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Vermont Winter Thanksgiving Travel: Salted I-91 Can Still Ice Over
Burlington, VT – Vermont drivers preparing to travel Interstate 89 and Interstate 91 this Thanksgiving may be trusting something that cannot always protect them: road salt. Even freshly treated highwa
By Tessa Morgan · 2026-11-11T19:00:50.182Z
Burlington, VT – Vermont drivers preparing to travel Interstate 89 and Interstate 91 this Thanksgiving may be trusting something that cannot always protect them: road salt. Even freshly treated highways can become dangerously icy when temperatures plunge, creating a winter driving hazard that motorists should understand before heading out.
According to winter maintenance guidance from transportation agencies, traditional road salt becomes significantly less effective as pavement temperatures approach 20 degrees Fahrenheit, with its ice melting ability declining further as temperatures fall into the teens and single digits.
And that's where a familiar winter safety measure can create a false sense of security.
Why Even Salted Vermont Highways Can Freeze Road salt isn't magic. It lowers water's freezing point, helping melt ice and reduce freezing under suitable conditions.
However, as pavement temperatures fall, the melting process slows considerably. Around 20 degrees, conventional salt works much more slowly than it does near freezing. Below 15 degrees, salt alone may struggle to produce meaningful melting quickly enough to improve traction.
For drivers traveling through Burlington in Chittenden County, Montpelier in Washington County, St. Albans in Franklin County and White River Junction in Windsor County, that limitation matters.
Major routes including I 89, I 91 and U.S. Route 7 can remain slippery despite treatment, especially on bridges, overpasses, shaded mountain roads and exposed stretches where windblown snow can accumulate.
Thanksgiving Travel Adds Another Concern Thanksgiving falls Thursday, Nov. 26, bringing holiday travelers onto Vermont's major highways and mountain routes.
If snow, freezing rain or falling temperatures develop during the holiday travel period, even treated pavement could become dangerously slick.
The threat can increase after sunset, when pavement temperatures drop and melted moisture refreezes.
The Vermont Agency of Transportation uses various winter maintenance methods, but no treatment guarantees completely ice free roads during extreme cold.
Before traveling, motorists should check National Weather Service forecasts and Vermont 511 for current road conditions.
The bottom line: A salted highway is not necessarily a safe highway. Drivers should slow down, increase following distances and watch for icy patches even when roads appear clear.