This is somewhat of an addendum to my post before about dispersal of urban networks toward cheaper cities. I addressed the question of dispersal from rich, expensive metro areas, especially San Francisco, to cheaper ones, as a way of dealing with high housing prices. But more common is dispersal within metro areas: gentrification spilling from a rebounding neighborhood to adjacent neighborhoods that remain cheaper, and office space spilling from the primary CBD to the edge cities. I am going to address the latter issue in this post.
CBDs are expensive. They have intense demand for office space, as well as high-end retail and hotels. In many cities, there’s demand for office space even at the construction costs of supertall skyscrapers, going up to about $5,000-6,000 per square meter in privately-built New York towers. Zoning regimes resist the height required to accommodate everyone, and this is worse in Europe than in North America and high-income East Asia. Paris proper has many towers just above the 100 meter mark, but only three above 120. On a list of the tallest buildings in Sweden, not a single one above 100 meters is in central Stockholm, and the tallest within the zone are not in the CBD but in Södermalm; compare this with Vancouver, a metro area of similar size. But in the US, too, expanding CBDs is difficult in the face of neighborhood opposition, even in Manhattan.
The solution many cities have adopted is to put the skyscrapers in edge cities. Paris famously built La Defense, which has far more skyscrapers than the city proper does; Stockholm is building skyscrapers in Kista; London built Canary Wharf; Washington, the major US city with the tightest CBD height limits, sprouted skyscraper clusters in several suburbs in Maryland and Virginia. Ryan Avent proposed this as one solution to NIMBYism: in new-build areas, there are few residents who could oppose the new development. In contrast, near zoning-constrained CBDs, not only are there many residents, but also the land is so desirable that they are typically high-income, which means they have the most political power to oppose new development.
The problem with this solution is that those secondary CBDs are not public transit hubs. In Paris, this has created an east-west disparity, in which people from (typically wealthy) western suburbs can easily reach La Defense, whereas people from poorer ones need to take long RER trips and often make multiple transfers. In every transit city, the CBD is unique in that it can be reached from anywhere. To give similar accessibility to a secondary center, massive investment is required; Paris is spending tens of billions of euros on circumferential regional rail lines to improve suburb-to-suburb connectivity, expand access in the eastern suburbs, and ameliorate the east-west imbalance (see for example isochrones on PDF-pp. 20-21 of the links here). Those lines are going to be well-patronized: the estimate is 2 million daily passengers. And yet, the east-west imbalance, if nothing else, would be a lesser problem if instead of building La Defense, Paris had built up Les Halles.
The situation in other cities is similar. Kista is on one branch of one subway line, two stops away from its outer terminus. Living in Central Stockholm, my coworkers and I can get to KTH on foot or by bike, but a coworker who teaches at KTH’s satellite campus in Kista has a long commute involving circumferential buses (taking the subway and changing at T-Central would be even longer because of the detour). While many individual sub-neighborhoods of Central Stockholm are quite dense, the overall density in the center is not particularly high, certainly not by the standards of Paris or New York. A similar problem happens in Washington, where the biggest edge city cluster, Tysons Corner, is traditionally auto-oriented and was only just connected to Metro, on a branch. This always affects poorer people the worst, as they can’t afford to live in the CBD, where there is easy access to all secondary destination, and often are pushed to suburbs with long commutes.
There is a political economy problem here, as is usually the case with zoning. (Although in the largest cities skyscraper heights are pushing beyond the point of constant marginal costs, purchase prices at least in New York are much higher than construction costs.) The people living near CBDs, as noted before, are usually rich. The displacement of office space to the suburbs affects them the least, for three reasons. First, if they desire work within walking distance or short subway distance, they can have it, since their firms typically make enough money to afford CBD office rents. Second, since they live in the transit hub, they can access suburban jobs in any direction. And third, if the transit options are lacking, they can afford cars, although of course traffic and parking remain problematic. Against their lack of incentive to support CBD office space, they have reasons to support the status quo: the high rents keep it exclusive and push poor people away, and often the traditional mid-rise buildings are genuinely more aesthetic than skyscrapers, especially ones built in modernist style.
These concerns are somewhat muted in the US, where rich people decamped for the suburbs throughout the 20th century, and have supported zoning that mandates single-family housing in the suburbs, instead of staying in the city and supporting zoning that keeps the city mid-rise. This may have a lot to do with the formation of high-rise downtowns in American cities of such size that in Europe they’d be essentially skyscraper-free.
However, what’s worse in the US is the possibility of short car-free commutes to the edge cities. Where La Defense is flanked by suburbs with high residential density, and Kista’s office blocks are adjacent to medium-density housing projects for working- and middle-class people, American edge cities are usually surrounded by low-density sprawl, where they are easily accessible by car but not by any other mode of transportation. This is because the American edge cities were usually not planned to be this way, but instead arose from intersections of freeways, and developed only after the residential suburbs did. As those edge cities are usually in rich areas, the residents again successfully resist new development; this is the point made in Edgeless Cities, which notes that, in major US metro areas, growth has been less in recognizable edge cities and more in lower-density edgeless cities.
