Category: New York

What the RER A vs. C Contrast Means for New York Regional Rail

A few weeks ago, I published a piece in City Metric contrasting two ways of through-running regional rail, which I identify with the RER A and C in Paris. The RER C (or Thameslink) way is to minimally connect two stub-end terminals pointing in opposite directions. The RER A (or Crossrail) way is to build long city-center tunnels based on urban service demand but then connect to legacy commuter lines to go into the suburbs. Crossrail and the RER A are the two most expensive rail tunnels ever built outside New York, but the result is coherent east-west regional lines, whereas the RER C is considerably more awkward. In this post I’d like to explain what this means for New York.

As I said in the City Metric piece, the current plans for through-running in New York are strictly RER C-style. There’s an RPA project called Crossrail New York-New Jersey, but the only thing it shared with Crossrail is the name. The plan involves new Hudson tunnels, but service would still use the Northeast Corridor and LIRR as they are (with an obligatory JFK connection to get the politicians interested). I alluded in the piece to RER A-like improvements that can be done in New York, but here I want to go into more detail into what the region should do.

Regional rail to Lower Manhattan

Regional rail in New York should serve not just Midtown but also Lower Manhattan. Owing to Lower Manhattan’s intense development in the early 20th century already, no full-size train stations were built there in the era of great urban stations. It got ample subway infrastructure, including by the Hudson Tubes (now PATH), but nothing that could be turned into regional rail. Therefore, regional rail plans today, which try to avoid tunneling, ignore Lower Manhattan entirely.

The Institute for Rational Urban Mobility, longtime opponent of the original ARC project and supporter of through-running, even calls for new tunnels between Hoboken and Midtown, and not between Hoboken and Lower Manhattan. I went to an IRUM meeting in 2009 or 2010, when Chris Christie had just gotten elected and it was not clear what he’d do about ARC, and when people pitched the idea, I asked why not go Hoboken-Lower Manhattan. The reply was that it was beyond the scope of “must connect to Penn Station” and at any rate Lower Manhattan wasn’t important.

In reality, while Midtown is indeed a bigger business district than Lower Manhattan, the job density in Lower Manhattan is still very high: 320,000 people working south of Worth Street in 1.9 km^2, compared with 800,000 in 4 km^2 in Midtown. Nothing in Ile-de-France is this dense – La Defense has 180,000 jobs and is said to have “over 800 jobs/ha” (link, PDF-p. 20), and it’s important enough that the RER A was built specifically to serve it and SNCF is planning a TGV station there.

Regional trains to Lower Manhattan are compelled to be more RER A-style. More tunnels are needed than at Penn Station, and the most logical lines to connect create long urban trunks. In a post from two years ago, I consistently numbered the regional lines in New York 1-5 with a non-through-running line 6:

  1. The legacy Northeast Corridor plus the Port Washington Branch, via the existing Hudson tunnels.
  2. More lines in New Jersey (some Northeast Corridor, some Morris and Essex) going to the New Haven Line via new Hudson tunnels and Grand Central.
  3. Some North Side LIRR lines (presumably just Hempstead and the Central Branch) to the Hudson Line via Penn Station and the Empire Connection; some LIRR trains should terminate at Penn Station, since the Hudson Line can’t support as much traffic.
  4. The Harlem Line connecting to the Staten Island Railway via Lower Manhattan and a Staten Island-Manhattan tunnel, the most controversial piece of the plan judging by comments.
  5. The New Jersey lines inherited from the Erie Railroad (including the Northern Branch) to the South Side LIRR (to Far Rockaway, Long Beach, and Babylon) via Lower Manhattan.
  6. More North Side LIRR lines (probably the Ronkonkoma and Port Jefferson branches) to Grand Central via East Side Access.

The Lower Manhattan lines, numbered 4 and 5, have long trunks. Line 4 is a basic north-south regional line; it’s possible some trains should branch to the Hudson Line, but most would stay on the Harlem Line, and it’s equally possible that the Hudson Line trains to Grand Central should all use line 2. Either configuration creates very high all-day frequency between White Plains and St. George, and still high frequency to both Staten Island branches, with many intermediate stations, including urban stops. Line 5 goes northwest-southeast, and has to have, at a minimum, stops at Pavonia, Lower Manhattan, Downtown Brooklyn, and then all the LIRR Atlantic Branch stops to and beyond Jamaica.

More stops within new tunnels

Even new tunnels to Midtown can be built with the RER A concept in mind. This means more stations, for good connections to existing subway and bus lines. This is not superficially obvious from the maps of the RER A and C: if anything, the RER C has more closely-spaced stops within Paris proper, while the RER A happily expresses from La Defense to Etoile and beyond, and completely misses Metro 5 and 8. Crossrail similarly isn’t going to have a transfer to every Underground line – it’s going to miss the Victoria and Piccadilly lines, since connecting to them would have required it to make every Central line stop in the center of London, slowing it down too much.

However, the important feature of the RER A is the construction of new stations in the new tunnels – six of them, from La Defense to Nation. The RER C was built without any new stations, except (later) infill at Saint-Michel, for the transfer to the RER B. The RER C’s urban stations are all inherited legacy stations, even when underground (as some on the Petite Ceinture branch to Pontoise are), since the line was built relatively cheaply, without the RER A’s caverns. This is why in my City Metric piece, I refer to the RER B as a hybrid of the RER A and C approaches: it is a coherent north-south line, but every station except Saint-Michel is a legacy station (Chatelet-Les Halles is shared with the RER A, Gare du Nord is an existing station with new underground platforms).

With this in mind, there are several locations where new regional rail tunnels in New York could have new stations. I wrote two years ago about Bergenline Avenue, within the new Hudson tunnels. The avenue hosts very high bus and jitney frequency, and today Manhattan-bound commuters have to go through Port Authority, an obsolete structure with poor passenger experience.

Several more locations can be identified. Union Square for line 4 has been on the map since my first post on the subject. More stations on line 5 depend on the alignment; my assumption is that it should go via the approach tracks to the Erie’s Pavonia terminal, but if it goes via Hoboken then there should be a station in the Village close to West 4th Street, whereas if it goes via Exchange Place then there should be a station at Journal Square, which is PATH’s busiest New Jersey station.

On lines 4 and 5, there are a few additional locations where a station should be considered, but where there are strong arguments against, on the grounds of speed and construction cost: Brooklyn Heights, Chinatown (on line 5 via Erie, not 4), a second Lower Manhattan station on line 4 near South Ferry (especially if the main Lower Manhattan station is at City Hall rather than Fulton Street).

There are also good locations for more stations on the Metro-North Penn Station Access routes, both the New Haven Line (given to line 1) and the Hudson Line (given to line 3). Current plans for Penn Station Access for the New Haven Line have four stations in the Bronx, but no connection to Astoria, and a poor connection to the Bx12 buses on Fordham Road. A stop on Pelham Parkway would give a stronger connection to the Bx12 than the Coop City station, which the Bx12 reaches via a circuitous route passing through the 6 train’s northern terminus at Pelham Bay Parkway. Astoria has been studied and rejected on two grounds: one is construction difficulties, coming from the constrained location and the grade; the other is low projected ridership, since current plans involve premium fares, no fare integration with the subway and buses, and low off-peak frequency. The first problem may still be unsolvable, but the second problem is entirely the result of poor industry practices.

On the Empire Connection, there are plans for stops at West 62nd and West 125th Street. It is difficult to add more useful stations, since the line is buried under Riverside Park, far from Upper West Side and Washington Heights development. The 125th Street valley is one of few places where urban development reaches as far west as the Empire Connection. That said, Inwood is low-lying and it’s possible to add a station at Dyckman Street. In between, the only semi-plausible locations are 145th Street or 155th-158th (not both, they’re too close), and even those are marginal. All of these neighborhoods, from West Harlem north, have low incomes and long commutes, so if it’s possible to add stations, Metro-North should just do it, and of course make sure to have full fare integration with the subway and buses. The one extra complication is that there are intercity trains on this line and no room for four-tracking, which limits the number of infill stops that can support high frequency (at worst every 10 minutes).

Infill stops on existing lines

The existing regional lines in New York have very wide stop spacing within the city. It’s a general feature of North American commuter rail; I wrote about it 5 years ago in the context of Chicago, where Metra is even more focused on peak suburb-to-CBD commutes than the New York operators. In most North American cities I heartily endorse many infill stops on commuter rail. I have a fantasy map for Los Angeles in which the number of stops on inner commuter rail lines triples.

However, New York is more complicated, because of the express subway lines. In isolation, adding stops to the LIRR west of Jamaica and to Metro-North between Harlem and Grand Central would be a great idea. However, all three lines in question – Metro-North, the LIRR Main Line, and the Atlantic Branch – closely parallel subway lines with express tracks. It’s still possible to boost urban ridership by a little by having a commuter rail stop for each express subway stop, which would mean 86th and 59th Streets in Manhattan and Utica Avenue in Brooklyn, but the benefits are limited. For this reason, my proposed line 4 tunnel from Grand Central down to Lower Manhattan has never had intermediate stations beyond Union Square. For the same reason, while I still think the LIRR should build a Sunnyside Junction station, I do not endorse infill elsewhere on the Main Line.

That said, there are still some good candidates for infill. Between Broadway Junction and Jamaica, the LIRR parallels only a two-track subway line, the J/Z, which is slow, has poor connections to Midtown (it only goes into Lower Manhattan), and doesn’t directly connect Jamaica with Downtown Brooklyn. The strongest location for a stop is Woodhaven Boulevard, which has high bus ridership. Lefferts is also possible – it hosts the Q10 bus, one of the busiest in the borough and the single busiest in the MTA Bus system (most buses are in the New York City Transit bus division instead). It’s 4.7 km from Woodhaven to Broadway Junction, which makes a stop around Logan or Crescent feasible, but the J/Z is much closer to the LIRR west of Crescent Street than east of it, and the A/C are nearby as well.

Another LIRR line that’s not next to a four-track subway is the inner Port Washington Branch. There are no stops between the Mets and Woodside; there used to be several, but because the LIRR had high fares and low frequency, it could not compete once the subway opened, and those stations all closed. There already are plans to restore service to Elmhurst, the last of these stations to be closed, surviving until 1985. If fares and schedules are competitive, more stations are possible, at new rather than old locations: Queens Boulevard with a transfer to a Triboro RX passenger line, and two Corona stops, at Junction Boulevard and 108th Street. Since the Port Washington Branch is short, it’s fine to have more closely-spaced stops, since no outer suburbs would suffer from excessive commutes as a result.

Beyond Jamaica, it’s also possible to add LIRR stops to more neighborhoods. There, the goal is to reduce commute length, which requires both integrated fares (since Southeast Queens is lower middle-class) and more stops. However, the branches are long and the stop spacing is already not as wide as between Jamaica and Broadway Junction. The only really good infill location is Linden Boulevard on the Atlantic Branch; currently there’s only a stop on the Montauk Line, farther east.

