Diversion of traffic to an alternative route during a major freeway incident seems to be an effective traffic management practice to reduce travel delay and potential secondary accidents. Informed traffic diversion to an alternative route can provide positive psychological impacts on motorists. The question is whether it can actually save travel time of motorists by using an alternative route. The magnitude of motorists' benefits as well as the factors affecting the travel time on alternative routes have not been clearly examined or documented. This study conducted actual traffic simulations to compare travel times between an established alternative route and the freeway with a major incident through a case study in Sarasota, Florida. A license plate matching technique was adopted to obtain the travel times of sample vehicles in the traffic simulation. This study examined the impacts of traffic conditions, signal timing strategies, incident duration, and the timing regard for the implementation of informed traffic diversion on average network delay and individual travel time. It identified the requirements for operating a safe and effective alternative route. The simulation results from the case study provide the magnitude of motorists' benefits on travel time by using an alternative route. The results also verify the value of alternative route operations in response to a major freeway incident.
Abstract