The Federal Railroad Administration developed GradeDec, a highway-rail grade crossing investment analysis tool, to provide grade crossing investment decision support. GradeDec provides a full set of standard benefit cost metrics for a rail corridor, a region, or an individual grade crossing. Model output allows a comparative analysis of grade crossing alternatives that are designed to mitigate highway-rail grade crossing accident risk and other components of user costs including highway delay and queuing, air quality, and vehicle operating costs.
GradeDec is intended to assist state and local transportation planners in identifying the most efficient grade crossing investment strategies. The GradeDec modeling process can encourage public support for grade crossing strategies, including closure and separation, where project success often depends on getting the community involved in the early planning stages. GradeDec computes model output using a range of values for many of the model inputs. This process allows individual stakeholders to influence how different investment options are weighed and evaluated.
GradeDec implements the corridor approach to reducing accident risk that was developed as part of TEA-21's Next-Generation High-Speed Rail Program. This approach can be an effective means of reducing the overall capital costs involved in constructing facilities for high-speed passenger rail service (at speeds between 111-125 miles per hour), where grade crossing hazards and mitigation measures can be a major cost factor. The corridor approach can be used to demonstrate that acceptable levels of accident risk have been reached for all rail corridors, train types, and speeds. For example, exceptions to the proposed federal rule mandating whistle sounding at all highway rail-grade crossings can be made by showing that appropriate safety measures have been taken to mitigate the additional risk otherwise presented by trains not sounding their horns. GradeDec uses simulation methods to analyze project risk and generate probability ranges for each model output, including benefit cost ratios and net present value. The software also analyzes the sensitivity of project risk to GradeDec 2000 model inputs to inform users which factors have the greatest impact on project risk.
Questions concerning GradeDec should be addressed to:
Karen McClure, Policy Analyst
Office of Policy and Program Development