Crazy Transit Pitches

[Riverside]

^Slicing the Kenmordian knot, as it were.

Yeah, that's the general idea. By adjusting the trunk of the Green Line to the south, Longwood becomes a radial destination. That opens up a lot more options for connectivity, especially because you can then layer circumferential connections on top of that. Moreover, using radial service solves some of the problems caused at the eastern ends of the B, C, and D branches: St Mary's St is just a little too far to provide a good conncetion at Audubon Square, but if the C turns southeast toward Longwood anyway, you have an easy transfer at Fenway station itself. The story's a little more complicated on Commonwealth, but the idea is similar.

I mean, looking at the OnTheMap job numbers really is startling:

Huge employment center in Longwood, the edge of a huge employment center in Back Bay, with a modest concentration at Boston University. Practically an employment cavity around Kenmore Square by comparison.

The population maps aren't as pretty visually but:

And from the City of Boston:

And Bostonography's map:

The two tracts immediately north and south of Kenmore Square see lower population density; the walkable neighborhood is bounded to the north by the Charles, to the east by Charlesgate, and to the South by the railroad tracks, the Mass Pike, and then Fenway Park.

Compared to all the surrounding neighborhoods, Kenmore Square is neither a major center of population or employment. The Fenway-Kenmore neighborhood to the south -- whose walkable access to Kenmore Square is substantially limited by the aforementioned barriers -- sees higher density, a higher population, and closer proximity to jobs in Longwood.

All other things being equal, why wouldn't we try to anchor our rapid transit network to Longwood?

~~~

There are some downsides. The biggest probably is cutting off Beacon St from its direct connection to Kenmore Square (if you choose to reroute the C to Longwood, which I should note you don't have to). This can be ameliorated with a bus route, potentially continuing on from Kenmore to Copley via Comm Ave, Mass Ave and Huntington (similar to today's 55).

Likewise, traveling via Park Dr etc does add additional traffic lights and other slowdowns. Some of these can be ameliorated with good planning (organization before electronics before concrete), but probably there will always be some speed penalty compared to running in a tunnel.

We would also need to modify plans for an extended Huntington Subway, and would need to maintain a portal somewhere near the current one. Huntington is wide enough that this is likely doable, but it does complicate things.

Finally, it does have to be said that -- even with all this -- Longwood still remains indirectly served: to the south along Huntington, to the northeast along Fenway, and to the northwest along the Highland Branch. The heart of Longwood remains accessible only by foot, bus, or auto. This is germane because (in my opinion) the obvious alternative to LRT via Fenway is BRT via Longwood Ave -- perhaps a transit mall of some sort. This would serve Longwood centrally, but relegates it again to circumferential service...

...unless you take the Bus Network Redesign approach, and build a sub-network radiating out from Longwood Medical Area across the region. I think this is the more realistic approach, and frankly if done right it could certainly be a very strong proposal.

Still: being able to string together Harvard, West Station, BU, LMA, Prudential, Back Bay, South Station, and the Seaport (and Charlie-willing someday the airport) on a single line is very tempting. (And based on my quick math, would actually provide a slightly shorter route between South Station and Harvard, believe it or not -- and certainly a shorter one between Back Bay and Harvard.) So, even if you don't reroute the C via Longwood, you could still get a lot of mileage out of an east-west Harvard-LMA-Seaport and north-south Kendall-LMA-Ruggles pairing. Running via Fenway might be slightly less useful for Longwood specifically, but could enable much larger change across the system.

