Refining Protocols Following Serious Crashes

Since Cambridge’s adoption of Vision Zero in 2016, the City has had a protocol in place to respond to fatal traffic crashes. Soon after a fatality,

a multi-disciplinary team of staff from departments across the City conduct a site visit to evaluate the location of the fatal crash for opportunities for short- and long-term improvements.

For example, after fatal crashes occurred in Harvard Square, short-term improvements included the accelerated installation of a quick build separated bicycle lanes on Mass Ave between Harvard Yard and the Out of Town News Kiosk, and the elimination of a travel lane on Mass Ave in front of the COOP in advance of capital construction projects. A fatal crash in Inman Square accelerated a redesign and reconstruction of the entire square with the City investing approximately $10.4 million in the greater area. Work included a new lighting system throughout, traffic signal systems, accessibility improvements, and other reconstruction improvements.

The City is now developing an enhanced Safety Audit program that will formalize the process of evaluating locations where fatal or serious crashes occur, as well as proactively identifying, assessing, and mitigating intersections in need of safety improvements. This will include evaluating crash histories, identifying a prioritized list of intersections, and developing a plan to make ongoing improvements. At this point, the framework is still under development and subject to change. Additional information is expected to be provided in the fall of 2024.

In order to prioritize the work, City staff is examining the crash histories at intersections across the City. Analysis is initially focused on City-owned intersections where necessary changes can be made internally.

State-owned intersections are among the highest crash locations within our borders. However, we are analyzing those locations independently of City-owned locations and will work closely with state agencies as a parallel effort to address safety on state-owned roads, including Memorial Drive. For each intersection evaluated, a technical memo explaining the audit process, findings, proposed improvements, and timelines for implementation will be prepared. The final report will be published to the City’s Vision Zero website.

The City is also in the process of refining its methodology for weighting and ranking crash data. Raw data shows a simplistic view of how many crashes are reported, but does not account for a variety of important factors that will be examined, including the involvement and/or injury of vulnerable road users, severity of injuries, and involvement of large vehicles.