Synthesis of Information Related to Highway Practices. Topic 50-11. Alternative Intersection Design and Selection

Final Scope Alternative intersection designs continue to grow as viable options at a variety of area and facility types across the United States. Alternative intersections are created by rerouting one or more movements to remove major conflict points. Agencies use a variety of terms for alternative intersections. Examples include J-turns, continuous flow intersections, median U-turns, and diverging diamond interchanges. By removing conflict points at major intersections, alternative intersections have proved to offer greater safety and operational benefits when compared to conventional intersection design. The objective of this synthesis is to document the evaluation and selection process within departments of transportation (DOTs) for intersection projects. The synthesis will document the critical factors in making alternative intersection design decisions, including design criteria, illumination requirements, traffic control devices, pedestrian, bike, and truck considerations, and right-of-way requirements. The focus will be on at-grade intersections as well as intersections at interchange ramp terminals. Roundabouts will be included in the assessment of evaluation processes with respect to other alternative intersection options, but the synthesis will not address roundabout specific design criteria. Information to be gathered includes (but is not limited to); • Assessment and evaluation tools (e.g., CAP-X, SPICE, state specific tools such as those used by Virginia, Pennsylvania, and Florida); • Documented DOT intersection evaluation procedures, policies, and guidelines (e.g., ICE, Indiana DOT intersection decision guide); • Documented design criteria relative to alternative intersections (e.g., Utah DOT DDI guideline and CFI design guidelines, Missouri DOT EPG section on DDIs); • DOT practices and information resources for public education and outreach (e.g., website, animated drive-through videos; • Constructability and temporary traffic control; • Documentation of safety and operation benefits (excluding roundabouts); and • Barriers to implementation and strategies for overcoming those barriers. Information will be gathered through literature review, a survey of DOTs, and follow-up interviews with selected agencies for the development of case examples. Knowledge gaps and suggestions for research to address those gaps will be identified. Information Sources: • Hatem Abou-Senna, Essam Radwan, Sebastian Tabares, Jiawei Wu, & Sandesh Chalise. “Evaluating Transportation Systems Management & Operations (TSM&O) Benefits to Alternative Intersection Treatments”, Final Report, Florida Department of Transportation Research Center, December 2015. • Highway Capacity Manual, Transportation Research Board, National Research Council, Washington, D.C., 2016, Sixth Edition. • Hughes Warren, Ram Jagannathan, Dibu Sengupta, and Joe Hummer. "Alternative Intersections/Interchanges: Informational Report (AIIR)", USDOT, FHWA, Publication No. FHWA-HRT-09-060 April 2010. • Asokan, Anand, Bared, Joe G, Jagannathan, Ramanujan, Hughes, Warren, Cicu, Federico Illotta, Pier Fabrizio. “Alternative Intersections Selection Tool - AIST.” Transportation Research Board, Presentation at the 89th Annual Meeting of the Transportation Research Board, 10 Jan. 2010. • Alisa Bowen, Mike Eubank, Jason Kaiser, Dana Plattner, Greg Richards, Bill Smith, Brad Steckler, “Intersection Decision Guide”, Indiana Department of Transportation, January 14, 2014. TRB Staff Jo Allen Gause Phone: 202-334-3826 Email: Meeting Dates First Panel: October 16, 2018, Washington, DC Teleconference with Consultant: November 8, 2018, 4:00 p.m., EST Second Panel: June 27, 2019, Washington, DC Topic Panel Christina D. Barry, Georgia DOT Bradford Foley, Maine DOT Federico Gontaruk, Virginia DOT John M. Mason, Jr., Penn State Harrisburg Kenneth L. Mora, Texas DOT Brad Steckler, Indiana DOT Mike R. Wahlstedt, TranSystems Mark Doctor, Federal Highway Administration Richard A. Cunard, Transportation Research Board


  • English


  • Status: Active
  • Funding: $45000
  • Contract Numbers:

    Project 20-05, Topic 50-11

  • 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:

    Gause, Jo

  • Performing Organizations:

    University of Missouri, Columbia

    Columbia, MO  United States  65211
  • Principal Investigators:

    Brown, Henry

  • Start Date: 20181016
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01669002
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 20-05, Topic 50-11
  • Files: TRB, RiP
  • Created Date: May 14 2018 3:04PM