~~~

For fun, here's a back-of-the-napkin sketch of what service patterns might look like with a reroute & connection via LMA:

• Harvard-Kenmore-Park: 10 tph (6 min)
• Harvard-LMA-Seaport: 12 tph (5 min)
• Oak Square-Kenmore-Park: 6 tph (10 min)
  • plus 57 bus Watertown-Kenmore every 10 min, for cumulative service every 5 min, like today's 57/57A split
• Commonwealth-Kenmore-Park: 10 tph (6 min)
• Beacon-LMA-Park-points north: 10 tph (6 min)
• Riverside-LMA-Park-points north: 7.5 tph (8 min)
• Needham-Kenmore-Park: 6 tph (10 min)
• Heath/points south-LMA-Seaport: 10 tph (6 min)
• Nubian-Park-points north: 15 tph (4 min)
• Kendall/points north-BU-LMA-Ruggles/points south: 10 tph (6 min)

(To use terminology I've used elsewhere, we can call Seaport routes "Aqua Line" branches, the Kenmore-Park trains "Emerald Line", and the through-running routes to points north "Green Line".)

You have lots of flexibility here: send Beacon trains to the Seaport instead, run Oak trains via Huntington instead of Kenmore, use the Kenmore Loop to short-turn some trains, etc etc.

 

[Riverside]

On a different note, let me toss this Crazy Transit Pitch grenade out into the ether before going to bed:

Convert the Southwest Corridor and Haymarket North Orange Line tracks to mainline tracks running layered services that maintain existing frequencies and are connected via the NSRL with a stop at Central Station. Free up the Washington Street Subway for greenfield rapid transit lines to Nubian and points south via a Shawmut Ave subway, and to Chelsea and/or Everett & east Malden via some moonshot project across the Mystic.

How to match existing frequencies:

• Reading - Back Bay - West Roxbury: 6 tph
• Oak Grove - Back Bay - Providence (making local stops in Boston): 4 tph
• cumulatively: Oak Grove - Forest Hills: 10 tph
• Waltham - Fairmount - Dedham/Norwood/Walpole/Foxboro: 4 tph
• South Station Upper - Fairmount - Franklin/Wrentham/Woonsocket/Milford: 4 tph
• cumulatively: Readville - Fairmount - South Station: 8 tph
• Framingham - Back Bay - North Shore: 4 tph
• North Station Upper - North Shore - Rockport/Newburyport: 4 tph
• cumulatively: North Shore - North Station: 8 tph

From what I understand, the NSRL will have a capacity of about 20 tph. The above services would leave 2 tph available for Amtrak and/or through-running longer-distance services (e.g. from Lowell).

Service to Providence with local stops in Boston is probably the most skeptical piece here. (Although I'll note that there would still be capacity for at least hourly semi-express service from Providence, because we're increasing the SW Corridor from 3 tracks to 5.) However, looking at the current schedules, the T claims that the Commuter Rail between Forest Hills and Back Bay is only 3 minutes faster than the Orange Line (!); with electrified service that can run at higher speeds in the suburbs, it might not actually be as infeasible as it sounds.

If the list above is giving you a headache, look at it like this:

