North–South Rail Link

This article needs to be updated. Please help update this article to reflect recent events or newly available information. (May 2024)

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "North–South Rail Link" – news · newspapers · books · scholar · JSTOR (December 2012) (Learn how and when to remove this message)

North Station

South Station

class=notpageimage|

The North–South Rail Link would close a 1.5-mile (2.4 km) gap at the center of the regional rail network.

The North–South Rail Link (NSRL) was 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. ^[2] 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.^[1]

The NSRL would connect

In 2017, a Harvard Kennedy School study estimated the cost of the NSRL at $4 to $6 billion (in 2025 dollars), based on Federal Transit Administration data and an analysis of comparable tunnel projects around the world.

MassDOT

study looked at four options with estimated costs ranging from $12 billion to $22 billion (in 2028 dollars).

As of 2024, the North-South Rail Link has not been pursued and is not in active development.

Historical connections

This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (January 2022) (Learn how and when to remove this message)

From 1872 to 1969, the freight-only

street running

connection between most of the south-side and north-side railroads, and served local customers and wharves in between.

From 1901 to 1938, the Atlantic Avenue Elevated provided direct passenger service past North and South Stations. The elevated trackage was not connected to any of the conventional railroad tracks.

Present connections

Public transit connects

In June 2018,

The 2018 MassDOT feasibility study analyzed four options. The costs, presented in 2028 dollars, include purchasing additional rolling stock, other required infrastructure improvements, and a 3.5% annual inflation. Presenters noted that a planned expansion of South Station would cost an estimated $4.7 billion, not including the purchase of rolling stock, electrifying the system, and renovating Tower 1.^[1]

Two options would run under the Central Artery (I-93), one option with two tracks and the other, more expensive, with four. The other two options, each with two tracks, would tunnel under downtown Boston several blocks west of the Artery. All the proposals connect the northern commuter rail lines with South Station and then to Back Bay and lines to the west. Only the four-track option would connect North Station with the Fairmount Line south of South Station. Under all the proposals, the Old Colony Lines would continue to terminate at the South Station surface platforms. The existing North Station and its surface platforms could be eliminated under all four options, making the area available for redevelopment.^[1]: 23

Central Artery four-track

The most ambitious option is the only one that includes a new Central station (or Union Station) near its midpoint, and the only one with a rail tunnel connection to the Fairmount Line. North Station would be underground near the present station. The line would be constructed using two 41 foot (12 m) TBM tunnels, 125 feet (38 m) deep, along with cut-and-cover in Fort Point Channel. Underground South Station would be built in Fort Point Channel, east of the surface station. Central station would connect to the Blue Line at Aquarium station. The Blue Line is currently the only MBTA rapid transit line with no direct connection to the commuter rail network.^[7] Estimated cost: $21.491 billion.^{[1] : 63}

Central Artery two-track

Same route as Central Artery four-track but has no Central station. Constructed using one 41 foot (12 m) TBM tunnel, 125 feet (38 m) deep, with cut-and-cover used in Fort Point Channel. Underground South Station would be built in Fort Point Channel, east of surface station. Estimated cost: $12.317 billion.^{[1] : 63}

South/Congress alignment

North Station would be entirely underground and moved several blocks south, to between State and Haymarket Streets; no Central station. Stacked tracks and platforms are incorporated within a single 51 foot (16 m) TBM bored tunnel, 115–130 feet (35–40 m) deep. Underground South Station would be north-west of surface station. Estimated cost: $13.181 billion.^{[1] : 63}

Pearl/Congress alignment

North Station would be entirely underground and moved several blocks south, to between State and Haymarket Streets; no Central station. Tracks would be in two 29 foot (8.8 m) TBM bored tunnels, 135–195 feet (41–59 m) deep. Underground South Station would be north of surface station. Estimated cost: $14.388 billion.^{[1] : 63}

Electrification

The tunnels would not be able to handle diesel locomotives and therefore would require the use of

The 2018 feasibility study modeled ridership in 2040 based on various scenarios. In regular service, the two-track options would increase all day boardings to 195,000 compared with 150,000 in the no-build scenario. Assuming an upgrade to all-day peak service, the two-track options would increase all day boardings to 225,000 compared with 195,000 with the South Station expansion.^[1]: 47 Overall, NSRL would increase commuter rail capacity, in terms of seats to downtown, by 25%.^[1]: 56

The feasibility study presentation also projected the distribution of destinations for commuters coming from the north in the morning.

