Chicago Left Turn Traffic Calming Reduces Crashes

The city installed reflective posts and speed bumps at dangerous intersections to induce drivers to take left turns more slowly and carefully.

1 minute read

January 24, 2023, 7:00 AM PST

By Diana Ionescu @aworkoffiction


Crosswalk in Chicago with newly installed yellow delineators and speed bumps

City of Chicago / Left turn traffic calming

A traffic calming element installed at 18 Chicago intersections is successfully slowing left turns, reducing the risk of collisions with pedestrians, reports Monica Eng in Axios. The project is part of the city’s efforts to reach its Vision Zero goals and eliminate pedestrian deaths. 

According to Eng, “Left turns were involved in 40% of crashes that led to serious injury or death from 2017 to 2021, according to city data.” David Smith, the city’s Complete Streets director, says data from a pilot program shows a 25 percent reduction in crashes at intersections where the change was made.

Some residents expressed frustration with the new infrastructure, inadvertently proving the device’s efficacy: “All they have done is further slow traffic,” one NextDoor commenter complained. Which is, after all, the point. “If you hit a speed bump or the rubber posts, you've driven in the wrong place.”

Friday, January 20, 2023 in Axios

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