What would it take to improve public transportation in New York so that all or nearly all routes would run at worst even six minutes during midday? Today, frequencies are tailored to individual routes; a bunch of subway lines are a 10-minute city (and the A branches are a 15-minute city), and in Brooklyn, the median midday bus headway is 12 minutes, with wide variations.
The bus origin of six minutes
Six minutes is not an arbitrary number. It comes from Eric’s and my Brooklyn bus redesign; speeding up routes through stop consolidation, dedicated lanes, and off-board fare collection, and pruning and recombining some routes, lets every bus run every six minutes from 6 am to 10 pm all day every day, with higher frequency on those routes that already have it today because they are too busy for just ten buses per hour. We didn’t study the other boroughs as deeply, but a quick doodle suggested the six-minute standard could be met in Manhattan and the Bronx as well, and a Bronx bus grid could even dip into a five-minute city.
Queens is a wildcard and I’m going to disappoint readers by not talking about it. It is clearly possible given the operational treatment we propose to make most of Queens a six-minute city, but at the price of long route spacing in Eastern Queens, and I don’t know what is optimal. It’s a hard question and I’m not going to tackle it unless I’m actually working on a longer-term project to do a Queens bus redesign.
Six minutes on the subway
The subway right now is a 10-minute city. A lettered or numbered route runs every 10 minutes off-peak, sometimes every 12 on Sundays and at night; the busier routes, especially the four that do not share tracks with other routes (1, 6, 7, L), run more frequently, but 10 minutes is the base frequency on large swaths of the network. The A branches in Ozone Park and the Rockaways even run every 15 minutes, but that’s unusual enough – evidently, nowhere else does one letter or number denote a route with its own branches – that it can be excluded.
For comparison, Berlin’s rail network is a 10-minute city, with some outer S-Bahn branches running every 20 minutes. Within the Ring, Berlin is a 5-minute city for the most part, excluding just a two-hour midday dip to 10 minutes on the Ring and 10-minute frequencies on the U1/U3 branches and the practically useless U4 route. Paris makes no effort to run different routes at the same intervals – French rapid transit planning has self-contained lines with their own fleets and schedules, so for example the RER A is on 10-minute off-peak takts and the RER B on 15-minute ones. So frequency there greatly depends on where in the region one lives and on what line. The Métro is a 5-minute city for the most part, as are the intramural RER trunks; intramural buses can be ignored. The suburbs are more or less a 15-minute city.
The reason New York is a 10-minute city on the subway is partly about interlining. The trunks in theory run every 5 minutes or better, but the trains do not come evenly because sometimes trains with different frequencies share the same trunk, and delays propagate easily. Interlining really doesn’t work unless all trains come at the same frequency; this is familiar in German planning, but not in American planning (or French planning, but there’s barely any interlining in Paris).
Putting every subway route on a 10-minute takt, with double service on the four non-interlined services, is possible but would lead to a lot of crowding on the busiest lines. About the worst possible frequency that works for everything is a train every 7.5 minutes; this lets the two A branches run on 15-minute takts, and everything else run on a 7.5-minute takt. But even then, New York has so many missed connections that it’s useful to do better. The six-minute city, matching buses, turns most of Manhattan and inner Brooklyn and Queens into a three-minute city.
Running all trains on the same takt also means timed connections. Trains that run every 5 or 6 minutes can routinely be timetabled to be at predictable places at predictable times, which facilitates local/express transfers on branches, for example in Southern Brooklyn. Even trunk transfers can be timed – 3-minute trains can still run on a timetable, and the most valuable transfers are local/express ones at 96th/Broadway, 125th/St. Nicholas, and 125th/Lex, all far enough north so as to not have the huge tidal crowds of Times Square or Grand Central.
What would it take?
On the buses, just good redesign, as long as the city is willing to exclude Staten Island from the six-minute city. In Queens, some increase in bus service is probably warranted.
On the subway, this requires on the order of 110-120 million revenue train-km a year, which is 1 billion car-km. The current figure is 560 million car-km/year. There is a lot of unnecessary expenditure on the subway, but fixing that requires something a lot deeper than a bus redesign. The cut in operating costs would be to levels that are well within first-world levels, and some of it would just come from better off-peak service making crew scheduling easier, without split shifts or wasted time. But it does require serious changes, especially in maintenance.
Outside a city core with very high frequency of transit, say 8 minutes or better, bus and train services must be timetabled to meet each other with short connections as far as possible. Normally, this is done through setting up nodes at major suburban centers where trains and buses can all interchange. For example, see this post from six months ago about the TransitMatters proposal for trains between Boston and Worcester: on the hour every half hour, trains in both directions serve Framingham, which is the center for a small suburban bus system, and the buses should likewise run every half hour and meet with the trains in both directions.
This is a dendritic system, in which there is a clear hierarchy not just of buses and trains, but also of bus stops and train stations. Under the above system, every part of the Framingham area is connected by bus to the Framingham train station, and Framingham is then connected to the rest of Eastern New England via Downtown Boston. This is the easiest way to set up timed rail-bus connections: each individual rail line is planned around takt and symmetry such that the most important nodes can have easy timed bus connections, and then the buses are planned around the distinguished nodes.
However, there’s another way of doing this: a bus can connect two distinct nodes, on two different lines. The map I drew for a New England high- and low-speed rail has an orbital railroad doing this, connecting Providence, Worcester, and Fitchburg. Providence, as the second largest city center in New England, supplies such rail connections, including also a line going east toward Fall River and New Bedford, not depicted on the map as it requires extensive new construction in Downtown Providence, East Providence, and points east. But more commonly, a connection between two smaller nodes than Providence would be by bus.
