Category: Urban Transit
Linear Compression: How HSR is Like Rapid Transit
A post from last month on Keep Houston Houston notes how high-speed rail transformed Japanese geography to the point that it’s faster to get from Osaka to Nagano via Tokyo than direct despite a doubling of travel distance. The same comment could equally be made about rapid transit within a city: for example, for some origin-destination pairs in Vancouver, it’s faster to go the long way around the Millennium Line than to take a direct bus, and the same principle works in every other city. For both modes of transportation, this comes from high capital costs and high capacity, which make them useful primarily on the thickest travel markets, which tend to be radial around the largest center.
The next step is to look at the effect this change in transportation on economic geography. As I’ve argued before, in both cases the result reinforces preexisting centralization. This is both feedforward and feedback: a dominant city creates enough travel demand to support an HSR network and a dominant CBD creates enough demand to justify digging subways, while at the same time the quickness of travel along the rapid lines makes people emphasize connections along them and deemphasize others.
Concretely, this means that in Manhattan, with its wealth of north-south subway lines and paucity of east-west lines north of Midtown, people identify with the East Side or the West Side. Although the Upper East Side and Upper West Side are socially and demographically similar and are geographically close to each other, the social connections I’ve seen are primarily north-south. A gaming group I participate in many of whose members have recently moved to New York concentrates on the West Side since the earliest members moved to the Upper West Side, and so more people who were living or looking to live in Brooklyn or Queens are moving to Uptown Manhattan in general and the West Side specifically. The subway helps the Greater Upper West Side project influence as far north as Inwood. In contrast, the east-west connection is deemphasized to the point that people I know talk up the cultural differences between the Upper East Side and the Upper West Side, even ones who are not from either neighborhood and are not from the usual high-income demographic (though, of course, the two neighborhoods are culturally dominant and can discuss their own issues via mass media).
I do not know if the above trend is also the case for countries with developed HSR networks. However, another corollary trend is. The importance of the CBD and areas easily accessible from it is that the CBD becomes the more or less neutral choice for where people from different sectors can meet. Midtown can be easily accessed from the Greater Upper West Side, Greater Williamsburg, Greater Bed-Stuy, and so on. This effect then not only reinforces the rapid transit lines but also their nodes, to the point of creating possible centers around accidental transfer stations. In Vancouver, the Commercial Drive area functions as a major meeting location for social groups that are too widely distributed around the metro area for a place in Burnaby or along the Canada Line to be as acceptable. Although the Commercial Drive area hasn’t turned into a CBD and most likely never will, Midtown Manhattan became a CBD largely because of subway lines leading to Uptown Manhattan and Queens. Social meetings and job centers obey similar geographic rules.
In a fractal manner, in each sector there can also be a relatively neutral meeting location when the primary CBD is too expensive or too far, based on either a highway network (for example, White Plains for Westchester) or a rapid transit network (for example, Downtown Brooklyn for all of Brooklyn except Eastern Brooklyn), or even an arbitrary choice of zoning that then becomes self-reinforcing (for example, Metrotown in Burnaby). It promotes a perverse kind of equality, one in which no sector is favored over others, and the social hierarchy is based on the ease of getting to the center, in a similar manner to how in former British colonies with few whites, English sometimes arises as the politically neutral choice of language (or French in former French colonies, etc.), replacing a hierarchy between speakers of different local languages with a hierarchy between people with varying degrees of English fluency.
The exact same node effect can be observed in HSR. Japan’s become more centralized around Tokyo since the Shinkansen was built. In France and Britain there’s heavy centralization, going back many decades; from the start, the lines connecting the capital to the major secondary cities were treated as fast main lines while the others were slower branches. In South Korea, there’s mixed evidence about the role of the KTX in promoting development in secondary cities, but there has been growth in outer exurbs of Seoul that the KTX put within reasonable commute distance, such as Cheonan and Asan, even beyond the general growth of Seoul’s suburbs in the last 30 or so years. It is likely that of the secondary cities, the one emerging the best from this development is Daejeon, both the closest to Seoul and the junction of the lines to Busan/Daegu and Gwangju; for what it’s worth, even before the KTX opened, its metro area had faster population growth than the other major metro areas, excluding satellite metro areas that should really be thought of as suburbs of larger cities.
The meaning of this analogy is that an urban rapid transit network and a national HSR network will look similar. We can now extend the analogy and think in terms of connecting transportation. S-Bahn/RER-style regional rail generally involves routing preexisting commuter lines through new tunnels to provide rapid transit-style urban service; this is analogous to making HSR use legacy lines at lower speed in parts of the system that don’t justify the construction costs of a new line. Branch regional lines and buses feed people into rapid transit stations, in the same manner that legacy rail lines feed people into HSR stations. Some of the alignment questions, such as whether to tunnel or build complex viaducts to reach secondary city centers or to go around them on easier rights of way to save money, are similar, though the answers are often different (i.e. the benefits of the higher-cost alternative are much higher for rapid transit than for HSR since more people ride local transit than intercity transit, while the extra costs are comparable).
It can even explain some of the political coalitions. Rapid transit and HSR are both high-construction cost, high-capacity, long-term investments. They scale up but not down, and therefore cannot be undertaken by a cheeky entrepreneur with a moderate amount of venture capital; they are instead built by governments or very large conglomerates or sometimes both combined, and require careful planning (for example, upzoning) to ensure economic development patterns can reorient along the new infrastructure. They are also signature investments generating a lot of press, to the point that in some cases they can pursued purely for the ribbon cutting, while other forms of rail usually aren’t unless a politician is trying to oversell them as equivalent to rapid transit or HSR but cheaper.
SkyTrain and UBC
I live about 3 minutes from an express bus stop, where I can get the express bus and be at UBC within 15 minutes, whereupon I can walk from the diesel bus loop to my classroom in 6 minutes. Since I teach at 10 in the morning, it means I should leave around 9:30 or just before and then with rush hour headways I can be guaranteed not to be late to my own class. Unfortunately, because classes start on the hour, everyone wants to ride the last bus that makes the 10 am classes, and by the time this bus gets to my neighborhood, it is full. To guarantee getting on a bus I need to be at the bus stop by 9:20 or not much later, which since I have no real reason to show up to campus 15 minutes ahead of time lengthens my effective commute to 40-45 minutes. A bus that is in principle faster door-to-door than any proposed SkyTrain extension, which would serve my area at a much farther away station, becomes more than 10 minutes slower at the time of day relevant to me.
