All bike lanes are not created equal.
Protected bicycle lanes – separated from traffic by physical barriers like parked cars, a curb, landscaping or posts – may make cyclists feel safer and encourage more people to ride, but they vary in terms of the buffer they provide. Some leave cyclists more vulnerable to injury than others.
Overall, street-level protected bike lanes are high risk for injury, while conventional bike lanes — separated from traffic by painted lane markings, but without physical barriers – are less risky, possibly because they are often installed on safer roads to begin with.
Protected bike lanes raised from the road are the safest.
Those are the highlights of a new study that looked at how bike lane design impacts safety.
The report, released on Thursday by the Insurance Institute for Highway Safety, a nonprofit financed by the insurance industry, looked at the injury risks associated with different types of cycling infrastructure and suggested ways to make riding safer. Research was conducted in collaboration with George Washington University, Oregon Health and Science University and New York University.
The study comes at a time when cycling fatalities are on the rise. Bicyclists’ deaths have increased 25 percent since reaching their lowest point in 2010, according to the study.
When researchers compared the likelihood of having a crash or fall on a major road with no bike infrastructure to two-way protected bike lanes, the risk was much lower on lanes on bridges or raised from the road like those within green ways than on lanes at street level.
“A cyclist on a protected lane at street level is likely to encounter vehicles at intersections, driveways and alleys more often than on a protected lane enclosed within a bridge or greenway,” Jessica Cicchino, vice president for research at the Insurance Institute and lead author of the paper, said in a statement.
The combination of busy intersections, junctions and two-way bike lanes was found to be particularly challenging for turning drivers, as they needed to view oncoming traffic as they turned and looked in both directions for bicyclists.
“Pedestrians also sometimes enter street-level bike lanes, which can cause cyclists to swerve and fall,” Cicchino added.
Whether the lanes are one- or two-direction were also among the factors that affected the likelihood of a crash or fall, the study found.
“There is evidence that protected bike lanes help prevent the worst crashes,” Cicchino said, referring to recent research from the University of Colorado and the University of New Mexico that found that cities with more feet of protected bike lanes per square mile had fewer fatalities and serious injuries to all road users than other cities. “What our study shows is that certain locations are better than others for this type of infrastructure.”
However, the bicyclist crashes seen in street-level protected lanes weren’t the most severe. Most fatalities involving motor vehicles occurred mid block, while cyclists in protected bike lanes in the study collided with vehicles most often at intersections or junctions with driveways and alleys.
Local roads had the lowest risk of a crash or fall among the routes analyzed for the study. Conventional bike lanes also had a lower risk than major roads, though the risk was higher at intersections.
The study noted that it was not clear why protected bike lanes would be more dangerous than conventional bike lanes, but it may be due to the locations cities choose for protected lanes.
“Typically, protected lanes are installed on busy roads that pose more of a risk to cyclists in the first place,” Cicchino added. “Our finding that conventional bike lanes were less risky doesn’t mean that cyclists on roads with protected lanes would be better off without that separation.”
The report recommends that cities locate protected bike lanes where there are fewer junctions if possible or to consider raised cycle crossings, which have been found to improve safety on protected bike lanes in Europe, and to take measures to prevent pedestrians from entering bike lanes.
To learn more about the study, click here.