The orbital bus is not easy to plan. It has to have timed connections at both ends, which imposes operational constraints on two distinct regional rail lines. To constrain planning even further, the bus itself has to work with its own takt – if it runs every half hour, it had better take an integer multiple of 15 minutes minus a short turnaround time to connect the two nodes.
It is also not common for two suburban stations on two distinct lines to lie on the same arterial road, at the correct distance from each other. For example, South Attleboro and Valley Falls are at a decent distance, if on the short side, but the route between them is circuitous and it would be far easier to try to set up a reverse-direction timed transfer at Central Falls for an all-rail route. The ideal distance for a 15-minute route is around 5-6 km; bus speeds in suburbia are fairly high when the buses run in straight lines, and if the density is so high that 5-6 km is too long for 15 minutes, then there’s probably enough density for much higher frequency than every half hour.
The upshot is that connections between two nodes are valuable, especially for people in the middle who then get easy service to two different rail lines, but uncommon. Brockton supplies a few, going west to Stoughton and east to Whitman and Abington. But the route to Stoughton is at 8.5 km a bit too long for 15 minutes – perhaps turning it into a 30-minute route, either with slightly longer connections or with a detour to Westgate (which the buses already take today), would be the most efficient. The routes to Whitman and Abington are 7 km long, which is feasible at the low density in between, but then timetabling the trains to set up knots at both Brockton and Abington/Whitman is not easy; Brockton is an easy node, but then since the Plymouth and Middleborough Lines are branches of the same system, their schedules are intertwined, and if Abington and Whitman are served 15 minutes away from Brockton then schedule constraints elsewhere lengthen turnaround times and require one additional trainset than if they are not nodes and buses can’t have timed connections at both ends.
Planners then have to keep looking for such orbital bus opportunities. There aren’t many, and there are many near-misses, but when they exist, they’re useful at creating an everywhere-to-everywhere network. It is even valuable to plan the trains accordingly provided other constraints are not violated, such as the above issue of the turnaround times on the Old Colony Lines.
I recently found myself involved in a discussion about Boston regional rail that involved a proposal to do more thorough regional rail-subway integration. Normally, S-Bahn systems mix some aspects of longer-range regional rail and some aspects of urban metro systems. They provide metro-like service in the urban core – for example, Berliners use the the three trunk lines of the S-Bahn as if they were U-Bahn lines. But, unlike proper metros, they branch in the suburbs and tend to have lower frequency and lower quality of infrastructure. However, there is a limit to this integration, coming from timetabling.
The characteristics of metro-like S-Bahn
When I call some S-Bahns, or some S-Bahn trunks, “metro-like,” what I mean is how users perceive them, and not how planners do. A metro line is one that users get on without concern for the timetable. It may run on a clockface schedule, for example on a 5-minute takt in Berlin, but passengers don’t try to time themselves to get on a specific train, and if the train is 1-2 minutes behind schedule then nobody really minds. This user behavior usually comes from high frequency. However, in New York, despite extensive branching and 10-minute frequencies, I classify the subway as fully metro-like because the trains are not dispatched as a scheduled railroad and even if they were, passengers don’t ever think in terms of “my Queens-bound N train arrives at :06 every 10 minutes.”
S-Bahn lines have trunks like this, but also branches that work like regional rail. The regional rail pattern in the sense of RegionalBahn is one in which passengers definitely look at timetables and try to make them, and connecting public transit lines are planned to make timed transfers. On lines branded as RegionalBahn service comes every half hour or every hour, and usually S-Bahn tails are every 15-30 minutes (occasionally 10), but the printed schedule is paramount either way; when I rode the RER B to IHES in the last three months of 2016, I memorized the 15-minute takt and timed myself to it.
The key aspect of S-Bahns is combining these two patterns. But this leads to a key observation: they have to interline a number of different service patterns, which requires planning infrastructure and service to permit both. They can’t run on pure headway management in the core, because the branches must be scheduled. But they have to use a timetabling system that permits high core frequency nonetheless.
Finally, observe that I am not discussing the type of equipment used. A subway train that extends far into the suburbs may qualify as regional rail – the Metropolitan line in London qualifies as an example on account of its highly branched service pattern in Metro-land. In the other direction, a train built to mainline standards that runs consistent service pattern with little to no branching at a range typical of metros is not, for the purpose of this issue, regional rail – examples include the Yamanote and Keihin-Tohoku Lines in Tokyo, which run identical trains to those that run deeper into suburbia but have literally no (Yamanote) or almost no (Keihin-Tohoku) variation in service patterns.
The limit of interlining
A large degree of interlining tends to reduce timetable reliability. Trains have to make junctions at specific times. This is compounded by a number of different factors:
1. Trunk throughput
The busier the trunk is, the harder it is to keep everything consistent. If you run 15 trains per half-hour, that’s 15 opportunities for a 2-minute delay to mess the order in which trains arrive, which has implications further down. If you run 4 trains per half-hour, that’s 4 opportunities, and a 2-minute delay is easily recoverable anyway.
