Discrete-Event Simulation Approach for Evaluating the Transit Capacity of the Istanbul Strait

In this study, a discrete-event simulation model was developed to evaluate the marine transit capacity of the Istanbul Strait, one of the most complex and strategically important waterways in the world. The model was built based on current transit rules, real-world traffic data, and expert insights. Three independent variables were considered in the scenario analyses: annual vessel arrival volume, average vessel entry interval, and the annual proportion of large tankers. The effects of each variable on transit capacity and vessel waiting times were examined. The results show that, based on the threshold criteria and model assumptions adopted in this study, the transit capacity of the Istanbul Strait under the current service level is approximately 42,600 vessels per year. A moderate improvement in service level, examined in an exploratory analysis, produced an estimated transit capacity of around 45,500 vessels. The scenario results indicate that average vessel waiting times are mainly affected by the annual vessel arrival volume and the average vessel entry interval, whereas the proportion of large tankers has the weakest influence. These findings may provide a quantitative basis for marine traffic planning in the Istanbul Strait. The modeling framework can be adapted to other narrow and congested waterways facing similar operational and regulatory constraints.