Measuring transit service impacts on vehicle ownership and use

In this paper we measure the impact of public transportation on household vehicle ownership and use. Advanced econometric models are estimated on household travel survey data and on geographic data. In particular, data from the 2009 US National Household Travel Survey is merged with geographic information obtained from the General Transit Feed Specification source. The integration of variables specific to the spatial and temporal coverage of the transit service allows the analysis of different policy scenarios. Results obtained for the Washington DC Metropolitan Area indicate that enhanced transit services reduce the number of private vehicles and vehicle miles traveled. Effects are more marked when bus services are improved and on car use. The study is important for all Metropolitan Regions that are dealing with the problem of congestion, high levels of greenhouse gas emissions and that are planning to invest in more efficient and accessible public transportation services.