Congestion Management System

Executive Summary

A Congestion Management System (CMS) is a requirement of the transportation planning process for Metropolitan Planning Organizations that have greater than 200,000 population. The primary function of a CMS is to develop a systematic and consistent process for identifying locations of congestion on the multi-modal transportation system, and to identify and evaluate potential actions that can effectively reduce congestion.

A CMS must be tailored to the specific characteristics of the region it is to be implemented, and therefore the Knoxville Regional Transportation Planning Organization (TPO) developed a CMS that addresses roadway congestion since personal vehicle travel is currently the predominant transportation mode locally. The CMS evaluated all roadways with an average daily traffic amount of 10,000 vehicles per day or greater against two basic performance measures – volume-to-capacity ratio and travel time to determine the level of mobility on each. The result of the performance measure analysis was a list of congested roadway corridors and congestion “hot-spot” locations.

A set of congestion mitigation strategies was developed and evaluated for applicability to each of the congested locations that were identified. The congestion mitigation strategies were developed according to guidance in the federal CMS-enacting legislation, which places an emphasis on reducing the number of automobile trips and improving management of roadway operations rather than expanding supply, such as roadway widening. Strategies that promote ridesharing and alternative forms of transportation to the personal vehicle are the preferred means of managing congestion when proven to be effective. Other cost-effective congestion mitigation strategies include maximizing the efficiency of the existing roadway system through optimized traffic signal timing, or application of Intelligent Transportation Systems (ITS) technologies to enhance incident response and traveler information. It is recognized, however, that certain corridors will require additional capacity to be built in order to meet traffic demand at an acceptable level-of-service for the roadway user.

The information from the CMS can be used to support the project selection processes of future Long Range Transportation Plans and Transportation Improvement Programs. It should be noted however that the CMS is not intended to supercede other elements of the planning process, nor is it intended to prioritize all transportation projects. The primary purpose of the CMS is to provide for a more informed decision-making process that will be used to make the most effective and efficient use of limited resources to address congestion problems.