Vancouver has a general problem with passups – that is, passengers at a bus stop who have to let a full bus go. A list of the bus stops with the most passups is dominated by UBC’s peak caused by classes starting and ending at a synchronized time: eight of the top ten stops are for east-west buses serving UBC, and at those stops the passups are concentrated in the AM peak for westbound buses and the PM peak for eastbound ones. Of those eight stops, two, on the 49, are partially connections to the Canada Line (compare passups east and west of Cambie here), but the six on the 99-B are not, since a sizable fraction of riders ride end to end and there are substantial passups west of Cambie as well.
The demand generated by a traditional CBD can be smoothed with flex-time work and with a general spread of the peak around a peak half hour. With a university this is not feasible: to ensure maximum flexibility for students’ class schedule classes should be synchronized. When I was at NUS, a commuter university like UBC, I had a similar problem with full buses heading from campus to the subway stations after classes. Because UBC is nowhere near SkyTrain, its demand has to be spread among many bus routes, and is so great that it’s clogged not just the 99-B but also parallel routes such as the 25 and relief lines such as the 84.
The only alternative for investment in the Broadway corridor that has enough capacity to meet this demand is a full SkyTrain option. Any option that relies on a connecting bus part of the way not only won’t solve the capacity problem, but might even make it worse by concentrating all the UBC-bound demand at the westernmost SkyTrain station on Broadway, at either Granville or Arbutus. Today, people who take the Millennium Line can use the 84, which is faster than the 99-B; any extension of the Millennium Line west, even just to Cambie to complete the gap from Commercial to the Canada Line, is likely to concentrate demand on one corridor, overwhelming the truncated 99-B even further.
A light rail option probably has enough capacity, but does very little for Central Broadway or for completing the SkyTrain gap, and would also require pedestrian-hostile reconfiguration of stoplights and left turn cycles, making crossing the street even harder than it already is. UBC, which doesn’t care about Vancouver’s own needs, advocates an all-light rail option, while the city, which doesn’t care about UBC’s, wants a subway initially going as far west as Arbutus with a bus transfer to the west. A combo option with SkyTrain to Arbutus and light rail the rest of the way exists (Combo A in the alternatives analysis), but is almost as expensive as a full subway. The ridership projection for the combo option is almost even with that of a full subway, but such a projection is based on optimistic assumptions about transfer penalties and passengers’ willingness to travel on slower transit: the combo option is slower by about 7 minutes than the full subway from most preexisting SkyTrain stations as well as from Central Broadway, and requires an extra transfer for people traveling from the Millennium Line or Central Broadway.
Because the project has a $3 billion price tag, various critics have already begun complaining that it’s needlessly expensive (in reality, the inflation-adjusted projected cost per rider is the same as those of the Millennium, Canada, and Evergreen Lines) and proposing inferior solutions, and I believe that this cost is why the city and Translink are thinking of truncating the extension to Arbutus and only doing the rest later. It’s fine to spend a higher sum on the combination of the Canada and Evergreen Lines, which look nice on a map and make a lot of suburban mayors happy, but when it’s just one line that more or less stays within the city it’s too expensive and needs to be chopped into phases.
The other issue is that SkyTrain extensions have been more about shaping than about serving, i.e. serving areas that can be redeveloped rather than ones that are already dense. Look at the density map by census tract here: the residential density on Central Broadway and in the eastern parts of Kits is high, comparable to that of the census tracts hosting most SkyTrain-oriented developments. Even as far west as Alma there’s fairly high residential density. However, this is low-rise density, distributed roughly uniformly in the census tract, rather than clustered in a few high-rise buildings next to the SkyTrain stations. High-rises are possible throughout the corridor – there already are a few near the future Alma and Sasamat stops – but because of Point Grey’s affluent demographic it’s easy to write it off as not densifiable. Empty or very low-density plots are easier to redo from scratch than an existing neighborhood, even if the neighborhood already has enough development to justify a subway.
I suspect part of the problem comes from the context in which Vancouver’s TOD is located in. The Expo Line follows a private right-of-way with pedestrian-hostile streets connecting to stations, and the Millennium Line is elevated over the mostly sidewalk-free Lougheed Highway. The fastest way to get from some houses that are close to SkyTrain on a map to the station is to walk through mall parking lots. The walking range of SkyTrain stations located in unwalkable parts of Burnaby is not as high as it would be at ones located in a walkable urban context. At the level of how many people would live within a kilometer of SkyTrain, Kits and Central Broadway are already outperforming most of the Expo Line’s TOD, and even at the 500-meter range they do quite well; but in Burnaby the relevant distance is much shorter, and this may affect Translink’s ridership projections elsewhere in the metro area.
The only medium- and long-term solution is to find the $3 billion for the UBC extension, just as the metro region will have spent $3.5 billion in 10 years on the Canada and Evergreen Lines. Nothing else works for both UBC and Central Broadway; the counterarguments are based on generalizing from a different urban context; the difference-splitting intermediate solutions make some of the transit problems even worse than they are. It is always wrong to downgrade projects just because of a sticker shock, and if a very large project still has a good cost-benefit ratio then it’s a good investment to raise taxes or borrow money to fund it.
C-Shaped Lines
The ideal rapid transit line looks something like a straight line. It can have deviations, but on a map it will be more or less a line with a definitive direction. Most rapid transit lines are indeed linear, or failing that circular (to provide circumferential service) or L-shaped. In most cities there are just a handful of C-shaped exceptions: London has just one (the Piccadilly Line), Tokyo two (the Marunouchi Line and the Yokosuka-Sobu Line), Paris one (the RER C; Metro 2 and 6 should really count as a circle), Seoul one (Line 6). In contrast, in some cities, such as New York, there are many C-shaped lines. Since most people aren’t traveling in semicircles, it’s worth talking about reasons why cities may build lines that don’t have the most efficient shape.
