Green Line Extension


The Green Line Extension is an initiative to expand transit services in Greater Boston by extending the Massachusetts Bay Transportation Authority Green Line light rail beyond its current northern terminus at in Cambridge, Massachusetts. The extension is intended to improve mobility and regional access for residents in the densely populated municipalities of Somerville and Medford, two cities currently underserved by the MBTA relative to their population densities, commercial importance, and proximity to Boston.
The project will extend service northward to Medford, near Tufts University, and to Union Square in Somerville using a two-branch operation, both branches to be operated within existing MBTA Commuter Rail rights-of-way. The extension is projected to have a total weekday ridership of about 52,000. The Green Line would see an increase in boardings of 30,700, and the MBTA system would see between 7,000 and 8,000 new transit users.
While on the drawing board since 1990, the project has proceeded in fits and starts. Construction finally broke ground on Phase 1 of the Green Line Extension in 2012, with service targeted to begin in December 2021. Construction reached 20% completion in November 2019.

Route

The Green Line Extension is planned to have two branches, which will split just past a relocated station in East Cambridge. The project's two branches consist of:
Additionally, the project will include acquisition of 24 new Green Line cars and construction of a support facility for storage and servicing of the fleet and existing north side Green Line operations.
The original plans called for a further station,, at the Mystic Valley Parkway in West Medford, as well as an intermediate stop at Winthrop Street and Boston Avenue at the northern edge of the Tufts campus. The Winthrop Street stop was dropped from plans due to the proximity of other stations and neighborhood opposition, while the Route 16 station was placed on hold due to cost issues. In 2011, the Boston MPO decided to allocate funding in the 2016–2020 time period for the Route 16 station.

History

The Lechmere Viaduct opened in 1912, speeding travel times between downtown Boston and East Cambridge. In 1922, Lechmere station was opened as a transfer point between surface streetcars and subway streetcar trains, allowing the Tremont Street subway to act more like a rapid transit service. That year, the Boston Elevated Railway indicated that it expected to eventually extend rapid transit service northwest from Lechmere through Somerville to relieve streetcar crowding at Harvard station.
The Boston Division of Metropolitan Planning's 1926 Report on Improved Transportation Facilities further considered rapid transit conversion of the Tremont Street subway as well as running rapid transit lines along existing mainline railroads to replace inner suburb local stops. The conversion proposal—which would have involved a continuous tunnel running from Lake Street in Brighton to Maverick Square in East Boston, plus a second through route from to Tremont Street in Roxbury—was never implemented except for the partial completion of the Huntington Avenue subway in 1941. However, many of the other extension proposals were partially or wholly completed, with the opening of the Blue Line to in 1954, the Highland Branch conversion to light rail in 1959, the partial conversion of the Reading Hill Line to the Haymarket North Extension in 1977, the extension of the Red Line to in 1980, and the relocation of the Orange Line to the Southwest Corridor in 1987. Two additional projects were considered in the report but not recommended for immediate work: a circumferential route which would reappear years later as the Urban Ring, and an extension of Tremont Street subway through service from Lechmere to Woburn via the Lowell Line.
By 1940, just four streetcar routes remained in Somerville: the 87 Clarendon Hill–Lechmere via Somerville Avenue and 88 Clarendon Hill–Lechmere via Highland Avenue pair, the 89 Clarendon Hill–Sullivan Square station route, and the 101 Salem Street–Sullivan Square station route which connected with the Eastern Massachusetts Street Railway's Fellsway Line to Stoneham. The 87 and 88 were converted to trackless trolleys in 1941, while the 89 and 101 saw heavy wartime use and lasted until 1946 and 1947, respectively.
In the 1945–47 Coolidge Commission reports, many of the same transit projects were again proposed; but this time the Woburn extension was given a high rating. The extension would allow the Boston & Maine Railroad to abandon their local stops along the corridor while providing a faster trip than on surface transit.
However, other extensions received priority, and the Woburn extension was not built. The B&M dropped the last three local stops south of West Medford in 1958 due to declining ridership. In 1955–57 the B&M raised the tracks through and onto a high grade and viaduct in order to eliminate busy grade crossings. However, the elevated portion was only built with two tracks, preventing a rapid transit extension from reaching to Woburn, since two tracks would still be needed for Lowell Line service. All discussion of the project since has focused on an extension no further than West Medford. The trackless trolleys were replaced by buses in 1959 and 1963.

