Framework for Estimating the Impact of Camera-Based Intelligent Transportation Systems (ITS) Technology on Incident Duration

Safety is a major motivator of intelligent transportation systems (ITS) projects, and most efforts have addressed the potential to avoid incidents. Managing and reducing the duration of incidents is another key application for ITS despite challenges in distinguishing the true versus the reported duration of an incident. This paper presents a framework for modeling the impact of camera-based (closed-circuit television or CCTV) ITS technology on incident duration including an increase in the reported duration and a reduction in the true duration. The framework is validated against a data set of 121,793 accidents in New South Wales, Australia, covering 4.5 years. The results demonstrate that the use of CCTVs for incident duration contributes a 4.5 min reduction in average duration (as earlier detection can lead to more efficient clearance) and a 9% reduction in variance in the duration (as a uniform detection method supports standardized response procedures). These impacts are only visible when the 8.5 min median detection delay (the difference between the recorded duration and the true duration) is modeled and accounted for. These results offer a quantitative support tool for decision makers wishing to assess the value of incident-detection ITS projects.