Scooters

Three weeks ago, the consultancy 6t released a study about dockless e-scooters in France. The study is available only in French but there is an executive summary in English. It has convenient demographic profiles of e-scooter riders in Paris, Lyon, and Marseille, and generated some media controversy over the fact that scooters are barely displacing car trips – rather, they’re replacing trips by foot or public transit. This is on top of calls for greater regulations of the mode in multiple countries, not just by NIMBYs but also by serious urbanists like Streestblog’s Angie Schmitt; I was alerted to the study in the first place by Jonathan Rosin, who proposes regulations requiring geofencing to prevent riding on the sidewalk.

And yet, there’s something interesting about scooters and transit in the study, which suggests to me scooters have a positive role to play in a transit city. On p. 80, figure 48 shows combination of scooters with other modes. Out of about 4,000 respondents, 886 say they used scooters in combination with another mode – and of the latter, 66% used it in combination with public transportation.

How worried should we be about rider behavior?

Not really. There is an American discourse concerning dockless transportation that complains about clutter, scooter-pedestrian conflict, and nuisance scooters or bikes left on the sidewalk. The study itself discusses the regulations of e-scooters in various countries. In Britain and Italy e-scooters are legally classified as motor vehicles, which is effectively a ban, and in the US there are onerous regulations such as a requirement for a driver’s license and a minimum age of 18, such as in California. In France, Germany, Switzerland, Austria, Sweden, and Denmark, regulations are laxer, e.g. in Germany the minimum age is 14 and the e-scooter is treated as a bike.

The sort of clutter that Americans complain about was not evident to me in Paris, one of the largest markets in the world for e-scooters as well as bike share (it still has the largest bike share program in the world outside China). As far as I could tell, scooters were mostly used around Nation for recreational trips – at the very least, people did not preferentially leave them right at the Metro and RER station, and I did see a fair number of dockless vehicles (I forget if just bikes or also scooters) at the Bois de Boulogne. Central Paris had a higher density of scooters, but they too did not seem to clutter on the street, and I don’t remember ever having had to dodge a scooter even though people did ride on the sidewalk.

At least at eye level, the lax regulations France does have – the minimum age is 8, cities may choose to permit or prohibit riding on the sidewalk, riding on all streets with speed limit up to 50 km/h is required – appear sufficient. The American, British, and Italian approaches are too draconian and only serve to discourage this mode of transportation.

Gaps in the transit system

Pp. 111-4 have tables describing mode switching. Few of the scooter users would have traveled by car if the scooters hadn’t been available, only 8% including taxis and TNCs (“VTC” in French). In contrast, 46% would have walked and 32% would have taken public transportation.

But is this even a problem? The same tables have the average transit-to-scooter switcher gaining 5 minutes, taking 19 minutes instead of 24. On short trips, scooters are useful for filling little gaps in the regional public transport network. Maybe the origin and destination are not well-connected by Metro, as is for example the case for Nation and much of the Left Bank, so that a transit trip would require transfers. On a poll suggesting non-mutually-exclusive options for why people choose scooters over transit, 68% say it’s nicer, but 44% say it’s faster and 39% say it’s direct. From the perspective of the transit agencies, a mode that makes certain crosstown trips easier without changing trains at Chatelet is a net positive, as it decongests the station as well as other complex transfer points.

According to Owen Gutfreund’s book 20th Century Sprawl, in the 1900s and 1910s the American railroads were supportive of road expansion. To the railroads, cars were a natural complement to trains, extending their range beyond that of a horse or bicycle. Of course, soon the cars turned into competitors, once roads improved to the point of allowing longer-distance travel. But scooters, limited to 25 km/h, do not have that capability. The mode of transportation most comparable to the e-scooter, the bicycle, coexists with a solid regional and intercity rail network in the Netherlands.

Ban cars

The ultimate goal of the green movement in general and of public transit activism in particular should be to ban cars, or else get as close as possible to banning them. Modes of transportation that are not cars that provide alternative functionality to cars are almost always a good idea in this scheme.

Trains are an excellent alternative for long trips, that is out-of-neighborhood trips for such purposes as work, school, citywide social events, and intercity travel. Shorter trips are dominated by walking in transit cities. However, there are two important caveats for the idea of doing short trips on foot. First, there is a genuine in-between region in the 2-4 km range. And second, people with disabilities may not be able to walk long distances, which lowers the upper limit from the 1-2 km range to a much shorter point, perhaps 500 meters – and if their disabilities do not require the use of a wheelchair, then they may well find scooters an acceptable alternative.

In Paris itself, which dominates the survey, scooters are not replacing cars, for a simple reason: few trips in Paris are done by car in the first place. But a robust scooter network can expand out of the city into suburbs with higher present-day car usage, and those suburbs can then become ever more walkable thanks to the displacement of cars by greener modes of travel.

Assume Nordic Costs: London Edition

A month ago I made maps proposing some subway and regional rail extensions in New York and noting what they would cost if New York could build as cheaply as the Scandinavian capitals. Here is the same concept, but with London rather than New York. Here is everything in a single large map:

A full-size (74 MB) map can be viewed here.

Solid lines are existing or under construction, that is Crossrail and the Battersea extension; proposed lines are dashed. Commuter rail lines, that is Thameslink, the soon-to-open Crossrail, and four additional Crossrail tunnels labeled 2 through 5, are always depicted as having separate stations from the other modes, to avoid confusion where one Crossrail station has connections to two adjacent Tube stations (such as Farringdon-Barbican and Moorgate-Liverpool Street). It has many additional interchanges between lines and branches, including some that were left out on purpose, like a Crossrail 1 connection to Oxford Circus, omitted from the under-construction line to discourage riders from using the oversubscribed Victoria line; with four more cross-city lines, the capacity problems would be lessened substantially.

The overall picture is sparser than my New York map. The total projected cost of all of these projects, including some allocated for redoing stations on commuter branches to be given to Tube lines, is £6.8 billion, compared with $37 billion for the New York maps. The reason is that unlike New York, London already has excellent coverage thanks to extensive branching – what it needs is core capacity, which consists of city center tunnels that have high cost per kilometer but need not be long.

There is considerable overbuilding planned in London. Crossrail 2 as depicted on my map is a 6.5 km tunnel between the approach to Victoria Station and the approach to Kings Cross. But as planned, Crossrail 2 extends to a long tunnel parallel to the South West Main Line, a four-track line in a right-of-way that could if truly necessary accommodate six, as well as a long tunnel going north to take over the Lea Valley Lines, which on my map go into Crossrail 5. With gratuitous suburban tunnels and extremely high British construction costs, the budget for Crossrail 2 is around £30 billion, about 20 times what Scandinavia might spend on such a project. Even allowing for the possibility that crossing under three lines at once at Bank is more complex than crossing under two at T-Centralen, this is a difference of a full order of magnitude, counting both total required tunnel length and cost per km.

