France won the World Cup. Once the final ended, people all over Paris went out to the streets to celebrate. At Nation I saw impromptu dancing, drivers waving tricolore flags, and car passengers climbing out of their cars to wave their own flags. But the real celebration was elsewhere, on Champs-Elysees in the central business district. This was well covered in the media; the Guardian cites an estimate of one million people going to Champs-Elysees to celebrate, and ESPN reports riots (which I didn’t witness but can easily believe happened given the general conduct I did see) and 110,000 police and gendarmerie officers.
The sidewalks were crowded and it was difficult to move; there were too few street closures, so pedestrians were confined to narrow zones for the most part. But the crowding was worst at the Metro stations, and RATP should learn from this example and do better next time there are large celebrations, perhaps next Bastille Day.
The problem is cascading closures. In London, where the Underground platforms are narrower and have fewer cross-passageways than the Metro platforms here, closures are routine at Bank because often the passageways get dangerously overcrowded. These closures cascade: once Bank is closed to limit crowding, passengers swarm the adjacent stations, such as Moorgate and London Bridge, which are not built to handle the typical Bank crowds, forcing TfL to close them as well.
France won the game around 7 in the evening Paris time. By 8, some stations on Champs-Elysees were closed, and as I sat on my severely delayed Metro Line 1 train, with passengers banging on the train’s walls and ceiling, I heard that they were closing more, ultimately going express from Palais-Royal to Argentine and skipping all the CBD stations, including Etoile. I got off at Argentine, as did practically the entire train. Not designed to handle the crowds of the entire CBD at once, Argentine’s platform was jammed. I spent maybe ten minutes trying to make my way from where I got off to the front end of the platform, where the only exits were, and failed, and at a few points the mass of passengers was such that I thought a stampede was likely. The only reason nobody fell onto the tracks was the platform edge doors, installed during the automation of Line 1.
Trains kept serving the station, dumping more and more people. The only mechanism preventing more passengers from getting on was that the crowding was so intolerable that some people started getting back onto the trains, including eventually me. I couldn’t even get off at the next stop, Porte Maillot – the platform was fine but the train was too crowded – so I got off in the suburbs, at Les Sablons, and walked back east.
Perhaps RATP did eventually close Argentine. But both RATP and the city made crucial mistakes that evening, which they should fix in the future.
First, they should have made the trains free to improve passenger circulation. Paying at the turnstiles takes time. This is especially bad in Paris, where there are separate gates for entry (which are turnstiles) and exit (which are one-way doors), unlike the two-way turnstiles of New York. Moreover, unlike New York, Paris has no large emergency doors that can be opened. All passengers were going in one direction – out – so RATP should have propped the exit doors open to let passengers out more smoothly.
Free transit for special events is routine in Paris. The trains are free around New Year’s, in order to encourage people to take the train rather than add to car traffic and pollution (and perhaps drunk driving). Bastille Day celebrations and any future victory at the World Cup or Euro Cup should be added to the list of free transit events, not to discourage people from driving but to prevent stampedes.
And second, the city should have closed the surrounding area to non-emergency car traffic. Champs-Elysees was closed, but there wasn’t much place to spill over; the side street I took once I tried leaving had a narrow sidewalk, and police cars were parked in a way to restrict people to a constrained exit path. There is no parallel street that can act as a spillover route, and between the Rond-Point and Etoile there is only one crossing street wider than about 25 meters, Avenue George V on the south side (whereas almost all rail alternatives to the Metro Line 1 are on the north side). With narrow side streets, it’s especially important to dedicate space to pedestrians and emergency vehicles and not to cars. This was as far as I can tell not done, making it hard for people to leave the most crowded areas. In contrast, Etoile itself, with twelve avenues radiating from its circle, was not so crowded, as people had escape routes.
World Cup victories are rare enough that cities understandably don’t design their entire layout based on them. But when they do happen, it’s critical to have a plan, and the same is true of other big celebrations, which often occur annually on national days. If passengers are overwhelming the subway, it’s critical to quickly do whatever the agency can to increase throughput at station passageways as well as on the tracks. And if pedestrians are overwhelming the streets above ground, it’s critical to give them more street space, including for entry and exit.
There are two standard reasons why public transit should limit branching. The first is that it reduces frequency on the branches; this is Jarrett Walker’s reason, and distantly the reason why New York doesn’t interline more than two subway services anywhere except 60th Street Tunnel. The second is that it makes schedules more fragile, first because services have to be scheduled more precisely to alternate among branches, and second because delays on one branch propagate to the others. And yet, rail and bus networks still employ branching, due to benefits including better coverage and focusing frequency where demand is the highest. This is especially common on regional rail, where all services are scheduled and often interact with the mainline network, so the second problem of branching is present no matter what. Metro systems instead have less branching, often because they only serve dense areas so that the main benefits of branching are absent. But what about buses?
I posit that bus branching is more valuable in low-density areas than in high-density areas. If an area only has demand for a bus every 30 minutes, and some farther-out places only have demand for an hourly bus, then it’s fine to branch the route in two. The bus would only be useful with some timed transfers at the inner end – maybe it’s feeding a regional train station with a train every half hour – but the Zurich suburbs have half-hourly clockface schedules with timed bus/rail connections and maintain high mode share for how low their density is.
In the other direction, look at Manhattan specifically. I’ve been looking at its bus network even though I’m only supposed to redesign Brooklyn’s. I’ve mentioned before that my epistemology is that if the presence of factor A makes solution B better, then the absence of factor A should make solution B worse. I noticed that the Brooklyn bus network has very little branching: the only route numbers that branch are the B41 and B38, and the only routes with different numbers that share the majority of their lengths are the B67 and B69 (which reverse-branch). However, Manhattan has extensive branching: the M1/2/3/4 share the Madison and Fifth Avenue one-way pair, and the M101/102/103 share the Third and Lexington one-way pair. Understanding why would be useful even if I only care about Brooklyn: if there is a good reason for Manhattan buses to branch then I should consider adding branching in Brooklyn where appropriate, and even if it’s inappropriate, it’s useful to understand what special circumstances make branching good in Manhattan but not in Brooklyn.
As it is, I don’t believe the branching in Manhattan is useful for Brooklyn. This comes from several reasons, at least one of which implies it’s not really useful for Manhattan either, and by extension for other high-density regions.
You can run a bus that comes every half hour on a schedule, making it possible to interline two hourly routes evenly. With some discipline you can go down to 15 minutes, or possibly even 10: Vancouver runs 12-minute limited buses on 4th Avenue on a clockface schedule with on-board fare collection and shared lanes, but there is signal priority at nearly all intersections and relatively little car traffic since the West Side’s street network is rich in arterial roads and distributes cars across other routes (i.e. Broadway, 12th, and 16th Avenues).
In contrast, it’s not really feasible to run buses on a schedule when they come every 5 minutes. There can be a printed schedule, but buses won’t follow it reliably. Once frequency hits about once every 3 minutes, regular street buses bunch so much that adding more buses doesn’t increase passenger capacity, but even in the 5-10 minute range, schedules are less important than headway management, unless the bus has extensive BRT treatments reducing schedule variance. This means that if a bus comes every 10 minutes and is scheduled on headway management, then branching the route means each branch gets service every 20 minutes scheduled on headway management as well. Few passengers would want to ride such a route. This is the worst region for branching, the 7.5-15 minute range in which branches force passengers to use buses that are both infrequent and irregular.
The highest-frequency routes can branch with less risk. If a 5-minute bus branches in two, then each branch gets 10-minute service, at which point reliable schedules are still desirable but not absolutely necessary. How much service do the Manhattan bus trunks run? In the following scheme, peak means the busiest hour in the morning in the peak direction, and off-peak means the lowest frequency between the morning and afternoon peaks, which is usually around 11 am.
M1: 13 buses per hour peak (8 limited, 5 local), 5 off-peak (all local)
M2: 9 peak, 4 off-peak
M3: 6 peak, 6 off-peak
M4: 12 peak (5 limited, 7 local), 6 off-peak (all local)
M101: 6 peak, 6 off-peak (8 in the busiest off-peak hour, 2-3 pm)
M102: 5 peak, 4 off-peak
M103: 5 peak, 4 off-peak
What we see is that Manhattan branches precisely in the worst frequency range. The buses are frequent enough that it’s not possible to run them on a timetable without either much better segregation from traffic than is feasible (even waving away politics) or massive schedule padding, but they still require passengers in Upper Manhattan to wait 10-15 minutes for their specific branch. One might expect that Bus Time would make it easier on passengers by telling them where the bus is, but no, ridership has actually fallen since apps were introduced (and this fall predates the entry of app-hailed TNCs into the city). It turns out passengers like being able to rely on easily memorable clockface schedules, or else on frequencies so high that they only need to wait 5 minutes, not 15.
The street network
Even one-time visitors to New York notice that the avenues in Manhattan are all one-way. This features prominently in the Manhattan bus network, which employs consistent one-way pairs on First/Second, Third/Lex, Madison/Fifth, and Ninth/Tenth. Moreover, again as every visitor to New York knows, Central Park occupies a large blob of land in the middle, interrupting Sixth and Seventh Avenues.
The upshot is that there are more north-south routes north of 110th Street than south of it. This is roughly the branch point on the three trunks that branch (First/Second only carries the M15). In Harlem, there’s demand for buses on Lenox (i.e. Sixth) and Seventh, both of which are two-way there. There’s also commerce on an interpolating route, Manhattan/St. Nicholas, which is effectively 8.5th Avenue in most of Harlem. Farther west, Ninth/Columbus is no longer a useful through-route north of 110th, but instead Tenth/Amsterdam is two-way, and one of the two buses using the Columbus/Amsterdam one-way pair on the Upper West Side, the M11, indeed goes two-way on Amsterdam north of 110th.
This situation occurs very frequently in cities without gridded street networks. One trunk route will split in two, heading to different former villages that were incorporated into the city as it industrialized and grew. Manhattan is unusual among gridded cities in that its avenues are one-way, forcing buses into one-way pairs south of Harlem that, together with Central Park, ensure there are more useful routes north of 110th than south of it. But among cities without a planned street network this is typical.
As a check, let’s look at the bus networks in two ungridded American cities: Boston and Providence. Do they have a lot of interlining, involving one trunk route splitting in two farther out? Yes, they do!
Here is Providence. Going west of Downcity, there are two major routes to Olneyville, Westminster and Broadway, but beyond Olneyville there are four main streets, so each of the two inner corridors carries two bus routes, and one of these four routes even splits in two farther out. Going north, Charles Street carries four routes, branching off at various locations. Going east there’s a bus tunnel to College Hill carrying many routes, but even outside the tunnel, the one-way pair on Angell and Waterman carries three buses, which split in East Providence. And going south and southwest, Broad Street carries multiple routes, and one of its branches, Elmwood, carries two, splitting farther south.
Here is Boston. Unlike in Providence, buses don’t converge on city center, but on subway stations, so the map is much less clean. However, we see the same pattern of trunk routes splitting into branches. For example, going south of Ruggles, many routes go southeast to Dudley and then south on Warren Street, splitting to various destinations in Dorchester, Mattapan, and Hyde Park on the way. Going southwest of Forest Hills we see many routes use Washington Street, some staying on it and branching in Dedham and some veering west to West Roxbury and branching there. Elsewhere in the system we see the same pattern going north of Maverick and Oak Grove, northeast of Malden, west of Harvard (briefly on Mount Auburn), and northwest of Alewife.