2. Trunk length
Longer and more complex trunks introduce their own problems. If many passengers treat trains as interchangeable and don’t care what order they arrive in, then this may not be good for timekeeping – a slight delay on a branch may lead to grossly uneven headways on the trunk, which compound on busy metro lines for similar reasons as on buses. Berlin’s Stadtbahn has 14 stations from Ostkreuz to Westkreuz counting both, and this may make the branches with their 20-minute frequencies a little too difficult to fit together – evidently, peak throughput is 18 trains per hour, hardly the cutting edge. The RER A has 7 trunk stations from Vincennes to La Défense inclusive, and around 27 peak trains per hour.
3. Branch infrastructure quality
In the limit, the branches have to have excellent infrastructure quality, to be resilient to 1-2 minute delays. Timed meets on a mostly single-trunk line, routine on 15-minute branches like some lines in suburban Zurich and Tokyo, become dicey on lines that feed very busy trunks. Tokyo does this on the Yokosuka Line, which is far from the busiest (it peaks around 20 trains per hour) and Zurich on the right bank of Lake Zurich, which feeds into an S-Bahn trunk with 4 stations inclusive from Stadelhofen to Oerlikon. The busiest S-Bahn lines tend to have all-doubled outer ends.
4. One vs. two ends
If the line is single-ended, then inbound trains can just run metro-style in city center without regard for the printed schedule, use the terminal for schedule recovery, and then go outbound on schedule. Non-through-running lines are by definition single-ended, and this includes what I believe is Tokyo’s busiest regional rail line, the Chuo Rapid Line. But even some through-running lines are de facto single-ended if demand is highly asymmetric, like the Stadtbahn, which has far more demand from the east than from the west, so that one branch even turns at Westkreuz. Double-ended lines do not have this opportunity for recovery, so it’s more important to stay on schedule, especially if the end is not just busy but also has extensive branching itself.
Eric and I recently sent in a list of criteria for case selection. We’re currently funded for 6 detailed case studies, of which one is the Green Line Extension in Boston due to funding from a different grant. My guess is that we need about 15-20 different cities to have near-perfect information about the institutional and geographic factors that influence infrastructure construction costs. Because different subway lines in the same city tend to cost the same to build, and even in the same country, our 500 lines in the database are more like 50 independent observations, and there are even identifiable clusters of countries.
These clusters are important, because ideally we should have 2 cases per cluster. With 6 cases in total, we’d like to have a case for at least one per cluster, even though it’s unlikely, depending on where we can find the most detailed information and the most people who will talk to us.
1. Very low-cost countries
The first cluster is the success cases. These really come in two flavors: one is Switzerland and the Nordic countries, and the other is everywhere else with costs lower than $150 million per km, that is Spain, Portugal, Italy, Greece, Bulgaria, Turkey, and South Korea. The difference between the two flavors is that the first one consists of very high-wage countries with populations that trust their institutions, and the second consistent of countries with wages at the bottom of the first world or top of the second with populations who don’t believe me when I tell them their infrastructure construction is cheaper than in Germany. Even then, there are some important differences – for example, contracts in Turkey are lowest-bid, using the country’s high rate of construction and multitude of firms (a contract must have a minimum of 3 bids) to discipline contractors into behaving, whereas Spain instead has technical scoring for bids and only assigns 30% weight to cost.
2. Middle-range countries
This is countries close to the global average, which is around $250 million per kilometer for underground construction. China has about the same average cost as the rest of the world, and since a slight majority of our current database is Chinese, it falls in this category. France and Germany are definitely in this category; Austria, Czechia, and Romania are also in this category but have fewer distinct metro tunnels; Japan may be in this category but it’s unclear, since the few tunnels it’s building nowadays are both more expensive and more uniquely complicated, rather like regional rail. Big parts of Latin America fall into this category too, though they bleed with the high-cost category too. There’s a good case for separating China, France, Germany, and Japan into four separate categories (Austria should probably be institutionally similar to Germany), each of which gets different things right and wrong.
3. Countries with recent cost growth
This cluster consists of places that have high costs but didn’t until recently. Canada and Singapore are both competing for worst construction costs outside the United States but were not until well into the 2000s. Australia may be in this category too – it’s unclear, since Melbourne is extremely expensive to tunnel in but Sydney isn’t. New Zealand’s regional rail costs suggest it might be too – initial electrification was cheap but the regional rail tunnel is expensive. All of these countries share the characteristic of extreme cultural cringe toward Britain and the US, adopting recent British and American ideas of privatization of the state, and it would be valuable to follow up and see if this is indeed what happened with all of their infrastructure programs.
4. Rich countries with very high costs
This cluster is dominated by the US and UK. Taiwan is there too but is much smaller and likely has completely different institutional reasons – one person told me of political corruption. Hungary and Russia might be in this category too – they have very high costs (Budapest is scratching $500 million per km), but their wages are at the first/second world boundary, rather like Bulgaria or Turkey.
5. Countries on the global periphery with very high costs
This cluster consists of the high-cost world that is too poor or peripheral to be in cluster 4. This includes ex-colonies like India, Pakistan, Indonesia, Egypt, and Vietnam, but also the never- or more-or-less-never-colonized Gulf states; these two categories, the Gulf and the rest, must form two distinct flavors, but I lump them together because both seem to have extreme levels of cultural cringe and to associate bringing in European and East Asian consultants with modernity and success. (Meanwhile, parts of Europe, at least in the less self-assured East, bring in Turkish contractors.) The higher-cost Latin American countries, like Brazil and possibly Colombia, belong here too, and may form a distinct flavor. Thailand is on the edge between this cluster and cluster 2, which may befit its liminal colonial status before and during World War 2.