In addition, there is network simplification. On the Tube this consists of segregating the Northern line’s Bank and Charing Cross branches (already in planning pending the Battersea extension and reconstruction of Camden Town) and through breaking the Circle line into separate Metropolitan and District lines. The latter was estimated by a British blogger to cost £5 billion, based on a rubric in which the Met/District transfer at Aldgate (or Tower Hill) should by itself cost £1 billion; Crossrail and Second Avenue Subway stations cost around half that much, and the more complex T-Centralen and Odenplan stations on Citybanan cost less.

On mainline rail, the service plan is supposed to be deinterlined, as is Transport for London’s long-term goal. The slow tracks of the various mainlines feeding into Central London turn into Crossrail branches, or occasionally Underground extensions, such as Hayes and the Hounslow Loop. The fast tracks stay on the surface to avoid interfering with high-frequency regional metro service. For historic reasons Thameslink mostly stays as-is, with a combination of fast and stopping services, but the curve toward London Bridge should not be used – instead, passengers should have access to Crossrail 3 plus interchanges to the City at London Bridge and a new infill station at Southwark.

London owes it to itself to understand why its construction costs are so high that instead of solving its transport capacity problems with multiple cross-city tunnels in a decade, it’s taking multiple generations to build out such a system. There’s a lot of ongoing discussion about the last-minute delays and cost overruns on Crossrail, but the absolute costs even before the overrun were very high, the highest in the world outside New York City – and Crossrail 2 is set to break that record by a margin.

Teacher Housing and the Rot

I recently saw that San Francisco is considering fast-tracking residential development dedicated to teacher housing. There are quibbles between the moderate mayor and the progressives on city council (“Board of Supervisors”) over the exact structure of the housing subsidies, but both sides agree at least in theory that it should be easier to build housing for teachers; for more background, see article here and Twitter back-and-forth here. I bring this up because it’s an example of bad governance at the local level in the US, one that sends everyone the message, “you should get more clout to bribe politicians.”

The basic problem is that market-rate housing in San Francisco is extremely expensive; in the Mission, a two-bedroom apartment rents for about $5,000 or $5,500 a month. There’s rent control, but it requires one to have lived in the city for a very long time – friends who have lived in the city since the mid-2000s pay around $2,700, which is borderline on a teacher’s salary. Usually the city’s local notables don’t have to care about whether housing is affordable to people in intermediate professions, since our rent is their property values, but “teachers can’t afford housing here” could be a rallying cry for more housing. Thus, they feel like making an exception.

Making an exception is the hallmark of populist governance. In a system with not much rule of law and no trust that there will ever be rule of law, people don’t ask for better rules but to benefit from exceptions. That various exporters threatened to leave Britain over Brexit did not faze Theresa May – every time a company people didn’t hate made such a threat, she offered special subsidies to stay no matter what would happen with the trade agreement with the rump-EU.

The problem with populism is that it sends the message, invest in political marketing and not in productivity. A company that sees that San Francisco is subsidizing housing for teachers in preference to other workers with similar pay and skill level – clerical workers, social workers, lab techs – gets a clear incentive to give its workers more political prestige through political contributions, sponsorships of events the local politicians are interested in, etc. It faces less pressure to invest in its productivity and pay its workers better, since housing is not allocated by market pricing but by political whims.

Under liberal governance, if San Francisco wishes to give its teachers perks, it can pay them better. Programmers get paid $110,000 a year plus benefits (stock options, good health insurance, free food), and the city can if it wants raise taxes and pay teachers similarly; if it can commit to maintaining such high pay indefinitely it can ensure the profession will get more prestige and attract people who otherwise would be writing code for how to sell user data to advertisers slightly more efficiently.

However, a tax hike might fall on the local homeowners and on other rich people who have invested a lot of time and money in obtaining political influence. To avoid burdening the powerful, the city can’t do this – it has to come up with some one-off bespoke deal for teacher housing, rather than permitting more housing across the board and also raising salaries to be competitive with those of the private sector.

Improving the quality of governance requires making it harder for politicians to create such deals. The original YIMBY praxis of state preemption laws is one way to do this: it completely takes local notables out of the loop. While the YIMBY groups on the ground in California don’t go further with this, their favorite state politician, Scott Wiener, who represents San Francisco in the State Senate, is consciously trying to form an informal state party with some ideological coherence based on relevant state issues, led by the question of housing.

It may be prudent to refine this preemption doctrine by interfering with local rules that favor some groups over others in housing. Thus the state should pass a preemption law that forbids dedicated housing for teachers, cops, or other charismatic professions, and requires all housing to be allocated by market pricing, or, failing that, by a clear process of rent control, such as waitlists or income limits. Private actors may continue to buy and sell housing based on their wishes, subject to the usual anti-discrimination law, but municipalities may not use incentives such as subsidies, tax breaks, access to public land, or special fast-tracking of approvals. Such a law may well succeed in the state legislature – unlike the SB 50 process preempting zoning restrictions, this law would not be nakedly offensive to the privileged group of suburban homeowners who managed to scuttle SB 50.

It is not really possible to develop rule of law in an environment in which powerful people can easily circumvent the rules. A city that can offer a way out of an onerous permitting regime to people who make it attractive offers – that is, bribery – has no incentive to make the permitting regime easier, and a powerful incentive to keep it as it is. If building housing becomes easier, politicians lose the ability to extort community benefits by threatening to withhold permits. And if there is a way out for socioeconomic classes that demagogues can’t dismiss as gentrifiers, transients, and rootless cosmopolitans, then politicians gain the ability to threaten everyone else, while employers as well as nonprofits get a powerful message that they should pay more bribes. It’s a win-win for everyone except the hapless residents governed by such corruption.

The question is whether area YIMBYs are willing to leverage the one point of power they do have – namely, their connection to nationwide ideological networks that the local notables of these cities pay lip service to. Out of four New York Times op-ed writers who online liberals like, two (Paul Krugman, Jamelle Bouie) have openly called for more housing in cities, and two (Charles Blow, Michelle Goldberg) have never opined on this issue; NIMBYs have ample local power but little national clout. YIMBYs have this advantage and need to press it to completely sideline machine politics and personality politics – that is, to form a coherent, identifiable political party in California (or New York, or Massachusetts) contesting state and local elections, and if winning local elections without assimilating to the local rot is not possible then work to delegitimize government below the state level as irredeemably corrupt.

Job Centralization in the City

The table below collates job centralization not by CBD as in this post but by central city. Parisian data comes from INSEE, here and here; American data comes from Wikipedia for population and OnTheMap for job counts. In general, I tried making the central city definition about 18% of the metro area to be comparable with Paris, but there is still a lot of variation, so this table should absolutely not be read as a ranking of metro areas by job centralization.

