Pedestrian safety is a priority of the Washington State Department of Transportation’s (WSDOT) Target Zero Plan. However, even though crash fatalities have decreased for motor vehicles in Washington state, pedestrian fatalities have remained relatively steady. To help WSDOT prioritize safety-related pedestrian projects, this study used data from a variety of sources to develop pedestrian risk models that identify urban and suburban locations that are at most risk for pedestrian crashes throughout the WSDOT roadway network.
The researchers developed pedestrian risk models that can be used to identify the characteristics that contribute to pedestrian crashes that result in severe injuries and fatalities and the locations that are most likely to benefit from investments aimed at zero pedestrian fatalities and zero serious injuries.
The development of these tools was based on available data sources, including WSDOT, the Census, the King County GIS Center, the University of Washington Urban Form Lab, and National Historical Geographic Information. The results were frequency models that identified factors and locations in Washington state that are associated with a higher rate of pedestrian-motor vehicle crashes and severity models that identified factors that contribute to pedestrian crashes that result in serious injuries and fatalities.
The frequency models looked at the number of pedestrian-motor vehicle crashes per 100-meter buffer around intersection and non-intersection locations on state routes in King County, Washington, and for all of Washington state. Crash-prone locations and micro-environment variables significantly associated with the pedestrian crash rate included a greater number of roadway lanes, higher density of transit ridership, higher residential and employment densities, the presence of park and ride facilities, and areas of lower income. Differences between the intersection and non-intersection models indicated that different pedestrian safety strategies might be used for each type of location.
The injury severity models examined the likelihood of pedestrian-motor vehicle crashes resulting in serious injuries or fatalities. At crash locations, pedestrians ages 45 and above were found to have a greater likelihood of sustaining fatal or serious injuries than pedestrians ages 25 to 44. The likelihood of serious injuries or fatalities was found to increase when pedestrians failed to grant the right of way to vehicles, when the driver was moving straight ahead, and in lower light conditions. Information missing from police crash reports on vehicle speeds and the actions of pedestrians and drivers at the time of a crash underscored the importance of gathering accurate and complete information at the time of a crash.
The outcomes of this project should inform WSDOT’s operational programs and help the agency prioritize safety-related pedestrian projects.
Authors:
Linda Ng Boyle, UW Department of Civil and Environmental Engineering
Anne Vernez Moudon, UW Department of Urban Design and Planning
Haena Kim, UW Department of Civil and Environmental Engineering
Mingyu Kang, UW Department of Urban Design and Planning
Sponsor: WSDOT
WSDOT Technical Monitor: Mike Dornfeld
WSDOT Program Manager: Jon Peterson