jrc520 wrote:It doesn't look like it. I haven't looked at the area in a few years, but from what I can remember, it's already pretty tight.
http://maps.google.com/maps?hl=&q=&ie=U ... 7&t=h&z=17
You'd have to underpass, but it's doable. The ROW once it underpasses I-93 has about 3x the dead space around it as the current tracks occupy. The side where the Cabot tracks go has a couple tree-filled medians on the opposite end. You can see on the satellite view that the Old Colony and Red Line yard tracks flyover/under with a crude box tunnel. Something like that but longer would do the trick nicely enough. It's not like this area isn't very easily reconfigurable. I want to see the Indigo become a Red Line-class
heavy-rail line when the N-S link is built...interoperable with the Red but not part of it. The Link can either go a 2-track or 4-track configuration. 2 is the slimmer alternative, wouldn't have the Central Station, and would prioritize the intercity lines as thru service while others continue to terminate north/southside. 4-track is the luxurious one with Central Station and nearly every line having some thru service.
Frankly, that's unnecessary. Nobody's going Needham-Fitchburg. And few people absolutely HAVE to have a Blue Line transfer in walking distance of two CR terminals, especially one that's going to have shorter platforms that can't handle max-size intercity trains. And the worst expense bloat is going to be doing all 3 southside portals to the NEC/Worcester, Fairmount, and Old Colony.
Simplify. Make it a 2-track straight pass-through CR tunnel between terminals concentrated on thru service on the NEC to/from NH and Maine, and the B&A from points west since nearly all long-distance passengers go those ways. And then make the OTHER two tracks rapid-transit. Build a much shorter, steeper, and much less-expensive subway incline from Fairmount/Indigo. Continue north with the Aquarium/Blue and NS connector as a new subway line. And then take over the Green Line Medford branch on the northside with heavy-rail. Go as the next phase with an extension to Anderson RTC as the NH Main ROW gets rebuilt as HSR, put all local stops on rapid-transit, and net a 128-to-128 subway line. Free up the "new" NEC to speed through Boston metro with no local stops at all besides Westwood/128, Back Bay, SS, NS, and Anderson (can even permanently get rid of Hyde Park since nearby Fairmount is going to be a real subway stop). Make a new rapid-transit yard at the empty Readville and share fleets with Red. Put short-turns at North Station and South to run high-frequency service from the termini, and also run Braintree-North Station short-turns via the Red Line yard tracks as special rush-hour service.