In Pursuit of Safety: Systemic Bicycle Crash Analysis in Seattle, WA
This study aimed to use robust methods to identify and prioritize locations at risk for future bicycle crashes and injuries, to broaden treatment priorities beyond only high crash locations. Using data from Seattle, WA, the authors developed safety performance function (SPF) models for three high-frequency and/or high-severity bicycle intersection crash types: total bicycle crashes at intersections, crashes in which the bicyclist and driver were traveling in opposite directions, and crashes in which the bicyclist and driver were traveling perpendicularly to one another. We tested a large number of variables, and found a number of measures of pedestrian and bicycle activity, roadway, and other built environment measures aided bicycle crash prediction. Several variables that represented intersection complexity and may have been proxies for AADT were significant in all three models, including arterial classification, larger numbers of lanes, and two- way center turn lanes. Interestingly, pedestrian volume exhibited a curved relationship to crashes, demonstrating a potential safety benefit to cyclists from increased pedestrian activity. The SPFs were used in several ranking methods, including SPF-predicted crashes, empirical- Bayes (EB)-estimated crashes, and Potential for Safety Improvement (PSI, excess crashes) to aid in prioritization of locations that might be candidates for safety improvement. These analyses and associated ranking methods provide a means of prioritizing locations based on model predictions, and are important tools to consider for jurisdictions that wish to take a more proactive approach, in addition to traditional hotspot or frequency-based approaches, to reduce the potential for future crashes and injuries.
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Supplemental Notes:
- This paper was sponsored by TRB committee ANB20 Standing Committee on Safety Data, Analysis and Evaluation. Alternate title: In Pursuit of Safety: Systemic Bicycle Crash Analysis in Seattle, Washington
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Corporate Authors:
500 Fifth Street, NW
Washington, DC United States 20001 -
Authors:
- Thomas, Libby
- Lan, Bo
- Sanders, Rebecca
- Frackelton, Alexandra
- Gardner, Spencer
- Hintze, Michael
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Conference:
- Transportation Research Board 96th Annual Meeting
- Location: Washington DC, United States
- Date: 2017-1-8 to 2017-1-12
- Date: 2017
Language
- English
Media Info
- Media Type: Digital/other
- Features: Maps; References; Tables;
- Pagination: 22p
- Monograph Title: TRB 96th Annual Meeting Compendium of Papers
Subject/Index Terms
- TRT Terms: Bicycle crashes; Crash risk forecasting; Injuries; Intersections; Traffic volume
- Geographic Terms: Seattle (Washington)
- Subject Areas: Pedestrians and Bicyclists; Safety and Human Factors;
Filing Info
- Accession Number: 01624847
- Record Type: Publication
- Report/Paper Numbers: 17-06840
- Files: TRIS, TRB, ATRI
- Created Date: Feb 1 2017 5:14PM