By Michael Schwalbe
Cyclists tend to be skeptical about the safety value of paint. Spray-on bike lanes, for instance, can’t stop badly piloted cars from hitting people. But in part as a response to the rise in cyclist and pedestrian deaths in recent years, some cities have turned to using paint in a novel way: to create road art—also called asphalt art or ground-plane art—to wake up distracted drivers and slow them down.
Durham has tried it. When parents of children at Club Boulevard Elementary School complained to local officials about speeding cars near the school, the transportation department partnered with the city’s cultural and public art program and the Durham Parks Foundation to install an on-pavement mural at the intersection of Club Boulevard and Glendale Avenue.
A grant from Bloomberg Philanthropies, which has supported asphalt art projects in 64 cities in the U.S. and Europe, helped pay the $29,450 it cost to install the mural in 2021. The artist, Candy Carver, worked with a group of 39 local volunteers to apply the paint.
The mural, titled “Our Oasis,” is done in shades of blue, evocative of water, with multi-colored fish appearing to swim below the road. The crosswalks that frame the mural are filled between the lines with a rainbow assortment of jelly beans (though I think they’re supposed to be river stones).
The mural is—or was, at first—bold and eye-catching. Did it slow drivers down? Yes, maybe. For a time.
Before the installation, the city’s transportation department documented an average motorist speed of 39.2 miles per hour on Club Boulevard near the school. The posted limit is 35. A month after the mural appeared, the average speed dropped to 37 miles per hour. A year later the mural had faded considerably and the average speed on Club Boulevard was back to 39 miles per hour.
Evidence for road art’s safety-enhancing effects is, if not extensive and as yet verified by independent researchers, mostly consistent and suggestive of benefits. A 2022 study by Sam Schwartz Consulting, commissioned by Bloomberg Philanthropies, looked at 17 Bloomberg-funded projects in U.S. cities.
Looking across all 17 sites, the study concluded that road art projects yielded a 50% decrease in crashes involving pedestrians or other vulnerable road users, a 37% decrease in crashes leading to injuries, and a 17% decrease in the total crash rate.
The study, which used traffic observation methods, found a decrease in potential crash conflicts between cars and vulnerable road users at the Durham site. A follow-up survey by the city of Durham found a corresponding change in perceptions: the percentage of people who felt unsafe crossing the intersection fell from 85% to 6%.
People’s feelings about the mural are important, according to Rebecca Brown, Durham’s cultural and public art program manager. “We had a lot of volunteers that made that project possible,” Brown said. “One of the key takeaways,” she added, “was how place-making art and safety art can connect and make people feel empowered to change their landscape.”
Attributing safety gains to road art nonetheless remains tricky. As the authors of the Schwartz report said, “while we cannot infer direct causation, results generally indicated reduced crash rates after installation of art for most crash types across a range of settings, traffic control, and improvement types.”
Ralph Buehler, a professor of urban affairs and planning at Virginia Tech and an expert on bicycling safety, agreed that it’s hard to isolate the effect of road art. “If the art narrows the traffic lane or makes a turn more difficult or slower for motor vehicles,” Buehler said, “the effect may not come from the art but from the change in travel lane width, turn radius, etc.” In other words, road art might help as part of a larger package of safety improvements.
So what’s happening with road art in Chapel Hill? We have drain murals and a few painted crosswalks, but no fully painted intersections. Opinions vary on whether the town should go in for more road art.
“I would love to do asphalt art,” Bergen Watterson, Chapel Hill’s transportation planning manager told me, “especially around schools or recreation centers.” Watterson thinks road art projects are good community-building activities that “allow residents to feel a sense of ownership over the road, and hopefully drive more carefully.”
Not everyone is equally enthusiastic. Steve Wright, public art coordinator for Chapel Hill, said that an assessment by the town’s cultural arts commission determined that road art projects are more expensive to install and maintain, and less durable, than other public art options, such as drain murals, painted bike racks, and murals on OWASA water pipes.
Wright also noted that a 2013 memo from the Federal Highway Administration (FHWA) advised against eye-grabbing road art projects on the grounds that they don’t improve safety and can distract drivers. The memo cites no studies. It merely invokes an earlier FHWA ruling from 2001 that said crosswalk enhancements “have no discernible effect on safety or crash reduction.”
Despite FHWA discouragement, some cities have gone ahead with road art projects, claiming that the FHWA’s position is not based on evidence but on a stodgy interpretation of the Manual on Uniform Traffic Control Devices for Streets and Highways—the federal book of rules governing road signs and signals. Ames, Iowa, for example, was not deterred.
After Ames, home to Iowa State University, painted some of its crosswalks in diverse colors as a way to celebrate inclusivity, the FHWA sent the city a request that the crosswalks be removed. According to a story in the New York Times, the city council voted to ignore the letter.
The Times story quotes Michael Lydon, an urban designer who helps cities develop road art projects, as saying that the FHWA position is not grounded in data. “There are hundreds [of road art projects] around the country if not thousands around the world,” Lydon told the Times, “and I don’t know of any study that has been able to show that they are actually causing any problems.”
The story also reported that the FHWA was unable to point to any research showing that rainbow markings in crosswalks had a negative effect on safety.
What’s not in doubt is that we are facing a roadway safety crisis. While pedestrian and cyclist death rates have been declining across Europe, the rates in the U.S. have been rising. So it’s time to try anything that might slow drivers down and foster more community spirit behind the wheel. If road art can do that, and we now have evidence that it can, then bring on the paint.
Michael Schwalbe is a retired professor of sociology and an unretired cyclist. He has lived in Chapel Hill since 1990.