Reason 1: water
Cities right next to a large body of water may have lines that double back. Chicago has the Blue Line, Toronto has the Yonge-University-Spadina Line, San Francisco has the Daly City-Dublin and Daly City-Fremont BART routes and the T-Third Muni route. If Boston extends the Green Line to Somerville, the Green Line will form a C. Tokyo’s Yokosuka-Sobu through-line is in this category as well. Usually, the transit operator doesn’t expect anyone to take the line for its full length; Toronto is planning a crosstown line bridging the far ends of the C. Such lines are C-shaped because they are really two interlined lines coming from the same direction.
Reason 2: two separate lines joined at the outer end for operational reasons
This can be similar to reason 1 in that nobody is expected to take the line along its full length, but here the joining occurs at the outer end. Singapore’s North-South Line and Vancouver’s Millennium Lines are both examples of this. In Singapore’s case this comes from an international boundary; in Vancouver’s it comes from the need to connect the line to the Expo Line so that trains can go to the maintenance yard, and it proved too hard to connect the lines at the inner end, at Broadway/Commercial. In both examples, what should really be two separate lines are joined by an outer loop that functions as somewhat of a circumferential, but the lines were not planned to provide circumferential service and are not good at connecting to anything other than the two joined lines. (Singapore built a separate circumferential, the Circle Line.) Arguably, the RER C falls into this category too, except the connection between the lines is too inner.
Reason 3: a half-formed circumferential
Hong Kong’s Kwun Tung Line is circumferential in the sense that it doesn’t serve Hong Kong Island, just Kowloon; partially because of water, it is C-shaped. New York’s G route used to be in this category back when it ran to Forest Hills, but in 2001 it was truncated to Court Square and became linear. Other lines in this category are hypothetical: if Paris’s Metro 2 and 6 count as C-shaped, then they fall into this category; Boston’s busiest bus, Line 66, is vaguely C-shaped, acting as a circumferential in the southwestern arc from Harvard to Dudley; and if New York builds Triboro RX then it will fall into this category, too. In this case, usually another reason, or a pure ridership concern, is what prevents completing the line as a full circle, but the line is configured to be useful for interchanges. The Kwun Tung Line is useful for end-to-end trips, but the other hypothetical cases aren’t: Triboro RX would be useful for short trips, but to get from the Bronx to southern Brooklyn, the D is much faster.
Reason 4: administrative boundaries
In regions without much intergovernmental cooperation, administrative boundaries can be as sharp as coastlines. Everything proceeds as in reason #1, but this time the inefficiency is entirely preventable. This specifically affects New York and SEPTA Regional Rail. Morally, New York’s north-south lines should connect the Bronx with Brooklyn and the east-west lines should connect Queens with New Jersey. But because New Jersey is administratively separate, the Queens lines loop back into Brooklyn, creating some awkward shapes on the F, the R, and especially the M both before and after its recent combination with the V. (Some Bronx-Brooklyn lines are also awkwardly shaped, but this is because of water). Likewise, SEPTA Regional Rail barely goes into New Jersey, and only in Trenton; PATCO, serving Camden, is separate, and as a result, while the system had the R# designations, the R5 and R6 were C-shaped and the R7 and R8 self-intersected, helping ensure there was not much suburb-to-suburb ridership.
Reason 5: aberrations
In some cases, such as the Marunouchi Line or Singapore’s self-intersecting Downtown Line, there’s no apparent reason, and in that case the two branches combine to form a C-shaped line for essentially random reasons. Maybe the ideal route through city center is one that connects two branches in the same direction; maybe there is more demand to one direction than to the other.
Of the above five reasons, it is reason 4 that is the most angering. Jersey City and the hill cities to its north have as long a history of ferry-oriented New York suburbanization as Brooklyn. But because of administrative reasons, they never got as much rapid transit, stunting their development. New York’s subway plans never really made any use of the Hudson Tubes, and even the unrealized plans for a North Jersey subway network made surprisingly little use of existing infrastructure. The result: 12 km out of Manhattan, at the same distance as Flushing, New Jersey only has Bogota, Rutherford, and Hackensack; 20 km out, at the same distance as still fairly dense Cambria Heights, New Jersey has Paramus and Montclair.
It’s of course too late for New York to do things right, but for a city just beginning to build a subway network, it’s important to make sure that lines are straight and hit developing suburbs in all directions, so that they can develop as high-density transit-oriented communities, and not as low-density auto-oriented ones.
Asymmetric Mode Choice
In most models I have seen, ridership and mode choice are assumed to be symmetric: if I take the bus to work, I will also take it back home. Of course those models distinguish home from work: if a bus is full inbound in the morning it’s not expected to be full outbound in the morning. But the assumptions are that if the bus is full inbound in the morning, it should be full outbound in the afternoon. To a first-order approximation this is fine, but there are multiple situations in which people can choose differently in each direction. This is less relevant when discussing cars and bikes, because if you use them in one direction you must use them in the other, but it’s relevant to car-share, bike-share, various kinds of buses and trains, walking, and flying.
Most of this post will take the form of anecdotes. I have not seen any model that accounts for these cases, or any discussion elsewhere. The only exception is when large changes in grade are involved: people walk or bike down more easily than up, and this means that in bikeshare systems, the operators sometimes have to tow bikes back to high-elevation neighborhoods because people persistently take them downhill more than uphill. However, in addition to asymmetry caused by physical geography, there’s asymmetry caused by urban layout and transit system layout, as well as asymmetry caused by different characteristics of trips.
Case 1: Frequency Splitting
Consider the above image of a transit network. Point A is a major destination; area D is a neighborhood, and point E is an origin. The thick black line is a rapid transit line, passing through and stopping at B, C, and E. The red and blue lines going east from A are frequent rapid bus lines. The gray line going from A to E is a lower-grade bus line: less frequent, and/or slower.
In this image, traveling between A and either D or E, the frequent buses will be more useful going away from A than toward A. For an A-D trip, if I live in neighborhood D and travel to A, then I need to choose which of the two parallel streets to stand on, whereas going back from A to D, I can stand at the bus terminal and take whichever bus comes first. For an A-E trip, if I live at E and am going to A, then again I need to choose which of the two bus lines to use, that is whether to get off the rapid transit line at B or C, whereas going back this is not an issue. On the margin, I might choose to take the lower-grade but direct bus from E to A but not back.
