Evaluation of Freeway Incident Management Based on Toll Station Data in China

In 2007, the Operation and Scheduling System (OSS) (including freeway incident management) was set in the Ningtong freeways in Jiangsu Province of China. An approach developed to evaluate the benefits of certain incident management system programs (based on the characteristic that toll stations stand in almost every access and entrance and consist of a close and integrate freeway net in China) was proposed. With toll station data (mainly for calculating the incident delay) and incident logs (mainly for inquiring the incident duration), delay saving can be calculated by extending or reducing the incident duration using queuing theory. With this data, the saved fuel cost, amount of emission reduction, reduced travel time, and reduced secondary incidents can be calculated. After almost one year, real incident data after the construction of the OSS program in the Ningtong freeway were tested and a range of benefit-cost ratios from 3.7:1 to 12.7:1 was calculated. This result indicates that the OSS is a cost-effective tool for freeway incident management.