Second Avenue Subway Discussion

[bobtehpanda]

It would've been an intriguing architectural decision to leave the cavern walls as bare rock (with waterproofing, of course), as is done in Stockholm.

 

 

Bit too late for that, though.

[Tokkemon]

Yeah I really wonder what that would look like. I've always admired Stockholm's subway for its bare-rock architecture. But New York loves its glass and steel!

[CenSin]

Suppose additional tracks were added to this line, how feasible do you think this would be? The physical structures don't appear to lend much room for improvement. Bored tunnels are literally set in stone.

[Tokkemon]

Perhaps build a second tunnel directly below?

[Eric B]

Yeah I really wonder what that would look like. I've always admired Stockholm's subway for its bare-rock architecture. But New York loves its glass and steel!

I saw bare rock the one time I peeked into a MARTA station!

[Wallyhorse]

Perhaps build a second tunnel directly below?

That is something I would do at 72nd Street for an SAS line that would run to Queens via 79th Street (with a stop on such a line at York-1st Avenues before going to/after coming from Queens that I would do as a three-track station that can also serve as a short-turn SAS terminal).  Such trains on the lower level would join either the or after 72nd going south as the heads to Broadway or the heads to lower Manhattan.  This could perhaps be the LaGuaradia line if it stayed underground until reaching the airport.

[CenSin]

Perhaps build a second tunnel directly below?

The issue would be connecting the tunnels for switches. While a cut-and-cover structure could be modified to merge and/or join tunnels (such as what's been done with the 63 Street connector), bored tunnels don't have the flexibility.

[bobtehpanda]

The issue would be connecting the tunnels for switches. While a cut-and-cover structure could be modified to merge and/or join tunnels (such as what's been done with the 63 Street connector), bored tunnels don't have the flexibility.

 

You don't necessarily have to connect the express tracks to the local tracks.

 

In any case, the SAS will be able to run 30 TPH under today's signalling, or up to 40 TPH with the CBTC technology being installed across the system. This should be more than enough for the forseeable future, even if links to the Bronx and Queens are used to capacity (which is doubtful since the MTA doesn't have plans to build either an extension west of Park, an extension north under the Harlem River, or a Queens bypass anytime soon). Having express tracks not connecting to anything would be kind of a waste...

Edited November 13, 2013 by bobtehpanda

[exseed]

If they were to add express service on the SAS, they wouldn't necessarily need seperate express tracks. It is possible to run express services on a two-track line. There just needs to be a couple or so local stations build with bypass tracks so as to allow express trains to pass stopped local trains. Assuming the  would get CBTC, the timing and coordinating of expresses passing locals shouldn't really be an issue.

Edited November 16, 2013 by exseed

[bobtehpanda]

If they were to add express service on the SAS, they wouldn't necessarily need seperate express tracks. It is possible to run express services on a two-track line. There just needs to be a couple or so local stations build with bypass tracks so as to allow express trains to pass stopped local trains. Assuming the  would get CBTC, the timing and coordinating of expresses passing locals shouldn't really be an issue.

 

...which would be true in most countries, since most countries do not interline trunk routes.

 

However, throwing that into the mix on the specifically is going to be an absolute disaster. It would have knockback effects on Broadway, Second Avenue, and (presumably) the 63rd St tunnel, creating a whole lot of messes. Not to mention, it's not about having express for the sake of having express - the long interstation distances already achieve a semi-express configuration. It's about increasing capacity, which the complexities of a limited express system would hinder.

[Brighton Express]

If they were to add express service on the SAS, they wouldn't necessarily need seperate express tracks. It is possible to run express services on a two-track line. There just needs to be a couple or so local stations build with bypass tracks so as to allow express trains to pass stopped local trains. Assuming the  would get CBTC, the timing and coordinating of expresses passing locals shouldn't really be an issue.

 

is gonna have to get some CBTC sometime soon anyways that thing is crowded 24/7. I don't really see a two track express working. To me it just seems like a 4 track would work better. At minimum, I think there should atleast be a third track added to the SAS.

[RollOver]

SAS is better off being 2-tracks to alleviate severely overcrowding on the local. I don't see how express service on SAS would work. You have the doing all that work.

