About this site

For a summary of the project and its policy implications, read the policy brief.

For more details of methods, data sources, and implications, read the open-access paper:

Millard-Ball, Adam, Ben Silverstein, Purva Kapshikar, Sierra Stevenson, and Chris Barrington-Leigh. 2024. Dividing Highways: Barrier effects and environmental justice in California. Journal of Planning Education and Research, Online First.

For more information: Adam Millard-Ball, Professor of Urban Planning, UCLA

Web mapping design: Theodore Lau and Purva Kapshikar

Website design: Angela Wu

Photography: Claudia Bustamante

Thanks to: Juan Matute


This study was made possible through funding received by the University of California Institute of Transportation Studies Statewide Transportation Research Program, funded by the Road Repair and Accountability Act of 2017 (SB 1). The authors would like to thank the State of California for its support of university-based research, and especially for the funding provided in support of this project.