The Impacts May Be En Route, but Cities Should Plan for AVs

Self-driving cars could make any number of impacts on cities in areas including traffic congestion, parking or even suburban sprawl, prompting officials to begin thinking about how to plan for these changes.

But despite the attention given to robotaxis, sidewalk delivery robots and other related next-gen automated devices, autonomous vehicles (AVs) are not a big piece of the transportation ecosystem, and it could be some time before cities and regions will experience sizable impacts, researchers said.

“Yes, we need to be looking at it. Yes we need to figure out the readiness. But also, our hair’s not on fire,” is the way Nico Larco, director of the Urbanism Next Center at the University of Oregon, described the current AV climate.

Larco was part of an online panel Thursday organized by the Urbanism Next Center to discuss the recent study Shifting Spaces: Understanding the Impacts of Autonomous Vehicles on Land Use.

Waymo’s robotaxis, he said, provided a mere 0.006 percent of all U.S. trips last year.

“If you triple that you are at the mode-share for skateboards,” he added. (Skateboards account for roughly 0.14 percent of trips in California, according to the California Household Travel Survey.)

Even if AVs are not a significant piece of the larger transportation ecosystem, their numbers are growing, and the expansion of robotaxis from Waymo, Tesla, Zoox and others is notable in cities such as San Francisco, Los Angeles and Houston.

These new forms of mobility could ultimately impact how cities develop. Will they reduce the need for parking lots? Will they encourage more dense development? Or will they lead to suburban sprawl? These are just some of the questions researchers and planning officials are considering.

Much depends, Larco said, on whether AV technology evolves as a fleet of robotaxis as we are seeing today, which could reduce the need for parking lots and garages, and encourage denser development. Or, if the market moves in the direction of individual, privately owned AVs, that could make driving less of a burden but encourage sprawl, leading to higher vehicle miles traveled and congestion.

“We do not yet fully know the rate AVs will penetrate the market, and because there’s so much uncertainty still, land-use implications are going to be massive,” Marisa Laderach, principal regional planner at the Southern California Association of Governments (SCAG) and California Clean Cities Coalition director, said during the panel.

“We want to make sure that we’re weighing potential benefits against potential risks, that we are deploying AV systems that advance, rather than hamper, our regional goals,” she said.

SCAG tends to prefer a more shared AV deployment system, rather than private, personally owned cars.

“AVs are not necessarily this kind of stand-alone mobility solution. We’d like to see them integrated as a component of mobility hubs,” Laderach said, describing these as locations where transit, shared vehicles, and active transportation all come together. SCAG’s Connect SoCal 2024 transportation plan identified more than 700 potential mobility hubs across the organization’s six-county region.

“These are areas where we really intend to see land use shifting away from traditional parking, and more toward multimodal infrastructure foundation to help support seamless transfers between different modes of travel,” Laderach said. “And this would offer us an opportunity to integrate AV infrastructure at these key locations.”

The study of AVs and how they can impact areas like land use is a way for public-sector agencies to get out in front of the technology, Laderach said, indicating scooters and other forms of micromobility don’t require the same level of supportive infrastructure and participation from agencies and other parties.

“I feel like because AV is such a complex thing and because it requires so much more of that supportive infrastructure, for better or worse, we have to proactively think about these things,” Laderach said.

With so much about the future of AVs still up in the air, cities could be forgiven for not having all of the answers when it comes to policy direction. Larco advises “pilot like crazy,” even if it doesn’t lead to changes in regulation.

“But it is changes in knowledge,” he said. “It’s tremendously helpful to pilot, try things out, see what impacts there are, so that you can make better decisions at the local level.”

In a “quick-moving world,” he said, it’s okay to put in regulations with the idea of revisiting them in a year or two to see how they should be revised.

The technology is evolving quickly, he said. “But it’s not like, tomorrow.”