Accelerated incident detection and verification: A benefit to cost analysis of traffic cameras

Traffic incidents are a major contributor to congestion on US freeways, resulting in millions of dollars in property damage and significant deaths and injuries each year. Because a single incident can cause traffic delays, equally devastating secondary incidents can result. Thus, the faster an incident is detected, verified, and cleared, the less significant the impact. Traffic cameras and other technologies are widely used for this purpose. This work examined the effectiveness of traffic cameras at five metropolitan freeway sites in South Carolina using the traffic simulation software PARAMICS to simulate various incident scenarios and traffic camera operations through application programming interfaces. The authors used these interfaces to produce random spatial and temporal occurrence of incidents, including the incident start times, durations and locations. A benefit-cost analysis based on the simulation results suggested traffic cameras returned $12 for every dollar spent under the prevailing conditions at the study sites. A sensitivity study, varying different benefit- and cost-related parameters, such as deployment costs, number of incidents, and discount rate, revealed benefit-cost values that were always above one.