ROCKFORD (WREX) – During the winter season, the Illinois Department of Transportation plays a crucial role in keeping our roads safe.
It’s that time of year where the temperatures drop, the snow begins to fall, and driving can become more difficult. You have probably seen snow plows out after a fresh snow, or even got stuck behind one, but IDOT does more than just plow snow. Step one is pretreating.
693G0289_01 David Almy Operations Maintenance Field Engineer, District 20:44-1:00
We spoke to David Almy, the Operations Maintenance Field Engineer of District 2. He mentioned they used a brine mixture, referred to as liquid salt. IDOT has different trucks or tailers with a spray tank on it that go out to apply to roads and bridges mainly.
Before hitting the roads, there are a few things they look at to help make the decision of whether or not they should go pretreat.
Almy tells us that the agency keeps a close eye on the pavement temperatures, the forecast, and how close we are from the last storm in case there is any residual treatment still on the roads. Looking at the forecast being making any decision to go out is key.
IDOT doesn’t have meteorologists of their own to gather this information, they work with a company called DTN whose meteorologist provides them with the forecast.
They take the weather forecasts and use the weather models and then provide a forecast of what the pavement temperature is going to be and the conditions of that pavement based on the weather information, according to Ben Hershey from DTN.
You can imagine how crucial pavement temperatures may be to IDOT and keeping commuters safe.
Zoom Interview Ben Hershey
Hershey says DTN tries to make sure that we provide IDOT, with all the other weather information that’s out there, that tactical decision information to be able to make both what they consider real time decisions as well as the decisions that need to be made less than 24 hours out.
Making the right decision can be tricky during a weather situation as many times there are a lot of moving parts. Forecasting for these storms can be just as challenging but that’s why DTN works hard to prepare an accurate forecast and consistently communicate with IDOT.
We are all dependent on those decisions as it keeps our roads clean and ultimately keeps us safe while traveling. Snowstorms may be one of the most obvious hazards we see, but there is one hazard we dealt with just last year that brought many a big headache!
“Ice storms, ice storms are the hardest because the temperature differential over an area, you know one spot might be 33° and it’s not freezing, the next thing you know you hit a spot where it got a little bit colder and its freezing plus with the continuation of the rain um before it freezes it dilutes as soon as you put the treatment down, it starts diluting it. Lowering the effectiveness, so… Those are the hardest to keep track of”
February 22nd, 2023, a system that brought freezing rain led to the area being covered in just over a third of an inch in ice. With ice storms being one of the most challenging weather events, oftentimes it is when we see small amounts of snow that cause havoc on the roads.
“When there’s not as much snow out, people aren’t taken it as seriously it’s almost like a good 6-inch snow everybody knows it’s bad so they go slow, when you’ve got that one to two inches it can be enough to make it slick, but most people really don’t realize that it’s that much of an issue I think that’s cause they haven’t adjusted their driving to it.”
80% of reported crashes during the winter happen in 1-2 inches of snow, according to a study done by the National Weather Service in Wisconsin. Contrary to popular belief, it’s not the big snowstorms that cause a majority of car accidents.
It doesn’t take much to see slippery and hazardous conditions to develop on the roads. Almy suggests being patience when driving on winter roads and being aware of the pavement conditions, always give trucks plenty of room, and keeping your distance in general when on the roads.