Metro area Population Jobs Central city Central pop’n Central jobs Central job share
Ile-de-France 12,082,144 5,682,048 Paris 2,206,488 1,797,745 31.6%
New York 19,979,477 8,364,410 Manhattan, Brooklyn 4,313,498 2,905,675 34.7%
Los Angeles 13,291,486 5,372,008 Downtown LA to Santa Monica ~1,500,000 1,051,648 19.6%
Chicago 9,498,716 4,142,542 Chicago ex-O’Hare 2,705,994 1,198,562 28.9%
Dallas 7,539,711 3,146,973 Dallas 1,345,047 809,077 25.7%
Houston 6,997,384 2,791,647 Inside 610 + Uptown ~650,000 749,661 26.9%
Washington 6,249,950 2,717,790 District, Arlington, Alexandria 1,100,496 859,751 31.6%
Miami 6,198,782 2,308,048 Miami, Miami Beach 563,221 324,260 14%
Philadelphia 6,096,372 2,570,460 Philadelphia 1,584,138 628,423 24.4%
Atlanta 5,949,951 2,374,233 Fulton County 1,050,114 780,259 32.9%
Boston 4,875,390 2,381,555 Boston, Cambridge 805,234 687,237 28.9%
Bay Area 4,729,484 2,121,580 San Francisco 883,305 642,375 30.3%

The Sunbelt

There appears to be a fair amount of job centralization in the Sunbelt cities, right? In Metro Atlanta, Fulton County has a slightly higher proportion of regional jobs than Paris with a slightly lower share of residential population.

But actually, no. Absolute densities matter in addition to relative centralization of jobs versus residences. In Houston and Los Angeles the central areas are drawn to encircle the downtown and near-downtown job centers – both cities preferentially annex suburban job sites so using municipal boundaries is not useful. A hefty share of area jobs are in these centers, especially in Houston. But ultimately it’s still not a lot of jobs in a very large land area, around 300 square kilometers for both, compared with 100 for the city of Paris or for San Francisco. Fulton County is vast, and the jobs are distributed all over Atlanta and its northern suburbs within the county.

Houston is a particularly good example of monocentrism with a weak center. There are not a lot of strong suburban job centers in Houston – nothing like Silicon Valley, Downtown Newark, the Route 128 corridor, La Defense, Burbank, or Tysons Corner. The city itself has about two thirds of area jobs, thanks to selective annexations. But the share of the CBD in area jobs is low, just 150,000 jobs in the 45/69/10 beltway, or 5.3% of area jobs. Outside the CBD job density plummets, as the outlying job centers making the difference between 5.3% and 26.9% are located at haphazard locations all over 610.

Older American cities

The extent of centralization in the Northeast, Chicago, and San Francisco is greater. New York in particular is a lot like Paris, with about a third of area jobs in a high-density contiguous blob consisting of less than one fifth of regional population. It has nothing like La Defense in the suburbs, but its suburban job centers, while much smaller, include some recognizably dense ones, especially Newark and the Jersey City waterfront. One needs to go well into suburbia to see the difference between Paris, where the suburbs have a structure of density with mid- and high-rise residential development as well as offices next to train stations, and New York, where the job centers in farther-out suburbia, like Central Jersey, have no such structure and are located exclusively based on auto access.

Boston, Washington, and San Francisco all have varying degrees of centralization. I mentioned last year that Boston is increasingly an example of European-style job sprawl, in which jobs spill over from the CBD to nearby areas rather than to faraway office parks. New York has long had such spillover – Long Island City is such a job center, and may at this point have more jobs than Downtown Brooklyn; the Jersey City waterfront is another such example, as is the growth of the Meatpacking District around Google. In Boston the equivalents are Kendall Square and the Seaport; in San Francisco it’s SoMa; in Washington it’s jobs in Arlington around the Orange Line, where older TOD was residential.

Chicago and Philadelphia are the least centralized. Chicago has a well-defined supertall skyline with about 500,000 people working in or near the Loop. But outside that central area, job density craters. Chicago’s share of metro area jobs is about 1.5% higher than its share of metro population, and if we remove the airport, surrounded by suburbia, this difference drops to 0.5%. Philadelphia’s share of metro area jobs is actually lower than its share of metro area population by 1.5%. In these regions, if you’re not working in city center, you’re working at an office park in a middle-class-to-rich suburb built without regard for the area’s vast legacy mainline rail network.

The Private Sector’s Role in Transit Innovation

The United States has long had private success and public failure – not just the sense of private affluence and public squalor, in which household income is high but the state of public services lags, but also in that the private sector is more productive than the public sector. American politicians generally recognize this and often propose programs to use private-sector methods to revitalize the public sector – including infrastructure.

As a rule, existing proposals are failures, such as anything with Elon Musk’s name on it, or when moderate governors like Charlie Baker put some second-rate managers like Luis Ramirez in charge of public transportation agencies. Nonetheless, a program for leveraging private-sector expertise to improve public transportation could be fruitful if politicians aimed at long-term management rather than at favorable short-term press.

Much of what I’m going to propose is an extension of what I blogged last year about the value of outside advice. But here it’s not about domain knowledge, since the American private sector knows little of how to run public transportation well, but rather about more general management principles.

Done is better than good

I encountered the aphorism that done is better than good in the context of video game development. In gamedev, multi-year delays are routine since projects commonly expand in scope or have to adapt to changing circumstances. In the 1990s, Starcraft notoriously was delayed from 1996 to 1998, at a time when one-year development cycles were normal – and then in the 2000s both Starcraft 2 and Duke Nukem Forever took longer than a decade, the latter spending 14 years in development. In such an environment, a culture has to develop that puts an emphasis on finishing something even if some compromises on features are needed.

I genuinely don’t know to what extent other industries use this maxim when projects are delayed. I was told of a metropolitan planning organization (MPO) in which everything gets delayed by months or years as everything has many layers of committee review, and when I asked if the organization had heard of the maxim, my source said “lolno.” I know that TransitMatters can take months to edit a document that I can produce in a day as a blog post, and judging by the delays to FRA reform, originally slated for 2015 but only finalized about a year ago, this is also true of public planning.

Making sure things are done on a timely schedule is critical. This isn’t even about delays in construction so much as about planning and engineering. Managers should learn to cut features when in a crunch, to require teams to prioritize, and to avoid the endless layers of design by committee that lengthen the process without improving results.

State regulations, too, should aim at reducing red tape. American government at all levels uses delays as a substitute for rule of law, with federal and state regulations that require layers of mandatory review. The standard approach for achieving any social purpose is to add yet another layer, even if the delays cause more problems than they solve. For example, there are mandatory reviews of disparate impact lengthening the planning process, even though implementing public transportation improvement faster would have a positive impact on racial minorities as they ride at much higher rates than whites (and not just in the US).

Project management

Project management is an expertise that transfers well between different industries. Thus, a successful private-sector manager can transition to overseeing a complex public infrastructure project. The special aspects of the American public sector, such as high union density, are not that unusual from the perspective of a general-purpose American manager, who may well spend time running companies in traditionally unionized industries.

Boston provides a negative as well as a positive example: the Green Line Extension saw ballooning costs due to poor project management, as the MBTA had no person experienced in the supervision of such a large program of construction. But as soon as the MBTA restarted the project with an outside project manager with ample experience, it managed to cut the headline budget from $3 billion to $2.3 billion; moreover, about half the current cost is sunk from the line’s previous iteration, so going forward the cost is barely $1 billion. This is a very high cost for such a short light rail line, but the factor of three difference with the previous estimate suggests that performing the normal oversight and management could save other expensive American infrastructure projects large sums of money.

Hiring and promotion

There are three types of people: people who have never worked in any large hierarchical company, people who work at human resources, and people who loathe human resources from the bottom of their hearts.

