Speed Management Solutions and Strategies to Improve Pedestrian and Bicyclist Safety on Arterial Roadways

While the role of speed in traffic crashes is a complex topic, research has found unequivocally that higher speeds lead to higher injury severity for vulnerable road users (Sanders et al., 2019). Notably, the risk of serious injury or fatality for pedestrians increases dramatically as vehicle speed on impact increases, with a roughly 13% change of fatality or severe injury at 20 miles per hour (mph), 40% at 30 mph, and 73% at 40 mph (Tefft, 2013). It is also clear that drivers traveling at higher speeds have less time to react to unexpected situations, less recovery time if distracted, and longer braking distance, which contributes to crashes (Boodlal et al., 2015). A safe-systems approach to roadway safety requires a robust speed management effort. On lower-volume roadways, traffic-calming strategies with vertical and horizontal deflections (raised speed humps, bumps, chicanes, center turning islands) have been found to be effective at lowering speeds. However, incompatible land uses are often placed next to high-speed roadways, and solutions for traffic-speed management along arterials and higher-speed roadways are more limited and often much more challenging to implement. Research has found that higher-speed arterial roadways are associated with increased frequency and severity of pedestrian and bicycle crashes (Guerra et al., 2019; Lin et al., 2019). There is some evidence that strategies such as road lane reductions, automated speed enforcement, lane width reductions, speed limit reductions, modifications to traffic signal timing, and well-placed landscaping can reduce vehicle speeds. However, the relationship between lowering vehicle speeds and the magnitude of changes in outcomes for pedestrian and bicycle safety are less clear. Importantly, although the factors relating to the increased risk of speed to people walking will also apply to people bicycling, few studies specifically link bicyclist or pedestrian injury or fatality risk to speed management directly. In addition, research shows that more active travel lowers risk and while research generally suggests that slower motor vehicle speeds encourage more walking or cycling, there is limited research that quantifies this relationship directly. Research is needed to demonstrate the impacts of speed management efforts on higher-speed roadways, specifically for people walking and bicycling, and provide clear guidance on successful implementation strategies that have balanced lower speeds for some users with safety improvements for others. The research objective of this project is to produce a guide that can be used as a context driven roadmap to speed management on arterial and higher-speed roadways, and how this can be balanced with appropriate safety improvements for pedestrians and bicyclists on these arterial and high-speed roadways.

Language

  • English

Project

  • Status: Proposed
  • Funding: $550000
  • Contract Numbers:

    Project 17-111

  • 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:

    Deng, Zuxuan

  • Start Date: 20220607
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01847456
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 17-111
  • Files: TRB, RIP
  • Created Date: May 23 2022 3:02PM