Boston's plan for a sub-city rail link
Boston's plan for a sub-city rail link Nov 2010
Shani Wallis, TunnelTalk
Just as the remnants of Boston's elevated Central artery come down - leaving in its place a tremendous feeling of openness with light now streaming into offices and buildings along the corridors and the noise and fumes of the six to eight lane traffic now confined to underground - there are concerted moves a foot to reinstate an element of construction that was initially central to the original infrastructure master plan. Concurrent with relocation underground of the I-93 Central Artery highway, there was to be within the same right of way a fixed link connection between the city's North and South station railway terminals.
The stations lie just 1 mile (1.6km) apart and to the north and south of the central business district. Existing as a result of historic development of Massachusetts railroads and the constraints of local topography and use, both are major intercity and interstate terminal stations. Both also host operation of hundreds of peak hour train services for thousands of city visitors and commuters each day.
From the north or south station terminal, commuters and travellers transfer onto the city's subway system and into journeys into city centre offices or across town to pick up onward train services.
Fig 1. A North and South Station link would integrate Boston's rail services

Fig 1. A North and South Station link would integrate Boston's rail services

For the sake of closing the 1 mile gap, the city's existing public transit services are increasingly crowded and congested. Daily ridership on commuter services has grown from total 75,000 in 1990 to about 126,000 in 2000 with a projected increase to some 244,600 by 2025. Traffic on the city's four subway lines is expected to increase commensurately, particularly at peak times. It is reported also that daily vehicle miles travelled on the city's regional highways will have increased by 139% from 1995 to 2025 to a total 149.1 million miles/day.
The advantages of a proposed north south rail link (NSRL) speak almost for themselves. Through-train services would ease significantly congestion on city streets, peak time crowding on the subway system, and would connect more effectively and efficiently the rail networks of new England with those of the northeast and the rest of the country (Fig 1). Project proponents say that the 1-mile break in rail services in Boston is the most detrimental missing link in the country's national transportation network and that doing something to rectify the situation should be a regionaland national priority.
Where did it go?
A link between the rail terminals was first studied in 1909 but realisation came closest in 1972 when a two-track rail tunnel connection was proposed as part of the central artery reconstruction program. Sources involved with planning of the Central Artery/Tunnel (CA/T) project in Boston at the time confirm that a concurrent rail link was part of the master plan up to the final project funding negotiations. CA/T is the last major project completed under the US Interstate defence highways across the country were built as a matter of national security and funded 90% by federal tax dollars and 10% by local state government contributions.
This legislation has since been superseded by the Intermodal Surface Transportation Efficiently Act (ISTEA) of 1991 and its 1998 update the Transportation Equity Act for the 21st Century (TEA-21). Both are designed to promote development of economic, efficient and environmentally sound intermodal transportation systems. Under the new legislation a combined CA/T+NSRL project could have been feasible. Under previous legislation the combination proved too complex and the rail link was dropped, allegedly to secure the 90/10 federal interstate Highway funding before the deal was no longer available.
In late 1993, with the highway only CA/T project approved and in construction, the US congress directed the National Railroad Passenger Corporation (Amtrak) to undertake a North South Rail link study to study to identify the operational requirements for both intercity and commuter rail needs; preserve the option of constructing a link within the Central Artery corridor at a later date; and identify potential environmental impacts from rail link alternatives.
Amtrak entered into an agreement with the Massachusetts Executive Office of Transportation and Construction with MBTA(the Massachusetts Bay Transportation Authority) managing the study in collaboration with the Massachusetts Highway Department and with the FTA (Federal Transit Administration) co-operating as the study's lead federal agency.
In June 2003, the task force produced its Major Investment Study/Draft Environment Impact Report (MIS/DIER). The study considers several options including two that require no new construction. One a dedicated shuttle bus service between the two stations and the other an increase in peak hour Orange Line Subway services that connect North Station to the Back Bay Station, southeast of south station.
Of the new-build options, all are underground and utilize much of the Central Artery corridor right-of-way to cross the city center. Having lost the opportunity to build the rail facility into the bottom of the slurry-wall supported open cut excavations of the I-93 CA tunnels, the study's proposed rail link options are based on deep bored tunnels. These would start on the east side of the depressed highway at south station and pass under the highway to the west side of the alignment at North Station. This provides a physical separation between the two; preserves the option of constructing the link within CA/T corridor right-of-way; and allows the CA/T and the link projects to advance independently.
Deep Tunnel Designs
The tunnel options are all about 3-miles long portal to portal. Beyond the middle CA/T alignment, tunnel options would extend south to South Station to a portal and connection to surface track infrastructure at Back Bay and another in the South Bay rail maintenance yard. Beyond North Station, the alignment continues in bored tunnel under the Charles River to another two portals in the Boston Engine Terminal area connecting to the Fitchburg and to the Lowell, Haverhill and Rockport/Ipswich Lines. The study considers a link capacity of two or four tracks built into either one or two double track tunnels of 41ft (12.5m)-diameter. The study also considers the possibility of adding a third Central Station in the vicinity of State Street and connected to the subway. New North and South Station facilities would be located beneath the existing surface station buildings and would use the same head houses for passengers access. Portal areas are located within existing railroad right-of-ways. This would limit construction impact on city life and allow spoil removal and materials supply by rail rather than road. Excavation could progress from the north portals where staging space is available. Another option would be to use public land formerly used by the US Post Office to advance running tunnels north and south from a South Station cavern mined beneath the existing station tracks and using barges and rail to haul muck.
Fig 2. The 3-mile rail tunnel in Boston's underground environment

