Apologies for ignorance, but what is AMA (American Medical Association?) compliant mean and how is it different from ADA compliant?
No, that's me 'typing stupidly!'
It was late at night and I was tired. I meant to say ADA.
I agree with you re Cambridgeport. So your thought, in this scenario, is that the Blue Line would parallel the new Beacon Street tunnel, but running express, right? Okay, I can see that working. On the other hand, Beacon Street looks pretty wide. Why not quad track a Beacon Street subway, and run BL express down the middle? (Or along the sides, whatever.)
(I can, obviously, see many reasons why a quad tracked Beacon Street subway wouldn't fly, but I'm curious as to your reasons.)
The curve to get to Beacon Street from Charles/MGH would follow the Embankment Road into Storrow Drive anyway, and there's about 300 feet of space between Beacon and Storrow. You could make the argument to quad-track Beacon Street, but it feels simpler (if likely more expensive) to have two double-track tunnels instead. Plus, I'm not sure that it'd be all that easy to go back and modify the tunnel later, meaning the Green and Blue segments would be a 'both or neither' proposition, and you'd be locked into a Kenmore alignment for the Blue Line. That would let you convert two branches of it into Heavy Rail, but would you really need to?
For that matter, could you?
Omaja had a similar comment on service complications like that on a crazy pitch of mine over in the other thread. I get where he's coming from, and I think I understand where you're coming from, but I'm not quite sold. How would the OL and HRGL sharing tracks between two stations be much different than the current arrangement of the Red Line? You have two services with different destinations that will need to be dispatched differently that happen to be on the same tracks for a bit.
Or would it just be too complicated because everything happens in such a short distance?
The Red Line branches just before JFK/UMass. JFK/UMass and all stations south of it are drops in the bucket compared to what comes north of it. In this way, the MBTA can 'afford' to split headways 50/50, because having 10 minute peak service on either branch means 5 minute headways through South Station - Harvard. Hell, if you had a world-class agency full of extremely competent people at the helm, you could swing for 5 minute peak headways on either branch and that would mean a train is traveling between the busiest section of what I believe is the busiest line every
150 seconds. Assume you stop the trains for 30 seconds each, that's an opportunity to board coming every 2 minutes.
But we both know that 'world-class' is not an accurate description of the T.
So adopting the 'Red Line' school of thinking to Orange/Green dispatching through Haymarket/North Station means you have to do one of three things.
You
could adopt the 'JFK/UMass' style set up, with two island platforms serving four tracks, but this would probably end with two tracks being dedicated Orange Line and two tracks dedicated Green Line. At that point, it's shared trackage in name only. (It could also end with two tracks dedicated inbound and two tracks dedicated outbound, which is a better setup.)
Or, you
could go with an arrangement like Savin Hill, where all trains pass through but only two of the tracks have a platform to stop at. That would mean 50% of your trains are expressing through Haymarket and/or North Station and that's going to go over like a lead balloon.
I like. I think I would go with Alewife over Fresh Pond, though. Create two routes into the cities from there. And I wouldn't want a new Park-n-Ride built at Fresh Pond. (You could also hit up one of the heaviest used stations on the T instead: Harvard.)
I like redirecting LRT east of the Orange Line. I think LRT along Surface Road is a perfectly reasonable idea. How would you connect it to the rest of the Green Line LRT network, if at all?
I went with Fresh Pond because the line already crosses Porter Square. Sending it over to Alewife means you're doubling service between Alewife and Porter for, frankly, zero benefit - unless there's a huge unspoken community of people who are demanding a
single seat ride from Alewife to North Station for whom transferring at Porter is a deal-breaker that I don't know about. A Fresh Pond extension is also on a ROW that has decayed enough that we could rip it out and drop something new in, yet has not been abutted enough (up to Huron Ave, anyway) that we couldn't squeeze two tracks in if we did rip out the one that's there now.
Mount Auburn Cemetery complicates matters some, otherwise it'd be an easy and straight shot on that very same ROW down to Watertown Mall / Arsenal Mall, and on into Watertown itself, serving a lot of ring capacity. If we did that, though, I'd probably keep the Fresh Pond / Porter branch of GLX as LRT, having all HRT go up to West Medford.
Run the LRV lines on the surface on Causeway Street and Nashua Street, and it would be very easy to connect with the Green Line as it emerges from the portal next to Nashua Street. Red lines indicate new surface LRV track:
You'd lose North Station if you did this. I'd create a new incline between Valenti and Market Streets and have the trains turn to reach the Greenway for their first new stop at North Street. (Then on to Aquarium Station, High Street - Rowes Wharf, and South Station. It would be designated the NS Branch or Greenway Shuttle, and would be where we sent all our 2-car consists to die.)
The Oak Square and BC lines run all the way through to Mattapan, while the C line runs down to Arborway. The idea was that the LRT lines would act as intra-neighborhood transit corridors, primarily being used for short trips, and secondarily as feeder services into the HRT Green, Orange, Red and EMU Indigo Lines. 
