Analysis of social and environmental benefit components in feasibility studies of railway systems

Rail system projects, which are one of the most important transportation projects, are a policy approach that is often preferred today due to the many advantages they provide. Before the construction of these projects is decided, they need to be filtered through cost-benefit analysis. Within the scope of the thesis, first of all, the cost-benefit analysis parameters used in the evaluation process of the rail system projects are compared on the basis of countries. Some feasibility studies conducted in Turkey were also included in this comparison, and a comparison of the studies conducted in our country with those in other countries was provided. Then, a cost-benefit analysis was carried out for the Çiğli Tram Line project, which was selected as an example. In addition to the parameters generally used within the scope of this cost-benefit analysis, noise pollution, environmental pollution and accessibility parameter were added and new calculations were made. For the noise pollution calculation, the necessary noise values were taken from a joint study covering European countries and calculations were made. In order to measure the effect of environmental pollution parameter on cost-benefit analysis, GaBi software was used. In this way, the environmental effects caused by the construction of the tram line were added to the cost-benefit analysis calculations. In addition, the accessibility criterion, which is one of the most effective tools used to measure the performance of transportation systems, has been used to reflect user benefit in the feasibility study. The cost-benefit analysis calculations were made again with the new parameters added. As a result, the results of 111 902 658 € net present value, 12.42% internal rate of return and 1.68% benefit/cost ratio were achieved. Thus, it has been seen that the tram line is feasible and the use of new parameters such as noise, environmental pollution and accessibility has added a positive effect to the evaluations.