Neither of the situations is hypothetical. When I went to college at NUS, my situation was similar to the A-E case: while the subway has since reached campus, in the mid-2000s the campus was connected by buses to two separate subway stops, Clementi and Buona Vista, and although some parts were definitely closer to one than to the other, the connecting buses served all parts of campus relevant to me. There was no equivalent of the gray bus, and I’d almost always take a taxi to campus, but usually take transit back. Now that I’m in Vancouver and work at UBC, where bus lines converge from parallel east-west streets, my situation is similar to the A-D case, since I can take Broadway buses as well as 4th Avenue buses; there is no alternative to the buses for me, but if there were, for example bikeshare, or walking if I lived closer to campus, I might well use it.
In those examples the asymmetry is for the most part unavoidable, coming from urban layout. In Vancouver, there are multiple east-west streets on the West Side that deserve frequent bus service. Consolidating everything on one street can come from the opening of a Broadway subway to UBC, but because the asymmetry is a second-order effect, the main argument for the subway has little to do with it.
Case 2: Waiting Facilities
Some bus and train stations are notorious for being unpleasant to wait at. Tel Aviv’s Central Bus Station is dark and labyrinthine. In New York, Penn Station and Port Authority are both unpopular. Many older airports are infamous for their poor amenities and confusing layouts. Because people need to wait going outbound but not inbound, this could affect mode choice.
In Vancouver, UBC has two separate bus loops, one for generally express diesel buses, and one for local electric buses; each loop has buses going on multiple streets, as in the above image. I find the diesel loop noisy and disorienting, and therefore avoid it, waiting at the electric loop or the next stop after the loops. Therefore, I usually take electric buses back home from UBC, while I almost always take diesels toward UBC. I have no direct experience with Kennedy Plaza, but other Providence-based bloggers think little of it; I think it was Jef Nickerson who noted that buses going on the same trunk routes are not co-located there. This could induce a similar asymmetry.
It gets worse when bus stops do not have shelter from the elements. Sheltered stops should be included in any bundle of best industry practices, but when they are present only downtown or at major stations, they can bias me to take the bus in just one direction.
Transit agencies can eliminate this asymmetry by making their facilities better. Usually the cost of shelter, clear signage, a bus bay layout that makes identifying the correct bays easy, and similar improvements is negligible, and the benefits are large. Of course, independently of any asymmetry there is no excuse for not having passable facilities, but in some cases, such as the UBC diesel loop, the situation on the ground is worse than it appears on planning maps and this worsens the passengers’ experience.
Case 3: Stress for Time
For some trips – going to an airport or intercity train or bus station, going to a meeting, going to class, going to a workplace where I need to be there at a specific time – there’s a more pressing need for timeliness in one direction than in the other. This biases in favor of more punctual or faster vehicles, even if they’re more expensive or less pleasant. This manifests itself in airport choice (when flying out of New York, I strongly prefer rail-accessible JFK, while my preference for flying in is much weaker), willingness to transfer to save a few minutes of trip time, willingness to ride a more expensive but faster train (for example, the LIRR versus the E), and bus versus train decisions (trains are almost invariably more reliable, often by a large margin). The few times I used transit to get to NUS, I used the subway, whereas when I went back home I’d often use a trunk bus, which was slower but had a station much closer to where I lived.
In this case, there’s not much the transit agency can do. If the bus versus rail issue is persistent, the best thing that can be done is encourage more mixed-use zoning and more symmetric morning travel demand, so that buses would be used in both peaks and not just in the afternoon peak and vice versa for trains.
Case 4: One-Way Routes
To the extent that the transit activist community has an opinion, it is strongly against one-way pairs, going back at least to Jane Jacobs’ criticism in The Death and Life. I’ve written briefly about them; Jarrett has written more extensively. One more issue is that if a bus route runs one-way on different streets (as a consistent one-way pair as in New York, or in a more complex arrangement as in Tel Aviv and Singapore) and I live closer to one direction than to the other, I might take it in just one direction. In Tel Aviv it was not a major problem because the bus I took to middle school run two-way in the segment relevant to me, but in Singapore it was an issue in both middle school and college: I lived next to a very wide one-way street without nearby crosswalks, and getting to the other direction of the buses required crossing it and walking some extra distance; this helped bias me for taking the bus only in the return direction.
The Effects on the Margins
Since asymmetry is small enough an effect that models can ignore it and still come very close to predicting actual ridership, its effect on transit planning is only on decisions that are very close to begin with.
I believe the most common case is the one in the image. A city that transitions from an idiosyncratic network of infrequent direct buses to a regular frequent grid where passengers are expected to transfer needs to decide which of the infrequent buses to keep. It might even have a few peak-only express buses it is considering keeping. In this case, it’s useful to note in which directions the infrequent or peak-only buses are more likely to get passengers, and potentially have an asymmetric number of trips on those in each direction, recycling the equipment for nearby routes whose asymmetry goes in the other direction.
Construction Costs and Perceptions
While looking for South Korean cost data for a major update of my construction costs posts, I stumbled upon a newspaper article excoriating Seoul’s extravagant construction, comparing it unfavorably with the US. Per Joong-Ang, the US neglect of infrastructure is a form of frugality that South Korea should imitate; the National Mall’s poorly maintained, weedy lawns are treated as something to admire. Moreover, Seoul subway construction is more extravagant than in the Washington Metro:
I got on a train at the Smithsonian Metro station. All the stations there have the same architectural styles. They are the 1976 creation of American architect Harry Weese. High ceilings and open spaces are their trademarks. They are known for their practicality. But they are very modest compared to the subway stations of Seoul. The platforms are dimly lighted. It’s hard to read a book there. The walls are concrete, with none of Korea’s flashing signboards. The architecture is very quiet.
After I returned to Seoul, I got on the subway at Guryong Station in Gangnam District, southern Seoul. Marble proliferates at the entrance. A public table is covered with glass. Every day, about 3,600 people use the station, which cost 55 billion won ($51.2 million) to build.
