Commonwealth Avenue Bridge Project - UPDATED

UPDATE: All Major Summer 2017 Work Has Been Completed!  Commonwealth Avenue and the BU Bridge have been reopened to traffic and normal Green Line and bus service have been restored.

The Commonwealth Avenue westbound portion of the bridge will be replaced next summer (Stage 4: 2018 Construction Shutdown). The 2018 shutdown will last 15 ½ days in July/August with similar impacts as the 2017 Construction Shutdown.

MassDOT will be reducing the number of lanes on I-90 (Massachusetts Turnpike) through Boston and closing the BU Bridge and sections of Commonwealth Avenue to all traffic in July/August of 2018.  The closures are necessary for reconstruction of the bridge that carries Commonwealth Avenue and the MBTA Green Line over I-90 (Massachusetts Turnpike). 

Significant traffic disruptions are expected during the 15 ½-day construction period on the following roadways:

  • I-90 (Massachusetts Turnpike)

  • Soldiers Field Road

  • Storrow Drive

  • Memorial Drive

  • Park Drive

  • Massachusetts Avenue

  • Beacon Street

  • Cambridge Street

  • Harvard Avenue/Harvard Street


The road closures and bridge reconstruction will also impact transit service.  The MBTA Green Line Boston College “B” branch will be replaced with buses between Packard’s Corner and Kenmore Square.  Inbound trips to downtown Boston will require passengers on the ‘B” branch to transfer from a train to a bus at Babcock Street station and then from the bus back to a train at Blandford Street Station. 

MBTA Bus Routes 47 & CT2 will operate across the BU bridge during construction but all buses will detour onto St. Mary's Street around the project limits.

MBTA commuter rail will operate on normal schedules during the week but will be unavailable during some weekends.   

Traffic and transit disruptions will significantly impact travel between the Longwood Area and the following areas:

  • Kenmore Square

  • Central Square and Cambridgeport in Cambridge

  • Allston/Brighton

  • Coolidge Corner in Brookline

  • Logan Airport

  • Downtown Boston

  • Back Bay

  • South Boston Waterfront

  • Newton, Wellesley, Natick, and other communities to the west along I-90 (Massachusetts Turnpike)

Access for emergency vehicles, local abutters, and pedestrians will be maintained through the construction project during the traffic closures.  Access for bicycles will be maintained along Commonwealth Avenue but there is a detour plan for bicycles using the BU Bridge to travel to the Longwood Area.

This page provides updates on the construction project and information on alternative transportation options for employees, students, patients, and visitors to the Longwood Area.  For additional help, please contact the MASCO CommuteWorks Coordinator.    

MassDOT held 3 public meetings on the 2017 Phase of the Commonwealth Avenue Bridge Replacement Project


Latest Project Updates

Some Minor Disruptions Will Continue Through September 2017 as Work is Completed

Through September 2017, the following impacts are necessary for the contractor to carry out finishing work on sidewalks, curb setting, final paving, fencing, and utilities:

  • Short-term and periodic lane reductions on I-90 during overnight hours in the vicinity of the bridge.
  • Off-peak lane reductions on Commonwealth Avenue in the vicinity of the bridge.
  • BU Bridge will remain open to all vehicular, bicycle and pedestrian traffic during this time.
  • A minor pedestrian detour near the bridge due to work on sidewalks (eastbound pedestrians will use the westbound sidewalk between Mountfort/Essex Street and Carlton Street). See Pedestrian Detour Map.
  • Eastbound bicyclists will use a shared lane approaching Mountfort/Essex Street and a temporary bike lane approaching Carlton Street (no bike detours). See Bicycle Route Map.


Transportation Alternatives

Everyone is encouraged to help reduce travel through the area during the 18-day construction period.  Please consider the following options:

  1. Work from home: employees in the Longwood Area should explore their options for working from home during the closures.  Better yet, take advantage of the summer weather to schedule a vacation!

  2. Try Public Transportation: services like the MBTA Commuter Rail, the Orange Line from Wellington, and the Green Line from Riverside or Lechmere are great alternatives to sitting in traffic.

  3. Try Walking or Bicycling: build some exercise into your travel to and from the Longwood Area.  Many institutions in the Longwood Area have showers and locker rooms available to make these options easier for you during the hot summer months.

  4. Change Your Work Schedule: does your employer allow you to work flexible hours or a compressed work week?  If so, it may be easier for you to switch your commuting hours and avoid the added traffic during the bridge reconstruction.

  5. Form a Carpool: create a profile on NuRide to find other area employees who wish to carpool. 

  6. Seek Alternate Driving Routes: travel conditions on I-90 (Massachusetts Turnpike), Soldiers Field Road, Storrow Drive, Memorial Drive, Park Drive, Massachusetts Avenue, Beacon Street, Cambridge Street and Harvard Avenue/Harvard Street will be congested during the bridge reconstruction.  Please avoid travel on these streets as much as possible.


Links to Additional Information