Short Answer: Pouring salt on roads and sidewalks helps prevent ice from forming, allowing pedestrians and drivers to use sidewalks and roads during the winter.

Ever wonder why some cities and towns spend money on trucks that distribute salt on the roads? Have you ever considered why it’s such a good idea to put salt on the sidewalk in front or around your house and the outdoor pathways leading to your house? Let’s dig into why this is the case.

According to this article from the National Aeronautics and Space Administration (NASA), the salt molecules bind to the water molecules from the water on the road, making it harder for the water molecules to bond with each other. This, in turn, reduces the chance of water freezing at its freezing point, or the temperature that a liquid turns into a solid, at 32°F or 0°C.

Salting the roads and sidewalks doesn’t completely eliminate the challenges of driving on cold roads. Even if the ice has melted, your car’s tires may still not get the best traction since the tires will still be driving on a surface that’s cold and wet. Cold, wet tires do not perform as well as warm tires driving on a warm road. Make no mistake: it’s much better than driving on ice and the salt might help your car gain some traction, but it’s still important to be careful when driving in the cold.

Unfortunately, many drivers still have to drive on frozen roads, even when salt is poured on them. This article from Scientific American explains how the air can be so cold to where the salted water on the road is still able to turn into ice. Furthermore, the article goes on to explain how it can potentially be harmful to the environment.

Bottom Line: Salting roads and sidewalks during a freeze may help improve mobility, but pedestrians and drivers should still use caution when walking on cold and wet sidewalks and roads with salt as ice may still form under very cold temperatures.

Image 4: A vehicle ready to tackle a cold wintry road

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