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Using cheese brine to de-ice Wisconsin's wintry roads

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There are no cats in America, and the streets are paved with cheese! If only the Mousekewitzes had landed in Wisconsin, where road crews are using cheese brine to keep city streets from freezing. 

In December, Milwaukee began a pilot program to repurpose the saltwater leftovers from manufacturing cheese. Mixing the dairy waste with traditional rock salt and then spraying it on the road will hopefully trim costs while easing pollution. New York Times reports

The city gets 50 inches of snow each winter on average, and the costs of snow and ice management can exceeded $10 million a year. Last year, they used 44,000 tons of salt. 

But conventional road salt can spread too thin, polluting waterways when it washes away; about a third of dry salt is lost due to bounce and traffic. To limit its use, local governments across the nation have been experimenting with cheaper methods, like molasses from beet juice and spent brewery grain

Turns out, the cheesy mixture sticks well to roads and freezes at a lower temperature than regular salt brine. 

“You want to use provolone or mozzarella,” says Jeffrey Tews from the public works department. “Those have the best salt content. You have to do practically nothing to it.” 

In 2009, Polk County in northern Wisconsin started using cheese brine on highways, saving $40,000 in rock salt expenses that year. They spread more than 40,000 gallons last year. 

What could go wrong with cheese-coated streets? Officials are worried that the faint odor would attract rodents. The New York Times explains

If at first it sounded like a joke, the reality of tapping the wellspring of dairy byproduct has become a serious budget-slimming conversation. The state produced 2.7 billion pounds of cheese in 2012, the most of any in the nation. With it comes a surplus of brine that is shipped to local waste treatment plants. (Cheese brine is permitted on roads if limited to eight gallons per ton of rock salt used.) 

And it’s a good deal for lots people in America’s dairyland. By donating the excess liquid to municipalities willing to cart it away, one dairy company says it’s saving $20,000 a year in hauling costs. 

This pilot project will cost about $6,500, mostly for transportation and storage. 

Happy cows may come from California (I’m admittedly biased), but de-icing roads with a cheesy waste product? That’s amazing. 


Image: making fresh mozzarella by Kjunstorm via Flickr

— By on January 11, 2014, 12:32 AM PST

Janet Fang

Contributing Editor

Janet Fang has written for Nature, Discover and the Point Reyes Light. She is currently a lab technician at Lamont-Doherty Earth Observatory. She holds degrees from the University of California, Berkeley and Columbia University. She is based in New York. Follow her on Twitter. Disclosure