Nonetheless, there are HR departments and there are HR departments. The worst horror stories I have heard about hiring come from the American public sector. They are worse than the worst I have seen in the private sector, like when Hyperloop One assured me they had the visa covered when I asked about it in March 2017 when the Trump administration had just revoked the visa category I was to use, and then when the company wanted to hire me in April it discovered the remaining visa category had a deadline that had passed 2 weeks before. In the public sector, there are positions that remain unfilled for years.

A catalog of problems that afflict hiring at transit agencies in New York and Boston, and presumably in the American public sector in general, includes all of the following:

  1. Onerous checks and long turnaround times. The best applicants will find a private-sector job in 1-2 months while the transit agency takes 6-12 months to go through the process. This affects line positions such as driving a bus as well as office work and managerial positions.
  2. General indifference within HR to applicants. A Boston resident was offered a job at the MTA that required residence within New York City; as the potential hire had a partner who worked in Albany, they proposed that they should live in Poughkeepsie and the MTA hire would commute by Metro-North. HR required them to file forms stating their exact address in Poughkeepsie, never mind that they still needed to find an apartment in the area and had no reason to do so without a written job offer. The applicant was unhired and the position remained unfilled for years.
  3. Periodic hiring freezes instituted by politicians and senior managers who wish to look prudent. Critical departments may remain understaffed, contributing to overstaffing elsewhere through inefficiency, which then provides political justification for keeping the hiring freeze.
  4. Uncompetitive salaries. Starting salaries at planning positions are well below what university graduates with comparable skills can fetch in the private sector. They’re balanced by high pension payouts, but first, the overall level of benefits is very competitive with generic white-collar offices but not with tech with its ample stock options, and second, your typical highly-motivated recent graduate wants a salary now and not a pension in 30 years.
  5. An outdated hiring process. For example, there is no dialogue with how tech companies hire employees, that is the whiteboarding system of technical interviews. The MBTA gave up on this entirely and outsourced its tech to a subsidiary that is shielded away from the rest of the org chart and run as a standard tech company.

The promotion process suffers from some of the same problems. It is outdated, based on the rigid hierarchies of postwar office work, with a tinge of the Japanese salaryman system except without the strict demands the company makes of the employee. A smart 30-year-old will take decades to be in a position to make serious decisions, even if the 55-year-old manager is detached from any new idea from the last generation and is in effect providing no value to the agency.

One additional problem with promotion is known as collision. This is when union agreements based on seniority result in a situation in which promoting an employee would reduce their salary, as they would trade many years of experience at a line position with extra pay for seniority for a higher-level position with no prior experience. The agencies are aware of this problem and have attempted to fix it, and I have heard complaints from union sources, namely Tim Lasker of OPEIU Local 453. I stress that this is the case because it’s common among some reformers on the center and right to blame unions for problems with pension cliffs and collisions, and yet the unions themselves understand that there are problems with both; the real blame should go to management, especially politicians, who refuse to back one-time investments into hiring more people or raising salaries where appropriate.

American business culture

My impression of American business culture is that it is extremely practical and anti-theory. German engineering firms like hiring people with advanced degrees in engineering; at the time of the American bailout of GM and Ford, VW was run by a CEO who had a Ph.D. in engineering and had worked in the auto industry or at suppliers ever since graduating. American firms like hiring people with management experience.

This limits the suitability of the American private sector to public transportation in several ways. The most important is that without theory, American business culture is heavily based on the idea that weak firms just die out and strong firms grow. Turnarounds exist, but a huge fraction of turnaround experts are selling snake oil, and with good connections the snake oil peddlers manage to get appointed to turn around transit agencies. Moreover, because American business culture denigrates foreign best practices, its managers are ill-positioned for an industry where little innovation exists in the US and the most important thing for Americans to do is learn to imitate Europe and East Asia.

The benefits of the private sector are then most pronounced in areas where there is genuine industry-independent management expertise. In those areas, American business absolutely shines; a good rule of thumb to remember is that with completely dysfunctional health care, infrastructure, construction, and education, the US still manages to have labor productivity on a par with the richest European countries and better than anything in Asia, so purely by averaging things out, the rest of the economy must be doing well.

Thus, project management is a core strength in which it is both useful and imperative for the American public sector to learn from private-sector success. The issues of hiring, mentoring, promoting, and firing workers are a core strength as well. Transit agencies have to transition to a model in which jobs are not sinecures, and instead of steep pension cliffs, workers get paid well now and can quit or be let go after a number of years without having to start from zero at their next job.

Finally, the culture of delays must give way to a culture of working quickly, which means knowing when cutting corners is feasible and when it isn’t even at the cost of slowing down the process. Spain achieves low infrastructure construction costs in part by setting its regulations as well as internal oversight and procurement to maximize the speed of decisions: key decisions may be made in a single day, environmental reviews take two months rather than years, and contractors are judged in part by how quickly they can construct a project, on the theory that delays create more opportunities for cost overruns.

None of this is flashy. The most applicable parts of high American private-sector productivity are the most boring. This is less about heroic entrepreneurs, who as a rule have no place in the transportation industry, and more about experienced managers, who as a rule are never written about in the business press unless they’re about to be indicted for embezzlement. Just as the latter have built up a high-performance business culture over the generations, so can they build high-performance state capacity if the politicians let them and give them the resources they need. All it takes is political conscientiousness and more macro- than micromanagement.

Trip Chaining, Redux

There’s been an ongoing conversation about how public transport can be used for non-work trips (and what it means for women) that makes me go back to something I wrote in 2012 about trip chaining. In that post I asserted a distinction between long and short trips, but I didn’t make it very clear. The importance of this distinction is that even though a large majority of trips are not work trips, the sort of urban layout that makes long trips (including work trips) usable by train tends to also make other trips doable on foot.

Trip length and purpose

Mobilität in Deutschland periodically reports on national travel patterns. The 2017 MiD report includes mode shares, trip lengths, and purposes, some broken down by state. Unlike in the Anglosphere or in France, the headline modal share is for all trips, not just work or school trips, and therefore the numbers for public transit look lower and those for walking and cycling look higher.

The important statistic for trip-chaining comes from a table on p. 19. There were 42 million work trips and 41 million shopping trips nationwide in 2017, but the work trips were on average more than three times as long, 16 vs. 5.3 kilometers. The only trip category longer than work was business trips, on average 19 km, including an extensive number of intercity trips, and the only category close to work trips was recreational trips, averaging 15.5 km, also including extensive intercity travel; the median work trip was by a fair margin the longest, 8 km, whereas the median shopping trip was 2 km. Likewise, errand trips were 10.2 km on average with a median of 3.6.

MiD doesn’t break down this data by region, unfortunately. So I can only speculate that if the median trip that people talk about when they talk about trip chaining is 2 km long, then the median trip in the parts of Germany with good public transit is short enough to be done on foot, probably shorter than a kilometer.

Short and long trips

I think it’s useful to collapse the distinction between trips into a binary one: short versus long. Trip length is of course a continuous variable, but a good classification scheme is “can it be done internally to a neighborhood or town?”. If the answer is yes then the trip is short, otherwise it is long.

