Re: North-South Rail Link
- Re: station location ... I think there is an expectation that being able to transfer from terminating surface trains to through-running tunnel trains @ NS & SS is important, so most plans/proposals have assumed at least underground stations serving each surface terminal.
That's certainly something I haven't been thinking about much, and depending on what service patterns we end up planning on having it might end up being somewhat important. On the other hand, if the Orange Line gets extended out to Reading, and the Lowell and Haverhill via Wildcat branches run into the NSRL, and if the Fitchburg Line also runs into the NSRL and if Newburyport / Rockport were to serve Sullivan (connection to Reading service) and Porter (transfer point for Fitchburg Line), the remaining question is how to transfer from Newburyport / Rockport to Lowell Line, and maybe some platforms could be constructed near where those routes intersect. (Or in the massive-build scenario with some Newburyport / Rockport trains serving Sullivan and Porter and others serving Airport, South Station, Back Bay, etc, maybe just use the underground South Station as the Newburyport / Rockport to Lowell Line transfer point.)
Also, right now we don't send Fairmount and Old Colony trains to Back Bay to continue to West Station because they'd have to cross over most of the Back Bay to South Station tracks at grade to do so; if a lot of the Back Bay trains were to disappear into the NSRL instead of going to the South Station surface platforms, and if there was a way to get from the Fairmount and Old Colony lines to the Worcester side Back Bay platforms without an at grade conflict with Providence side Back Bay to NSRL, that might allow some Fairmount and Old Colony trains to serve Back Bay and make Back Bay work better as a transfer station between more south side lines, along with giving those lines an Orange Line connection and possibly reducing the capacity crunch on the NSRL and South Station surface platforms.
I'm wondering if it might make sense to send all Providence-side-of-Back Bay trains through the NSRL, send Amtrak Inland Route traffic through the NSRL, keep Worcester Line peak direction commuter trains going to the South Station surface platforms, give the Fairmount Line 12 minute headways to the South Station surface platforms plus 12 minute peak direction headways to Back Bay / West Station, and also give peak direction JFK to Back Bay 12 minute headways, with the idea that each of five branches (Greenbush, Plymouth/Kingston, Cape Cod, Fall River, New Bedford) could get hourly service to Back Bay. (Worcester Line reverse peak trains would then be the extension of Old Colony and Fairmount's peak direction Back Bay service, and the Worcester Line trains at the South Station surface platforms would deadhead to a yard after arriving in the morning, and deadhead from a yard in the afternoon.)
- Routing: I think the Porter comparison is an apt one. A devils advocate might point to the persistent leaks at Porter Station as a cautionary tale - but theyre not really a deal-breaker for the Alewife extension either.
Hasn't Downtown Crossing also been known to leak in heavy rain? I think the point here is that any construction technique can be leaky if it's not done well.
Bottom line for me - I understand the practicality of sicking to the incumbent routing for the purposes of focused advocacy and streamlined execution
The whole mess in New York City with ARC cancellation followed by Gateway would seem to demonstrate that if you push for a lesser projected with weaker advocacy and then get an anti-infrastructure governor, the advocates are less upset about project cancellation, and then when you finally come back to do Gateway the right way, you're even further behind on the schedule.
- Gl from the north: I like the idea of a greenway routing crossing the channel to Courthouse. A related possibility is to route GL down NSRL to SS, then pull a 180 in the existing bus turnaround and use the SL tunnel to cross the channel. This is the antithesis of what F-fline likes to call the 'pretty parallel lines' fallacy: it would look sort of a bonkers on a map, but in terms of service timing and constructabiity, it might actually make sense
I'd been thinking that being able to have Green Line trains run from Aquarium to what is currently the South Station busway might be desireable if it means you could then continue those Green Line trains toward Dudley, but I'm under the impression that the Transitway at South Station is above I-93 whereas Central Station at Aquarium is expected to end up under I-93, so I'm not sure where you have the Green Line transition from below I-93 to above I-93, and I'm also skeptical it's really a compelling enough service pattern to justify the tunneling cost. But trying to reserve space for it if it's feasible might well be worthwhile.