Reliability Benefits of Rail Investment Projects
F Savelberg, P Bakker, KiM Netherlands Institute for Transport Policy Analysis, NL
The study aims at improving the way benefits of a better reliability of rail travel times are assessed, measured and validated. It focuses on the situation in the Netherlands, but also compares with similar practices elsewhere.
Better accessibility of urban areas and a more sustainable society are two important policy goals of public transport and rail travel in particular. Rail investment projects usually aim at shorter travel times, higher frequencies and less travel costs. These quality factors predominate in project appraisal methods like cost-benefit-analysis (CBA). A more reliable rail system is also regarded to be an important quality aspect, but often has limited impact in these appraisal methods.
Our study aims at improving the way benefits of a better travel time reliability are assessed, measured and validated. It focuses on the situation in the Netherlands, but also compares with similar practices elsewhere.
The paper starts defining travel time reliability from the viewpoint of passengers, including the differences and overlaps with concepts like train punctuality and network robustness. It describes the present practice, in which reliability often is limited to train punctuality. We illustrate present performances in the Netherlands with those in comparable countries. Next, we have identified several aspects of travel behaviour which in our view should be implemented in a reliability analysis in order to get a more accurate and complete picture. Two examples are the impact of train delays on door-to-door travel times and the so called ?anticipating behaviour?: before starting their journey, public transport users often calculate extra travel time in order to compensate for possible journey delays. We established proper indicators for expressing these aspects and propose ways to incorporate them in project appraisal methods. We conclude with a step-by-step overview that leads to determination of the effects of investments in rail travel reliability.
The result of our study is a more accurate assessment of the social benefits of reliability improvements in rail travel.
Association for European Transport