The commute is an example of a long trip. Commuting to school is usually a long trip as well; even in an environment with school zoning and no selection or choice, a secondary school draws from too large an area to be a single neighborhood except in an extremely large and dense city. Social trips can be long as well – if I go to a gaming convention or a performance in Berlin, or if someone who cares about sports goes to see a football match, it’s a long trip.

Short trips include shopping, errands, eating out, and daycare. The common aspect to them is that they involve common activities with small draws. The supermarket draws from a community of a few thousand, as does the neighborhood restaurant. In contrast, the performance is unique – while many people go to concerts, different people are fans of different artists, so a single band may need to visit a city of millions to fill an auditorium.

Making transit useful for non-work long trips

I bring up the example of going to a sports game as a long trip because American transit agencies deal with that routinely even if they otherwise only care about work trips. Commute trips tend to happen at specific times of day, especially if you’re from the same middle class that transit managers are drawn from. Other long trips have different peaks. Leisure trips tend to happen in the evening and on weekends. Business trips within metropolitan areas tend to happen in the middle of the day during work hours. Trips to the airport depend on time zones – in New York the ones to JFK are concentrated in the afternoon peak, but it’s hard to make generalizations.

Like work trips, non-work long trips are not isotropic – people travel to specific places. A few are as a rule outside city center, such as sports stadiums and airports. Others are within city center to appeal to a wide cross-section of residents, such as event spaces for performances; conventions run the gamut, but richer and more important conventions are likelier to shell out money for city center real estate. Universities may be in or outside city center, depending on the city. Museums are usually city center or in neighborhoods just outside it, such as the Upper East and West Sides in New York or Balboa Park in San Diego.

The length means that the optimal transit network for all non-work trips is largely the same. If trains arrive at a reasonable frequency all day, every day, and form a coherent radial network, then passengers will able to use them for all long trips, even ones that are not for work. The major destinations that are outside city center should whenever possible be junctions between different branches, or get circumferential and not just radial service.

Moreover, there is little point in trying to vary modes for work and non-work trips. Surface transit that averages 15 km/h but saves you a 1-minute trip down to the subway is no more useful for going to a concert than for going to work. If poor urban planning has resulted in an airport that’s nowhere on the rail network or in regional convention centers that are impossible to serve, then buses can fill in the gap, but that’s not optimizing for non-work trips but rather fixing past design mistakes, no different from doing the same when suburban office parks are built far from the train.

The one serious change one needs to make is that the definition of city center needs to be broader than the few square blocks that comprise most American cities’ downtowns. The London Underground’s conception of Central London is not just the City, and likewise cities need to ensure that their West Ends (like, again, San Diego’s Balboa Park) are served as if they were central rather than peripheral areas.

Short trips

It is wrong for cities to try optimizing public transportation for short trips. Most short trips can be done by foot; if they can’t, something is wrong with the city’s urban design. The minimum density required for people to be able to walk to retail is not high – I have a choice of supermarkets within walking distance, and Berlin is not an especially dense city. In Paris, which unlike Berlin is especially dense, I walked to the hypermarket.

Occasionally, when a short trip needs to be done on mechanized transportation, if the city has good transit-oriented commercial development then it is doable by riding the trains a few stops. I recently bought a mattress at Hermannplatz, 3 stops away on U7, longer than most people inside the Ring have to go to such a store, and mattresses are a special case in that dragging them on the streets for a kilometer isn’t fun.

Suppression of auto use is especially valuable for short trips. The reason is that in auto-oriented areas, short as well as long trips are done by car, and if businesses locate based on automobile scale, then only transit can compete – walking and cycling take too long. A hefty proportion of the urban upper middle class prefers to own cars and drive them for short trips, which may induce short trip destinations to locate based on automobile scale even in a walkable city; when I lived in Providence, I walked to the supermarket, but it was located right next to a freeway exit and had ample parking.

Trip chaining

The concept of trip chaining – going directly between destinations in a row rather than just going back and forth between home and a destination – works best with the mode of transportation with the highest frequency and lowest access time: walking. Buying different items at different stores is so ubiquitous that shopping malls were invented specifically to make that experience more pleasant than that of chaining car trips.

Transit cities should not design themselves around trip chaining on transit, destinations for short trips are too difficult to serve. Many cluster on major corridors, but some don’t and stay on residential streets or at street corners. In walkable cities they tend to be fairly isotropic. With short average trips and no discernable centers, the optimal stop spacing on transit is extremely short, to the point of uselessness for all other purposes. If there’s trip chaining, the required frequency is so high that operating costs become unaffordable; a 5-minute wait for a bus may well be unconscionable.

Outside dense cities, suburbs should have a structure of density in which all the plausible destinations are within walking distance of the train station, permitting chaining walking trips with a transit trip. With such structure, the minimum viable density is lower, because buses can connect to the train with a timed transfer and have longer stop spacing as the destinations are all at the town center. In effect, such a structure gives the town center most of the convenience benefits of a shopping mall even without other features such as enclosure and single ownership of the real estate.

Infrastructure is scale-dependent. Public transportation makes this a lot clearer than cars – different modes are used at different scales, and the shape of the network can look visibly different as well. At the scale of short trips, the correct choice of public transportation mode is none – people can and should walk. If the city has generally viable public transit, its urban layout will equally well permit trip chaining on foot. If it doesn’t, then the priority should be to establish a transit city and not to try dragging buses every block.

Overnight Public Transit

American cities try to aim for 24/7 rail service, imitating New York. European cities except Copenhagen do not, and instead have night bus networks. Both of these options have fascinated various transit reformers, but unfortunately sometimes the reformers propose the wrong option for the specific city. This post is intended to be a set of guidelines for night buses and the possibility of 24/7 urban rail.

Maintenance windows

The reason rail service does not run 24/7 is maintenance. Tracks require regular inspections and work, which are done in multi-hour windows. Over the last century or so, the big urban rail systems of the world have standardized on doing this maintenance at night. For example, in Paris there are about 4.5-5 hours every weeknight between the last train of the night and the first train of the morning, and one hour less every weekend night. In Berlin trains run all night on weekends and have 3.5-hour windows of closure on weeknights.

The regular windows may be supplemented by long-term closures, during which passengers are told to use alternatives. Berlin occasionally closes some S-Bahn segments for a few days, and (I believe much more rarely) U-Bahn segments. Paris does so very rarely, usually for an entire summer month during which many Parisians are away on vacation and systemwide ridership is lower, and usually when there are easy alternatives, such as the RER A and Metro Line 1 substituting for each other.

The English-speaking world tends to have extensive weekend shutdowns for maintenance. London has them quite often in addition to nighttime shutdowns. New York runs trains 24/7, using the express tracks on most of its trunk lines to provide service even when the local stations on some segment are closed for maintenance. As American cities have mostly copied New York, they do not know how to wrap up maintenance during their usual nighttime windows and seek weekend closures or shorter hours as well. Thus, for example, BART has claimed that it needs 7-hour windows during weekend nights, citing the example of Paris, whose weekend night closures actually last less than 4 hours.