One-seat rides and reverse-branching
I have repeatedly criticized the practice of reverse-branching on subway networks, especially New York, in which two train routes share tracks in an outlying area (such as Queens Boulevard) and then split heading into the center (such as Eighth Avenue on the E versus Sixth Avenue on the F). I did so on the same grounds that any branching is suspect: it reduces frequency on specific routes, and makes the schedule more fragile as delays propagate to more of the network. Moreover, the issue of schedule fragility gets worse if many routes share tracks at some point during their journey, whereas with conventional branching there are only two or three branches per trunk and the trunks form self-contained systems. Finally, reverse-branching lacks the main benefit of conventional branching, as it does not concentrate traffic in the core, where there’s most demand.
These issues are present on bus networks, with two modifications:
- The value of one-seat rides is somewhat higher. Transferring between buses is less nice than transferring between subways: in a Dutch study about location decisions, people’s disutility of out-of-vehicle time on buses was 1.5 times as high as on trains.
- Buses can overtake each other and, even without overtakes, run much closer together than trains. The limiting factor to capacity on buses is schedule fragility and bunching and not stopping distances. This means that reverse-branching is less likely to lead to cascading delays – buses do not have a 2-minute exclusion zone behind them in which no buses may enter.
This means that reverse-branching is more defensible on buses than on trains. However, even then, I don’t think it’s a good idea. At least in Manhattan, reverse-branching consists of avenues in Upper Manhattan that have buses going to both the East Side and the West Side: the M7 (serving the Ninth/Tenth pair) and the M102 both run on Lenox, and the M4 and M104 (running on Broadway to Midtown) both run on Broadway in Morningside Heights. These splits both reduce the frequency available to bus riders and should be eliminated. East-west service should be provided with high-quality bus routes on the main streets, especially 125th (which needs a full subway) but also 116th, 135th, 145th, and 155th.
The snag is that grids don’t work well unless they are complete. The Manhattan grid isn’t complete through Upper Manhattan, because 116th and 135th are discontinuous, without a direct connection from Central Harlem to Morningside Heights and West Harlem. However, the M7 route duplicates the 2 and 3 trains, so it’s not necessary for east-west connectivity. The M4 route doesn’t duplicate the subway, but does duplicate the M101, which runs on 125th Street and Amsterdam (and isn’t a reverse-branch because the M11 terminates shortly after 125th), so it’s not useful by itself.
Should buses branch?
There is one solid reason for buses to branch: if the street network has more major routes closer to the center than in outlying areas, then buses running on the outer arterials should come together close to the core. This is common enough on cities with haphazard street networks. It may also be reinforced if there are weak circumferential streets (Sydney is one such example). In contrast, cities with gridded street plans, even broken grids like those of Brooklyn and Tel Aviv, should have little to no bus branching.
If a bus does branch, it should ideally be extremely frequent on the trunk, so that even the branches have decent headway-based service. I’m not willing to commit to a maximum headway, but Barcelona and Toronto both have at worst 8-minute headways on their bus grids, so if that is indeed the maximum then a bus shouldn’t branch if its off-peak frequency is worse than every 4 minutes and better than every 10-20 (the more reliable the timetable is, the lower the upper limit is, since it’s possible to run on a timetable at higher frequency). In my case of interest, Brooklyn, there is exactly one bus route that comes at least every 4 minutes off-peak: the B46 on Utica runs 16 buses per hour in each direction, counting both local and limited (SBS) routes.
The area in which buses absolutely should not branch – strong interconnected networks of arterials (not necessarily grids – Paris’s network counts too), running buses every 5-15 minutes off-peak – is exactly where most strong bus networks are. It’s rare to have a bus that has extremely high frequency all day, because in most functional city such a bus would be a subway already; as it is, Utica has long been New York’s second priority for subway service, after Second Avenue. So for the most part, the places where buses are the strongest are precisely those where branching is the most deleterious. Low-frequency networks, perhaps connecting to a suburban train station with a timed transfer, should add bus branching to their planning toolkit, but high-frequency urban networks should not.
It’s hard to escape the conversation about the decline of the center-left. Whether it’s about non-populist US Democrats, the Israeli Labor Party, Nordic social democrats, German SPD, or French PS, there’s a pan-first world conversation about the crisis of social democracy. People give any number of reasons for it, some suggesting it can be reversed in some ways, but some more skeptical. Branko Milanovic brings up the change in the nature of work from manufacturing with interchangeable workers within one plant to services with fractionalized workers often working remotely as an economic cause of the decline of unions.
Public transportation is sufficiently close to social democracy that it’s important to ask where it’s going politically, if SPD is slipping to third in the polls, PS is irrelevant, the most exciting Democrats are left-populists, etc. YIMBYism can go anywhere politically, but in practice it’s an anti-populist neoliberal policy, affected by the same trends that hollow out social democracy. Fortunately, both issues have a strong likelihood of surviving the decline of the traditional party system with its bosses vs. workers divisions. My goal is to explain why I believe so, and where support for urbanism and public transit will end up politically in the remainder of the century in developed countries.
Patterns of Democracy
In college I read Patterns of Democracy, a study by comparativist Arend Lijphart classifying the world’s stable democracies (including some third-world ones like India and Botswana) along two dimensions: majoritarian (i.e. two-party) vs. consensus-based (i.e. multiparty), and federal vs. unitary. It’s a book-length overview of the elements that go into each dimension, culminating in some regressions showing that majoritarian democracies are not more politically stable and do not economically overperform multiparty ones.
For the purposes of this post, the interesting part of the book is how it treats the various dimensions of partisan political debate within each country. The most popular analysis is one-dimensional left vs. right, followed by two-dimensional schemes separating economic and liberal vs. authoritarian issues (on the Internet, this is Political Compass). But Lijphart uses a seven-dimensional analysis (pp. 76-78), with each country only having at most three or four active at a time:
- Socioeconomic issues, by far the most common point of controversy within each democracy, including the usual left-right issues like tax rates, health, education, etc.
- Religious vs. secular issues, such as the role of religion in education, abortion rights in the US, or sectarian conflict in multisectarian states like Israel, India, and the Netherlands.
- Cultural-ethnic issues, which in most countries pit majority-group hegemony against multiculturalism, but can also include Belgian language politics or Ashkenazi-Mizrahi tensions in Israel.
- Urban vs. rural issues, such as farm aid.
- Regime support, historically the main cleave between social democratic and communist parties, and today the cleave between extreme right parties like the National Front and AfD (or individuals like Donald Trump) and hard right mainstream parties like Sarkozy and Wauquiez’s Republicans and CSU (or individuals like Ted Cruz and Scott Walker).
- Foreign policy, for examples decolonization in postwar France and Britain and the conflict with the Palestinians in Israel.
- Post-materialist issues, including the environmental issues that underlie the New Left, representing the cleave between social democratic and green parties.
The decline of class-based politics
The crisis of social democracy that Milanovic and others observe is about the decline of class-based politics, pitting workers versus bosses, or the working class versus the middle class. Economic differences between mainstream parties are decreasing, to the point that grand coalitions (as in Germany) or de facto grand coalitions (such as the cordon sanitaire agreement in Sweden excluding the far right) are normalized, joined by an elite consensus that’s for the most part neoliberal. In their stead, the growing issue in salience in Lijphart’s classification is cultural-ethnic, incorporating the sectarian aspects of the religious-secular dimension, including immigration, multiculturalism, and various forms of racism.
However, it’s better to divide socioeconomic issues into issues that are class-based and issues that are not. The most familiar issues across the developed world today pit the rich against the poor: tax rates, health care, education, welfare, unions, labor regulations.
But a large number of issues divide people in different industries, with a fair degree of agreement between labor and capital within each industry. One such issue is the environment, on which oil executives and oil rig workers tend to vote the same way while executives at green tech or low-energy intensity companies and their workers tend to vote the other way. Another issue is free trade, where the battle lines today separate import-competing industries from exporters and industries that rely on a global supply chain (including finance). Historically, the Populist movement in turn-of-the-century America was rooted in farmers’ grievances, demanding free silver, which had little appeal to either the bourgeoisie or the urban working class, which channeled its disaffection into socialism instead. Thus the set of non-class-based economic issues should take over Lijphart’s urban-rural and postmodern dimensions.
Transportation as a politically contentious issue has always had one leg in rich vs. poor politics and one leg outside it. On the one hand, the poor generally use public transit more than the rich, and historically suburbanization in the US as well as the UK was fueled by middle-class flight from the city. On the other hand, the issue intersects with environmentalism and with urban-rural politics. Within cities, the differences often revolve around one’s job descriptions: people who need to drive for a living, such as plumbers and generally people who work outside the CBD, are more hostile to road diets than people who do not, who include both professional downtown workers and downtown service workers.
Non-class-based economic issues are not in any decline. On the contrary, the parties designed around them, including green parties and left-liberal parties (such as D66 or the Danish Social Liberal Party), are for the most part doing fine, taking refugees from declining social democratic parties. In the Schröder cabinet, it was the Greens who pushed for an increase in fuel taxes; support for transit over cars will survive whatever happens to the center-left.
The new class divide
While labor vs. capital is increasingly not a big political cleave in the developed world, other class cleaves are rising to take its place. Non-class-based economic issues pit different industries against one another, and often there’s no consistent pattern to who is on what side, and the same is true on non-economic issues. However, in a large number of cases, there is a consistent pattern, which can be approximated as liberal versus conservative, in the 19th century British sense.
In the case of YIMBYism, the debate over housing is really a fight between two elite classes. The YIMBY side is represented by the professional middle class; the other side is represented by homeowners. Moreover, the professional middle class tends to specifically come from globalized industries, drawing workers from all over, most famously tech in the Bay Area. This class has high labor income and low capital income as well as local social capital, which explains both YIMBYs’ indifference to preserving property values and preference for preemption laws disempowering local notables. Homeowners are the exact opposite: they tend to have high local property values and local social capital relative to their labor income, which means they favor restrictions on housing construction economically and a hyperlocal process in which they’re privileged participants politically.
For the most part, other non-economic issues correlate with the same cleave between the two elites. Middle-class newcomers are overwhelmingly attracted to production amenities of specific global industries (again, Bay Area tech, but also New York and London finance, Paris conglomerates, etc.), which benefit from free trade and have such diverse worker bases that they fall on the liberal side of most debates over immigration. They also tend to cluster in specific job centers, which are at least in principle serviceable by public transportation, leading to high transit ridership relative to income. The urban jobs that are most likely to require driving are local services, which are overwhelmingly owned by people who either were born in the city or immigrated so long ago that they are politically and socially equivalent to natives.
I bring up 19th-century Britain and not the US because Britain had an alignment between free trade, urban over rural interests, and internationalism in the Liberal Party, whereas in the US the Democrats were also the white supremacist party and (outside the Northeast) the agrarian party. But 19th century Europe fits the situation in the first world today between than the 19th century United States, which had free land (courtesy of the Indian Wars) and no real landed gentry apart from the antebellum Southern planter class.
So where are the poor?
