Where the Rubber Meets the Road: Pavement Damage Reduces Traffic Safety and Speed

Road maintenance constitutes a significant component of public transportation spending at all levels of government. Formulation of efficient transportation infrastructure policy requires information about factors affecting road and traffic conditions. We generate the first causal evidence that decreasing pavement quality impacts vehicle crash rates and decreases average speed. Results from Instrumental Variable models using spatially and temporally disaggregated data from Federal-Aid Highway System (FAHS) roads in California show statistically and economically significant increases in vehicle crash rates and decreases in average vehicle speed caused by road damage. These impacts imply significant increases in social costs attributable to road damage.