As with the possibility of dispersing innovation clusters from rich, expensive metro areas to poorer and cheaper ones, the already-occurring dispersal from city centers to edge and subsequently edgeless cities has negative effects. It lengthens transit commutes. Although in Tokyo, long commutes first arose as a problem of a monocentric CBD, and the city developed secondary CBDs as a solution, the situation in European cities an order of magnitude smaller is very different. It worsens housing segregation: the development of an edge city tends to be in the direction of the favored quarter, since that’s where the senior managers live, and conversely, higher-income workers can choose to move nearby for the short commute. Although nearly all metro areas have favored quarters, decentralization of jobs thus tends to lengthen the commutes of poor people more than those of rich people.
This is not quite the same as what happens when entire metro areas are forced to disperse due to housing cost. The agglomerations generally stay intact, since an entire industry can move in the same direction: smaller cities have just one major favored quarter with edge cities, and larger ones still only have a few, so that industries can specialize, for example in New York, biotech and health care cluster in the Edison-Woodbridge-New Brunswick edge city. Moreover, the specialized workers are usually high-income enough that they can stay in the central city or migrate to the favored quarter. San Francisco’s programmers are not forced to move individually to faraway poor neighborhoods; they move in larger numbers to ones near already gentrifying ones, spurring a new wave of gentrification in the process; were they to move alone, they’d lose the access to the tech shuttles. The negative effects are predominantly not on richer people, but on poorer people.
The problem is that even among the poor, there is little short-term benefit from supporting upzoning. If Paris, London, and Stockholm liberalize housing and office construction, the first towers built of both kinds will be luxury, because of the large backlogs of people who would like to move in and are willing to pay far in excess of construction costs. I am going to develop this point further in two posts, on what is best called NITBYism – Not In Their Backyard – but this means that the incentive for poor and peripheral populations is not to care too much about development in rich centers. The marginal additional building in a rich city center is going to go to the upper middle class; sufficient construction would trickle to the middle class; only extensive construction would serve the working class, and then not all of it.
In the US, the marginal additional building may actually displace poor people, if no new construction is allowed, simply by removing low-income apartments. It may even create local demand for high-income housing, for example by signaling that the neighborhood has improved. In San Francisco, this is compounded by the tech shuttles, as a critical mass of Silicon Valley-bound residents can justify running shuttles, creating demand for more high-income housing.
The amount of construction required to benefit the bottom half of the national income distribution is likely to be massive. This is especially true in France and the UK, which have sharp income differences between the capital and the rest of the country; their backlogs of people who would like to move to the capital are likely in the millions, possibly the high millions. Such massive construction is beyond the pale of political reality: the current high-income resident population is simply not going to allow it – when forced to share a building with the working class, it pushes for poor doors, so why would it want zoning that would reduce the market-rate rent to what the working class would afford? The only political possibility in the short run is partial plans, but these are not going to be of partial use to the working class, but of no use to it, benefiting the middle class instead. As a result, there is no push by the working class and its social democratic political organs to liberalize construction, nor by the small-is-beautiful green movement.
Ultimately, the attempt to bypass restrictions on urban CBD formation by building edge cities, like every other kludge, is doomed to failure. The fundamental problem of rich people making it illegal to build housing nearby is not solved, and is often made even worse. The commutes get worse, and the inequality in commutes between the rich and the poor grows. Office space gets built, where otherwise it would spread along a larger share of the medium-rise CBD, but for most workers, this is not an improvement, and the environmental effects of more driving have negative consequences globally. And once city center is abandoned to the rich, there is no significant political force that can rectify the situation. What seems like a workaround and an acceptable compromise only makes the situation worse.
Freeways are, in principle, much safer than roads with at-grade crossings. With postwar design standards, they eliminate the frictions that are responsible to a vast majority of accidents: grade crossings, left turns, opposite traffic (since they have medians by design), and so on. They also maintain higher design speeds and capacity than less safe local streets. But a more interesting question for policy purposes than “are freeways safer?” is “does the construction of freeways increase road safety?”
For some evidence that the answer is no, see PDF-page 3 of a John Adams paper from 1987 arguing for the continued primacy of Smeed’s Law. Traffic deaths per unit of vehicle distance driven had declined in both the US and UK at a rate following a multi-decade log-linear trend: 3.3% per year in the US, 4.7% in the UK. Regardless of whether Adams’ theory is correct, we can compare actual death rates to the trendline to see what happened. In the US, where the data goes farther back, the greatest period of freeway construction started in the mid-1950s and ended in about 1970; this was also a period in which traffic deaths increased, even more than the trendline based on the explosive growth in driving predicts. Of course the Interstate system also led to traffic growth on at-grade arterials, but the greatest construction growth was in freeways, and on top of this suburban sprawl meant more people would be driving on both the new freeways and the older parkways.
The Smeed’s Law explanation of this is as follows: drivers compensate for the greater safety of freeways by driving more carelessly, on both the freeways and the connecting local roads. The freeways are still safer, but the presence of any safety-improving technology will translate entirely to higher speed and capacity (i.e. drivers keep less distance than they would otherwise), and more careless driving.
There may be other explanations out there – for example, the construction of more roads will cause more dangerous vehicles to start circulating that would not otherwise. These include heavy trucks, and also cars piloted by poor drivers who would not have driven if the construction of an expansive highway had redirected development in such a way that more driving would be needed.
