Red Line-Blue Line Connector

Last updated
RED-BLUE CONNECTOR
Headhouse of Charles MGH station, December 2009.jpg
Charles/MGH station, the proposed terminus of the extension
Overview
StatusProposed
Owner MBTA
Locale Boston, Massachusetts
Termini
Stations1 proposed
Service
Type Rapid transit
System MBTA subway
Operator(s)MBTA
Daily ridership12,000 (estimated) [1]
Technical
Line length1,500 feet (460 m)
Track gauge 4 ft 8+12 in (1,435 mm)
Electrification Third rail, 600 V DC

The Red Line-Blue Line Connector, also known as the Red-Blue Connector, is a proposed extension of the MBTA Blue Line, intended to provide a connection to the Red Line, as the Blue and Red lines are the only MBTA Rapid Transit lines that lack a direct connection. The proposed connection would extend the Blue Line 0.4 mi (0.64 km) west from its current terminus Bowdoin, to Charles/MGH station, allowing direct transfers to the Red Line. The longstanding lack of a connection is controversial, partly because it contributes to overcrowding on the nearby Green Line, which is currently the most convenient way to transfer between the two lines. A connection between the Red and Blue lines is intended to relieve pressure on crowded downtown stations, in addition to creating connections between unlinked communities such as Cambridge and East Boston.

Contents

An underground connection between the Blue Line and the Red Line has been considered since the 1920s. However, the connector idea did not gain serious traction until the early 1970s. Progress of any kind on the proposed project was mostly stagnant until 1991, when the Commonwealth of Massachusetts agreed to build a direct connection between the two lines as part of the Big Dig highway project. Along with several other transit projects promised during the Big Dig, the connector was never constructed, and the project was briefly put on hold between 2005 and 2006. [2] In the 2010s, continued interest in the project resulted in a renewed effort to design and build the connector. The lack of progress on the connector has been controversial, as the project has been repeatedly delayed or put on hold despite a significant amount of support from politicians and the public. [3] [4] As of 2024, design is funded through 30%, but no construction funding has been allocated to the project. [5]

Background

The Blue Line and Red Line are currently the only two MBTA subway rail lines without a direct connection; passengers must either ride one stop on the Green (or Orange) lines to transfer, or walk 0.5 miles (0.80 km) on Cambridge Street between Bowdoin and Charles/MGH. [6]

The Green Line has been the most convenient way to transfer between the Blue Line and the Red Line, causing the segment of the line between Government Center and Park Street to be exceptionally congested, notably during peak travel times. This frequently causes significant delays on the Green Line. [7] It currently takes an average of 11 minutes to travel between Government Center and Charles/MGH during rush hour, by way of the Green and Red lines. The Blue-Red connector is estimated to save riders 4 minutes on average between Government Center and Charles/MGH. [8]

Former Connection

A physical rail connection between the Red and Blue Lines existed in the early part of the 20th century (prior to the MBTA assigning the color designations of the subway lines). Railcars from what is today the Blue Line could emerge from a ramp portal surfacing between Joy Street and Russell Street, just beyond Bowdoin station. The railcars would run on former streetcar track down Cambridge Street and then most of the distance to the western end of the Longfellow Bridge, connecting to what is now the Red Line just east of its Cambridge subway portal, near what is now Kendall/MIT station. Because the tracks were unpowered, individual cars had to be towed along the street at night. This connection was never used in passenger service, but was used to transport Blue Line cars to the Eliot Street Yard maintenance shops then located near Harvard Square station. [9] :32 When the Blue Line eventually got its own maintenance shops, the connection was removed and the ramp portal was permanently covered in 1952. [10] [9] :52 [11]

Route and Design

Tunnel

The connector would be located in a tunnel underneath Cambridge Street, entirely within the city of Boston. Various construction methods have been considered over the years, including cut-and-cover (C&C), sequential excavation method (SEM), and a deep-bore tunnel constructed using a tunnel boring machine (TBM). The project was originally conceived as a cut-and-cover tunnel, although there has been significant concern regarding surface-level disruption to Cambridge Street if a cut-and-cover tunnel is to be constructed. A deep-bore tunnel was the preferred construction method from 2010 until 2018 when a deep-bore tunnel was ultimately ruled out in favor of a shallow cut-and-cover tunnel.

