A recent episode of the “Talking Michigan Transportation” podcast reviewed a new study that confirms flashing light emitting diode or LED lights, when used strategically, can improve safety on roadway curves.
[Above photo by Michigan DOT]
That study – part of a larger research project funded by the Michigan Department of Transportation looking for effective speed warning technologies – concluded that “horizontal curves” on flat roads present a major challenge to drivers, especially when there is a significant difference between the posted speed limit and the curve advisory speed.
It also determined that Michigan suffered 128,517 crashes on curved roadways during winter weather conditions between 2018 and 2022, causing 175 serious injuries and fatalities, plus 1,360 less serious and suspected injuries.
Timothy Gates, a professor of civil and environmental engineering at Michigan State University and the study’s research leader, noted on the podcast that “flashing lights are a driver alert mechanism that still remains effective” yet are even more effective if they’re activated in an “on-demand situation,” such as when drivers approach a curve too fast in wet roadway conditions.
“So when we have this the combination of the flashing light and it have it activated in an on-demand sense – as in only when it needed, so it is not flashing all the time 24-7 – that’s really still perceived as one of best driver alert mechanisms that we have out there,” Gates explained.
He said the university conducted a related winter evaluation three years ago with on-demand flashing LED lights warning drivers to slow down when approaching icy bridge decks – and found that those signs were very effective.
“They were effective at reducing speeds approaching bridge decks,” Gates said. “That then prompted this project, which we just wrapped up, on M32 west of Gaylord where we installed slippery curve warning signs. The flashing LED is activated by a pavement sensor that detects when the friction at the surface of the pavement is below a certain value.”
He added that the study also concluded that such on-demand flashing systems will prove even more beneficial as “winter weather warning” systems at roadway curves where snow and ice is a regular occurrence.
“These are low-cost traffic control solutions that help guide motorists in these situations; improving safety for them,” Gates said.
To listen to the full podcast, click here.
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