Rail link costs could rival Big Dig
Buried North, South Station connection could hit $21B
The cheapest version of a rail link between North and South stations would run about $12.3 billion, and a more extensive version could cost about $21.5 billion, according to a draft study by the MBTA.
The T’s analysis, pursued with the consultant Arup, dwarfs the figures in a study publicized last summer by Harvard Kennedy School students estimating the rail link would cost between $4 billion and $6 billion.
Burying commuter rail trains and Amtrak lines deep beneath downtown Boston would approach the tab for demolishing the Central Artery overpasses and building the Big Dig tunnels. In 2012, state officials tallied up the Big Dig costs to $24.3 billion.
MBTA General Manager Luis Ramirez has so far reserved judgment on whether the North-South Rail Link would be a worthwhile pursuit, telling reporters he is looking forward to seeing the results of a study looking at the future of the commuter rail.
The study, which will be the subject of a public meeting Thursday and publicized in draft form in early July, did not make any recommendations on whether to invest in the rail link. Former Govs. Michael Dukakis and William Weld have advocated linking the two terminals that serve points north and south of Boston.
Dukakis urged the MBTA Fiscal and Management Control Board to be skeptical of the cost estimates, which he said are out of line with other tunnel-boring projects.
“I would simply urge you to take a very good look at the cost figures you’ve been getting. They bear no relation to reality,” Dukakis said.
New stations along the connection would be buried deeper below ground than even the most subterranean MBTA station — Porter Square in Cambridge — and the logistics of digging the tunnel would tie up train traffic along the Worcester line, according to Scott Hamwey, a state transportation planner who presented the findings to reporters.
The new stations would be 115195 feet deep, according to the study. Porter Square is 105 feet deep.
The tunnels would be dug by a boring machine, which would create “a little bit of a mess where you start the project,” Hamwey said. The machine would be buried in the relatively tight right-of-way between Back Bay and South Station where train lines run alongside the Massachusetts Turnpike.
The T could probably keep one line open along that rightof-way, but service to Worcester would likely terminate at Yawkey Station, and Amtrak service would need to be rerouted onto the Fairmount Line, according to Hamwey.