When Does Salt Not Work On Icy Iowa Roads?

The hot commodity of January is probably road salt.

So much salt, sand, and road de-icer has been poured in our area in the last few weeks, especially in the last 24 hours. I think half of it ended up in my car's undercarriage. If you drove around at all, you know the black ice is very real, it's slick, and even if a road has been treated, you have to be careful.

Temperatures have been in the negatives (for what seems like forever) and this morning, our cars were caked in ice. Today is warmer but is all of the salt still going to be effective?

When The Road Salt Won't Work

We know that at some point, it does get too cold for salt to be effective on slick surfaces. Melt Snow says that salt loses it's effectiveness in temperatures below 25 degrees Fahrenheit.

Sure when it's below 25 degrees like it is now, you can dump a bunch of salt on your driveway and say a bunch of prayers but it may still not be enough.

For example: at 30 degrees, 1 pound of salt will melt 46 pounds of ice. But at 15 degrees, that same amount of salt will melt 86% less ice.

This may be why I slipped on my apartment's freshly salted walkway this morning.

Luckily, the salt may actually work for us this week. Our pals at KWQC say that the highs this week will be in the 30's and we should probably keep the salt handy since there's sleet in the forecast.