Iowa DOT News

What’s the “hole” story about the rough road conditions?

AMES, Iowa – Feb. 14, 2011 – Motorists are asking the Iowa Department of Transportation (DOT) “Why are some roads so bumpy? Why are there so many potholes this year?” 

The Iowa DOT says the answer has to do with a combination of factors, including an aging and deteriorating road system, an unusual amount of precipitation and cold temperatures. 

Have you ever placed a beverage can in the freezer to chill and forgotten to take it out?  If you were lucky, the can simply bulged and became disfigured. If you were not so lucky, it burst releasing its contents in the freezer. 

This is very similar to what is happening to our roadways. The moisture that has seeped through the cracks and joints of our aging roads has become trapped beneath. When the subsurface temperatures freeze, the moisture expands. Pressure from the significant quantity of expanding moisture is causing the pavement to bulge, heave and/or fracture. 

When the pavement is elevated, it is vulnerable to further damage from snowplow blades and heavy and frequent traffic. Bit by bit each fracture and crack spreads and, before you know it, you have a good-sized pothole. 

So what can be done about the problem? While some temporary pothole patching is being performed between winter storms, there is nothing that can be done about heaved sections until warmer temperatures arrive and pavement can naturally resettle in place. Once this occurs, road crews can make short-term repairs by sealing cracks and joints and patching the potholes and fractured areas with longer-lasting materials. In the long term, roads that are deteriorating must be replaced when funds become available or the situation will repeat itself the following winters and only worsen from year to year.  


For more information, contact: Bob Younie at 515-239-1589 or [email protected]















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