But in either case, what this means is that even though a freeway upgrade of a notoriously unsafe road will make it safer, it will not make the overall road network safer. To argue by analogy with congestion pricing, it is possible that the only way to bend the curve and accelerate the downward trend of vehicle deaths, beyond reducing driving, is to make it more expensive to drive unsafely. For example, insurance requirements could be raised from $25,000 to the rough insurance value of human life in the US, which is in the millions. (The same should be true of any transportation system, but buses and trains are much safer for their passengers than cars.)
The urban geography of transit cities and of car cities is relatively well-understood. In a transit city, there will be a strong CBD surrounded by residences with spiky secondary centers, all quite small geographically but dense, centered around train stations and junctions; because density is high throughout, minor trips are done on foot. In a car city, all trips are done by car, the core is weak, and most employment is in suburban edge cities and edgeless cities.
What I haven’t seen is an explanation of how urban geography works in mixed metro areas: there are those in which short trips are done on foot and long ones in cars, such as new urbanist developments, and those in which short trips are done by car and long ones on transit, such as park-and-ride-oriented commuter suburbs. It is the latter that I want to address in this post.
The first feature of park-and-rides is that of all combinations of modes of transportation, they are the fastest and enable suburbs to sprout the farthest from the center. This is because the segment of the trip done in a car is uncongested and so driving is faster than transit, while the segment done on a train parallels a congested road, and conversely makes few stops so that average speeds are high.
On top of this, because intra-suburban trips are done by car, the density in the suburbs is very low, comparable to proper car cities (see the lower end of the density profiles of the New York, Chicago, and Boston metro areas), and this forces sprawl to go outward. New York is the world’s most sprawling city measured in total built-up area; the only other city of comparable size that’s not a transit city or a bus/jitney city is Los Angeles, which is forced to have denser suburbs because of the mountains. Of course Houston and Dallas sprawl even more relative to size, but because they lack New York’s transit-oriented core, there’s an inherent limit to their size.
The other feature is that there’s a definite socioeconomic history to the development of the auto-oriented commuter suburbs of transit cities. First, people move to the suburbs and commute into the city, almost always by train due to road congestion (or, as in the earliest New York suburbs, because mass motorization hasn’t arrived yet). The mass exodus into these suburbs comes from cars rather than commuter rail, and so the local services for people living in those suburbs are built at automobile scale, rather than at the walkable town center scale of 1910.
In North America there’s also a definite class element here – the early movers are the rich rather than the poor. Historically this was partly because poor people couldn’t afford regular train fare, and partly because the impetus for suburbanization was idyllic country homes with access to urban jobs rather than cheap housing for the poor. If I’m not mistaken, this wasn’t the case in Australian cities’ suburbanization, leading to a more urban transit-style mode of running mainline rail. The result of this class distinction is that North American commuter rail styles itself as for the rich: agencies make an effort to ensure everyone has a seat and downplay comfortable standing space, and the expectation is that transit is a last-ditch mode of transportation for when cars just don’t have the capacity to get people downtown, and so nobody needs to take the trains in the off-peak or take a bus to the train.
The result is that the park-and-ride city will still have a strong core with high-capacity transportation, and the primary CBD will maintain its supremacy for high-income jobs. Establishing edge cities in the direction of the favored quarter can happen, but there’s still a congested city nearby, and so from many directions it’s impossible to drive, and taking transit is impossible. Thus jobs in White Plains and Stamford are not nearly as high-paying as jobs in Manhattan.
There can even be secondary CBDs, if the inner part of the metro area, where people take transit more regularly than the suburban commuters do, is large enough. But those secondary CBDs are frequently quite auto-oriented. Brooklyn’s mode share for jobs is only 42-39 in favor of transit (for residents, it’s 60-25), and all other counties in the New York region except Manhattan have more workers driving than taking transit, a situation that is not true if one looks at residents. Those secondary CBDs then have mixed characteristics: they are dense and fairly walkable, as can be expected based on their history and location, but also have plentiful parking and a large share of drivers demanding even more. They can accommodate multiple modes of transportation, but driving is more convenient, and from the suburbs the commuter rail system isn’t always geared to serve them.
One third of the MBTA’s outstanding debt, about $1.7 billion, comes from transit projects built by the state as part of a court-imposed mitigation for extra Big Dig traffic; interest on this debt is about two-thirds the agency’s total present deficit. Metra was prepared to pay for a project to rebuild rail bridges that would increase clearance below for trucks and cut the right-of-way’s width from three to two tracks. Rhode Island is spending $336 million on extending the Providence Line to Wickford Junction, with most of the money going toward building parking garages at the two new stations; Wickford Junction, in a county whose number of Boston-bound commuters is 170, is getting 1,200 parking spaces.
Supporters of transportation alternatives talk about the inequity between highway and transit funding in the US, but what they’re missing is that the transit funding bucket includes a lot of things that are manifestly not about transit. At their best, they are parking lots and other development schemes adjacent to train stations, which would’ve been cheap by themselves. At their worst, they are straight highway projects, benefiting road users only.
The situation in Boston, while unique in its brazenness, is not unique in concept. In the US, where there are no pollution taxes on fuel, the only way to mitigate air pollution is by regulation and by building alternatives simultaneously. Put another way, combined highway and transit construction is in most cases not really a combined project; it’s a highway project, plus required mitigation. Requiring the transit agency to shoulder the debt and the operating subsidies is exactly requiring transit users to pay for highways. It’s equivalent to charging transit multiple dollars per gallon of gas saved from any mode shift. And it may get even worse: the proposed House transportation bill includes a provision to allow spending national air pollution control funds on regular highway widening, in addition to the current practice of spending them on carpool lanes.
