Consider the 15 mph City

When San Francisco’s MUNI spent big money on a “central subway” to Chinatown, I was doubtful. One recent Saturday, though, I revived the gallery-hopping I did before the pandemic, taking the train from Berkeley into the city, walking to one gallery near Embarcadero Station, then taking a tram past the ballpark to the CalTrain Station, where I switched to another tram to head south to Minnesota Street’s Dogpatch cluster of galleries and artists’ studios.

While talking with Ward Schumaker, whose ceramics show I came to see, he mentioned the convenience of the T line now that it runs to Chinatown. He was right: the T got me to Union Square quickly, connecting directly to BART and MUNI’s Powell Street Station, where I caught a train to downtown Oakland and another to Berkeley. The tram I took initially past the ballpark was the long way around, slowed by Giants fans on their way to a game. Taking the T back was a straight shot. What had been an ordeal I tended to avoid is now considerably faster, easier, and more attractive.

In Energy and Equity (1974), the social critic Ivan Illich argued that 15 mph was a reasonable upper limit for human movement. He took bicycles as his metric, unaware that bike speeds would increase along with those of every other kind of vehicle. He was ridiculed for this assertion, but if we think of it as an average speed for movement other than simply walking, 15 mph seems reasonable in most local contexts. With it in mind, we could distinguish among trains, trams, buses, cars, trucks, and bikes, and their various pathways and needs.

Currently, we mix aided-movement modes irrationally. Local, non-arterial streets are designed mostly to accommodate emergency vehicles, delivery trucks, and SUVs. Arterial streets are designed to funnel cars and trucks across town at higher speeds, in theory, than local streets permit. In reality, they jam up at certain times of day, slowing movement to a crawl. At other times, their permitted speed makes them hazardous to pedestrians trying to cross them. “Calming” the traffic on these arterial roads is a current urban fixation, as are efforts to make it safer for bikes to interact with cars and trucks on these same throughways.

What is transit for?

Walkable urbanism needs local mobility. We need to turn our idea of regional transit inside out, making local access as important a goal for it as geographic reach and point-to-point speed.This is not to say that the latter goals are unimportant. Regions need backbone systems with reach and speed, but they also need locally serving networks that do this efficiently, just like the T line: frequent; direct and accessible to and from the neighborhoods served; and connected to the regional transit corridor along Market Street.

The example of San Francisco’s central subway also suggests that local jurisdictions will be crucial to making walkable centers more widely accessible. Along major transit spines, bus routes that connect each station to likely destinations, not just take riders back and forth from their places of residence, will set the stage for better future service—with trams instead of buses, perhaps, on well-traveled routes. (When trams have protected rights-of-way, they’re faster than cars on congested arterials. Reducing the number of lanes on those arterials is easier if there’s a convenient transit option for getting from point A to point B.)

Precedents and portents

In 1989, I visited the late U.C. Berkeley Professor Richard Bender and his wife in Tokyo, where Bender was a visiting chair at RCAST, the research campus of Tokyo University. They were living in Mejiro, an area of the city served by the Yamanote Line, an elevated “circle line” run by Japan Railway. Bender told me that Mejiro reminded him of the Brooklyn of his youth, the way the station opened out to a shopping street, with residential neighborhoods behind it. It takes in Gakushuin University (shown above), the 19th century “Peers’ School” founded to educate Japan’s aristocracy. Its presence gives Mejiro a “university city” feeling not unlike Berkeley. Almost 30 years later, I visited Oyama at his Nest Café in a much-denser Mejiro. The lane I walked down in 1989, one car plus one person wide, is still there. Fire and garbage trucks in Tokyo (seen below) are scaled to the lanes. Car registration in Japan, based on engine displacement, led to “micro-cars,” like Europe’s Smartcar. In France, the EV revolution spawned the Ami, a two-seat Citroen “city car” with a top speed of 25 mph and a range of 75 miles; drivers as young as 14 can own or rent them. Sweden’s Luvly makes a four-seat EV (seen below at right) with a top speed of 56 mph and a range of 62 miles, shippable in a flat pack, with two removable batteries weighing 33 pounds each.



Established automakers have tended to convert their existing, full-size gas-powered models to EV. Indeed, GM recently announced that it will stop producing its compact Bolt EV sedan to focus on its large EV pickup. But in cities, car use is mostly local, so speed and range are less important than cost, convenience, and ease of parking. On this basis, EV pickups and SUVs could soon be an endangered species.

City streets were planned and designed for large vehicles. Efforts to make streets safer for walking and biking take this as given, but a shift in vehicular scale, reflecting today’s urban realities, would allow us to rethink the streetscape entirely, reallocating the flow of cars, bikes, and pedestrians, the way we allot space to them, as well as how cars and bikes are parked, recharged, and potentially shared.

Rethinking’s “how come”

A welter of arguments is made for changing the urban condition where it meets the street. The arguments have committed and passionate advocates, but they often overstate their case and push their point of view past what others consider reasonable. Cities struggle to make sense of their demands, often put forward in terms of urgency, citing climate change, traffic fatalities, and other reasons to take action. 

The solutions these advocates put forward, while well-intentioned, are too narrow. They miss the possibilities for urbanity inherent in a broader rethinking of our cities as an ecosystem. This was what Illich meant when he suggested that we slow down and live in cities that get us to places in a “fast enough” manner. In truth, he was asking how cities support human life, and how to restore what he called their “conviviality.”

Transit at different scales needs to be at the heart of this. What we’re really rethinking is how our cities work, how “walkable urbanism” is activated by locally serving transit that supports walkable destinations by making them accessible at “Illich speed,” as I’ve defined it: an average travel time of 15 mph in town, some of which involves walking or biking. By re-establishing stations and stops as ordering devices for city districts and neighborhoods, walking/biking can again become the main way people use them.

Where topography is an issue, supporting transit like the hillside escalators in Hong Kong can be introduced. As I saw in Rome in 1998, small “micro-buses” there take people from one district to another along its main walking routes, so they can forgo cars or minimize their daily use. Use taxes on private cars here in the United States could help pay for less impactful alternatives. Like water and power, private cars could be charged a base rate for reasonable size and local travel, with the cost rising as size and use increase. 

When urban politicians and developers picture the 15-minute city, they still focus on the big moves—sports facilities, convention centers, regional transit hubs—that have their place and value in any large city. But the 15-minute city concept actually hinges on activating secondary and tertiary centers, one district and one neighborhood at a time. With transit ridership still down nationwide and systems facing huge budget deficits and possible cuts, a flexibility of approaches to transit, large and small, seems not only timely but necessary. 

Much has been made of the Bay Area’s deflating tech bubble, but it’s restoring a less drastically tiered economy that invites a more locally based approach to city-making. We share this situation with most other cities. Exigency forces choices, and local activation is a bigger factor. Achieving it needs safe and convenient, transit-aided local access—much easier to accomplish if we think of the 15-minute city as a 15-mph one. 

Featured image: San Francisco’s MUNI. All photos courtesy of the author.


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