If both sides of the debate over zoning and urban housing production are middle-class elites, then where is the working class? The answer is, nowhere. There are working-class organizations on the NIMBY side, such as tenant unions and community groups that try to extract maximum value from developers. There are also poor people on the YIMBY side: in the Houston zoning referendum the poor voted against zoning and the middle class voted for, with poor blacks voting the most strongly against zoning, and at a recent hearing in Brooklyn for a mixed high-rise project most whites spoke against the project and most nonwhites spoke in favor.
To the extent there’s a pattern, organized local groups of poor people and/or minorities are NIMBY and generally unreliable about public transit, but when it goes to ballot there is not much difference between how the poor and middle class vote. Organized local groups of the middle class aren’t any less NIMBY than organized low-income groups, but the middle class more readily dismisses local activists as crackpots and nincompoops. It matters that political activists with more talent and ambition than the typical king of a hill can advance to higher levels of government if they come from favored socioeconomic strata.
The situation with public transit remains profoundly different, because it really does maintain some class-based content. But in general transit cities, even flawed ones like New York, tend to have alignment between working- and middle-class organizations in favor of more investment, and then questions like congestion pricing, bus lanes, bike lanes, and pedestrian plazas cut across class lines and cleave people based on where they work and how they get there. In my Brooklyn bus redesign project, I expect allies to include the bus drivers’ union (the drivers are strong supporters of reforms speeding up buses, since they’d make their work safer and more comfortable) and middle-class reformers and opponents to include working- as well as middle-class drivers (since we’re going to propose stronger bus lane enforcement and street redesigns that prioritize buses). Overall drivers outearn transit riders, but the difference tends to be smaller in cities with even semi-decent public transportation than in places like Los Angeles, where transit is so bad that most riders are people too poor to afford a car.
The result is that it’s very easy on both sides to dismiss the other side as an elite fighting the working class, even in public transit (since a substantial segment of the working class really does drive, even though it’s a smaller segment than in the middle class). In reality, on non-class-based issues it’s hard for the poor to truly be relevant as political actors. In the bus redesign project the union has a voice, but the premise of this post is that the political power of unions is in decline; public transit just happens to be an industry that, owing to its Fordist layout, is unusually friendly to unionization, at least until driverless buses are deployed at scale.
In this context, people should avoid dismissing their opponents as rich. Both sides have vanguards that are mostly middle-class, with some rich people sprinkled around. It’s a fight between two elites, and the YIMBY elite has grounds to portray itself as superior to the NIMBY elite, as it’s defined by skilled professions rather than passive property income, but it’s still a privileged elite and not the poor.
Whither transit and urbanism?
I already see some evidence that support for mass transit and urban growth (which mostly, but not exclusively, means YIMBY) is concentrated in the segments that are underlying where left-liberalism is going. New Left parties, including center-left ones (i.e. D66 and the Danish Social Liberals), are fans of transit. Greens tend to have a small-is-beautiful mentality toward cities, but I believe that this will change soon as green parties become vehicles for more internationalist voters, just as these parties flipped last decade from euroskeptical to europhilic.
What this means is that transit and urbanism as politics are likely to remain important political issues and if anything grow in salience, as they play well to growing cleaves between urban and rural, or between international and local. Whatever happens to specific political parties, these issues will survive.
I’ve mentioned on Twitter that I’m visiting London. I’m taking a lot of railfan trips, one of which was on Tramlink, London’s circumferential light rail service. Tramlink runs in South London, from Wimbledon in the west to Croydon in the east and thence along several branches to southeastern outer neighborhoods. Much of the route uses former mainline rail rights-of-way that were only partly grade-separated. The trains satisfy all of TransitCenter’s principles for good light rail operating practices, but their ridership is lackluster by the standards of Paris, TransitCenter’s comparison city. Tramlink has 30 million annual riders on 28 km of route, or about 3,500 per km per weekday; Ile-de-France’s system had 900,000 daily riders in 2015 on about 100 km route, or 9,000 per km. My goal is to explain why. One reason involves route choice, but the main reason is lack of development; this problem is very common in other cities, and must be added to the other pitfalls that TransitCenter mentions.
The operating practices on Tramlink are not bad. The frequency is high: every 5 minute off-peak. There’s no fare integration with the proper rail network (including the Underground), but the buses in London have no fare integration with the trains either and still have high ridership. The connections with radial train lines are decent, though there’s one big miss (with the Northern line) and one smaller one (with West Croydon, which points to train stations that are served by other lines that do get interchanges); the two most important transfers, Wimbledon and East Croydon, require relatively little walking between platforms. The right-of-way quality is high by light rail standards, mostly in a private right-of-way with only a small extent of street running within Croydon; the average speed is 21 km/h (higher than the Parisian tramways – T3 averages 18 km/h). And yet, ridership is not so strong. London is a big city with high rail ridership, so it’s not a matter of a small city underperforming Paris on raw ridership; something deeper is wrong with Tramlink.
Part of the problem has to involve route layout. East of East Croydon, the route has three branches. Two, heading to Elmers End and Beckenham Junction, keep the route’s circumferential character; in theory it should be faster to take mainline rail and change trains than to ride Tramlink, but in reality the mainline routes that would be used have missed connections and therefore are not useful for diagonal trips. Each of these two branches runs every ten minutes, interlining to a train every five minutes between East Croydon and Wimbledon. However, a third route connects East Croydon and New Addington, a radial line, running every 7.5 minutes. This route does not run through to Wimbledon (which would be a radial-circumferential mix) and exists as an orphaned feeder line, sharing tracks with the two main branches just east of East Croydon (thus, creating schedule conflict due to the uneven frequency on the shared trunk).
But the main difference between Tramlink and the Parisian tramways is adjacent density. London is generally a less dense city than Paris. London has two- and three-story rowhouses with back gardens where Paris has five- to nine-story buildings with high lot coverage. The Tramlink route itself is even less dense, passing through suburbia, industrial sites, and golf courses. The Parisian tramways are all in the suburbs (except for T3), but serve high-density clusters, surrounded by a mixture of mid-rise buildings and social housing towers. This is especially true on the workhorse Parisian routes – T1, T2, and T3, which collectively have about three quarters of the system’s total ridership – but even the other routes, while much weaker than the main three, serve denser areas than Tramlink and get higher ridership per kilometer.
Here is a randomly-selected station on T2, Meudon-sur-Seine:
Compare it with Mitcham, one of the more populated stations on Tramlink between Wimbledon and Croydon:
Also compare both with the site of the missed connection with the Northern line, Morden Road:
I want to make it very clear that the two satellite maps of Mitcham and Morden Road are not representative of all of South London, certainly not when weighting by population. East Croydon is full of mid- and high-rise TOD, and to some extent so is Wimbledon; the two stations rank fifth and sixth in ridership in London excluding the Central London terminals. The problem is that a circumferential line is rarely used over a long stretch. The longer the angle subtended on a circumferential line, the more favorable it is to take the radials and transfer.
London in particular has four-track mainlines on most rail routes, including the London and South Western Main (serving Wimbledon) and the Brighton Main (serving East Croydon), making it easy to run express routes. Every hour, there are 9 trains running nonstop between East Croydon and Clapham Junction, and 16 trains running between Wimbledon and Clapham Junction with two intermediate stops. The diagonal commuter rail trip is faster than Tramlink, even counting transfer time at Clapham Junction.
Paris is full of express trains, represented by the RER. But T3 misses nearly all of the RER connections, which weakens the route but also means that there is no express alternative on the outer margin of Paris; but one would still not take it all the way, especially since there is a forced transfer at Porte de Vincennes. But T1 and T2 have better RER and Transilien connections. The high density all along these routes, and not just at widely-separated key junctions, ensures that there is high demand even on short segments.
In fact, there is circumstantial evidence that T1, T2, and T3 have extensive short-range ridership: their ridership levels per kilometer are very high (respectively 11,000, 12,000, and 15,000 per weekday), and if they had low turnover they would not have capacity for such high ridership. New York has 15,000 weekday subway riders per route-km, and this is with long trains, extensive four-tracking, and higher peak frequency than on the Parisian tramways. It’s hard to imagine comparable ridership levels on a surface tramway without very high turnover, which I have in fact observed riding T3.
In contrast, I saw relatively little turnover between Wimbledon and East Croydon on Tramlink. I saw some, generally involving a small net decrease in passengers on the tram at the first few stations past Wimbledon, but a large proportion of passengers who got on at Wimbledon stayed on until Croydon. To them, the tram is perhaps a slower but cheaper alternative to mainline rail. Some would also ride until one or two stations before East Croydon, within the built-up cluster of Croydon; perhaps their exact destination was closer to one of these tram stations than to East Croydon, where the tram loses a lot of time due to circuitous street running.
Reinforcing the importance of turnover, the tram was crowded. I took it at 4:30 in the afternoon, on the shoulders of rush hour, and it was standing-room only for my entire trip, with considerable crowding among the standees for the first few stations. And yet, despite the crowding, ridership per kilometer is a fraction of that achieved by Paris’s top three tramways, which do not appear more crowded.
I wrote about turnover in the context of Vancouver buses, talking about patterns of development along north-south arterials (Main, Fraser, and Commercial) versus east-west ones (King Edward and 49th). Here we see how it interacts with development on a circumferential tramway within the context of a rapid transit network with fast radial lines. It’s common in a large city to have strong demand for circumferential transit but not so much that full rapid transit is justifiable, leading to tramway networks such as Tramlink and the tramways of Ile-de-France. In this context, it’s important to attract short-hop ridership and not just end-to-end ridership, where the tramway would struggle with the radial rapid transit network. This in turn requires the region to ensure that the intermediate stops generate ample ridership, which requires either uniformly high density (as is the case in and around Paris) or a deliberate effort at TOD in the middle.
This is true for more than just tramways. The fundamental fact about Tramlink and the Ile-de-France tramways is that they are slower than their respective cities’ radial rail networks. The same fundamental fact is true of circumferential buses, even in cities where the radial rail network is light rail rather than rapid transit. In theory this could even happen in an all-bus city, provided the buses’ right-of-way quality were such that the radials were faster than the circumferentials; but in reality this is hard to arrange, since buses get stuck in traffic even when they’re BRT, and there’s more traffic near city center than outside.
When I lived in Vancouver, I was enthusiastic about SkyTrain, which combined high service levels with relatively low construction costs. At the time, the budget for the 12-kilometer Broadway subway from VCC-Clark to UBC was $3 billion (all figures are in Canadian dollars, so subtract 20% for US PPP equivalents). The cost per km was average for a non-English-speaking country, and very low for an English-speaking one, and the corridor has high population and job density. With a ridership projection of 350,000, it was by a large margin North America’s most cost-effective rail extension.
Since then, costs have sharply risen. TransLink lost its referendum and had to scramble for funding, which it got from the new Trudeau administration – but the money was only sufficient to build half the line, between VCC-Clark and Arbutus. With the latest cost overrun, the budget is now $2.83 billion for 5.6 km: C$500 million per kilometer. This is barely below average for a North American subway, and very high for a Continental European one. I tried reaching out to TransLink before the overrun was announced, trying to understand how it was building subways for less money than the rest of North America, but while the agency knew who I am and what I was querying, it didn’t respond; now I know why.
Outside Vancouver, costs are high as well. In Toronto, there are several subway projects recently built or proposed, all expensive.