In New Jersey, the situation is different. While the stop spacing east of Newark is absurdly long, this is an artifact of development patterns. The only location that doesn’t have a New Jersey Transit commuter rail stop that could even support one is Harrison, which has a PATH station. Additional stations are out of the question without plans for intense transit-oriented development replacing the warehouses that flank the line. A junction between the Northern Branch and line 2, called Tonnelle in my post on The Transport Politic from 2009, is still feasible; another stop, near the HBLR Tonnelle Avenue station, is feasible on the same grounds. But the entire inner Northern Branch passes through hostile land use, so non-junction stations are unlikely to get much ridership without TOD.

West or south of Newark, the land use improves, but the stop spacing is already quite close. Only two additional locations would work, one on the Northeast Corridor near South Street, and one on the Morris and Essex Lines at the Orange Street stop on the Newark Subway. South Newark is dense and used to have a train station, and some area activists have hoped that plans to extend PATH to the airport would come with a South Street stop for additional urban service. At Orange Street the land use isn’t great, since a highway passes directly overhead, but the Newark Subway connection makes a station useful.

Finally, in Manhattan, the East River Tunnels have four tracks, of which Amtrak only needs two. This suggests an infill East Side station for the LIRR. There are strong arguments against this – namely, cost, disruption to existing service, and the fact that East 33rd Street is not really a prime location (the only subway connection there is the 6). On the other hand, it is still far denser than anywhere in Brooklyn and Queens where infill stations are desirable, and the 6’s ridership at 33rd Street is higher than that of the entire Q10 or Bx12.


The RER A and Crossrail are not minimal tunnels connecting two rail terminals. They are true regional subways, and cost accordingly. Extracting maximum ridership from mainline rail in New York requires building more than just short connections like new Hudson tunnels or even a Penn Station-Grand Central connection.

While some cities are blessed with commuter rail infrastructure that allows for coherent through-service with little tunneling (like Boston) or no tunneling at all (like Toronto), New York has its work cut out for it if it wants to serve more of the city than just Jamaica and the eastern Bronx. The good news is that unlike Paris and London, it’s possible to use the existing approaches in Brooklyn and New Jersey. The bad news is that this still involves a total of 30 km of new tunnel, of which only about 7 are at Penn Station. Most of these new tunnels are in difficult locations – underwater, or under the Manhattan CBD – where even a city with reasonable construction costs like Paris could not build for $250 million per km. The RER A’s central segment, from Nation to Auber, was about $750 million/km, adjusted for inflation.

That said, the potential benefits are commensurate with the high expected costs. Entire swaths of the city that today have some of the longest commutes in the United States, such as Staten Island and Eastern Queens, would be put within a reasonable distance of Midtown. St. George would be 6 minutes from Lower Manhattan and perhaps 14 from Grand Central. Siting infill stations to intersect key bus routes like Bergenline, Woodhaven, and Fordham, and making sure fares were integrated, would offer relatively fast connections even in areas far from the rail lines.

The full potential of this system depends on how much TOD is forthcoming. Certainly it is easier to extract high ridership from rapid transit stations that look like Metrotown than from ones that look like typical suburban American commuter rail stops. Unfortunately, New York is one of the most NIMBY major cities in the first world, with low housing growth, and little interest in suburban TOD. Still, at some locations, far from existing residential development, TOD is quite likely. Within the city, there are new plans for TOD at Sunnyside Yards, just not for a train station there.

The biggest potential in the suburbs is at White Plains. Lying near the northern terminus for most line 4 trains, it would have very good transit access to the city and many rich suburbs in between. It’s too far away from Manhattan to be like La Defense (it’s 35 km from Grand Central, La Defense is 9 km from Chatelet-Les Halles), but it could be like Marne-la-Vallee, built in conjunction with the RER A.

Right now, the busiest commuter lines in New York – both halves of the Northeast Corridor and the LIRR Main Line – are practically intercity, with most ridership coming from far out. However, it’s the inner suburbs that have the most potential for additional ridership, and middle suburbs like White Plains, which is at such distance that it’s not really accurate to call it either inner or outer. The upper limit for a two-track linear route with long trains, high demand even in the off-peak hours, and high ridership out of both ends, is around a million riders per weekday; higher ridership than that is possible, but only at the levels of overcrowding typical of Tokyo or Shanghai. Such a figure is not out of the question for New York, where multiple subway lines are at capacity, especially for the more urban lines 4 and 5. Even with this more limited amount of development, very high ridership is quite likely if New York does commuter rail right.

Express Airport Connectors are a Scourge of Public Transit

Earlier this month, Andrew Cuomo unveiled a proposal to spend $10 billion on improvements to JFK Airport, including new terminals, highway expansion, and public transit access. I encourage readers to look at the plan: the section on highways proposes $1.5-2 billion in investment including adding lanes to the Van Wyck Expressway and to on-ramps, and has the cheek to say that this will reduce fuel consumption and greenhouse gas emissions. This while the section on mass transit gives it short shrift, only proposing superficial improvements to the AirTrain; in the unlikely the case that this is built, highway mode share will grow and transit mode share will fall. Put in plainer terms, the environmental case for the plan includes fraud.

However, this is not really the topic of this post. That Andrew Cuomo lies to the voters and doesn’t care about good transportation is by now a dog-bites-man story. Instead, I want to focus a little on a throwaway line in the plan, and more on the Regional Plan Association’s reaction. The throwaway line is that almost every major world airport has a one-seat train ride to city center, and by implication, so should JFK.

As an organization dedicated to environment-friendly public transit, the RPA should have made it very clear it opposes the plan due to its low overall transportation value and its favoring of highways over transit. Instead, the RPA immediately launched a brief detailing possible new airport connectors between JFK and Manhattan. The RPA has a lot of good technical people, and its list of the pros and cons of each option is solid. It correctly notes that using the LIRR and Rockaway Beach Branch would compete for traffic with LIRR trains serving Long Island, although it doesn’t mention associated problems like low frequency. The brief is based on prior RPA proposals, but the timing, just after Cuomo came out with his announcement, suggests an endorsement. There are several intertwined problems here:

There is no no-build option

A good study for public transit should not only consider different alignments and service patterns, but also question whether the project is necessary. The US requires environmental impact statements to include a no build option; European countries require a cost-benefit analysis, and will not fund projects with a benefit/cost ratio under 1.2, because of cost escalation risk.

The RPA study does not question whether a one-seat ride from JFK to Manhattan is necessary or useful. It assumes that it is. Everything else about the study follows from that parameter. Thus, it considers entirely express plans, such as the LIRR option, alongside local options. Everything is subsumed into the question of connecting JFK to Manhattan.

One of the alignments proposed is via the LIRR Atlantic Branch and Second Avenue Subway, which the RPA has long believed should be connected. The brief says that it would be slow because it would have to make many local stops; I’ll add that it would serve Midtown, where nearly all the hotels are, via a circuitous alignment. But with all these stops on the way, shouldn’t this be considered as primarily a new trunk line connecting Eastern Brooklyn with Second Avenue? The question of whether the eastern terminus should be Jamaica or JFK must be subsumed to a study of this specific line, which at any rate is unlikely to offer faster service to JFK than the existing AirTrain-to-E option. After all, the most optimistic ridership projection for a JFK connector is maybe 40,000 users per day, whereas the projection for the full Second Avenue Subway is 500,000. I don’t think a Second Avenue-Atlantic Branch connection is warranted, but if it is, the question of whether to serve JFK at the end is secondary.

Express airport connectors are a fetish

I lived in Stockholm for two years, where I went to the airport exclusively using the Arlanda Express, a premium express link running nonstop between the airport and city center. I imagine many visitors to Stockholm use it, are satisfied, and want to replicate it in their own cities.

Unfortunately, such replications miss something important: any air-rail link must go to the areas that people are likely to want to connect to. For locals who wish to travel to the airport, this means good connections to the local transit network, since they are likely to come from many neighborhoods. Not even a small city like Stockholm worries about providing rich areas like Vasastan and Roslag with a one-seat ride. For visitors, this means a one-seat ride to where the hotels are.

Stockholm is a largely monocentric city, with one city center where everything is. (It has an edge city in Kista, with more skyscrapers than Central Stockholm, but Kista can’t be reasonably connected to the airport). The situation in other cities is more complicated. And yet, express air links prioritize serving a big train station even if it’s poorly connected to the transit network and far from the hotels. Let us consider London and Paris.

In London, the five-star hotels cluster around the West End. Only two are at Paddington Station, and only a few more are an easy walking distance from it. This is where the Heathrow Express and the slower Heathrow mainline trains go. No wonder the Heathrow Express’s mode share, as of 2004, is 9%, whereas other Heathrow connections, mainly the Piccadilly line, total 27% (source, PDF-p. 28). The Piccadilly line beautifully passes through the parts of the West End with the largest concentration of hotels, and last time I was in London, I chose it as my Heathrow connection. Nonetheless, the government chose to build the Heathrow Express.

In Paris, the five-star hotels cluster in the west of the city as well, in the 8th arrondissement. The current airport connection is via the RER B, which offers express service in the off-peak when there’s capacity, but not in the peak, when there isn’t. Even so, it is a local commuter rail service, with good connections to the city transit system, and a two-seat ride to the 8th. Because of slow perceived speeds, the state is planning to build an express connector, originally planned to open in 2015 but since delayed to 2023. The express connector will dump passengers at Gare de l’Est, with no hotels within walking distance, no access to Metro lines serving the hotel clusters (Metro 7 does so peripherally, M4 and M5 not at all), and a long walk to the RER for passengers wishing to connect to longer-range destinations such as parts of the Left Bank.

I bring this up to show that the idea of the express air-rail link is a fetish rather than a transportation project, and by analogy, so is the one-seat ride. There is value in faster service and in minimizing the number of transfers, but express airport connectors attempt both even at the cost of building a line that doesn’t go where people want to go.

Ultimately, Cuomo doesn’t care about good transit

Cuomo has many concerns. The chief one is most likely winning the 2020 presidential primary. He has been running for president since the moment he was elected, and many of his policies – gay marriage, the feuds with Bill de Blasio, the desperate attempt to build shiny infrastructure with his name on it – are best viewed through that lens. To the extent that he is not running for president, he has attempted to cement absolute power within the state. He backed a palace coup in the State Senate that secured a Republican(-ish) majority even though the Democrats won most seats; a Democratic majority would be led by a different faction of the party, one more beholden to Democratic interest groups, and might send Cuomo bills that he would lose political capital if he either signed or vetoed them.

This is why I keep giving him as an example of an autocrat in various posts; here is the major takedown, but see also here. Autocrats are always bad for the areas that they govern, which as two separate implications. The first is that their choice of spending priorities is compromised by the need to expand their own power and glory: even if you believe that New York needs $1.5-2 billion in new highway spending, is the Van Wyck really the best place for it?

The second and worse implication is that it is hard for outside groups to convince autocrats to do better. Autocrats don’t have to listen; if they did, they would be democratic leaders. Cuomo happens to be an anti-transit autocrat, and this means that pro-transit groups in New York need to view him as an obstacle and work to weaken him, rather than to ask him to please consider their plans for an air-rail link.

