed by a neighbour avalanche, and then neighbour avalanche frequency is used.
• Inconvenience costs during the time before and after the road-users get necessary information about the closure.
• Consumer surplus (including time spending costs, vehicle costs, direct costs) for the road-users driving a temporary alternative route, if such exists.
• Accident costs
• Management and maintenance costs
• Environmental costs
The results from the module may be used to evaluate and compare several alternatives of avalanche protection projects. For instance, building a new tunnel eliminates avalanche risks, but commonly has high investment costs. Smaller projects will normally reduce the risks, depending of type of efforts (i.e. building leading dikes, mounting wire nets). However, after such protection projects, residual risk of being caught by an avalanche must be taken into account.
The paper will also include examples where CBA in EFFEKT are used to calculate certain types of projects implemented to reduce or eliminate avalanche risk.
Association for European Transport