Where we struggle
We’ve been sending feeler messages to people in a number of places. This is far from perfect coverage – so far none of these countries is poorer than Turkey. In general, we’ve had early success in the lower-income range in cluster 1 (Italy, Spain, Korea, Turkey) and in cluster 4. Cluster 3 seems reachable too, especially since Stephen Wickens did much of the legwork for Toronto’s cost growth; we may be able to look at Sydney as well, and Singapore and Auckland seem like it shouldn’t be too difficult to find sources, nor to get people to listen if our conclusion ends up being “your government reforms in the last 15 years are terrible and should be reversed.”
Within the rich world, so far getting sources in Germany and Scandinavia has proved the hardest. I don’t know if it’s random or if it’s the fact that in countries that believe their standards of living are higher than those of the US and UK people are less likely to be forthcoming to someone who writes them in English. I’ve seen a decent amount of written material about rail capital construction projects in Germany, though not about the one I’m most interested in, that is the U5-U55 connection here in Berlin; but the rail advocates I’ve talked to are not quite in metro construction, though I have learned a lot about public transportation issues in Germany from them.
In Scandinavia things are even harder. Costs there seem pretty consistently low. A common explanation is that the rock in both Stockholm and Helsinki is gneiss, which forms a natural arch and makes tunnel boring easy, but a short tunnel in Oslo, the Løren Line, was even cheaper in softer rock. Moreover, the planned Helsinki-Turku high-speed rail is currently budgeted at €2 billion for 94 km of which 10 are in tunnel, so maybe equivalent to 140 km of at-grade line; this is noticeably below French costs, let alone German ones.
The low-income world is an entirely different situation. My suspicion is that the same cultural cringe that makes India build turnkey Shinkansen at something like 3 times its domestic cost (correcting for tunnel length) would make India eager to talk to us – if we were covered in the first-world discourse first. People in India, Nigeria, etc. know their countries are poor and are desperate to absorb the knowledge of richer places; they don’t understand the US as well as Americans do, but they understand it better than Americans understand the third world.
The reasons I’d ideally like to have 20 case studies are that there are a lot of questions about internal differences, and that things that look like clusters from cost data may not actually be similar. There are a lot of questions that doing more cases might explain.
- South Korea and Japan share many institutional similarities, and many of those are also shared with Taiwan. How come South Korea near-ties for lowest costs in the world, Taiwan near-ties for highest costs in the non-Anglophone first world, and Japan is somewhere in the middle?
- What explains why different Eastern European countries with similar histories and institutions have such cost divergence?
- Why does Italy have low metro construction costs (more in the North than in Rome and the South, but Rome is at worst average) and high costs of high-speed rail construction?
- Why does Japan have high metro construction costs where it builds and low costs of Shinkansen tunneling?
- Turkey seems similar in costs to Southern Europe, but it does things very differently – for one, it uses lowest-bid contracting. To what extent this is about Turkey’s very high rates of construction recently, and does this generalize elsewhere? Of note, there are extremely high construction rates all over middle-cost China, and also decently high rates in high-cost India, Singapore, and California.
- The Netherlands is institutionally within the same range of what’s seen elsewhere in Northern Europe, and yet its construction costs are high. Is this just a matter of alluvial soil tunneling? If so, why did HSL Zuid cost so much?
Our current project timeline includes posting the dataset of urban rail lines and their construction costs in a month. This means looking at various spreadsheets and checking them item by item. Part of it is checking for mistakes, which do unfortunately occur for some items. Sometimes even the sources have mistakes – for example, most sources for the Sinbundang Line in Seoul say it cost 1.169 trillion won (e.g. here, a bit higher in PDF-p. 60 here, and my now-linkrotted original source), but one says 1.69 trillion, which I’m fairly certain is a typo. However, the biggest source of errors in my file is that the majority of lines I included were under construction as of 2018, so cost overruns and schedule slips remain possible. And unfortunately, while a number of projects have significantly higher costs, the US is especially rich in cost overruns.
The case of Los Angeles is the most infuriating. It is not the highest-cost American city, not even close – nothing is within a factor of 2 of dislodging Second Avenue Subway Phase 2 from its throne. However, it’s making a strong bid for the second highest. The third phase of the Purple Line extension in the Westside, connecting Century City (reached in the second phase) with UCLA and the VA Hospital in Westwood, is $3.6 billion for 4.2 km. Costs have been creeping up from what used to start with a 2, and now this is $857 million per kilometer. This is in year-of-expenditure dollars, so in 2020 money it’s more like $800 million per km.
The contrast to what LA looked like in the 2000s is huge. In 2010-11, it looked like the lowest-cost US city; it was still really expensive to tunnel in, but it seemed more like $300-400 million per km. But things keep getting worse. If Canada and Australia and Singapore and Britain today are like the US 10-15 years ago, the US is pulling ahead, eager to be #1 in everything.
Of note, this is an environment with high and stable funding levels. Transit funding in Los Angeles is bonded through 2060. Contracts in Los Angeles are let on a lowest-cost basis; sometimes there’s a technical score, but officials at LA Metro told Eric and me that unless the weight of the technical score is very high, around 70%, then in practice the contract will go to the lowest bidder. Now, it is not true that all low-cost countries have high technical score weights like Spain does; Turkey in particular uses lowest cost, and uses its high construction rates to discipline bidders into behaving, since shoddy work will risk their ability to get future contracts. Nonetheless, in Los Angeles the great extent of construction does not involve any such discipline. Metro prefers dealing with familiar contractors, even if their record is poor.
