Inman Square Transportation Safety

Photo of Inman Square Intersection East from Vellucci Plaze

The following is information regarding the Inman Square Transportation Safety Study, and interim safety improvements that have been installed to improve current operation of the intersection until the City completes its intersection redesign project.  For more information, and project updates, on the Inman Square Intersection Improvement Project please visit the City of Cambridge Department of Public Works City Construction Projects page here

Inman Square is a vibrant commercial and residential area, with a roadway network that serves high volumes of people who walk, bike, ride transit, and drive. The geometry of Inman Square is defined by the severe skew of the intersection of Cambridge Street with Hampshire Street at this seven-leg signalized intersection. Hampshire Street, Cambridge Street, and Springfield Street all intersect in the Square, and the one-way streets, Antrim Street and Inman Street, branch off the intersection. There are nine pedestrian crosswalks in the Square while three MBTA bus routes travel through the intersection.

The unusual geometry and high number of streets in the intersection cause safety and operational challenges for all users. The size and complexity of the intersection is challenging for bicyclists and drivers, while pedestrians face long delays waiting to safely cross.

In the summer of 2015, the City hired the consulting firm Vanasse Hangen Brustlin, Inc. (VHB) to study the intersection. The goals of the study included improving safety and simplifying operation of the intersection for all users, continuing to support the local residential and business communities, and developing short and mid-term improvements for the Square. The City first shared the results of the study publically in June and the report will be finalized shortly and made available here.

In light of the tragic death of cyclist Amanda Phillips on June 23rd, 2016, the City of Cambridge has implemented interim safety improvements, until the larger intersection redesign project is completed.  See these safety improvements below.  

Latest Safety Improvement Updates

New Left Turn Restrictions, November 3, 2016

Effective November 3rd, the Department of Traffic, Parking, and Transportation will restrict several left turn movements in Inman Square in order to improve the safe operation of this complex intersection.

The following turning movement prohibitions will go into effect on this date:

- No left turn from Hampshire Street southbound (towards Kendall Square) to Cambridge Street eastbound.

- No left turn from Hampshire Street northbound (towards Somerville) to Cambridge Street westbound

- No left turn from Cambridge Street westbound to Antrim Street southbound.

In coming months, the Department will study the impacts of these changes on safety in Inman Square as well as evaluating the impacts on surrounding intersections and neighborhoods.

Variable message boards and advance warning signs will be in place to advise drivers of the change.

Interim Safety Improvements, August 2016

The City has begun implementation of interim improvements to the intersection, including the installation of new pavement markings for cyclists, improved signs, and enhanced pedestrian safety treatments. You can view a plan of the short terms improvements here .Elements of the safety improvement plan include installation of green-backed sharrows, intersection bike lane markings, and improved signage.

Inman Square Green Bike Lane Marking InstallationInman Square Green Bike Lane Marking

Bike Sharrow

Turning vehicles Yield to BikesBicycles May Use Full Lane

We are also deploying enhanced enforcement and educational programs to promote safer behavior on the part of all users.

The City is also moving forward with additional conceptual and design work for more significant, slightly longer term improvements for the entire intersection that are intended to more permanently address current transportation issues within Inman Square. We will provide additional updates on the longer-term improvements as the process moves forward.

July 19th City Council Meeting on Inman Sqaure

On July 19, 2016, the Cambridge City Council held a joint meeting of the Neighborhood and Long Term Planning, Public Facilities, Arts, and Celebrations, Public Safety, and Transportation and Public Utilities Committees, to discuss pedestrian and bicyclist safety in Inman Square.

City staff provided an overview of overall safety efforts, including engineering, education, and enforcement, and presented plans for upcoming short- and longer-term improvements in Inman Square.

View the presentation made by the City administration.

Community Presentation on Safety Improvements, June 22, 2016

The Traffic, Parking, and Transportation Department has been working on a traffic study of the Inman Square intersection, with the goal of addressing safety and congestion issues raised by the community.

On Wednesday, June 22nd, 2016 the Department hosted a public meeting to present initial results of this study, and to discuss potential improvement recommendations. These include changes to traffic signal timing, crosswalks, bicycle facilities, and the design of the intersection, all aimed at improving safety and operations for all users, including more vulnerable users such as pedestrians and cyclists.

The community members at the meetings were enthusiastic about the potential changes, and the Department is planning to move forward with next phases of planning and design, to develop a more detailed improvement plan. In addition, we will pursue short-term safety improvements that can be implemented over the next 3-6 months.

View the presentation from the June 22nd meeting.

View a video of the presentation portion of the June 22nd public meeting.

Resources & Data

The VHB study of Inman Square included extensive data collection. Vehicle, pedestrian, and bicycle count data from the study is available here.


If you have any questions, comments, or would like to receive e-mail notifications on Inman Square, please contact us using this form.