Why short-turn at all? Cutting off direct access to downtown like that strikes me as a pointlessly spiteful move towards B/C/E line riders. One of the main goals here should be to preserve access to the hub of the system by those branches, whether that's along a Riverbank tunnel or through the existing tunnels.
I assure you, my intentions are anything but spiteful. I disagree regarding the main goals here: it seems to me that the most important goal is to ensure that the most people possible have reasonable access to speedy and reliable transportation, whichever form that might take.
The short-turns allow the rest of the system to be streamlined and simplified, permitting longer trainsets, better headways and faster travel times. The short-turns also permit better headways on the trolley lines themselves, since they are no longer constrained by capacity in the Central Subway. The short-turn design also contains delays rather than permitting them to propagate throughout the system.
The drawback of short-turns, of course, is that riders have to transfer. And transfers suck because you have to stand and wait for a few minutes, which adds travel time to your trip.
On the other hand, if these short-turns increase the reliability of both components and the speed of one, then you don't have to worry about the Green Line having a crazy delay, and– I'll bet– you won't mind waiting 3 or 4 minutes for a cross-platform transfer.
Also, using HRT as a spine with short-turns allows you to create more branch lines than you could if all of those branches fed into the central subway. As it is now, we're probably limited to six, maybe seven branch lines in the central subway. With a spine-and-shuttle system, we're limited primarily by the capacity of the trains themselves, not the tunnels they're in.
Part of the problem with the system now is that
the current branches exclude other corridors in Metro Boston from getting service. Northern Brookline was lucky and managed to hold on to three, count 'em,
three direct rail links into downtown Boston, while
- Brighton
- Jamaica Plain
- the South End
- a good chunk of Dorchester
- Mattapan
- South Boston
- most of Charlestown
- Everett
- Somerville and
- Chelsea
all lost theirs.
If we can run rail service directly from downtown to all of those communities, then, great, I'm all for that. But from what I know and have learned, we are not likely to increase subway capacity much at all downtown, partly because it is simply no longer feasible to dig downtown (due, in no small part, to the Big Dig).
If some riders in Brookline lose a one-seat ride into downtown (bearing in mind that the Riverside line remains, and that the Watertown line replaces the B for a mile and parallels it less than 2000 feet away for more than another mile), and the result is a two-seat rail ride for residents of JP, the South End, Dorchester, South Boston, Chelsea, Needham, parts of Brookline, Somerville, Cambridge, and a one-seat rail ride for lucky folks in Allston, Brighton, Brookline, Newton, Somerville and Medford, that's okay with me. More people served? Check. More reliable service? Check. Faster service? Check. Yep. It's okay with me.
As for the D, I think converting it is more trouble than it's worth in the end - and the payoff for the conversion is the lowest among all possible lines there. (In order from worst to best payoff, it's probably D - C - Tie E/B. Fitting that the two best choices are also the two most difficult.)
I agree with your assessment for the most part (I think the E probably beats out the B by a hair, because it would be comparatively easy to do [few hills and curves, assuming we terminate at Riverway or Brookline Village]), but I disagree that with your conclusion that just because the D is the worst payoff, it shouldn't be done (particularly if you combined it with a Huntington Ave subway, which I realize is moving the goal-posts a bit, and I apologize for that).
We don't need to tie a restored A in with a Heavy Rail Conversion, either. The A can work fine as a light rail route.
I agree that the A itself doesn't need HRT. However, the A would be one of the better ways to get rapid transit out to Waltham, a major urban satellite of Boston that's currently without any form of rapid transit. (You could run DMU's out the Fitchburg line, but that's less direct, and wouldn't link Waltham Center with a series of high density areas: Watertown, Brighton, Allston and Brookline.) And using the A as a spine puts HRT through a relatively high-density neighborhood of Boston, roughly equidistant to the two nearest other HRT spines (the Red and Riverside Lines), and serves as a good centralized location for potential shuttles to link up to. (Potential corridors: Commonwealth, Chestnut Hill Ave-Market Street-Western Ave, Harvard Ave [north-south], Warren-Winchester-Longwood [crosstown] and anything coming out of Watertown Square, including Mt. Auburn St-Harvard Sq.) And if the A used the MassPike alternative instead (arguably a better route, for reasons I outlined in my original post), then the original A Line alignment becomes another potential shuttle.
