Evaluation and Refinement of Minnesota Queue Warning Systems

The formation and propagation of queues on urban freeways is an unavoidable result of the ever-increasing traffic demand. Besides the congestion increase and efficiency reduction in the transportation network system, some of these queues can cause serious rear-end collisions, resulting in property damages and injuries. The queue warning system (MN-QWARN), targeting shockwaves and traffic at the initial stage of breakdown, deployed on I-94 WB has been in operation for more than a year and the initial three-month evaluation period afforded suggested a crash reduction of more than 20%. The proposed project has the following objectives: (1) Expand the evaluation of both deployed systems, using all available historical data since their initial deployment day. This includes video records as well as crash reports. (2) Implement the refinements already developed for the MN-QWARN system and initiate a new evaluation period. (3) Evaluate the transferability of the MN-QWARN system by implementing it in two locations upstream of its current deployment. This will also serve as a crash reduction system during the I-35W/I-94 reconstruction project second year, which will be in full force starting April 2018. (4) Expand the MN-QWARN system implementation to use Wavetronix sensors, which are the new MnDOT preferred sensors. (5) Estimate the cost/benefit structure of the queue warning systems to assist in future deployments.