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Second Avenue Subway Discussion


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On 4/5/2019 at 2:51 PM, Harlem Crosstown said:

I pressed enter by accident:

If we are to create any new subway track, it should mainly be connections to other places besides SAS obviously for the short term.

The larger question then becomes how we tie the Second Ave Subway into the system. It still runs through a huge chunk of Manhattan and needs feeder services to avoid becoming an orphan, so if we avoid tying into there now we're going to have to do it later.

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On 4/6/2019 at 3:05 PM, engineerboy6561 said:

The larger question then becomes how we tie the Second Ave Subway into the system. It still runs through a huge chunk of Manhattan and needs feeder services to avoid becoming an orphan, so if we avoid tying into there now we're going to have to do it later.

Phases 1 + 2 are well-integrated, as they are effectively the extension of the Broadway express tracks. However the new (T) service would cause a reverse branching situation, and so lower SAS (72 St - Hanover Sq) needs to be reevaluated.

Given the latent capacity on the (J)(Z) south of Essex and the (F) south of LES - 2 Ave, a Chrystie St II Connection could provide an additional pair of tracks up Midtown East while solving the yard access issue that the (T) will have.

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3 minutes ago, Caelestor said:

Phases 1 + 2 are well-integrated, as they are effectively the extension of the Broadway express tracks. However the new (T) service would cause a reverse branching situation, and so lower SAS (72 St - Hanover Sq) needs to be reevaluated.

Given the latent capacity on the (J)(Z) south of Essex and the (F) south of LES - 2 Ave, a Chrystie St II Connection could provide an additional pair of tracks up Midtown East while solving the yard access issue that the (T) will have.

If you were to tie the (T) into the (F) at LES-2 Av then you have options; the bigger question is how you integrate things. The (G) runs 6-9 tph and the (F) runs 15tph or so, which would mean that the (T) would be limited to 6-9tph on the south end if you put it on Culver (unless you use the (F) as Culver Express and give the (T) merge priority at the Bergen St interlocking, which would let the (T) run at 15tph). The situation would be better if you ran the (T) down Nassau, as the (J)(Z) run approximately 8-10tph, and the (R) also runs 8-12tph. The space for a 15tph (T) is there along the tracks, but the issue with running down 4 Av is going to be terminal capacity; if I had to guess I'd peg the turning capacity at Bay Ridge around 10-12tph (which might not leave room to turn (T) trains), while running the (T) to Church as the Culver local would lead to a terminal that could comfortably turn 30tph.

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To start off, any 2nd Av service that does not run to Broadway should either terminate at 72nd on a new lower level, run under 2nd as an express line, or run to Queens before or after 72nd (new level). Express/local service south of 72nd would also be great but far more unlikely. Under a realistic plan the (N) would run to Fordham Plaza via 2nd and 3rd and . the (Q) would run via 2nd and 125th to 125th/St Nicholas while the (T) would terminate at 72nd on a new lower level. 

I personally think sending the (T) to southern Brooklyn to replace the (B) or (D) is a waste... most people are looking for central Manhattan services there. However, I would definitely consider Phase 4 a waste (excluding the Houston-Grand part). This leaves with three options:

1. Send the (T) to Metropolitan via a link to Chrystie after Houston. This preserves the Midtown-Williamsburg link whilst allowing the (M) to run to southern Brooklyn and receive 10 car trains; these two things allow for it to receive 10 car trains which can allow for QBL/Culver/Broadway to be reorganized ( (N) up 2nd, (R) to Astoria, (W) eliminated, (E) QBL local to 179th, (F) express on Hillside and Culver, (M) on Culver local and via 63rd and QBL express to Jamaica Center). The biggest issue with this proposal is the isolation of 2nd Avenue, but Williamsburg has many transfer options ( (L) , (G) if new stop at Union Avenue is built, (J)(Z) to connect to many other lines, and (F)).  In the end, the (T) would run Metropolitan-72nd. If you wanted you could also replace the (T) the  :M: and the (M) with the (V) .

2. Send the (T) to Jamaica Center. Under this plan you would have to install a third track between Crescent and Broadway Junction to allow the (J) to run local (and terminate at Crescent) while the (T) runs express between Marcy and Crescent. (Z) and skip stop service would be cut under this plan. While this plan would be great in giving Midtown service to (J) riders, it suffers from many of the fallbacks that the previous proposal does. You also would still have the problem of QBL interlining.

3. Send the (T) down Culver. Under this plan you could omit the 2nd Av transfer as you it would be unnecessary and require a sharp curve. Under this plan the (T) would run via Culver express down to Coney Island while the (F) would run via Culver local and terminate at Church (the (G) would be extended to 18th center). This would provide Culver and southern Brooklyn with an east side service and Culver express but would interline 2nd and 6th.  