Potential issues

The 2018 feasibility study identified several potential problems and risks with the NSRL project. During construction of the Back Bay tunnel portal, required under all options, the MBTA Worcester Line and Amtrak Lake Shore Limited service would have to terminate west of Back Bay station or possibly be rerouted via the Grand Junction Line into North Station. Also some or all Amtrak, Providence, Stoughton, and Franklin Line service would be rerouted via the Fairmount Line into South Station.^[1]

The proposal makes aggressive assumptions about improved passenger loading and unloading times and on how many trains can operate per hour in the tunnels. The proposed train frequency, 17 per hour per direction in the two-track options, is higher than the current Red Line train frequency, and exceeds what has been achieved to date on other systems that use the new positive train control systems required for heavy rail.^[1]: 41 To maintain the 17 trains/hour frequency, trains would have to arrive to enter the tunnel precisely as scheduled.^[1]: 40 However, new systems like Thameslink in London, UK, have shown that up to 24 trains per hour are possible on heavy rail.^[8]

With the NSRL, the MBTA commuter rail system would be highly dependent on the tunnel routes. Any disruption to those routes would affect the entire system.

There have been several prior proposals to link South Station and North Station by rail. A North-South Rail Link was included in the original Big Dig design, but was dropped by the Dukakis Administration.^[9] An earlier leading proposal, called the "Dorchester Avenue Alignment", is similar to the four-track Central Artery alignment in the 2018 study. It would dig two 41-foot-diameter (12 m) deep-bore tunnels beneath Boston, extending beyond the present rail yards north and south of the city. The tunnels would pass about 20 feet (6.1 m) beneath the I-90 extension, and would reach their maximum depth of 130 feet (40 m) at a possible Central Station and at North Station. Carrying a total of up to four tracks, the tunnels would have steep inclines. Trains entering or exiting the tunnels would climb or descend 3% grades, each nearly 1 mile (1.6 km) long.^[10]

Because the tunnels would continue well south of downtown, three portals would accommodate separate connections to

Pilings for a South Station Tower at South Station complicate a proposal to put the tunnels directly beneath the present South Station. Instead, the Dorchester Avenue Alignment proposal would move the tracks just east of South Station, and would build an underground facility about 100 feet (30 m) below the surface of the Fort Point Channel at the Summer Street crossing.^[11] Tracks at the underground South Station would have a 0.61% incline.

The new Central Station would connect with the

A 2003 DEIR/MIS assumes that about one-third of Amtrak trains to and from points south would be routed through the tunnel, stopping only at South Station, but with a new stop north of Boston at Anderson Regional Transportation Center in Woburn, Massachusetts. The Downeaster service from Maine and New Hampshire was assumed to stop at North Station only, with a direct connection to more southerly service at Anderson RTC rather than Boston. Thus, some operations would continue above ground at North Station and South Station, and all track and facilities would remain in place.^[12] The tunnels would not be equipped to handle diesel locomotives, which may not be suited to the planned steep grades and closely spaced stops; several Commuter Rail lines would necessitate electrification to safely and efficiently operate in the tunnels.

Route map

The map below depicts one of the most extensive proposals made to date. The 2018 feasibility study options do not include a link to the Old Colony and Greenbush lines. Only the four-track option includes a link to the Fairmont Line and a Central station. The surface North Station would be eliminated in two of the options and might not be kept in the other two.

Route map of the North–South Rail Link (Central Artery Four-track Alignment)

Legend Lowell Line and Amtrak Downeaster Fitchburg Line Haverhill Line Commuter Rail Maintenance Facility (MBTA employees only) Newburyport/Rockport Line Proposed route Charles River Orange Line Green Line North Station Green Line Orange Line Central Station Aquarium Blue Line Red Line South Station Framingham/Worcester Line & Amtrak Lake Shore Limited Fort Point Channel Amtrak NEC; Needham, Franklin/Foxboro, and Providence/Stoughton Lines Bass River Red Line Fairmount Line Old Colony Lines This diagram: view talk edit

Status

In May 2006, the Commonwealth of Massachusetts withdrew its sponsorship of the project due to its high capital cost (projected at several billion dollars, with wide variations depending on which option is chosen). Without matching local funds, the project was ineligible for federal funding, and was no longer listed as an approved project in state and Boston MPO capital plans. The April 2007 document Journey to 2030: Transportation Plan of the Boston Region Metropolitan Planning Organization said "the MPO feels that a study of the right-of-way requirements should be conducted for preservation of that right-of-way so as to not preclude this project's going forward in the future."^[13]

In December 2007, the Federal Railroad Administration was interested in funding this project if the Massachusetts Executive Office of Transportation was interested in sponsoring it.^[14] In August 2009, the project was brought back into the spotlight as a component of the New England transportation plan, a coordinated effort by the six New England states to improve rail transportation infrastructure by competing for the $8 billion allocated for high-speed rail in the American Recovery and Reinvestment Act of 2009.^[15]

In December 2011, former Governor

In June 2018, MassDOT released a North South Rail Link Feasibility Reassessment presentation that proposed several tunnel alternatives, described above.[1] The state began soliciting bids for the $2 million feasibility study, advocated for by the North-South Rail Link Working Group, in March 2017. The study did not identify a funding source for constructing the NSRL.^[6] On September 6, 2018, MassDOT released their draft feasibility reassessment report and asked for public comment by October 19.^[20]

Alternatives

As of 2018^[update], the MBTA and Amtrak use the