Of course, in reality, Korean construction costs are a fraction of American ones. Guryong Station is an infill subway station in a dense urban neighborhood, opening about a year after the rest of the Bundang Line; it cost about $75 million in 2010 PPP dollars. The US sometimes builds at-grade infill commuter stations for more than that, and those do not have marble entrances or glass tables (update: New York Avenue in Washington is another example of more expensive US infill, this time an elevated station). Building just the shell of an infill subway station on the 7 extension simultaneously with the rest of the extension was estimated at $500 million. Similarly, the Sin-Bundang Line, a driverless rapid transit line, cost 1,169 billion won, about $1.4 billion, for about 18 km; the line is described as “largely underground,” fully underground, and its city terminus is under a dense secondary CBD. In contrast, in Washington, the suburban Silver Line, with very little tunneling, is $6.8 billion (in 2009-2018 dollars) for 37 km. $183 million per km versus about $80.
There are two takeaway lessons from this. The first is that to gauge whether something is cheap or extravagant we need to know the normal range of costs and compare, rather than looking at the quality of construction. Seoul may build very extravagant-looking stations, but it builds them cheaply for some reason.
The second, more important lesson is that people perceive costs the way they perceive local corruption. The US is indeed the world’s most expensive country to build transit in, which Americans can easily believe since they do not trust their government very much. At the opposite corner, Switzerland is quite cheap: a rejected mountain tunneling project in Neuchatel was CHF 850 million for 17 km, and a recently completed urban tunnel in Lucern was CHF 250 million for 1.32 km; accounting for the Swiss franc’s 87% overvaluation relative to PPP, these are $28 and $121 million per km respectively. And as far as I hear from Swiss commenters, the Swiss are proud of the success of their public transportation system. Indeed, Swiss levels of trust in government and institutions are very high.
In contrast, in cheap countries where people do not trust the government, people do not readily accept that construction costs are low. When I talk to Spaniards who are not railfans, they talk about corrupt and extravagant infrastructure projects, and do not believe that both high-speed rail and subway construction costs in Spain are so low. (It doesn’t help that Barcelona’s L9/10, despite still being about average-cost, went over budget by a factor of over 3.) This is no different from the Joong-Ang attitude toward Korean costs: the government self-evidently doesn’t work, and so a $75 million infill subway station is self-evidently a boondoggle.
The situation in the opposite corner – high trust/low perceptions of corruption, high costs – exists as well, in Singapore. The sixth MRT line, soon to begin construction, is S$18 billion for 30 km; the PPP exchange rate between Singapore and US dollars is about 1:1. The line is automated and fully underground, but about half of it is under very wide arterial roads and portions of it are in undeveloped rather than built-up land; it shouldn’t cost this much. The fifth line, currently under construction, is cheaper, S$12 billion for 40-42 km, but still much more expensive than the non-Anglophone average.
And yet, although Singapore’s not far behind Japan in its construction costs, I doubt Singaporeans are as willing to consider their construction practices expensive as Americans, Britons, and Japanese are. I know for a fact that international commentators who hold Singapore in high regard for its efficient government would not be willing to think of it as an expensive-construction country.
All this makes good transit activism somewhat frustrating, in that people will not usually recognize efficient government in absolute numbers. Percentages, certainly – people understand cost overruns and (much less common) cost underruns, and as we’ve seen in Canada people can compare different technologies. But absolute numbers are not as well-understood, and neither are international comparisons of the same technology, where cost differences revolve around questions of project management, contracting practices, labor rules, and details of geology and surrounding infrastructure; people have only recently begun to think in terms of per-km costs in New York, and in the rest of the US I have not seen such thinking. When a transit agency proposes a project, people automatically think it’s expensive, and some will also say it’s necessary, regardless of whether it actually is either. I don’t think reactions to Second Avenue Subway at $5 billion would be materially different from what they were when Phase 1 alone grew to $5 billion.
The upside is that in budget negotiations, the amounts given to transportation are based on absolute shares of the budget rather than on the needs of specific megaprojects, which means that lower costs would translate to more projects built for the same budget. People might not notice that costs have gone down, and might still complain that every subway line is a boondoggle, but more lines would be built and more people would ride those lines. Just the perception of government competence would not change.
Branching
S-Bahns and similar systems have two defining features. One has been hashed to death on this blog: they reuse legacy rail lines, allowing urban rapid transit to extend arbitrarily deep into suburbia. The other, common also to many other transit technologies, is that they branch extensively, allowing them to run many services on the outer ends, where there’s no demand for rapid transit frequency, while interlining to produce high frequency in the center, where there is.
Since branching is a service planning decision independent of technology, any technology could branch. The branching-friendliest technology is subway-surface: the central subway segment has higher capacity measured in trains per hour than the outer surface segments, and this requires branching. For examples, consider the Boston Green Line, Muni Metro, the Frankfurt U-Bahn, and SEPTA’s Subway-Surface lines. However, even when the entire line is rapid transit, branching is useful to ensure higher service where there is higher demand, and infrastructure improvements will typically focus on boosting capacity in the center. For example, the RER A has moving-block signaling allowing 30 peak-direction trains per hour in the center, but fixed-block signaling on the branches, which do not need such capacity.
Even when rapid transit is built separate from both light rail and mainline rail, branching is useful for lines going into the suburbs or even outer-urban neighborhoods. This is practiced in both New York and London, both of which have extensive branching. Observe further that in both cities, the lines reaching farthest out – the A in the Queens-bound direction and the Metropolitan line in the west – are also the most highly branched.
It’s the opposite situation that is weird. When lines do not branch, there must be a strong outer anchor, or else trains need to run empty outside the center. The alternative is short-turns, and if there’s no space for this, the resulting service patterns can be awkward. Shanghai, which has little branching, runs Line 2 in two segments, a central segment with higher frequency and longer trains and an eastern one with lower frequency and shorter trains; trains do not run through. Beijing has a similar awkwardness with the split between Line 1 and the Batong Line, and Toronto has a split between the Bloor-Danforth line and the technologically incompatible Scarborough rapid transit. (The Sheppard line suffers from the same problem today, but it has the excuse that it was planned to continue west to the Spadina subway rather than stub-ending at Yonge.) Paris has little branching on the Métro as well, but the Metro only serves inner parts of the metro area, many lines have strong outer anchors (for example, La Défense on Line 1), and two others providing some of the farthest-out service branch. The RER branches much more heavily, as befits a suburban system. Tokyo has little branching on the subway proper, but the subway is for the most part inner-urban, and lines continue to the suburbs along commuter lines, which do branch.
