Date of this Version
Chang, Wonsun. (2019) The relationship between separated bicycle lanes and bicycle crashes in Denver, Colorado
Cyclists feel more comfortable when they ride in a bike facility separated from traffic. Therefore, cyclists tend to prefer separated bicycle lanes over other lanes. It follows that cities are increasing the installation of separated bicycle lanes for bicycle utilization and bicycle safety. However, previous research has proven that separated bicycle lanes cause more crashes. Through empirical study, this paper examined the impact of both separated bicycle facilities and shared roads on bicycle crashes and which is safer or dangerous among methods of the separation. This study deals with bicycle accidents in Denver from 2013 to 2019. This research creates bicycle crash data by extracting only bicycles involved in the crash from the traffic accident dataset. And then, using the ArcGIS tool, the bicycle crash spatial is joined to each bicycle facility segment. Therefore, this study generated dataset of a bicycle crashes based on bike facilities. In the next step, a Poisson Rate Regression analysis was conducted in this study (run in SAS 9.4). The result is that a separated bike lane is estimated to increase the average number of crashes by 117% compared to a shared road. The second result showed that a cycle track facility is estimated to increase the average number of crashes 401% compared to a bike lane facility. In conclusion, a separated bicycle facility has more crashes than a shared road. Among separated bicycle facilities, a cycle track, where physically separated facilities were installed, was most likely to cause crashes.
Advisor: Yunwoo Nam