• NSRL has 20 tph capacity
  • Allocate 10 to former Orange Line services
  • Allocate 2 to Amtrak/long distance
  • Allocate 8 for Indigo Line services, supplemented by surface-terminating short-turns
  • Extend former Orange Line services where possible to pick up Commuter Rail/Regional Rail routes to take advantage of the added track capacity

~~~

To be very clear to anyone reading this: this is not a serious proposal. I am not suggesting that the Orange Line be replaced by commuter rail. If anything, I'm suggesting the reverse: expand the Orange Line to replace parts of the commuter rail (and more aggressively/expansively than has generally been discussed before).

 

[Brattle Loop]

To be very clear to anyone reading this: this is not a serious proposal. I am not suggesting that the Orange Line be replaced by commuter rail. If anything, I'm suggesting the reverse: expand the Orange Line to replace parts of the commuter rail (and more aggressively/expansively than has generally been discussed before).

So, maybe I'm missing something (I'll concede not really parsing the TPH numbers), but it sounds like putting a ceiling on NSRL-enabled CR/RER frequency increases (in the form of forcing a disproportionate number of tunnel slots onto the former outlier Reading), or at the very least "mis-allocating" NSRL slots to lower-value services (at least, lower value in that they already have an existing transit route, and one with superior connections to the other RT lines given that OL-North would lose its cross-platform GL connection and get a probably-lower-quality RL connection, and OL-South would similarly lose its easy GL connection and get probably-lower-quality RL and BL connections), all to free up the Washington Street Tunnel for potential subway service expansion of questionable feasibility (Chelsea/Everett) and/or excessive difficulty (i.e. Nubian via OL versus the easier GL option) while pointedly avoiding any discussion of Congress Street's potential availability for future subway tunneling through the core if needed?

Yup, it's a Crazy Transit Pitch alright. Maybe it's me, but as a "solution" it's so ham-fisted and overcomplicated that it almost strikes me as exactly the kind of logic Baker & Company would come up with. Riverside, have you been moonlighting as MassDOT's sandbagging consultant without telling us? /s

All humor aside, it's actually a fairly-reasonable proposal for if there was some reason that it actually made sense to take the Orange Line out of the Washington Street Tunnel. Doing that's the crazy part, though on the other hand, given that we've seen the vulnerabilities of the tunnels lately, it does actually make sense to have an idea of how the NSRL could be temporarily pressed into service as an Orange Line replacement (though limited by the inability to cannibalize the existing OL tracks) by focusing additional service (even if at the temporary expense of other branches if necessary).

 

[Riverside]

Yup, it's a Crazy Transit Pitch alright. Maybe it's me, but as a "solution" it's so ham-fisted and overcomplicated that it almost strikes me as exactly the kind of logic Baker & Company would come up with. Riverside, have you been moonlighting as MassDOT's sandbagging consultant without telling us? /s

Hahaha, you caught me! This has been all a ruse to finish the 40-year project of killing the old Orange Line, one segment at a time!

(To be clear for anyone reading who -- like me -- sometimes misses sarcasm, I am completely joking about working for Baker and about wanting to kill the old Orange Line.)

...all to free up the Washington Street Tunnel for potential subway service expansion of questionable feasibility (Chelsea/Everett) and/or excessive difficulty (i.e. Nubian via OL versus the easier GL option)... All humor aside, it's actually a fairly-reasonable proposal for if there was some reason that it actually made sense to take the Orange Line out of the Washington Street Tunnel.

Yes, this is the crux of it. This is a Crazy Transit "Pitch" of questionable merit in order to enable a Crazier Transit Pitch of strong merit but questionable feasibility and cost. Because I will say: there should be a full rapid transit spine going down to Nubian, and likewise there should be a radial full rapid transit spine going to Chelsea & Everett. The El was a mistake and needed to come down, but the gap between the SW Corridor and the Fairmount Line is too wide (especially in the northern half of Dorchester). There should be spines on the Fairmount Line, on Washington/Shawmut, on Huntington, and on Boylston. Green Line to Nubian is by far the best option when balancing benefit, feasibility, and cost, but I would argue that we should still remember that it is a compromise, not an ideal.

I was actually prompted to think about this by a fantasy map that was shared on Twitter the other day:

https://twitter.com/i/web/status/1560725518202589186

