Integrated Corridor Management (ICM) systems are a promising approach for managing both travel demand and network demand in normal and abnormal conditions. Traditionally, ICM is applied in an urban setting where multiple transportation modes are readily available. However, the North Carolina Department of Transportation (NCDOT) has applied ICM principles in more rural applications where fewer modal and network options are likely to exist. NCDOT has deployed ICM on 22 miles of I-85 from Mile Marker 10 to 32 near Charlotte, with a focus on managing incident-related congestion on the interstate and parallel US-74 arterial. This deployment includes traveler information on Dynamic Message Signs, activatable detour trailblazer signs for individual incidents, and incident-specific signal timing plans for intersections included in the detours.
To accurately capture the traffic diverted due to ICM activations, observations of traffic flow patterns are essential. In this project, Bluetooth and Wi-Fi traffic monitoring devices were placed throughout the corridor and used to match trips along the primary and detour routes to establish baseline Origin-Destination (O-D) patterns which can be compared to ICM activations after implementation. This project also adapted an existing sketch-planning NCDOT analysis method used in the project prioritization process to compare estimated delays on primary and detour routes during ICM operation. The inputs for diversion rates and capacity benefits from ICM-specific signal timing can be updated as observations provide better estimates.
To support the monitoring and evaluation of the ICM deployment, this project developed a dashboard integrating data feeds from public and private sources and an evaluation framework that captures delay, safety, environmental, administrative, and capital impacts of ICM deployment. The implementation of the developed framework showed significant benefits to the project stakeholders, particularly in cases of high incident severity. The benefits are dependent on both the severity of the incident and the time of day, with peak periods yielding greater benefits compared to non-peak periods. The overall benefit of ICM implementation was found to be substantial. Additionally, the analysis of the 5-year and 10-year benefit-cost ratios of the I-85 ICM program indicated that the investment in ICM is likely to result in a favorable return on investment over a period of 5 and 10 years.
