WASHINGTON - Before every snow storm, trucks are out on the roads spraying lines of solution on the pavement.
So, what is that stuff?
That's an easy question for Charlie Gischlar of the Maryland State Highway Administration.
"It's a concentrated saltwater solution." he says. That means it is part water and part salt.
Gischlar says it's sprayed on the highway ahead of the storm "then when the precipitation first begins it prevents that initial bonding of snow and ice from occurring."
The District uses a similar solution with an additional ingredient of beet juice. Its solution is called a beet brine.
So is the stuff bad for your car? Gischlar says treat it like salt and within a reasonable time after the snow, hose down your car.
Now that the snow and ice have arrived, plows are no longer using the pre- treatment salt brine and are sticking with rock salt.
"We can't put that down on wet surfaces because it will just wash right off," Gischlar says.
When it comes to keeping roads de-iced during the storms, some in-road technology is at play.
"We also have embedded in most of the interstates around the area that we maintain, pavement sensors," he says.
The sensors detect subsurface temperatures, air temperatures, how much water is on the road and the salinity levels.
Then with the click of the mouse, transportation departments know what areas need more salt.
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