Before and After Safety Evaluation of California’s and San Diego's Active Transportation Projects

California, and the San Diego region in particular, have invested in pedestrian and bike improvements, including sidewalks, protected cycletracks, bike lanes, protected intersections, and other infrastructure improvements to enhance the user experience and promote safety. However, despite the efforts to improve infrastructure, collisions involving pedestrians and cyclists and persistently low active travel mode share remain significant concerns. The existing literature suggests that the presence and quality of bicycle infrastructure play a crucial role in improving perceived safety among riders and reducing collision rates (Ferenchak & Marshall; Buehler and Pucher, 2020; Fosgerau et al, 2023; Reynolds et al., 2009; Kaths, 2022; Steinacker et al., 2022; Wysling & Purves, 2022). Previous research that specifically examines the effects of pedestrian and bicycle-friendly infrastructure on crash and injury rates have shown mixed results. For example, longitudinal studies on the Safe Routes to School (SRTS) program, which funds both infrastructure and non-infrastructure improvements for pedestrians and cyclists, found that the program reduced collisions amongst active transportation users in California and New York City (Ragland, Pande, & Bigham, 2014; Dimaggio & Li, 2013). However, another SRTS study focused on New York State did not find significant declines in collisions resulting from the program (Kang et al, 2020). In some cases, implementation of bicycle infrastructure caused vehicle-bicycle collisions to increase, but researchers hypothesized that this increase occurred because more cyclists were present on streets with improved bicycle infrastructure (Pedroso et al, 2016; Chen et al, 2012). California and the San Diego region lacks comprehensive research on both usage and collision rates associated with investments in pedestrian and bicycle infrastructure, which limits understanding of their effectiveness and impact. Quasi experimental studies using pre/post data surrounding new project implementation is particularly lacking. While the implementation of such projects has received widespread support, there is a need to critically examine their benefits, including bike and pedestrian trips, safety and the reduction of the collision rates throughout California and the San Diego region.


  • English


  • Status: Active
  • Funding: $180807
  • Contract Numbers:


  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    Center for Pedestrian and Bicyclist Safety

    University of New Mexico
    Albuquerque, NM  United States  87131
  • Performing Organizations:

    San Diego State University

    5500 Campanile Dr
    San Diego, CA  United States  92182
  • Principal Investigators:

    Appleyard, Bruce

  • Start Date: 20230601
  • Expected Completion Date: 20240531
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers Program

Subject/Index Terms

Filing Info

  • Accession Number: 01890845
  • Record Type: Research project
  • Source Agency: Center for Pedestrian and Bicyclist Safety
  • Contract Numbers: 69A3552348336
  • Files: UTC, RIP
  • Created Date: Aug 23 2023 8:49PM