THE WORLD THE TRACTION COMPANIES MADE.

It looked a lot like the so-called fifteen minute cities.

Picture living in a bustling neighborhood where all your friends, basic needs, and even your job are reachable by a quick walk or bike or bus ride. (Something many people experience, possibly for the first and last time, on college campuses.) In such a city, parking areas may have been reclaimed as urban greenways, chance encounters with neighbors might be more common, and small local businesses would proliferate and thrive.

This vision is sometimes referred to as “the 15-minute city,” a concept pioneered by Franco-Colombian scientist and mathematician Carlos Moreno. It means basically what it sounds like: Instead of expecting residents to get in their cars and drive long distances to work, run errands, and take part in social activities, cities should instead be designed to provide those kinds of opportunities in close proximity to where people live, reducing overdependence on cars and increasing local social cohesion.

Just what we need, a new sort of intelligent design to undo the effects of a century of not-so-intelligent design.

“It’s an invitation to reinvent our lifestyles and urban practices to build a better future, where sustainability, equity, and well-being are at the heart of our concerns,” Moreno writes in the book. I spoke with Moreno over Zoom and e-mail about the growth of the 15-minute city concept, some sources of backlash, and whom he hopes to reach with his new book.

Sure.  Chant the right worship-words and hope for the best.

Never mind that what he would like to achieve by fiat first emerged as if guided by an invisible hand.

[I]n a very profound way, the streetcar retains a hold over Los Angeles. In recent research, we found that places near now-extinct streetcar stops remain notably denser today.

As economists who study cities and local governments, we wanted to understand how cities evolve over the long run. The project was sparked in part by a conversation we had walking down Hollywood Boulevard with an architect friend who pointed out some still-visible influences of the streetcar. How much of a city’s development can be explained by market forces? And how much is due to the long reach of the past?

To answer these questions, we calculated the shortest distance to the now-extinct streetcar for each of Los Angeles County’s 2.3 million properties. We then assigned to each property the population density of its neighborhood, and sorted properties by their distance to the streetcar.

In Los Angeles County, streetcars and interurbans each played a role.  Before the Pacific Coast Highway, let alone surfboards, the Pacific Electric's Red Cars linked Redondo Beach to Santa Monica, with an interurban line along the Sunset Strip into Los Angeles.  Later came a subway from downtown to Hollywood.  Along the car lines, and particularly where the car lines crossed, the rent gradient, and central place theory in microcosm, did their work.

Locations less than half a kilometer from the extinct streetcar are more than twice as population-dense as locations two kilometers from the extinct streetcar.

Does this density come from many people in each housing unit, or from having many units–apartments or houses–on a piece of land? The figures below–using the same analysis as the one above–show clearly that population density near streetcars comes from having many housing units on land, not from having more people per housing unit.

If you seek a bar chart of the land values, simply look around.  As rent gradients preceded zoning, perhaps the first zoning boards in Los Angeles simply approved the existing land use patterns near the car lines.

This leaves two remaining potential culprits for the density at extinct streetcars: land use regulation and the self-reinforcing economic benefits of density, which economists call agglomeration.

Both of these explanations suggest that near the streetcar we should see more clustering of businesses or dense residential construction, and regulations that allow greater density. And this is just what we find. Places near the streetcar are roughly 45 percent more likely to be in non-residential use, and are 40 percent more likely to be zoned non-residential. For residential properties, the zoning of land near the streetcar allows 25 percent more units.

In fact, we found that the correlation between streetcars and density can be explained almost entirely by the correlation between streetcars and zoning. About half of the density near streetcars comes from properties near the streetcar having zoning designations that do not appear far from the streetcar, or vice versa. The rest of the difference between properties near and far from the streetcar comes from a different distribution of the same designations. For example, areas near and far from the streetcar may both be zoned for some multi-family residential units, but the area near the streetcar is zoned more heavily this way. In short, once we account for zoning, there is no difference in density between properties near and far from the streetcar.

There are two extensions of the research: first, the limits to those agglomeration economies (think of a neighborhood as a club good with crowding) eventually make further building up inefficient; second, there's an additional complication in the rent gradient in which people trade off commuting costs for additional space.  It's possible that phenomenon had already presented by the time the first zoning board convened.

Get away from the cities and the car lines, and what M. Moreno envisions is what emerged along the interurban lines, only with improved telecommunication over a century ago.

