National Investigation of the Environmental, Safety and Livability Impacts of Travel Lane Width: Evidence from 10 American Cities

This project is one of the most comprehensive efforts to date to address a long overdue built environmental and transportation challenge to health: unnecessarily wide travel lanes that are designed to accommodate fast and convenient driving. There has been a constant competition for space in roadways’ right-of-way. In most American cities, the automobile is the winner of this competition, making it a challenge to find space for bike lanes and sidewalks. One of the easiest and most cost-efficient way to make space for cyclists and pedestrian is to narrow travel lanes and parking lanes to an optimal width. The main drawback is safety concerns. Are wider lanes safer? A recent study in seven US Cities by the PI found that narrower lanes do not have a higher number of crashes than their wider counterparts, after controlling for 21 functional and design street characteristics. This study builds on the earlier effort by (1) expanding sample to more than 1,500 street sections with three additional cities and measuring a comprehensive set of 21 micro-scale street design features for these streets; (2) quantifying the impact of narrow travel lane on traffic fatalities, pedestrian safety, and bicycle safety indicators; and (3) measuring the impact of narrow lane width on pedestrian volume and activities. Finally, from the national sample of ten cities, the PIs will select one lane width reduction project for further longitudinal analysis of traffic speed, roadway capacity (traffic volume), roadway safety (crash severity and frequency) and GHG emission impacts before and after the lane width reduction.

• Record URL:
  https://publichealth.jhu.edu/center-for-climate-smart-transportation/research-lane-width

Language

• English

Project

• Status: Active
• Funding: $244163
• Contract Numbers:

  DOT 69A3552348325

  Task Order: CCST-2023-11

• Sponsor Organizations:

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590

  Center for Climate-Smart Transportation

  615 N Wolfe St
  Baltimore, Maryland  United States  21205

  Bloomberg American Health Initiative

  615 N Wolfe St
  Baltimore, Maryland  United States  21205
• Managing Organizations:

  Center for Climate-Smart Transportation

  615 N Wolfe St
  Baltimore, Maryland  United States  21205

  Johns Hopkins University, Baltimore

  Baltimore, MD  United States 
• Project Managers:

  Kline, Robin

• Performing Organizations:

  Center for Climate-Smart Transportation

  615 N Wolfe St
  Baltimore, Maryland  United States  21205

  Johns Hopkins University, Baltimore

  Baltimore, MD  United States 
• Principal Investigators:

  Hamidi, Shima

  Azimi, Ebrahim

• Start Date: 20231001
• Expected Completion Date: 20240930
• Actual Completion Date: 0
• USDOT Program: University Transportation Centers

Subject/Index Terms

• TRT Terms: Cities; Complete streets; Cyclists; Environmental impacts; Greenhouse gases; Highway capacity; Highway safety; Livability; Pedestrian safety; Traffic lanes; Width
• Subject Areas: Design; Environment; Highways; Pedestrians and Bicyclists; Policy; Safety and Human Factors;

Filing Info

• Accession Number: 01906724
• Record Type: Research project
• Source Agency: Center for Climate-Smart Transportation
• Contract Numbers: DOT 69A3552348325, Task Order: CCST-2023-11
• Files: UTC, RIP
• Created Date: Feb 1 2024 10:04AM