Study: Bike Lane Prompts Reduced Traffic Speeds

Marking a bike lane with cones or other delineators can dramatically reduce driving speeds in adjacent traffic lanes.

1 minute read

June 4, 2024, 7:00 AM PDT

By Diana Ionescu @aworkoffiction


Close-up of white delineators with red stripes denoting green painted bike lane in Berlin, Germany.

michelsass / Adobe Stock

A new study from Rutgers University-New Brunswick reveals that a new bike lane at a high-traffic New Jersey intersection led to lower traffic speeds when cars approached.

Kitta MacPherson describes the results, noting that “To analyze the effect of the bike lane on traffic speeds, the researchers employed computer vision techniques to classify the speed and trajectory of more than 9,000 motor vehicles.”

As many traffic analyses have identified speeding as a contributing factor in a majority of crashes, inducing such a “traffic calming” effect with a bike lane could enhance road safety and decrease the risk and severity of crashes, the researchers said.

Delineating a bike lane with cones led to a 28 percent reduction in maximum speeds, a significant improvement over the presence of just a painted bike lane (which led to an 11 to 15 percent reduction in speeds only for drivers turning right). “Younes hypothesized that drivers slow down when they see a bike lane marked with the cones because the driving lane is narrower and requires more concentration, and it’s easier to notice cones or planters or some other space delineator than it is to spot painted lines on the road surface.”

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