The difficulty is that, precisely because local- and state-level democracy in the US is so weak, it is difficult for issue-oriented groups to go out and oppose the governor. Planners in Democratic cities are hesitant to attack budget-cutting Republican governors like Charlie Baker and Larry Hogan; attacking Democratic governors like Cuomo is a nonstarter. Nonetheless, the RPA needs to understand that it needs to oppose governments hostile to public transit rather than ask them to improve. When Cuomo proposes a bad transportation project, say “no” and move on to more important things; don’t try to work with him, because nothing good can come of that.

Second Avenue Subway Phase 2 to Cost $6 Billion

Since the 2015-9 capital plan, the New York MTA had been including the second phase of Second Avenue Subway in its capital plan, without a clear estimate of its projected cost. The rumors said the cost would be about $5 billion. A new media story finally gives an official cost estimate: $6 billion. The total length of the project, from 96th Street and 2nd Avenue to 125th Street and Lexington, is about 2.7 km. At $2.2 billion per km, this sets a new world record for subway construction costs, breaking that of the first phase of the same line, which only cost $1.7 billion per km. See a compendium of past posts here to look how these projects stack up. For people not interested in combing through multiple old posts of mine, the short version is that outside the Anglosphere, subway tunnels typically cost $100-300 million per km, with outliers in both directions, but even inside the Anglosphere, costs are in the mid-to-high hundreds of million per km.

In some way, the high cost of SAS phase 2 is more frustrating than that of phase 1. This is because 1 km of the 2.7 km of route preexists. SAS construction began in the 1970s, but was halted due to New York’s financial crisis. In East Harlem, some actual tunnel segments were dug, roughly between the proposed station locations at 96th, 106th, 116th, and 125th Streets; Wikipedia has a more detailed list. Construction of phase 2 thus involves just the stations, plus a short bored segment under 125th Street to get from Second Avenue to Lexington, for a connection to the 4, 5, and 6 trains.

Not having to build tunnels between the stations is beneficial, not as a cost saver in itself but as a way to reduce station costs. In phase 1, it appears that most costs were associated with the stations themselves; if I remember correctly, the cost breakdown was 25% for each of three new stations, and 25% for the tunnels in between. The reason is that the stations are quite deep, while the tunneling in between is bored, to reduce surface disruption. Deep stations are more expensive because they require more excavation, while tunnel boring costs depend more on soil type and how much infrastructure is in the way than on depth. Counting the extra expense of stations, bored subways cost more per km than cut-and-cover subways, but create less surface disruption away from station sites, which is why this method was chosen for phase 1. In contrast, in phase 2, most construction is stations, which would favor a shallow cut-and-cover solution.

Unfortunately, according to rumors, it appears that the MTA now judges it impossible to use the preexisting tunnels in phase 2. If this is true, then this would explain the higher cost (though it would justify $400 million per km, not $2.2 billion): they’d have to build underneath those tunnels. But if this is true then it suggests severe incompetence in the planning stage, of the kind that should get senior employees fired and consultants blacklisted.

The reason is that Second Avenue Subway was planned as a single line. The Environmental Impact Statement was for the full line, including the proposed construction techniques. The phasing was agreed on by then; there was only enough state money for phase 1. This isn’t an unexpected change of plans. I’d understand if in the 2000s it was found that tunnels from the 1970s were not usable; this happened further south, in phase 4, where a preexisting tunnel under Chrystie Street was found to be difficult to use. But in the 2000s the SAS studies signed off on using the tunnels in Harlem, and what seems to be happening is that phase 1, built according to the specifications of the same study, is too deep for using the tunnels.

At $6 billion, this line shouldn’t be built. I know that it goes to a low-income, underserved neighborhood, one that I’ve attacked New York before for taking years to equip with bike lanes (scroll down to my comments here). But the ridership projection is 100,000 per weekday, and $60,000 per weekday rider is too much. Phase 1, providing an underrated east-west connection and serving a denser neighborhood, is projected to get 200,000, for a projection of around $25,000 per weekday rider, which isn’t terrible, so it’s a justified project even if the costs could be an order of magnitude lower.

Were costs lower, it would be possible to build subways to many more low-income neighborhoods in New York. A 125th Street crosstown line, extending phase 2 of SAS, would provide Harlem with crucial east-west connectivity. Subways under Nostrand and Utica Avenues would serve a mixture of working- and middle-class neighborhoods in Brooklyn. A subway under Northern Boulevard in Queens, connecting to phases 3 and 4 of SAS, would serve one of the poorest parts of Queens. A network of tramways would improve surface transit in the South Bronx. Triboro Line would connect poor areas like the South Bronx and East New York with richer ones like Astoria. New York could achieve a lot, especially for its most vulnerable residents, if it could construct subways affordably.

But in a world in which subways cost $60,000 per weekday rider and $2.2 billion per km, New York cannot extend the subway. If it has money in its budget for investment, it should look into things other than transportation, such as social housing or schools. Or it could not borrow money at all to pay for big projects, and in lieu of the money spent on interest, reduce taxes, or increase ongoing social spending.

Given persistent high costs, I would recommend shelving SAS and future rail extensions in New York, including the Gateway tunnel, until costs can be drastically cut. There’s no shortage of worthy priorities for scarce budget in New York, both city and state. Health care in the US is too expensive by a factor of 2, not 10, and transfer payments have near-100% efficiency no matter what; it’s possible to exhaust the tax capability of a state or city just on these two items. Perhaps the need to compete with other budget priorities would get the MTA to cut waste.

Excuses for High Construction Costs

I have written many posts about international differences in subway construction costs. They’ve gotten a lot of media attention, percolating even to politicians and to a team of academics. Against this positive attention, there have been criticisms. Three come to mind: the numbers are incorrect, costs do not matter, and the comparisons are apples-and-oranges. The first criticism depends entirely on whether one disbelieves figures given in high-quality trade publications, government websites, and mass media. The second criticism I addressed at the beginning of the year, comparing the extent of subway construction in Sweden and the US. Today, after hearing people invoke the third criticism on social media to defend Ed Glaeser’s remark that it’s possible to cut US construction costs by 10% but not 75%, I want to explain why the comparisons I make do in fact involve similar projects. Some of the specific criticisms that I’m comparing apples and oranges are pure excuses, borne out of ignorance of how difficult certain peer subway tunneling projects have been.

First, let us go back to my first post on the subject: I was comparing New York, where I was living at the time, with Tokyo, Seoul, Singapore, London, Paris, Berlin, Amsterdam, Copenhagen, Zurich, Madrid, Milan, Barcelona, and Naples – all well-known global cities. Going even farther back, before I started this blog in 2011, I first saw the difference between New York and Tokyo in 2008 or 2009, and then looked up figures for London, Paris, and Berlin in late 2009. I was focusing on infill projects in the biggest cities in the first world, specifically to preempt claims that New York is inherently more expensive because it’s bigger and richer than (say) Prague. Until I started looking at third-world construction costs, I thought they’d be lower; see for example what I wrote on the subject in 2009 here.

I bring this history up to point out that at first, I was exceptionally careful to pick projects that would pass any exceptionalist criticism portraying New York or the US in general as harder to build in. With a more complete dataset, it’s possible to rebut most of the big criticisms one could make under the apples-and-oranges umbrella.

Labor Costs

Labor costs are of course high in New York, but also in many of the other cities on my list. The best comparable sources I can find for income in the US and Europe cite income from work (or total income net of rent and interest): see here for US data and look under “net earnings,” and here for EU data. Ile-de-France is about as rich as metro New York, and London and Stockholm are only slightly poorer, all after PPP adjustment.

Moreover, within countries, there’s no obvious relationship between income and construction costs. The US is somewhat of an exception – Los Angeles appears to have the cheapest subways, and is also the poorest of the major cities – but elsewhere, this effect is muted or even reversed. The factor-of-2 difference in income between Lombardy and Campania has not led to any construction cost difference between Milan and Naples. In France, a comparative analysis of tramway costs, showing some but not all lines, fails to find significant differences between Paris and many provincial cities, with far lower regional incomes; moreover, this list omits Lyon, the richest provincial city, where the line for which I can find reliable cost data would be squarely in the middle of the national list in cost per km.

Finally, between countries, the correlation between construction cost and wealth seems weak when one excludes the US. My analysis of this is a subjective impression from looking at many case studies; David Schleicher and Tracy Gordon, formally analyzing a dataset with a large overlap with mine, find a positive but weak correlation. PPP-adjusted costs tend to be much more consistent across countries of varying income levels than GDP-adjusted costs; the latter statistic would exhibit a vast gap between the construction costs of much of Europe and those of high-cost poor countries like India and Bangladesh, the former statistic would show them to be not too different.

What is true is that New York specifically seems to have labor regulations that reduce productivity. Little of this is in citable, reputable sources, but comes from quotes given to me from people involved in the industry. One example given by Michael Horodniceanu, president of MTA Capital Construction, is of a certain task involving tunnel-boring machines, which is done by 9 people in Madrid and 24 in New York. However, there’s a chasm between the claim that the US is more expensive because it pays first-world wages and the claim that there are specific labor regulations in the US in general or New York in particular that raise construction costs. The latter claim is if anything optimistic, since it suggests it is possible to improve labor productivity with rule changes and automation.

Land Costs and NIMBYs

People whose only experience with major infrastructure projects outside the US is reading about China think that the US has a NIMBY-prone process, driving up land acquisition costs. Too many proponents of high-speed rail think that it should go in freeway medians to save on such costs; Hyperloop proponents even claim that the proposed system’s fully elevated nature is a plus since it reduces land footprint. The reality is the exact opposite.

In Japan, as Walter Hook explains in a Transportation Research Board paper from 1994, urban landowners enjoy strong property rights protections. This drives up the cost of construction: land acquisition is 75-80% of highway construction cost in Japan, compared with 25% in the US; for rail, both sets of numbers are lower, as it requires narrower rights-of-way than highways. In Japan, acquiring buildings for eminent domain is also quite difficult, unlike in the US. Tokyo is toward the upper end of rail construction costs outside the Anglosphere, and the smaller cities in Japan seem to be at best in the middle, whereas the Shinkansen’s construction cost seems relatively low for how much tunneling is required.

In the last twenty years, land prices have increased in the US cities that build the most subways, including New York, San Francisco, and Los Angeles. However, Second Avenue Subway had few demolitions, for ventilation rather than carving a right-of-way. New York and other North American cities benefit from having wide arterial streets to dig subways under; such streets aren’t always available in Europe and Japan.

Urban Density

Manhattan is dense. Thus one of the excuses for high construction costs is that there’s more development near under-construction subway routes than in other cities. I say excuse and not reason, because this explanation misses three key facts:

1. While New York is very dense, there exist other cities that are about equally dense. Paris has the same residential density as Manhattan, both around 26,000 people per km^2. The wards of Tokyo where infill subways are built are less dense, but not by much: Toshima, Shinjuku, and Shibuya, where the Fukutoshin Line passes, are collectively at 18,500/km^2. Athens proper has about 17,000/km^2, and most of the under-construction Line 4 is in the city proper, not the suburbs. Barcelona has 16,000/km^2. Paris, Athens, and Barcelona do not appear to have much higher construction costs than lower-density Continental cities like the cities of Germany or Scandinavia.

