Road Diet Informational Guide

A classic Road Diet converts an existing four-lane undivided roadway segment to a three-lane segment consisting of two through lanes and a center two-way left turn lane (TWLTL). A Road Diet improves safety by including a protected left-turn lane for mid-block left-turning motorists, reducing crossing distance for pedestrians, and reducing travel speeds that decrease crash severity. Additionally, the Road Diet provides an opportunity to allocate excess roadway width to other purposes, including bicycle lanes, on-street parking, or transit stops. This Informational Guide includes safety, operational, and quality of life considerations from research and practice, and guides readers through the decision-making process to determine if Road Diets are a good fit for a certain corridor. It also provides design guidance and encourages post-implementation evaluation.

  • Record URL:
  • Corporate Authors:


    11251 Roger Bacon Drive
    Reston, VA  United States  20190

    Federal Highway Administration

    Office of Safety, 1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Knapp, Keith
    • Chandler, Brian
    • Atkinson, Jennifer
    • Welch, Thomas
    • Rigdon, Heather
    • Retting, Richard
    • Meekins, Stacey
    • Widstrand, Eric
    • Porter, R J
  • Publication Date: 2014-11


  • English

Media Info

  • Media Type: Digital/other
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 72p

Subject/Index Terms

Filing Info

  • Accession Number: 01563670
  • Record Type: Publication
  • Report/Paper Numbers: FHWA-SA-14-028
  • Contract Numbers: DTFH61-10-D-00024, Task Order No. T-12-004
  • Created Date: May 6 2015 11:28AM