A Study of Beirut Rapid Transit System Using Probabilistic Approach

The need for sustainable transportation in Lebanon has become more critical than ever as a result of the high amount of energy required by the transport sector coupled with the large quantities of greenhouse gas emissions by this sector both of which has a direct effect on the social, economic and environmental status of Lebanese citizens. A proposed project, the bus rapid transit (BRT) project supported by the World Bank, is a major step towards achieving the sustainable transportation system. Yet, the realization of this goal is highly dependent on the effectiveness of this project. This research presents a probabilistic cost-benefit analysis (CBA) on the BRT section that spans from Tabarja to Beirut. The CBA accounts for all the costs incurred to construct and operate the system, whereas the benefits considered are savings in travel time, emissions, and crash cost. Using the probabilistic approach is adopted considering the high uncertainties that surrounds the BRT design variables. The probabilistic approach is performed using Monte Carlo Simulation where the uncertain parameter in the CBA analysis are identified and their probability distributions are constructed that can better represent the variability in these parameters. This approach has proven that modal shift is a key element to the success of the project. Finally, a financial analysis is conducted showing that an operating subsidy is needed if the fare revenues are lower than 20%, thus the prominence of modal shift and the number of BRT passengers.