Stations

As of 2024, only one station is planned as part of the connector. An underground Blue Line platform at Charles/MGH is planned to be built underneath Cambridge Street to the east of the main headhouse. This will provide a direct transfer between the Blue and Red lines without passengers having to exit fare control.

Bowdoin station is planned to be closed if the connector is constructed, due to construction costs and travel time savings. However, prior iterations of the project included a rebuilt or untouched Bowdoin station. Recent plans for the connector indicated that Bowdoin station is planned to serve as a staging area during construction if the connector is built. [12]

Connector Proposals

Early planning

An extension of the East Boston Tunnel to Charles Street was considered in a 1924 study of Charles station. [13] A 1926 proposal to convert the Tremont Street subway and connecting streetcar lines into a pair of rapid transit trunk lines called for the East Boston Tunnel to be extended south to Park Street station, with through service running between Maverick Square and Brighton using the Commonwealth Avenue line. (Three potential alignments were considered: one running south from Bowdoin, and two running southwest from a relocated Scollay Under.)

One of three potential designs for the Blue Line level at Charles/MGH from the 1986 study Scheme 1 for Charles MGH station from 1986 study.png
One of three potential designs for the Blue Line level at Charles/MGH from the 1986 study

Regional transportation plans from the 1940s to the early 1970s focused on suburban extensions, with no downtown extension past Bowdoin. By the mid-1970s, the rise of Kendall Square as a major employment center, the coming of the Red Line extension to Alewife, and increased traffic to and from Logan Airport created enough demand to justify a direct connection between the Red and Blue lines. A 1974 state plan again proposed an extension to Park Street, while the 1978 and 1983 Program for Mass Transportation updates called for an extension to Charles/MGH instead. [14]

A 1986 MBTA feasibility study for an extension to Charles/MGH evaluated a cut-and-cover tunnel beginning west of Bowdoin Street with no changes to Bowdoin station. The project was then estimated to cost $79–95 million (equivalent to $186224 million in 2023). [15] [16] A 1987 cost-effectiveness study estimated 9,030 daily one-way trips over the extension. [17]

Big Dig

In 1991, the state agreed to build several transit projects as part of the settlement of a lawsuit by the Conservation Law Foundation (CLF) over auto emissions from the Big Dig project. Among these projects was the Red Line–Blue Line connector, which was to be complete by the end of 2011. The reconstruction of Charles/MGH station (rebuilt 2003–2007) was designed to accommodate a future Blue Line platform to the east of the existing headhouse. [18] However, the project was put on hold in 2005 to prioritize other projects providing similar air quality improvements. After another lawsuit from the CLF in 2006, the state agreed to finish designing the connector. [19] [20]

The 2010 Draft Environmental Impact Report (DEIR) instead called for a pair of deeper tunnels bored by a tunnel boring machine (TBM), starting east of Bowdoin station and passing underneath the existing platform. Alternatives with a replacement Bowdoin station west of Bowdoin Street, and without a replacement station, were considered; the latter was recommended due to lower cost and reduced travel time. Keeping Bowdoin station and loop was ruled out because evacuation from a disabled train would not be possible in the confined loop, and the eastbound platform is not long enough for six-car trains. [21] Use of a TBM rather than cut-and-cover construction was intended to reduce construction cost and limit disruption on Cambridge Street. [21] :3–7

Lacking available funding for design and construction, the MBTA did not complete the design of the extension. The possibility of a public-private partnership (P3) to advance the project was considered in 2013. [22] In 2015, the EPA removed the requirement for the MBTA to complete design. [23]

Project redesign

In 2018, the state commissioned a $50,000 study to reevaluate tunneling methods and their associated costs; it found that contrary to the 2010 DEIR, cut-and-cover tunneling could be considerably less costly than a TBM, albeit with more surface disruption. Cut-and-cover was estimated to cost $200–250 million for the tunnel costs alone, compared to $300–350 million for TBM and the $413 million estimated in the DEIR. [24] :28 An MBTA long-range planning document from June 2018 considered a pedestrian tunnel between the Orange Line platforms at State and Downtown Crossing, which would allow transfers between the Red and Blue lines similar to (though considerably longer than) the Winter Street Concourse between the Green and Orange lines. [25] In 2019 and 2023, the MBTA indicated plans to spend $15 million to design the connector in a five-year spending plan. [26] [27]