2. Suburban subway extensions in the US are quite expensive as well. The projected cost of BART to San Jose is around $500 million per underground km; Boston’s Green Line Extension, in a trench next to a mainline railroad, is currently around $400 million, so expensive it was mistakenly classified as a subway in a Spanish analysis (PDF p. 34) even before the latest cost overrun; Washington’s Silver Line, predominantly in a suburban freeway median, with little tunneling, is around $180 million per km. It is to be expected that a suburban subway, let alone a suburban light rail line, should be cheaper than city-center infill; what is not to be expected is that an American suburban light rail line should cost more than most infill subways in Europe.

3. Density by itself does not raise construction costs, except through its effects on the built form and on land costs. Land costs, as described in the previous section, are not a major factor in US construction costs. Built form is, but Second Avenue Subway passes under a wide arterial street, limiting not only takings but also the quantity of older infrastructure to cross. Tunnels that cross under entire older subway networks, such as Tokyo’s Fukutoshin and Oedo Lines, Paris Metro Line 14 and the extension of the RER E to the west, Barcelona Lines 9 and 10, and London’s Crossrail and Jubilee Line Extension, naturally have higher construction costs; in some cases, it required careful design to thread these lines between older tunnels, with only a few centimeters’ worth of clearance. The 7 extension has no more difficult construction than those lines, and Second Avenue Subway is if anything easier. Even the future phase 3, crossing many east-west subways in Midtown, mostly involves overcrossings, as those east-west subways are quite deep at Second Avenue to go under the East River.

General Construction Difficulties

People who defend New York’s high construction costs as reasonable or necessary like to point out geological difficulties; I recall seeing a few years ago a reference to an archeological site in Harlem as evidence that New York has unique difficulties. As with the other excuses, these problems are far less unique than New Yorkers think, and in this case, New York is actually much easier than certain other cases.

The point here is that the presence of urban archeology is indeed a massive cost raiser. In cities with significant preindustrial cores, lines passing through old sites have had to be built delicately to avoid destroying artifacts. For examples, consider Marmaray in Istanbul, Rome Metro Line C, and multiple lines in Athens and Mexico City. While Turkish construction costs are generally low, Marmaray was about $400 million per km, and a project manager overseeing construction said, “I can’t think of any challenge this project lacks.” Rome Metro Line C has been plagued with delays and is around twice as expensive per km as recent lines in Milan and Naples. In Paris, Metro 14 ran into medieval mines at its southern extremity during construction, leading to a cave-in at a kindergarten; a suburban extension of Metro 4 required some work on the mines as well.

Such artifacts exist in New York, but generally only at its southern end, which was settled first. The Upper East Side urbanized in the late 19th century. It does not have the layers of fragile artifacts that cities that were already large in the Middle Ages were, let alone cities from Antiquity like Rome and Byzantium.

Against this, there is the real fact that Manhattan’s rock is schist, which is hard to tunnel through since its quality is inconsistent (see e.g. brief explanation in a New York Times article from 2012). The rock itself is not too different from the granite and gneiss of Stockholm, but is at times more brittle, requiring more reinforcement; contrary to what appears to be popular belief, the problem isn’t that schist is hard (gneiss is even harder), but that it is at times brittle. That said, by the standards of medieval Parisian mines and Roman ruins, this does not seem like an unusual imposition. What’s more, phase 2 of Second Avenue Subway appears to be in Inwood marble rather than Manhattan schist, and yet the projected construction costs per km appear to be even higher; the rumors I have seen on social media peg it at $5 billion for about 2.7 km, of which about 1 km preexists.

There is Always an Excuse

The sharp-eyed reader will notice that with the possible exception of Paris Metro 14, the projects I am positively comparing to American subways are only discussed in one or two of the four above items – labor costs, land costs, density, and geology and archeology. It’s always possible to excuse a particular high-cost line by finding some item on which it differs from other lines. There aren’t a lot of subway lines under construction in the world right now, complicating any attempt at a large-N study. David Schleicher and Tracy Gordon have looked at a few possible correlates, including GDP per capita, corruption perception, and whether the country uses English common law, but there aren’t enough datapoints for a robust multivariate analysis, only for univariate analyses one correlate at a time.

Were the cost difference smaller, I might even be inclined to believe these excuses. Perhaps New York really does have a unique combination of high density, high wages, difficult rock, and so on. If Second Avenue Subway cost $500 million per km, and if above-ground rail lines elsewhere in the US cost like above-ground rail lines in the rest of the developed world, I would at most hesitantly suggest that there might be a problem in forums with plenty of experts who could give plausible explanations. But the actual cost of subways in New York is $1.5 billion per km, and proposed future lines go even higher; meanwhile, multiple at-grade and elevated US lines cost 5-10 times as high as European counterparts. That New York specifically has a factor-of-10 difference with cities that share most of its construction difficulties suggests that there really is a large problem of waste.

New Yorkers tend to think that New York is special. This is not true of the denizens of every city, though London and Paris both seem to share New York’s pathology. The result is that many New Yorkers tend to discount such cross-city comparisons; who am I to put New York on the same list as lesser cities like Stockholm and Barcelona? I was affected by this mentality enough to begin my comparisons with the few cities New York could not denigrate so well. But with further investigation of what makes some subway tunnels more difficult than others, we can dispense with this chauvinism and directly discuss commonalities and differences between various cities. That is, those of us who care about good transit can have this discussion; the rest can keep their excuses.

When Buses are a Poor Guide to Corridor Demand

Vancouver is going to open the Evergreen Line at the end of the year, an 11-km SkyTrain branch to Coquitlam with a projected ridership of 70,000 per weekday; current ridership on the B-line bus paralleling the route, the 97, is 11,000, the 20th busiest citywide (see data here).

New York is going to open the first phase of Second Avenue Subway at the end of the year or early next year, a total of 4 km of new route with projected ridership of 200,000 per day (see pp. 2-3). The bus running down First and Second Avenues, the M15, has 46,000 weekday riders, trading places with two other routes for first citywide, but first phase only covers a quarter of the route, and the ridership projection in case the entire Second Avenue Subway is built is 560,000; nobody expects the other two top bus routes in New York, the B46 on Utica and the Bx12 on Fordham, to support such ridership if they’re ever replaced with subways.

In Boston, the Green Line Extension northwest in Somerville is projected to have 52,000 weekday riders by 2030. There is no single parallel bus, but a few buses serve the same area: the 101 with 4,800 weekday riders, the 89 with 4,200, the 88 with 4,100, and the 87 with 3,800 (all bus ridership data is from the Bluebook, PDF-pp. 48-54); the busiest of these ranks 28th regionwide.

In all three cases, I think the ridership estimates are reasonable. Vancouver especially has a good track record, with Canada Line ridership meeting projections; it’s harder to tell in New York and Boston, which have not opened a rail line recently (New York’s 7 extension was just one stop, and its predicted ridership explicitly depends on future development). Since in general I do think cities should plan their rail extensions around where the busiest buses are, I want to talk about the situations that create a disjunction.

I mentioned in two past posts that rapid transit that surface transit and rapid transit alignments obey different rules, with respect to street geometry. In the more recent post, I used it to argue that tramway corridors should follow buses. In the older post, I argued that subways can take minor detours or go under narrower, slower streets to reach major destinations, for example Century City in Los Angeles, which is near the Wilshire corridor but not on it. However, the latter case isn’t quite what’s happening in any of the three examples here: Second Avenue Subway follows Second Avenue (though phases 1-2 diverge west to serve Times Square, which is important), and the Green Line Extension and Evergreen Line’s routes are both straighter than any bus in the area.

The situation in Boston and Vancouver is not that there’s an arterial bus that misses key destinations. Rather, it’s that the street network is inhospitable to buses. Boston is infamous for its cowpaths: only a few streets, such as Massachusetts Avenue, are wide and long enough to be reasonable corridors for arterial buses, and as a result, the bus network only really works as a subway feeder, with very high rail to bus ridership ratio by US standards. The corridors that do support busier buses – in the Greater Cambridge sector, those are the 77, 71, and 73 buses – are defined by the presence of continuous arterials more than by high latent travel demand.

Vancouver, of course, is nothing like Boston. Its bus grid is Jarrett Walker‘s standard example of an efficient, frequent bus grid. But this is only true in Vancouver proper, and in parts of Burnaby. In the other suburbs, either there’s an arterial street grid but not enough density for a good bus grid (Richmond, Surrey), or there’s no grid at all (Coquitlam). There’s a bus map of the Port Moody-Coquitlam area, with the 97-B line in bright orange and the 5-roundtrips-per-day West Coast Express commuter rail line in purple; the Evergreen Line will run straight from Port Moody to Coquitlam along an alignment parallel to the railroad, whereas the 97-B has to take a detour. Overall, I would class Coquitlam and Somerville together, as places where the street network is so bad for buses that rail extensions can plausibly get a large multiple of the ridership of existing buses.

Second Avenue Subway phase 1 partly belongs in this category, due to the difficulty of going from Second Avenue to Times Square by road, but high projected ridership on phase 3 suggests something else is at play as well. While First and Second Avenues are wide, straight throughfares, functioning as a consistent one-way pair, two factors serve to suppress bus ridership. First, Manhattan traffic is exceedingly slow. The MTA is proud of its select bus service treatments, which boosted speed on the M15 between 125th and Houston Streets to an average of about 10 km/h; in contrast, the Bx12 averages 13-14 km/h west of Pelham Bay Parkway. And second, the Lexington Avenue Line is 360 meters, so riders can walk a few minutes and get on the 6 train, which averages 22 km/h. The Lexington trains are overcrowded, but they’re still preferable to slow buses.

Now, the closeness to the Lexington trains can be waved away for the purposes of the principle of this post: I am interested in where preexisting transit ridership is not a good guide to future transit ridership, and in this example, we see the demand via high ridership on the 4, 5, and 6 trains. However, the issue of slow Manhattan traffic can be folded generally into the issue of circuitous street networks in Boston and Coquitlam.

It makes intuitive sense that the higher the bus-to-rail trip time ratio is, the higher the rail line’s ridership is relative to that of the bus it replaces. But what I’m saying here goes further: the two mechanisms at hand – a street network that lacks continuous arterials in the desired direction, and extensive traffic congestion – reduce the effectiveness of any surface solution. Is it possible to build tramways in the Vancouver suburbs? Yes. But in Coquitlam (and in Richmond and Surrey, for different reasons), they would be circuitous just like the buses. This also limits the ability of bus upgrades to solve transportation problems in such areas.

Now, what of New York? In theory, a bus or tram with absolute signal priority could run down the Manhattan avenues or the major outer-borough throughfares at high speed. But in practice, there is no such thing as absolute signal priority on city streets. It’s possible to speed up surface vehicles via signal priority, but they’ll still have to stop if cross-traffic blocks the intersection. In Paris, the tramways are not fast, averaging around 17-18 km/h, even though they have dedicated lanes and run on wide boulevards in the outer parts of the city and in the inner suburbs; in contrast, Metro Line 14, passing through city center, averages almost 40 km/h.

