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Missouri Thanksgiving Travel: Why I-70 Road Salt May Not Be Enough
Columbia, MO – Missouri drivers preparing for Thanksgiving travel along Interstate 70 may be counting on road salt to keep the highway safe if winter weather develops. But even freshly treated pavemen
By Miles Carter · 2026-11-11T19:20:46.113Z
Columbia, MO – Missouri drivers preparing for Thanksgiving travel along Interstate 70 may be counting on road salt to keep the highway safe if winter weather develops. But even freshly treated pavement can become dangerously icy when temperatures plunge, creating a serious risk for motorists traveling between Kansas City, Columbia and St. Louis.
According to winter maintenance guidance from transportation agencies, traditional road salt becomes less effective as pavement temperatures approach 20 degrees Fahrenheit. Its ice melting ability declines further in the teens and single digits, making prolonged cold particularly challenging for highway crews.
Why Even Salted Missouri Highways Can Freeze Road salt lowers water's freezing point, helping melt snow and ice. However, it does not guarantee clear pavement or reliable traction.
Around 20 degrees, conventional salt melts ice more slowly than it does near freezing. Below approximately 15 degrees, salt alone may struggle to improve icy conditions quickly enough.
That matters along I 70 through Kansas City in Jackson County, Columbia in Boone County and St. Louis in St. Louis city.
Other major routes, including I 44, I 49, I 55 and I 35, can also develop slippery conditions despite treatment.
Bridges, overpasses and elevated ramps are especially vulnerable because they can cool faster than surrounding pavement.
Thanksgiving Travel Could Increase the Danger Thanksgiving falls Thursday, Nov. 26, bringing holiday travelers onto Missouri's interstate network connecting Kansas City, Columbia, St. Louis, Springfield and neighboring states.
If snow, freezing rain or sharply falling temperatures develop during the holiday travel period, even treated highways could become hazardous.
Missouri drivers should also watch for overnight refreezing, when wet pavement turns icy as temperatures drop.
The Missouri Department of Transportation uses plowing, salt and other winter maintenance treatments, but no method guarantees ice free roads in every condition.
Before departing, motorists should check National Weather Service forecasts and MoDOT's Traveler Information Map for updated road conditions, traffic cameras and travel alerts.
The bottom line: Salted does not mean safe. Reduce speed, increase following distances and remain alert for black ice, particularly on bridges and during overnight travel.