In North America, this configuration has been common across a variety of new-build systems, especially ones that should have been S-Bahns. BART does this the most extensively, but the Washington Metro is also highly branched for its size, MARTA branches, the light rail systems branch once more than one line is built, and so on. BART in particular imitated the service planning aspect of commuter rail perfectly, and is an S-Bahn in all but the cost of extending the system further.
The problem with any branching is that it reduces frequency on the branches, potentially scaring away ridership. When a single rapid transit line splits in two it’s rarely a problem, and when city-center service splits into suburban services even more is easy to justify. I think the main issue in urban or inner-suburban cases is that with typical rapid transit frequencies (3-minute peak service or slightly better, a peak-to-base ratio of 2:1 or somewhat less) the trunk has about 5-minute off-peak service, and if it splits into two branches, this means 10-minute service on the branches. If the branching occurs early enough that dense neighborhoods with short-distance travel demand are on branches, it may be too little. In addition, if one branch has much more demand than the other, then it’s usually hard to match frequency on each branch to demand, since it requires trains to be unevenly spaced.
The issue is that branch frequency, 10-15 minutes, is in the transition zone between urban show-up-and-go frequency, where schedules do not matter, and suburban frequency, where they do. It’s perhaps less relevant in small cities with small enough transit systems that even 10-minute service is considered very good, but in large cities, people expect more, creating somewhat of an inner-urban metro envy effect.
That said, 10-minute suburban and outer-urban service can be done clockface, making the average wait much smaller. It is done on the RER A in the midday off-peak, with three 10-minute branches, and could be done with two 10-minute branches quite easily. Likewise, it could be done for 15-minute branches (the RER B already does this); the two A branches in New York have close to 15-minute frequency each, and if New York City Transit’s service planning considered it as a factor instead of focusing more on headway management it could ensure predictable schedules at Ozone Park and the Rockaways.
Transit and Place
There is a large class of transit supporters who think that every right-of-way that can be used for transit should be preserved for this purpose, even if it is not very useful. A few overzealous railfans on the message boards opposed the opening of the High Line park and wanted the viaducts to be used for an extension of the 7 train. This is extreme and nowadays the transit activists I know support the High Line while opposing schemes to recreate it in an inferior context. But even serious bloggers like Cap’n Transit, Ben Kabak, and John Morris are opposing plans to create a Low Line out of the abandoned trolley terminal at the Essex/Delancey subway stop, on the grounds that it could be useful for transit one day.
Now, it’s possible that the Low Line idea is bad because people would not want to go to an underground park. But it’s not a problem for transit; the Williamsburg Bridge doesn’t need trolleys since it has a subway running on (and because the bridge is high there is no way a bus could cross it without passing within two blocks of Marcy, the subway stop at the Brooklyn end of the bridge). The lines running on it are in fact underused: as can be seen on PDF-pages 65-73 of the latest Hub Bound Travel Data report, peak-hour traffic on the J/M/Z entering the Manhattan core was one of the lower in the system as of 2010 – higher than the bottom two track pairs (8th Avenue local and Montague) but in a near-tie for third lowest with several others. So there’s not much use for the trolley terminal as a modern Williamsburg Bridge bus (or trolley) terminal.
But what is more important than just the Low Line is place. To succeed, transit needs not only to exist, which it already does in the area in question, but also to have places to connect to. If for some reason the trolley terminal would need to be demolished to build room for foundations for several skyscrapers, it would be an unambiguous win for transit, since it would create more destinations for people to take the existing J/M/Z and F trains to. The surrounding neighborhood might disagree regarding the implications for urbanism, though I’d argue that Midtown-like skyscrapers would be better-integrated into the streetscape than the projects east and south of the station. If the Low Line succeeds as a park, it will be similar: not in the sense of providing jobs for tens of thousands of people, but in the sense of creating a place for people to go to. (In fact, a park has less peaky demand than offices, so it could be better for subway finances even at relatively low levels of usage.)
Last year, I brought up the question of the infrastructure’s highest value mainly as a way of deciding which kind of service (regional, intercity, etc.) should get first priority on any given rail line, but the same is true about transit versus place. In an area with enough transit and not enough place, it’s more important to create more development, for both good urbanism and more successful transit.
This does not mean every proposal to turn a rail right-of-way into a park is good. Despite my skepticism that the Rockaway Cutoff can be a successful rail line, I’m even more skeptical about its value as a park; it’s not in an area that can ever draw many people, since the density (of both residences and jobs) is not high by New York standards and it is far from other destinations that could draw people from outside the nearby neighborhoods. However, in areas that are lacking in good parks, or could use new development, it is better to concentrate on creating place.
For examples of this elsewhere, consider the railyards in Long Island City, Hoboken, and Sunnyside. Two of my earliest posts proposed to build a regional rail station in Sunnyside and then develop the area around it with air rights over the railyard; this is what should be done in an area that needs both transit and place. But in Hoboken and Long Island City, there’s ample transit, and the only use of the railyards is to park trains that can’t do to Manhattan because of lack of electrification or lack of capacity in the approach tunnels. Since parking trains is an inefficient use of space, and both areas have good connections to Manhattan by subway or PATH, there should be plans to remove the railyards and redevelop them to create more place, leaving just enough rail infrastructure to run through-trains, to be parked in lower-value areas. This development can be either parkland or buildings, depending on what is in demand in the area. Based purely on Google Earth tourism, I believe Hoboken does not need additional parks and so development there should be just a new secondary CBD on top of the PATH station, while Sunnyside and Long Island do, and so development there should include parks as well as high-density office and residential construction.