The least expensive is the Vaughan extension of the Yonge-University-Spadina Line. It opened last year, after a two-year delay, at the cost of $3.2 billion for 8.6 km, or C$370 million per kilometer. Andy Byford, then the chair of the Toronto Transit Commission, now New York City Transit chief, was credited with limiting the cost overruns after problems began. The line is an outward extension into low-density suburbia, and construction has no reason to be difficult. The source also cites the expected ridership: 24 million per year by 2020, or about 80,000 per weekday, for a total of $40,000 per rider, a high though not outrageous figure.
More expensive is the Scarborough subway. Toronto has an above-ground rapid transit line connecting Scarborough with Kennedy on the Bloor-Danforth Line, using the same technology as SkyTrain but with a driver. But unlike Vancouver, Toronto is unhappy with the technology and has wanted to replace the entire line. Originally the plan was to replace it with light rail, but subsequently the plans have changed to a subway. The current plan is to build a 6.4-km nonstop extension of the Bloor-Danforth Line, which would cost $3.35 billion, or C$520 million per kilometer. While this is still slightly below average by American standards, the dominant factor for construction costs in New York is the stations, which means a long subway tunnel with just one new station should be cheap. At the per-item costs of Paris, the line should cost US$1.07 billion, or about C$1.35 billion. At those of Second Avenue Subway, it should cost US$3.3 billion, or about C$4.1 billion. In other words, Toronto is building a subway for almost the same costs as New York, taking station spacing into account, through much lower-density areas than the Upper East Side.
Finally, Toronto has long-term plans for a Downtown Relief Line, providing service to the CBD without using the Yonge-University-Spadina Line. The estimated cost in 2016 dollars is $4-4.4 billion (source, PDF-p. 31), but this assumes faster-than-inflation cost escalation already, and adjusted only for inflation this is higher, about $5-5.5 billion. Per PDF-p. 15 the line would have 6.25-6.7 km of tunnel, for a total cost of about C$800 million per kilometer. The DRL is planned to go under older subways and serve Downtown Toronto, contributing to its higher cost, but the stations are to be constructed cut-and-cover. Despite using cheap construction methods, Toronto is thus about to build an extremely expensive subway.
While I’ve drawn a distinction between costs in English- and non-English-speaking countries, or between common and civil law countries Montreal’s costs are solidly common law Anglophone even though Quebec is Francophone and uses civil law. A 5.8 km extension of the Blue Line is budgeted at $3.9 billion, a total of C$670 million per kilometer. The Blue Line is circumferential, and the extension would extend it further out, but the residential areas served are fairly dense, around 10,000 people per square kilometer on adjacent census tracts.
The last case is Ottawa, where costs are less clear. Ottawa is replacing its BRT line with light rail, which includes a short city center tunnel, called the Confederation Line. The cost is $2.1 billion and the length of the line is 12.5 km, of which 2.5 is in tunnel and the rest is on the surface. The overall project is more expensive, at $3.6 billion, but that includes related works on other lines. I don’t know the portion of the Confederation Line’s cost that’s attributed to the tunnel, so any estimate for tunneling cost has to rely on estimates for the underground premium over surface transit. In Vancouver the original estimate for Broadway rail had a 2.5:1 premium, which would make the cost of the tunnel $320 million per km; however, a more common premium is 6:1, which would raise the cost of the tunnel to $500 million per km.
I don’t know why Canada is so expensive; I’m less familiar with the details of its subway extensions than I am with those of either the US or the UK. The fact that Toronto manages to have very high construction costs even while using cheap methods (cut-and-cover stations, or long nonstop segments) is worrying, since it casts doubt on the ability of high-cost cities to rein in expenses by using cut-and-cover stations rather than mining.
Moreover, the social reasons leading to degradation of civil service in the US are less relevant to Canada. There is less hyperlocal empowerment than in the US and stronger provinces relative to both the federal government and municipalities. Anecdotally I have also found Canadians less geographically solipsistic than Americans. If I had to guess I would say that Canadians look to the US as a best practices model, just as Americans in various cities do to other American (and sometimes Canadian) cities, and if they look at foreign models they look at the UK. Montreal used Paris as a model when it first built its Metro, but more recently its ideas about using France as a model have devolved into no-bid contracts.
I do not know how to code. The most complex actually working code that I have written is 48 lines of Python that implement a train performance calculator that, before coding it, I would just run using a couple of Wolfram Alpha formulas. Here is a zipped version of the program. You can download Python 2.7 and run it there; there may also be online applets, but the one I tried doesn’t work well.
You’ll get a command line interface into which you can type various commands – for example, if you put in 2 + 5 the machine will natively output 7. What my program does is define functions relevant to train performance: accpen(k,a,b,c,m,x1,x2,n) is the acceleration penalty from speed x1 m/s to speed x2 m/s where x1 < x2 (if you try the other way around you’ll get funny results) for a train with a power-to-weight ratio of k kilowatts per ton, an initial acceleration rate of m m/s^2, and constant, linear, and quadratic running resistance terms a, b, and c. To find the deceleration penalty, put in decpen, and to find the total, either put in the two functions and add, or put in slowpen to get the sum. The text of the program gives the values of a, b, and c for the X2000 in Sweden, taken from PDF-p. 64 of a tilting trains thesis I’ve cited many times. A few high-speed trainsets give their own values of these terms; I also give an experimentally measured lower air resistance factor (the quadratic term c) for Shinkansen. Power-to-weight ratios are generally available for trainsets, usually on Wikipedia. Initial acceleration rates are sometimes publicly available but not always. Finally, n is a numerical integration quantity that should be set high, in the high hundreds or thousands at least. You need to either define all the quantities when you run the program, or plug in explicit numbers, e.g. slowpen(20, 0.0059, 0.000118, 0.000022, 1.2, 0, 44.44, 2000).
I’ve used this program to find slow zone penalties for recent high-speed rail calculations, such as the one in this post. I thought it would not be useful for regional trains, since I don’t have any idea what their running resistance values are, but upon further inspection I realized that at speeds below 160 km/h resistance is far too low to be of any consequence. Doubling c from its X2000 value to 0.000044 only changes the acceleration penalty by a fraction of a second up to 160 km/h.
With this in mind, I ran the program with the parameters of the FLIRT, assuming the same running resistance as the X2000. The FLIRT’s power-to-weight ratio is 21.1 in Romandy, and I saw a factsheet in German-speaking Switzerland that’s no longer on Stadler’s website citing slightly lower mass, corresponding to a power-to-weight ratio of 21.7; however, these numbers do not include passengers, and adding a busy but not full complement of passengers adds mass to the train until its power-to-weight ratio shrinks to about 20 or a little less. With an initial acceleration of about 1.2 m/s^2, the program spits out an acceleration penalty of 23 seconds from 0 to 160 km/h (i.e. 44.44 m/s) and a deceleration penalty of 22 seconds. In videos the acceleration penalty appears to be 24 seconds, which difference comes from a slight ramping up of acceleration at 0 km/h rather than instant application of the full rate.
In other words: the program manages to predict regional train performance to a very good approximation. So what about some other trains?
I ran the same calculation on Metro-North’s M-8. Its power-to-weight ratio is 12.2 kW/t (each car is powered at 800 kW and weighs 65.5 t empty), shrinking to 11.3 when adding 75 passengers per car weighing a total of 5 tons. A student paper by Daniel Delgado cites the M-8’s initial acceleration as 2 mph/s, or 0.9 m/s^2. With these parameters, the acceleration penalty is 37.1 seconds and the deceleration penalty is 34.1 seconds; moreover, the paper show how long it takes to ramp up to full acceleration rate, and this adds a few seconds, for a total stop penalty (excluding dwell time) of about 75 seconds, compared with 45 for the FLIRT.
In other words: FRA-compliant EMUs add 30 seconds to each stop penalty compared with top-line European EMUs.
Now, what about other rolling stock? There, it gets more speculative, because I don’t know the initial acceleration rates. I can make some educated guesses based on adhesion factors and semi-reliable measured acceleration data (thanks to Ari Ofsevit). Amtrak’s new Northeast Regional locomotives, the Sprinters, seem to have k = 12.2 with 400 passengers and m = 0.44 or a little less, for a penalty of 52 seconds plus a long acceleration ramp up adding a brutal 18 seconds of acceleration time, or 70 in total (more likely it’s inaccuracies in data measurements – Ari’s source is based on imperfect GPS samples). Were these locomotives to lug heavier coaches than those used on the Regional, such as the bilevels used by the MBTA, the values of both k and m would fall and the penalty would be 61 seconds even before adding in the acceleration ramp. Deceleration is slow as well – in fact Wikipedia says that the Sprinters decelerate at 5 MW and not at their maximum acceleration rate of 6.4 MW, so in the decpen calculation we must reduce k accordingly. The total is somewhere in the 120-150 second range, depending on how one treats the measured acceleration ramp.
In other words: even powerful electric locomotives have very weak acceleration, thanks to poor adhesion. The stop penalty to 160 km/h is about 60 seconds higher than for the M-8 (which is FRA-compliant and much heavier than Amfleet coaches) and 90 seconds higher than for the FLIRT.
Locomotive-hauled trains’ initial acceleration is weak that reducing the power-to-weight ratio to that of an MBTA diesel locomotive (about 5 kW/t) doesn’t even matter all that much. According to my model, the MBTA diesels’ total stop penalty to 160 km/h is 185 seconds excluding any acceleration ramp and assuming initial acceleration is 0.3 m/s^2, so with the ramp it might be 190 seconds. Of note, this model fails to reproduce the lower acceleration rates cited by a study from last decade about DMUs on the Fairmount Line, which claims a 70-second penalty to 100 km/h; such a penalty is far too high, consistent with about 0.2 m/s^2 initial acceleration, which is far too weak based on local/express time differences on the schedule. The actual MBTA trains only run at 130 km/h, but are capable of 160, given long enough interstations – they just don’t do it because there’s little benefit, they accelerate so slowly.
Unsurprisingly, modern rail operations almost never buy locomotives for train services that are expected to stop frequently, and some, including the Japanese and British rail systems, no longer buy electric locomotives at all, using EMUs exclusively due to their superior performance. Clem Tillier made this point last year in the context of Caltrain: in February the Trump administration froze Caltrain’s federal electrification funding as a ploy to attack California HSR, and before it finally relented and released the money a few months later, some activists discussed Plan B, one of which was buying locomotives. Clem was adamant that no, based on his simulations electric locomotives would barely save any time due to their weak acceleration, and EMUs were obligatory. My program confirms his calculations: even starting with very weak and unreliable diesel locomotives, the savings from replacing diesel with electric locomotives are smaller than those from replacing electric locomotives with EMUs, and depending on assumptions on initial acceleration rates might be half as high as the benefits of transitioning from electric locomotives to EMUs (thus, a third as high as those of transitioning straight from diesels to EMUs).
Thus there is no excuse for any regional passenger railroad to procure locomotives of any kind. Service must run with multiple units, ideally electric ones, to maximize initial acceleration as well as the power-to-weight ratio. If the top speed is 160 km/h, then a good EMU has a stop penalty of about 45 seconds, a powerful electric locomotive about 135 seconds, and a diesel locomotive around 190 seconds. With short dwell times coming from level boarding and wide doors, EMUs completely change the equation for local service and infill stops, making more stops justifiable in places where the brutal stop penalty of a locomotive would make them problematic.