Flagging

I know of one city that runs its subway 24/7 without interruptions: Copenhagen. Overnight, Copenhagen single-tracks around worksites – frequency is low enough that trains can be scheduled not to conflict. As the trains are driverless, wrong-way running is quite easy. Moreover, there is ample separation between the tracks thanks to the Copenhagen Metro’s twin bore construction; thus, trains do not need to slow down next to worksites, nor must work slow down when a train runs on an adjacent track.

In New York, tracks on each line are right next to each other, with little separation between them. Thus, there are rules that are collectively called flagging under which trains must slow down to a crawl (I believe 10 miles per hour, or 16 km/h) when next to a worksite, while work must pause next to a moving train. The flagging rules apply even when there is more substantial separation between adjacent tracks, such as columns and retaining walls, provided there is any opening allowing passage between the tracks. The safety margins have been made more generous over the last 20 years, which is part of the reasons trains have slowed down, as reported separately by myself, Dan Rivoli, and Aaron Gordon. At the other end, maintenance costs in New York are very high thanks to the constant interruptions.

If it is possible to single-track at night without onerous flagging rules, then cities should go in that direction, using automated rail signaling such as CBTC, even stopping short of driverless trains. In cities with twin-bored tunnels this works provided there are regularly-spaced crossovers between tracks in opposite directions. London is generally poor in such crossovers, and installing new ones may be prohibitively expensive if blasting new connections between tunnels is required. In contrast, on Line 14 in Paris, there are almost sufficient crossovers – the longest stretch is between Bibliotheque and Madelaine, at 14 minutes one-way, and single-direction switches exist at Chatelet and Gare de Lyon, just one of which needs to upgraded to a full diamond crossover. There, 24/7 operation is plausible, though perhaps not so useful as the rest of the system is not 24/7.

Even some cut-and-cover metros can have sufficient separation between tracks for nighttime single-tracking. In Berlin the distance is adequate, at least for some stretches – the tracks are not right next to each other. Even in New York, there are segments where it is feasible to construct partitions between tracks, provided the agency changes flagging rules to permit regular operations and maintenance on adjacent tracks if a partition has been constructed. The cut-and-cover nature of these systems should facilitate this pattern since the cost of building the required crossovers is not prohibitive, just high.

Night buses

Night buses are attractive for a number of reasons. The most important is that in the after hours there is so little surface traffic that buses can match the speed of rapid transit. Moreover, ridership is usually low enough that a bus has adequate capacity. Finally, surface transit can make small detours, for example to reach a common timed transfer, since transit is dependent on both scale and mode. During the day Vancouver has a bus grid, with most buses arriving every 8-10 minutes, but at night it has a half-hourly radial network with a timed transfer, and little relationship with the shape of the SkyTrain network.

Nevertheless, not every city can make appropriate use of night buses. The important factors to consider include the following:

  1. How much does the rapid transit network follow major streets? If it mostly runs on two-way streets, as in Berlin, then running buses that duplicate the metro is easy. But if there are major deviations, especially if there are water crossings involved, then this is harder; in New York, where there are far more crossings of the East River by subway than by road, a night bus network would be virtually useless. Shuttle buses substituting for weekend trackwork are likewise complete failures whenever the subway is more direct than the streets, e.g. the Boston Red Line between Charles-MGH and Park Street.
  2. What is the expected size of the network? A minimum number of lines is required for success, and unless they are very frequent, transfers have to be timed. The half-hourly night buses in Berlin do not work well if untimed, for example.
  3. How long are the routes? This has two aspects. First, very long routes are less competitive with taxis if there are motorways. And second, a half-hourly night bus had better take around an integer number of half-hours minus turnaround time per roundtrip, to avoid wasting service hours. A 25-minute one-way trip is excellent, a 32-minute one a disaster.

Public Transportation and Active Planning

This post is an attempt at explaining the following set of observations concerning government interference and transportation mode choice:

  1. High auto usage tends to involve government subsidies to motorways and other roads
  2. Nonetheless, more obtrusive government planning tends to correlate with more public transport and intercity rail
  3. In places where state planning capacity is weak, transportation evolves in a generally pro-car direction

The main thread tying this all together is that building roads requires a lot of money, but the money does not need to be coordinated. Local districts could pave roads on a low budget and improve incrementally; this is how the US built its road network in the 1910s and 20s, relying predominantly on state and even local planning. In contrast, public transportation requires very good planning. Rapid transit as an infrastructure project is comparable to motorways, with preplanned stopping locations and junctions, and then anything outside dense city cores requires network-wide rail schedule coordination. Good luck doing that with feuding agencies.

I’ve talked a bunch about scale before, and this isn’t exactly about that. Yes, as Adirondacker likes to say in comments, cars are great at getting people to where not a lot of other people want to go. But in cities that don’t make much of an effort to plan transportation, anyone who can get a car will, even for trips to city center, where there are horrific traffic jams. An apter saying is that a developed country is not one where even the poor drive but one where even the rich use public transport.

Right of way and surface transit

The starting point is that on shared right-of-way, cars handily beat any shared vehicle on time. Shared vehicles stop to pick up and drop off passengers, and are just less nimble, especially if they’re full-size buses rather than jitneys. No work needs to be done to ensure that single-occupant vehicles crowd out buses with 20, 40, or even 60 passengers. This happens regardless of the level of investment in roads, which, after all, can be used by buses as well as by cars.

Incremental investment in roads will further help cars more than buses. The reason is that the junctions most likely to be individually grade-separated are the busiest ones, where buses most likely have to stop to pick up and discharge passengers at the side of the road at-grade, whereas cars can go faster using the flyover or duckunder. For example, in New York, the intersection of Fordham Road (carrying the Bx12, currently the city’s busiest bus) and Grand Concourse (carrying the Bx1/2, the city’s sixth and the Bronx’s second busiest route) is grade-separated, but buses have to stop there and therefore cannot have to cross more slowly at-grade.

Within cities, the way out involves giving transit dedicated right of way. This can be done on the surface, but that removes space available for cars. Since cars are faster than public transport in cities that have not yet given transit any priority over private vehicles, they are used by richer people, which means the government needs to be able to tell the local middle class no.

The other option is rapid transit. This can be quite popular it if is seen as modern, which is true in the third world today and was equally true in turn of the century New York. The problem: it’s expensive. The government needs to brandish enough capital at the start for a full line. This is where transit’s scale issue becomes noticeable: while a metro area of 1-2 million will often support a rapid transit line, the cost of a complete line is usually high compared with the ability of the region to pay for it, especially if the state is relatively weak.

The third world’s situation

The bulk of the third world has weak state capacity. Tax revenue is low, perhaps because of political control by wealthy elites, perhaps because of weak ability to monitor the entire economy to ensure compliance with broad taxes.

This does not characterize the entire middle- and low-income world. China has high state capacity, for one, leading to massive visible programs for infrastructure, including the world’s largest high-speed rail network and a slew of huge urban metro networks. In the late 20th century, the four East Asian Tigers all had quite high state capacity (and the democratic institutions of Korea and Taiwan are just fine – the administrative state is not the same as authoritarianism).