Original GLX project plan

After decades of no action, in 1990 Massachusetts agreed to a legally binding resolution to extend the line through Somerville to offset the additional burdens in traffic and pollution within the city due to completion of the Big Dig project. The current phase of planning began in 2005 with the completion of the MBTA's "Beyond Lechmere Northwest Corridor Study Major Investment Study/Alternatives Analysis".
Despite this legal commitment, however, the Green Line Extension project lagged far behind schedule, prompting the City of Somerville and the Conservation Law Foundation to file a lawsuit to keep the project moving. In 2006, this litigation, with the help of community support and advocacy groups such as Somerville Transportation Equity Partnership and the Union Square Task Force, finally brought about a multimillion-dollar state investment in planning for the Green Line Extension with mandated completion date of December 2014. Potential station stops were announced for the first time in May 2008. In May 2010, MassDOT and the City of Somerville reached an agreement to relocate the planned maintenance facility further into the industrial Inner Belt District, next to the MBTA Commuter Rail Maintenance Facility. The previous site was located along the Medford Branch, slightly closer to a single studio building. In May 2011, the MBTA acquired the property and trackage rights for the relocated Lechmere station from pan Am Railways; in return, Pan Am would receive the existing station parcel for future development.
In 2010, the Massachusetts Department of Transportation announced that the new service was expected to be operational in October 2015; interim air quality offset measures would need to be taken if the project misses its December 2014 deadline as expected. The Department of Transportation had previously announced that due to budget limitations, the portion from College Avenue to Route 16 would be a future second phase of the extension, not included in the current proposed project.
In August 2011, MassDOT announced that opening of the Extension would be postponed to Fall 2018 at the earliest. Completion of the Extension to College Avenue near Tufts University could be delayed to 2020, while the terminus at Mystic Valley Parkway remains deferred indefinitely. The stated reason for the delays was difficulties in land acquisition, as well as implied concerns about cost controls and financing. Interim air-quality improvement measures will be necessary due to the project delays. Possibilities include extending Green Line branches to Lechmere, increased bus service in Somerville and Medford, and adding temporary or permanent commuter rail stops along the GLX corridor.
On June 11, 2012, the Federal Transit Administration approved the Extensions for entry into the Preliminary Engineering phase as part of the New Starts program. This approval was a necessary step in MassDOT's application for $557 million in New Starts funding.
In August 2012, the City of Somerville, MassDOT, and the MBTA reached a memorandum of agreement about the station. Through the Somerville Redevelopment Authority, the City will acquire $8 million worth of land for the station and grant the MBTA a permanent easement. In return, the MBTA and MassDOT will pay for cleanup costs at the site, begin construction by the spring of 2014 and open the station no later than early 2017. In October 2012, the Somerville Board of Aldermen approved the Union Square Redevelopment Plan and authorized an $8 million bond, including $6 million to purchase the land and $2 million for cleanup and station planning.
In December 2014, the FTA said it intended to pay $996 million of the extension's $2.2 billion costs. The remainder of expenses will be paid by the state, from either its operating funds or bonds. On April 18, 2014, Governor Patrick signed a $12.7 billion bonding bill which included $1.3 billion for the Green Line Extension, as well as $2.3 billion for South Coast Rail and $325 million for South Station expansion.
In August 2015, the MBTA disclosed that the project would cost approximately $3 billion, a $1.08 billion increase from previous estimates. The revised cost called into question whether the project could be completed; options like scaling down stations or the maintenance facility will also be considered.
In December 2015, the MBTA ended its contracts with the project's general contractor, project manager, and designer, among others, and announced that while components of the project under construction would continue, no further work would be awarded or started.

