Los Angeles has made a substantial commitment to rail transit, but several policy questions continue to be debated. Among those questions, possibly the most basic is whether new transportation options will change travel modes, and whether Angelenos will modify their travel as new options become available. Against that backdrop, the results from this research are in some ways striking. We find evidence that the Expo Line is associated with large reductions in VMT, some increase in rail transit ridership, changes in physical activity, and large reductions in GHG emissions among households living within ½ mile of a station. The research design, using a control group to account for factors other than the rail investment, allows us to make causal inferences more strongly than is often the case in social scientific research. In short, the Expo Line is associated with travel behavior change, and we can infer that the association reflects a causal effect of the Expo Line on household
travel. The large impacts for VMT and GHG reduction occur within a small area – ½ mile around six new stations.
Viewed from the perspective of the greater Los Angeles region, these impacts will be small, but they are large in
the neighborhoods surrounding the Expo Line.
Several policy implications follow. First, this is some optimistic evidence for the rail transit investment program in Los Angeles. We did not conduct a formal benefit-‐cost assessment, but clearly the rail line is associated with changes in travel behavior that are consistent with the anticipated effects. Second, the evidence indicates that the travel impacts of light rail are enhanced by local land use characteristics. Bus lines and streets with narrower width are likely to be more conducive to increasing the effects of rail transit, at least based on the results from this study. Third, economic theory predicts that the travel impacts documented here will likely lead to downstream effects including changes in the resident population near Expo Line stations, changes in land prices (and hence rents and house prices), and changes in land uses. It is too early to draw conclusions about those downstream effects, and whether they will advantage existing residents or new residents or a combination of both. Yet, the fact that the Expo Line has changed travel behavior suggests that the rail service is valued by nearby residents. That value will likely be reflected in land prices and land uses in later years, which will lead to broader social and economic impact around the rail transit lines.