Successful transit cities are not alike. There are large differences in how the most expansive transit networks are laid out. It takes multiple series of posts across several blogs (not just mine but also Human Transit and others) covering just one of them, for example stop spacing or how construction contracts are let. With so much variation, it’s easy to get caught up in details that differentiate the best systems. After all, the deepest communities of railfans tend to sprout in the cities with the largest rail networks; arguing with railfans with experience with London, Tokyo, or Paris is difficult because they know intricate details of how their systems work that I am catching up on but only know in the same depth for New York. Add in the fact that London and Paris view each other as peer cities and from there the route to arguing minutiae about two cities that by most standards have good public transit is short.
But what if this is wrong? What if, instead of or in addition to figuring out differences among the top transit cities, it’s useful to also figure out what these transit cities have in common that differentiates them from auto-oriented cities? After all, in other aspects of development or best practices this is well-understood: for example, a developing country can choose to aim to be hyper-capitalist like Singapore or the US or social democratic like Sweden or France, but it had better develop the institutions that those four countries have in common that differentiate them from the third world.
Unfortunately, before discussing what the common institutions to transit cities are, it’s necessary to discuss things that may be common but don’t really matter.
The US as a confounding factor
The biggest problem with figuring out things all good transit cities have in common is that in the developed world, the US (and to some extent Canada and Australia) is unique in having bad transit. Frequent commenter Threestationsquare has a list of cities by annual rapid transit ridership (counting BRT but not infrequent commuter rail, which lowballs parts of the US); New York is near the top, but the second highest in the US, a near-tie between Boston, Chicago, and Washington, would rank #22 in Europe. As a result, some social, political, and technical features that appear to differentiate good and bad transit are not really about transit but about the US and must be discarded as confounding factors. Fortunately, most of these confounding factors are easy to dispose of since they also occur in New York.
The more difficult question concerns factors that are distantly related to the weakness of US transit but are not direct explanations. I wrote about racism as such a factor a few months ago, arguing that high US construction costs come from weak civil service, which in turn comes from the way American segregation works. The US is not uniquely racist or even uniquely segregated; the unique aspect is that it a) has a long-settled oppressed minority and not just immigrants who arrived after the characteristic of the state was established, and b) has segregation within metro areas (unlike Singapore, which has social but not spatial segregation) but not between them (unlike Israel, where the built-up area of Tel Aviv has very few Arabs). But while this can explain why institutions developed in a way that’s hostile to transit, it’s not a direct explanation for poor US transit except in Atlanta, where the white state underinvests in the black city. White people in Boston, Los Angeles, Houston, and other cities with little to no public transit do not avoid the bus or the train out of stereotypes that match typical American racial stereotypes, such as crime; they avoid the train because it doesn’t go where they’re going and the bus because it is slow and unreliable.
There are two ways to avoid confounding factors. The first is the sanity check, where available: if some feature of transit exists across major transit cities but is absent in auto-oriented cities not just in the US but also in Canada, Australia, New Zealand, Israel, and Italy, then it’s likely to be relevant. Unfortunately, clean examples are rare. The second and more difficult method is to have theoretical understanding of what matters.
London and Paris are transit cities. So are Prague and Stockholm. I’ve stressed the importance of scale-variance before: features that work in larger cities may fail in smaller ones and vice versa. Thus, it’s best to look at common features of successful transit cities within each size class separately.
In fact, one way cities can fail is by adopting transit features from cities of the wrong size class. China is making the mistake in one direction: Beijing and Shanghai have no express subway trains or frequent regional rail services acting as express urban rail, and as a result, all urban travel has to slow down to an average speed of about 35 km/h, whereas Tokyo has express regional lines averaging 60 km/h. China’s subway design standards worked well for how big its cities were when those standards were developed from the 1970s to the 1990s, but are too small for the country’s megacities today.
In contrast, in the developed world, the megacities with good public transit all have frequent express trains: Tokyo and Osaka have four-track (or even eight-track!) regional lines, Paris has the RER, New York has express subways (and the premium-price LIRR trains from Jamaica to Penn Station), London has fast regional rail lines and Thameslink and will soon have Crossrail, Seoul has a regional rail network with express trains on Subway Line 1, and Moscow stands alone with a strictly two-track system but has such wide stop spacing that the average speed on the Metro is 41 km/h. Smaller transit cities sometimes have frequent express trains (e.g. Zurich and Stockholm) and sometimes don’t (e.g. Prague), but it’s less important for them because their urban extent is such that a two-track subway line can connect the center with the edge of the built-up area in a reasonable amount of time.
And if China failed by adopting design standards fitting smaller cities than it has today, the US fails in the other direction, by adopting design standards fitting huge megacities, i.e. New York. Small cities cannot hope to have lines with the crowding levels of the Lexington Avenue Line. This has several implications. First, they need to scale their operating costs down, by using proof of payment ticketing and unstaffed stations, which features are common to most European transit cities below London and Paris’s size class. Second, they need to worry about train frequency, since it’s easy to get to the point where the frequency that matches some crowding guideline is so low that it discourages riders. And third, they need to maximize network effects, since there isn’t room for several competing operations, which means ensuring buses and trains work together and do not split the market between them.
The best example of an American city that fails in all three aspects above is Washington. While railfans in Washington lament the lack of express tracks like those of New York, the city’s problems are the exact opposite: it copied aspects of New York that only succeed in a dense megacity. With interlining and reverse-branching, Washington has low frequency on each service, down to 12 minutes off-peak. The stations are staffed and faregated, raising operating costs. And there is no fare integration between Metro and the buses, splitting the market in areas with price-sensitive riders (i.e. poor people) like Anacostia.
The political situation
While I’ve written before about what I think good metro design standards are, these standards themselves cannot separate the major transit cities from cities like Los Angeles (which has about two and a half rail trunks in a metro area larger than that of London or Paris) or Tel Aviv (which has no metro at all). Instead, it’s worth asking why these cities have no large subway systems to begin with.
In the case of Tel Aviv, Israel has had an official policy of population dispersal since independence. After independence the North and South of the country had Arab majorities, and the government wished to encourage Jews to settle there to weaken any Palestinian claims to these areas. As a result, Prime Minister David Ben Gurion rejected a plan to develop an urban rail network centered on Tel Aviv and instead encouraged low-income Jewish immigrants to move far away, either to depopulated Arab towns or to new towns (“development towns”) built at strategic points for national geopolitics. Decentralization was national policy, and with it came auto-oriented urbanism. A less harsh but equally politicized environment led to Malaysia’s auto-centric layout: Paul Barter’s thesis outlines how Malaysia choked informal transit and encouraged auto-oriented suburbanization in order to create an internal market for state-owned automakers.
In the case of the US, the situation is more complex, since there were several distinct political trends in different eras favoring cars. In postwar suburbia (and in Los Angeles going back to the 1920s) it was the association of cars with middle-class normality, and in California also with freedom from hated railroads; it’s related to the fact that American suburbanization was led by the middle class rather than by the working class as with more recent exurbanization. In Israel suburbanization was led by the working class, but the deliberate government policy of decentralization meant that the urban middle class’s demands for better transportation were ignored until the 1990s.
Without enough of an urban middle class to advocate for more transit, US transit withered. New cities in the Sunbelt had little demand for public transit, and in the older cities the middle class cared little for any transit that wasn’t a peak-only commuter train from the suburbs to the CBD. Moreover, in existing transit cities the middle class demanded that the urban layout change to fit its suburban living situation, leading to extensive job sprawl into office parks that are difficult to serve on transit. This paralleled trends in Canada, Australia, and New Zealand; Sydney in particular saw middle-class suburbanization early, like Los Angeles.
The political situation changed in the 1970s, 80s, and 90s, but by then high construction costs, NIMBYism constraining the extent of TOD (unlike in Canada), and indifference to leveraging regional rail for urban transit (as in Canada and until recently Israel but unlike in Australia) made it difficult to build more public transit lines.
Regional rail and TOD
The largest transit cities in the rich and middle-income world all make extensive use of regional rail, with the aforementioned exception of Chinese cities, where the lack of regional rail is creating serious travel pain, and New York, where the city itself is transit-oriented but its suburbs are not. Smaller transit cities usually make use of regional rail as well, but this isn’t universal, and to my understanding is uncommon in Eastern Europe (e.g. Kyiv has one semi-frequent ring line) even in cities with very high metro and tramway usage.
However, smaller transit cities that do not have much regional rail have full metro systems and not just tramways, let alone BRT. Curitiba and Bogota are famous for their BRT-only transit networks, but both instituted their systems in a context with low labor costs and both are building metro systems right now.
The other common element to transit cities is TOD. Here, we must distinguish old cities like London, Paris, Berlin, and Vienna, whose urban layout is TOD because it was laid out decades before mass motorization, and newer cities like Stockholm, Tokyo, and every city in Eastern Europe or the East Asian tiger states. The latter set of cities built housing on top of train stations, often public housing (as in the communist world or in Stockholm) but not always (as in Tokyo and to some extent Hong Kong), in an era when the global symbol of prosperity was still the American car-owning middle class.
The importance of TOD grows if we compare countries with relatively similar histories, namely, the US and Canada. Neither country does much regional rail, both have had extensive middle-class suburbanization (though Canada’s major cities have maintained bigger inner-urban middle classes than the US’s), and English Canada’s cities came into the 1970s with low urban density. The difference is that Canada has engaged in far more TOD. Calgary built up a large CBD for how small the city is, without much parking; Vancouver built up Downtown as well as transit-oriented centers such as Metrotown, New Westminster, Lougheed, and Whalley, all on top of the Expo Line. Nowhere in the US did such TOD happen. Moreover, American examples of partial TOD, including Arlington on top of the Washington Metro and this decade’s fast growth in Seattle, have led to somewhat less awful transit usage than in the rest of the country.
Most cities in the developed world are replete with legacy rail networks that can be leveraged for high-quality public transit. We see cities that aim at transit revival start with regional rail modernization, including Auckland and to some extent Tel Aviv (which is electrifying its rail network and building new commuter lines, but they run in freeway medians due to poor planning). Moreover, we see cities that are interested in transit build up high-rise CBDs in their centers and high- and mid-rise residential development near outlying train stations.
“Regional rail and TOD” is not a perfect formula; it elides a lot of details and a lot of historical factors that are hard to replicate. But both regional rail and TOD have been major elements in the construction of transit cities over the last 60 years, and while they both have exceptions, they don’t have many exceptions. In the other direction, I don’t know of examples of failed TOD – that is, of auto-oriented cities that aggressively built TOD on top of new or existing rail lines but didn’t manage to grow their transit ridership. I do know some examples of failed regional rail, but usually they make glaring mistakes in design standards, especially frequency but also station siting and fare integration.
At a closer in level of zoom, it’s worthwhile to talk about the unique features of each transit city. But when looking at the big picture, it’s better to talk about what all transit cities of a particular size class have in common that auto-oriented cities don’t. Only this way can an auto-oriented city figure out what it absolutely must do if it wants to have better public transit and what are just tools in its kit for achieving that goal.
