ARB Research Seminar

This page updated July 6, 2015

Evaluating the Benefits of Light Rail Transit

Photo of Douglas Houston

Douglas Houston

Photo of Marlon Boarnet

Marlon Boarnet

Douglas Houston, Ph.D., Planning, Policy, and Design; Urban and Regional Planning, University of California, Irvine; Marlon Boarnet, Ph.D., Price School of Public Policy, University of Southern California

July 22, 2015
Cal EPA Headquarters, 1001 "I" Street, Sacramento, CA

Research Project


Available research cannot definitively demonstrate causal association between new transit service and travel behavior change, but there is a pressing need to estimate the potential magnitude of the causal effects of transit investments in ways that are policy-relevant. This research project innovates by applying an experimental - control group research design to study a new light rail transit service in Los Angeles, California. Only two previous studies use an experimental design to assess the impacts of light rail transit, and this study is the first to use an experimental design to measure impacts on vehicle miles traveled--a key determinant of greenhouse gas emissions from the transport sector. We administered a seven-day travel study to a panel of households in the vicinity of Los Angeles' Expo light rail line before the 2012 start of rail service and twice after the line opened. We find that households within walking distance (1 kilometer) of the new light rail drove approximately 10 fewer miles per day relative to control households farther away. Rail transit trips among near-station households approximately tripled relative to households located more than 1 kilometer from stations.

The driving reductions among households within walking distance of new rail transit stations are significant and suggest that household travel behavior responds to transit service enhancements. As cities worldwide focus on alternatives to automobile travel, this study provides results and an evaluation method that can help guide planning practice. The observed driving reductions suggest that Los Angeles' large rail transit investment has the potential to help achieve climate change policy goals. More broadly, experimental evaluation can provide insights into causality and patterns of travel behavior change associated with planning policies.

Speaker Biography

Douglas Houston, Ph.D., is an Associate Professor of Planning, Policy, and Design and Director of the Master of Urban and Regional Planning program at the University of California, Irvine. Dr. Houston's research focuses on the environmental and health implications of urban development and transportation systems, and developing and evaluating planning and policy strategies to address the harmful impacts of the built environment and to promote livable communities. His work has appeared in the Journal of Transport Geography, Environment and Planning A, and the American Journal of Public Health and draws from the fields of urban planning, environmental health sciences, and public health to assess the environmental and land use implications of vehicle-related air pollution for residents of goods movement corridors and to evaluate the implications of compact development and transit investments on travel behavior and activity patterns. This work has received support from the California Air Resources Board, the California Department of Transportation, the University of California Transportation Center, and the California Endowment and uses travel surveys and real-time location and pollution tracking techniques to inform policies seeking to make neighborhoods more compact, mixed-use, and transit accessible in hopes of reducing vehicle travel and associated air pollution. He received his Ph.D. in Urban Planning from UCLA in 2008 and was a postdoctoral fellow in the UCLA School of Public Health before joining the UCI faculty in 2009.

Marlon Boarnet, Ph.D., is Professor of Public Policy and Senior Associate Dean for Academic Affairs in the Sol Price School of Public Policy, University of Southern California, also serving as Director of Graduate Programs in Urban Planning and Development. Dr. Boarnet's research focuses on land use and transportation, links between land use and travel behavior and associated implications for public health and greenhouse gas emissions, urban growth patterns, and the economic impacts of transportation infrastructure. Dr. Boarnet is a fellow of the Weimer School of the Homer Hoyt Institute for Real Estate and serves on the governing board of the Association of Collegiate Schools of Planning. From 2002 through 2014 Boarnet co-edited the Journal of Regional Science. Dr. Boarnet has published over 80 articles, book chapters, and non-book-length monographs. Professor Boarnet was a member of the National Academy of Sciences/National Research Council Committee on "Relationships Among Development Patterns, Vehicle Miles Traveled, and Energy Consumption." Dr. Boanet has been principal investigator of funded research, supported by agencies which include the U.S. and California Departments of Transportation, U.S. EPA, California Policy Research Center, California Air Resources Board, and the Robert Wood Johnson Foundation.

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