UPDATE (08.29.2021): Post revised for clarity.
Welcome back to my ongoing NYTIP series! In my last post, I discussed ways to improve the Broadway and Queens Boulevard trunk lines. In this post, I will discuss the Eastern Parkway trunk line served by the 2, 3, 4, and 5 lines in Brooklyn.
Note: Click any image to enlarge.
[Fig. 1] Snippet of the NYC Subway Map showing the Eastern Parkway trunk line and branches.
The Eastern Parkway trunk line runs from Borough Hall to Crown Heights – Utica Avenue in Brooklyn. The 2 and 3 lines run local, while the 4 and 5 lines run express. West of Franklin Avenue station, the trunk is already “de-interlined” since 2 and 3 trains from Manhattan’s west side run local and 4 and 5 trains from Manhattan’s east side run express. East of Franklin Avenue station, the 2 and 5 diverge via the Nostrand Avenue branch, while the 3 and 4 continue via Eastern Parkway; the 3 runs local to New Lots Avenue, while the 4 runs express to Utica Avenue.
The current pattern constrains capacity on the 2, 3, 4, and 5 lines due to a single junction – the notorious Rogers Avenue Junction (also called Nostrand Junction):
[Fig. 2] Nostrand Junction. Source: Regional Plan Association’s Save our Subways publication.
As originally designed, Nostrand Junction had local service splitting into two branches (one via Nostrand Avenue and one continuing east on Eastern Parkway) and express service continuing via Eastern Parkway to the Utica Avenue terminal. Under the current pattern, the 5 express crosses the local tracks at grade to access the Nostrand Avenue branch. Due to this merging conflict, as well as the Flatbush Avenue – Brooklyn College terminal’s inefficient design (it wasn’t supposed to be a terminal), several peak-hour 2, 4, and 5 trains start or end at Utica Avenue or New Lots Avenue. This causes even more conflicts.
The Regional Plan Association has the right idea when they suggest sending the 2/3 via Nostrand Avenue and the 4/5 via Eastern Parkway, but there’s a problem – this pattern still requires either the 4 or the 5 to cross the local tracks to serve the local stops east of Franklin Avenue.
As such, NYTIP prescribes the following capital investment:
Rebuild Nostrand Junction as a “flying” (grade-separated) junction.
The cheapest way to do this is to adopt RPA’s suggestion, which requires short track extensions as depicted in the figure below:
[Fig. 3] Modified Nostrand Junction with new track segments. The original track map belongs to vanshnookenraggen.
With these new track connections, it is now possible to fully de-interline Eastern Parkway without merging conflicts. NYTIP recommends RPA’s suggestion – 2/3 via Nostrand Avenue, 4/5 via Eastern Parkway – and implements it as follows:
Swap the 3 and 5 lines east of Franklin Avenue.
[Fig. 4] Overview of the 3/5 swap, via Brand New Subway.
Through this swap, the 3 replaces the 5 to Flatbush Avenue – Brooklyn College, and the 5 replaces the 3 to New Lots Avenue. This enables service increases on the 2, 3, 4, and 5 lines. However, as I mentioned previously, the Brooklyn College terminal can’t handle combined 2/3 train traffic at higher frequencies due to its nature as a stub terminal with no tail tracks. Thus, fixing Nostrand Junction alone isn’t enough – one must fix the Brooklyn College terminal itself.
Potential capital investment: Construct tail tracks, or a new platform – preferably with tail tracks – at Flatbush Avenue – Brooklyn College station.
[Fig. 5] Overview of the Flatbush Avenue – Brooklyn College improvement.
While only one set of tail tracks may be enough to alleviate the Nostrand Avenue branch bottleneck, building both sets of tail tracks and the new platform allow for future extensions to both Sheepshead Bay and Kings Plaza. I’ll discuss potential Nostrand Avenue branch extensions in a future post.