Boston has two main train stations: South Station, and North Station. Both are terminals, about 2 km apart, each serving its own set of suburbs; as a result, over the last few decades there have been calls to unify the system with a regional rail tunnel connecting the two systems. This tunnel, called the North-South Rail Link, or NSRL, would have been part of the Big Dig if its costs hadn’t run over; as it were, the Big Dig reserved space deep underground for two large bores, in which there is clean dirt with no archeological or geotechnical surprises. The NSRL project had languished due to Massachusetts’ unwillingness to spend the money on it, always understood to be in the billions, but in the last few years the pressure to build it intensified, and the state agreed to fund a small feasibility study.
A presentation of the draft study came out two days ago, and is hogwash. It claims on flimsy pretext that NSRL would cost $17 billion for the tunnel alone. It also makes assumptions on service patterns (such as manual door opening) that are decades out of date not just in Europe and East Asia but also in New York. The Fiscal and Management Control Board, or FMCB, discusses it here; there’s a livestream as well as a link to a presentation of the draft study.
The content of the study is so weak that it has to have been deliberate. The governor does not want it built because of its complexity, no matter how high its benefits. Thus, the state produced a report that sandbags a project it doesn’t want to build. People should be fired over this, starting with planners at the state’s Office of Transportation Planning, which was responsible for the study. The way forward remains full regional rail modernization. As for the cost estimate, an independent study by researchers at Harvard’s Kennedy School of Government estimates it at about $5 billion in today’s money; the new study provides no evidence it would be higher. I urge good transit activists in Massachusetts, Rhode Island, and New Hampshire to demand better of their civil servants.
The study says that the cost of a four-track NSRL tunnel under the Big Dig would be $17 billion in 2028 dollars. In today’s money, this is $12 billion (the study assumes 3.5% annual cost escalation rather than inflation-rate cost escalation). It claims to be based on best practices, listing several comparable tunnels, both proposed and existing:
- California High-Speed Rail tunnels (average estimated cost about $125 million per km, not including overheads and contingency)
- Crossrail (see below on costs)
- The M-30 highway tunnel in Madrid (average cost about $125 million per km of bored tunnel in the mid-2000s, or around $150 million/km in today’s money)
- The canceled I-710 tunnel in California (at 7.2 km and $5.6 billion, $780 million per km
- The Spoortunnel Pannerdensch Kanaal (around $200 million in today’s money for 1.6 km of bore, or $125 million per km)
Unlike the other tunnels on the list, Crossrail has stations frustrating any simple per km cost analysis. The headline cost of Crossrail is £15 billion; however, I received data from a freedom of information request showing that the central (i.e. underground) portion is only £11.6 billion and the rest is surface improvements, and of this cost the big items are £2.2 billion for tunneling, £4.1 billion for stations, £1 billion for tracks and systems, and £2.7 billion for overheads and land acquisition. The tunneling itself is thus around $150 million per km, exclusive of overheads and land (which add 30% to the rest of the project). All of this is consistent with what I’ve found in New York: tunneling is for the most part cheap.
With the exception of Crossrail, the above projects consist of two large-diameter bores. The mainline rail tunnels (California HSR and Pannerdensch Kanaal) are sized to provide plenty of free air around the train in order to improve aerodynamics, a feature that is desirable at high speed but is a luxury in a constrained, low-speed urban rail tunnel. The highway tunnels have two large-diameter bores in order to permit many lanes in each direction. The plan for NSRL has always been two 12-meter bores, allowing four tracks; at the per-km boring cost of the above projects, this 5 kilometer project should cost perhaps a billion dollars for tunneling alone.
The stations are typically the hard part. However, NSRL has always been intended to use large-diameter tunnels, which can incorporate the platforms within the bore, reducing their cost. Frequent commenter Ant6n describes how Barcelona used such a tunnel to build Metro Lines 9 and 10, going underneath the older lines; the cost of the entire project is around $170 million per km, including a cost overrun by a factor of more than 3. Vertical access is likely to be more difficult in Boston under the Big Dig than in Barcelona, but slant shafts for escalators are still possible. At the worst case scenario, Crossrail’s station costs are of an order of magnitude of many hundreds of millions of dollars each, and two especially complex ones on Crossrail 2 are £1.4 billion each; this cost may be reasonable for Central Station at Aquarium, but not at South Station or North Station, where there is room for vertical and slant shafts.
It’s possible that the study made a factor-of-two error, assuming that since the mainline rail comparison projects have two tracks, their infrastructure is sized for two urban rail tracks, where in reality a small increase in tunnel diameter would permit four.
Researchers at the Harvard Kennedy School of Government came up with an estimate of $5.9 billion in 2025 dollars for a four-track, three-station NSRL option, which is about $5 billion today. Their methodology involves looking at comparable tunneling projects around the world, and averaging several averages, one coming from American cost methodology plus 50% contingency, and two coming from looking at real-world cost ranges (one American, one incorporating American as well as rest-of-world tunnels). Their list of comparable projects includes some high-cost ones such as Second Avenue Subway, but also cheaper ones like Citybanan, which goes deep underneath Central Stockholm with mined tunnels under T-Centralen and Odenplan, at $350 million per km in today’s money.
But the MassDOT study disregarded the expertise of the Kennedy School researchers, saying,
Note: The Harvard Study did not include cost for the tunnel boring machine launch pit and only accounted for 2.7 miles of tunneling (the MassDOT studies both accounted for 5 miles of tunneling), and no contingency for risk.
This claim is fraudulent. The Kennedy School study looks at real-world costs (thus, including contingency and launch pit costs) as well as at itemized costs plus 50% contingency. Moreover, the length of the NSRL tunnel, just under 5 km, is the same either way; the MassDOT study seems to be doubling the cost because the project has four tracks, an assumption that is already taken into account in the Kennedy School study. This, again, is consistent with a factor-of-two error.
Moreover, the brazenness of the claim that a study that explicitly includes contingency does not do so suggests that MassDOT deliberately sabotaged NSRL, making it look more expensive than it is, since the top political brass does not want it. Governor Baker said NSRL looks expensive, and Secretary of Transportation Stephanie Pollack is hostile as well; most likely, facing implicit pressure from above, MassDOT’s overburdened Office of Transportation Planning scrubbed the bottom of the barrel to find evidence of absurdly high costs.
Massachusetts really does not want or understand electrification. Even some NSRL supporters believe electrification to be an expensive frill that would sink the entire project and think that dual-mode locomotives are an acceptable way to run trains in a developed country in the 2010s.
In fact, dual-mode locomotives’ weak performance serves to raise tunneling costs. Struggling to accelerate at 0.3 m/s^2 (or 0.03 g), they cannot climb steep grades: both the Kennedy School and MassDOT studies assume maximum 3% grades, whereas electric multiple units, with initial acceleration of 1.2 m/s^2, can easily climb 4% and even steeper grades (in theory even 10%, in practice the highest I know of is 7%, and even 5% is rare), permitting shorter and less constrained tunnels.
As a result of its allergy to electrification, MassDOT is only proposing wiring between North Station and the next station on each of the four North Side lines, a total of 22.5 route-km. This choice of which inner segments to electrify excludes the Fairmount Line, an 8-stop 15 km mostly self-contained line through low-income, asthma-riven city neighborhoods (source, PDF-pp. 182 and 230). Even the electrification the study does agree to, consisting of about 30 km of the above surface lines plus the tunnels themselves, is projected to cost $600 million. Nowhere in the world is electrification so expensive; the only projects I know of that are even half as expensive are a pair of disasters, one coming from a botched automation attempt on the Great Western Main Line and one coming from poor industry practices on Caltrain.
A more reasonable American budget, based on Amtrak electrification costs from the 1990s, would be somewhat less than $2 billion for the entire MBTA excluding the already-wired Providence Line; this is the most familiar electrification scheme to the Bostonian reader or planner. At French or Israeli costs, the entire MBTA commuter rail system could be wired for less than a billion dollars.
Another necessary element is conversion to an all-EMU fleet, to increase performance and reduce operating costs. Railway Gazette reports that a Dutch benchmarking study found that the lifecycle costs of EMUs are half as high as those of diesel multiple units. As the MBTA needs to replace its fleet soon anyway, the incremental cost of electrification of rolling stock is negative, and yet the study tacks in $2.4 billion on top of the $17 billion for tunneling for vehicles.
A miscellany of incompetence
In addition to the sandbagged costs, the study indicates that the people involved in the process do not understand modern railroad operations in several other ways.
First, door opening. While practically everywhere else in the first world doors are automatic and opened with the push of a button, the MBTA insists on manual door opening. The MassDOT study gives no thought to high platforms and automatic doors (indeed, the Old Colony Lines are already entirely high-platform, but some of their rolling stock still employs manual door opening), and assumes manual door opening will persist even through the NSRL tunnels. Each train would need a squad of conductors to unload in Downtown Boston, and the labor costs would frustrate any attempt to run frequently (the study itself suggests hourly off-peak frequency; in Paris, RER lines run every 10-20 minutes off-peak).
Second, capacity. The study says a two-track NSRL would permit 17 trains per hour in each direction at the peak, and a four-track NSRL would permit 21. The MBTA commuter rail network is highly branched, but not more so than the Munich S-Bahn (which runs 30 at the peak on two tracks) and less so than the Zurich S-Bahn (which before the Durchmesserlinie opened ran either 20 or 24 tph through the two-track tunnel, I’m not sure which).
Worse, the FMCB itself is dumbfounded by the proposed peak frequency – in the wrong direction. While FMCB chair Joe Aiello tried explaining how modern regional rail in Tokyo works, other members didn’t get it; one member dared ask whether 17 tph is even possible on positive train control-equipped tracks. My expectations of Americans are low enough that I am not surprised they are unaware that many lines here and in Japan have automatic train protection systems (ETCS here, various flavors of ATC in Japan) that meet American PTC standards and have shorter minimum headways than every 3-4 minutes. But the North River Tunnels run 24-25 peak tph into Manhattan, using ASCES signaling, the PTC system Amtrak uses on the Northeast Corridor; the capacity problems at Penn Station are well-known to even casual observers of American infrastructure politics.
A state in which the FMCB members didn’t really get what their chair was saying about modern operations is going to propose poor operating practices going forward. MassDOT’s study assumes low frequency, and, because there is no line-wide electrification except on the Providence Line and eventually South Coast Rail (where electrification is required for wetland remediation), very low performance. MassDOT’s conception of NSRL has no infill stops, and thus no service to the bulk of the contiguous built-up area of Boston. Without electrification or high platforms, it cannot achieve high enough speeds to beat cars except in rush hour traffic. Limiting the stop penalty is paramount on urban rail, and level boarding, wide doors, and EMU acceleration combine to a stop penalty of about 55 seconds at 100 km/h and 75 seconds at 160 km/h; in contrast, the MBTA’s lumbering diesel locomotives, tugging coaches with narrow car-end doors with several steps, have a stop penalty of about 2.5 minutes at 100 km/h.
The presentation makes it very clear what the value of MassDOT’s NSRL study is: at best none, at worst negative value through muddying the conversation with fraudulent numbers. The Office of Transportation Planning is swamped and could not produce a good study. The actual control was political: Governor Baker and Secretary of Transportation Pollack do not want NSRL, and both the private consultant that produced the study and the staff that oversaw it did what the politicians expected of them.
Heads have to roll if Massachusetts is to plan good public transportation. The most important person good transit activists should fight to remove is the governor; however, he is going to be easily reelected, and replacing the secretary of transportation with someone who does not lie to the public about costs is an uphill fight as well. Replacing incompetent civil servants elsewhere is desirable, but the fish rots from the head.
