Frigidly cold temperatures mean slicker roads around Wisconsin, because road salt is not as effective at melting ice at sub zero temperatures. "Salt really isn't working that well, so we're trying to as much scraping as we can and add some supplemental chemicals . . . to help that salt work a little better," explains Wisconsin DOT winter maintenance engineer Michael Sproul. Sproul says salt works great at temperatures in the teens and above, but on bitterly days like this, not so much.
"In the higher temperature ranges just below freezing, salt works wonderfully," explains Sproul. "It takes very little salt to melt a lot of snow or ice. Salt, in a lab, is effective down to about minus 6 degrees. In reality, we only use it down to about 15 degrees pavement temperature."
Sproul says drivers need to be aware that conditions are going to less than ideal on these super cold days, and to drive accordingly. "This isn't the first time you've driven in the snow this year, we should all be accustomed to it by now. And when these temperatures are really, really low, just throwing a bunch of salt on it isn't going to do anything to benefit the pavement."
One more reminder from Sproul: when it's slippery on the roads, the last thing you want to do is activate your cruise control. "If you're cruising along on your cruise control on dry pavement and you hit a slippery, you're cruise control will kick in to try and maintain that speed, and you'll go into a big spin."