The implication here is that when a city develops its subway network, it should pay attention not just to where its busiest surface lines are, but also to which areas have intense activity but have suppressed surface ridership because the roads are slow or circuitous. These are often old city centers, built up before there were cars and even before there was heavy horse wagon traffic. Other times, they are general areas where the road network is not geared toward the desired direction of travel.

In cities without subways at all, there is a danger of overrelying on surface traffic, because such cities often have old cores with narrow streets, with intense pressure for auto-oriented urban renewal as they get richer. This is less common in the developed world, but nearly every developed-world city of note either has a rapid transit network already or is completely auto-oriented and has no areas where the road network is weak. Israel supplies several exceptions, since its transportation network is underdeveloped for how rich it is; in past posts I have already voiced my criticism of the decision to center the Tel Aviv Subway around wide roads rather than the older, often denser parts of the city.

In cities with subways, it’s rarely a systemic problem. That is, there’s rarely a specific type of neighborhood that can support higher rapid transit ridership than preexisting transit ridership would indicate. It depends on local factors – for example, in Somerville, the railroads are oriented toward Downtown Boston, but the streets are not, nor are they oriented toward good transfer points to the subway. This means transit planners need to carefully look at the road network for gaps in the web of fast arterials, and consider whether those gaps justify transit investment, as the GLX and Evergreen Line do.

The Northern Branch Extension is a Waste

As I mentioned in yesterday’s post, negotiations in New Jersey between Governor Chris Christie and the state legislature have resulted in a significant increase in the state fuel tax. The money will raise $16 billion for funding the eight-year Transportation Trust Fund plan, and be matched with federal funds to bring the amount up to $32 billion. Unfortunately, the money is being wasted. Details of most of the plan remain vague, but it appears most of the money will go to road repair; for all I know, $4 billion a year is a reasonable amount for this. But one component of the plan is extension of the Hudson-Bergen Light Rail system north into Bergen County, along the Northern Branch. This is at best a marginal project, and in the long run would make regional rail modernization in Northern New Jersey more difficult.

Despite its name, the HBLR only operates in Hudson County. Plans for extension into Bergen County along the Northern Branch still play an outsized political role due to the name of the line, but have not been realized yet. Right now, the line is partly the light rail system of Jersey City, and partly a circumferential line linking dense areas west of the Hudson, as somewhat of a circumferential. As such, it is a combination of a radial and circumferential. The Northern Branch would send it 13 km farther north into suburbia, terminating in Englewood, a town center with a fraction of the job density of the Jersey City CBD. Projected weekday ridership is 21,000, a little more than 1,500 per km, weak for an urban light rail line. (The HBLR’s existing ridership is 54,000 per weekday on 55 km of route.)

The original cost estimate of the Northern Branch extension was $150 million, low for the length of the line. While reactivating a closed commuter rail like the Northern Branch should be cheaper, the line is single-track still hosts some freight service, so light rail would have to build new tracks in the same right-of-way, raising the cost range to that of urban light rail. Unfortunately, the cost rapidly escalated: by 2009 it was up to $800-900 million, and in 2015, after the proposal was shortened to its current length from an 18 km proposal going deeper into the Bergen County suburbs, the cost was up to $1 billion. The cost per rider is still much better than that of the Gateway Tunnel, but it makes the project marginal at best.

While the high cost may be surprising, at least to the reader who is unused to the expense of building in or near New York, the limited ridership is not. The original plan, going beyond Englewood, would have terminated the line in Tenafly, a wealthy suburb where my advisor at Columbia used to live. Many people in Tenafly objected to that plan, not so much on the usual NIMBY grounds of traffic and noise as on the grounds that the line would not be of much use to them. They were interested in taking public transit to go to Manhattan, and the HBLR system would not be of any use. Of course, Columbia professors would not be using a rail network that went directly to Midtown or Lower Manhattan, but most of the suburb’s Manhattan-bound residents work in the CBD and not at Columbia.

I would probably not be this adamantly against the Northern Branch project if it were just one more over-budget light rail line at $45,000 per projected rider. The US has no shortage of these. Rather, it’s the long-term effect on regional rail.

The Northern Branch would make a good commuter rail line, going from Pavonia (or possibly Hoboken) north to Nyack, connecting to the HBLR at its present-day northern terminus, with about the same stop spacing as the proposed HBLR extension. Potentially it could even get a loop similar to the proposed Secaucus loop of the Gateway project allowing it to enter Penn Station directly. An even better connection would involve a second tunnel between Pavonia, Lower Manhattan, and Atlantic Terminal on the LIRR, with a new transfer station at the junction of the Northern Branch and the Northeast Corridor. Consult this map, depicting the inner segments of various potential commuter lines: the Northern Branch is the easternmost yellow line, the Northeast Corridor is in red and green.

The importance of the Northern Branch for regional rail is threefold. First, the easternmost line in North Jersey today, the Pascack Valley Line, misses a large swath of territory farther east, which is covered by the Northern Branch and by the West Shore Line. The West Shore Line actually passes through somewhat denser suburbs, with more Manhattan-bound commuters, but is a major freight route, whereas the Northern Branch has little freight traffic, which can be scheduled around passenger trains or even kicked out. Second, again shared with the West Shore Line, the Northern Branch provides a north-south line in Hudson County west of Bergen Hill, where there is suitable land for transit-oriented development. And third, the terminus, Nyack, is a town center with a walkable core.

I wouldn’t really object to making the Northern Branch light rail if it were cheap. At the original cost estimate of $150 million, I would be mildly annoyed by the lack of long-term thinking, but I’d also recognize that the cost per rider was low, and at worst the state would have to redo a $150 million project. At $1 billion, the calculus changes considerably; it’s a significant fraction of what a tunnel under the Hudson should cost (though not what it does cost given the extreme amount of scope creep).

High costs, as I said in 2011, should not be an excuse to downgrade transit projects to a cheaper, less useful category (such as from a subway to light rail). In this case we see the opposite happen: high costs are a reason to reject a downgraded project, since the cost per rider is no longer low enough to justify shrugging off the long-term effect on regional rail restoration.

Train Weight and Safety

A recent New Jersey Transit train accident, in which one person was killed and more than a hundred was injured, has gotten people thinking about US rail safety again. New Jersey has the second lowest fuel tax in the US, and to avoid raising it, Governor Chris Christie cut the New Jersey Transit budget (see PDF-pp. 4-5 here); perhaps in reaction to the accident, Christie is announcing a long-in-the-making deal that would raise the state’s fuel tax. But while the political system has been discussing funding levels, transit advocates have been talking about regulations. The National Transportation Safety Board is investigating whether positive train control could have prevented the accident, which was caused by overspeed. And on Twitter, people are asking whether Federal Railroad Administration regulations helped protect the train from greater damage, or instead made the problem worse. It’s the last question that I want to address in this post.

FRA regulations mandate that US passenger trains be able to withstand considerable force without deformation, much more so than regulations outside North America. This has made American (and Canadian) passenger trains heavier than their counterparts in the rest of the world. This was a major topic of discussion on this blog in 2011-2: see posts here and here for an explanation of FRA regulations, and tables of comparative train weights here and here. As I discussed back then, FRA regulations do not prevent crumpling of passenger-occupied space better than European (UIC) regulations do in a collision between two trains, except at a narrow range of relative speeds, about 20-25 mph (30-40 km/h); see PDF-pp. 60-63 of a study by Caltrain, as part of its successful application for waivers from the most constraining FRA regulations. To the extent people think FRA regulations have any safety benefits, it is purely a stereotype that regulations are good, and that heavier vehicles are safer in crashes.

All of this is old discussions. I bring this up to talk about the issue of systemwide safety. Jacob Anbinder, accepting the wrong premise that FRA regulations have real safety benefits, suggested on Twitter that rail activists should perhaps accept lower levels of rail safety in order to encourage mode shift from much more dangerous cars toward transit. This is emphatically not what I mean: as I said on Twitter, the same policies and practices that lead to good train safety also lead to other good outcomes, such as punctuality. They may seem like a tradeoff locally within each country or region, but globally the correlation goes the other way.

In 2011, I compiled comparative rail safety statistics for the US (1 dead per 3.4 billion passenger-km), India (1 per 6.6 billion), China (1 per 55 billion), Japan (1 per 51 billion), South Korea (1 per 6.7 billion), and the EU (1 per 13 billion), based on Wikipedia’s lists of train accidents. The number for India is an underestimate, based on general reports of Mumbai rail passenger deaths, and I thought the same was true of China. Certainly after the Wenzhou accident, the rail activists in the developed world that I had been talking to stereotyped China as dangerous, opaque, uninterested in passengers’ welfare. Since then, China has had a multi-year track record without such accidents, at least not on its high-speed rail network. Through the end of 2015, China had 4.3 billion high-speed rail passengers, and by 2015 its ridership grew to be larger than the rest of the world combined. I do not have statistics for high-speed passenger-km, but overall, the average rail trip in China, where there’s almost no commuter rail, is about 500 km long. If this is also true of its high-speed rail network, then it’s had 2.15 trillion high-speed passenger-km, and 1 fatality per 54 billion. This is worse than the Shinkansen and TGV average of zero fatalities, but much better than the German average, which is weighed down by Eschede. (While people stereotype China as shoddy, nobody so stereotypes Germany despite the maintenance problems that led to the Eschede accident.)

I bring up China’s positive record for two reasons. First, because it is an example of how reality does not conform to popular stereotypes. Both within China and in the developed world, people believe China makes defective products, cheap in every sense of the term, and compromises safety; the reality is that, while that is true of China’s general environmental policy, it is not true of its rail network. And second, China does not have buff strength requirements for trains at all; like Japan, it focuses on collision avoidance, rather than on survivability.

The importance of the approaches used in Japan and on China’s high-speed rail network is that it provides safety on a systemwide level. By this I do not mean that it encourages a mode shift away from cars, where fatality rates are measured in 1 per hundreds of millions of passenger-km and not per tens of billions. Rather, I mean that the entire rail network is easier to run safely when the trains are lighter.

It is difficult to find exact formulas for the dependence of maintenance costs on train weight. A discussion on Skyscraper City, sourced to Bombardier, claims track wear grows as the cube of axle load. One experiment on the subject, at low speeds and low-to-moderate axle loads, finds a linear relationship in both axle load and speed. A larger study finds a relationship with exponents of 3-5 in both dynamic axle load and speed. The upshot is that at equal maintenance cost, lighter trains can be run faster, or, at equal speed, lighter trains make it easier to maintain the tracks.