[Mtatransit]

There could always be a M15 Super Express but I dont agree with it, but hey once the second Av subway opened M15 will get reduced anyways

[Roadcruiser1]

Face it. The trunk lines that we have now with express service was built in the day when building it was cheap. Labor was cheap, steel was cheap, and etc. Nowadays it's done by unionized workers that get paid $40,000+ a year, laying track costs $700+ a ton, steel is $400+ a ton, and concrete is $150+ per cubic yard. Let's not forget to mention that you have to pay for architects, engineers, machinery, studies, urban planners, and etc. You guys get the message. Express tracks are not going to probably happen today. It's too expensive. Most of our new subway lines will probably have only two tracks. Though I do see future modifications on current trunk lines to help with our problems today.......

[RollOver]

I still don't see the point of express service on SAS. It's not like its needed anyway. I can sort of understand for extra capacity and just in case anything disrupts local service but other than that, I see no point of it at all. The express will only end up with virtually nobody on it. It's important to keep virtually every trains/buses crowded, in part to save enough money.

[Brighton Express]

SAS is better off being 2-tracks to alleviate severely overcrowding on the local. I don't see how express service on SAS would work. You have the doing all that work.

 

I don't see what the problem with Express on the SAS would be. You might want to revise that because all the work the are doing makes them both severely overcrowded, which is what we are trying to fix with the SAS. The even though it is not as crowded as the , still has its share. Express would work great to clear up a bit of the overcrowding on all three lines. Even a 3 track peak direction would get the job done.

[bobtehpanda]

I don't see what the problem with Express on the SAS would be. You might want to revise that because all the work the are doing makes them both severely overcrowded, which is what we are trying to fix with the SAS. The even though it is not as crowded as the , still has its share. Express would work great to clear up a bit of the overcrowding on all three lines. Even a 3 track peak direction would get the job done.

 

1. There is never going to be a three-track peak direction. The plans specifically call for 2 tracks, and it has been this way since 1968. If, implausibly, at some later date the MTA decides it has the money to build express, it's not going to go to the trouble of digging up a whole new launch box and make new stations just for a third track bore. Heck, the MTA doesn't even have a timeline for SAS completion, and this doesn't include long-sought-after connections to new lines in the Bronx, Brooklyn, or Queens.

 

2. The SAS already has ridiculously long interstation distances, so you wouldn't be able to skip very much (and 2nd Av is no CPW) The current extension is going to be three stops. The next extension after that? Another three stops. Using IRT express stop spacing, that would mean one express stop in between, and this would be of dubious benefit to anyone since the train doesn't go any farther than 125th.

 

3. Where would the trains from a third or fourth pair of track go? Capacity can only be fully used if the trains have somewhere to go, and the last I checked, only two tracks connect from Broadway and 63rd to Second Avenue. The two tracks on the SAS stubway won't even be utilized to full capacity; IND signalling allows for 30 TPH (as on the QBL), but there is no way in hell that 30 TPH is being shoved down the Broadway express.

 

Building express tracks on the SAS right now would be sort of like the express tracks on the Astoria Line: they don't really get you quicker anywhere, they don't boost capacity due to a two-track bottleneck, and they skip heavily used stations with rising ridership. It wouldn't help anybody.

[RollOver]

Besides, many of the Upper East Side residents work in the CBDs everyday for work anyway. For example, the ride from 125th to 59th is not long enough to warrant express service on SAS. They will take whichever train comes first, therefore, proving a misallocation of resources. What matters is saving money, not about satus quo. That's all. This is not the , where many of its riders in the Bronx head for the CBDs for work rather than Central Park West.

Edited November 23, 2013 by RollOverMyHead

[realizm]

2. The SAS already has ridiculously long interstation distances, so you wouldn't be able to skip very much (and 2nd Av is no CPW) The current extension is going to be three stops. The next extension after that? Another three stops. Using IRT express stop spacing, that would mean one express stop in between, and this would be of dubious benefit to anyone since the train doesn't go any farther than 125th.

 

With Phase 2 remember that right before the swing into 125th Street engineers already planned to construct an overengineered spur that will become the junction for a future Bronx extension as it is built. But until that happens correct as you put it 'dubious benefit' if the line will not go farther then 125th Street until whenever the MTA can start with the Bronx extension in the deades to come.

 

[bobtehpanda]

With Phase 2 remember that right before the swing into 125th Street engineers already planned to construct an overengineered spur that will become the junction for a future Bronx extension as it is built. But until that happens correct as you put it 'dubious benefit' if the line will not go farther then 125th Street until whenever the MTA can start with the Bronx extension in the deades to come.

