Runoff Rundown: Road Salt
By Chris Barnes/Assistant City Engineering
Released/Published: Jan 10, 2011
It’s cold and the snow is flying! While some of us would like to avoid the outdoors as much as possible during this time of year, unfortunately we’re forced to deal with snow and ice buildup on our driveways and streets. This means shoveling, snow-blowing or plowing and adding a de-icing agent like sodium chloride (“road salt”) for safer and easier travel.
Road salt works by lowering the freezing point of water, keeping ice and snow from bonding to pavement. This allows for easier removal by snowplows and shovels. But have you ever stopped to consider the effects salt has on the environment?
Melting snow and ice as well as winter rains cause salt to run off of drives, sidewalks and streets. The salt-laden runoff eventually makes its way into yards, ditches and storm sewers, and ultimately into plants, the ground and our creeks, lakes and other water bodies, thus contaminating the environment.
The large-scale use of road salt began in the 1950’s. About 15 million tons of de-icing salt are used in the United States each year. In 2009, the City of Canton used approximately 10,000 tons of salt to treat a total of 53,391 miles of city streets.
Being sensitive to the negative impacts of salt on our environment, the city has and will continue to use and explore other materials to reduce the amount of road salt applied to our streets. For example, the city utilizes road salt additives such as magnesium chloride and beet juice to reduce the amount of raw road salt usage by up to 30 percent.
An anti-icing agent such as brine (a mixture of rock salt and water) is sometimes applied to streets before precipitation forms on them and prevents ice from bonding to the pavement. Other practices are employed as well, such as keeping salt properly stored under roof when not being used and preventing over-application by ensuring proper settings on applicators.
Please join the city in our efforts to reduce environmental impacts from salt. Consider environmentally-friendly alternatives, use only minimal amounts necessary and keep unused salt properly stored and away from direct contact with storm water.