California Air Resources Board

Principal Investigator/Author: Douglas Houston

Contractor: University of California, Irvine

Contract Number: 12-313

Project Status: Completed

Relevant CARB Programs: Climate Change

Topic Areas: Behavioral Change, Sustainable Communities

Research Summary:

This study evaluated the impact of the Expo light rail transit (LRT) line, which began service in south Los Angeles in 2012, on the travel and activity patterns of both long-term residents and those who moved to the area after service began. Findings support the implementation of Senate Bill 375 (SB 375) by evaluating the potential of transit investments for promoting compact, transit-oriented development goals of reducing vehicle miles traveled (VMT) and increasing active travel. Based on a quasi-experimental, longitudinal research design, results for longer-term residents indicate that living within walking distance (1 kilometer) of the line was associated with a reduction of 11 household VMT per day, a change likely due to their reduction in average car trip length. Living near the line was not associated with a significant increase in walking or bicycling trips. Residents who moved to the area after service began tended to be younger and had higher rental rates and income; those within walking distance of a station drove 8-10 more VMT per day and took longer car trips compared to longer-term households near a station but had rail ridership rates which were more than double that of longer-term households near a station.

NOTE: ARB is funding the third phase of data collection and analysis for this project. For the results from the first two phases of this project, reach out to the University of Southern California Sol Price School of Public Policy.

Final Report: Please email research@arb.ca.gov to request the final report generated by this research contract.