Off the shelf LRT can't handle that turn, either, which is one of the contributing factors to why all our Green Line rolling stock needs to be massively over-customized. We could fix this right now with some minor modifications to the curve - and I'm talking seriously minor, on the order of about a foot of targeted shaving down to the curve geometry itself.
Cool, I never knew that. Thanks.
There's absolutely no need to bypass Boylston if we just correct the unfavorable geometry, something that would cost us pennies when compared to a full bypass. That doesn't mean we shouldn't dig a tunnel from Boylston to South Station anyway - the angle of approach lines up perfectly with the bus platform in South Station Under and the bus tunnels out to the Seaport - World Trade Center Station, but why stop there? A little more digging (or, god forbid, street running) and you could bring the Green Line up to the Marine Industrial Park and the Design Center, then turn down Summer Street to City Point and right on over E 1st to Marine Park at Farragut Road - or, if you're feeling saucy, Fort Independence/Castle Island.
I agree, although I do think it's important that the Green Line intersect the Blue at some point– you're proposing the GL to Southie
in addition to the maintenance of the current Tremont Street subway, right?
This, by the way, is really only possible if you don't convert the subway between Kenmore and Boylston, which is one of the leading reasons why we should route any heavy rail Green Line along the Riverbank Subway instead.
Unless you run the Southie train as a shuttle into South Station, possibly continuing up the Greenway to Haymarket or North Station via Commercial Street, or run it as a subway up Congress Street to State or Haymarket (though I grant that the latter is probably more complicated than it's worth). I agree that running the Southie train as a shuttle is less desirable than direct Kenmore-City Point service, but I don't think it's less possible with a converted Green Line.
(But I agree that that routing is a good argument for maintaining LRT in the Boylston Street Subway.)
We could easily tunnel 4 tracks under Storrow. As long as it's there, why not? Tunneling doesn't necessarily preclude removing Storrow later, either, but if we take part of that ROW for surface-running tracks, it's going to be significantly harder to ever get rid of Diet Storrow without axing the tracks too - to say nothing about how much worse the mess that's going on with the Bowker Overpass gets if you start trying to run tracks right through it. It'd really turn out to be a textbook lesson in "money savers" that end up costing you more money than the expensive thing you didn't want to do.
I admit that what F-Line is saying here goes a bit over my head, but, according to him
here, the only option is to build on the Storrow Roadbed itself (I think). I'm theoretically for slimming down Storrow and putting tracks down in place of the roads, but I think you're right, we'd have a hard time getting rid of Storrow altogether. Hence my proposal for street-running trolleys in the Back Bay. No need to fuss with all of that landfill, and leaves open the possibility of running the Blue Line down half of Storrow separately.
Of course, if I'm wrong, and we can dig underneath Storrow, then yeah, that's a better idea. But I was trying to come up with a creative solution to the Storrow-tunnelling-problem-that-prevents-us-from-doing-as-big-a-Riverbank-subway-as-we-want problem.
The problem there is going to be yard access for the LRTs, I think. That's a lot of shuttle lines, and unless you maintain non-revenue track for light rail in the upgraded GL tunnel, you can't move the rolling stock. Not to mention that you're cutting maintenance facilities for the light rail system down to only Boston College and Reservoir, which I would bet aren't nearly enough. Maintaining the Riverside Yard is a primary reason why I don't expect the T to ever upgrade the D Branch.
You bring up good concerns. A couple of responses:
-ideally, HRT GL would use catenary wire on the surface. If I understand correctly, regulations prevent HRV and LRV from running on the same tracks at the same time. This is probably a good thing, though it's a shame in some ways and has ruined some of my more exciting ideas.
