Longfellow Bridge Cambridge Bound Side Closes for Construction on July 20th – Detour Map

News release from MassDOT on the impending closure of the Boston to Cambridge side of the Longfellow Bridge on July 20th with detour map:


Beginning on Saturday, July 20, 2013, MassDOT will begin major construction activity on the Longfellow Bridge.

As part of the rehabilitation project, the bridge will be closed to vehicular traffic in the Cambridge-bound direction. 

During that time, one travel lane will carry motor vehicles from Cambridge to Boston (using the current Cambridge-bound lane), and Cambridge-bound traffic will be detoured using a signed route from Charles Circle following Charles Street to Leverett Circle, to Monsignor O’Brien Highway/Charles River Dam Road, to Edwin H. Land Boulevard (detour route map is attached).

Emergency response, bicycle, and pedestrian access will be maintained throughout construction.  MBTA Red Line service inbound and outbound will be maintained with the exception of up to 25 service diversions over the course of the project.

The Longfellow Bridge, which connects Boston and Cambridge over the Charles River, is being rehabilitated as part of a three and a half year, $255.5 million effort funded through the Patrick Administration’s Accelerated Bridge Program.  The project will improve the bridge’s structural integrity and capacity, meet modern codes, including ADA accessibility requirements, and create a safer configuration for more modes of travel.

Preliminary work to prepare for construction and the traffic shift began in April 2013 and will be completed by July 20. Traffic signal timing changes, lane restriping, and curb modifications at five area intersections will accommodate the traffic management plan. Overhead highway signs on I-93 and I-90 and portable variable message boards on local roads will provide advance notice of traffic pattern changes. Traffic conditions will be monitored at key locations and through the use of traffic cameras installed as part of the project.

In September 2014, the Boston-bound travel lane will shift its position on the bridge while keeping the Cambridge-bound detour in place.

For more information on the project and traffic management plans, visit the website at For questions or to report issues and concerns related to construction, please call the project hotline at 617-519-9892 or email to be added to the project distribution to  receive project updates and meeting notices.

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