Development of a Methodology for Assessment of Crash Costs at Highway-rail Grade Crossings in Nebraska.

摘要

An accurate measure of crash costs is required to support effective decision-making about transportation investments. In particular, underinvestment will occur if measurement fails to capture the full cost of crashes. Such mis-measurement and underinvestment may be occurring in the case of crashes at highway-rail grade crossings (HRGCs). HRGC crash costs can be substantial because of the severity of crashes. However, another important potential cost is the disruption to the transportation and logistics system. Existing methodologies capture the first set of costs but often fail to fully capture the second set. This research provides a standardized methodology for assessing the expected annual crash costs at HRGCs in Nebraska, and the potential benefits from removing and replacing HRGC sites, for example, with an overhead bridge. Avoided crash costs are the primary benefit of safety improvements but logistics costs savings also are identified. Throughout the report, we trace a scenario using traffic conditions at the mean at-grade highway-rail crossing crash. We find that the cost of a crash, if it did occur, would be $805,675. The lifetime benefit of removing an at-grade intersection and replacing it with an overhead bridge or an underpass would be $235,836 given the traffic conditions at the mean Nebraska HRGC crash site. Given the relatively low traffic volumes found in many parts of Nebraska, at the mean crash site the injuries and deaths associated with crashes are the primary cost, with logistics costs accounting for a small share of costs (though exceeding the share of operating costs for trucks and rail). Naturally, benefits would vary given different traffic condition, with benefits rising if the number of motor vehicles and trains using a highway-rail at grade crossing increases. More generally, in this project we developed a spreadsheet which can be used to calculate the economic costs of individual crashes based on the AADT and detour time on the impacted roadway and train traffic and length of delay on the railway. This spreadsheet is available for simulation purposes and can be paired with information on the likelihood of crashes to determine the benefits of improving the safety of at-grade rail-highway intersections.