City-wide cycling network extension and bicycle ridership in São Paulo: A causal analysis

Over the past 15 years, São Paulo, a megacity in Southeastern Brazil, has tackled its enduring mobility challenges by constructing over 500 km of bike routes and supporting various cycling initiatives, including recreational cycling programs, mobility strategies and bikeshare. Despite the generally positive impacts of these initiatives, the absence of robust causal evidence on their benefits can pose serious challenges for future investments in light of the existing social dynamic favoring the use of automobiles. Driven by the need to reduce motorized transport in Brazilian cities, we investigate the causal effects of bicycle routes on ridership between 2007 and 2017, focusing on travellers highly exposed to bike routes developed between 2008 and 2015. Using Difference-in-Differences models alongside Household Travel Surveys conducted before and after the interventions, we observed a modest but positive increase in cycling mode choice probability, ranging from 0.60 % to 1.37 %, among the highly exposed treatment groups. Our findings provide policymakers with valuable insights to support future cycling infrastructure planning and investment, demonstrating their potential net benefits even in car-dependent urban areas. By integrating these results into existing economic appraisal tools, policymakers can further assess additional benefits related to physical activity, health, and emissions reduction.