Identifying Methods and Metrics for Evaluating Interagency Coordination in Traffic Incident Management

One role of state departments of transportation (DOTs) is traffic incident management (TIM): managing incidents that impact traffic flow on interstate highways and involve multiple agencies (e.g., police, fire). This study found DOTs collect basic TIM performance measures (e.g., lane clearance times), but many do not record additional measures, consistently review the collected data, or analyze it unless needed to answer specific questions. Since performance evaluation of interagency coordination is one area of TIM in which little success has been attained (FHWA, 2003), process improvement methods from operations management may prove useful. To illustrate, interagency incident response for a disabled vehicle (no injuries or property damage) is modeled as a process in which appropriate resources (e.g., state police, tow) must coordinate to safely remove the vehicle and restore normal traffic flow. Completing these events requires the resources to perform specific functions, each taking more or less time depending on various factors (e.g., weather, time of day). Response time data can highlight geographic areas or process segments with highly variable event times, leading to investigation and recommendations to reduce variability and, ultimately, traffic delays. Based on this approach, recommendations are made for data collection and analysis of appropriate TIM performance measures.