Officials, stakeholders celebrate opening of MBTA's Green Line Extension Union Square Branch

March 22, 2022
The Union Square Branch opened for service on March 21, and extends the northern end of the Green Line from Lechmere in East Cambridge to Union Square in Somerville.

Local, regional and federal officials joined other project stakeholders and community partners to celebrate the opening of the Green Line Extension (GLX) Union Square Branch with a ribbon-cutting event at the Union Square Station and Lechmere Station.

“The Green Line Extension is a transformative project that is the result of collaboration among federal, state, local and community partners and our administration is thrilled to celebrate today’s launch. This expansion of the Green Line will improve access to educational and job opportunities throughout the MTBA system and across the region,” said Massachusetts Gov. Charlie Baker. “This milestone will have a significant impact on this region of the commonwealth by providing better MBTA service to riders and spurring economic growth, and we are grateful to everyone who worked together to make this day possible.”

The new branch will extend the northern end of the Green Line from Lechmere in East Cambridge to Union Square in Somerville. Union Square station will serve the Green Line’s E Branch as of opening day, but will switch to Green Line D Branch service later this year when testing begins on the new Medford Branch.

“The Green Line Extension is already transforming the region, creating so many opportunities for residents,” said Federal Transit Administration Administrator Nuria Fernandez. “The Green Line was the first subway line in America. MBTA is still on the cutting edge, looking for new and better ways to improve access and change people’s lives. I am proud of FTA’s role as this project came to fruition – not only providing a nearly $1 billion Capital Investment Grant – but also our technical assistance throughout the process.”

MBTA General Manager Steve Poftak added, “The opening of the Union Square Branch of the Green Line today marks an incredible achievement for the MBTA and improved transit options for the riders we serve. It also symbolizes the culmination of many years of hard work on the project, even during times of uncertainty. I’d like to thank the Baker-Polito Administration for its continued guidance and support of GLX; our MassDOT partners for their continued leadership; our municipal partners for their eagerness and collaboration; GLX Program Manager John Dalton and the entire GLX team for their dedicated work in propelling this project forward and making this day a reality; the entire MBTA team for their support of this project; and the many stakeholders, advocates, GLX neighbors, and members of the community who have partnered with us and supported the project. This is a great day, and we look forward to officially opening Green Line service along GLX’s Medford Branch later this year.”

The Union Square branch is the first of two segments to be completed on this $2.3 billion design-build. STV serves as the lead designer for GLX as part of the design-build team led by Fluor Corporation/Middlesex Corporation/Herzog Contracting Corp/Balfour Beatty joint venture (GLX Constructors).

“The start of revenue service on the Union Square Branch today represents the collective, sustained efforts of many people for many years,” said MBTA Green Line Extension Program Manager John Dalton. “Advocates, elected officials, engineers, contractors, MBTA employees, city and state employees have persisted to ensure the real beneficiaries of GLX – the riding public – will now have reliable, safe public rail service from Union Square Station in Somerville and soon from Medford/Tufts Station in Medford. As a member of the MBTA’s project delivery team, I want to specifically thank the dedicated professionals of the MBTA’s Program Management Team, the staff and work crews of GLX Constructors, and the residents and neighbors who have been impacted by the construction efforts associated with achieving this historic milestone.”

The GLX design-build program included the design and construction of a vehicle maintenance facility, an administration building, three traction power substations, a viaduct with more than 50 spans, seven stations, six bridges and a community path with a pedestrian bridge. STV says it overcame multiple design challenges to deliver a sustainable and reliable new transit system and responded to the requests of residents by providing bicycle and pedestrian amenities that will connect to other communities, all within an extremely narrow corridor that cuts through the most densely populated area in New England.

More about Lechmere Station

The old Lechmere Station opened with the completion of the East Cambridge Viaduct in 1912 and has served as the terminus point of the Green Line since that time. For the past several decades, the backbone of major economic development and job growth at Lechmere has been the long awaited GLX Project.

The new Lechmere Station that opened as part of GLX is located on the viaduct on the north side of Monsignor O’Brien Highway. Featuring two headhouses located on North First Street and on East Street, the new Lechmere Station includes a new busway with four bus shelters, longer station platforms to accommodate the next iteration of Green Line “supercar” vehicles, storage for more than 250 bicycles (182 covered, 72 uncovered), covered platforms and three elevators. With the reopening of Lechmere, Bus Routes 69, 80, 87, and 88 will now use the new Lechmere Station busway on Water Street.

More about Union Square Branch and Station

Linking one of Somerville’s most highly populated residential and commercial centers to Boston and the rest of the MBTA system, the Union Square Branch of GLX runs approximately one mile parallel to the Fitchburg Commuter Rail Line to Union Square in Somerville. The Union Square Branch’s strategic location will contribute to an estimated removal of 26,000 vehicle trips per day from local streets and provide riders with a one-seat ride from Somerville to Fenway Park and the Longwood Medical Area. Union Square Station is also an important driver of local economic benefits that include significant job growth through developer investment and a stimulated commercial tax base in the area.

With an entrance at Prospect Street in Somerville, Union Square Station features a platform canopy, longer station platforms to accommodate the next iteration of Green Line “supercar” vehicles, two customer assistance areas with emergency call boxes, five platform benches, bicycle storage areas and an elevator to/from the Prospect Street Bridge.

More about GLX

The GLX Project extends the Green Line approximately 4.7 miles along two branches – the Union Square Branch and the Medford Branch – from the relocated Lechmere Station in East Cambridge. The Medford Branch of GLX, which is anticipated to open in summer 2022, will run approximately 3.7 miles parallel to the Lowell Commuter Rail Line to College Avenue in Medford. Seven new stations were constructed as part of the project, including the relocated Lechmere Station, along with a new vehicle storage and maintenance facility in Somerville.

When fully complete, Green Line trains will operate every five to six minutes in the peak periods, providing fast and efficient service in areas that did not previously have access to reliable public transit. GLX will also significantly reduce vehicle emissions on the road by supporting anticipated increased ridership and dramatically improve local and regional air quality when GLX is complete. About 20 percent of Somerville’s population is within walking distance of rail transit today, and 80 percent will be within walking distance to a station at the completion of the project.

GLX was procured through a framework that set strict limitations on the project’s total cost while allowing bidders to include additive options ensuring the MBTA could procure a project that maximized the benefits without jeopardizing its budget. In addition to track infrastructure and seven station stops, construction included six additive options: platform canopies, additional elevators at select stations, public art, an extension of the community path with additional connections and an enhanced vehicle maintenance facility.

The total project cost is nearly $2.3 billion, which includes other project components such as real estate, professional services, contingency and the procurement of 24 new trolleys to augment the existing Green Line fleet. When fully complete, GLX will have installed 100,000 railroad ties, 21,000 linear feet (nearly four miles) of pilings, 22 million pounds of steel (which includes 16.5 million pounds of steel girders), 17 miles of permanent track and two miles of multiuse community path.

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