Which is mostly reasonable, except for branching the Orange Line at Tufts and Sullivan. But there's a reason this person thought that was a good idea.

Furthermore, because of the way this map promotes the regional rail lines, it highlights how much the "new" (current) Orange Line parallels the mainline routes. In some alternate history out there, the SW Corridor, Fairmount, and Reading Lines were all Indigo-ified. If the New Haven railroad had electrified the SW Corridor in its early days and tried to replicate the success of the Boston, Revere Beach & Lynn, that could have been what happened all along.

Because it parallels the mainline railroads, the Orange Line's corridors are in some ways the most suited to being served Urban Rail-style by high-frequency (<6 min headways) layered branching services. Since we're gonna be doing that already (in this hypothetical future) to provide rapid transit service along Fairmount and potentially other corridors, why not consolidate like-with-like to maxmize flexibility and efficiency? And at the same time, remake the Orange Line (and its use of the Washington Street Tunnel) into something more like the Red Line or Blue Line.

So, maybe I'm missing something (I'll concede not really parsing the TPH numbers), but it sounds like putting a ceiling on NSRL-enabled CR/RER frequency increases (in the form of forcing a disproportionate number of tunnel slots onto the former outlier Reading), or at the very least "mis-allocating" NSRL slots to lower-value services

You're not missing something, that's basically what this is. But... two wrinkles for us to consider (in this hyper-hypothetical scenario):

First, it's possible we could get away with reducing slots to Reading depending on where the "new" Orange Line goes to the north. Malden is the major bus hub at that end of the line, but a route via Everett & Chelsea could still reach Malden and provide the RT frequencies needed there. Sullivan is the other hub, but you provide sufficient frequencies there by combining Reading and North Shore services. Vague examples below:

Second: it is true that this idea would cap capacity on the NSRL. But... one thing that stood out to me doing this was that... well, the cap is a problem but it's not actually that big of a problem. This comes back to something I wrote about a few months ago: the number of routes that should run through the NSRL is modest, not large. I admit this calculus changes if partial electrification becomes viable (eg batteries, dual-modes, etc), but I think it doesn't actually changes radically.

Assuming Orange eats Reading & West Roxbury, the North and South Sides both have ~3 within-128ish corridors that merit rapid transit-like service (what I called "Metro service"):

• North
  • Waltham
  • Woburn/Lowell
  • North Shore
• South
  • Newton/Framingham
  • Fairmount/Dedham
  • Brockton/Old Colony
  • Providence (ish)

It's "~3" because the divisions aren't perfectly clean... the B&A probably will not see as high frequencies as Fairmount because (imo) there need to be some expresses to service Worcester... Providence is distant but also Canton-and-inward will be doubled up by SCR... and Brockton could use through-run Metro service but will need to compete with other OCR routes, etc etc etc

But the exact numbers don't really matter. If we take the 20 tph capacity, reserve 2 slots for Amtrak (or whatever), then you have 18 tph. Divide that by ~3, and you get 6 tph on each of the corridors above, which is a through-run train every 10 minutes. And then on top of that, you'll continue to have services that run into the surface terminals, increasing frequencies on those corridors further.

And in fact, even if we bring Reading back into scope, then you have four corridors on each side: you could give each corridor 15-min through-running headways, double those up with surface-short-turns to provide 7.5-min headways on the inner segments (hello RT freqs), and still have 4 slots available for "Amtrak (or whatever)".

My point (at long last): yes, I've introduced a cap, but I don't think it's actually that far off from being manageable.

(at least, lower value in that they already have an existing transit route, and one with superior connections to the other RT lines given that OL-North would lose its cross-platform GL connection and get a probably-lower-quality RL connection, and OL-South would similarly lose its easy GL connection and get probably-lower-quality RL and BL connections)

Yes, these are key shortcomings, and they are probably the biggest flaws (and arguably fatal ones). The key question would be whether the "new" rerouted Orange Line would be able to mop up enough of the Orange Line's current riders to justify the impact.

while pointedly avoiding any discussion of Congress Street's potential availability for future subway tunneling through the core if needed?

Hey, I was already making two Crazy Transit Pitches, I didn't want to push it with a third

