As public works professionals in the northern half of the nation prepare for winter, many are reporting skyrocketing prices for a snow and ice removal essential: road salt.

In Illinois, Ohio, and Michigan, local agencies are paying roughly one-third more than they paid last year.

The Chicago Tribune reports:

Even towns that are still buying salt through the state bidding program, or those that typically buy on their own, are seeing far higher prices this year.

Oak Park received a $74.21 per-ton bid through the state program compared with $50.67 last winter. The suburb's trustees will vote Oct. 6 on whether to accept the bid for 4,500 tons of salt.

"We weren't happy about (the nearly 50 percent increase), but that's the price that we have and at least we have salt that we'll be able to get," Oak Park Public Works Director John Wielebnicki said.

What's behind the higher prices?

As with any commodity, it comes down to basic supply and demand. Last winter was tough and salt use went way up. Mark Klein, a spokesman for Cargill, told The Tribune:

... suppliers are strained because of "huge usage" that left little in the pipeline.

Plus, he said, there is an increase in the amount of salt being sought for the upcoming winter after communities saw supplies depleted last snow season, when about 80 inches fell in the Chicago area from November to April. "It was an unprecedented winter," Klein said.

What are the alternatives?

Road salt washes off pavement, posing a hazard to local water supplies; and is considered a possible pollutant under the National Pollutant Discharge Elimination System. One way to stretch a limited supply is to combine it with other materials.

Sand is most commonly used, but it’s not the only option.

Public works agencies are working with local businesses to buy (or get for free) manufacturing byproduct the company has to get rid of anyway. They're experimenting with additives such as cheese brine and molasses, rum and vodka distillery leftovers, and sugar beet juice.

Another option is to reduce "bounce and scatter." Properly calibrated dispensing equipment can cut waste by nearly 35%.

Combined, new materials and spreading finesse can potentially reduce usage, and thereby lower costs.