A conceptual design completed in 2020 called for cut-and-cover construction, with Bowdoin station still planned for closure. The new Blue Line platform at Charles/MGH would have egresses from the existing lobby and an under-construction MGH development on the north side of Charles Street. Total project cost was estimated as $850 million ($740 million for construction including 30% contingency, $50 million for design, $30 million in administration costs, and $30 million for additional rolling stock), with construction lasting from 2025 to 2030. [28] [29] A Notice of Project Change (NPC) was issued on October 2, 2023. [30] In November 2023, the Massachusetts Executive Office of Energy and Environmental Affairs required the MBTA to prepare a Supplemental Draft Environmental Impact Report (SDEIR). [31]

The project has $30M in programmed funding to complete 30% of the design and environmental review. As of June 2024, the connector lacks funding for 100% design and construction. [32]

Related Research Articles

<span class="mw-page-title-main">Red Line (MBTA)</span> Rapid transit line in Massachusetts, US

The Red Line is a rapid transit line operated by the Massachusetts Bay Transportation Authority (MBTA) as part of the MBTA subway system. The line runs south and east underground from Alewife station in North Cambridge through Somerville and Cambridge, surfacing to cross the Longfellow Bridge then returning to tunnels under Downtown Boston. It continues underground through South Boston, splitting into two branches on the surface at JFK/UMass station. The Ashmont branch runs southwest through Dorchester to Ashmont station, where the connecting light rail Mattapan Line continues to Mattapan station. The Braintree branch runs southeast through Quincy and Braintree to Braintree station.

<span class="mw-page-title-main">Green Line (MBTA)</span> Light rail system

The Green Line is a semi-metro system run by the Massachusetts Bay Transportation Authority (MBTA) in the Boston, Massachusetts, metropolitan area. It is the oldest MBTA subway line, and with tunnel sections dating from 1897, the oldest subway in North America. It runs underground through downtown Boston, and on the surface into inner suburbs via six branches on radial boulevards and grade-separated alignments. With an average daily weekday ridership of 101,000 in 2023, it is among the most heavily used light rail systems in the country. The line was assigned the green color in 1967 during a systemwide rebranding because several branches pass through sections of the Emerald Necklace of Boston.

<span class="mw-page-title-main">Blue Line (MBTA)</span> Rapid transit line in Boston

The Blue Line is a rapid transit line in the Greater Boston metropolitan area, one of four rapid transit lines operated by the Massachusetts Bay Transportation Authority (MBTA). It runs from Bowdoin station in downtown Boston under Boston Harbor to East Boston and Revere on the inner North Shore, where it terminates at Wonderland. The stop at Airport Station, by way of a free shuttle bus, is one of two rapid transit connections to Logan International Airport. In 1967, during a systemwide rebranding, the line was assigned the blue color because it passes under the Boston Harbor. With an end-to-end travel time of less than twenty minutes, the Blue Line is the shortest of Boston's heavy-rail lines and the only line to have both third rail and overhead catenary sections.

<span class="mw-page-title-main">Silver Line (MBTA)</span> Bus rapid transit system in Massachusetts, US

The Silver Line is a system of bus routes in Boston and Chelsea, Massachusetts, operated by the Massachusetts Bay Transportation Authority (MBTA). It is operated as part of the MBTA bus system, but branded as bus rapid transit (BRT) as part of the MBTA subway system. Six routes are operated as part of two disconnected corridors. As of 2023, weekday ridership on the Silver Line was 27,000.

<span class="mw-page-title-main">Airport station (MBTA)</span> Rapid transit station in Boston, Massachusetts, US

Airport station is a rapid transit station in Boston, Massachusetts. It serves the MBTA Blue Line and the SL3 branch of the Silver Line. It is located in East Boston under the interchange between Interstate 90 and Massachusetts Route 1A. The station provides one of two mass transit connections to the nearby Logan International Airport, as well as serving local residents in East Boston. Shuttle buses connect the station with the airport terminals and other facilities.

<span class="mw-page-title-main">Alewife station</span> Rapid transit station in Cambridge, Massachusetts, US

Alewife station is a Massachusetts Bay Transportation Authority (MBTA) intermodal transit station in the North Cambridge neighborhood of Cambridge, Massachusetts. It is the northwest terminal of the rapid transit Red Line and a hub for several MBTA bus routes. The station is at the confluence of the Minuteman Bikeway, Alewife Linear Park, Fitchburg Cutoff Path, and Alewife Greenway off Alewife Brook Parkway adjacent to Massachusetts Route 2, with a five-story parking garage for park and ride use. The station has three bike cages. Alewife station is named after nearby Alewife Brook Parkway and Alewife Brook, themselves named after the alewife fish.

