Transportation Benefits and Costs of Reducing Lane Widths on Urban and Rural Arterials

Details

• Creators:
  Ewing, Reid ; Promy, Noshin Siara ; Choi, Dong-ah ; Yang, Wookjae ; Tabassum, Nawshin ; Kaniewska, Justyna ; Ameli, Hassan ; Tuffour, Justice Prosper ; Kalantari, Hannah A ; Azin, Bahar ; Yang, Xianfeng (Terry)
• Corporate Creators:
  University of Utah. Department of City and Metropolitan Planning
• Corporate Contributors:
  Utah. Department of Transportation ; Utah Transit Authority
• Subject/TRT Terms:
  Benefit Cost Analysis Highway Capacity Highway Design Highway Safety Traffic Lanes Width
• Publication/ Report Number:
  UT-24.03
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Edition:
  Final Report; 2022-2024
• Corporate Publisher:
  Utah. Department of Transportation
• Abstract:
  Reducing the lane width of urban arterials provides space for different street features, whereas selecting the appropriate lane width considering road safety is a concern. The major elements of this research are: a comprehensive literature review investigating the effects narrower travel lanes and other geometric designs have on speed, safety, and other transportation impacts; an in-depth survey of the minimum lane width policies and practices adopted by four leading state DOTs; a survey of AASHTO Committee on Design members regarding their policies and practices, and statistical analyses on speed and crash factors. The authors conducted interviews with five DOTs, and the interviews included queries regarding design criteria, design exceptions, and completed projects or future projects on urban and suburban roadways involving lane width reduction. The findings from the interviews suggest that reducing lane widths contributes to reducing speed and accommodates other modes. However, lane width reductions need to be combined with other low-speed strategies, such as traffic calming and lane repurposing. Enabling integrated walking, biking, transit, and passenger rail can mitigate speed and crash rates. Data from 320 urban and 61 rural arterial sections in Utah were assembled for statistical analysis. Safety modeling showed no direct relation between lane width and crash counts per mile in both areas. However, urban injury crashes are linked to lane width and speed, wider lanes, and higher speeds for increasing injury likelihood. Factors for crash counts were lanes and AADT per lane. This study supports reducing lane widths to enhance road safety and urban transportation infrastructure. Decision makers can use these findings to improve road safety and performance.
• Format:
  PDF
• Funding:
  22-8095
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:e5f5a27470cb57d8095be60f95765555f9f8ec9506a673efb55077e3cbe05c10a1cfbbf9cbc3128461887e7bc2c2febf248d6f0c2e4241fdc2c1050e649e432d
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/74632/dot_74632_DS1.pdf
• File Type:
  [PDF - 5.34 MB ]