Phase 1 construction

Phase I consists of the reconstruction of the Harvard Street Railroad Bridge in Medford and the Medford Street Railroad Bridge in Somerville as well as the demolition of the MBTA facility at 21 Water Street in Cambridge. The MBTA opened bid solicitations for Phase I construction elements, which represent preliminary work that can be done while the main project is in final design, in July 2012. The work includes the $15.3 million reconstruction of the two railroad bridges, as well as the $3 million demolition. Phase I work was to last until early 2015.
Construction on the project began in 2012, with a groundbreaking ceremony held at the Medford Street bridge on December 11 of that year. A Notice to Proceed was issued to the contractor, Barletta Heavy Division, Inc., on January 31, 2013. Surveying began in February, while construction started in March 2013.
The 21 Water Street facility was demolished in August 2014.

Phase 2/2A construction

In September 2013, the state secured funding to move forward on the construction of two new Green Line stations in Somerville, project Phase 2/2A. Construction was expected to begin on two new stations in the Union Square and Brickbottom neighborhoods of Somerville early in 2014, but has not as of early 2016. A new elevated station and a viaduct over the Fitchburg Line will also be built, along with numerous streetscape, bridge, signal, and utility improvements and relocations.
In mid-2013, the MBTA awarded a construction manager-general contractor contract to White Skanska Kiewit, a joint venture of J. F. White Contracting Co., Skanska USA Civil Northeast and Kiewit Infrastructure. WSK was responsible for the primary construction work for Phases 2/2A, 3, and 4. Notice to proceed for Phase 2 pre-construction was given on July 19, 2013. On September 25, 2013, the MassDOT board approved a $393 million, three-year contract with WSK for Phase 2 construction, with funds from the transportation bill passed earlier that year.

Further phases

The main project is divided into three phases. Phase 2/2A, which was to be complete by early 2017, would extend service to on the Union Square Branch, and to on the Medford Branch. A new elevated station and a substantial viaduct over the Fitchburg Line would be built, along with numerous streetscape, bridge, signal and utility improvements and relocations. Phase 3, involves the construction of a substantial new Green Line maintenance facility and several smaller buildings adjacent to the MBTA Commuter Rail Maintenance Facility. Phase 4 is the construction of the remainder of the Medford Branch, with stations at,,, and. Several miles of Lowell Line tracks will be relocated and retaining and noise abatement walls constructed to make way for the Green Line tracks, as well as more bridge, signal, and utility work. The state intends to seek $557 million in federal New Starts money for Phases 3 and 4. Some of this work was underway as of October 2017.

2016 revised plan

On May 9, 2016, the GLX Interim Project Management Team submitted a report outlining a redesigned project to the MassDOT Board of Directors and the MBTA Fiscal & Management Control Board, which then voted to ‘support advancing the Green Line Extension Project and Federal Transit Administration review and approval of the redesigned GLX Project'.
The first step will be resubmitting the revised plan to the FTA for approval. If approved the remaining work will be reprocured using the design–build project delivery method, a process expected to take 18 months if done on an expedited basis. Construction would then take between 43 and 47 months.
To achieve needed cost savings a number of elements of the project were simplified or dropped. Stations were to have open platforms with several shelters, similar to the Riverside Line. Amenities such as escalators, redundant elevators, fare gates, personnel rooms, toilets, extra structure for The RIDE drop-offs, and canopies were to be eliminated at most stations. Bike storage was still to be provided at all stations. The Vehicle Maintenance Facility was to be reduced by roughly half, with storage for 44 Green Line vehicles instead of 88 in the previous design. Three bridges, at Lowell, Medford and School Streets, that were to be replaced will be retained, with the westbound GLX track tunneling behind abutments. The College Avenue Bridge will not be widened. The Broadway Bridge project was simplified and the bridge will be fully closed during reconstruction.
The extension of the Somerville Community Path was to be trimmed back to terminate at Washington Street, Somerville, instead of Water Street in Cambridge. The new path design shifts from the west side of the track to the east side and then back again between Central Street and School Street and has fewer entrances from cross streets. South of Washington Street, bike commuters would have to use city streets, including the McGrath Highway, to reach the Charles River bike path network and downtown Boston.