 

 

The issue becomes then, which stations do you skip? Midtown already has wide stop spacing, so you'd probably end up with an Eighth Av situation where only one or two stops gets skipped (Eighth Av expresses south of PABT only skip 23rd and Spring)

 

Stops you could justify skipping; Seaport(?), Chatham Sq (?), 23rd, 86th(?), 106th. The rest would either be transfer points to congested lines (Grand, Houston, 14th, 34th, 42nd) or merge points where one could transfer to other services using the line (72nd, 116th) or both (50th). Unless Grand is significantly expanded, Chatham should remain express to reduce loading at the one mezzanine at Grand (which is already crowded to ridiculous levels during the peak), and 86th is the end of a 14-block gap in service. Seaport would also be a heavily used stop due to all the offices over there (and even more so should "Seaport City" get built).

 

That basically leaves 23rd and 106th.

[Wallyhorse]

That's true, this is a case there are no really good spots for an "express" to skip stops the way this is set up except for MAYBE 23rd street.  Only if it's REALLY necessary to go to four tracks should that even be considered.

Frankly, I would much rather spend such money on a Queens branch of the SAS that would run through a new tunnel through 79th Street with a stop at 79th Street/York-1st Avenues that can serve as a three-track station for short turns.  This could in turn be a potential branch either to LaGuardia or perhaps if the Rockaway branch is re-activated as a more direct Manhattan branch.  If not that, it would be to extend Phase 2 all the way across 125th Street to an elevated terminal at Broadway-12th Avenue/Riverside Drive (and a transfer to the ) since by the time such were done, Columbia should be finished with their expansion and an extended Phase 2 can serve Columbia.

[Tokkemon]

Why must you mention 1st Ave every post you make?

[bobtehpanda]

That's true, this is a case there are no really good spots for an "express" to skip stops the way this is set up except for MAYBE 23rd street.  Only if it's REALLY necessary to go to four tracks should that even be considered.

 

Frankly, I would much rather spend such money on a Queens branch of the SAS that would run through a new tunnel through 79th Street with a stop at 79th Street/York-1st Avenues that can serve as a three-track station for short turns.  This could in turn be a potential branch either to LaGuardia or perhaps if the Rockaway branch is re-activated as a more direct Manhattan branch.  If not that, it would be to extend Phase 2 all the way across 125th Street to an elevated terminal at Broadway-12th Avenue/Riverside Drive (and a transfer to the ) since by the time such were done, Columbia should be finished with their expansion and an extended Phase 2 can serve Columbia.

 

1. There are many good ways to extend to Queens. This is not one of them.

 

2. What would be the point of elevating a subway line that is already well below the surface? How would such a line come to the surface in the first place (and please don't say eminent domain, because it's not happening).

 

The costs of going elevated for such a short stretch are not worth the money.

[realizm]

That's true, this is a case there are no really good spots for an "express" to skip stops the way this is set up except for MAYBE 23rd street.  Only if it's REALLY necessary to go to four tracks should that even be considered.

 

Frankly, I would much rather spend such money on a Queens branch of the SAS that would run through a new tunnel through 79th Street with a stop at 79th Street/York-1st Avenues that can serve as a three-track station for short turns.  This could in turn be a potential branch either to LaGuardia or perhaps if the Rockaway branch is re-activated as a more direct Manhattan branch.  If not that, it would be to extend Phase 2 all the way across 125th Street to an elevated terminal at Broadway-12th Avenue/Riverside Drive (and a transfer to the ) since by the time such were done, Columbia should be finished with their expansion and an extended Phase 2 can serve Columbia.

 

We already have a tunnel to do the job to give 2nd Ave riders Queens access --- 63rd Street. The MTA already thought this out.

 

The 63rd Street tunnel has a pair of spurs that already exists which brings phase three 's to the Queens Blvd Line. Right east of 63rd Lex. (not west with the BMT trackage that switch is for uptown into phase 1 and 2.) 

 

You can railfan it for yourself it's there.

Edited December 1, 2013 by realizm

[Wallyhorse]

2. What would be the point of elevating a subway line that is already well below the surface? How would such a line come to the surface in the first place (and please don't say eminent domain, because it's not happening).

 

The costs of going elevated for such a short stretch are not worth the money.

The reason on an extended Phase 2 I would go elevated at the end for the SAS is for the same reason the is elevated at that point: It's in a valley.

 

The 1 is actually on the same level at 125th as it is elsewhere, it's the street itself that comes down as far as it does.

 

That's why I would go elevated there.