Activists in Rhode Island may have an easier time, as the state is less hostile to rail, despite the flop of Wickford Junction; they may wish to demand the state take lead on improving service levels on the Providence Line, with an eye toward forcing future NSRL plans to incorporate good regional rail practices. In New Hampshire, provided the state government became less hostile to public investment, activists could likewise demand high-quality commuter rail service, with an eye toward later connecting a North Station-Nashua-Manchester line to the South Side lines.
But no matter what, good transit activists cannot take the study seriously as a planning study. It is a political document, designed to sandbag a rail project that has high costs and even higher benefits that the governor does not wish to manage. Its cost estimates are not only outlandish but brazenly so, and its insistence that the Kennedy School study does not include contingency is so obviously incorrect that it must be considered fraud rather than a mistake. Nothing it says has any merit, not should it be taken seriously. It does not represent the world of transportation planning, but rather the fantasies of a political system that does not understand public transportation.
I wrote a detailed proposal about why New York should deinterline, and how. I got a lot of supportive comments (in the transit blogging sense, i.e. nitpicking), but also some pushback, arguing that people like their one-seat rides, and making them transfer under a more coherent system would make their riding experience worse. I could go on about how London is facing the same problem and is choosing to invest a lot of money into deinterlining in order to increase train capacity, but in the case of New York, there’s a blunter answer: what one-seat ride? The extent of reverse-branching on the subway does not really give people one-seat rides, and New York City Transit is making service decisions that do not maximize one-seat rides even when doing so would be relatively painless.
Most outer branches with just one route naturally offer direct service to the route’s trunk line. Let’s look at the current subway_map, and compare it with my proposed deinterlining, which is again this:
Today, riders on the West End Line only have service on the D, so they only have a one-seat ride to Sixth Avenue. Riders on the Sea Beach Line only have the N, and riders on the local Brighton Line trains only have the Q, so they only have one-seat rides to the Broadway express trains, and if they want to travel to Prince Street or 8th Street-NYU on the R they have to change trains at Canal, which is not a cross-platform transfer. Only a handful of stations get genuine choice between the two trunk lines: 36th Street on the D and N, and the inner few express stops on the B and Q, say up to Newkirk Avenue. These are express stops, with more ridership than the locals, but they’re not the majority of ridership on the subway in Southern Brooklyn. The majority of riders have to deal with the drawbacks of both reverse-branching (slow, infrequent trains) and coherent service (fewer one-seat rides).
Queens Boulevard has the same situation: local and express patterns mix up in a way that makes the choice of one-seat rides much weaker than it appears on the map. Riders at the local stations can choose between the M and the R, two trains that are never more than a few blocks apart in Midtown; only one station on either line is inconvenient to access from the other, 57th Street/7th Avenue, the least busy stop on the Broadway Line in Midtown on a passengers per platform basis (49th and 5th have less ridership but have two platform tracks and no Q service). The express stops get more serious choice, between the E and F, but those are just three stations: Jackson Heights-Roosevelt Avenue, Forest Hills-71st Avenue, and Kew Gardens-Union Turnpike. Queens Plaza has E, M, and R service, but passengers actually getting on at Queens Plaza can equally get on at Queensboro Plaza and ride the N, W, or 7.
Genuine choice between two relatively widely-separated trunk lines on the same trunk only exists in two and a half places in New York: the Central Park West Line offers a choice between the B and C trains, the Nostrand Avenue Line offers a choice between the 2 and 5 trains, and the inner half of the White Plains Line offers a choice between the 2 and 5 trains off-peak (at the peak the 5 runs express, so local stations only get the 2).
New York is blessed with cross-platform interchanges, usually between local and express trains on the same line. Riders on the 1 train are used to transferring to the 2 and 3 trains cross-platform at 96th Street; in the morning, the 1 train’s busiest point is actually from 103th Street to 96th, and not heading into Midtown. With 170,000 boardings at its stations north of 96th per weekday, the 1 is much busier than Nostrand (with 60,000 weekday boardings) or the combined total of local Central Park West stations from 72nd to 116th (with 65,000 boardings). It’s also slightly busier than the White Plains Road Line, let alone the inner segment with both 2 and 5 service (which has 95,000 boardings).
In Queens, a similar situation occurs on the 7. The stations east of Queensboro Plaza, excluding 74th Street-Broadway (where the transfer to the Queens Boulevard Line is), have a total of 215,000 weekday boardings. The trains fill at the outer end and then discharge at 74th Street as most passengers transfer, not cross-platform, to the faster Queens Boulevard Line; then they fill again at the stations to the west and discharge at Queensboro Plaza, which has a cross-platform transfer to the N and W.
This is relevant to some of the few segments of the subway where reverse-branching offers choice between different trunk lines. Passengers on the Nostrand Avenue Line could transfer cross-platform at Franklin Avenue, where the platforms aren’t much narrower than at 96th Street and Broadway, where passenger volumes are almost three times as high. Similarly, passengers on the Central Park West Line and its branches to Washington Heights and Grand Concourse could transfer cross-platform at 125th Street or at Columbus Circle; Columbus Circle is extremely busy already with origin-and-destination traffic, and the interchanges between local and express passengers could not possibly overwhelm it.
Only one place has a difficult connection: 149th Street-Grand Concourse, the interchange between the 2, 4, and 5 trains. This also happens to be the most difficult deinterlining project in general, because of the merger of the 2 and 3 further south; it requires either closing the northernmost two stations on the 3, or opening up a few blocks of Lenox Avenue to construct a pocket track. Because of the disruption involved, this project can be left for last, and come equipped with more passageways at 149th Street, just as London is first deinterlining the Northern line to the south (raising peak capacity on the Bank branch from 26 trains per hour to 32) and leaving the north for later (which would raise capacity further to 36 tph).
NYCT has deinterlined in the past
Upper Manhattan witnessed two deinterlinings in the second half of the 20th century, one in the 1950s and another in the 1990s. The service NYCT inherited from its three predecessor networks had systematic route nomenclature taking into account conventional and reverse branching.
On the IRT, West Side trains were numbered 1 (to Van Cortlandt Park), 2 (to the White Plains Road Line), and 3 (to Harlem-148th Street), and Lexington trains were numbered 4 (to the Jerome Avenue Line), 5 (to the White Plains Road Line), and 6 (to the Pelham Line); 2, 4, and 5 trains ran express, 3 and 6 trains ran local, and 1 trains could be either local or express. In the 1950s, NYCT changed this system on the West Side so that all 1 trains became local and all 3 trains became express. This was the result of track layout: the junction at 96th Street is flat if 3 trains have to cross over to the local tracks and 1 trains have to cross over to the express tracks, but under today’s present service pattern there are no at-grade conflicts. NYCT chose capacity and reliability over offering one-seat rides from West Harlem and Washington Heights to the express tracks.
On the IND, trains were identified by letters. A, C, and E trains ran on Eighth Avenue and B, D, and F trains on Sixth Avenue; A and B trains went to Washington Heights, C and D trains to Grand Concourse, and E and F trains to the Queens Boulevard Line. Local and express trains were identified using letter doubling: a single letter denoted an express train, a doubled one (e.g. AA) a local. The single vs. double letter system ended up discontinued as few trains consistently run express (just the A and D) and several run a combination of local and express (the B, E, F, N, and Q), and NYCT slowly consolidated the trains on Eighth and Sixth Avenue until there were only seven services between them. Eventually the B and C switched northern terminals, so that now the C runs as the local version of the A and the B as something like the local version of the D. Passengers in Washington Heights who wish to use Sixth Avenue Line have to transfer.
The situation on the IND wasn’t as clean as the deinterlining on the IRT. But it shows two important things. First, changes in train service have made the original reverse-branching less tenable from an operational perspective. And second, the value of a one-seat ride from Washington Heights or Central Harlem to local tracks is limited, since everyone takes the express train and transfers at Columbus Circle.
New York is unique among the major subways of the world in the extent of interlining its network has. All routes share tracks with other routes for part of the way, except the 1, 6, 7, and L. The advantage of this system is that it permits more one-seat rides. But the disadvantages are numerous, starting with the fact that delays on one line can propagate to nearly the entire system, and the fragile timetables lead to slower trains and lower capacity. New NYCT chief Andy Byford just released a plan calling for investment in capacity, called Fast Forward, focusing on accessibility and improved signaling, but also mentioning reducing interlining as a possibility to increase throughput.
I covered the interlining issue more generally in my article about reverse branching, but now I want to explain exactly what it means, having learned more about this issue in London as well as about the specifics of how it applies to New York. In short, New York needs to reduce the extent of reverse branching as much as possible to increase train speed and capacity, and can expect serious gains in maximum throughput if it does so. It should ultimately have a subway map looking something like this:
Lessons from London
In London, there is extensive interlining on the Underground, but less so than in New York. The subsurface lines form a complex interconnected system, which also shares tracks with one branch of the Piccadilly line, but the Northern, Central, Victoria, Jubilee, and Waterloo and City lines form closed systems (and the Bakerloo line shares tracks with one Overground line). The Northern line reverse-branches: it has two central trunks, one through Bank and one through Charing Cross; one southern segment, with through-trains to both trunks; and two northern branches, each sending half its trains to each trunk. The other closed systems have just one trunk each, and as a result are easier to schedule and have higher capacity.
As the Underground moves to install the same high-capacity signaling on more and more lines, we can see what the outer limit of throughput is on each system. The Northern line’s new moving-block signaling permits 26 trains per hour on the Bank trunk and 22 on the Charing Cross trunk. When the Battersea extension opens, reverse branching on the south will end, pairing the older line to Morden with Bank and the new extension with Charing Cross, and capacity will rise to 32 tph per trunk. Planned improvements to transfer capacity at Camden Town, the northern branch point, will enable TfL to permanently pair each northern branch with one central trunk, raising capacity to 36 tph per trunk. Moreover, TfL expects moving block signaling to raise District line capacity from 24 tph to 32, keeping the current reverse branching. The Victoria line already runs 36 tph and the Jubilee line soon will too, while the Central line runs 35 tph. So 36 vs. 32 seems like the difference coming from the final elimination of reverse branching, while more extensive reverse branching reduces capacity further.
The reason complex branching reduces capacity is that, as delays propagate, the schedule needs to incorporate a greater margin of error to recover from unexpected incidents. It also slows down the trains, since the trains are frequently held at merge points. The general rule is that anything that increases precision increases capacity (such as automation and moving block signaling) and anything that reduces precision reduces capacity; reverse branching reduces timetable precision, because each train can be delayed by incidents on more than one line, making delays more common.
What deinterlining in New York entails
NYCT has its work cut out for it when it comes to deinterlining. There are eight different points in the system where reverse-branching occurs – that is, where lines that do not share track in Manhattan (or on the G trunk outside Manhattan) share tracks elsewhere.
- The 2 and 5 trains share tracks on the Nostrand Avenue Line.
- The 2 and 5 also share tracks in the Bronx.
- The A and C trains share tracks on the two-track narrows through Lower Manhattan and Downtown Brooklyn.
- The A and D share the express tracks on Central Park West while the B and C share the local tracks.
- The E and F share the express tracks on Queens Boulevard, while the M and R share the local tracks, the E and M share the tunnel from Queens to Manhattan, and the N, R, and W share a different tunnel from Queens to Manhattan.
