Sunnyside Junction, Redux
Seven years ago, I wrote a pair of posts about Sunnyside Yards. The first recommends the construction of a transfer station through Sunnyside Yards, in order to facilitate transfers between Penn Station- and Grand Central-bound trains. The second recommends redeveloping the yards via a deck, creating high-density residential and commercial space on a deck on top of the yard. Recent news, both about an official plan to deck the yards and about leaks that Amazon is likely to move half of its second headquarters (HQ2) to Long Island City, make a Sunnyside Junction so much more urgent.
Here is how service would look:
The color scheme is inherited from my regional rail maps (see e.g. here) but for the purposes of this post, all it means is that green and blue correspond to the inner and outer tracks of the Park Avenue, purple is East Side Access, orange corresponds to LIRR trains going to the northern pair of East River Tunnels, and red corresponds to LIRR, Metro-North Penn Station Access, and Amtrak trains going to the southern pair of East River Tunnels. No track infrastructure is assumed except what’s already in service or funded (i.e. ESA and Penn Station Access), and only two infill stations are mapped: Astoria, which would be a strong location for a stop were fares integrated with the subway and frequency high, and Sunnyside Junction.
The infill stations that are not planned
An Astoria station was studied for PSA, but was dropped from consideration for two reasons. First, the location is legitimately constrained due to grades, though a station is still feasible. And second, under the operating assumptions of high fares and low off-peak frequency, few people would use it. It would be like Wakefield and Far Rockaway, two edge-of-city neighborhoods where commuter rail ridership is a footnote compared with slower but cheaper and more frequency subway service.
A Sunnyside Junction station was in contrast never considered. There are unfunded plan for an infill station to the west of the junction, served only by Penn Station-bound trains. Such a station would hit Long Island City’s job center well, but the walk from the platform to the office towers would still be on pedestrian-hostile roads, and if there’s political will to make that area more walkable, the city might as well just redevelop Sunnyside Yards (as already planned).
The reason there was never any plan for a station can be seen by zooming in on the area I drew as a station. It’s a railyard, without streets (yet). At today’s development pattern, nobody would use it as an O&D station, even if fares and schedules were integrated with the subway. The importance of the station is as a transfer point between Grand Central- and Penn Station-bound trains. The planned developments (both HQ2 and independent city plans) makes it more urgent, since the area is relatively far from the subway, but the main purpose of the station is a better transit network, rather than encouraging development.
The main benefit of the station is transfers between the LIRR and Metro-North. While nominally parts of the MTA, the two agencies are run as separate fiefs, both of which resisted an attempt at a merger. The LIRR opposed PSA on the grounds that it had a right to any empty slots in the East River Tunnels (of which there are around 8 per hour at the peak). Governor Cuomo intervened to protect PSA from Long Island’s opposition, but in such an environment, coordinated planning across the two railroads is unlikely, and the governor would not intervene to improve the details of the ESA and PSA projects.
Network improvements
East Side Access means that in a few years, LIRR trains will split between two Manhattan destinations. Conceptually, this is a reverse-branch: trains that run on the same route in the suburbs, such as the LIRR Main Line, would split into separate routes in the city core. In contrast, conventional branching has trains running together in the core and splitting farther out, e.g. to Oyster Bay, Port Jefferson, and Ronkonkoma. Reverse-branching is extremely common in New York on the subway, but is rare elsewhere, and leads to operational problems. London’s Northern line, one of the few examples of reverse-branching on an urban subway outside New York, is limited to 26 trains per hour through its busiest trunk at the peak, and long-term plans to segregate its two city trunks and eliminate reverse-branching would raise this to 36.
To ensure LIRR trains run with maximum efficiency, it’s necessary to prevent reverse-branching. This means that each trunk, such as the Main Line and the Hempstead Branch, should only ever go to one Manhattan terminal. Passengers who wish to go to the other Manhattan terminal should transfer cross-platform. Jamaica is very well-equipped for cross-platform transfers, but it’s at a branch point going to either Manhattan or Downtown Brooklyn, without a good Penn Station/Grand Central transfer. Without a good transfer, passengers would be stuck going to a terminal they may not work near, or else be forced into a long interchange. In London the reason the Northern line is not already segregated is that the branch point in the north, Camden Town, has constrained passageways, so eliminating reverse-branching requires spending money on improving circulation.
Unlike Camden Town, Sunnyside Junction is roomy enough for cross-platform transfers. The tracks should be set up in a way that LIRR trains going to East Side Access should interchange cross-platform with PSA and Port Washington Branch trains (which should go to Penn Station, not ESA), as they do not stop at Jamaica. Penn Station-bound LIRR trains not using the Port Washington Branch, colored orange on the map, should stop at Sunnyside too, but it’s less important to give them a cross-platform transfer.
This assignment would be good not just for LIRR passengers but also for PSA passengers. Unlike on the LIRR, on the New Haven Line, reverse-branching is unavoidable. However, passengers would still benefit from being able to get on a Penn Station-bound train and connecting to Grand Central at Sunnyside. Not least, passengers on the PSA infill stations in the city would have faster access to Grand Central than they have today via long walks or bus connections to the 6 train. But even in the suburbs, the interchange would provide higher effective frequency.
The connection with development
I don’t know to what extent decking Sunnyside Yards could attract Amazon. I wrote an article last year, which died in editing back-and-forth, lamenting that New York was unlikely to be the HQ2 site because there was no regional rail access to any of the plausible sites thanks to low frequency and no through-running. Long Island City’s sole regional rail access today consists of LIRR stations on a reverse-branch that does not even go into Manhattan (or Downtown Brooklyn) and only sees a few trains per day. It has better subway access and excellent airport access, though.
However, since Sunnyside Junction is so useful without any reference to new development, the plans for decking make it so much more urgent. Sunnyside Yards are in the open air today, and there is space for moving tracks and constructing the necessary platforms. The cost is likely to be in the nine figures because New York’s construction costs are high and American mainline rail construction costs are even higher, but it’s still a fraction of what it would take to do all of this under a deck.
Moreover, the yards are not easy to deck. Let’s Go LA discussed the problem of decking in 2014: columns for high-rise construction are optimally placed at intervals that don’t jive well with railyard clearances, and as a result, construction costs are a multiple of what they are on firma. Hudson Yards towers cost around $12,000/square meter to build, whereas non-WTC commercial skyscrapers in the city are $3,000-6,000 on firma. The connection with Sunnyside Junction is that preparing the site for the deck requires extensive reconfiguration of tracks and periodic shutdowns, so it’s most efficient to kill two birds with one stone and bundle the reconfiguration required for the station with that required for the deck.
In the other direction, the station would make the deck more economically feasible. The high construction costs of buildings on top of railyards makes decking unprofitable except in the most desirable areas. Even Hudson Yards, adjacent to Midtown Manhattan on top of a new subway station, is only treading water: the city had to give developers tax breaks to get them to build there. In Downtown Brooklyn, Atlantic Yards lost the developer money. Sunnyside Yards today are surrounded by auto shops, big box retail, and missing middle residential density, none of which screams “market rents are high enough to justify high construction costs.” A train station would at least offer very fast rail access to Midtown.
If the decking goes through despite unfavorable economics, making sure it’s bundled with a train station becomes urgent, then. Such a bundling would reduce the incremental cost of the station, which has substantial benefits for riders even independently of any development it might stimulate in Sunnyside.