Americans, as a culture, would rather die than be more like another nation. Taiwan’s last domestic corona infection was on April 12th, the US averages 60,000 such infections a day. The sort of change required to make Americans forget about 2 generations of learned public-sector helplessness is immense, and will not come spontaneously (and no, your chosen revolutionary movement won’t do it – revolutionaries are selected for incompetence).
The upshot is that the share of current senior managers who have anything to contribute to improving public transportation in the US is very low. Not zero, but still very low. The process selects the least imaginative, least technically apt, and least curious people. Whether it’s best practices that do not look outside the Boston-Seattle-San Diego-Miami quadrilateral, or grants that have language that makes it clear foreign knowledge is unwelcome, or hiring practices that exclude immigrants on visas, everything about the process in the US screams it. It’s not a coincidence that the US has the world’s highest construction costs, and when other countries begin to catch up often thanks to adoption of American practices, the US keeps staying ahead.
I was recently asked about the issue of incrementalism in infrastructure, with specific reference to Strong Towns and its position against big projects (e.g. here). It’s useful to discuss this right now in context of calls for a big infrastructure-based federal jobs program in the United States. The fundamental question to answer is, what is the point of incremental projects?
The issue is that the legitimate reason to prefer less ambitious projects is money. If a new subway tunnel costs $5 billion, but you only have the ability to secure $1.5 billion, then you should build what you can for $1.5 billion, which may be a tram rather than a subway, or surface improvements to regional rail instead of a new regional rail tunnel, etc.
A secondary legitimate reason is that even if there is more money, sometimes you get better results out of building something less flashy. This is the electronics-before-concrete approach – in a developed country it’s almost always cheaper to invest in signaling, electrification, and platform upgrades than to build new tunnels. This can look incremental if it’s part of a broader program: for example, if there’s already investment in electrification in the region then extending wires is incremental, so that completing electrification on the commuter rail lines in New York, reopening closed suburban branches in Philadelphia with new wires, and even completing electrification in a mostly-wired country like Belgium and the Netherlands would count.
But the example of electrification in a mostly already electrified place showcases the differences between cost-effectiveness and incrementalism. The same investment – electrification – has a certain cost-effectiveness depending on how much train traffic there is. There’s a second-order effect in that the first line to be electrified incurs the extra cost of two train fleets and the last line has a negative cost in no longer needing two fleets, but this isn’t relevant to first order. Nonetheless, electrifying a system where electrification is already familiar is considered incremental, to the point that there were extensions of electrification in suburban New York in the 1980s and there remain semi-active projects to build more, whereas electrifying one that is currently entirely diesel, like Boston, is locally considered like a once-in-a-generation project.
And that is the real problem. American cities are hardly hotbeds of giant flashy construction. They barely are in highways – big highway construction plans are still done but in suburbs and not anywhere where public transit is even remotely relevant. And transit construction plans are always watered down with a lot of reconstruction and maintenance money; most of the money in the Los Angeles sales tax measures that are sold to the urbanist public as transit measures is not about rail construction, which is why with money programmed through 2060 the region is going to only have one full subway line; an extension of the Red Line on South Vermont is scheduled to open in 2067, partly because construction costs are high but mostly because there are maintenance projects ahead in line.
So in reality, there are two real reasons why incrementalism is so popular in the United States when it comes to transportation, neither of which is legitimate. Both are types of incompetence, but they focus on different aspects of it.
The first reason is incompetence through timidity. Building something new, e.g. rail electrification in Boston or in California, requires picking up new knowledge. The political appointees in charge of transit agencies and the sort of people who state legislators listen to do not care to learn new things, especially when the knowledge base for these things is outside their usual social networks. Can Massachusetts as a state electrify its rail network? Yes. Can it do so cheaply? Also yes. But can the governor’s political appointees do so? Absolutely not, they are incurious and even political people who are not beholden to the governor make excuses for why Massachusetts can’t do what Israel and Norway and New Zealand and Austria and Germany do.
In that sense, incrementalism does not mean prudence. It means doing what has been done before, because the political people are familiar with it. It may not work, but it empowers people who already have political clout rather than sidelining them in favor of politically independent technocrats from foreign countries who might be too successful.
The second reason is incompetence through lack of accountability. This is specific to an approach that a lot of American urbanists have backed, wrongly: fix-it-first, or in its more formal name state of good repair (SOGR). The urbanist emphasis on SOGR has three causes: first, in the 1980s New York had a critical maintenance backlog and neglected expansion in order to fix it, which led to positive outcomes in the 1990s and 2000s; second, in highways, fix-it-first is a good way to argue against future expansion while hiding one’s anti-car ideology behind a veneer of technical prudence; and third, Strong Towns’ specific use case is very small towns with serious issues of infrastructure maintenance costs and not enough residential or commercial demand to pay for them, which it then generalizes to places where there’s more market demand for growth.
In reality, the situation of 1980s’ New York was atypical. Subsequently, the SOGR program turned into a giant money pit, because here was an opportunity to spend enormous sums of capital construction money without ever being accountable to the public in the form of visible expansion. Ask for a new rail line and people will ask why it’s not open – California got egg on its collective face for not being able to build high-speed rail. Ask for SOGR and you’ll be able to brush away criticism by talking about hidden benefits to reliability. Many passengers may notice that trains are getting slower and less reliable but it’s easier in that case to intimidate the public with officious rhetoric that sounds moderate and reasonable.
