Transit neighborhoods, commercial gentrification, and traffic crashes: Exploring the linkages in Los Angeles and the Bay Area

Gentrification impacts commercial areas in various ways, bringing new businesses and displacing old ones. Recent studies have found links between gentrification and transit-oriented development (TOD) around stations. But little is known about how gentrification affects pedestrian and cyclist safety. This study analyzes collision patterns around 81 rail stations in Los Angeles County and 132 rail stations in the San Francisco Bay Area between 1997 and 2015, examining if such patterns are different between gentrified and non-gentrified commercial stations. We find that in both regions, the mean number of annual collisions at commercial stations that have experienced gentrification is over two times higher than at commercial stations that have not experienced gentrification. We construct multivariate regression models of automobile-pedestrian and automobile-bicycle collisions based on population, urban form, and gentrification data within a half-mile area around the stations, and find that pedestrians and cyclists are at a higher risk of collision around commercially gentrified stations relative to non-gentrified ones in Los Angeles County, but not in the Bay Area. Our final models explain from 55% to 77% of the variation in station area collisions. These findings have significant implications for cities that wish to concentrate development around stations.