In less densely populated areas, distances are generally greater and services less concentrated. The focus could be on efficient alternative methods of transport such as electric bikes, shuttle services, or car-sharing solutions to make travel more convenient without relying solely on the car. Using multifunctional spaces that can serve different purposes depending on the time of day — for example, a space that serves as a market in the morning, a café in the afternoon, and a meeting place in the evening — can be effective. Small towns and rural areas can also benefit from increased use of technology to access services such as telemedicine, online education, and digital government services, reducing the need for physical travel.

From there, that Grist article degenerates into more worship-words, which we might summarize as "do things our way or choke on your pollution."  Left unsaid: whether the inhabitants of those interurban suburbs are members of the laptop class, or engaged in running boutique businesses for tourists.  Riding the cars to mill or office is so last century.

Alas, you cannot change the logic of the rent gradient.  Bill "Future of Where" Fulton explains.  He lives near the peak of a local rent gradient, in San Diego.

We take the car out maybe once or twice a week. It’s a 10-minute walk to the supermarket (with another even closer on the way). My optometrist is a 5-minute walk; the UPS store and my bank are literally across the street from where I live. My office is a 20-minute walk or a 10-minute light-rail ride. From my place I can easily walk across the street to the train station, from which I can take trains and buses almost anywhere in San Diego and Southern California, including the airport, which is a 10-minute bus ride away. Two of our major music venues are also walkable. It’s even a short walk to our local ferry terminal. And that’s not including the dozens of bars, restaurants, and coffee shops in close proximity to where I live. The other day I got called for jury duty – and the courthouse is four blocks away.

Which is fine if you have the means.  If you don't have the means, enjoy the scurry.

So all the time, you see ordinary folks working in 15-minute cities who are seriously inconvenienced because these neighborhoods are crowded and expensive. Many workers have to walk a long distance or even take transit to get from their car to their workplace. (In a neighborhood where another high-rise is always going up, I see construction workers all the time on the train and walking down the street.) And people often have to commute long distances to work in a 15-minute city; in my neighborhood, service workers often live in Tijuana and endure a commute of an hour or more, crossing an international border, to their jobs nearby.

Many people prefer to live far away from their jobs or in suburban locations, and that’s fine. Lots of San Diego workers who live in Tijuana do so because it is so much less expensive and that makes sense too. (And obviously most service workers generally have to work onsite and can’t work remotely.) But the evidence suggests that lots of people who work in a 15-minute city would like to live in one too, but they can’t simply can’t afford it.

Put another way, the shipping clerks, tellers, baristas, wait-staff and kitchen helpers, and possibly the security officers at the courthouse are all enduring the commute (which in San Diego includes a reincarnated interurban) in order to make Mr Fulton's fifteen minute city possible.

Maybe the best thing to do is for the planners and the government agencies to go away.

We simply need to build more housing in the United States, period, and more of it needs to be located in 15-minute neighborhoods. This doesn’t necessarily mean that all new housing has to be located in existing neighborhoods. After all, most new housing built in the United States is built in greenfield locations. But those greenfield locations need to have more 15-minute aspects to them – as, increasingly, suburban town centers do indeed have.

A faux town center that didn't get started where the car lines crossed or the interurban stopped each hour is likely to be yet another toy for metrofexuals, with the hired help dependent on their car or perhaps what passes for the transit authority's bus services these days.  Additional regulatory constraints aren't going to help.

Some developers of suburban master-planned communities have figured this out, essentially switching from communities that revolve around golf courses to communities that revolve around town centers. But it’s not the norm, and most suburban developers just want to build what they know how to build, which usually means carpetbombing a greenfield site with a bunch of houses.

That's the phenomenon we observe in Greater Chicago, people build big far down the rent gradient and hope for gasoline to stay cheap.  No wonder Our Intellectual Betters get disrespected for their fifteen minute city fetishes.

That’s why 15-minute suburban neighborhoods actually requires the public sector to do real planning as well – and sometimes to invest at the front end in infrastructure and facilities. In other words, sometimes the local city or counties has to serve as the master developer in order for suburban 15-minute neighborhoods to come about.

Housing affordability is a much trickier problem, for the very reason I mentioned above: Affluent folks bid up the price of high-amenity neighborhoods. I have struggled for my entire career about how to deal with this problem.

On the one hand, I believe strongly that the private building industry can provide a lot more housing – at scale – than the government or the nonprofit sector will ever be able to do.

On the other hand, private real estate development in a desirable urban neighborhood tends toward higher-density and higher-cost housing. My neighborhood used to have a wide variety of low- and mid-rise housing, but now all anybody builds is high-rises with million-dollar condos and $6,000-a-month apartments. Which means that, like it or not, some housing in a neighborhood like mine has to be income-restricted, in order to maintain diversity and give folks who work here a chance to live here.

Those laws of conservation in economics are a pain, aren't they?