MILWAUKEE - In a state whose license plates advertise it as America's Dairyland, where lawmakers once honoured the bacterium in Monterey Jack as the state's official microbe and where otherwise sober citizens wear foam cheese-head hats, road crews are trying to thaw freezing Wisconsin streets with a material that smells a little like mozzarella.

This month, Milwaukee began a pilot program to repurpose cheese brine for use in keeping city roads from freezing, mixing the dairy waste with traditional rock salt as a way to trim costs and ease pollution.

"You want to use provolone or mozzarella," said Jeffrey A. Tews, the fleet operations manager for the public works department, which has thrice spread the cheesy substance in Bay View, a neighbourhood on Milwaukee's south side. "Those have the best salt content. You have to do practically nothing to it."

Local governments across the country have been experimenting with cheaper and environmentally friendly ways of thawing icy thoroughfares, trying everything from sugar beet juice to discarded brewery grain in an attempt to limit the use of road salt, which can spread too thin, wash away and pollute waterways.

Snow science experts say an attempt to recycle the salty brine that flavours cheese was only a matter of time, particularly in a state like Wisconsin.

"We're just trying to make every possible use of cheese," said Tony Zielinski, an alderman who represents the Bay View district, adding that local governments in other states have called him to learn more about the program. "If this takes off, if this proves to be a success here, I'm sure that it will be used in cities all over the country."

But in this dense urban setting, Milwaukee officials are reviewing a list of potential problems that come with cheese-coated streets: Would a faint odour of cheese bother residents? Would it attract rodents? Would the benefits of cheese brine, said to freeze at a lower temperature than regular salt brine, be enough to justify the additional hauling and storing requirements?

If at first it sounded like a joke, the reality of tapping the wellspring of dairy byproduct has become a serious budget-slimming conversation. Chuck Engdahl, the waste water manager at F&A Dairy Products in northwestern Wisconsin, said his company now donates most of the excess liquid to a handful of municipalities willing to cart it away, including Milwaukee, saving about $20,000 a year in hauling costs.