In 1999, Paul Barter’s thesis contrasted the transit-oriented character of Tokyo, Seoul, Hong Kong, and Singapore, with the auto-oriented character of Bangkok and Kuala Lumpur, and predicted that Manila, Jakarta, and Surabaya would evolve more like the latter set of cities. Twenty years later, Jakarta finally opened its first metro line, and while it does have a sizable regional rail network, it is severely underbuilt for its size and wealth, which are broadly comparable to the largest Chinese megacities. Manila has a very small metro network, and thanks to extremely high construction costs, its progress in adding more lines is sluggish.

Kuala Lumpur and Bangkok both have very visible auto-centric infrastructure. Malaysia encouraged auto-centric development in order to stimulate its state-owned automakers, and Thailand has kept building ever bigger freeways, some double-deck. More to the point, Thailand has not been able to restrain car use the way China has, nor has it been able to mobilize resources to build a large metro system for Bangkok. However, Indonesia and the Philippines are not Thailand – Jakarta appears to have a smaller freeway network than Bangkok despite being larger, and Manila’s key radial roads are mostly not full freeways but fast arterials.

Planning capacity

Public transportation and roads both form networks. However, the network effects are more important for transit, for any number of reasons:

  1. Public transportation works better at large scale than small scale, which means that urban transit networks need to preplan connections between different lines to leverage network effects. Freeway networks can keep the circumferential highways at-grade because at least initially they are less likely to be congested, and then built up gradually.
  2. Public transportation requires some integration of infrastructure, service, and rolling stock, and this is especially true when the national rail network is involved rather than an urban subway without any track connections to the mainline network.
  3. The biggest advantage of trains over cars is that they use land more efficiently, and this is more important in places with higher land prices and stronger property rights protections. This is especially true when junctions are involved – building transfers between trains does not involve condemning large tracts of land, but building a freeway interchange does.

None of this implies that cars are somehow smaller-government than trains. However, building a transportation network around them does not require as competent a planning department. If decisions are outsourced to local notables who the state empowers to act as kings of little hills in exchange for political support, then cobbling together a road network is not difficult. It helps those local notables too, as they get to show off their expensive cars and chauffeurs.

Trains are more efficient and cleaner than cars, but building them requires a more actively planned infrastructure network. Even if the total public outlay is comparable, some competent organ needs to decide how much to appropriate for which purpose and coordinate different lines – and this organ should ideally be insulated from the corruption typical of the average developing country.

Bronx Bus Redesign

New York is engaging in the process of redesigning its urban bus network borough by borough. The first borough is the Bronx, with an in-house redesign; Queens is ongoing, to be followed by Brooklyn, both outsourced to firms that have already done business with the MTA. The Bronx redesign draft is just out, and it has a lot of good and a great deal of bad.

What does the redesign include?

Like my and Eric Goldwyn’s proposal for Brooklyn, the Bronx redesign is not just a redrawing of lines on a map, but also operational treatments to speed up the buses. New York City Transit recognizes that the buses are slow, and is proposing a program for installing bus lanes on the major streets in the Bronx (p. 13). Plans for all-door boarding are already in motion, to be rolled out after the OMNY tap card is fully operational; this is incompetent, as all-door boarding can be implemented with paper tickets, but at this stage this is a delay of just a few years, probably about 4 years from now.

But the core of the document is the network redesign, explained route by route. The map is available on p. 14; I’d embed it, but due to file format issues I cannot render it as a large .png file, so you will have to look yourselves.

The shape of the network in the core of the Bronx – that is, the South Bronx – seems reasonable. I have just one major complaint: the Bx3 and Bx13 keep running on University Avenue and Ogden Avenue respectively and do not interline, but rather divert west along Washington Bridge to Washington Heights. For all of the strong communal ties between University Heights and Washington Heights, this service can be handled with a high-frequency transfer at the foot of the bridge, which has other east-west buses interlining on it. The subway transfer offered at the Washington Heights end is low-quality, consisting of just the 1 train at the GWB bus station; a University-Ogden route could instead offer people in University Heights a transfer to faster subway lines at Yankee Stadium.

Outside the South Bronx, things are murkier. This is not a damn by faint praise: this is an acknowledgement that, while the core of the Bronx has a straightforward redesign since the arterials form a grid, the margins of the Bronx are more complicated. Overall the redesign seems fairly conservative – Riverdale, Wakefield, and Clasons Point seem unchanged, and only the eastern margin, from Coop City down to Throgs Neck, sees big changes.

The issue of speed

Unfortunately, the biggest speed improvement for buses, stop consolidation, is barely pursued. Here is the draft’s take on stop consolidation:

The spacing of bus stops along a route is an important factor in providing faster and more reliable bus service. Every bus stop is a trade-off between convenience of access to the bus and the speed and reliability of service. New York City buses spend 27 percent of their time crawling or stopped with their doors open and have the shortest average stop distance (805 feet/245 m) of any major city. London, which has the second closest stop spacing of peer cities, has an average distance between stops of 1,000 ft/300 m.

Bus stop spacing for local Bronx routes averages approximately 882 feet/269 meters. This is slightly higher than the New York City average, but still very close together. Close stop spacing directly contributes to slow buses and longer travel times for customers. When a bus stops more frequently along a route, exiting, stopping, and re-entering the flow of traffic, it loses speed, increases the chance of being stopped at a red traffic signal, and adversely affects customers’ travel time. By removing closely-spaced and under-utilized stops throughout the Bronx, we will reduce dwell time by allowing buses to keep moving with the flow of traffic and get customers where they need to go faster.

Based on what I have modeled as well as what I’ve seen in the literature, the optimal bus stop spacing for the Bronx, as in Brooklyn, is around 400-500 meters. However, the route-by-route descriptions reveal very little stop consolidation. For example, on the Bx1 locals, 3 out of 93 stops are to be removed, and on the Bx2, 4 out of 99 stops are to be removed.

With so little stop consolidation, NYCT plans to retain the distinction between local and limited buses, which reduces frequency to either service pattern. The Bx1 and Bx2 run mostly along the same alignment on Grand Concourse, with some branching at the ends. In the midday off-peak, the Bx1 runs limited every 10 minutes, with some 12-minute gaps, and the Bx2 runs local every 9-10 minutes; this isn’t very frequent given how short the typical NYCT bus trip is, and were NYCT to eliminate the local/limited distinction, the two routes could be consolidated to a single bus running every 4-5 minutes all day.

How much frequency is there, anyway?

The draft document says that consolidating routes will allow higher frequency. Unfortunately, it makes it difficult to figure out what higher frequency means. There is a table on p. 17 listing which routes get higher frequency, but no indication of what the frequency is – the reader is expected to look at it route by route. As a service to frustrated New Yorkers, here is a single table with all listed frequencies, weekday midday. All figures are in minutes.