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3 hours ago, Caelestor said:

Phases 1 + 2 are well-integrated, as they are effectively the extension of the Broadway express tracks. However the new (T) service would cause a reverse branching situation, and so lower SAS (72 St - Hanover Sq) needs to be reevaluated.

Given the latent capacity on the (J)(Z) south of Essex and the (F) south of LES - 2 Ave, a Chrystie St II Connection could provide an additional pair of tracks up Midtown East while solving the yard access issue that the (T) will have.

Fully agree that lower SAS needs to be re-evaluated. It will have significantly less service than upper SAS. But if the (T) runs via (J)(Z) south of the LES, lower SAS will still be limited to just the (T) below 72nd and above the (J) merge.

3 hours ago, engineerboy6561 said:

If you were to tie the (T) into the (F) at LES-2 Av then you have options; the bigger question is how you integrate things. The (G) runs 6-9 tph and the (F) runs 15tph or so, which would mean that the (T) would be limited to 6-9tph on the south end if you put it on Culver (unless you use the (F) as Culver Express and give the (T) merge priority at the Bergen St interlocking, which would let the (T) run at 15tph). The situation would be better if you ran the (T) down Nassau, as the (J)(Z) run approximately 8-10tph, and the (R) also runs 8-12tph. The space for a 15tph (T) is there along the tracks, but the issue with running down 4 Av is going to be terminal capacity; if I had to guess I'd peg the turning capacity at Bay Ridge around 10-12tph (which might not leave room to turn (T) trains), while running the (T) to Church as the Culver local would lead to a terminal that could comfortably turn 30tph.

But if I had to choose between running the (T) via the (J) and (R) to Bay Ridge or via the (F) to Coney Island, I would choose the first option. Even then, the best you can get under that scenario would be roughly 20 tph (I’m fully aware of the long-term plans to install CBTC systemwide and run more frequent trains per hour, but first, MTA needs to prove they’re actually capable of doing it).

Edited by T to Dyre Avenue
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I still say it would be better to send the (T) maybe after Seaport if not Hanover Square via a new Schermerhorn Street Tunnel and have it come into Brooklyn at Court Street (current Transit Museum, which could be moved if that were needed), then coming in on the currently-unused local tracks at Hoyt-Schermerhorn and then becoming the Fulton Street Local to Euclid while the (A) becomes full-time to the Rockaways, split between Far Rockaway and Rockaway Park on likely a 4-3 split (four to FR, three to RP) except late nights when it would be an even split, running every 15 minutes instead of 20 so both branches get half-hourly service and the (C) running to Lefferts at all times except late nights (when the (T) would be extended to Lefferts) since it would now be a full-time Fulton Express (or if you want to de-interline 8th Avenue, the (C) being all times between 168 and Chambers and the (E) running at all times between Jamaica Center and Lefferts, express at all times including late nights on both and the (A)).

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On 4/12/2019 at 3:41 AM, Wallyhorse said:

I still say it would be better to send the (T) maybe after Seaport if not Hanover Square via a new Schermerhorn Street Tunnel and have it come into Brooklyn at Court Street (current Transit Museum, which could be moved if that were needed), then coming in on the currently-unused local tracks at Hoyt-Schermerhorn and then becoming the Fulton Street Local to Euclid while the (A) becomes full-time to the Rockaways, split between Far Rockaway and Rockaway Park on likely a 4-3 split (four to FR, three to RP) except late nights when it would be an even split, running every 15 minutes instead of 20 so both branches get half-hourly service and the (C) running to Lefferts at all times except late nights (when the (T) would be extended to Lefferts) since it would now be a full-time Fulton Express (or if you want to de-interline 8th Avenue, the (C) being all times between 168 and Chambers and the (E) running at all times between Jamaica Center and Lefferts, express at all times including late nights on both and the (A)).

I recommend using the (W) instead. Better track pairing and SAS in Brooklyn should mainly focus on connections.

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Here’s how I would run service:

(T)(V) from Queens on a connection to QBL local after Forest Hills. 

(T) would run to Culver Express and Coney Island with (F) terminating at 18th and (G) at Church.

(V) would run on the Jamaica Line to a Jamaica Express, ending at Jamaica Center. Yes I am aware the (V) would have very close terminals, so I think the (V) at north end could run on a Northern Blvd subway.

