Minnesota is beginning to confront what promises to be the biggest shift in urban living since cars arrived in cities a century ago: The moment drivers let go of the wheel for good.

Self-driving cars are leaving the realm of science fiction and creeping into discussions about the future of transportation in the Twin Cities. Researchers say the technology could be required in new cars by 2030, leaving its mark on everything from parking ramps and road design to exurban sprawl and mobility for people with disabilities.

“We know it’s coming and it’s coming at a pretty rapid pace,” said Jay Hietpas, state traffic engineer at the Minnesota Department of Transportation. “And we just want to make sure that we’re ready.”

The state will step into the spotlight later this year when MnDOT tests a self-driving bus on snowy Minnesota roads — possibly even during Super Bowl festivities in February. MnDOT formed a group earlier this year to examine state laws about driverless vehicles. And planners are already speculating how cities will be reshaped when the technology arrives in earnest.

Many people may choose to abandon car ownership for robust sharing services, summoning driverless vehicles at a moment’s notice. Cars could travel closer together with less risk of accidents, boosting the capacity of highways. Commuters napping on their trip to the office may live farther away from work.

“Cities are just starting to figure out that they need to pay attention to this,” said Frank Douma, director of the State and Local Policy Program at the University of Minnesota’s Humphrey School of Public Affairs.

U researchers say fully autonomous vehicles that can operate without driver interaction may hit the market by 2025. But cars with self-driving features are already on Minnesota roads, such as Teslas equipped with autopilot systems that steer, brake and accelerate in freeway traffic.

The transition may be rocky. Autopilot was blamed in a central Minnesota crash earlier this month that left a Tesla upside-down in a marsh, but it turned out the driver had disengaged the system by hitting the gas. Once automation is fully implemented, however, U researchers believe it could dramatically reduce car-related deaths.

‘Have to start thinking’

The technology behind driverless cars is still evolving, but the latest vehicles navigate using 3-D maps to pinpoint their location within centimeters. Sensors look out for pedestrians and other vehicles, allowing the car to react in real time.

Driverless cars were being tested in nine U.S. cities last year, according to a report from consultant Accenture. But city planners and engineers here are starting to take notice and consider changes.

If people choose to forgo car ownership, there could be less demand for parking in urban areas since the driverless cars would spend more time in use and park closer together in faraway spaces, according to a U report prepared for MnDOT.

In Bloomington, Port Authority Administrator Schane Rudlang said city staff are mulling a recommendation that future parking garages built with city funds be designed for reuse later, perhaps as an apartment or office building, with flat floors and greater load capacities. Planners in Minneapolis and Hopkins said they are also weighing the technology’s effects.

“I think it’s important that local governments start having that conversation,” said Jason Lindahl, Hopkins city planner. “Because as a planner we’re hearing more and more about them.”

University of Minnesota Design Center Director Tom Fisher has been prodding mayors and city officials to plan ahead. They could one day reclaim roadway for sidewalks and green space, for example, since self-driving cars need less room to maneuver. The last thing cities should do is add lanes to existing roads, he said.

“We’re putting in roads right now that are going to last 50 years,” Fisher said. “So everything we’re doing right now is going to go through this transition.”

Advocates for people with disabilities are also tracking the technology, hoping it can reduce mobility barriers for people unable to drive. Minnesota nonprofit Mobility 4 All was founded for that purpose, and has been pressing its case with manufacturers.

“This technology could be transformative for people with disabilities,” said John Doan, the organization’s founder. “We want to make sure that developers design the physical as well as the software of the vehicles so that it is universally accessible.”

More cars, longer trips

Self-driving cars could also influence development patterns around the metro area, changing demands on freeways and transit.

Urban areas might grow more dense if parking needs drop, but the U report said autonomous vehicles could also encourage commutes to far-flung locales because people could do other things en route. In turn, governments might have to turn to pricing policies — replacing a gas tax with a per-mile tax, for example — to rein in sprawl, according to an analysis released by the University of California, Davis.

The technology has also prompted debate over spending money on expensive transit, like the Southwest light rail line.

“We’re sitting here fighting about a train — a billion-dollar train that it tells you when you have to be there and where to go,” said state Rep. Pat Garofalo, R-Farmington, who owns a Tesla. “Pretty soon here you’re going to have cars that can just pick you up wherever you are and take you to wherever you want to be.”

But others like David Levinson, the lead author of the U report, said large cities will still need high-capacity transit to serve busy urban areas.

“Cars, even driverless cars, can’t move as many people per hour past a point as trains can,” Levinson said.

The impact on freeway congestion is another unknown. MnDOT has been considering the technology as it plans for a future reconstruction of Interstate 94 between Minneapolis and St. Paul. Even if self-driving cars can travel closer together, there could be more of them, including empty vehicles making deliveries or picking up passengers.

What about winter?

Then there’s Minnesota winter. What will happen with self-driving cars when it snows?

Most driverless vehicle testing has been in warm climates like California, but Google, Ford and GM began snow testing over the last year and a half.

University of Michigan Associate Professor Edwin Olson, who worked on the Ford team, said the cars performed reasonably well in a test environment, but recreating snowy driving behavior poses challenges — like trailing other cars in a snowstorm.

“What you would be likely to see in that snowy scenario is an autonomous car stubbornly driving where the lane actually is underneath the snow,” Olson said. “But it could be profoundly stupid. It could be that’s where the snowplow just put a deeper pile of snow.”

Douma, of the Humphrey School, said MnDOT’s upcoming testing is an opportunity to show they work in winter.

“This would be the chance to show that Minnesota is in the game,” Douma said.

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