UPDATE (08.29.2021): Post revised for clarity.
In my last post, I discussed the Central Park West de-interlining. Continuing with point 1 of my three-point plan to improve the NYC Subway (enhance), I’ll address the B, D, N, Q, and R lines in Brooklyn.
Note: Click any image to enlarge.
[Fig. 1] Snippet of the NYC Subway map showing the South Brooklyn subway lines.
As Figure 1 shows, many subway lines serve South Brooklyn. NYTIP addresses the B, D, N, Q, and R lines due to their complex interaction throughout the borough. Currently:
- B and D trains cross the Manhattan Bridge on the north side. The B serves the Brighton line and the D serves the 4th Avenue trunk line.
- N and Q trains cross the Manhattan Bridge on the south side. The N serves the 4th Avenue trunk line and the Q serves the Brighton line.
- The R train enters Brooklyn via the Montague Street tunnel and serves the 4th Avenue trunk line.
On the Brighton line, the B runs express and the Q runs local. On the 4th Avenue trunk line, the D and N run express and the R runs local.
As you can see, there is a lot of interlining here, which causes a lot of problems. The main culprit is the so-called Gold Street interlocking, which controls the set of switches north of DeKalb Avenue station:
[Fig. 2] Snippet of the NYC Subway track map from vanshnookenraggen showing the complex set of switches and junctions north of DeKalb Avenue.
This interlocking causes a lot of delays for B, D, N, Q, and R riders in Brooklyn – but it doesn’t have to. That’s where NYTIP comes in.
As with Central Park West, several options exist to simplify train movements in South Brooklyn, improving regularity on the B, D, N, Q, and R lines. The key is eliminating merging conflicts at the Gold Street interlocking.
Option 1: Swap the D and Q lines in Brooklyn
[Fig. 3] D/Q swap, northern segment, via Brand New Subway.
[Fig. 4] D/Q swap, southern segment.
[Fig. 5] Modified track map showing Gold Street interlocking after the D/Q swap, which eliminates all merging conflicts.
Through this swap, the D replaces the Q as the Brighton local to Coney Island, while the Q replaces the D as the 4th Avenue express to Coney Island via the West End line. This swap eliminates several conflicts between the Broadway and 6th Avenue lines in Brooklyn.
Implications for DeKalb Avenue and Atlantic Avenue
At DeKalb Avenue, the D/Q swap exchanges direct service to Canal Street and Broadway for direct service to Grand Street and 6th Avenue. The station retains direct service to Broadway via the R line, albeit through Lower Manhattan. Brighton riders desiring Broadway service can make a cross-platform transfer at DeKalb Avenue for the R, or make the longer transfer at Atlantic Avenue for the N/Q/R.
Note: If preferred, the B could run local to Coney Island and the D could run express to Brighton Beach instead.
Option 2: Swap the B and N lines
[Fig. 6] Overview of the B/N swap.
[Fig. 7] Modified track map showing Gold Street interlocking after the B/N swap, which also eliminates all merging conflicts.
In this scenario, the B replaces the N as the 4th Avenue express to Coney Island via Sea Beach, and the N replaces the B as the Brighton express to Brighton Beach. The B/N swap also removes conflicts between the Broadway and 6th Avenue lines in Brooklyn.
Back in 2004, the MTA surveyed Brighton line riders about their travel preferences and they picked Broadway over 6th Avenue by a near 2-to-1 ratio. If most Brighton line riders still prefer Broadway today, then the B/N swap works in their favor. Of course, one must weigh this against 4th Avenue/Sea Beach riders’ preferences. My perusal of OnTheMap suggests that the Canal Street corridor is a top-10 work destination for Sea Beach riders, but not for Brighton line riders. Meanwhile, on both the Brighton and Sea Beach lines, Downtown Brooklyn and West Midtown also stand out as top destinations; both the Broadway and 6th Avenue trunk lines serve these areas and are thus interchangeable.
Implications for DeKalb Avenue and Atlantic Avenue
Under this option, DeKalb Avenue essentially becomes an express stop on the Broadway trunk serving N, Q, and R trains; however, it loses direct access to 6th Avenue. At Atlantic Avenue – Barclays Center station, Brighton riders desiring 6th Avenue service must make the long transfer since there is no cross-platform opportunity.
Optional Brighton Line Improvement
Due to the Brighton line’s track layout, express trains terminate at Brighton Beach, while local trains continue to Coney Island. This could cause unbalanced ridership.
Originally, the Brighton express tracks continued to Coney Island, while the Brighton local tracks took ramps to the lower level at West 8th Street – NY Aquarium station. The Culver line connection to Coney Island severed the lower level connection – the ramps still exist but are trackless. Though reactivating the ramps isn’t desirable due to the resulting at-grade merge, there is another way to rectify this problem.
Potential capital investment: Construct a flying crossover between Sheepshead Bay and Brighton Beach stations.
[Fig. 8] Overview of the Brighton crossover. N and Q trains shown for illustrative purposes.
This optional flying crossover allows Brighton local trains to terminate at Brighton Beach, while Brighton express trains continue to Coney Island. It would make the Brighton express service more attractive and balance ridership between local and express trains.
A third option?
About 10 months after I first published this post, I wrote a follow-up post with additional commentary. That post explores de-interlining scenarios for South Brooklyn in the absence of a new yard in Astoria for R trains. I updated it after vanshnookenraggen blogged about South Brooklyn de-interlining using an existing switch provision – a provision I completely overlooked when I first drafted this post.
Utilizing that provision leads to the following service pattern:
- Brighton line
- N express to Brighton Beach, Q local to Coney Island
- 4th Avenue line
- B express to Bay Ridge (local south of 36th Street)
- D express to Coney Island via Sea Beach
- R local to Coney Island via West End
Importantly, all lines have direct access to at least one storage yard under this option. This option also lends itself to future expansion. Consider the Staten Island Subway proposals. One proposal connects to Staten Island using existing provisions south of 59th Street station in Brooklyn, while another calls for extending the Bay Ridge line from its present 95th Street terminus to Staten Island. In either case, extending an express train makes the most sense, given how far Staten Island is from the rest of the city. Vansh’s “one switch” plan is one way to catalyze such an extension.
That said, with Andrew Cuomo deposed as governor, there is a real opportunity to revive the Astoria extension to LaGuardia Airport. A key component of this extension is a new storage yard within the Con Edison property north of the Ditmars Boulevard station. Even without the airport extension, this yard would be a key component of NYTIP since the increased storage space it affords would allow service increases throughout the system.
Thus, as of 08.29.2021, I am once again leaning toward Option 1. On the Brighton line, the B would run local and the D would run express since the D is the longer of the two routes. Option 1 removes several merging conflicts while preserving transfers between the Broadway and 6th Avenue trunk lines. Note that exercising this option does not preclude building switches south of 36th Street station, as vanshnookenraggen suggests, for operational flexibility.