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Any reorganization of Fulton should have the (R) run out to Euclid via a new tunnel between Hoyt and Whitehall via State Street; SAS capacity is better for Brooklyn and the IND won't help in connections or time as it would require SAS phase 4.  The best option IMO is this: (note all Eastern division lines would get 10 car platforms; you would also connect the 6th express tracks to Nassau Chrystie and add a third track between Cypress at Broadway Junction)

(A) splits RPK/Far Rockaway

(C) rerouted to Fulton; express in Brooklyn and Manhattan south of 50th (you'd install a higher-speed switch to improve merging given how slow the Canal switch is)

(E) 179th-WTC via QBL local, 53rd and 8th local

(B) Metropolitan- BPB weekdays, 145th weekends, Essex late nights

(D) Jamaica Center-205th via Jamaica express between Crescent and Essex (trains would now skip Marcy by re-connecting the center track)

(F) express on Hillside/Culver

(M) Jamaica Center-Church Av via QBL express, 63rd, 6th local and Culver local

(G) extended to 18th

(N) Fordham Plaza- CI  via 3rd in Bronx/ 2nd in Manhattan; skips 49th

(Q) 125th/St. Nicholas- CI

(R) Astoria- Euclid

(W) eliminated

(J) Crescent-Bay Ridge via Broadway-Brooklyn local, Nassau and 4th local

(Z) eliminated 

(T) new lower level at 72nd- CI via 2nd, 4th express and West End

turquoise (V) 72nd lower- Ocean Parkway via 2nd and Brighton express (trains would run to Ocean Parkway as provided that closer switches are installed you could turn more tph than at Brighton due to the absence of a curve)

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13 minutes ago, R68OnBroadway said:

(J) Crescent-Bay Ridge via Broadway-Brooklyn local, Nassau and 4th local

This is the one question I have about your plan. How do you plan to mitigate the capacity impact on the (B)(D) that running such a service via shared tracks on the WillyB would have? Don't you think it's better to simply run it to Essex?

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47 minutes ago, RR503 said:

This is the one question I have about your plan. How do you plan to mitigate the capacity impact on the (B)(D) that running such a service via shared tracks on the WillyB would have? Don't you think it's better to simply run it to Essex?

You could cut it back to Essex (provided there are four tracks); the only reason why I kept the (J) on Jamaica was to eliminate the need for split (D) service.

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On 2/19/2019 at 3:10 AM, engineerboy6561 said:

The pillars on the Dubai metro (what that photo up there is from are about 6-7 feet wide, which is a bit wide to do on some of the older NYC streets where we have elevated lines, especially if we're looking at running three- or four-track lines with 600' trains on each track as opposed to two-track lines running 300' trains (Dubai), and the spacing looks about 100' apart on average. Doing some back-of-the envelope analysis, a single R160 car weighs about 86,000 lbs over a length of 60 feet, so we have a base unit for how much weight a column has to sustain. If we want to assume that we can place columns every 50 feet (as per the standard distance quoted in this reference), and that we can basically assume a viaduct structure that successfully forces all the load onto the columns (which I have to do because I'm an EE and not a structural engineer) the maximum load on a four-track structure between columns would be 43,000lbs*8 (assuming that we can treat the bogies as point loads, and that car weight is split equally between bogies, each car comprises two 43,000lb point loads) because that's equal to a pair of coupled cars passing over each of four tracks at once, and we have a maximum load per segment of 344,000 lbs. According to this engineering calculator here, a cylindrical reinforced concrete column of 30" diameter with eight steel rebars in it is good for about 1.899 million pounds. 

Assuming you can build a sufficiently rigid structure to transmit the load down to the columns you could probably use a viaduct structure that looks something like this:

zPiQScR.png

The specific structure I roughed out here has about 16,320 cubic feet of concrete per bridge segment, and assuming a 145lb/cubic foot concrete density gives us about 2.37 million pounds. If we assume that each support is resting half on one pair of columns and half on the other, we have an average static load of 2.37 million pounds per column pair, which comes down to about 1.185 million pounds per column. If we add the maximum total load of 344,000 lbs to this number, we have a total per-column load of 1.357 million pounds, which gives me about a 29% margin of safety on the columns; I'd love for an actual engineer to chime in and critique this design, but something like this could be relatively easily placed on most city streets that currently carry elevated trains, and could be fairly easily designed for noise and vibration rejection to reduce the noise load on local residents.

Then why don't the MTA Replace the Noisy Metal El with this then?

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55 minutes ago, subwayfan1998 said:

Then why don't the MTA Replace the Noisy Metal El with this then?

They could, but the process for each line can take years and this can pose as a disservice to certain communities who only have access to the elevated line that would be theoretically be replaced. Think of the (7) or the (J)(Z) for example. While it’d be nice to upgrade the EL structures along each route, we can’t because of the huge inconvenience that it’ll cause riders in the short term. 

Also, not to confuse you, I’m all for short term inconveniences under the promise that we receive long term benefits. However, the (MTA) can use this modern style of EL’s to build new lines or extensions such as the (N)(W) to LaGuardia. 

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If we want anything more finished within our lifetimes, I propose creating a Phase 1.5. The space leading up to 106th Street and from 110th to 120th has already been excavated decades ago. If you clear out four blocks of dirt, the line will reach up to 120th Street continuously, plenty of space for tail tracks. Why not get the 106th Street and 116th Street stations open before digging that expensive curve to 125th? Let's get East Harlem some better service sooner than later, yeah?

