Providing affordable housing and reducing greenhouse gases are common goals in cities worldwide. Transit-oriented development (TOD) can provide an opportunity to make incremental progress on both fronts, by building affordable housing near transit and by providing alternative transport modes such that households reduce driving. While the existing literature has focused on the relationship between TOD and housing and TOD and greenhouse gas emission reduction as separate issues, it has seldom touched on the possibility that TOD could address both goals jointly. We provide evidence to show that focusing on either housing affordability or greenhouse gas emission reduction in isolation can lead to strategies that achieve one goal to the detriment of the other. Using the case of Los Angeles, we develop a scenario planning model that allows simultaneous consideration of housing and transportation goals, and illustrates the tradeoffs of different policy approaches. The results show that larger increases in residential densities combined with a small inclusionary housing requirement yields greater benefits, in terms of both reduced driving and more affordable housing, than would a higher inclusionary percentage with smaller increases in density.
Marlon Boarnet is professor of public policy and chair of the department of urban planning and spatial analysis in the Sol Price School of Public Policy at the University of Southern California. Prior to that appointment, he served as Vice Dean for Academic Affairs in USC’s Price School. Boarnet also served as Director of Graduate Programs in Urban Planning and Development at USC Price from 2012 through 2015, directing one of the nation’s largest and oldest Master of Planning degrees and directing the Ph.D. in Urban Planning and Development. 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.