Incrementalism is fundamentally a method of improving a legitimate institution. The EU needs incremental reform; China needs a democratic revolution. By the same token, in infrastructure, incrementalism should be pushed when, and only when, the status quo with tweaks is superior to the alternatives. (Note that this is not the same as electronics-before-concrete – what Switzerland did with its rail investment in the 1990s was very far-reaching, and had tangible benefits expressed in trip times, timed connections, and train frequency, unlike various American bus redesigns.) Strong Towns does not believe that there’s anything good about the American urban status quo, and yet it, and many urbanists, are so intimidated by things that happened in the 1950s, 60s, and early 70s that they keep pushing status quo and wondering why there is no public transportation outside about eight cities.
I was asked a few months ago about priorities for street pedestrianization in New York. This issue grew in importance during the peak of the corona lockdown, when New Yorkers believed the incorrect theory of subway contagion and asked for more bike and pedestrian support on the street. But it’s now flared again as Mayor de Blasio announced the cancellation of Summer Streets, a program that cordons off a few streets, such a the roads around Grand Central, for pedestrian and bike traffic. Even though the routes are outdoors, the city is canceling them, citing the virus as the reason even though there is very little outdoor infection.
But more broadly, the question of pedestrianization is not about Summer Streets, which is an annual event that happens once and then for the rest of the year the streets revert to car usage. It’s about something bigger, like the permanent Times Square and Herald Square pedestrianization.
In general, pedestrianization of city centers is a good thing. This can be done light, as when cities take lanes off of roadways to expand bike lanes and sidewalks, or heavy, as when an entire street loses car access and becomes exclusive to pedestrians and bikes. The light approach should ideally be done everywhere, to reduce car traffic and make it viable to bike; cycling in New York is more dangerous than in Paris and Berlin (let alone Amsterdam and Copenhagen) since there are too few separated bike lanes and they are not contiguous and since there is heavy car traffic.
The heavy approach should be used when feasible, but short of banning cars cannot be done everywhere. The main obstacle is that in some places a critical mass of consumers access retail by car, so that pedestrianization means drivers will go elsewhere and the region will suffer; this happened with 1970s-era efforts in smaller American cities like Buffalo, and led to skepticism about the Bloomberg-era Times Square pedestrianization until it was completed and showcased success. Of course, Midtown Manhattan is rich in people who access retail by non-auto modes, but it’s not the only such place.
Another potential problem is delivery access. This is in flux, because drone delivery and automation stand to simplify local deliveries, using sidewalk robots at pedestrian scale. If delivery is automated then large trucks no longer offer much benefit (they’re not any faster than a bicycle in a congested city). But under current technology, some delivery access is needed. In cities with alleys the main street can be pedestrianized with bollards while the alleys can be preserved for vehicular access, but New York has about three alleys, which are used in film production more than anything because they connote urban grit.
Taking all of this together, the best places for pedestrianization are,
- City centers and near-center areas. In New York, this is the entirety of Manhattan south of Central Park plus Downtown Brooklyn and Long Island City. There, the car mode share is so low that there is no risk of mass abandonment of destinations that are too hard to reach by car.
- Non-residential areas. The reason is that it’s easier to permit truck deliveries at night if there are no neighbors who would object to the noise.
- Narrow streets with plenty of commerce. They’re not very useful for drivers anyway, because they get congested easily. If there are deliveries, they can be done in off-hours. Of note, traffic calming on wider streets is still useful for reducing pollution and other ills of mass automobile use, but it’s usually better to use light rather than heavy traffic reduction, that is road diets rather than full pedestrianization.
- Streets with easy alternatives for cars, for example if the street spacing is dense. In Manhattan, this means it’s better to pedestrianize streets than avenues.
- Streets that are not useful for buses. Pedestrianized city center streets in Europe are almost never transit malls, and the ones I’m familiar with have trams and not buses, e.g. in Nice.
Taking this all together, some useful examples of where to pedestrianize in New York would be,
- Most of Lower Manhattan. There are no residents, there is heavy commerce, there is very heavy foot traffic at rush hour, and there are enough alternatives that 24/7 pedestrianization is plausible on many streets and nighttime deliveries are on the rest.
- Some of the side streets of Downtown Brooklyn and Long Island City. This is dicier than Manhattan – the mode share in those areas as job centers is far below Manhattan’s. A mid-2000s report I can no longer find claimed 50% for Downtown Brooklyn and 30% for LIC, but I suspect both numbers are up, especially LIC’s; Manhattan’s is 67%, with only 15% car. So there’s some risk, and it’s important to pick streets with easy alternatives. Fulton Mall seems like a success, so presumably expansions can start there and look at good connections.
- St. Mark’s. It’s useless for any through-driving; there’s a bus but its ridership is 1,616 per weekday as of 2018, i.e. a rounding error and a prime candidate for elimination in a bus redesign. There’s so much commerce most buildings have two floors of retail, and the sidewalk gets crowded.
- Certain Midtown side streets with a lot of commerce (that’s most of them) and no buses or buses with trivial ridership (also most of them). One-way streets that have subway stations, like 50th and 53rd, are especially attractive for pedestrianization. Two-way streets, again, are valuable targets for road diets or even transit malls (though probably not in Midtown – the only east-west Manhattan-south-of-59th-Street bus route that screams “turn me into a transit mall” is 14th Street).
