Report: Narrow Traffic Lanes Improve Safety

Narrowing lanes can improve road safety and reclaim space for other uses.

1 minute read

November 13, 2023, 8:00 AM PST

By Diana Ionescu @aworkoffiction


New York City street with painted bike lane and crosswalk flanked by brick buildings.

Nick Starichenko / Adobe Stock

A new report from the Johns Hopkins School of Public Health concludes that narrower traffic lanes improve road safety. According to the report, “One major finding is that roads with 10–12-foot lanes at 30-35 mph speed limits have a significantly higher number of crashes compared to those with 9-foot lanes. Narrowing lane widths at these speeds provides city leaders with an opportunity to improve safety for all roadway users.”

Other key findings show that lane width affected safety on roads with speeds over 30 miles per hour and that narrower lanes “accommodate more users in less space, use less asphalt pavement, with less land consumption and smaller impervious surface areas.”

According to the report, “We found that the best candidates for lane width reduction projects are streets with 11–13-foot lanes in urban areas with speeds of 20-35 mph, as long as they are not used for heavy freight or transit.” The report recommends setting context-appropriate speed limits, factoring in pedestrians and other road users in planning decisions, setting a narrower lane standard, and using the extra space from lane narrowing for bike lanes or sidewalks.

Thursday, November 9, 2023 in Johns Hopkins Bloomberg School of Public Health

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