So that leaves us limited to night moves, which, I have to admit, are probably not going to be sufficient. But still, in theory, the shuttle LRVs travel along catenary-powered main-line HRT track to Riverside Yard at night as needed.
-on the other hand, it is indeed a lot of shuttle lines, but they only cumulatively add up to 14.2 miles of route. (At least, the ones I outlined specifically in the map.) No single one exceeds 3 miles in length, except for the Needham, which is a bit more than 4. The current GL system totals more than 23 miles of route. How much of the current rolling stock would you need for that? Would that make the infrequent night move more manageable? (On the other other hand, if we start adding on other shuttles, eg. Mattapan [4 miles], Harvard-Longwood [4 miles], Mt. Auburn [3.5 miles] and various things in Cambridge, Somerville, Everett and Chelsea, then we run into a bigger problem, and would probably need to build a couple of new yards [even though the GLX Yard could be thrown into the mix that way].)
-this concern would also be a good reason to support a MassPike alignment of an HRT A Line; a trolley line could run from Allston Village to Newton Corner and have a non-revenue surface track running to a resurrected Watertown Yard (with non-revenue connector tracks running down Warren Street to connect to Commonwealth). .3 miles down Galen, then turn on Water and enter the yard from the south.
I'm not convinced that the curve is an insurmountable challenge. The Chicago "L" has tighter turns, though the trains creep through them and the hill probably makes things worse. How about re-routing the HRT B-Line down Brainerd St? The "New A" covers the north side of Comm. Ave, straight shot to Packard's Corner under commercial parking lots and the road never curves, plus less traffic disruption if you cut-and-cover. It would suck for the neighborhood, though.
Good point about the El; I've wondered how they handle those curves. The creeping doesn't sound desirable though. :/
I'm intrigued by B via Brainerd in tandem with a New A to the north, though I wonder what you would do after Brainerd becomes Corey; go all the way until you hit Beacon? Or hook a sharp turn on Washington to get back to Commonwealth?
I still think the best option for Heavy Rail Green is a Beacon St. Subway replacing the C Branch. I would actually run it over to BC since it would be easier to turn the larger trains there than at Reservoir and retain the Reservoir Yard for LRT by running non-revenue B Line trains down from a terminus at Chestnut Hill Ave.
My issue with this is that the C works best of all the streetcar branches: straightaway, walkable neighborhood, not too long. And I'm not convinced Beacon has the density to warrant a full subway. You get BC, but you miss BU. And lastly, there's nowhere for it to expand later. I've proposed running the Blue up Chestnut Hill Ave into Brighton, but still, after that it becomes a matter a diminishing returns because anywhere you go after that will have such a circuitous route into downtown. (Though you could run it over to Harvard, as a sort of crosstown line.)
We're also forgetting that many CTPs for the Green Line include a Huntington Ave. Subway that would connect to the D at Brookline Village and replacing the E, so the D and E lines might be spoken for anyway. Also, any GL upgrade using a Riverfront Subway really should be seen as an extension of the Blue Line, since presumably that's what it would be...
This, especially that second part. Unless folks decide to tunnel under Beacon east of Charles, stopping at "Park Street North/West" and then ending somewhere around Gov't Center/State-ish. That could be messy, though.
In fact, here's my proposal. Extend the Blue Line under Beacon St. all the way from the Hatch Shell to Boston College. Restored A and truncated B use current tunnel, with A going to Union Square or Porter and B to West Medford. Riverside, Needham Junction and Franklin Park go under Huntington Ave, use F-Line's NEC concept to get to South Station and access the Silver Line tunnel, and end up in South Boston somewhere.
What's your envisioned route from Franklin Park? And while Newton and Needham folks would be able to transfer to the Blue at Reservoir, I worry about everyone else to the east of that needing to transfer to either the Red or the Orange to get to the Blue. What's your thought?
Whew. I'm going to go to bed now.