Route Headway today Proposed headway
Bx1 10 10
Bx2 9 9
Bx3 8 8
Bx4/4A 10 8
Bx5 10 10
Bx6 local 12 8
Bx6 SBS 12 12
Bx7 10 10
Bx8 12 12
Bx9 8 8
Bx10 10 10
Bx11 10 8
Bx12 local 12 12
Bx12 SBS 6 6
Bx13 10 8
Bx15 local 12 12
Bx15 limited 10 10
Bx16 15 15
Bx17 12 12
Bx18 30 20
Bx19 9 9
Bx20 Peak-only Peak-only
Bx21 10 10
Bx22 12 8
Bx23 30 8
Bx24 30 30
Bx26 15 15
Bx27 12 12
Bx28 17 8
Bx38 (28 variant) 17 discontinued
Bx29 30 30
Bx30 15 15
Bx31 12 12
Bx32 15 15
Bx33 20 20
Bx34 20 20
Bx35 7 7
Bx36 10 10
Bx39 12 12
Bx40 20 8
Bx42 (40 variant) 20 cut to a shuttle, 15
Bx41 local 15 15
Bx41 SBS 10 8
Bx46 30 30

A few cases of improving frequency on a trunk are notable, namely on the Bx28/38 and Bx40/42 pairs, but other problem spots remain, led by the Bx1/2 and the local and limited variants on some routes.

The principle of interchange

A transfer-based bus network can mean one of two things. The first, the one usually sold to the public during route redesigns, is a grid of strong routes. This is Nova Xarxa in Barcelona, as well as the core of this draft. Eric’s and my proposal for Brooklyn consists entirely of such a grid, as Brooklyn simply does not have low-density tails like the Bronx, its southern margin having high population density all the way to the boardwalk.

But then there is the second meaning, deployed on networks where trunk routes split into branches. In this formulation, instead of through-service from the branches to the trunk, the branches should be reduced to shuttles with forced transfers to the trunk. Jarrett Walker’s redesign in Dublin, currently frozen due to political opposition (update: Jarrett explains that no, it’s not really frozen, it’s in revision after public comments), has this characteristic. Here’s a schematic:

The second meaning of the principle of interchange is dicey. In some cases, it is unavoidable – on trains, in particular, it is possible to design timed cross-platform transfers, and sometimes it’s just not worth it to deal with complex junctions or run diesels under the catenary. On buses, there is some room for this principle, but less than on trains, as a bus is a bus, with no division into different train lengths or diesels vs. electrics. Fundamentally, if it’s feasible to time the transfers at the junctions, then it’s equally possible to dispatch branches of a single route to arrive regularly.

New York’s bus network is already replete with the first kind of interchange, and then the question is where to add more of it on the margins. But the Bronx draft includes some of the second, justified on the grounds of breaking long routes to improve reliability. Thus, for example, there is a proposed 125th Street crosstown route called the M125, which breaks apart the Bx15 and M100. Well, the Bx15 is a 10.7 km route, and the M100 is an 11.7 km route. The Bx15 limited takes 1:15-1:30 end to end, and the M100 takes about 1:30; besides the fact that NYCT should be pushing speedup treatments to cut both figures well below an hour, if routes of this length are unreliable, the agency has some fundamental problems that network redesign won’t fix.

In the East Bronx, the same principle of interchange involves isolating a few low-frequency coverage routes, like the Bx24 and Bx29, and then making passengers from them transfer to the rest of the network. The problem is that transferring is less convenient on less frequent buses than on more frequent ones. The principle of interchange only works at very high frequency – every 8 minutes is not the maximum frequency for this but the minimum, and every 4-6 minutes is better. It would be better to cobble together routes to Country Club and other low-density neighborhoods that can act as tails for other trunk lines or at least run to a transfer point every 6-8 minutes.

Is any of this salvageable?

The answer is yes. The South Bronx grid is largely good. The disentanglement of the Bx36 and Bx40 is particularly commendable: today the two routes zigzag and cross each other twice, whereas under any redesign, they should turn into two parallel lines, one on Tremont and one on 180th and Burnside.

But outside the core grid, the draft is showing deep problems. My semi-informed understanding is that there has been political pressure not to cut too many stops; moreover, there is no guarantee that the plans for bus lanes on the major corridors will come to fruition, and I don’t think the redesign’s service hours budget takes this into account. Without the extra speed provided by stop consolidation or bus lanes, there is not much room to increase frequency to levels that make transfers attractive.

Assume Nordic Costs

I wrote a post last year proposing some more subway lines for New York, provided the region could bring down construction costs. The year before, I talked about regional rail. Here are touched-up maps, with costs based on Nordic levels. To avoid cluttering the map in Manhattan, I’m showing subway and regional rail lines separately.

A full-size 52 MB version of the subway map can be found here and a 52 MB version of the regional rail map can be found here.

Subways are set at $110 million per km underground, outside the Manhattan core; in more difficult areas, including underwater they go up to $200-300 million per km, in line with Stockholm Citybanan. Lacking data for els, I set them at $50 million per km, in line with normal subway : el cost ratios. The within-right-of-way parts of Triboro are still set at $20 million per km (errata 5/30: 32 out of 35 km are in a right-of-way and 3 are in a new subway, despite what the map text says, but the costs are still correct).

Overall, the subway map costs $22 billion, and the regional rail one $15 billion, about half as high as the figure I usually quote when asked, which is based on global averages. This excludes the $2 billion for separated intercity rail tracks, which benefit from having no stations save Penn (by the same token, putting the express rather than local lines in the tunnel is a potential cost saving for Crossrail 2). It also excludes small surface projects, such as double-tracking the Northern Branch and West Shore Line, a total of 25 and 30 km respectively, which should be $300-550 million in total, and some junction fixes. There may also be additional infill stations on commuter rail, e.g. at intersection points with new subway extensions; I do not have Nordic costs for them, but in Madrid they cost €9 million each.

The low cost led me to include some lines I would not include elsewhere, and decide marginal cases in favor of subways rather than els. There is probably no need for the tunnel connecting the local tracks of Eighth Avenue and Fulton Street Lines, but at just $1.2 billion, it may be worth it. The line on Northern Boulevard and the Erie Main Line should probably be elevated or in a private right of way the entire way between the Palisades and Paterson, but at an incremental cost of $60 million per km, putting the Secaucus and East Rutherford segments underground can be justified.

In fact, the low cost may justify even further lines into lower-density areas. One or two additional regional rail tunnels may be cost-effective at $300 million per kilometer, separating out branches like Port Washington and Raritan Valley and heading to the airports via new connections. A subway line taking over lanes from the Long Island Expressway may be useful, as might another north-south Manhattan trunk feeding University Avenue (or possibly Third Avenue) in the Bronx and separating out two of the Brighton Line tracks. Even at average costs these lines are absurd unless cars are banned or zoning is abolished, but at low costs they become more interesting.

The Nordic capitals all have extensive urban rail networks for their sizes. So does Madrid: Madrid and Berlin are similar in size and density, but Berlin has 151 km of U-Bahn whereas Madrid has 293 km of metro, and Madrid opened a second Cercanías tunnel in 2008 for around $100 million per km and is planning a third tunnel for next decade (source, PDF-pp. 104-108). Things that are completely ridiculous at American costs – say, any future subway expansion – become more reasonable at average costs; things that are completely ridiculous at average costs likewise become more reasonable at Nordic or Spanish costs.