Getting Salty in Michigan: The Story Behind Winter Road Salt
LANSING, MI Winter and icy roads are synonymous in Michigan. More than 1 million tons of road salt is used annually on Michigan roads. A few "salty months" means safer roads and bridges for all Michigan residents.
Three common deicing chemicals used on roads are sodium chloride, magnesium chloride and calcium chloride. Each form can be used as a brine âˆ’ typically a salt-water solution that is sodium chloride and water. However, both magnesium chloride and calcium chloride are also used as liquids. When applied to roads, magnesium and calcium chlorides are more effective in lower temperatures than solid rock salt.
The three deicing chemicals can also be used as an anti-icing agent that is applied to roads before a storm to prevent ice buildup or as a pre-wetting agent, which speeds up the melting process and reduces bounce effect.
Road salt comes out of the soil three ways: Deep shaft mining, solution mining and solar evaporation. Once the salt is collected and crushed to the proper size, it makes its way to a county road agency.
The full story about road salt on Michigan's roads is featured in the Fall 2017 edition of Crossroads, the quarterly journal of the County Road Association (CRA) of Michigan.
Purchasing methods for road salt varies among road commissions and departments. Most county road agencies order their winter salt supply through the Michigan Department of Technology, Management, and Budget (DTMB) using the MiDeal statewide purchasing program. It can be a challenge to budget for road salt using MiDeal, as the price often isn't known until months after the bid is taken.
Others like the Kent County Road Commission (KCRC) orders road salt directly from a supplier.
"We control our own destiny when the bid is with us. We're not tied to MiDeal where if something goes wrong and we can't get the product there's nothing we can do about it," said Gerald Byrne, Deputy Managing Director of Operations at KCRC.
County road agencies use a combination of the many forms of deicing chemicals to limit ice buildup on the road, and work tirelessly keeping drivers safe during the snowiest of winter months.
The 83 members of the County Road Association of Michigan represent the unified voice for a safe and efficient county transportation infrastructure system in Michigan, including appropriate stewardship of the public's right-of-way in rural and urban Michigan. Collectively, Michigan's county road agencies manage 75 percent of all roads in the state, including 90,000 miles of roads and 5,700 bridges. County road agencies also maintain the state's highway system in 64 counties. Michigan has the nation's fourth-largest local road system.