2017 contract

The Federal Transit Administration approved the modified $2.3 billion plan on April 4, 2017. The first federal funds for the project were received in July 2017.
The contact was rebid with a provision for the optional restoration of six of the elements deleted in the 2016 plan. On November 17, 2017, the MBTA selected GLX Constructors to build the project. The consortium's base bid was $954 million—well below the state "affordability limit" of $1.319 billion - and the total cost will be $1.08 billion. The total cost encompasses all six optional elements, including canopies and additional elevators at stations, public art, a full-size vehicle maintenance facility, and the full extension of the Somerville Community Path to Cambridge, but at a narrower, 10-foot, width..
The new line is expected to be completed at the end of 2021, with some stations possibly opening that summer.
On December 21, 2018, the first of 24 new Green Line vehicles, purchased as part of the GLX project, went into regular passenger service. The shells and frames for the low-floor CAF cars are fabricated in Spain, with final assembly in Elmira, NY.

Criticism

Terminus location

In 2008, the EPA ratified the Massachusetts State Implementation Plan to include an amendment to the 1994 agreement that substituted the planned "the Green Line extension to Ball Square/Tufts University" with an "extension to Medford Hillside... spur to Union Square". Accordingly, the MBTA and MassDOT surveyed potential termini at the intersection of Winthrop Street and Boston Avenue, and also at Route 16, but these locations were abandoned by the agencies, citing budgetary limitations. Instead, the Green Line Extension was retracted by a mile to College Avenue, which is encompassed by Tufts University.
The plan to terminate the GLX at College Avenue drew criticism from residents in Medford and Somerville, who questioned the advantages and legality of the move. A petition by the Medford Green Line Neighborhood Alliance to extend the Green Line argued that a Route 16 terminus would "provide Green Line access to thousands of people within a 10-minute walk," be "conveniently located on two major thoroughfares with existing bus connections," and "serve two large portions of Medford and Somerville designated as Environmental Justice Communities".
In January 2012, the MBTA and MassDOT issued a response to questions from the public. The document stated that "the position of MassDOT and the MBTA on the configuration of the Green Line Extension is supported and has been reinforced by multiple regulatory agencies overseeing the SIP, including MassDEP." In concluding these comments, the MBTA stated that it would not respond to any further questions regarding College Avenue satisfying the Medford Hillside requirements of the SIP.
closed on May 23, 2020 to allow the old viaduct to be partially demolished and connected to the new line north.
Construction of the Route 16 station was planned from Boston MPO funds for 2016–2020 after the rest of the line was complete. However, after the cost overrun this funding was reallocated to the main project. Route 16 is still in the state's plan, with environmental review proceeding, as of 2017.

Lechmere closure

During construction, the northern section of the Lechmere Viaduct will be removed and the elevated section of the line will be extended to a large flyover bridge crossing the Fitchburg Line tracks. The 1922-built Lechmere station will be replaced with an elevated station across the street. The work was expected to require closing the viaduct for 17 months—the third major disruption of Lechmere service since 2004—causing opposition to the closure in Cambridge. In November 2019, plans were revised to reduce this to 11 months. Lechmere station closed for Green Line service on May 24, 2020; it continues to be used as a transfer point between MBTA bus routes and the Lechmere–North Station shuttle buses. Demolition of the northern section of the Lechmere Viaduct began on June 6, 2020.

Station listing

Official sites