Transportation Bridging the basin - Charles River bridge reconstruction

Traveler information

Project Background

The Longfellow Bridge is the most prominent of eight bridges over the Charles River slated for rehabilitation.The Charles River Basin is home to some of Boston's most iconic landmarks and public spaces: the "salt-and pepper shaker" towers on the Longfellow Bridge, the Esplanade and the Hatch Shell. It is also home to some of the region's most important roadways and bridges. Those roads, and the bridges crossing the river between them, are vital to the region's transportation network ensuring mobility for hundreds of thousands of commuters via transit, bike, walking, and driving everyday.

With the Commonwealth's Accellerated Bridge Program over $360 million in funding has been allocated to improving the conditions of structurally deficient bridges in the Lower Basin area of the Charles River. These improvements will provide a sound infrastructure system for generations. This site will provide you with important information regarding the projects major impacts and milestones, options for avoiding traffic delays, and links to key resources you may need in planning your next trip through the area.




Commuter Options




Airport Access

Meet the


Traffic Impacts & Detours

July 20, 2013- Spring 2017
Longfellow Bridge

MassDOT will begin a three and a half year project reconstructing the Longfellow Bridge, the historic bridge that is a major link between Boston and Cambridge. The bridge currently has many structural deficiencies, and ongoing work will bring it up code and improve multi modal access and bring bring bridge to street connection into compliance accessibility guidelines. The historic nature of the bridge will be preserved, including the 'salt and pepper shakers' while meeting environmental construction standards.

The phased construction will require Cambridge-bound traffic diversions and 25 weekend MBTA Red Line shutdowns over the three and half year project. During the proposed phase 1 weekend diversions, buses will replace Red line trains on the bridge from Kendall to Park St. and Boston-bound traffic will be detoured using Memorial Drive to Land Blvd to allow space for bus travel in each direction. The MBTA scheduled diversion weekends for 2013 are August 10-11, August 24-25, October 19-20, October 26-27 and November 2-3.  


Detour Routes

Effective July 20, 2013 through September 2014, one lane of traffic will carry vehicles into Boston (using the current Cambridge-bound lane) and Cambridge-bound traffic will be detoured using a signed route from Charles Circle to Land Boulevard using Leverett Circle and Monsignor O’Brien Highway. Subsequent to September 2014, the Boston-bound travel lane will shift its position on the bridge while keeping the Cambridge-bound detour in place. You can view the most recent traffic management plan here.
View Cambridge to Boston detours in a larger map

During the 25 weekends of the project when the Red Line is shut down, Boston bound traffic will also be detoured. When the Red Line is shut down, only MBTA shuttle buses will have access across the bridge.

View Boston to Cambridge detours in a larger map

Commuter Options

The more that people commute by bike, walk, public trasit, vanpool, or carpool, the easier it will be to travel over and around the Charles River Basin area. The following is a list of options available aimed at making your commute through the area a bit less stressful.

  • Bicycling
  • MBTA - travelinglongfellow from East Cambridge, Arlington, Somerville into Lechmere Station via bus and transfering to Green Line
    • Bus 69 - Harvard/Holyoke Gate to Lechmere
    • Bus 80 - Arlington Center to Lechmere
    • Bus 87 Arlington Center or Clarendon Hill to Lechmere
    • Bus 88 - Clarendon Hill to Lechmere
    • Bus 92 - Assembly Square Mall to Downtown
  • Vanpools - click for a list of vanpools travel into Boston from points north, west, and south of the city.
  • Ridematching - find potential matches for carpooling
  • Private Bus Operators


Local Transportation Management Associations (TMAs)

Local TMAs provide exemplary commuter benefits programs and transportation services to their members, that are aimed at increasing the use of public transit, ridesharing, biking, and walking. If your worksite or building is a member of a TMA please visit their site for specific promotions they may be operating during bridge construction. If you are not a member of a TMA click here to request information on how you may become a member of these important organizations.

A Better City TMA: serving downtown Boston and the Back Bay.

Charles River TMA: serving Cambridge

CommuteWorks at MASCO: serving the Longwood Medical Area

Seaport TMA: serving the South Boston Waterfront

TranSComm: serving BU Medical Center and the South End


Bicycle Routes

Two-way bicycle traffic will remain open for the entire project. Please be extra cautious riding through a live construction zone. During the weekends when the Red Line is shut down, bikers are asked to walk their bike across the bridge. The Red Line will show down on the weekends of August 10-11, August 24-25, October 19-20, October 26-27 and November 2-3 in 2013.


Traveling to Logan Airport

Via Public Transit

  • Logan Express from Anderson Regional Transit Center in Woburn: offers full-service bus terminals and secure parking at each location with direct service to all of Boston Logan's terminals (lower level).
  • MBTA Silver Line: offers direct connection via silver line bus from South Station to all of Boston Logan's terminals (lower level).
  • MBTA Blue Line: offers direct connection via airport shuttle from Airport Station to all of Boston Logan's terminals (lower level).



