ASSESSING THE IMPACTS OF THE DYNAMIC EARLY LANE MERGE TRAFFIC CONTROL SYSTEM

This paper describes how the dynamic early merge traffic control system (EMTCS) has been implemented in work zones with lane closures in Michigan over the past few construction seasons. This system consists of dynamic Do Not Pass/When Flashing sign trailers that are equipped with detectors to capture speed, volume and lane occupancy data at the detection zone. A series of five signs dynamically communicate with one another to create a variable no passing zone, by activating the signs on and off flashing mode, based on the detected traffic volume and occupancies. The Michigan Department of Transportation implemented this system to mitigate the forced lane merges and aggressive driver behavior typically observed at lane closures in highway work zones. The authors of this paper were involved in the refinement of the system layout and settings, as well as the evaluation of the system in terms of improving safety and operations in work zones. Initially this system was tested on highways with two lanes in each direction, reduced to one lane at the lane transition area, however recently the dynamic ELMTCS is being tested on highway with three-lanes in each direction reduced to two lanes during construction. A six-month long 'before and after' study at a two-lane to one-lane suburban freeway work zone in Michigan has been completed. The results of this analysis indicated significant reductions in aggressive driver behavior, lane violations and delay, as well as a slight improvement in traffic flow. The results of an economic analysis demonstrated that based on the operational benefits alone, the dynamic ELMTCS was cost effective at the site tested.