Research highlights safety tradeoffs of electric scooter speed limiters

Since the first shared electric scooter program was launched in the United States five years ago, they’ve swarmed cities across the country due to their inexpensive cost, clean energy output and versatility as a last-mile transportation option. As their popularity has grown, regulating their usage on public roadways and streets has arisen as a complex issue.

Many cities have turned to speed limiters to address concerns about rider and pedestrian safety. But a new study from the Insurance Institute for Highway Safety corrolates lower travel speeds with more e-scooter usage on sidewalks, which are associated with more frequent injuries.

“Our results show that restricting scooters to low speeds offers a trade-off,” said Jessica Cicchino,vice president of research at the Insurance Institute for Highway Safety and the study’s lead author. “At slow speeds, riders are more likely to choose the sidewalk over the road. That puts them in less danger from cars but could mean more conflicts with people on foot.”

Researchers compared e-scooter rider behavior in Austin, Tx., where the maximum speed is 20 miles per hour, and Washington, D.C., which has a 10-miles-per-hour limit, to better understand the effect of speed limiters. A brief about the findings notes that many cities cap scooters at 15 miles per hour. Washington, D.C.’s limit is among the lowest in the nation. Notably, limiters are put on shared scooters. Privately owned scooters are harder to regulate.

“In both cities, e-scooter riders overwhelmingly rode in bike lanes where they were available. Where there were no bike lanes, however, D.C. riders were 44% more likely than Austin riders to choose to ride on the sidewalk,” the brief says, even though vehicle traffic was heavier in Austin. “Overall, however, riders tended to choose the sidewalk when motor vehicle traffic was heavier, as well as on arterials and two-way roads. In contrast, the researchers saw an increase in e-scooter riders in vehicle travel lanes on weekends, possibly because of lighter traffic.”

The study highlights a safety conundrum that’s being considered by both administrators and riders alike. For riders, traveling on the roadway increases the risk of a severe or even fatal accident. Traveling on the sidewalk, meanwhile, puts pedestrians at risk of less serious but potentially more frequent accidents. Based on the research, having a lower speed limiter encourages sidewalk riding.

“E-scooter users clearly take risk into account when choosing where to ride,” Cicchino said. “Many are also conscious of the risk of hitting a pedestrian. E-scooter speeds were lower on sidewalks than on roads or bike lanes in both Austin and D.C.”

In the study, researchers found that one in five e-scooter riders traveled at 10 miles per hour or higher on sidewalks in Washington, D.C., while two in five did the same in Austin. Many riders in Austin rode at 15 miles per hour on the sidewalk.

Total bans on sidewalk riding don’t seem to be effective. An analysis of Washington, D.C.’s central business district, where e-scooters aren’t allowed on the sidewalk, found that two-thirds of riders did so anyway in locations where there weren’t any bike lanes.

“Slowing down the fastest sidewalk riders should help prevent crashes and reduce the severity of injuries when e-scooters hit pedestrians,” Cicchino continued. “The clear preference for bike lanes also gives communities another reason to focus on expanding their bicycle networks.”