The objective of Committee 5P-5A was to investigate the capacities of triple left-turn lanes and correlate the findings with roadway geometric features. Results of this study indicate an overall saturation flow rate for triple left-turn lanes of approximately 1,830 pcphgpl. Results also indicate that there may be no significant difference in the saturation flow rates between each of the three left-turn lanes, or between any of the turn lanes and the adjacent through lane. The lack of evidence in this study concerning any significant relationships between intersection geometry and triple left-turn lane saturation flow rates may be attributable, in part, to the effects of downstream attraction bias. This may cause drivers to preposition themselves in the turn lane most favorable to their immediate downstream destination.

  • Supplemental Notes:
    • Prepared by ITE Technical Council Committee 5P-5A.
  • Corporate Authors:

    Institute of Transportation Engineers (ITE)

    Washington, DC  United States 
  • Authors:
    • Stokes, R W
  • Publication Date: 1995-4


  • English

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 19 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00723572
  • Record Type: Publication
  • Report/Paper Numbers: IR-077
  • Files: TRIS
  • Created Date: Jul 22 1996 12:00AM