UPDATE (09.18.2021): Several images updated. In an earlier update, I revised this post for clarity.
In my last post, I discussed the South Brooklyn de-interlining. So far, the de-interlining plans contemplated by NYTIP only involve operational changes. In this post, we’ll explore the Broadway (N, Q, R, and W) and Queens Boulevard (E, F, M, and R) trunk lines. While de-interlining the former is trivial, the latter is much more challenging.
Note: Click any image to enlarge.
The Broadway trunk line runs from 57th Street and 7th Avenue to Canal Street in Manhattan. The N and Q trains run express and cross the Manhattan Bridge, while the R and W trains run local via Lower Manhattan. Conflicts occur north of 34th Street – Herald Square station when the N joins the R and W on the local tracks; the three services run together until reaching Queens, where the N and W serve Astoria and the R serves Queens Boulevard. Meanwhile, the Q serves the Second Avenue Subway (SAS) via 63rd Street.
[Fig. 1] Snippet of vanshnookenraggen’s track map showing Broadway line conflicts.
This pattern causes delays and restricts N, R, and W service since they share tracks from the 60th Street tunnel to Times Square. To address these issues under NYTIP:
Reroute N trains via the Second Avenue Subway (SAS).
[Fig. 2] Overview of the N reroute, via Brand New Subway.
With this reroute, the N no longer switches to the local tracks north of 34th Street; instead, it runs with the Q to 96th Street and 2nd Avenue. With only the R and W on 60th Street, there is now room to increase service on both lines to make up for the loss of the N.
While it appears Astoria will lose substantial service, this is actually not the case. At present, combined N/W service in Astoria runs approximately every 4 minutes during peak hours. With the 60th Street bottleneck eliminated, one service alone could provide such frequency. To maximize improvements, NYTIP prescribes changes to Queens Boulevard service in conjunction with the N train reroute that will improve service on both the Queens Boulevard and Astoria lines.
II. Queens Boulevard
[Fig. 3] Snippet of the NYC Subway map showing the Queens Boulevard trunk line and branches.
The Queens Boulevard (QB) trunk line serves three distinct Manhattan trunk lines and connects to many other lines, making it one of the busiest corridors outside of Manhattan. It serves 8th Avenue (E train), 6th Avenue (F and M trains), and Broadway (R train). E and F trains run express in Queens, with E trains entering Manhattan via 53rd Street and F trains entering Manhattan via 63rd Street. M and R trains run local, with M trains entering Manhattan via 53rd Street and R trains entering Manhattan via 60th Street. This pattern poses several conflicts:
- The E express and M local merge near Queens Plaza.
- The F express diverges west of 36th Street station to serve the 63rd Street line; this switch induces delays on the QB express.
- Forest Hills – 71st Avenue, due to its nature as a relay terminal for the M and R trains, induces delays on the QB local.
[Fig. 4] Illustration of existing conflicts on the QB and Astoria lines.
Unfortunately, addressing these conflicts is not trivial. In 2018, vanshnookenraggen explored some of these difficulties at length; he proposed sending the R to Astoria and rerouting the N via 63rd Street to Forest Hills to replace the R. Honestly, I don’t think it’s a bad plan. However, sending both the N and the Q via SAS results in a major service increase for SAS Phase 2 that could relieve overcrowded Bronx subways.
The first step in addressing the QB problem is resolving the Astoria problem. One way to do that is:
Reroute R trains via Astoria to Ditmars Boulevard.
Rerouting the R via Astoria addresses the loss of the N beyond peak hours. The W, if left unchanged, becomes fully contiguous with the R. Then, all W trains could run as R trains, removing all merges from the R and allowing significant service increases. Other options exist if the R and W remain separate – more on this later.
One of the main obstacles to running the R to Astoria is the lack of storage space for the R’s subway cars. The R currently serves the QB line for easy access to Jamaica Yard. A capital solution to this problem exists.
Potential capital investment: construct a new yard within the Con Edison property north of Ditmars Boulevard.
[Fig. 5] Potential yard location within the Con Edison property with a provision for a future LaGuardia Airport extension.
Building this yard solves the storage space issue, and building it inside the Con Edison property mitigates residential impacts. It also increases the Astoria line’s capacity since the current terminal is a stub with no tail tracks. Importantly, this investment also serves as an anchor for the oft-discussed Astoria line extension to LaGuardia Airport. While former governor Andrew Cuomo’s proposed LaGuardia AirTrain keeps chugging along, it does not obviate the need for the Astoria line extension.
Now, if all Broadway local service runs via Astoria, the QB corridor would lose direct access to Broadway service. A capital solution to this problem also exists.
Potential capital investment: construct an in-system transfer connecting the Queens Plaza and Queensboro Plaza stations.
This optional transfer would give Queens riders some flexibility; however, it is not trivial – Queens Plaza is underground, while Queensboro Plaza is above ground. Nevertheless, this transfer retains connectivity between the Broadway and QB lines, and serves as a key transfer point for eventual access to LaGuardia Airport.
Let us now explore de-interlining options for the QB line, and the underlying challenges in each.
Partial De-Interlining Options
Option 1a: Partial de-interlining with G extension
[Fig. 6] Overview of Option 1a.
[Fig. 7] Option 1a track map showing eliminated conflicts.
