Trade-offs for Cross-sectional Reallocation on Urban and Suburban Roads

The allocation of space within a roadway cross-section allows for the movement of people and freight. Designs for urban and suburban roadways should balance operational and safety performance among multiple transportation modes, while meeting a variety of societal goals such as social equity, economic vitality, public health, and environmental stewardship. Design guidance exists for individual elements within a roadway, such as travel lanes, on-street parking, medians, and bicycle, pedestrian, and transit facilities. However, current design guidance does not reflect the complex and varied trade-offs transportation professionals consider for existing roadways in different contexts. Many transportation agencies have reallocated roadway space through resurfacing and reconstruction projects within existing right-of-way. These projects can provide cost-effective opportunities to improve safety and develop multimodal networks. A common roadway space reallocation converts a four-lane undivided road to a three-lane road that includes bicycle lanes and a two-way left turn lane. Research has shown this to be an effective design approach. Less research has been done on the benefits of other configurations for roadway space reallocation. Since there are positive and negative effects associated with different roadway configurations, designers should consider the potential outcomes for all users and assess trade-offs. However, there is limited context-based guidance available to practitioners on how to evaluate trade-offs in cross-sectional reallocation of existing urban and suburban roadway space. The objective of this research is to develop a guidebook and decision-making framework for roadway designers, planners, and others for identifying, comparing, evaluating, and justifying context-based cross-sectional reallocations of existing urban and suburban roadway space for multimodal safety, access, and mobility. The guidebook should: (1) Identify the range of multimodal cross-sectional design elements, their potential context applications, their interactions, and their potential impacts on the transportation network. (2) Present quantitative and qualitative measures that address multimodal performance of alternative roadway cross sections. (3) Identify or develop methods for predicting outcomes such as mode shift, safety performance, and social, economic, and environmental consequences. (4) Present mitigation strategies for addressing potential negative outcomes. (5) Identify barriers to implementation and strategies to overcome the barriers. (6) Present key messages and techniques to effectively communicate information on the benefits and trade-offs to stakeholders. (7) Identify gaps in the state-of-the-practice knowledge that may be attributable to insufficient data and experience that may be addressed in future research.


  • English


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

    Project 15-78

  • Sponsor Organizations:

    National Cooperative Highway Research Program

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

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Project Managers:

    Schwager, Dianne

  • Start Date: 20200515
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01707670
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 15-78
  • Files: TRB, RiP
  • Created Date: Jun 3 2019 3:17PM