The A.V. club

How the automobile will reshape our cities, again

For more information about Nidhi Kalra's presentation and the RAND Corporation research on autonomous vehicles, go to

Last week, there was a little cycle of national and local news stories about the resurgence in public transit in America. Ridership hit 10.7 billion last year, the highest since 1956, according to a report from the American Public Transit Association.

Buried or missing in most of the news coverage was the fact that the overall share of transit, as a portion of all trips, has declined for 50 years. Public transit accounts for 5 percent of commute trips in America today. In 1960, it was 12 percent. In Sacramento County the number is about 3.1 percent, same as it was 10 years ago.

Bites has always been a transit fan and long believed we should reduce car trips and “vehicle miles traveled.” But last century’s mass-transit system isn’t coming back. And changes in automobile technology—specifically the shift to self-driving cars—may mean driving more miles in the future, not fewer. And that may be OK.

“Autonomous vehicles are very likely to be disruptive, and to change the way we shop and live and work,” says Nidhi Kalra, an information scientist with the RAND Corporation.

Kalra is giving a briefing at the Capitol on Wednesday, March 19, on the potential impacts of self-driving cars. In a new report, Kalra and colleagues say A.V.s may “fundamentally change transportation.” Perhaps in unexpected ways.

Major automakers predict that cars that can completely drive themselves will be on the market within 10 years. The most obvious benefit will be fewer crashes—the vast majority of which are caused by human error. That will save money and lives and mean fewer traffic delays. The report notes that self-driving cars may also lead to better traffic flow overall, and therefore more fuel savings. Likewise, fewer accidents may allow for lighter and more fuel-efficient vehicles.

And since the car is in control, the human “driver” is free to focus on more productive things like working, reading or watching baby goat videos. The opportunity cost of driving goes way down.

Earlier this month, the California Department of Motor Vehicles held an initial hearing on rules for A.V.s. For now, the DMV anticipates cars with an alert and licensed human driver onboard. But the technology is not far off for what the National Highway Traffic Safety Administration calls “Level 4” function: fully autonomous, possibly even unoccupied cars. This car could drop you off at the game, go park itself, perhaps at a nearby electric charging station, and come back to pick you up later.

That has all sorts of interesting implications for land use, transportation planning and urban design. Autonomous vehicles could reshape our cities. This city.

First, if the hassle of commuting goes down, people will endure longer commutes. As the automobile allowed for the suburb, so A.V.s could lead to even more sprawling sprawl. On the other hand, freed from the need for so much parking, city centers could get denser.

Speaking of parking, the RAND report offers this warning for cities: “By making proximate parking unnecessary, Level 4 AV technology may undermine the parking revenues that are an important and reliable source of funding to many cities.” But let’s not go there.

Autonomous vehicles will likely siphon some riders away from mass transit—multitaskers, or those have some physical limitation that prevents them from driving, or are too young or too old.

Of course, all those additional trips mean more cars on the roads—working against the congestion-reduction effect of self-driving cars. The question is whether the social and environmental benefits of A.V.s will outpace the costs.

A.V.s will be expensive, at least for a while. We could wind up with even more inequality in transportation choices—with a strata of affluent podcar people, leaving behind a smaller, poorer ridership share for buses and trains.

“But what if AVs are rolled out as a service, instead of just as a luxury vehicle?” Kalra asks. Fleets of networked driverless taxis and shared A.V.s could be the most accessible and affordable transportation option for many urban dwellers. Transit agencies could provide vouchers for these car-share services or offer their own. “We may need to rethink what we mean by ’mass transit,’” Kalra says.

We may need to rethink a lot. But how does a mayor or a transit agency prepare for these sorts of changes?

“The temptation is to try to figure out what the future is going to look like. But if our predictions are wrong, our policies are going to be very wrong,” Kalra says. The trick is crafting robust policies that work under different future scenarios. “In general we want to build in more flexibility. Agencies need to get better at making decisions under deep uncertainty.”

Because it is certain that our transportation systems will change.