Instead of worrying about turning unused and for the most part unusable transit infrastructure into place, good transit activists should focus on preserving infrastructure that could potentially be used. In the New York area, probably the most useful piece of infrastructure that isn’t currently used is the Bergen Arches, allowing the Erie lines to enter Jersey City at Pavonia/Newport, a more central location than Hoboken; this is one of four options for a location for a new regional rail tunnel from New Jersey to Lower Manhattan, and is arguably the best option for an integrated regional rail network.
In the 1990s there were plans to reuse the Bergen Arches for a roadway, since modified to include both a road option and a rail option, and in 2011 the Christie administration allocated some money to further studies; an analysis from 2004 scored various road and transit options, not including a regional rail network, and gave the highest score to a roadway with a single high-occupancy vehicle and bus lane per direction. (A trail got the second lowest score, after no-build.) Since Jersey City (and the entire region) needs more transit from the north and west, while further formation of place will and should cluster around the waterfront, it’s important to fight any plan to give the Bergen Arches to a non-railroad use unless and until a regional rail plan is formulated that places the New Jersy-Lower Manhattan tunnel at another location.
In contrast, the Low Line should not be a priority. On the contrary, if the park plan is even partially sound, or the place could be reused as another place if the park idea fails, then good transit advocates should support the idea, since it’d be good urbanism. With a few exceptions, good transit requires good urbanism and vice versa.
Relative Costs of Transit Construction
The relative costs of different technologies of transit are not fixed. Although there are some rules of thumb for the ratio of tunneling cost to above-ground transit cost, the actual ratio depends on the city and project, and this would favor the mode that’s relatively cheaper. Likewise, the ratio of operating to capital costs is not always fixed, and of course long-term real interest rates vary between countries, and this could again favor some modes: more expensive construction and cheaper operations favor buses, the opposite situations favor rail.
In general, els cost 2-2.5 times as much as at-grade light rail, subways 4-6 times as much, according to Table 6 in this Flyvbjerg paper; Table 5, sourced to a different previous paper, estimates per-km costs, and has ratios of 1.8 and 4.5 respectively.
However, specifically in Vancouver, the premiums of elevated and underground construction appear much lower. The cost estimates for rail transit to UBC are $2.9 billion for an almost entirely underground extension of SkyTrain and $1.1 billion for at-grade light rail along Broadway, both about 12 km. Elevated construction is in the middle, though closer to the light rail end: the estimates for the two all-elevated SkyTrain extension alternatives into Surrey are $900 million for 6 km for rapid transit alternative 3 and $1.95 billion for 15.5 km for alternative 1. The under-construction Evergreen Line, which is 11 km long of which about 2 are in tunnel, is $1.4 billion.
In the rest of Canada, this seems to be true as well, though the evidence is more equivocal since the projects that are considered above-ground are often elevated rather than at-grade. The Canadian above-ground projects that Rob Ford’s Eglinton subway is compared with are not wholly above ground. Calgary’s West LRT, which with the latest cost overrun is $1.4 billion (a multiple of the preexisting three-line system) for 8 km, includes a 1.5 km tunnel, a short trench, and some elevated segments. Edmonton’s North LRT is $750 million for 3.3 km, of which about 1 km is in tunnel and the rest at-grade. But while it’s hard to find the exact ratio because of those mixed projects, the costs are not consistent with the ratios found in Flyvbjerg’s sources.
Outside Canada, those ratios seem to hold up better. American above-ground transit projects, such as the Portland Milwaukie extension and the Washington Silver Line, are as expensive as Calgary and Edmonton’s light rail, but American subways are much more expensive than Toronto’s Eglinton subway ($325 million/km, 77% underground and the rest elevated): Manhattan tunneling is more difficult, so its $1.3-1.7 billion/km cost may not be representative, but conversely, BART to San Jose’s $4 billion for about 8 km of tunnel is for tunneling partially under a wide railroad right-of-way, with no crossings of older subway infrastructure as is the case for Eglinton at Yonge.
Conversely, French tunneling costs are comparable to or lower than Canadian ones, but at-grade light rail is far less expensive than in North America. The RER E extension was at least as of 2009 budgeted at €1.58-2.18 billion for 8 km of tunnel (see PDF-page 79 here; this excludes €620 million in improvements to the existing commuter lines the tunnel will be linked with) – somewhere between the per-km costs of Vancouver and Toronto subways, but in a much denser environment with more infrastructure to cross. But the cost range for Parisian trams is much lower, about €30-50 million per km, in line with the subway:tram cost ratio of 4-6; the cost range in other French cities tends to be a little lower.
What this means is that in Canada in general, and in Vancouver in particular, questions about what mode to build should have higher-end answers than elsewhere. It doesn’t mean that the Eglinton subway is justified, but it does bias suburban rail lines in Vancouver toward elevated SkyTrain extensions rather than light rail, and inner extensions toward SkyTrain subways. For the same cost of building a subway under Broadway, Translink couldn’t build too much additional light rail; it could build two lines, say on Broadway and 41st, or maybe three if both non-Broadway routes are short, but certainly nothing like the entire network that SkyTrain opponents believe is the alternative, citing European tramway construction costs.
Nobody Likes Riding North American Commuter Rail
In New York, two neighborhoods at the edge of the city have both subway and commuter rail service: Wakefield and Far Rockaway. Wakefield has 392 inbound weekday Metro-North boardings, and 4,955 weekday subway boardings. Far Rockaway has 158 riders (an average of boardings and alightings) and 4,750 subway boardings. Although both Wakefield and Far Rockaway are served by the 2 and A, which run express in Manhattan, those trains make many local stops farther out – in fact the 2 and A are the top two routes in New York for total number of stations – and are much slower than commuter rail: the 2 takes 50 minutes to get to Times Square while Metro-North gets to Grand Central within 25-30 minutes; the A takes about 1:05 to get to Penn Station, the LIRR about 55 minutes.
Vancouver, whose commuter rail service runs 5 daily roundtrips, all peak-hour, peak-direction, has a weekday ridership of 10,500. The Evergreen Line, duplicating the inner parts of the commuter rail service, is expected to get 70,000.