But yes -- in the event that the Orange Line needed to be rerouted out of Washington, Congress would probably be the stronger alternative compared to mainline conversion. That being said, the "like-with-like" element still holds some appeal to me. If I were going to build a new rapid transit subway in downtown, I'd want to devote it to sending service where I can't use mainline services. So, maybe like...

• Orange: Nubian to Everett via Washington
• Red: Ashmont/Mattapan & South Shore to Chelsea via Congress
• Indigo: West Roxbury & Fairmount to Reading & North Shore via NSRL

Anyway, I think for me the value in this exercise isn't necessarily about actually proposing resurrecting BERy's plans for the Orange Line and using the NSRL to clean up the rest -- rather it's about the insights picked up along the way: the Orange Line's corridors are a lot like the Indigo Lines', the relatively high available capacity on the NSRL upon closer inspection, the continued absence of rapid transit spines to dense neighborhoods (that old adage about "building transit where convenient rather than where needed" comes to mind) and so on.

 

[Tallguy]

So, here is a chart showing pre covid AM peak pass loads on OL

As you can see, southbound traffic greatly exceeds northbound, and I would suspect that development in the north will expand that disparity. This is why I support OL to Nubian.The move from 6 min frequency to 4.5 will mean that, even with OLX to the west, there will be excess capacity for a while to come. Adding more GL to the Central tunnel is asking for trouble.

 

[Brattle Loop]

As you can see, southbound traffic greatly exceeds northbound, and I would suspect that development in the north will expand that disparity. This is why I support OL to Nubian.The move from 6 min frequency to 4.5 will mean that, even with OLX to the west, there will be excess capacity for a while to come.

OL to Nubian...how? Replacing the Southwest Corridor alignment? (Is that what the chart's suggesting is possible, I don't know, it's pretty hard to read) Branching somewhere?

Adding more GL to the Central tunnel is asking for trouble.

Fortunately a Nubian branch would have to run out of the disused Tremont tunnels, meaning the only part of the Central Subway it has to touch is in the four-track section between Boylston and Park. It'd be less annoying if the outer Park loop was still there (reactivation candidate?) to eliminate weaving, but impacts on the subway could be minimized by turning the Nubian trains at Park. (Or, turning some other trains at Park. There's a decent bit of unused or under-used track capacity Park-Boylston.)

 

[Tallguy]

OL to Nubian...how? Replacing the Southwest Corridor alignment? (Is that what the chart's suggesting is possible, I don't know, it's pretty hard to read) Branching somewhere?



Fortunately a Nubian branch would have to run out of the disused Tremont tunnels, meaning the only part of the Central Subway it has to touch is in the four-track section between Boylston and Park. It'd be less annoying if the outer Park loop was still there (reactivation candidate?) to eliminate weaving, but impacts on the subway could be minimized by turning the Nubian trains at Park. (Or, turning some other trains at Park. There's a decent bit of unused or under-used track capacity Park-Boylston.)

Branching just southeast of Norton Park.

 

[Brattle Loop]

Branching just southeast of Norton Park.

I'd be curious to see how that'd shake out, given that while that chart appears to indicate that the southbound ridership is higher (north of DTX), each of the branches south of Tufts (presumably) would get their frequencies cut in half. 4.5 minute headways on the main trunk translates to what, 9 on the branches? Considerably less capacity than current-standard to the Southwest Corridor, so even if it could absorb that hit, it'd probably put a nasty ceiling on its growth capacity. And considering the amount of tunneling that would be needed, we're talking the kind of money where it'd make much, much more sense to spend (some of) it increasing capacity and removing bottlenecks that could hamper a Green Line branch to Nubian rather than sending an OL branch there. (That said, I'd definitely be curious to see where the breaking point in terms of capacity-in-TPH is before overcrowding on the OL Southwest Corridor starts tanking on-time performance, because that'd determine how much capacity there is to potentially sacrifice to other branches.)

 

[jklo]

Branching at Back Bay would be better.

 

[Tallguy]

Branching at Back Bay would be better.

But getting from BB to Nubian while also providing intermediate stops is problematic

 

[Tallguy]