Under Option 1a, the G runs with full-length (600-foot) trains instead of 300-foot trains and extends to Forest Hills to replace the R. The F and M switch alignments west of 36th Street station, with the F running via 53rd Street and the M running via 63rd Street; this swap removes conflicts with the E. As an optional enhancement, the G and/or M can extend to Jamaica – 179th Street, allowing the F to run express east of Forest Hills.
Option 1b: Partial de-interlining with R/W swap
[Fig. 8] Overview of Option 1b.
Option 1b, like Option 1a, sends the F via 53rd Street and the M via 63rd Street to remove conflicts with the E. Rather than extending the G train, Option 1b prescribes an R/W swap in Queens, with R trains running to Astoria and the W replacing the R on the QB line. When combined with the South Brooklyn de-interlining, this option ensures all routes have direct access to at least one storage yard. An optional enhancement is extending the W to Jamaica – 179th Street to allow F express service east of Forest Hills:
[Fig. 9] Optional W train extension to Jamaica – 179th Street.
(This option does not preclude full-length trains on the G – an investment NYTIP recommends.)
Recently, I learned that the City Hall reverse curve limits Broadway local service to a maximum of 21 trains per hour (TPH). Therefore, to ensure frequent service on both the R and W lines (up to 15 TPH each, or 30 TPH combined), W trains would terminate either at Canal Street or the lower level platform at City Hall station – the latter requiring capital investment – instead of Whitehall Street – South Ferry.
Full De-Interlining Options
So long as the QB line serves more than two trunks or branches, full de-interlining is not possible. Furthermore, full de-interlining requires some level of capital investment. The Regional Plan Association, in their Save our Subways publication, tries to get around this by rerouting the M via the J line to Broad Street. This leaves QB with only the E express via 53rd Street and the F local via 63rd Street. RPA suggests doubling both E and F service to preserve service levels. NYTIP does not contemplate this option.
Before exploring full de-interlining options, let’s discuss the tunnels to Manhattan. The 53rd Street tunnel connects to 6th Avenue and 8th Avenue, while the 63rd Street tunnel connects to 6th Avenue and Broadway; the latter includes a provision for a future 2nd Avenue connection. Since the 53rd Street tunnel is the only tunnel connecting Queens to 8th Avenue, all 8th Avenue service should serve 53rd Street and all 6th Avenue service should serve 63rd Street. In addition, all Broadway local service runs via Astoria, so all W trains become R trains in this scenario. This yields two options.
Option 2: 6th Avenue service express, 8th Avenue service local
[Fig. 10] Overview of Option 2.
[Fig. 11] Option 2 track map showing eliminated conflicts.
Option 2 fully de-interlines the QB line. Under Option 2, the E runs local while the F and M run express. To ensure minimal conflict, especially given the Central Park West de-interlining, select E trains can turn at Penn Station using stub tracks due south to ensure frequent service on the 53rd Street corridor. (Some E trains could also turn at Canal Street station using another nearby stub track; however, this might create conflicts with A trains.)
Option 2 is not without its issues. One such issue is the M’s short length. All QB services use 600-foot trains except the M, which uses 480-foot trains. At present, the QB express service runs about every 2 minutes during peak hours with full-length trains. While de-interlining allows service increases on the M, its short trains result in a net loss in capacity – an untenable situation. (Running full-length M trains requires platform extensions at every station from Essex Street to Middle Village.)
Another issue is ease of access to 6th Avenue from the local stops west of Jackson Heights. Since the F and M diverge east of the next express stop (Queens Plaza), these passengers lose direct access to 6th Avenue.
Of these issues, only the latter is solvable without capital investment. From west of Jackson Heights, riders can connect to 6th Avenue by making a cross-platform transfer at 7th Avenue – 53rd Street to the B or D train.
Option 3: 6th Avenue service local, 8th Avenue service express
[Fig. 12] Overview of Option 3.
[Fig. 13] Option 3 track map showing eliminated conflicts.
Option 3 also fully de-interlines the QB line. Under Option 3, the F and M run local and the E runs express; this option doubles E service to 30 TPH peak to preserve service levels on the QB express. The E branches east of Kew Gardens – Union Turnpike station, with one branch running full time to Jamaica Center and the other part time to Jamaica – 179th Street. As with Option 2, select E trains can turn at Penn Station or Canal Street to ensure minimal conflict with A trains.
Option 3 also presents some issues:
- The F, as a local train, becomes the longest local train in the system with 54 stops end-to-end. (Most passengers don’t ride end-to-end, so this may not be too big an issue.)
- Unlike Option 2, local riders west of Jackson Heights have no opportunity to transfer to 8th Avenue service unless they ride back to Jackson Heights.
A capital solution to the second issue exists. With the R rerouted to Astoria and only 6th Avenue and 8th Avenue services on the QB line, there is now room on the 11th Street Cut west of Queens Plaza to connect the local tracks to the 63rd Street line:
[Fig. 14] Potential track connection from the 11th Street Cut to the 63rd Street line.
With this track connection, 6th Avenue trains can serve Queens Plaza directly before accessing the 63rd Street line, mitigating transfer issues and increasing service at Queens Plaza.
As of 08.29.2021, I am still leaning toward Option 1b for short-term improvement. Option 1b removes some merging conflicts on the QB line while preserving direct access to the Broadway, 6th Avenue, and 8th Avenue corridors. For long-term improvement, I am considering a modified version of Option 3 with QueensLink integration. With some slight modifications, QueensLink can work for both partial and full de-interlining on the QB corridor. I will explore this further in a future post.