The construction costs of rail infrastructure in the Arab world are globally atypical. We looked at the entire region, because of the common use of the literary Arab language; nearly all of this work is due to a New School student named Anan Maalouf, who’s doing long-term work on urban planning as relevant to Nazareth. Here is a presentation he gave at NYU on the subject last month. Update 7/22: here is an updated version of the presentation.
There are identifiable clusters in the Arab world, which is not surprising – it’s similar to how there is a common Nordic cost (which is low), a common cost to the English-speaking world (which is high), and so on. Of course, these clusters are not perfectly predictable ex ante; in light of the most important global pattern with the coronavirus crisis, I keep stressing that there is no distinct Europe vs. East Asia cluster when it comes to costs, and instead both regions have similar averages and huge internal variations. The Arab world does not form an entire cluster itself, but its clusters are at least somewhat understandable based on internal divisions.
One cluster is the six states of the Gulf Cooperation Council: Kuwait, Saudi Arabia, Qatar, Bahrain, the UAE, and Oman. All are distinguished by high incomes, comparable to those of the developed world, but coming almost exclusively from oil extraction. All also have atypically large numbers of immigrants, who form large majorities of the populations of the UAE and Qatar, and who have few rights and earn very low wages by local standards. One might expect that in such an environment, construction costs should be low, since there is ample cheap labor but also money for imported capital. Instead, these states all have high costs; for example, the Doha metro project costs around $700 million per kilometer, and is not even 100% underground but only 90%.
The explanation, per Anan and an Israeli-British planner named Omer Raz, is that there is no interest in cost control in the Gulf region. The GCC states have money. They are buying prestige and the trappings of modernity; for all of their crowing about the superiority of their traditional values and Islamic law, they crave Western acceptance, in similar vein to Singapore. So they invite first-world consultancies to build their infrastructure to build what Aaron Renn would call “world-class in Doha” (or Dubai, or Riyadh, etc.), as opposed to “world-class Doha,” i.e. domestic production that is good enough that other people are attracted to it. On top of it all, Omer gave an example in which Saudi Arabia was not a reliable partner for these foreign consultancies; Anan, too, notes a plethora of postponements and cancellations of rail lines, sometimes because of changing economic conditions, sometimes because these lines are international and relationships between Saudi Arabia and Qatar deteriorated recently, etc.
Another cluster consists of Egypt and Iraq. Both have high costs, in line with other third-world ex-colonies, like India, Vietnam, Indonesia, and Nigeria. The Cairo Metro extensions are $600-700 million per km; the Baghdad Metro is, in PPP terms, $330 million per km for an all-elevated project. This is not surprising – these countries use first-world consultancies with background in high-wage, strong-currency, cheap-capital economies. Unlike in the other datasets, like mine or Yinan Yao’s, Anan included a crucial piece of information: who the lead contractor or consultant was. It’s often a foreign firm, from a much richer country – in Iraq’s case, it’s Alstom. On the other hand, Egypt is using a domestic contractor, Orascom, and costs there remain high.
Finally and most interestingly, there is the Maghreb. One would expect that Tunisia, Algeria, and Morocco should have high costs, just like the other ex-colonies. However, they do not. Anan pointed out that the Arab world inverts my theory about how ex-colonies have higher costs than never-colonized countries like Iran, Turkey, and China. He adds that these countries have much closer ties with France than other ex-colonies do, whether they used to be French outside Africa (i.e. Vietnam) or other European empires’ (e.g. India, Indonesia, Nigeria). Alstom has had continuous presence in the area for 20 years.
In a sense, France didn’t fully decolonize in the Maghreb and the Sahel. It still views these regions as its near abroad, with a forever war in Mali, currency pegs, and deep economic ties with the higher-functioning countries. One can even see the French way of building urban rail in the Maghreb, for example on the Sfax tramway. This isn’t quite every urban subway – the Algiers Metro is pretty expensive. But the Oran Metro has normal costs, and light rail systems like those of Sfax and Casablanca have reasonable costs, as does the TGV system running as Morocco’s high-speed rail system.
So perhaps the issue is that the French planners in the Maghreb are there for long enough that they know the local conditions, and build in accordance with them. In contrast, systems have higher costs if they try to imitate first-world methods either due to first-world consultants’ unfamiliarity with the local situation or due to local cultural cringe.
Normally, the best interstation distance between subway or bus stops does not depend on population density. To resurrect past models, higher overall density means that there are more people near a potential transit stop, but also that there are more people on the train going through it, so overall it doesn’t influence the decision of whether the stop should be included or deleted. Relative density matters, i.e. there should be more stops in areas that along a line have higher density, for example city centers with high commercial density, but absolute density does not. However, there is one exception to the rule that absolute density does not matter, coming from line spacing and transfer placement. This can potentially help explain why Paris has such tight stop spacing on the Métro and why New York has such tight stop spacing on the local subway lines.
Stop spacing and line spacing
The spacing between transit stops interacts with that between transit lines. The reason is that public transportation works as a combined network, which requires every intersection between two lines to have a transfer. This isn’t always achieved in practice, though Paris has just one missed connection on the Métro (not the RER), M5/M14 near Bastille; New York has dozens, possibly as many as all other cities combined, but the lines built before 1930 only have one or two, the 3/L in East New York and maybe the 1/4-5 around South Ferry.