<span class="mw-page-title-main">Harvard station</span> Subway station in Cambridge, Massachusetts, US

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<span class="mw-page-title-main">Charles/MGH station</span> Rapid transit station in Boston, Massachusetts, US

Charles/MGH station is a rapid transit station on the MBTA Red Line, elevated above Charles Circle on the east end of the Longfellow Bridge in the West End neighborhood of Boston, Massachusetts. The station is named for Charles Circle and the adjacent Massachusetts General Hospital (MGH) campus. It has two side platforms, with a glass-walled headhouse structure inside Charles Circle. Charles/MGH station is fully accessible.

<span class="mw-page-title-main">Government Center station (MBTA)</span> Subway station in Boston, Massachusetts, US

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<span class="mw-page-title-main">State station</span> Subway station in Boston, Massachusetts, US

State station is an underground Massachusetts Bay Transportation Authority (MBTA) rapid transit station located in downtown Boston, Massachusetts. It is the transfer point between the Orange Line and the Blue Line, and one of four "hub stations" on the MBTA subway system. The Orange Line has two side platforms on two levels, while the Blue Line has two side platforms on a single level. The station is fully accessible.

<span class="mw-page-title-main">North–South Rail Link</span> Proposed rail tunnel connecting Bostons North and South Stations

The North–South Rail Link (NSRL) is a proposed rail tunnel, or pair of tunnels, that would connect North Station and South Station in downtown Boston, Massachusetts, linking rail networks that serve the city's northern suburbs, New Hampshire, and Maine with the rest of the country. The project would build new underground stations near the existing stations, connect them with about 1.5 miles (2.4 km) of tunnels, and add other tunnels to link up with existing surface tracks.

<span class="mw-page-title-main">Science Park station (MBTA)</span> Light rail station in Boston, Massachusetts, US

Science Park station is an elevated light rail station on the Massachusetts Bay Transportation Authority (MBTA) Green Line in Boston, Massachusetts, United States. The station is located at the Boston end of the Charles River Dam Bridge at Leverett Circle. It is at the southeast end of the Lechmere Viaduct, which carries the Green Line over the Charles River. The station is named for the nearby Boston Museum of Science. With 873 daily boardings by a FY 2019 count, Science Park is the least-used fare-controlled station on the Green Line, and the second-lowest on the MBTA subway system after Suffolk Downs.

<span class="mw-page-title-main">Maverick station</span> Subway station in Boston, Massachusetts, US

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The Urban Ring was a proposed project of the Massachusetts Bay Transportation Authority and the Massachusetts Department of Transportation, to develop new public transportation routes that would provide improved circumferential connections among many existing transit lines that project radially from downtown Boston. The Urban Ring Corridor is located roughly one to two miles from downtown Boston, passing through the Massachusetts cities of Boston, Chelsea, Everett, Medford, Somerville, Cambridge, and Brookline. The project was expected to convert 41,500 car trips to transit trips daily.

<span class="mw-page-title-main">Bowdoin station</span> Subway station in Boston, Massachusetts, US

Bowdoin station is a Massachusetts Bay Transportation Authority (MBTA) rapid transit station in Bowdoin Square in Boston, Massachusetts. The station is the downtown terminus of the Blue Line, part of the MBTA subway system. It has a single wedge-shaped island platform located inside a balloon loop. Bowdoin is the only Blue Line station that is not accessible.

<span class="mw-page-title-main">Broadway station (MBTA)</span> Subway station in Boston, Massachusetts, US

Broadway station is a subway station in Boston, Massachusetts. It serves the MBTA's Red Line. It is located at the intersection of Dorchester Avenue and Broadway in South Boston. It was opened on December 15, 1917, as part of the Dorchester Extension from Downtown Crossing to Andrew. The station has a single island platform to serve the two tracks.

<span class="mw-page-title-main">MBTA subway</span> Boston region transit service

The Massachusetts Bay Transportation Authority (MBTA) operates rapid transit, light rail, and bus rapid transit services in the Boston metropolitan area, collectively referred to as the rapid transit, subway, the T system, or simply the T.

<span class="mw-page-title-main">Green Line Extension</span> Light rail system in greater Boston, US

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<span class="mw-page-title-main">Box District station</span> Bus rapid transit station in Chelsea, Massachusetts

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