Future Tense

Can Self-Driving Cars Handle Boston’s Infamously Congested and Confusing Streets?

Cars and a biker at a snowy intersection in Boston.
Traffic flows (smoothly, for once) through downtown Boston.
Maddie Meyer/Getty Images

Boston drivers, pedestrians, bikers, and T riders will soon share the road with self-driving vehicles. The city announced in a statement Wednesday that it has granted permission for Boston-based autonomous vehicle company nuTonomy to test its fleet of autonomous cars on all city roads. The company had previously been limited to testing its cars in the Seaport, a neighborhood downtown that’s largely nonresidential.

Boston’s Mayor Marty Walsh said, “If deployed thoughtfully, shared fleets of autonomous vehicles could offer the City of Boston the potential to improve safety on our streets, provide equitable connections to the MBTA, and offer a new source of mobility to all Boston residents.”

Following Walsh’s announcement, Gov. Charlie Baker and mayors of several Massachusetts cities announced on Thursday a regional agreement to allow the expansion of autonomous vehicle testing in cities throughout Greater Boston.

NuTonomy cars have their work cut out for them. A recent report from INRIX Global Ranking found Boston to have “the worst traffic in the country,” with Greater Boston commuters spending 14 percent of their driving time in bumper-to-bumper traffic, compared to New York City’s 13 percent and Los Angeles’ 12 percent.

Boston’s traffic woes are only compounded by the city’s non-gridded streets and “maddening intersections.” (Boston magazine has tried to debunk the popular urban legend that they originated from cow paths.)

And to top it all off, nuTonomy cars will have to contend with Boston drivers—so notorious that the Boston Globe once ran an op-ed titled, “Boston driving: So bad it needs its own lingo?” Auto insurer Allstate reported in 2017 that Boston drivers are 179 percent more likely than the national average to get in accidents, ranking them last in a list of 200 American cities. (Particularly bad drivers are sometimes called Massholes.)

William Messner, a mechanical engineering professor at Tufts University who worked on early driverless car technology in the aughts, says he’s “very optimistic” about the potential for self-driving cars to bring safer and more accessible transportation, including for people who are unable to drive. But he also sees a unique set of challenges in Boston, pointing to a city that’s “not gridded” and has “windy streets, poor weather, lots of roundabouts or rotaries, crazy intersections.” He also pointed out that the “streets are not straight,” and some are “very narrow.”

NuTonomy has already had some practice navigating Boston’s streets. The company, which spun out of MIT in 2013, has been testing its cars in the Seaport since the beginning of 2017. (Walsh suspended self-driving car testing in Boston in March, after a self-driving Uber struck and killed a woman in Arizona.) NuTonomy said last year its cars drove more than 600 miles without accident. It also ran two passenger pilot tests with rideshare company Lyft.

“We are proud to be the first company authorized to operate autonomous vehicles on public roads city-wide in Boston,” Karl Iagnemma, president of nuTonomy, said in the city’s statement. But there have been some challenges: For example, last February, the nuTonomy cars were having trouble identifying flocks of seagulls that often congregate in the Seaport during winter.

The cars won’t hit the roads immediately—nuTonomy first has to map the area so sensors and software can be programmed accordingly. And there will always be two humans in the cars, even when they’re in self-driving mode: one to monitor the car’s systems and one ready to take the wheel, if necessary. Like if a flock of seagulls show up suddenly.