I'd be curious to see how that'd shake out, given that while that chart appears to indicate that the southbound ridership is higher (north of DTX), each of the branches south of Tufts (presumably) would get their frequencies cut in half. 4.5 minute headways on the main trunk translates to what, 9 on the branches? Considerably less capacity than current-standard to the Southwest Corridor, so even if it could absorb that hit, it'd probably put a nasty ceiling on its growth capacity. And considering the amount of tunneling that would be needed, we're talking the kind of money where it'd make much, much more sense to spend (some of) it increasing capacity and removing bottlenecks that could hamper a Green Line branch to Nubian rather than sending an OL branch there. (That said, I'd definitely be curious to see where the breaking point in terms of capacity-in-TPH is before overcrowding on the OL Southwest Corridor starts tanking on-time performance, because that'd determine how much capacity there is to potentially sacrifice to other branches.)

So, the tunnels for GL or OL would be nearly identical, so I am unclear where there is savings to invest in other parts of GL.
And northern pass loads may require 3min frequency soon anyways, which would restore 6 min branches

 

[Brattle Loop]

So, the tunnels for GL or OL would be nearly identical, so I am unclear where there is savings to invest in other parts of GL.

Well, unless you're resurrecting the Elevated, the OL has to be tunneled all the way to Nubian. The Green Line...doesn't. (You could tunnel it, though I suspect the cost-benefit analysis wouldn't be favorable.) GL could technically surface at the old portal if eating the park was acceptable, otherwise the only mandatory tunneling is under the Pike/NEC.

And northern pass loads may require 3min frequency soon anyways, which would restore 6 min branches

Which may be sufficient, or it may not, so while I agree that the question isn't entirely answerable without further study, it can't just be handwaved away. 6 minutes is no (well, not much) better than what the the nominal (pre-01200-meltdown) standard was, and it's entirely unclear to me whether a semi-permanent 6 minute ceiling will be sufficient for the Forest Hills branch (especially in the potential scenario if it has to eat at least part of the Needham Line).

But getting from BB to Nubian while also providing intermediate stops is problematic

Yeah, by that point the line's pointing in completely the wrong direction. It'd be going from crazy transit pitch with emphasis on the transit pitch to crazy transit pitch with emphasis on the crazy. It's not ideal to have branching before BBY in a non-NSRL world because it cuts the frequency of OL trains running the NS-BBY transfer in half, but that isn't worth the significantly-harder lower-value route.

 

[Tallguy]

Well, unless you're resurrecting the Elevated, the OL has to be tunneled all the way to Nubian. The Green Line...doesn't. (You could tunnel it, though I suspect the cost-benefit analysis wouldn't be favorable.) GL could technically surface at the old portal if eating the park was acceptable, otherwise the only mandatory tunneling is under the Pike/NEC.



Which may be sufficient, or it may not, so while I agree that the question isn't entirely answerable without further study, it can't just be handwaved away. 6 minutes is no (well, not much) better than what the the nominal (pre-01200-meltdown) standard was, and it's entirely unclear to me whether a semi-permanent 6 minute ceiling will be sufficient for the Forest Hills branch (especially in the potential scenario if it has to eat at least part of the Needham Line).



Yeah, by that point the line's pointing in completely the wrong direction. It'd be going from crazy transit pitch with emphasis on the transit pitch to crazy transit pitch with emphasis on the crazy. It's not ideal to have branching before BBY in a non-NSRL world because it cuts the frequency of OL trains running the NS-BBY transfer in half, but that isn't worth the significantly-harder lower-value route.

Oh, joy, ANOTHER street running branch! Not enough chaos in the tunnel already? How is surface GL "equal or better" than the El?

 

[Tallguy]

Well, unless you're resurrecting the Elevated, the OL has to be tunneled all the way to Nubian. The Green Line...doesn't. (You could tunnel it, though I suspect the cost-benefit analysis wouldn't be favorable.) GL could technically surface at the old portal if eating the park was acceptable, otherwise the only mandatory tunneling is under the Pike/NEC.



Which may be sufficient, or it may not, so while I agree that the question isn't entirely answerable without further study, it can't just be handwaved away. 6 minutes is no (well, not much) better than what the the nominal (pre-01200-meltdown) standard was, and it's entirely unclear to me whether a semi-permanent 6 minute ceiling will be sufficient for the Forest Hills branch (especially in the potential scenario if it has to eat at least part of the Needham Line).