Historically, the diversion of funding from transit to roads took such insidious forms. For an instructive example from Owen Gutfreund’s book, roads advocates fought to get driver’s license fees and even inspection fees for fuel trucks recognized as road user fees, whose proceeds must be diverted toward roads. For another example from the same book, in Denver, the streetcar system was required to cover 25% of the cost of road maintenance on one-way streets and 50% on two-way streets, and as car traffic rose, streetcars both became slower and had to send over more money toward roads.
Another instructive case study is grade separations. It is to my knowledge universal that expressways and high-speed railroads, both of which must be grade-separated, pay for their own grade separations. In all other cases, who pays is determined by which mode is more powerful, and in the US, this is roads. As the national highway system was built in the 1920s, interurban railroads were required to pay for grade-separations, even when the rail came first. The practice continues today: in Kentucky, the railroad has to shoulder the full cost if it’s from 1926 or newer (Statute 177.110), and half the construction cost and the full planning cost if it’s older (177.170). In contrast, in Japan, grade separations are considered primarily a road project, and so the Chuo Line track elevation project was paid 85% by the national and city governments and only 15% by JR East (page 36). The segment in question of the Chuo Line was built in 1889; I believe, but do not know, that new rail construction in Japan is always grade-separated, at the railroad’s expense.
The situation in the US today is a surreptitious underfunding of transit, and at the same time a surreptitious overfunding of roads. It is not subject to democratic debate or even to the usual lobbyist funding formulas, but, like the obscure regulations that impede good passenger rail, hidden in rules nobody thinks to question. To pay for road mitigations and for parking, transit agencies will cut weekend service and reduce frequency. It’s bad enough when done in the open, but it’s done while claiming that transit is too expensive to provide.
In her book Dark Age Ahead, Jane Jacobs complains that freeways as built are good at getting people to macrodestinations (downtown) but not microdestinations (particular addresses within city center). In her example from Toronto, this is correct, but in general, each mode of transportation will be good at serving microdestinations in an urban form that’s suited for it. Cars are not good at serving an intact city center; but equally, transit is not good at serving suburban sprawl, and regional rail that’s not integrated with urban transit is not good at serving urban destinations away from immediate train stations.
The idealized job center in an auto-oriented city is the edgeless city. Even the edge city, as explained in Lang and LeFurgy’s now-paywalled article Edgeless Cities, is too dense, and becomes congested too quickly; indeed, Tysons Corner is infamous for its lunchtime rush hour conditions. Ideally, cars drive from low-density residences to low-density office parks, primarily on freeways but with fast arterial connections at both ends; the freeway network in the auto-oriented city serves an everywhere-to-everywhere set of origins and destinations.
In such an environment, transit can’t do well. The distance between suburban attractors is too great for an easy walk, and the roads are too wide and fast for a pleasant walk. Buses and trains can serve a general macrodestination (“Warwick Mall/CCRI”), but not individual microdestinations, not without splitting and cutting frequency to each destination or detouring and raising travel time. The buses serving Warwick Mall and CCRI have hourly frequency, and are a long, uncomfortable walk from the hotel in Warwick I needed to go to. Judging by the frequency, I’m not the only person who chose not to use them, and take a taxi instead; everyone who has a car or who isn’t extremely price-sensitive does. The only way transit can serve such a destination is by concentrating development near the station – in other words, making a mini-transit city in the sea of sprawl, which generally conflicts with the goal of easy station parking.
In a city, the opposite situation exists. It’s easy to just pronounce transit more suited to dense city centers than driving, but the situation is more complicated. Transit, too, thrives on good connections to microdestinations. It can’t serve employment that’s dense but evenly dispersed in a large area – people would need too many transfers, and the result would be service that’s on paper rapid and in reality too slow. Instead, it works best when all destinations are clustered together, in an area not many subway stations in radius.
In this view, one failure of urban renewal is its failure to recognize that most people who visit city centers are going to do a lot of walking, and amenities should make it easier rather than harder. Traditional urban renewal would build cultural centers and other projects at the fringe of the CBD, to help its growth: Lincoln Center just north of Midtown, Civic Center just southwest of the San Francisco CBD, Providence Place and Providence Station just north of Downcity. In New York and San Francisco, there’s at least rapid transit serving those destinations, mitigating the effects. In Providence, no such thing exists. It’s an inconvenient walk from Kennedy Plaza to the mall and the train station – it’s not too long, but it crosses Memorial Boulevard right when it turns into a freeway on-ramp. Walking to the Westin, immediately adjacent to the mall, is practically impossible without rushing across roads without crosswalks. Even the walk between the station and the mall, which were built together and are close to each other, is much worse on the street than on a map, again involving crossing auto-centric roads.
Organic city amenities do not look like this. If they cluster at the same location (for example, 125th Street in New York, or Thayer Street in Providence), they tend to be along roads that facilitate rather than hindering pedestrian movement. And if they don’t, they are all located along a rapid transit network in its shared service area, where it is still a tight mesh rather than a network of radial lines.
