A country or region that is good at manufacturing cars can export them globally and earn hard cash. But what about public transportation? How can a city that has the ability to build good, low-cost public transport get rich off of it? There is an answer, but it is more complicated than “export this,” mirroring the fact that public transport itself is a more complex system to run than cars. This in turn relates to housing growth rates and urban economies of scale, making this the most useful in a large city with high housing production rates, of which the best example is Seoul. The good news is that the world’s largest and richest cities could gain tremendously if they had better public transport as well as high housing growth rates.
Infrastructure is not exportable
I wrote more than two years ago about the difference between dirty and clean infrastructure. Cars, car parts, and oil are exportable, so the majority of the cost of cars as a system are exportable, making dedicated regions like Bavaria, Texas, and the Gulf states rich. Green tech is not like that – the bulk of the cost is local labor. A large majority of the operating costs of a subway system are local wages and benefits; in New York, depreciation on rolling stock is less than 10% of overall operating costs. Construction costs are likewise almost entirely local labor and management, which is why they are determined by where the project takes place, rather than by which engineering firm builds the project.
The upshot is that Madrid and other low-cost cities can’t just get rich by building other cities’ infrastructure for them. They can’t build turnkey systems for New York and London at Spanish prices – the problems with New York and London come from local standards, management, and regulations, and while a Spanish engineering firm could give valuable advice on what high-cost cities need to change, it’s not going to reap more than a fraction of the construction cost saving in consulting fees.
Good transit as an amenity
What a city can do with low-cost construction is build a large subway network like Madrid, and use that as infrastructure to help local economic production. This works as both a consumption amenity and a production amenity. As a consumption amenity, it enables people to commute without needing to own a car, which reduces living costs and lets employers get away with paying less in nominal terms; this is a bigger influence on local firms, because international ones tend to use cost of living adjustments that make profligate lifestyle assumptions and factor in car costs even in cities where car ownership is low, like Singapore or New York.
As a production amenity, public transit also enables work concentration in city centers. This is separate from the observation that it allows workers to commute more cheaply – if a large city produces in a concentrated center, then without rapid transit, workers can’t get in at all. About 23% of people entering the Manhattan core on a weekday do so by car per the Hub Bound Report, but at the peak hour, 8-9 am, this falls to 9%, because the road capacity is capped around 55,000 cars an hour and a maximum number of parking spots for them. Auto-centric cities of New York’s approximate size exist, not by building massive road capacity to support comparable city centers, but by not having strong city centers to begin with. Los Angeles has maybe 400,000 people in the widest definition of its central business district, where in the same area New York has more than 2 million – and Los Angeles’s secondary centers, like Century City, top in the mid-5 figures before they get completely choked with traffic.
So what a city can do with cheap infrastructure is build a large subway network and support a large high-rise central business district and then use that to produce more efficiently. This is possible, but more complex than just exporting cars or oil, because to export cars one just needs to be good at making cars, and to export oil one just needs to have oil underground, whereas to produce out of public transit one also needs a solid economy in other sectors that can make use of the better infrastructure. I suspect that this is why Southern Europe keeps not growing economically despite building high-quality public transport – the Madrid Metro is great but there isn’t enough of a private economy to make use of it.
The connection with development
To maximize the use of a subway for its economy, a city needs to make sure development can follow it. This means that city center needs high job density, which includes high-rise office towers at the busiest intersections, and many mid-rise office buildings in a radius of a few kilometers. Neither the typical European pattern in which there are few skyscrapers nor the American pattern in which there are skyscrapers for a few blocks and then the rest of the city is subject to strict residential zoning is ideal for this. It’s better to have a city whose central few square kilometers look like Midtown and whose surrounding few tens of square kilometers look like Paris, with the occasional secondary cluster of skyscrapers at high-demand nodes; let’s call this city “Tokyo.”
Residential development has to keep up as well. A city region that has a strong private economy but doesn’t build enough housing for it will end up with capped production. Normally it’s the lowest-end jobs that get exported. However, two problems make it more than a marginal reduction in production. First, expensive cities have political pressure to allocate apartments by non-market processes like rent control, keeping less productive but politically favored people; a large gap between market rent and construction costs creates plenty of surplus to extract, and a mass exodus of firms from cities like San Francisco in such a situation starts from thee least profitable ones, and by the time it affects the most profitable on, the system is entrenched. And second, breaking a firm’s chain between high-end headquarters jobs in a rich city center and lower-end subsidiary jobs elsewhere reduces firmwide productivity, since many connections have to be remote; Google has problems with all-remote teams and tries to center teams in the Bay Area when it gets too unwieldy.
For one example of a city that does everything right, look at Seoul. It has low construction costs, around $150 million per kilometer for urban subways. Thanks to its low costs and huge size, it keeps building up its system even though it already has one of the largest systems in the world, probably third in ridership after Tokyo and Osaka when one includes all commuter lines. It also has high density, high-rise CBDs, and fast housing construction; in 2019 the Seoul region built around 10 units per 1,000 people, representing a decline since the mid-2010s, and the state has plans to accelerate construction, especially in the city, to curb rising prices. This is till a better situation than the weak economy and flagging construction in much of Europe, or the NIMBY growth rates of both much of the rest of Europe and the richest American cities.