Yeah, by that point the line's pointing in completely the wrong direction. It'd be going from crazy transit pitch with emphasis on the transit pitch to crazy transit pitch with emphasis on the crazy. It's not ideal to have branching before BBY in a non-NSRL world because it cuts the frequency of OL trains running the NS-BBY transfer in half, but that isn't worth the significantly-harder lower-value route.

The data I posted, which shows a 33% possible ridership increase before bumping up against full loads. OLX to W.Rox ridership would mostly be mode shift from buses that already put people on the OL. And only half of Needham's ridership will ride OL, the other half would ride the GLX

 

[Brattle Loop]

Oh, joy, ANOTHER street running branch! Not enough chaos in the tunnel already? How is surface GL "equal or better" than the El?

Probably wouldn't be equal in terms of travel time (though how long did the Elevated take to go Dudley->Downtown?), though it would equal it in terms of restoring direct connections (inside fare control) to the other RT lines and the northern-half Commuter Rail. That said, "equal or better" was a bullshit lie spouted by the politicians to distract from the brutally idiotic thing they were doing in tearing down the Elevated. A Green Line surface branch would be inferior to the old Elevated and to an Orange Line subway branch, that's pretty much guaranteed. It would be a million miles better than the glorified silver-wrapped bus masquerading as a transit line that Nubian gets now. I get this is Crazy Transit Pitches, but that doesn't mean questions of feasibility can be jettisoned. A Green Line F-branch mainly on the surface would require a couple thousand feet of tunneling, less if you surface at and eat Elliot Norton Park, with no particular need for anything more complicated than a portal and incline (preferably in the Pike/NEC trench), plus rehabbing the old tunnels (and adding a station at Tufts under the park if desired). An OLX branch requires building a junction (and if the trunk's running 3 minute headways, is a flat junction going to cut it) presumably south of Tufts Medical Center, then digging somewhere between 1.5 and 2 miles more tunnel at the going rate (plus more for each additional station on the way to Nubian, as well as "Nubian Under" itself). Those things get weighed up, and the Green Line one's going to come out way, way, way cheaper than the OL version. Still going to be way cheaper even if you throw in some money for improvements elsewhere (say, reactivating the outer Park Street loop and cutting a crossover between Track 3 and Track 4 to help mitigate the GC backup and that tunnel bottleneck). Put head-to-head like that, the "better" option (OL) is going to get rejected in favor of the less-better one every time. This isn't the God Mode thread; translating "equal or better" into a functional transit pitch means being willing to concede that a lesser, feasible option might just be better than a more-perfect one that will never happen. (Though it might be worth doing some market research to determine whether Nubian and the surrounding areas are willing to accept a binary "Silver Line or Orange Line, those are the only choices" and the attendant risk of no change from the current lousy service solely to spite the people who tore down the EL. My personal feeling is that the answer's probably no.)

 

[Riverside]

So, setting aside for the moment the question of what it would be used for -- what's the status of the Canal Street Incline, particularly underground? As I understand it, the original portal location is the parking lot here: https://www.google.com/maps/place/4...29be52!4b1!8m2!3d42.364234!4d-71.059352?hl=en

(And it looks like that parking lot is accessed via an underpass through the building to the north.)

How much of the infrastructure remains in place underground? And how disprutive would the footprint of a new portal be? (e.g. impact on the buildings on that lot)

 

[F-Line to Dudley]

So, setting aside for the moment the question of what it would be used for -- what's the status of the Canal Street Incline, particularly underground? As I understand it, the original portal location is the parking lot here: https://www.google.com/maps/place/42°21'51.2"N+71°03'33.7"W/@42.3641987,-71.0594637,101m/data=!3m1!1e3!4m6!3m5!1s0x0:0x995a4d8f2729be52!4b1!8m2!3d42.364234!4d-71.059352?hl=en

(And it looks like that parking lot is accessed via an underpass through the building to the north.)

How much of the infrastructure remains in place underground? And how disprutive would the footprint of a new portal be? (e.g. impact on the buildings on that lot)