In view of the recent emphasis on parking policy, due to Donald Shoup but now mirrored by other urban planning and transportation experts, the observation is that in any city center, on-site parking is difficult to find. Even in cities that make downtown parking relatively easy to get to, people can’t hope to park at every single microdestination, so instead they trip-chain, driving into the city and parking but going to multiple points within the city, all within a short and easy walking distance from one another. This is roughly the urban geography of the French Riviera, which combines easy parking with a dense, lively center in Nice and a fair amount of urbanity on some streets even in auto-oriented secondary cities such as Monaco and Menton.
The connection to regional rail is that, historically, it descends from intercity trains, and therefore the conception of connecting the suburbs to the city is very macrodestination-driven. To name two egregious American examples, the Boston’s north side lines and Caltrain both connect many suburbs to the city while also connecting people to the suburban tech job corridor, but in reality miss the biggest job centers at both ends. North Station is two subway stations north of the CBD, and as a result ridership underperforms the south side lines; 4th and King is far enough outside the Market Street CBD that it’s not close to the CBD jobs – the proposed Transbay Center site, which is, is located near more jobs than all existing Caltrain stations combined. And if microdestination-level service to an already transit-oriented CBD is bad, then service to other urban destinations is worse: urban station spacing is wide, there’s no attempt to develop near stations, and the poor integration with local urban transit ensures that even people who could be willing to make the last-mile transfer don’t.
Gendered Innovations’ charts of trip chaining and gender breakdown of public transit riders got me thinking about how different systems of transportation handle a mixture of short and long trips. Eric Jaffe at The Atlantic Cities reports this and suggests that transit agencies orient physical features such as accessibility to the needs of women who trip-chain care and work trips.
But to me, the first observation is that although women trip-chain more, it doesn’t seem to be true that women are more likely to ride transit in the US than men just because of trip-chaining features. Instead, women traditionally have been less likely to have jobs requiring commuting, and the commute gap has been shrinking more slowly than the gap in employment.
This comes from the fact that trip chaining on transit is cumbersome in most cases. Both cars and transit have to deal with the time it takes to stop for an errand, but transit tends to handle this worse, unless it’s very frequent and has practically zero access and egress times. Transit cities instead get people to take their short errand trips on foot – since their neighborhoods are denser and have more mixtures of uses, they make retail and care trips attractive on foot. In light of the fact that walking is not useful for long commute trips and transit is not useful for short errands, we can construct the following typology of cities:
|Long \ Short mode||Foot, bicycle||Car|
|Car||New urbanist, small-town, auto-oriented dense||Auto-oriented|
Auto-oriented cities are the easiest: in those places, people drive for all purposes. Trip chaining can be done on a commercial arterial road, dropping off laundry or kids or buying something on the way to work, and because of ample parking availability, the time each additional link in the chain consumes is very small, since the longest access and egress time comes from navigating from the residential cul-de-sac to the arterial and from the arterial to the office park.
Traditional suburbs, common around New York and Chicago and sometimes in other old North American cities, are similar for trip-chaining purposes. In those areas, the urban form is suburban and auto-oriented, but work trips to the city are done by commuter rail or occasionally commuter bus, since the city is not as auto-friendly as the suburbs.
Transit cities too have their long-range commuter rail, but it is built as an extension of walking rather than of driving. Neighborhoods tend to have mixed uses, and there’s a concentration of retail development near the outlying stations, sometimes forming large secondary clusters but sometimes just acting as neighborhood centers. It could take considerable time to add more trips to one chain, especially if not everything is located at the train station. But conversely, the amount of time a single short trip takes is small, unlike the case for auto-oriented cities – the supermarket is right around the corner, and within five minutes’ walk are plenty of stores. When people walk, the concept of a single trip begins to lose meaning then. Potentially, every single purchase can be considered a separate trip, in which case the chaining becomes quite long.
In many places the transit is absent and people drive outside the neighborhood, while still doing errand trips on foot. This is the typology that characterizes different environments including new urbanism, traditional cities like Providence and Tel Aviv that have been made car-oriented, and auto-oriented modernist projects such as Co-op City. Those environments all differ in how trip chaining is done. In principle, it can be done on foot, but usually people who can drive do.
If my own experience is any indication, one feature of cities in this typology is that children and teenagers walk more. In Tel Aviv, my father drove me to elementary school on the way to work while (in later grades) I walked back, and I took the bus to and from middle school. Most trips my parents did in a car, but there was a reasonable number that were short enough to walk. I’d walk to farther destinations such as the cinema and the urban mall. The view of the North Tel Aviv middle and upper-middle class of the 1990s as I remember it is that the bus is fine for trips to school, but adults drive. I doubt I’d have had the same view if I’d grown up in New York, or for that matter in the Houston suburbs, where everyone drives or is driven.
Although most of the discussion about transit cities contrasts them with car-oriented cities, the other two typologies need to be examined, too. When adults and children trip-chain differently, children can get a distorted view of who transit is for (poor people, people who can’t drive yet), and the next generation will make the city auto-oriented; this is indeed what is happening in Tel Aviv, which despite population growth in the core is adding cars and spawning low-density suburbanization well outside the built-up urban areas.
Likewise, Cap’n Transit’s attacks on park-and-rides don’t quite capture what is wrong with the car/transit typology. A transit agency that wants to make it easier to trip-chain will want to concentrate development near the train stations, because that’s where it’s easiest to add minor trips without having to walk ten minutes out of one’s way. Of course in the middle of the dense city there’s development everywhere, which may well be orthogonal to where the subway is, but then trip-chaining becomes easier because each foot trip is so short.