The upshot is that the optimal stop spacing depends on the line spacing. If the line spacing is tight – say this is Midtown Manhattan and there is a subway line underneath Lex/Park, Broadway, 6th, 7th, and 8th – then crossing lines have to have tight stop spacing in order to connect to all of these parallel lines. In the other direction, there were important streetcars on so many important cross-streets that it was desirable to intersect most or ideally all of them with transfers. With so many streetcar lines extending well past Midtown, it is not too surprising that there had to be frequent subway stops.
So why would denser cities have tighter line spacing?
Line spacing and density
The intuitive relationship between line spacing and density is that denser cities need more capacity, which requires them to build more rail lines.
To see this a bit more formally, think of an idealized city on a grid. Let’s say blocks are 100*100 meters, and the planners can figure out the target density in advance when designing the subway network. If the city is very compact, then the subway could even be a grid, at least locally. But now if we expect a low-density city, say 16 houses per block, then the subway grid spacing should be wide, since there isn’t going to be much traffic justifying many lines. As the city densifies, more subway is justifiable: go up to missing middle, which is around 30-40 apartments per block; then to the Old North of Tel Aviv, which would be around 80; then to a mid-rise euroblock, which is maybe 30-40 per floor and 150-200 per block; then finally a high-rise with maybe 500-1,000 apartments.
Each time we go up the density scale, we justify more subway. This isn’t linear – an area that fills 500 apartments per block, which is maybe 100,000 people per km^2, does not get 20 times the investment of an area on the dense side of single-family with 16 houses per block and 5,000 people per km^2. Higher density justifies intensification of service, with bigger and more frequent trains, as well as more crowding. With more subway lines, there are more opportunities for lines to intersect, leading to more frequent stop spacing.
Even if the first subway lines are not planned with big systems in mind, which New York’s wasn’t, the idea of connections to streetcar lines was historically important. A stop every 10 blocks, or 800 meters, was not considered on the local lines in New York early on; however, stops could be every 5 blocks or every 7, depending on the spacing of the major crosstown streets.
Dense blobs and linear density
Line spacing is important to stop spacing not on parallel lines, but crossing lines. If a bunch of lines go north-south close to one another, this by itself says little about the optimal spacing on north-south lines, but enforces tight spacing on east-west lines.
This means that high density encourages tight stop spacing when it is continuous in a two-dimensional area and not just a line. If large tracts of the city are very dense, then this provides justification for building a grid of subway, since the crosstown direction is likely to fill as well; in New York, 125th Street is a good candidate for continuing Second Avenue Subway Phase 2 as a crosstown line for this reason.
In contrast, if dense development follows a linear corridor, then there isn’t much justification for intense crosstown service. If there’s just one radial line, then the issue of line spacing is moot. Even if there are two closely parallel radial lines in the same area, a relatively linear development pattern means there’s no need for crosstown subways, since the two lines are within walking distance of each other. The radial urban and suburban rail networks of Tokyo and Seoul do not have narrow interstations, nor do they have much crosstown suburb-to-suburb service: density is high but follows linear corridors along rapid transit. Dense development in a finger plan does not justify much crosstown service, because there are big low-density gaps, and suburb-to-suburb traffic is usually served efficiently by trips on radial lines with a transfer in city center.
The Modernizing Rail (Un)Conference happened last Sunday. We’re still gathering all the materials, but here are video uploads, including the keynote by Michael Schabas.
We will also have slides as given by presenters who used them. But for now, here are the slides used by the keynote. You may notice that the recording does not begin on the first slide; we missed Schabas’s introduction and some remarks on his background, detailing his 40 years of experience designing public transit systems in a number of countries, mainly Britain and Canada but also elsewhere in the developed world.
My session on construction costs was slide-free (and was not recorded), since I mostly just showed people around our under-construction cost dataset and answered a lot of questions. Some of those questions were annoying, by which I mean they questioned my thinking or brought up a point I haven’t considered before. I am not talking too much about it partly because I was mostly (mostly) repeating things I’ve said here, and the full database should be out later this summer, with all the mistakes I’ve made in currency conversion rates and in not updating for cost overruns fixed.
After my breakout, I was uncertain between which of two sessions to attend – one on HSR-legacy rail compatibility by María Álvarez, and one on equity issues in rail planning, by Grecia White and Ben She. I ended up going to the latter, which featured interesting discussions of inclusion of low-income people and minorities, both as riders (that is, serving people who are not middle-class whites better on regional rail) and as workers (that is, diversifying planning and engineering departments).
It went well in that there was no monopolization of discussion by people who have more a comment than a question, or any open racism or sexism; but it was somewhat frustrating in that while there was a lot of productive discussion of racial equality in rail planning, there was very little of gender equality even though we did intend to talk about both; Grecia was specifically interested in discussing these, for example women’s perceptions of public safety. This is in line with conference demographics – the organizing team and the breakout presenters were each one-third people of color, in line with US demographics; but the organizing team had 2/18 active women and the presenters 3/15. TransitMatters is similar in that regard – racial diversity is comparable to that of the Boston region, and the proportion of regulars who are queer is enormous, but there are very few women.
Finally, I hosted a session on how to set up a transport association, a.k.a. Verkehrsverbund. Christof Spieler did the most talking, and German attendees explained a lot about the difference between a transport association and agency amalgamation. But for the most part that session felt like an ersatz conclusion to the entire conference; it technically lasted an hour, but once the hour had lapsed, people from other sessions came to the room and the conversation continued naturally, talking a bit about different transit planning issues in Germany and a bit about applicability to rail reform in the Northeastern US.