The Second Avenue subway has been the aspiration of New York’s transit planners for the better part of a century. Originally envisioned as a massive trunk line that would be six tracks wide at its largest point, the current plans only call for a short “stubway” between 96 St and the Broadway Express at Lexington Av and 63 St, with future expansions north and south to be completed in the future. At first glance, the project seems like it isn’t enough; a third track at 72 St was omitted, and there are no express tracks planned for the line. However, two tracks is more than enough to provide core capacity for future expansions.
Why We Don’t Need Express Tracks
New York is unique, at least in the West, in having such a complex, extensive system of express and local lines. The system allows for a large amount of branches to converge into a tight, dense core; if the five north-south trunks were unbundled into ten north-south pairs, crosstown lines like the 7 and the L would have to make impossibly close stops to connect to all the north-south lines. In light of the fact that all the Manhattan trunk lines have express tracks, it can seem lile the Second Avenue Subway is not enough, especially when you consider that it’s meant to relieve a four-track trunk that carries more passengers than several North American systems combined. However, in this day and age, constructing express tracks is more trouble than it’s worth. Gone are the days where entire streets were ripped up and laying two or four tracks was only restricted by street width; four tracks means four TBM drives, doubling tunneling costs. Express tracks would also require bigger stations, something to avoid in a project where the most expensive parts are the stations themselves. Even if express tracks are built, they wouldn’t be particularly useful; you wouldn’t be saving a lot of time traveling from 125 St to Hanover Square, and the planned pair of tracks can actually handle quite a bit of traffic, as shown in the diagram below: In the following paragraphs, I will elaborate further on the possible expansions if the core system is built as planned.
Expansion to the North and West
The planned northern terminus of the line is at 125th and Park Avenue, with tail tracks for future expansions located as far west as Lenox and as far north as 129th and Second. This differs from previous plans, which had termini in either the Bronx or at 125th and Second. The proposed location does limit the Bronx to one new SAS service instead of two, but there isn’t enough money at this time to terminate in the Bronx, and 125th and Second is a poor location for a terminal; the area is at a higher risk of flooding, and the ramps for the Triboro Bridge start there, causing increased danger for pedestrians and potential subway riders while reducing potential development opportunities. (Note: It is assumed that two is the maximum number of services that a pair of tracks can reliably handle. Where three services run on a pair of tracks in the system, such as the 60th St tubes, congestion and cascading delays are not uncommon.)
The logical western extension would be to the West Side via 125th St. 125th St is currently a very busy, slow crosstown corridor; a crosstown connection would help redistribute traffic from the Bronx and northern Manhattan amongst the trunk lines, and would speed up commutes for many. Two options for termini exist: 125th and Broadway is the most logical one, and would provide connections to the 1 and a potential Penn Station Access station for Metro-North. Another possible terminus would be a deep-level platform at 116 St-Columbia University on the 1, to provide access to the university and potentially allow for a southern extension down the West Side.
To the north, there are three logical extensions to make, following either the Harlem Line, the Hudson Line, or the future Penn Station Access right-of-way. Of these, I would prefer to extend it via the Harlem Line ROW; since the area lost the Third Av El around it in the ’70s, the lines around it have become crowded, and restoring subway service would ease the pressure on these trains. Such a line could be built in three phases; from the existing tail tracks to 3 Av – 149 St via Third Av; from 3 Av – 149 St to Fordham Plaza; and from Fordham Plaza to either Gun Hill Road on the 2/5, or east via Pelham Parkway to Co-op City at Bay Plaza, possibly combined with an extension of the 6. The former would restore the old Third Av El’s full route, while the latter would serve as a vital crosstown connection across the Bronx that currently doesn’t exist, and would relieve one of the busiest bus routes in the system.
The 63 St Turnouts
The Second Avenue Subway, in its first phase, will connect Second Avenue to the Broadway Express going north to west. The third phase will provide a turnout connecting Second Avenue to the 63 St Tunnel’s upper level, going from south to east. The plans from the 1970s called for connecting the 63 St Tunnel to either Forest Hills or Jamaica via the LIRR’s Main Line Row, but the plans were scaled back, resulting in the current 63 St Tunnel and Archer Avenue Line stub. Any Second Avenue service would require a new pair of tracks along the Main Line, which has room for at least six tracks to Rego Park. and a tunnel from the 63 St upper level to the Main Line route. Fortunately, the latter already exists, as evidenced by this excerpt from the East Side Access EIS:
As for the pair of tracks, there would be two options. The first would be to build a pair of tracks from Long Island City to a stop on the Main Line at Rego Park via Woodside, then tunneling under Yellowstone Blvd to reach Forest Hills, connecting to the local tracks. A Second Avenue service running local from Forest Hills to 179 St would allow the F to stay on the express tracks east of Forest Hills, increasing reliability, decreasing travel times, and would pave the way for a long term extension east of 179 St; current service takes too long for extension east to be feasible. However, this plan has a major drawback – all space on the Main Line ROW between Long Island City and Woodside is taken up by the six existing LIRR tracks, so some land acquisition would be needed.
The second option would be easier from a technical standpoint, but significantly harder politically. Connecting the Port Washington branch to the 63 St upper level would require minimal new construction for significantly improved service to Corona, Eastern Queens, and Western Nassau; stations at Elmhurst (Queens Blvd & Broadway) and Corona (Junction Blvd & 108 St) would serve areas currently only serviced by overcrowded, slow feeder buses to the subway, and a grade crossing at Little Neck would have to be removed. The current Auburndale LIRR station could also be replaced by two stations at Utopia Pkwy and Francis Lewis Blvd to provide better bus connections. However, the main difficulty would be NIMBYism; it’s unclear whether even a fairly dense Nassau neighborhood such as Great Neck would be okay with the replacement of LIRR service with subway service, to say nothing of the more suburban communities east of Great Neck. If it were doable, it would be cheap, and would also make future core expansion cheaper; a short elevated line from the Astoria Line east of Queensboro Plaza to the PW tracks would provide the cross-river capacity to build the Queens Blvd Bypass.
Expansion to the South
The current plans call for a set of tail tracks south of Hanover Square as provisions for extension to Brooklyn. The most logical, cheap connection would be to the Fulton Line via the former Court St station, which currently functions as the Transit Museum. If this were to happen, it would allow for a reorganization of Fulton St service; all Eighth Avenue services would run express past Hoyt St, with C trains going to Lefferts Blvd and the A alternating between Far Rockaway and Rockaway Park, while Second Avenue trains would all run local to Euclid. This would reduce switching and improve reliability, and the provision of East Side service on the Fulton St line would also reduce loads on the Brooklyn IRT, which currently provides the only East Side service in Brooklyn. The decrease in crowding would allow for the expansion of IRT service to Nostrand Av and Av U, and the extension of the 4 down Utica Av to Kings Plaza.
In the future, it would be possible to use the storage tracks on Second Avenue between 21 and 9 Sts to provide an additional link to Brooklyn via the LES, Williamsburg, and Stuyesant Av, connecting to the Utica Av Line. Such a route would have to be studied more in depth, since the street network in the area isn’t straight, and the Second System plans for this line would require bulldozing a path for a new street. (Due to the way the Utica Av IND station is setup, a connection to the Fulton local tracks would be impossible, although it would be cheaper than a new line through Williamsburg.) As described above, the SAS provides more than enough core capacity to relieve significant sections of the subway, even without express tracks. This relief would also allow for the extension of existing overcrowded subway lines, to be detailed in a future post.