The principle is that cars are a big one-time purchase but have a much lower marginal cost of usage. If one major class of trips can’t be done on transit – and chained trips generally can’t when they require the rider to wait for the next bus and the next bus will come in 15 minutes – then people will buy a car and then drive it even for trips they’d happily take transit to if they didn’t already own a car. The class of trips that can only be done conveniently by car needs to be kept small enough that people will use car share, take a taxi, or beg a friend who does own a car.
Thus what transit agencies and pro-transit politicians should devote more time to is appropriate development more than physical features of the transit system. Accessibility is important for so many reasons other than strollers. In contrast, the primary importance of using transit to extend the range of the pedestrian rather than provide a capacity boost for the car is precisely that transit needs minor trips to be doable on foot. A transit system that one needs to take to the supermarket may be technically successful, but it’s in a failed urban area.
Cap’n Transit is virtually alone in the transit blogosphere in opposing the Tappan Zee Bridge widening and replacement. Unfortunately, merely opposing a highway project, expensive as it is, is not enough; as we’ve seen in the failure of the ballot proposition to ban a highway tunnel in Seattle, opponents of highway expansion need to make it concrete and clear what transit alternatives there are. In the case of the Tappan Zee specifically, alternatives exist, but serve different markets, and it’s necessary to explain why the market that the Tappan Zee serves is not the most important to the region.
I propose a regional rail system instead, focusing on serving Rockland County and perhaps a few centers in Orange County. There are multiple lines crisscrossing Rockland County, with limited or no freight traffic, passing through old town centers that would make good regional rail stops and connecting to good alignments in North Jersey. For a regionwide perspective there are my original regional rail proposal and my more recent focus on connectivity from North Jersey to Lower Manhattan, but the important thing for the purposes of Rockland County is the question of which lines could be used. The Erie Main Line only goes to Suffern, but could collect passengers from the western parts of Orange County; the Northern Branch, including an abandoned northern end, goes as far north as Nyack; the Pascack Valley Line was abandoned north of Spring Valley but has an intact right-of-way as far north as Haverstraw; the West Shore Line goes north to Albany and has moderate freight traffic, easily accommodated in the off-peak if double-tracking is restored. There are so many options that the main question is which to activate just to maintain adequate frequency.
The main difference with any Tappan Zee proposal is that the existing rail lines go north-south, whereas the Tappan Zee is east-west. Fortunately, most existing movement is north-south. As can be confirmed by the 2000 census, Rockland and Orange Counties’ commute market toward Westchester and other suburbs accessed by the bridge is quite small: 18,000 to Westchester and Fairfield. The volume of commuters from those two counties to Bergen and Passaic Counties is somewhat larger (22,000), and that to New York City more so (27,000 to Manhattan, 14,000 to the other boroughs). And traffic over the bridge since 2000 has stalled.
Not only is the north-south or northwest-southeast market bigger than the east-west market, but also it uses the Tappan Zee when it could be diverted if there were alternatives. A breakdown of travel on the bridge reveals that 16% of eastbound travel is to the Bronx and another 15% is to the other four boroughs and Long Island; this could be done competitively by various transit options.
Thus, a transit option that emphasizes north-south connectivity and goes to Manhattan through Bergen and Passaic Counties is going to serve more people than adding more east-west connectivity. It could serve far more if North Jersey jobs clustered in Paterson, Hackensack, and other old city centers, but in fact they’re diffuse. It’s unreasonable to assume significant commercial transit-oriented development in North Jersey, though a few jobs in Paterson could still be captured; however, jobs in Manhattan, Brooklyn, and Queens could be served well.
Finally, to serve Bronx and Upper Manhattan jobs from both North Jersey and Rockland County, the trains should be combined with good bus service across the GWB. For example, bus lanes on Route 4 could be a strong start, especially if the trains are timed to connect to the buses. More speculatively, there’s a subway bellmouth allowing an extension of the C along the GWB, and relative to the cost of tunneling it should be inexpensive to extend the C as an elevated line toward Paterson over Route 4; the drawback is that the C is slow and would poorly serve the Bronx.
Although Rockland County is very sprawling, it has just enough old cities to anchor regional rail at the residential end. The effect is magnified if we can assume some TOD – for example, developing over the many parking lots currently in place in Nyack near the legacy Erie station – but as with commercial TOD, this is desirable but not very likely with the current political structure. Fortunately, American commuter rail works very well as a shuttle that extends auto-dependent commutes into cities that have no room for more cars; as a narrow alternative to constrained highways, it often succeeds, and would be a no-brainer compared to a bridge as expensive as the Tappan Zee.
The cost of reviving and electrifying the four lines proposed in my regional rail post (Erie Main, Pascack Valley, West Shore, and Northern Branch) is quite small compared to either the cost of bringing them to Manhattan or that of rebuilding the Tappan Zee Bridge. The cost of bringing the lines to Manhattan is substantial, but done right it would be much lower than the Tappan Zee Bridge’s $8.3 billion excluding any transit component.