The other issue is reliability. As I explained on Twitter, the same policies that promote greater safety also make the system more reliable, with fewer equipment failures, derailments, and slowdowns. On the LIRR, the heavy diesel locomotives have a mean distance between failures of 20,000-30,000 km, and the medium-weight EMUs 450,000 (see PDF-pp. 21-22 here). The EMUs that run on the LIRR (and on Metro-North), while heavier than they should be because of FRA requirements, are nonetheless pretty good rolling stock. But in Tokyo, one rolling stock manufacturer claims a mean distance between failures of 1.5 million km. While within Japan, the media responds to fatal accidents by questioning whether the railroads prioritize the timetable over safety, the reality is that the overarching focus on reliability that leads to low maintenance costs and high punctuality also provides safety.

In the US, especially outside the EMUs on the LIRR and Metro-North, the situation is the exact opposite. The mean distance between failures for the LIRR’s diesel locomotives is not unusually low: on the MBTA, the average is about 5,000 km, and even on the newest locomotives it’s only about 20,000 (State of the Commuter Rail System, PDF-pp. 8-9). The MBTA commuter rail system interacts with freight trains that hit high platforms if the boxcars’ doors are left open, which can happen if vandals or train hoppers open the doors; as far as I can tell, the oversize freight on the MBTA that prevents easy installation of high platforms systemwide is not actually oversize, but instead veers from the usual loading gauge due to such sloppiness.

Of course, given a fixed state of the infrastructure and the rolling stock, spending more money leads to more safety. This is why Christie’s budget cuts are important to publicize. Within each system, there are real tradeoffs between cost control and safety; to Christie, keeping taxes low is more important than smooth rail operations, and insofar as it is possible to attribute political blame for such low-probability events as fatal train accidents, Christie’s policies may be a contributing factor. My contention here is different: when choosing a regulatory regime and an overarching set of operating practices, any choice that centers high performance and high reliability at the expense of tradition will necessarily be safer. The US rail community has a collective choice between keeping doing what it’s doing and getting the same result, and transitioning operating practices to be closer to the positive results obtained in Japan; on safety, there is no tradeoff.

Mixing Circumferential and Radial Transit in the Other Direction

Two years ago, I wrote a post criticizing subway lines that mix radial and circumferential elements. These lines, for examples Shanghai Metro Lines 3 and 6 and New York’s G train before 2001, contain long radial segments, going from an outlying neighborhood toward city center, but then switch to circumferential mode, avoiding city center and instead serving secondary nodes. Such lines do not get high ridership, because they fail at either radial or circumferential transit. Recently, I was challenged in comments about my support for a mixed line that goes in the other direction: circumferential on the outside, radial on the inside. I would like to talk more about such lines.

Consider the following diagram of a subway system:


The city is shown in light gray, with its center in dark gray. There are five subway lines: the red and blue lines are straightforward radials, the green line is a straightforward circumferential, the yellow line mixes radial and circumferential as criticized in my previous post, the pink line mixes radial and circumferential in the other manner, which I will describe in this post.

The reason the yellow line is going to underperform in this system is that it fails as a radial: it does not go to city center, which has the largest concentration of destinations for transit users. People who have equal access to the red and yellow lines, north and south of city center, are much likelier to choose the red line, which takes them where they want to go. The green line fails as a radial too, but has the positive features of a circumferential: it only serves relatively nearby neighborhoods, which are likely to be denser and produce more riders per unit length; it connects to every line in the system; it allows people to connect between two radial lines without going through the congested city center; it has no dominant direction at the peak, so trains are unlikely to be full in the peak direction and empty in the reverse-peak direction. The yellow line has none of these features, unless one wants to connect between the western legs of the blue and pink lines.

The pink line still works as a radial. Its northeastern leg is a straightforward radial, but even its southwestern leg  works as a radial for people who live west of the yellow line and wish to commute to city center. In this way, it is not truly a mixture of radial and circumferential elements the way the yellow line is, but is simply a radial with a circumferential element tacked on at the end.

Whether the pink line’s circumferential tail works must be evaluated against two alternatives: build nothing, and build a radial leg. This is because in an incrementally-built transit system, the radial parts of the line are typically built first, and the circumferential tail is tacked on as a later extension. In the no-build case, the pink line’s southwestern leg would simply be shorter than the other radial legs in this system. In the radial case, the pink line’s southwestern leg would look symmetric with the northeastern leg. This depends on the following factors:

  1. The strength of the radial alternative. If the radial alternative is strong, then this discourages building the circumferential extension, and vice versa. The radial alternative can be weak in several ways: the southwestern quadrant of the city depicted above may be already replete with radial transit and not need more; the population density in the neighborhoods that would be served by the radial option may be low; and the city’s layout may not be the above-depicted perfect circle, so that there is nowhere for the line to turn except sideways.
  2. The strength of the corridor that would be served by the circumferential leg. The leg can never be a complete circle, so it must be evaluated as a rapid transit line on an individual street or corridor. This far out of city center, transit demand on each route is unlikely to be high, but there may well be exceptions, for example if there is a linear secondary CBD. For example, while Seoul Metro Line 2 is fully circumferential, one of its segments follows a Tehran Avenue, a major street in Gangnam with high transit demand, which would justify a subway even if it weren’t part of a large circle.
  3. The strength of the circumferential transit demand from the end of the potential circumferential extension to the radial segment. In the depicted city, there may be strong demand for east-west transit south of the CBD, and the circumferential pink line is then better at serving it than connecting between the red and yellow lines via the blue line.

The original impetus for this post, as noted at the beginning, is a comment challenging me for my support of an extension of Second Avenue Subway Phase 2, going under 125th Street from the planned terminus at Lexington Avenue to Broadway, with stations at the intersection with each preexisting subway line. I contend that in this case, all three factors above point to a very strong circumferential extension. In order:

  1. The radial alternative is to extend Second Avenue Subway to the north, to the Bronx, presumably under Third Avenue, but according to some railfans also under University Avenue. This is problematic, for three reasons. First, the Bronx already has many north-south lines feeding into Manhattan trunk lines, with mediocre ridership. The Manhattan trunk lines are overloaded, but mostly with traffic coming from the Upper East and West Sides, Harlem, and Washington Heights. Second, Third Avenue is close to the Harlem Line, which could be used for local transit if fares and schedules are integrated with the subways and buses. And third, the plan for Second Avenue Subway is for the line to turn west at 125th toward Lexington, since 125th and Second is not as compelling a destination, and this makes it easier to extend the line to the west than to the north.
  2. 125th Street is a very busy street, and acts as the main street of Harlem. Transit demand is high: four bus routes use the street, with a total of 32,630 boardings per weekday on 125th Street, exclusive of other segments of those routes. This count misses people who board elsewhere and get off on 125th, but conversely assigns people who board on 125th and get off elsewhere to this street and not the other segment. But with this caveat in mind, this points to about 11,000 weekday riders per route-km, ahead of New York’s busiest bus per unit length (the M86, with about 7,000), and not far behind the subway average (15,000). This is despite the fact that, in my experience going between Columbia and the Metro-North station at Park Avenue, those buses are not faster than walking.
  3. East-west transit in Uptown Manhattan consists of Pokey-winning crosstown buses; the 125th Street buses are as slow on 125th. An underrated feature of Second Avenue Subway Phase 1 is that it will soon enable a two-seat subway ride from the Upper East Side to the Upper West Side, West Harlem, and Washington Heights. However, this option will require connecting at Times Square, and is useful mainly for people in the southern areas of the Upper East Side connecting to the 1/2/3 rather than to the A/B/C/D. A two-seat ride based on going up Second Avenue to 125th Street and thence connecting to the 2/3, A/B/C/D, or 1 would enable more connections, many without any backtracking. This could have a potential cascading effect on all Uptown east-west buses, and not just those using 125th Street.

Of course, a Second Avenue Subway extension on 125th Street cannot be exactly like the pink line in the diagram above, because a key feature of it is that the circumferential part is not in fact near the outer end of the city. It’s barely 5 km north of the northern edge of Midtown, not even halfway from Midtown to the northern ends of most preexisting north-south subway lines. This is how it can have such high residential and commercial density and strong transit demand. Much farther north, Fordham Road is a very strong bus corridor, with about 4,500 weekday riders per route-km on the Bx12, but this is at much higher speed than in Manhattan, about 13 km/h rather than 5 km/h. An extension of the A east toward the Bronx under Fordham would underperform, because Fordham just doesn’t have that much demand; but 125th does.

The result of this discrepancy is that in a small city, one whose subway system is only about as large as in the diagram, it’s unlikely that such circumferential extensions would work. A radial line built all the way out is going to have as its terminus either a relatively low-density area or an anchor point, such as a commercial center or big housing project, neither of which lends itself to a strong continuous circumferential corridor. A radial line built part of the way to the edge of the city could potentially find a Tehran Avenue or a 125th Street, but if the system is small, with many key outlying neighborhoods still unserved, then it is usually best to keep extending lines outward.

The factors that conspire to make a 125th Street subway extension work are in place precisely because New York already has a large, mature subway network, in which Second Avenue Subway is a relief line. Certainly the projected demand on Second Avenue is very high, but the East Side is already served by a north-south subway 500-600 meters to the west of this line; it’s being built because this subway is overcrowded, not because the East Side has no access. This means that there’s more leeway with choosing what to do with the line once it reaches Harlem – after all, the Bronx subways are not overcrowded, and do not need relief.

Whereas mixed lines like the above-depicted yellow line are always bad transit, mixed lines like the pink line, in which the circumferential part is farther out than the radial part, are potentially an option for large cities that already have many rapid transit lines. They are especially useful for providing connections between closely parallel radial lines when other crosstown transit options are slow, and should be considered as extensions for relief lines, provided the radial lines farther out do not need relief as well.

What are the Strong Tramway Corridors?

Note on definitions: for the purposes of this post, a tramway is a light rail line that runs predominantly on streets, interfacing with cross-traffic even if it has signal priority. It can be a legacy streetcar in mixed traffic, or a newer light rail line running on dedicated lanes. It is distinguished from lines that have substantial grade-separated segments, including subway-surface lines, where these segments are in city center while the suburban segments are in tramway mode, and tram-trains and most North American light rail lines, where these segments are in the suburbs while the city-center segments are in tramway mode.

Intermediate in capacity between the surface bus and the rapid transit train is the tram. Running on the street, perhaps with signal priority but without the absolute priority that mainline trains have at grade crossings, trams are still surface transit, but feature better ride quality, generally higher capacity in terms of vehicles per hour, and generally bigger vehicles. A number of cities have been building such transit in recent years, most notably Paris, which has been making the rounds on the Transit Center for having almost a million daily riders on its system. The Transit Center gives various recommendations based on Paris’s success, but those recommendations – frequency, fare integration, good transfers – say very little about where a city should be building tramway lines. In this post, I am going to sketch features of good corridors for tramways.

1. Tramways are surface transit

There are various features that make for good surface transit routes. Jarrett Walker, who has extensive experience in bus network redesigns, outlined some of them in a network design document he collaborated on for TransLink. These include high density along the route, relatively balanced demand in both directions, and the potential for a strong everywhere-to-everywhere grid. Additional important features of strong bus routes: a single street with few twists, since turns slow down surface vehicles a lot, and swerving to reach major destinations is often cumbersome; and a wide street, since in practice few cities will give transit dedicated lanes if there’s not enough room for cars as well. These rules do not apply to subways, which can zigzag between different streets or carve a new alignment. However, they do apply to tramways.

