Two-Lane Roundabouts Bring Benefits But Also Some Confusion

This article describes two-lane roundabouts, being implemented in many intersections which have enough traffic flow to require more than single-lane roundabouts. The author reminds readers that roundabouts results in increased safety because traffic must slow down to navigate the tight circle and the most dangerous types of intersection crashes (right-angle, head-on collisions) are eliminated in roundabouts. The author then reports on a study conducted by the Insurance Institute for Highway Safety (IIHS) on the effects of two-lane roundabouts. Researchers looked at crash rates, traffic movement, fuel consumption, and vehicle emissions at two intersections, both in Bellingham, Washington, before and after their conversion to roundabouts. The rates of injury crashes fell after the roundabouts were built and there were improvements in most measures of traffic flow, as well as related reductions in fuel consumption and vehicle emissions. However, the rates of crashes with only property damage increased after the roundabouts were implemented. The researchers hypothesize that these results may be due to driver confusion about right-of-way rules. Readers are referred to the full study, available from (W. Hu, et al).


  • English

Media Info

  • Media Type: Print
  • Features: Figures;
  • Pagination: pp 6-7
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 01492162
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 22 2013 8:31PM