Caltrain, a service of intermediate quality between Vancouver’s peak-only trains and New York’s semi-frequent off-peak electrified service, has an intermodal station at Millbrae, which is now BART’s southern terminal. Millbrae has 5,970 BART exits per weekday versus 2,880 Caltrain boardings. And BART takes a circuitous route around the San Bruno Mountain and only serves San Francisco and the East Bay, while Caltrain takes a direct route to just outside the San Francisco CBD and serves Silicon Valley in the other direction.
The MBTA provides both subway and commuter rail service, with several intermodal stations: Forest Hills, Quincy Center, Braintree, Porter Square, Malden, JFK-UMass. In all cases, ridership levels on the subway are at least 30 times as high as on commuter rail. Rapid transit and commuter rail stations are close together at the edge of the Green Line’s D line, a former commuter line; the line’s outer terminus, Riverside, gets 2,192 weekday boardings, while the nearest commuter rail station, Auburndale, gets 301.
Across those systems and several more, such as Chicago’s Metra and Toronto’s GO Transit (no link, it’s private data), the commuter rail stations located within city limits, even ones not directly adjacent to a rapid transit station, usually get little ridership (there are some exceptions, such as Ravenswood on Chicago’s UP-N Line). The suburban stations beyond reasonable urban transit commute range are much busier.
Of course, this is just a North American problem. In Japan, where commuter rail and urban rapid transit are seamlessly integrated, people ride commuter rail even when the subway is an option. Consult this table of ridership by line and station for JR East lines in Tokyo: not only would any investigation of ridership on the main lines (e.g. Tokaido on PDF-page 1, Chuo on PDF-page 8) show that their ridership distribution is much more inner-heavy than in New York and Boston, but also stations with transfers to the subway can have quite a lot of riders. Nakano on the Chuo Line, at the end of Tokyo Metro’s Tozai Line, has 247,934 daily boardings and alightings, comparable to its subway traffic of 133,919 boardings.
Although my various posts about commuter rail industry practices focus partially on operating costs, this is not directly what makes people choose a slower subway over a faster commuter train. Rather, it’s a combination of the following problems:
1. Poor service to microdestinations. Rapid transit gets you anywhere; North American commuter rail gets you to the CBD. For people in Wakefield who are going anywhere but the immediate Grand Central or East 125th Street area, Metro-North is not an option. Station spacing is too wide, which means the choice of destinations even from a station that isn’t closed is more limited, and trains usually make just one CBD stop.
2. Poor transfers to other lines. The transfers usually require paying an extra fare and walking long distances from one set of platforms to another.
3. High fares. In the German-speaking world, and in Paris proper, fares are mode-neutral. It costs the same to ride the RER as the Metro, except for a handful of recent Metro extensions to the suburbs that postdate the RER, such as to La Defense. In Japan, JR East fares are comparable to subway fares, though there are no free transfers. In North America this is usually not the case: it costs much more to ride commuter rail than to ride a parallel subway or light rail line.
4. Low frequency. This is partly a result of low ridership based on the previous factors, partly a tradition that was never reformed, and partly a matter of very high operating costs. With low enough off-peak frequency (Wakefield and Far Rockaway are served hourly midday), commuter rail can achieve cost recovery similar to that of subways, and in some cities even surpass it. People who have no other options will ride hourly trains.
None of those problems is endemic to mainline rail. They’re endemic to North American mainline rail culture, and in some cases to labor practices. It’s all organization – it’s not a problem of either electronics or concrete, which means that the cost to the taxpayers of fixing it, as opposed to the political cost to the manager who tries to change the culture, is low.
The electronics and concrete do matter when it comes to building extensions – and this is where the ARC Alt G vs. Alt P debate comes from, among many others – but even commuter rail systems that do not need such extensions underperform. For example, Toronto does not need a single meter of commuter rail tunnel. Philadelphia, which already got most of the concrete it needs and partially fixed the microdestination problem, gets somewhat more commuter rail ridership in areas where people have alternatives, but frequency on the branches is still pitiful and inner-city stop spacing outside Center City is still too wide, leading to disappointing ridership.
Another way to think about it is that infrastructure should be used for everything, and not segregated into local transit and railroad super-highways that aren’t very accessible to locals. There are eight tracks connecting Manhattan directly with Jamaica, but the four used by the subway are far busier than the four used almost exclusively by suburbanites. Something similar is true of the Metro-North trunk, and some MBTA and Metra lines – the commuter rail infrastructure is redundant with rapid transit and gives very high nominal capacity, but in reality much of it is wasted. In this way, the mainline rapid transit concept including the Paris RER, the Germanic S-Bahn, and the Japanese commuter rail network, far outperforms, because it mixes local and regional traffic, creating service that everyone can use.
Are Forecasts Improving?
In response to my takedown of Reason, specifically my puzzlement at the estimates of inaccuracy in traffic forecasts, alert reader Morten Skou Nicolaisen sent me several papers on the subject. While there is past research about traffic shortfalls, for example this paper by Flyvbjerg (hosted on a site opposing the Honolulu rapid transit project), Flyvbjerg’s references are papers from twenty years ago, describing mostly subway projects in developing countries, but also rapid transit and light rail projects in the US built in the 1970s and 80s. Unlike Flyvbjerg, who posits that planners are lying, the authors of the papers he references have other theories: currency exchange rate swings, the challenges of underground construction, inaccurate forecasts of future economic growth, outdated traffic models based on postwar road traffic models. See section 6 of Walmsley and Pickett, and sections 3.3 and 4.2 of Fouracre, Allport, and Thomson (see also the range of costs for underground construction in developing countries in section 3.3).
The question is then whether things have improved since 1990. Since the first study to point out to cost overruns and ridership shortfalls in the US was by Pickrell, the question is whether post-Pickrell lines have the same problems, or whether there are better outcomes now, called a Pickrell effect.
The answer, as far as ridership is concerned, is very clearly that ridership shortfalls are no longer a major problem. See recent analysis by Hardy, Doh, Yuan, Zhou, and Button; see specifically figure 1. Cost overruns also seem to be in decline and are no longer big, although a multiple regression analysis finds no Pickrell effect for cost, just for ridership.
In particular, there is no comparison between projects from 30 years ago, most of which are underground, and present-day developed-world high-speed and urban rail lines.
Pedestrian Observations 
