Research Team: Jae Hong Kim (lead), Jesus Barajas, Douglas Houston, and Nicholas Marantz
UC Campus(es): UC Davis, UC Irvine
Problem Statement: To reduce vehicle miles traveled (VMT), developed areas of California must add residential density. To date, much of the research on densification has focused on increasing density in areas with existing high‐quality rail transit. In California, many areas with high‐quality transit also have disproportionately large numbers of low‐income residents, many of whom are members of racial and ethnic minority groups. As a result, proposals to densify these areas have raised concerns about displacement and gentrification. To equitably promote socioeconomic mobility while reducing VMT, areas that lack rail transit access but have bus access and/or other built environmental features previously associated with reduced VMT must also densify. The University of California Institute of Transportation Studies report, “Driving California’s Transportation Emissions to Zero,” prioritizes such areas for residential development, as do recent changes in California law governing accessory dwelling units, lot splits, and small multiple‐unit dwellings (i.e., duplexes, triplexes, and quadplexes). Given the high costs and political challenges associated with rail expansion, areas that currently lack rail access must seek alternative strategies to mitigate congestion and VMT.
Project Description: This project will identify effective, sustainable, and equitable densification strategies in areas that lack rail access, with careful consideration given to their unique challenges and opportunities. This work will be accomplished by combining quantitative and qualitative methods to analyze patterns of relationships among density, transit, and VMT, and draw useful lessons for practice. One component of this project, led by UC Irvine, will focus on Los Angeles County and Orange County where a broad spectrum of neighborhoods have varying transit availability and other supply‐side conditions. The other component, led by UC Davis, will examine barriers and strategies relevant to non‐rail development in Southern California and across the state. These research findings will expand opportunities to develop and implement more context‐specific densification strategies (consistent with Senate Bill 9 and other ongoing efforts in California), while mitigating the burden on low‐income communities with existing rail infrastructure and enhancing anti‐displacement efforts.
Status: In Progress