Enhanced port-city interface through infrastructure investment: evidence from Buenos Aires

Road congestion is a critical challenge facing port-cities. While policymakers can rely on several solutions to minimize seaport externalities in host metropolitan areas, and enhance reliability in freight transport, there is limited evidence on the effectiveness of such policies. This paper explores the exogenous variation, generated by the random inauguration date of a major road infrastructure project, to estimate its impact on the level of urban congestion in Buenos Aires during 2019, one of the most important port-cities in Latin America. The aim of the project is to separate urban from port-related traffic. Leveraging a dataset of more than 40 million traffic observations in 2019, we use a Regression Discontinuity in Time (RDiT) model, accounting for the temporal dynamics of road congestion and controlling for confounding effects. Results suggest an 18% reduction in congestion in the port area, after the infrastructure was inaugurated, with a cumulative congestion reduction of 60% by the end of 2019. Our results provide useful guidance to transport planners and port authorities in their design of effective measures to reduce seaport-caused externalities in port-cities, particularly in developing countries.