2018 - Research

Latent analysis of Complete Streets and traffic safety along an urban corridor

Key takeaway:

  • This research examines how built environment features (landscape, design features, traffic, vehicle and pedestrian volume) impact pedestrian, bicyclist, and driver safety and mobility. Pedestrian-friendly street interventions are necessary but not sufficient to prevent pedestrian injuries and fatalities.

Results:

  • There are two distinct classes of intersections based on environmental features: Class 1 and Class 2.
  • Class 2 intersections are more “Complete,” with pedestrian-friendly features and associated with higher pedestrian volumes. They have greater sources of potential conflict and injuries for all modes of transport, but wasn’t predictive of higher pedestrian injuries/fatalities.
  • Along a single corridor, crashes resulting in greater pedestrian injuries/fatalities were more significantly associated with alcohol use than intersection class.
  • Qualities of Cass 2 intersections include: a higher number of bus stops (which may be acting as a proxy for activity – Bus stops tend to be located at places with more pedestrian and auto volumes), more left turn lanes (which correspond to busier intersections with more complex interactions), longer crossing times (which means all road users are exposed to potential conflict with vehicles for longer while crossing), and significantly more pedestrian-friendly features (i.e., crosswalks, accessible curb ramps, traffic signals, etc.).
  • Class 2 intersections likely have more pedestrian-friendly features to mitigate pedestrian danger, since they are typically busier, complex intersections.
  • However, these pedestrian-friendly features are not enough to prevent pedestrian fatalities. Additional safety improvements are necessary.  

 

Implications:

  • Complete Streets and Vision Zero go hand in hand. Increasing safety for all road users, particularly vulnerable ones (pedestrians and bicyclists), requires not only engineering interventions in the built environment, but also educational and promotional campaigns to address people’s perceptions and attitudes.

 

Methods:

  • The researchers conducted a cross-sectional environmental audit of a five-mile urban corridor in Los Angeles in 2012. 

MacLeod, K.E.; Sanders, R.L.; Griffin, A.; Cooper, J.F.; and Ragland, D.R. (2017). Latent analysis of Complete Streets and traffic safety along an urban corridor. Journal of Transport & Health, Article in press.