Effects of Superblocks on Travel Demand: A Cost–Benefit and System Dynamics Analysis

Abstract

Car-oriented urban development has led to congested and polluted cities. Wide use of private vehicles reduces the public space for other transport modes, pedestrians, and other activities. So, there is a need to reorganize the urban space to discourage excessive car usage by creating more public space for other uses and forcing more sustainable urban mobility. The superblock model, a strategy that restricts cut-through traffic within designated areas, offers a potential solution. However, superblocks may shift cut-through traffic toward its boundaries or other parts of the network, creating an imbalance between the car-free inner area and the outer area. Therefore, this study aims to assess the costs and benefits of implementing superblocks through the generalized cost of transport (travel time, externalities, and other benefits) for a theoretical city resembling the Barcelona superblock proposals. Several scenarios are evaluated with varying traffic demand and number of superblocks. Finally, a system dynamics analysis is carried out to expand on the conclusions and propose recommendations to policy and decision makers. Results suggest that when implementing superblocks under high traffic demand, the increase in the generalized cost calls for complementary measures. Moreover, the resulting induced modal shift might not be enough to ensure an enhanced ex-post scenario in terms of externalities. Finally, traffic evaporation phenomena must be evaluated critically because they may not directly translate to societal benefits. We propose policy recommendations accordingly.