2. The strongest bus corridors are in most need of investment

In a city where the buses that can support high frequency already are frequent, the highest potential for extra ridership is on routes that are already strong. Imagine a bus that averages 15 km/h: replacing it with a 20 km/h tram that provides a smoother and more reliable ride has benefits in rough proportion to existing bus ridership. Since both buses and trams are surface transit and follow the same rules, it’s unlikely that there are routes that would make good trams but poor buses. This is in stark contrast with subways, where a potentially strong corridor may not have a continuous surface right-of-way for high bus ridership. On the surface, this corridor could not succeed as either a bus or a tram. This is a specification of the BMT’s all four concept (bus, trolleybus, tramway, subway), in which the four modes work in complement, and the busiest routes in each category are upgraded to the next based on a tradeoff between construction costs and operating costs.

3. In a city with subways, the tramways should be placed on routes that would make poor subway corridors

It goes without saying that tramways should not duplicate subways. But more than that, if a bus route is so strong that it’s a potential subway extension, it should not be turned into a tram. At first pass, this may look like the best bus routes to be turned into trams are not quite the busiest, but the next tier of busier buses. However, this has to do not just with ridership, but also layout relative to the subway system. The subway is almost invariably radial, so strong buses that make easy radials or branches of radials would be strong subway routes, while circumferential buses would not. A radial bus may also turn out to be a poor subway route, if it happens to point in a direction where a subway wouldn’t be a good fit, but this is less likely.

4. A connected network is beneficial, but not required

Ideally, all light rail routes – not just tramways, but also subway-surface routes and tram-trains if they exist – should form a connected graph, with track connections, to enable maximum flexibility in yard placement and reduce the required spare ratio. However, this is not a requirement. Large, busy systems in particular may economically have a yard serving just 1-2 lines, in which case the value of connectedness decreases. In conjunction with point #3, cities with large radial subway networks may have disconnected circumferential tramways, including Paris.

5. When there’s a choice between several tramways and a subway, tramways work better when there’s no dominant route

The construction cost of a subway, in developed countries that are not the US, is $100-300 million per km, with outliers outside the range in both directions. The construction cost of a tramway in the same countries is $15-50 million per km, again, with outliers. The choice of whether to build one subway or six tramways depends on how busy the strongest route is relative to the next five routes. If two strong bus routes are closely parallel, then both should be reckoned together for subway ridership estimates (and to some extent also for tram ridership), since people walk longer to better service, in this case a fast subway rather than a slow bus. Another consideration, more about construction costs than ridership, is whether there exists a good right-of-way for the subway, perhaps an abandoned or low-ridership commuter line that can be converted, that would make it possible to limit tunneling.


Boston has few long, wide roads; Massachusetts Avenue is one of very few exceptions. Downtown Boston and the surrounding neighborhoods have very narrow streets, which is why the Boston bus network is sparse downtown – the buses feed outlying subway stations, or stop at the edge of the central business district at Haymarket, and almost never enter the downtown core. Because of the Green Line, some strong radial routes, such as the Washington Street half of the Silver Line, and the 23 bus on Blue Hill Avenue, are naturally good extensions of the subway-surface network; they’d make good light rail, but not all-surface tramways.

In strongly gridded cities, including Chicago, Vancouver, Toronto, and Los Angeles, it doesn’t make too much sense to build individual tramways; instead, the entire frequent bus grid could be so upgraded, or possibly just the lines that are perpendicular to the rapid transit system in Chicago and Toronto. Unfortunately, this runs into high construction costs, which leads to questions of priorities: build an expansive light rail network, or extend a few subway lines.

I believe Los Angeles and Vancouver are doing right in choosing to prioritize subways on their strongest corridors. Vancouver in particular is an extreme example of point #5 pointing toward a subway, with 80,000 weekday riders on Broadway and another 40,000 on the routes interlining on 4th Avenue 500 meters away (not all on 4th, as two of the four 4th Avenue routes have substantial tails elsewhere), compared with 110,000 on the next five routes combined; Vancouver also seems to have an unusually low subway-to-tram cost ratio, only about 2.7 rather than 6. Los Angeles has a less extreme version of point #5, but Wilshire and very close-by routes dominate east-west traffic, and can also easily feed into the existing subway.

In Chicago, the circumferential nature of the top bus routes – north-south west of the Loop, east-west north and south of it – makes an L extension infeasible, so from point #3, any solution has to involve surface transit. The current plan is dedicated bus lanes. In Toronto this decision is more difficult, and acrid debates between a mostly-surface option and an all-underground option led to the latter choice, influenced by Rob Ford’s unwillingness to take road lanes from cars; right now Toronto is building one subway line (update: it’s mixed subway-surface), under Eglinton, and one tramway, on Finch West.

New York

In New York, Bill de Blasio proposed a tram route near the Brooklyn and Queens waterfront earlier this year; see background articles here and here. This route is ill-suited for the technology proposed, or for any significant investment. The buses along the waterfront are all quite weak. In both Brooklyn and Queens, the busiest buses are in the interior, some going perpendicular to the subway, such as the Q44 on Main Street and B35 on Church, and some serving radial routes that have long been planned to be subway extensions, namely the B46 on Utica and B44 on Nostrand. Select Bus Service investments have targeted these routes, and now the Q44, B44, and most recently the B46 all have SBS features.

Another weakness of the proposed route is that it subtly combines circumferential and radial service; see here for why this is poor practice. While the line is for the most part straight, the north-south segment in Queens is essentially radial, going from Astoria to Long Island City, parallel to the N/Q subways, before switching to circumferential between Long Island City and Downtown Brooklyn. South of Downtown Brooklyn it becomes radial again, connecting to Red Hook and Sunset Park. Riders in Astoria going south are mostly interested in continuing toward Manhattan and not toward Brooklyn; riders in Sunset Park and Red Hook going north would first of all follow different routes (Sunset Park already has the N and R subways and has no use for a detour through Red Hook), and second of all be more interested in going to Manhattan than to Williamsburg and points north.

While de Blasio’s proposal is bad transit, there are routes in New York that could make strong tramways. None of them is on the city’s redevelopment agenda, based on the principle that US cities almost never invest in low- and lower-middle-income neighborhoods except when they are about to gentrify, but the bus ridership there is solid, even though the buses crawl.

The busiest routes in New York are the M15 on 1st and 2nd Avenues in Manhattan, the B46, and the Bx12 on Fordham Road; each has been the single busiest in one of the last few years, but usually the M15 is first. The first two are strong subway routes: the first phase of Second Avenue Subway will soon open, and the rest will be built when the city can find multiple billions per kilometer for them; Utica is also a strong route, and de Blasio proposed it last year before abandoning the idea. But Fordham satisfies point #4 perfectly: it is circumferential, and can only realistically extend the A train, already the system’s longest route, with a mismatch in potential ridership between the core radial segment and what a Fordham subway would get. The Bx12 was the first route to be turned into SBS, and is either the strongest potential tramway in the city, or one of the few strongest.

Going further down the list, we should eliminate the strong Brooklyn routes, except the B41 on Flatbush. The B44 is also a potential subway extension, and the three busiest circumferentials – the B6, B35, and B82 – all parallel the Triboro right-of-way, which by point #5 is a superior project to building multiple light rail lines. The busiest bus in Queens, the Q58, has a long segment between Queens and Brooklyn, about half its total length, that would be obviated by Triboro as well.

The B41 could be a tramway going between City Hall and Kings Plaza, using two dedicated lanes of the Brooklyn Bridge. In that case, the line would effectively act as subway-surface, or more accurately elevated-surface: a surface segment in Brooklyn, a grade-separated segment between Manhattan and Brooklyn. Subway-surface lines should branch, as all current examples do (e.g. Boston Green Line, Muni Metro, Frankfurt U-Bahn), because the subway component has much higher capacity than the surface components. This suggests one or two additional routes in Brooklyn, which do not have strong buses, but may turn into strong tramways because of the fast connection across the river to Manhattan. The first is toward Red Hook, which is not served by the subway and cut off from the rest of the city by the Gowanus Expressway. Unfortunately, there is no really strong corridor for it – the streets are not very wide, and the best for intermediate ridership in Cobble Hill and Carroll Gardens require additional twists to get into the core of Red Hook. Court Street might be the best compromise, but is annoyingly a block away from the F/G trains, almost but not quite meeting for a transfer. The second possible route is along Flushing Avenue toward the Navy Yard; it’s not a strong bus by itself, but the possibility of direct service to Manhattan, if a Flatbush tramway preexists, may justify it.

In the Bronx and Queens, a more conventional network is called for. The Bronx in particular has several strong bus lines forming a good grid, in addition to the Bx12. The east-west routes cannot possibly be made into subway extensions, while the north-south ones have nowhere to go to in Manhattan except possibly a Second Avenue Subway extension, and even that is doubtful (if there’s money to extend Second Avenue Subway north, it should instead go west under 125th Street). A light rail grid could consist of the Bx12 as outlined above, a Tremont line acting as a compromise between the Bx36 and Bx40/42 feeding into Manhattan on 181st Street, a 161st/163rd Street route going into Manhattan on 155th Street replacing the Bx6, a Southern/Manhattan 145th Street route along the Bx19, a Third Avenue route along the Bx15, and a Grand Concourse route along the Bx1/2. Grand Concourse has a subway, but the Bx1/2 nonetheless currently ranks 5th in the city in weekday ridership, and the street is so wide that it’s a good candidate for light rail. Update: a Webster Avenue route along the Bx41 is also feasible, I just forgot it when writing this post.

In Queens, there’s less room for a grid. Main Street is a strong route, connecting to Tremont in the Bronx via the Whitestone Bridge, as the Q44 SBS already does today. A second route between Flushing and Jamaica, on Kissena and Parsons, could also get a tramway. These two routes are uniquely bad subways, since they connect two busy subway lines, both of which could be extended past their termini outward. The main route on Kissena, the Q25, and another route slightly farther east, the Q65, rank 3rd and 2nd among the MTA buses, separate from the New York City Transit buses, with about 20,000 weekday riders each; they also continue north to College Point, which could get a tramway, or perhaps even a subway extension of the 7, depending on whether there are plans to redevelop the Flushing Airport site.

If there is not enough ridership on both Kissena and Main, then only Main should be turned into light rail. More potential corridors include the Q46 on Union Turnpike and the Q10 on Lefferts going to JFK (the busiest MTA bus). Unfortunately, Queens buses tend to be on the long side, e.g. the Q27, the borough’s number 3 bus after the Q58 and Q46, is 15 km long; in the Bronx the longest, Tremont, would be 13 km, cobbled out of busier buses, and most are about 10 km. The Q44 is even longer, at 20 km; light rail is only justified there because of extra local ridership coming from the Q20 local and from the fact that the Queens-Bronx segment over the bridge would be rapid transit. Even then, the tramway may only be justified from Flushing south.