Edited by Porter
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2 hours ago, Porter said:

If we want anything more finished within our lifetimes, I propose creating a Phase 1.5. The space leading up to 106th Street and from 110th to 120th has already been excavated decades ago. If you clear out four blocks of dirt, the line will reach up to 120th Street continuously, plenty of space for tail tracks. Why not get the 106th Street and 116th Street stations open before digging that expensive curve to 125th? Let's get East Harlem some better service sooner than later, yeah?

You would have to remove columns and rebuild part of the structure for crossovers to turn trains. You would also need crew facilities, among other additional expenses.

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On 4/15/2019 at 6:09 PM, Harlem Crosstown said:

Here’s how I would run service:

(T)(V) from Queens on a connection to QBL local after Forest Hills. 

(T) would run to Culver Express and Coney Island with (F) terminating at 18th and (G) at Church.

(V) would run on the Jamaica Line to a Jamaica Express, ending at Jamaica Center. Yes I am aware the (V) would have very close terminals, so I think the (V) at north end could run on a Northern Blvd subway.

(T) should run from Broadway - 125th Street to Cambria Heights - 234th Street

(V) from 2nd Avenue to Rockaway Park - Beach 116th Street via Rockaway Queensway

On 4/15/2019 at 6:38 PM, R68OnBroadway said:

Any reorganization of Fulton should have the (R) run out to Euclid via a new tunnel between Hoyt and Whitehall via State Street; SAS capacity is better for Brooklyn and the IND won't help in connections or time as it would require SAS phase 4.  The best option IMO is this: (note all Eastern division lines would get 10 car platforms; you would also connect the 6th express tracks to Nassau Chrystie and add a third track between Cypress at Broadway Junction)

(A) splits RPK/Far Rockaway

(C) rerouted to Fulton; express in Brooklyn and Manhattan south of 50th (you'd install a higher-speed switch to improve merging given how slow the Canal switch is)

(E) 179th-WTC via QBL local, 53rd and 8th local

(B) Metropolitan- BPB weekdays, 145th weekends, Essex late nights

(D) Jamaica Center-205th via Jamaica express between Crescent and Essex (trains would now skip Marcy by re-connecting the center track)

(F) express on Hillside/Culver

(M) Jamaica Center-Church Av via QBL express, 63rd, 6th local and Culver local

(G) extended to 18th

(N) Fordham Plaza- CI  via 3rd in Bronx/ 2nd in Manhattan; skips 49th

(Q) 125th/St. Nicholas- CI

(R) Astoria- Euclid

(W) eliminated

(J) Crescent-Bay Ridge via Broadway-Brooklyn local, Nassau and 4th local

(Z) eliminated 

(T) new lower level at 72nd- CI via 2nd, 4th express and West End

turquoise (V) 72nd lower- Ocean Parkway via 2nd and Brighton express (trains would run to Ocean Parkway as provided that closer switches are installed you could turn more tph than at Brighton due to the absence of a curve)

My Idea is:

(N) Coney Island - Stillwell Avenue to Little Neck - Little Neck Parkway

(Q) Coney Island - Stillwell Avenue to Co-Op City

(R) Bay Ridge to Floral Park - Langdale Street.

(W) Chelsea, Travis Avenue in Staten Island to 30th Avenue - College Point.

(A) Inwood-207th Street to Far Rockaway - Mott Avenue

(C) 168th Street to Cambria Heights - 234th Street

(E) Lefferts Boulevard to Queens Village - Springfield Boulevard

(B) Brighton Beach to Co-Op City

(D) Coney Island - Stillwell Avenue to Co-Op City

(F) Coney Island - Stillwell Avenue to Floral Park - Little Neck Parkway

(M) Woodside - Roosevelt Avenue to Floral Park - Langdale Street via QBL, Manhattan Bridge and 6th Avenue (Loop Line)

(G) 18th Street to Rockaway Park - Beach 116th Street via Rockaway Queensway

(L) 72nd Street - Upper West Side to Canarsie - Rockaway Parkway.

(J) Rosedale - Hook Creek Boulevard to Prospect Park

(Z) Rosedale - Hook Creek Boulevard to Chambers Street

These Extensions would help They would help to serve public transit “deserts” like eastern Queens, a few section of Brooklyn especially in southeast corner, North Riverdale and Co-op City in the Bronx, and Staten Island.

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16 minutes ago, Union Tpke said:

You would have to remove columns and rebuild part of the structure for crossovers to turn trains. You would also need crew facilities, among other additional expenses.

Absolutely, that should all be done too. It still delays the expense of 125th Street, since you're just pushing the current terminus north, along with all the modifications that such a transposition requires.

Edited by Porter
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