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Evaluation and Refinement of Minnesota Queue Warning Systems

Status:  Complete
Report Date:  06/01/2023


Vehicles coming to a standstill, or queueing, on a highway can cause hard braking. Similarly, shockwaves that are created when traffic speeds change quickly can cause a cascade of braking. These conditions create risks for rear-end and other crashes. Warning systems use real-time traffic data, vehicle sensors and algorithms that trigger traffic warnings on overhead message boards to alert drivers to conditions ahead. A queue warning system was previously installed on a crash-prone segment of I-94. Capitalizing on two years of data, researchers evaluated system performance and found crashes decreased 56% and near-crashes decreased 69%. The system, which is integrated with MnDOT’s existing traffic management technology, was then installed in a second location upstream from the original site. Devising a data-driven methodology to evaluate the newly placed system, researchers determined that the system is transferable to other locations, though additional calibration and fine-tuning may be needed.

Final Deliverables:

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