Ice on roadways is a significant concern for a state that experiences below-freezing temperatures for the better part of three months. Even the most experienced drivers can be caught off-guard when traveling over black ice, through freezing rain, and on snow-packed roadways.
MnDOT District 8 maintenance staff identified a small section of US Highway 12 near the City of Cokato as an area which commonly experiences a condition locally known as “blow ice”. Due to the rural nature and roadway elevation of the area, ice forms when snow blows across the highway, creating an unexpected sheet of ice for travelers. Over the years, this “blow ice” phenomena has caused numerous accidents, many of which involve high school students traveling to and from Dassel/Cokato High School. MnDOT had previously implemented other solutions including living and traditional snow fences with marginal success.
With the assistance of MnDOT’s Office of Traffic, Safety and Technology ITS staff a project was initiated to develop an innovative technology based solution to this problem. SRF Consulting Group, Inc. was selected to develop a Concept of Operations and System Requirements document that reflected stakeholder input for the proposed ITS solution. Based on these documents, a system was designed with three in-pavement ice sensors, a camera, and warning signs with flashing beacons upstream of the area where the ice develops to warn travelers. SRF prepared the plans, special provisions and estimate, and will be performing construction administration, and system integration. To address a stakeholder requirement, the system also sends an alert to district maintenance staff with a link to a closed-circuit TV camera for visual verification that can be viewed from a computer or smartphone. This allows district maintenance staff to determine the proper course of action to address the icy condition without having to travel to the affected area.
The system was installed in the fall of 2014 and an evaluation of system performance and effectiveness will be conducted during the winter of 2014 – 2015.