If costs could be brought down, a new crossing, slightly farther north of the existing bridge, could work well for rail. The transit mode selection report discusses commuter rail on the new bridge, and the concept would be similar except that there should be more stations to serve local traffic better. A rail-only bridge would leave the Hudson Line north of Tarrytown, allowing west-of-Hudson commuters to access this job center and also ensuring no loss of frequency to the station, and then cross to Nyack. It would have to be underground in Nyack because the Palisades rise too steeply from the water, and would surface just west of the urban area. If all trains serving the line are EMUs, rather than diesels or even dual-mode locomotives, then the grade could be sharp enough to limit tunneling to the urban area of Nyack; the TMS report, which only considers diesels, proposes 2 miles (3.2 km) of tunneling, but EMUs climbing 4% grades could cut this by more than half.
The advantage of the east-west option is that it would serve Westchester jobs; while the commute market from Rockland and Orange Counties to Westchester is as mentioned not large, it clusters along I-287, especially in White Plains, and is thus somewhat more rail-serviceable. In addition, although the chance of commercial TOD is small everywhere in the US, it is larger in Tarrytown and White Plains than in Paterson and Hackensack.
On the other hand, if the costs could be brought down, they would be lower for everything, including highways. The same factors that cause transit construction costs to be so high in New York (namely, overstaffing, and poor contracting practices) apply to highways equally. In particular, the decision about what mode to favor should only weakly depend on cost, since relative costs both within transit modes and between cars and transit are not too different from in lower-cost countries.
To cut costs to a minimum while still providing acceptable first-phase service, the initial network could include only the lines that could be brought to Secaucus, with some track modifications near the station allowing Erie trains to terminate at the station parallel to the Northeast Corridor tracks; this still involves a fair amount of concrete pouring, but much less than a new tunnel to Manhattan, and the transfer could be made as convenient as that at Jamaica. In addition, trains could be mixed and matched: that is, to let a few of the Erie trains serve Manhattan directly, some Northeast Corridor or Morris and Essex trains could be cut to Secaucus. The main disadvantage is that no such option is possible with the West Shore Line and Northern Branch, and so it would be more useful in the western part of Rockland County than in the eastern part.
The selling point of the regional rail alternative is that, despite job sprawl, Rockland County residents are still more likely to need to travel to Manhattan than to Westchester. Thus, the promise of a one-seat ride to Manhattan on frequent train service, or at least a two-seat ride with the same quality of transfer offered to Long Islanders, could carry some political weight. One does not drive into New York out of love of driving; one drives into New York out of necessity, and making this less necessary could reduce some of the political will to spend billions more than required on widening a bridge.
Railvolution reports FTA numbers that say the average CO2 emissions of the New York City Subway are 0.17 pounds per passenger-mile (48 grams per passenger-km). That’s the equivalent of 114.6 passenger-mpg of gas, if you prefer to think in those terms. The presentation gives average seat occupancies, which we can also confirm with the NTD; it works out to about 4 car-mpg of gas. Other agencies can have somewhat different numbers, based on train efficiency and especially the local sources of power generation, e.g. BART has very low emissions coming entirely from the fact that the Bay Area has ample hydro power resources.
New York’s emission number, 4 mpg, may be familiar to you as roughly the emission-efficiency of regional diesel trains. Per ton of car mass the regional diesel trains do slightly better, since the regional train in question weighs 40 tons vs. 33-39 for New York’s subway cars, but this comes from making fewer stops. At agencies with very dirty power generation, such as the Chicago L, and even ones without very dirty power, such as the energy-hungry Washington Metro, the numbers are even lower, even though they’re electric and the regional diesel trains are not.
What we see is then that railroad electrification does not add too much to fuel economy. The question is then why the situation for cars is so different. The Nissan Leaf’s EPA-rated fuel economy equivalent rating is 99 mpg – almost as good as the New York City Subway, better than nearly all subway systems in the US. But if we try to break it down based on energy consumption, we get other numbers; the EPA just massaged the numbers to make plug-in hybrids look good.
The Leaf’s energy efficiency is 0.34 kWh per vehicle-mile, pardon the mixed units; the FTA’s numbers for major US subways range from 0.186 kWh per passenger-mile in high-seat-occupancy New York to 0.388 in low-seat-occupancy Chicago. This is not 99 mpg, unless one uses a fairly clean mixture of fuels; with the New York mixture, it’s 63 vehicle-mpg. So right off the bat, the official numbers underestimate the Leaf’s CO2 emissions by 36%, and overestimate its CO2 efficiency by 57%.
But even that doesn’t take care of inefficiencies in generation. Well-to-wheels, plug-in electric cars have about the same emissions as regular hybrids. This confirms the rough numbers we’ve seen from trains. The Tesla Roadster, a very fuel-efficient car, gets even better energy-efficiency even wells-to-wheels, but it also has much lower electricity consumption, and to get the right numbers it assumes electricity is generated from natural gas rather than coal.
Bear in mind, all of this assumes certain things about the grid mix. At the current US grid mix, on average electrification does not impact carbon emissions. Of course, since people need electricity for reasons other than transportation, any regime in which carbon emissions fall is one in which electricity becomes lower-carbon, and this would tilt the field in favor of all-electric vehicles, both cars and trains.
So, why electrify, if there’s no carbon emission benefit, why electrify? Two answers: air pollution, and, for trains, performance. Electric trains outperform diesel ones, and also cost less to operate in terms of both energy and maintenance. But electrification should be sold only on grounds that are in fact correct.
