Design Options to Reduce Turning Motor Vehicle – Bicycle Conflicts at Controlled Intersections

One of the most common locations for fatal motor vehicle-bicyclist crashes is at intersections, which inherently have a large number of turning conflicts. Reducing these conflicts is a key objective in improving intersection safety across all modes. Of particular concern for bicyclists’ safety at intersections are the conflicts between straight-through bicyclists and motor vehicle right-turns and opposing left-turns. Despite the widespread acknowledgement of this problem, transportation engineers and planners still lack definitive guidance on how to safely and effectively design for bicyclists at intersections in the United States. Design practices that drop bicycle pavement markings and signs at intersections, providing no positioning guidance for motorists or bicyclists, can lead to confusion over who has the right-of-way through the intersection. Some jurisdictions continue bicycle lane markings all the way through intersections; in others, the lanes are dashed. Moreover, the use of a variety of innovative treatments including bike boxes, use of color, bicycle signals, and separated crossings is increasing across the country; while some of these have been examined through research studies, with some promising results, the results are inconclusive. Research is needed to identify design best practices to reduce conflicts at intersections. The objective of this research was to develop guidance and tools for transportation practitioners to use to reduce turning conflicts between motor vehicles and bicycles at controlled intersections.


  • English


  • Status: Completed
  • Funding: $600000
  • Contract Numbers:

    Project 15-73

  • Sponsor Organizations:

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Retting, Richard

  • Performing Organizations:

    Toole Design Group

  • Principal Investigators:

    Fink, Christina

  • Start Date: 20201002
  • Expected Completion Date: 20240603
  • Actual Completion Date: 20240603

Subject/Index Terms

Filing Info

  • Accession Number: 01707631
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 15-73
  • Files: TRB, RIP
  • Created Date: Jun 6 2019 5:24PM