It's all there underground. They simply walled it off when the alignments switched and made an emergency exit out of it. The flat junction might be a little problematic if northern traffic levels increase beyond simply the two GLX branches, but it would be operationally compatible. The bigger challenge is simply what you'd do with it on the surface. Sure, you can snake a single track through the building service driveway onto Valenti Way and probably make it work if that single track segment were only a few feet long, but it's all hard-right and hard-left turns from there to get anywhere around the neighborhood. Maybe that's good enough for a boutique PCC-run historic tourist trolley on the Greenway and/or to the Navy Yard originating from Brattle Loop, but you're not going to get any truly useful or load-bearing transit out of the alignment with the time chew it takes to maneuver over to any thoroughfare. It would be absolute-bottommost priority compared to any/all other more useful things we could do with a reimagined Green Line.

 

[Brattle Loop]

So, setting aside for the moment the question of what it would be used for -- what's the status of the Canal Street Incline, particularly underground? As I understand it, the original portal location is the parking lot here: https://www.google.com/maps/place/42°21'51.2"N+71°03'33.7"W/@42.3641987,-71.0594637,101m/data=!3m1!1e3!4m6!3m5!1s0x0:0x995a4d8f2729be52!4b1!8m2!3d42.364234!4d-71.059352?hl=en

(And it looks like that parking lot is accessed via an underpass through the building to the north.)

How much of the infrastructure remains in place underground? And how disprutive would the footprint of a new portal be? (e.g. impact on the buildings on that lot)

The portal was actually a bit southeast of there, closer to about here (at least, where it opened into the outside). So while a good chunk of it is, as F-Line says, still down there, it's not entirely clear to me whether it would be possible to re-open it to LRV traffic.

I've never been entirely clear on where the current Green Line tunnel is through there. In the last few years of the Causeway Street Elevated, the Green Line got re-routed out of the old Orange Line end of the portal (the eastern end, which was actually the older end of the portal). They cut across the old Haymarket platforms to get the Green Line over there (hence those perennially-red signals in that tunnel), and built the North Station tunnel to the west of the temporary Green Line alignment (so, closer to the eastern end of the portal). I think some of the western portal alignment is now in use for the Green Line tunnel, and so isn't even theoretically available for re-use.

 

[Riverside]

Sure, you can snake a single track through the building service driveway onto Valenti Way and probably make it work if that single track segment were only a few feet long, but it's all hard-right and hard-left turns from there to get anywhere around the neighborhood. Maybe that's good enough for a boutique PCC-run historic tourist trolley on the Greenway and/or to the Navy Yard originating from Brattle Loop, but you're not going to get any truly useful or load-bearing transit out of the alignment with the time chew it takes to maneuver over to any thoroughfare. It would be absolute-bottommost priority compared to any/all other more useful things we could do with a reimagined Green Line.

Cool, yep, that's exactly what I was thinking -- I've been crayoning Greenway streetcars, and of the big question marks was around yard access. The more robust solution would be to hook into whatever portals get built near Pleasant Street, but that introduces a number of dependencies, so Canal Street makes for a useful option to have available "on Day 1".

And yeah: would not use it for revenue service, only for bringing cars in and out of service.

 

[Riverside]

The portal was actually a bit southeast of there, closer to about here (at least, where it opened into the outside). So while a good chunk of it is, as F-Line says, still down there, it's not entirely clear to me whether it would be possible to re-open it to LRV traffic.

I've never been entirely clear on where the current Green Line tunnel is through there. In the last few years of the Causeway Street Elevated, the Green Line got re-routed out of the old Orange Line end of the portal (the eastern end, which was actually the older end of the portal). They cut across the old Haymarket platforms to get the Green Line over there (hence those perennially-red signals in that tunnel), and built the North Station tunnel to the west of the temporary Green Line alignment (so, closer to the eastern end of the portal). I think some of the western portal alignment is now in use for the Green Line tunnel, and so isn't even theoretically available for re-use.

Hmm, well that is a little less conclusive. I'm not sure if it helps, but Open Street Map seems to have some detail here:

OpenStreetMap

OpenStreetMap is a map of the world, created by people like you and free to use under an open license.

www.openstreetmap.org

@vanshnookenraggen's track map suggests that the current tracks just follow the footprint of the old "outer tracks", running tangent, but I don't know how detailed he was able to be when researching that stretch. @The EGE, did you figure any of this out in the course of your Underground Station Layouts project?