CHAMPAIGN — Frustrated Illinois drivers are wondering why days after a heavy snow, some state roads are just now starting to clear.
The Illinois State Water Survey's Walt Kelly says the answer is simple: It's been too cold.
Kelly told The News-Gazette in Champaign that salt is effective down to about 20 degrees above zero. With temperatures far colder across much of the state on Monday and Tuesday there wasn't much point in trying to salt roads.
Champaign city spokesman Kris Koester says chemicals such as calcium chloride wouldn't have been effective this time, either, because they would have just melted the top layer of snow long enough to allow it to refreeze as ice.
So when might roads clear? As temperatures reach freezing and above later this week.