Winter presents significant challenges to roadway safety, especially during heavy snowfalls when visibility is low. While snowplows are essential for maintaining safe and clear roads, their presence on the road can create safety risks for both plow drivers and other vehicles. A recent Minnesota Department of Transportation (MnDOT) webinar highlighted the latest research developments in snowplow technology that aim to improve overall roadway safety, enhance snowplow operations, and reduce the risk of crashes.
Keeping snowplow drivers in their lane
One innovative technology discussed was the snowplow driver-assist system (SDAS)—the culmination of decades of work by U of M researchers and students in projects funded by MnDOT and other sponsors and partners. Cory Johnson, administrative engineer for MnDOT’s Intelligent Transportation Systems program and a technical liaison for the project, explained that the tool is designed to help snowplow drivers in low-visibility conditions stay in the correct lane and detect objects in their path.
With the goal of increasing driver safety, improving emergency response, and expanding operational hours during snow events, the SDAS features:
- An LCD dashboard screen and speaker behind the plow driver that shows where the plow is on the road and alerts the driver to lateral lane deviation and the presence of obstacles ahead—such as stalled or parked cars—so the driver can respond quickly.
- Precision GPS and radars that help plow drivers stay in their lane and detect the location of hazards—directly ahead, to the left, or to the right of the front of the plow.
The system has been tested in nine snowplows across Minnesota. While testing has shown promising results and overall driver satisfaction with the system, Johnson noted that more work is needed to improve reliability, obstacle detection, and scalability. MnDOT’s ongoing contract with the U of M will support further refinements through 2025.
Reducing rear-end collisions
Rear-end collisions with snowplows are another major winter challenge, according to Steven Blaufuss, statewide maintenance work-zone and operations specialist with MnDOT. These crashes likely occur because of the slower speeds of snowplows, higher speeds of approaching vehicles, and confusion caused by the current rear-light design on snowplows. Drivers following snowplows may struggle to accurately judge the plow’s speed, size, and light signals—particularly in low-visibility conditions—which can increase crash risk.
To address this issue, MnDOT and the U of M are working to develop new rear-light configurations and alert systems. The current system, which includes a mix of colors, flashing rates, and patterns, may create “visual noise,” according to the researchers. This—along with flashing variability and the lack of looming cues—may make it harder for drivers to interpret the plow’s signals, potentially delaying their reaction times.
Proposed lighting improvements aim to simplify the existing configuration and provide clearer visual cues to help approaching vehicles better assess the size, distance, and movements of snowplows. Key features of the proposed design include:
- High-contrast amber lights that create a solid, steady-burn outline of the plow
- A simplified light bar
- High-center brake lamps that make it easier for drivers to notice when a plow is braking
Tests of three lighting configurations in driving simulators have shown promising results. Of those, a new lighting configuration with an added audio-visual alarm showed an increase in time-to-collision and distance following braking as well as improved braking response time. These findings suggest that implementing the proposed lighting and alert system could reduce rear-end collisions with snowplows. Field testing of the new design on two snowplows is currently planned for late winter 2025.
The future of snowplow safety
Keeping roads safe during the winter season is no small task. The benefits of advancements like driver-assist systems and new lighting configurations underscore the importance of continuous innovation in roadway safety. Continuing to test and refine these systems may help shape the future of winter maintenance, contributing to safer roadways for all.
—Krysta Rzeszutek, CTS digital editor