I don’t want to make recommendations for priorities and an exact fantasy map in New York, as those depend on construction costs and the available budget. Fordham and Main Street are most likely the two strongest initial choices. Judging by the cost estimate for de Blasio’s waterfront proposal, tramways in New York are about $60-70 million per km, which in an inverse of the situation in Vancouver leads to an unusually high subway : tram cost ratio, 25 if we take the Manhattan subway extensions (Second Avenue and the 7 extension) as our examples, probably less but not much less if we look at a hypothetical Utica subway. This should bias New York rail extensions toward surface transit.

De Blasio proposed $1.5 billion for about 25 km of tramway on the waterfront. The waterfront idea is bad, and money can and should go elsewhere; 25 km is slightly longer than the combined length of the Bx12 and the B46 from Flushing south. Those two together could be the start of a program to bring surface rail back to New York, using the same routing reasoning that made Paris’s program so successful. Using ridership on the existing buses and adjusting upward for rail bias, initial ridership on those two lines combined should be higher than 100,000 per day, and with more lines and a bigger network, fast multiplication of overall traffic can be expected.

The RPA Continues to Push for the Flawed Crossboro Plan

As the Regional Plan Association continues to work on its Fourth Regional Plan, expected to be published next year, it’s releasing various components of the upcoming agenda. One, an update from the Third Regional Plan from 1996, is a line variously called Triboro or Crossboro. In the third plan, Triboro RX was meant to be a circumferential subway line, taking over existing abandoned and low-traffic freight rail rights-of-way in Brooklyn, Queens, and the South Bronx, terminating at Yankee Stadium via a short tunnel. It was never seriously proposed by any political actor, but was briefly mentioned positively by then-MTA chair Lee Sander in 2008, and negatively mentioned by Christine Quinn, who called for a bus line along a parallel alignment in her mayoral campaign in 2013. In 2014, Penn Design proposed a variant it calls Crossboro, which differs from the original Triboro proposal in two ways: first, the stop spacing is much wider, and second, instead of the short tunnel to Yankee Stadium, it continues northeast along the Northeast Corridor, making four stops in the Bronx as in the proposed Metro-North Penn Station Access plan. Crossboro is an inferior proposal, and unfortunately, the fourth plan’s Triboro proposal downgrades it from the original alignment to Crossboro.

As I explained a year and a half ago, specifically in the context of Crossboro, it is poor planning to run train service that begins as a radial and then becomes as a circumferential instead of continuing into the center. The route of Crossboro, and now also the Triboro plan, involves going from the North Bronx to the south in the direction of Manhattan, but then turning southeast toward Queens and Brooklyn, rather than continuing to Manhattan. Briefly, in a system with radial and circumferential routes (as opposed to a grid), circumferential service is the most effective when it connects to secondary centers, and has easy transfers to every radial. If a line runs as a radial and then switches to circumferential, its ability to connect to other radials is compromised, making it a weaker circumferential; nor could it ever be even a half-decent radial without service to the CBD. Lines with such service pattern, such as Line 3 in Shanghai and the G train in New York until 2001, tend to underperform.

However, the stop spacing deserves to be treated separately. Under both Crossboro and the RPA’s new version of Triboro, there are too few stops for the line to be useful as an urban rail service. I’m going to ignore the connection between Queens and the Bronx, which as a major water crossing can be expected to have a long nonstop segment, and talk first about the Bronx, and then about Queens and Brooklyn.

In the Bronx, there are four stops in 10 km, starting counting from where the bridge toward Queens begins to rise. This may be reasonable for a commuter rail service with local service extending well past city limits (to New Rochelle or even Stamford), but when it terminates within the city, it’s too far for people to be able to walk to it. The proposed stops also miss the Bronx’s most important bus route, the Bx12 on Fordham Road, which in 2015 became the city’s busiest single bus route. A stop on the Pelham Parkway, the continuation of Fordham in the East Bronx, would be a massive travel time improvement over trying to reroute the Bx12 to meet a train station near Coop City, the proposed northern terminus of both Crossboro and the new Triboro. Conversely, it would delay few other passengers, by very little, since there would only be one further stop north. The result of the proposed stopping pattern is then that most people living near the line would not be able to either walk to it or take a frequent bus.

In Queens and Brooklyn, starting from Astoria and going south, the route is 26 km long, and the new Triboro makes 17 stops. The average interstation, 1.5 km, is noticeably above the international subway average, and is especially high for New York, whose stop spacing is near the low end globally. The original version had 29 stops over the same distance, and one more stop between Astoria and the bridge. Unlike in the Bronx, in Brooklyn all streets hosting major radial routes get subway stops. However, long stretches of the route get no stops. The stop spacing is not uniform – from Northern Boulevard to Grand Avenue there’s a stretch with 4 stops in 2.8 km (counting both ends), but from Astoria-Ditmars to Northern Boulevard there’s a 2.5 km nonstop service, skipping Astoria Boulevard and Steinway, passing through a medium-density neighborhood south of the Grand Central Parkway with mediocre subway access. A stop at Astoria Boulevard and Steinway is obligatory, and probably also one between Astoria and Northern, around 49th Street. To the south of Grand Avenue, the proposal calls for a 2.1 km nonstop segment to the M terminus at Metropolitan Avenue, skipping Middle Village, which is cut off from Grand by the Long Island Expressway and from the M by cemeteries. An additional stop in the middle of this segment, at Eliot Avenue, is required.

In Brooklyn, the route runs express next to the L train, splitting the difference between serving Broadway Junction (with a connection to the A/C) and Atlantic Avenue (with a connection to the LIRR): the RPA’s diagram depicts a station at Atlantic Avenue but calls it Broadway Junction. Farther south, it makes a few stops on an arc going southwest toward southern Brooklyn; the stops are all defensible, and the stop spacing could potentially work, but there are still potential missing locations, and some nonstop segments in the 1.7 km area. For example, it goes nonstop between Utica and Nostrand Avenues, a distance of 1.7 km, with a good location for an interpolating station right in the middle, at Albany Avenue. From Nostrand west, it stops at a transfer to every subway line, except the R. In that segment, one more stop could be added, between the F and the D/N; the reason is that the gap between these two lines is 1.8 km, and moreover the right-of-way slices diagonally through the street grid, so that travel time from the middle to either stop is longer along the street network. However, overall, this is not why I dislike the route. Finally, at the western end, the route is especially egregious. The right-of-way is parallel to the N train, but then awkwardly misses 59th Street, where the N veers north and starts going toward Manhattan. The original proposal had a stop several blocks away from 59th, with a long transfer to the R (and N); this one drops it, so there is no R transfer in Brooklyn – trains express from the D/N transfer at New Utrecht to the terminus at Brooklyn Army Terminal, where there is very little development. There are practically no through-riders who would be inconvenienced by adding the extra two N stops in between. In contrast, due to the low frequency of the N (it comes every 10 minutes off-peak), making passengers originating in those stations who wish to ride Triboro transfer would add considerably to their travel time.

A route like Triboro has an inherent problem in deciding what stop spacing to use, because as a circumferential, it is intended to be used on a large variety of origin-destination pairs. For passengers who intend to connect between two outer radial legs more quickly than they could if they transferred in Manhattan, the wider stop spacing, emphasizing subway connections, is better. However, the mixed radial-circumferential nature of the new Triboro makes this a losing proposition: there’s no connection to any subway line in the Bronx except the 6. Moreover, in Brooklyn, there’s no connection in Brooklyn to the R, and if there’s a connection to the A/C, it involves walking several hundred meters from what on the L is a separate subway stop.

In contrast, for passengers whose origins are along the line, narrower stop spacing works better, because they’re unlikely to cluster around the connection points with the radial subway lines. (The line has no compelling destinations, except maybe Jackson Heights and Brooklyn College; in the Bronx, the two most important destinations, the Hub and Yankee Stadium, are respectively close to and on the old Triboro route, but far from the new one.) The aforementioned Astoria/Steinway, Eliot, and Albany, as well as the skipped stations along the L and N routes, all have reasonable numbers of people within walking distance, who have either poor subway access (the first three) or only radial access (the L and N stations).

What’s more, if trains make more stops, the increase in travel time for passengers connecting between two legs is not large compared with the reduced station access time for passengers originating at an intermediate station. The reason is that passengers who connect between two legs are not traveling all the way. The fastest way to get from the West Bronx to southern Brooklyn is to take the D train all the way, or take the 4 to the D; from the 6 train’s shed, the fastest way is to take the 6 and transfer to the N/Q at Canal or the B/D at Broadway/Lafayette. No circumferential service can change that. The benefit of circumferential service is for people who travel short segments: between the Bronx and Queens, or between the 7 or the Queens Boulevard trains and the lines in Brooklyn that aren’t the F. Given high circumferential bus ridership in Brooklyn – two circumferential routes, the B6 and B35, rank 2nd and 4th borough-wide and 4th and 7th citywide, despite averaging maybe 9 km/h – connections between two Brooklyn legs are also likely. For those passengers, making a few more local stops would add very little to travel time. The subway has a total stop penalty of about 45 seconds per station. Of the ten extra stops I list as required – Astoria/Steinway, Eliot, Albany, 59th, four along the L, and two along the N – three (the two on the N and 59th) are basically end stations, and few passengers have any reason to travel over more than five of the rest. In contrast, adding these ten stops would improve the quality of transfers to the R and A/C and provide crucial service to intermediate neighborhoods, especially Middle Village.

Finally, let me make a remark about comparative costs. The original Triboro plan required a short tunnel, between Melrose Metro-North station and Yankee Stadium; the new one does not. However, a single kilometer of new tunnel in the context of a 34 km line is not a major cost driver. The new proposal is actually likely to be more expensive. It is longer because of the segment in the Bronx along the Northeast Corridor, about 40 km in total, and 10 km would be alongside an active rail line. There are plans for increased mainline passenger rail service on the line: Penn Station Access, plus any improvements that may be made to intercity rail. Far from offering opportunities to share costs, such traffic means that any such plan would require four tracks on the entire line and flying junctions to separate trains going to Penn Station from trains going to Brooklyn. Fare collection would be awkward, too – most passengers would transfer to the subway, so subway faregates would be required, but commuter rail has no need for faregates, so sharing stations with Penn Station Access would require some kludge that wouldn’t work well for any mode. Tunneling is expensive in New York, but so is at-grade construction; a kilometer of tunnel in the Bronx is unlikely to cost more than configuring an active rail mainline for a combination of suburban and high-frequency urban service.

The RPA proposes the London Overground as a model, treating the new Triboro as a commuter line offering subway service levels. Everywhere else I’d support this idea. But here, it fails. First, as I explained in a previous post, the routing is an awkward mix of radial and circumferential. But second, the stop spacing only works in the context of a long suburban line feeding city center, and not an urban circumferential line. In the context of an urban line, more stops are needed, to let people walk from more neighborhoods to the train, or take a connecting bus. For the most part, the original Triboro plan, designed around interstations of about 900 meters not counting the water crossing, would work well. Crossboro, and its near-clone the new Triboro, is inferior to it in every respect, and the RPA should jettison it from the Fourth Regional Plan in favor of the old proposal.