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.
We thank participants at the 2020 NBER Economics of Transportation in the 21st Century Conference, Ed Glaeser, and Matt Turner for valuable comments and the NBER for financial support. This research was funded through an interagency agreement between the US. Department of Transportation and the National Science Foundation, award no. 1559013. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.