Assessing the Success of San Francisco's Safer Intersections Project

A new report from the San Francisco Municipal Transportation Agency (SFMTA) details the results of the agency's Safer Intersections Project, which implemented traffic calming interventions at high-crash intersections in the city as an effort to achieve Vision Zero goals and reduce pedestrian and cyclist deaths. According to a press release, "SFMTA found a 17% reduction in average speed (1.7mph slower) and a 71% reduction in the likelihood of a car turning left at higher speeds over 15mph at seven high-crash test intersections." 

The agency used delineator posts, rubber speed bumps, and paint to enhance safety in the test intersections and encourage drivers to make turns more slowly. As part of the project, SFMTA also launched an awareness campaign to educate drivers on safer left turn behavior, funded through a grant from the California Transportation Commission Active Transportation Program. 

From the press release:

By changing the architecture of intersections, we were able to move people toward making safer left turns in the moment. The combination of these physical changes and SFMTA’s educational campaign encouraged safe driving behaviors and increased awareness of how individual actions have an impact on the community.

In light of the project's success, the agency recommends traffic calming treatments as a "standard engineering tool" that can be applied widely at dangerous intersections.