I’ve been reading Earl Swift’s The Big Roads, and the early biography of Thomas MacDonald had passages that jumped at me. Unlike Owen Gutfreund, who focuses on MacDonald’s industry ties and use of astroturf, Swift portrays MacDonald as a Progressive reformist who believed in better engineering as a way to improve society, literally paving the way to the future.
While he used special interests to further his goals, he was also concerned with efficiency. He first made his name as the chief of the Iowa State Highway Commission, where he built a road system with virtually no budget; neighboring states had several times the planning budget Iowa had. At the time, the building contractors had colluded, dividing the state into regions with each enjoying a local monopoly; this drove up costs twice, first by increasing construction costs, and second by requiring more maintenance since the work was shoddy. MacDonald’s contribution was to break up the monopolies and demand that contractors compete.
MacDonald also believed in personally instructing local officials and contractors in good road construction methods. He’d often be visiting construction sites and participate in construction, partly for the photo-ops but partly for showing the locals how good engineering is done.
As a result, MacDonald became famous among road builders for his success in building roads, and was made the head of the Bureau of Public Roads. Iowa at the time had one of the highest car ownership rates in the US, about 1 per 7 people (about the same as Manhattan today). The person who became Governor toward the end of his tenure in Iowa was anti-roads, but this did not slow down highway and car growth.
The importance of this for good transit advocates is threefold. First, it shows that it is in fact possible for government officials to promote good government and increase efficiency. Of course we must not neglect broader social trends, but sometimes well-placed competent individuals can make a major difference.
Second, it reminds us that many of the rules that are currently associated with government dysfunction were passed with opposite intent and effect back in the Progressive Era. Lowest-bid contracts were an effort to stamp out corruption; civil service exams were an effort to reduce patronage; teacher tenure was meant to make teachers politically independent; the initiative process was intended to give people more control over government. All of those efforts succeeded at the time, and took decades of social learning among the corrupt and incompetent to get around. Although programs built under these rules often turned out badly, such as the Interstate network, with its severe cost and schedule overruns, this was not due to the contractor collusion seen in the 1910s or today.
And third, it’s a warning to those who hope that placing well-meaning individuals in power is enough. Every person with power thinks that his power is used for good and wants to extend it. Thus, once MacDonald became head of the Bureau of Public Roads, he made sure to maintain control over highway funding and gave himself the power to sign contracts with states, which Congress was then obligated to fund.
Good engineering can improve engineering standards, but it cannot improve society. Although the decisions to tear apart neighborhoods were made by local officials more, of whom Robert Moses is the most infamous, the idea that a cadre of technocrats who look at cities on maps and in models know what cities ought to look like more than the people living in them was an inherent part of this attitude. Indeed, the 19th century impetus for suburbanization, using rapid transit rather than roads, came from the same class of reformists. The Interstate system was simply when they had enough money and power to impose their modernist vision nationwide.
The Tappan Zee Bridge is about to fall down. As a result, the replacement and widening project is in spare-no-expense mode. Ordinarily, widening a bridge from seven lanes to ten would be judged in terms of costs and benefits, after which the costs would be ignored as they always are for US road projects. But now everyone thinks New York needs this project, to the point that even transit and livable streets advocates are more worried about commuter rail tracks on the new bridge than about the costs of the entire project.
Cap’n Transit cribbed study numbers before they disappeared from the official website. The budget of the project, without the transit component, was about $7 billion, and is now up to $8.3 billion; this includes highway widenings at both ends. The transit component people are fretting about is another $1 billion for BRT and $6.7 billion for commuter rail.
To put things in perspective, consider the Øresund Bridge-Tunnel complex. Whereas the Tappan Zee is 5 kilometers of bridge, Øresund consists of 8 kilometers of bridge, an artificial island with 4 additional kilometers of road, and 4 kilometers of tunnel. The cost, including landworks on both sides, was a little more than €3 billion in 2000, which works out to $5.5 billion in 2010. The bridge-tunnel is narrower than the Tappan Zee replacement – four lanes of traffic plus two tracks of rail – but it’s also three times as long, and more complex because of the tunnel.
More importantly, if the Tappan Zee really needs that capacity, and width is such a constraint, they should build rail first, BRT second, and car lanes last. Roads will never beat mass transit on capacity per unit width of right-of-way. With all traffic from Rockland to Westchester County funneled through one chokepoint, and some centralization of employment (in Manhattan, White Plains, and Tarrytown), rail could work if it were given the chance. So the only environment in which a bridge with so many traffic lanes is justified is one in which the cost of ten lanes is not much more than the cost of four.
To be completely fair to irate Rockland County residents, more people use the Tappan Zee than Øresund, since the tolls are lower and it’s a commuter route. But not enough. The bridge is crossed by 138,000 vehicles per day. This means the replacement and widening project, excluding all transit improvements, is $60,000 per car. With normal commuter seat occupancy, it’s perhaps $50,000 per person. Transit projects in the US routinely go over this, but those are for the most part very low-ridership commuter rail projects. Second Avenue Subway, the most expensive urban subway in the world per kilometer, is about $25,000 per expected weekday rider.
Given the high cost, the only correct response is a true no-build: dismantle the bridge, and tell people to ride ferries or live on the same side of the Hudson as their workplace. Given expected ridership and Øresund costs, I believe the Tappan Zee replacement would make sense at $3 billion, with the transit components; without, make it a flat $2 billion. Go much above it and it’s just too cost-ineffective. Not all travel justifies a fixed link at any cost.