LOUISVILLE, Ky. — We don't need to tell you it's pothole season. In fact, you're telling us it's pothole season.

You're not imagining it if the 2019 winter season seems particularly bad for potholes. The Kentucky Transportation Cabinet says its patching material numbers are costs are up this year from the same time period last year.

KYTC pothole numbers graphic
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It's not a big mystery why potholes have been popping up all over the place these last few weeks. All we have to do is look to the insane rollercoaster that is our weather lately to understand why. You know how we've been going from sun to rain to snow over and over and over again? Well, it's literally the perfect storm for potholes. We've had 19 recorded days in the metro so far with maximum temperatures above freezing, minimum temperatures below freezing, and then some form of precipitation.

Weather transition graph
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Water is a unique element. It becomes less dense (i.e. expands) when it freezes. Potholes form in roads for the same reason that ice cubes float in your drink. Water fits into tiny spaces in the road as a liquid, and then expands and cracks it apart when it turns to ice.

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It's a simple scientific phenomenon, and it comes with a hefty price tag. AAA says around 30 million drivers have to fix their vehicles from pothole damage each year, setting them back between $250-1000 each.

A reminder: if you come across potholes on your travels throughout the metro, you should report them to either Metro Public Works or the Kentucky Transportation Cabinet. 

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