Meet the Charles River Basin Bridges

Craigie Dam Bridge craigie_aerial
The Craigie Dam Bridge consists of 9 sluice ways and was constructed in 1906. Project goals include replacing all damaged and deteriorated structural members along with the reconstruction of the bridge deck and the sidewalks.  The pedestrian walkway on the southwest side of the bridge (adjacent to the Museum of Science) has been widened to accommodate pedestrians and bicycles. Visit the Craigie Dam Bridge project site.

Craigie Drawbridge
The Craigie Drawbridge is a Twin Double-Leaf Bascule Bridge was originally constructed in 1910 and replaced in 1962 and 2011. This project includes the complete replacement of the bridge superstructure and bridge deck as well as the machinery and electrical components. During construction temporary bridge structures were utilized to carry traffic.

Longfellow Bridge
The Longfellow longfellow(originally, the Cambridge) Bridge is one of the most architecturally distinguished bridges in Massachusetts. The bridge joins Cambridge Street in Boston with Main Street in Cambridge and carries the Massachusetts Bay Transportation Authority (MBTA) Red Line and two-way vehicular traffic across the Charles River. The bridge presently carries 28,000 motor vehicles, 90,000 transit users, and significant numbers of pedestrians and bicyclists each day.

The bridge today consists of eleven original open-spandrel steel arch spans plus two steel girder approach spans at the Cambridge end. The bridge has an overall length of 2,135 feet, and a deck width of 105 feet, which includes a 27-foot fenced median reservation occupied by the Red Line. The existing cross-section provides an upstream 6-foot sidewalk and a 33-foot wide roadway while the downstream side consists of a 10-foot sidewalk and 29-foot wide roadway. The bridge's substructure is built of granite block masonry and consists of ten hollow piers and two hollow abutments. The two central piers carry the signature pairs of neoclassically inspired dressed granite towers that have given the bridge its popular nickname - the Salt and Pepper Bridge. Visit the Longfellow Bridge project site.

Boston University Bridge
The goals of the Boston University Bridge Rehabilitation Project were to relongfellowstore the bridge’s structural integrity and enhance accessibility. This project included a full deck replacement and the rehabilitation of the downstream sidewalk.  Additional superstructure repair work and a new environmentally friendly drainage system were also installed.  The bridge rehabilitation will preserve as many of the original historic elements as possible. Visit the BU Bridge project site.

Anderson Memorial Bridge
The Anderson Memorial Bridge, popularly known as the “Larz Anderson Bridge,” is a vital transportation link connecting the cities of Cambridge and Boston and the primary connection between two Harvard University campuses.  The bridge is listed on the State and National Registers of Historic Places as an integral and contributing component of the Charles River Basin Historic District. 

The goals of the AndersonAnderson Memorial Bridge Rehabilitation Project are to improve the bridge’s structural integrity and enhance accessibility.  The project will repair deteriorated elements of the bridge, upgrade structural capacity and improve local street connections and accessibility.  The proposed rehabilitation will respect the documented historic status of this landmark structure and preserve as many of the original elements as possible. MassDOT is committed to the goals of minimizing disruptions to all bridge users and maintaining access during rehabilitation construction. Visit the Anderson Memorial Bridge project site. 


Western Avenue & River Street Bridgeslongfellow
The River Street Bridge links the Allston section of Boston to Cambridge via River Street.  Traffic on the River Street Bridge is one-way, eastbound, from Allston into Cambridge.  The Western Avenue Bridge links Cambridge to Allston, via Western Avenue.  Traffic on the Western Avenue Bridge is one-way, westbound, from Cambridge into Allston. 

The purpose of the project is to repair and rehabilitate the foundations and superstructure of the Western Avenue and River Street Bridges to ensure that both bridges are able to continue to safely carry vehicular, bicycle and pedestrian traffic for anlongfellowother 75 years.  Repairs to the bridges will address both structural deficiencies, such as deteriorated concrete, as well as functional deficiencies such as inadequate site lines where the bridges meet Soldiers’ Field Road and Memorial Drive. This work will commence upon completion of the Anderson Memorial Bridge. Visit the Western Avenue & River Street Bridge project site.


Magazine Beach Pedestrian Bridge
This project consisted longfellow of the complete demolition andreplacement of the existing pedestrian bridge over Memorial Drive. This bridge has been severely damaged due to vehicular impact. The new superstructure is designed for a 75-year service life. The project  also includes the installation of an over height detection system and ADA compliant ramps and code compliant handrails. Visit the Magazine Beach Pedestrian Bridge project site.