Commonwealth Avenue Bridge Project - UPDATED

UPDATE: Commonwealth Avenue and the BU Bridge will be shut down between July 26th-August 11th to accommodate Phase 4 of the Commonwealth Avenue Bridge Replacement Project.

The Commonwealth Avenue westbound portion of the bridge will be fully replaced during this 16-day closure. (Stage 4: 2018 Construction Shutdown). Unlike last summer, during this phase of construction the BU Bridge will be closed to buses.  Vehicles and buses will have no access across the bridge. 

MassDOT will be reducing the number of lanes on I-90 (Massachusetts Turnpike) through Boston and closing the I-90 Eastbound on-ramp from Cambridge Street/Soldiers Field Road, the BU Bridge and sections of Commonwealth Avenue to all traffic in between July 26th and August 11th.  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 16-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 detour across the Massachusetts Avenue bridge during construction.  Route CT2 will not provide service in Cambridge west of Massachusetts Avenue and both routes will not provide service to bus stops between Commonwealth Avenue and Audubon Circle in Boston.  

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 around the project area for bicycles currently using the BU Bridge to travel to the Longwood Area.  Please note that due to the constrained conditions at the base of the BU Bridge, bicycles will need to be walked between the BU Bridge and the Carlton Street crossing. 

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 2 public meetings on the 2018 Phase of the Commonwealth Avenue Bridge Replacement Project


Latest Project Updates

I-90 Lane Reductions in Boston for Dry Run, June 1st-3rd

From 9:00 PM on Friday, June 1st to 5:00 AM on Sunday, June 3rd MassDOT will reduce I-90 between the Allston Interchange and the Beacon Street Overpass to two lanes in both directions.  This will allow MassDOT and its contractor to conduct necessary preparation activities and a "dry run" of the I-90 traffic logistics for Stage 4 of the reconstruction project.  A "crossover will be in place on I-90 that will direct all vehicular traffic to either the eastbound or westbound roadways at different periods of time.

The I-90 Eastbound on-ramp from Cambridge Street/Soldier's Field Road will be closed during this timeframe.  The I-90 Westbound Exit 20 off-ramp to Brighton/Cambridge will be closed intermittently.  

There will be no impacts to the MBTA Green Line, Commuter Rail, or local vehicular traffic during this weekend.


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 Bay State Commute 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