Fig 2. The 3-mile rail tunnel in Boston's underground environment

As a draft EIR to meet state environmental regulations, the study does not enter into detailed investigation of geological conditions or the impact of proposed tunnel excavation on adjacent infrastructure but it does indicate how the proposed tunnel could be built into Boston's increasingly crowded underground environment (Fig 2). It also proposes an alternative Dorchester Avenue alignment at South Station to provide an underground station option to the east, along the western edge of Fort Point Channel.
Operational considerations studied in the DIER estimate that as many as 54350 new transit trips/day would be added to the system for the optimal four track option. For the same optimal configuration, it states that subway transit trips in the downtown area would be reduced by 5.2% and that daily trip on local buses would fall by 2.6%. Daily commuter rail trips are anticipated to increase by 82,700 or 33.8% as passengers transfer from other transportation modes to the more convenient commuter rail services. It further estimates a 1 million miles/day or 0.7% reduction in regional vehicle miles travelled /day resulting in substantial reduction in air pollution emissions.
Time and costs
It is suggested that a preferred deep bored tunnel alternative would take between six and eight years to excavate, depending on construction techniques used for building the stations and the availability of construction access points. The cost is estimated at $3.9 billion for the 2-track.2-station option (in 2002 study dollars) to $6.5 billion for the optimal 4-track.3-station options. At an assumed start of operations date in 2014 and an inflation rate of 3.5%, the turnout cost is estimated at $ 10.4 million to $12.5 million.
The study does not explain in detail how the figures are compiled but is does examine cash flow and project development expenditure. An estimated $8.7 billion is required for a 20-year development of the optimal option from the initial design, through construction and into the first nine years of operation and debt servicing, including necessary equipment and all associated costs.
What now?
The executive summary of the June 2003 MIS/DEIR recommends that the study be distributed to interested parties and governmental agencies to provide "a framework of decision making on a major transportation investment". It also urges "establishment of a project sponsoring organisation with the ability to provide a source of revenue, of significant size and stability, to support the debt service that would be required to construct the project. It is "unrealistic", the study states "to expect the project could be developed by either the MBTA or Amtrak using traditional federal and state transportation funding sources given the projected Commonwealth of Massachusetts fiscal year 2004 budget shortfall and the intense competition for federal transit funds." Along with the mountains of technical, logistical and funding issues to be resolved, the proposal faces the wider highly sensitive issue of asking the citizens of Boston to accept the impact of another mega-project construction program in the heart of their city so soon after the Central Artery 'Big Dig'.

Last piece of the elevated Artery leaves Boston's skyline

The issue is not underestimated but there are influential supporters of the project including dormer Governor Dukakis of Massachusetts under whose administration the Dig Big advanced into construction. The project is however already entangled in political controversy. In September 2003, the Metropolitan Planning Organisation (MPO) of current Governor Romney's administration voted to exclude mention of the project in the state's long-range 2004-2015 transportation plan. It also requested that the FTA (Federal Transit Administration) with hold publishing the project's federal Environmental Impact Statement because, it is said, of jurisdictional issues regarding public and private participation in federal highway, railway and transit funding. With the long range transportation plan submitted to congress for federal approval, the exclusion prompted state representative signatures on a letter to Governor Romney urging that consideration of the project be included. The letter states that long range plans in the MPO "continue to emphasize expansion of the roadway system", but that "no highway expansion project relieves traffic; it simply encourages more". The NSRL it states would remove "an estimated 50,000 cars/day from Boston's highway system". In a letter to Richard Doyle, Regional Administrator of the FTA, Massachusetts Congressman Stephen lynch said that his interpretation of the National Environmental Policy Act (NEPA) (under which study was advanced) "requires that the FTA port circulate its related DIEs report for general comment". He continues. "Considering the time, effort and taxpayer dollars expended" he hopes the FTA "will reconsider and release the study".
Latest reports confirm that the project now has an oblique reference in the current and midterm DIER capital works program for the state but still no local or federal direction on possible sources of funding. As the next move for the project's political chess game is awaited, there is activity behind the scenes to discuss its potential development. At a closed meeting in Boston in April ,convened by the Sierra Club as strong supporters of the project ,high profile industry leaders, public company managers and officials ,mega project financial advisors and directors of national rail projects including the Alameda rail project in Los Angeles and the Capitol Corridor Joint Powers Authority in Oakland ,discussed options for developing non-traditional sources of project finance. As well as private capital options ,it was suggested that application could be made for federal Highway Agency funds under TEA-21 regulations and that the project would assist future environmental management of the regions highways .Non-traditional methods of funding, explained proponents, are methods by which nearly all transportation projects were funded prior to the introduction of the growing reliance federal subsidy programs of the current 'traditional' sources introduced in the 1340's to jump start the domestic economy after WWII.
Precedent for using both private and alternative federal funding sources has already been set. In San Francisco, revenues from atoll increase on Bay Area interstate highway bridges will be used to undertake necessary seismic retrofit Bart's Trans-Bay mass transit immersed tube facility, recognisingthat any closure of the trans-bay tube would seriously impact traffic on already congested Bay Area highways. In Dallas, Texas state legislation is being amended to allow potential use of private capital to build the increase capacity tunnels for the Interstate LBJ Freeway. In Virginia, a 25 % private enterprise source of funding is vital to construction under a design-build concession to extend Washington DC metro services to Dulles Airport and beyond.
Interpretation of federal, state and local legislation to enable private enterprise marketing to supplement public funding is increasingly beingexplored. For Boston's North South Rail Link and other environmentally progressive projects around the country, such reinterpretation may be the only feasible way to serve public as well as private interests.

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