The air quality in Medellín, Colombia has worsened in recent years reaching red alert levels in the spring of 2015, 2016, and now 2017. Increased automobile usage and the unique topographical and meteorological characteristics of the Aburrá Valley contribute to higher concentrations of harmful pollutants, causing public health concerns. La Ciudad Verde, a non-profit think tank focused on mobilizing civil society to influence the creation of sustainable policies, has challenged a Columbia University School of International and Public Affairs (SIPA) Capstone team to identify a potential policy path to improving Medellín’s air quality.

The team has mapped the governance structure of Medellín and the greater Aburrá Valley, conducted stakeholder interviews, and analyzed the costs and benefits. The team concluded that the cost of inaction outweighs the costs incurred by society in the long-term. The team identified and recommended a proactive policy scenario in which Medellín prioritizes seven critical transportation sector-related intervention measures based on feasibility and effectiveness.