- The B and Q share tracks in Brooklyn, as do the D and N.
- The F and G share tracks in South Brooklyn.
- The M shares the Williamsburg Bridge tracks with the J/Z but runs in Manhattan on the same tracks as the F.
NYCT should work to eliminate all of the above reverse branches. The easiest to start with is #6: the junction at DeKalb Avenue should be set to keep the B and D trains together and to keep the N and Q together rather than to mix them so that the B shifts to the Q tracks and the D to the N tracks. This requires no changes in physical infrastructure, and has especially high benefits as the junction delays trains by several minutes in each direction. Moreover, the loss of one-seat rides is minimal: the BDFM and NQRW run closely parallel in Manhattan and intersect with a transfer at Herald Square in addition to the inconveniently long BQ/DNR transfer at Atlantic Avenue.
Another relatively easy reverse branch to eliminate is #8, a recent introduction from the 2010 service cuts. Previously, today’s M route in Queens and Manhattan was covered by the V train, which turned on the Lower East Side, while the M ran the same route as the J/Z, merging onto the R and thence the N in Brooklyn at rush hour. Today’s route is thus an M-V merger, which railfans including myself hoped would help decongest the L by creating an alternative route from Williamsburg to Midtown. Unfortunately, such decongestion has not happened, perhaps because gentrification in Williamsburg clusters near the L and not near the J or M.
Fixing the reverse-branching at DeKalb Avenue and on the Williamsburg Bridge is painless. The other reverse branches require a combination of hard decisions and new infrastructure.
Fixing reverse branches #3 and #4 requires no capital investment, just political will. Reverse branch #4 is there because there’s demand for two routes’ worth of capacity in the tunnel from Brooklyn but there’s only one express line on Eighth Avenue, and that in turn is the result of reverse branch #3; thus these two issues should be tackled together.
NYCT should decide between having the A and C trains run express between 145th and 59th Streets and the B and D trains run local, or the other way around. This is not an easy decision: either Washington Heights or Grand Concourse would get consigned to local trains. North of 145th the total number of boardings is 102,000 at B/D stations compared with 79,000 on the A/C, but conversely Concourse riders can change to the express 4 trains whereas Washington Heights’ only alternative is the local 1. However the A and C run, express or local, the E should run the opposite in Manhattan – it can merge to either the local or express tracks – and the express trains should continue to Brooklyn. The map I made doesn’t distinguish local from express service, but my suspicion is that Washington Heights should get express trains, on account of its long commutes and lack of fast alternatives.
The same problem of harshness occurs in reverse-branch #5. In theory, it’s an easy fix: there are three track pairs in Queens (Astoria, Queens Boulevard local, Queens Boulevard express) feeding three tunnels to Manhattan (63rd, 60th, and 53rd Streets). In practice, the three Manhattan trunks have astonishingly poor transfers between them in Midtown. Nonetheless, if it does nothing else, NYCT should remove the R from Queens Boulevard and route all 60th Street Tunnel trains to Astoria; together with fixing DeKalb Avenue, this would separate the lettered lines into two closed systems, inherited from the BMT and IND.
However, undoing the connection between the BMT and the IND probably requires constructing a transfer station in Long Island City between Queensboro Plaza and Queens Plaza, which involves a few hundred meters of underground walkway. Even then, the connection cannot possibly be convenient. The saving grace is that Eighth Avenue, Sixth Avenue, and Broadway are close enough to one another that passengers can walk to most destinations from any line.
Subsequently, NYCT should make a decision about whether to send express Queens Boulevard trains to 63rd Street and Sixth Avenue and local trains to 53rd and Eighth, as depicted in the above map, or the other way around. The problem is that the merge point between 53rd and 63rd Street Tunnels is one station east of Queens Plaza, at a local station, and thus the true transfer point is Roosevelt Avenue, far to the east. Riders on the local stations west of Roosevelt would get no choice where to go (though they get little choice today – both the E and M serve 53rd Street, not 63rd). The argument to do things as I depict them is to give the local stations access to 53rd Street; the argument to switch the lines is that there is more demand on 53rd than 63rd and also more demand on the express tracks than the local tracks, so the busiest lines should be paired. However, this in turn runs into turnback capacity limitations on the E in Manhattan, at the World Trade Center bumper tracks.
Potentially, NYCT could try to convert 36th Street into an express station, so that passengers could connect cross-platform. But such a dig would be costly and disruptive to operations. There were plans to do this at 59th Street on the 1/2/3 a few decades ago, for the transfer to the A/B/C/D, but nothing came of them.
Where new infrastructure is needed
The remaining reverse branches get increasingly more difficult. Already #7 requires new turnouts. The South Brooklyn trunk line has four tracks, but there’s not enough demand (or space in Manhattan) to fill them, so only the local tracks are used. There are occasional railfan calls for express service using the F, but it’s better to instead use the express tracks to segregate the G from the F. The G could be turned at Bergen Street on the local tracks, while the F could use the express tracks and then transition to the locals on new turnouts to be constructed at Carroll Street.
Also in the category of requiring new turnouts is #1: Rogers Avenue Junction is set up in a way that briefly forces the 2, 3, and 5 trains to share a short segment of track, limiting capacity. This can be resolved with new turnouts just east of the junction, pairing Nostrand Avenue Line with the local tracks and the West Side and the portion of the Eastern Parkway Line east of Nostrand with the express tracks and the Lexington Avenue Line. Trains on Eastern Parkway could either all go local, or keep the current mixture of local trains to New Lots (currently the 3) and express trains to Utica (currently the 4), skipping a total of two stations. This fix also reduces passengers’ access to one-seat rides, but at least there is a reasonable cross-platform transfer at Franklin Avenue, unlike on Queens Boulevard or at 145th Street and St. Nicholas.
And then there is #2, by far the most difficult fix. Demand on the White Plains Road branch in the Bronx is too strong to be a mere branch: the combined number of boardings at all stations is 166,000 per weekday, and besides, the line branches to Dyre Avenue near its outer end and thus needs the frequency of either a trunk or two branches to ensure adequate service to each other branch. This is why it gets both the 2 and 5 trains. There is unfortunately no infrastructure supporting a switch eliminating this track sharing: the 4 and 5 trains could both use this line, but then the 2 has no way of connecting to Jerome Avenue Line without new tunnels.
On the map, I propose the most obtrusive method of fixing this problem: cutting the 3 trains to a shuttle, with a new pocket track at 135th Street, letting passengers transfer to the 2, ideally cross-platform. With all through-trains running on the 2, there is no need (or space) for the 5 on White Plains Road, and instead the 5 should help boost the frequency on Jerome Avenue. In addition, some work is required at Woodlawn, which currently has bumper tracks, fine for a single branch but not for a non-branching trunk line (the bumper tracks on the L limit throughput to 26 tph no matter how good the electronics are).
Additional infrastructure suggested by deinterlining
Deinterlining is a service increase. Lines that today only get half or two-thirds service would get full trunk frequency: Second Avenue Subway would get the equivalent of the Q and N trains, the Astoria Line would get the entirety of 60th Street Tunnel’s capacity, Eighth Avenue would get more express trains, and 63rd Street Line and the South Brooklyn Line would get more than just the half-service of the F. With six track pairs on the lettered lines through Midtown and six north and east (Central Park West*2, Second Avenue, Astoria, Queens Boulevard*2), there is no room for natural branching to give more service to busy areas than to less busy ones.
One solution to this situation is targeted development on weak lines. Even with half service, South Brooklyn has underfull F trains, and Southern Brooklyn’s B, D, N, and Q trains aren’t much busier, making this entire area an attractive target for upzoning.
However, it’s more interesting to look at lines with extensions that suggest themselves. Second Avenue Subway has the obvious extension north to Harlem in phase 2, and a potential subsequent extension under 125th Street to Broadway, which is less obvious but popular among most area railfans (including one of my inside sources at NYCT). The Astoria Line has a natural extension to LaGuardia, ideally elevated over Ditmars to capture local ridership on Astoria as well as airport traffic; while the steel el structures in New York are soundboxes, it is possible to build quieter els using concrete (as on the 7 el over Queens Boulevard in Sunnyside) or a mixture of concrete columns and a steel structure (as on the Metro 2 and 6 els here in Paris).
The Nostrand Avenue Line provides an especially interesting example of a subway extension suggested by deinterlining. The terminal, Flatbush Avenue, was intended to be temporary, and as a result has limited turnback capacity. To prevent it from constraining the entire 2 route, which became the city’s most crowded even before Second Avenue Subway began decongesting the 4 and 5, it would be prudent to extend the line to Sheepshead Bay as the city intended when it planned the line in the 1910s.
In contrast, a subway extension under Utica, a stronger bus corridor than Nostrand with a strong outer anchor at Kings Plaza, loses value under deinterlining. It could only get a branch and thus have lower capacity than Nostrand. It would also definitely force branching on the express trains, whereas without such an extension they could run as a single unbranched line between Woodlawn and New Lots Avenue via Jerome Avenue, Lexington Avenue, and Eastern Parkway. A Utica subway should wait until there is political will to fund an entirely new crossing into Manhattan, presumably via Williamsburg to help decongest the L.
A second extension I have occasionally mooted, a subway under Northern, loses value even more. Such a subway would be a fourth trunk line in Queens and have to come at the expense of capacity on Queens Boulevard. It is only supportable if there is an entirely new tunnel to Midtown, passing under the mess that is the tracks in Long Island City.
A deinterlined New York City Subway
Fast Forward proposes moving block signaling on the most crowded subway segments, but typically only on trunks, not branches, and in some cases not even entire trunks. But in the long term, New York should transition to moving blocks and automation on all lines – at the very least the highly automated system used on the L, but ideally fully driverless operation, in recognition that wages are going up with economic growth but driver productivity isn’t. Simultaneously, deinterlined operations should allow tph counts in the mid 30s or even more (Metro 13 here runs 38 tph and Metro 14 runs 42).
Instead of the potpourri of lines offered today, there would be fewer, more intense lines. Nomenclature would presumably change to deal with the elimination of some services, clarifying the nature of the subway as a nine-line system in which five lines have four tracks and four lines have two. Each of these fourteen track pairs should be able to support a train every 90-105 seconds at the peak; not all lines have the demand for such frequency, and some have capacity-limiting bumper tracks that aren’t worth fixing (e.g. the 1 at Van Cortlandt Park), but many lines have the infrastructure and the demand for such capacity, including the express lines entering Midtown from Uptown or Queens.
Off-peak, too, service would improve. There is ample capacity outside rush hour, but turning the system into one of lines arriving every 4-5 minutes with strategic transfers rather than every 8-10 minutes would encourage people to take the trains more often. The trains would simultaneously be faster and more reliable, since incidents on one line would wreck service on other trains on the same line but leave the rest of the network unaffected.
With service improvements both during and outside rush hour, New York could expect to see substantial increases in ridership. Raising peak frequency from the current 24 tph to 36 tph on the busiest lines (today’s 2/3, 4/5, A/D, and E/F) is equivalent to building an entirely new four-track subway trunk line, and can be expected to produce similar benefits for passengers. The passups that have become all too familiar for riders on the 4, L, and other busy trains would become a thing of the past unless ridership rose 50% to match the increase in capacity.