Keeping walkways safe in the winter can be challenging. Many homes and businesses use deicing chemicals that may impact local ecosystems and overwhelm drinking water systems. Deicing is not the only option and implementing best practices can help reduce potential pollution problems.
As melting snow and ice travel to storm drains, they pick up deicers and any other chemicals encountered en route. These chemicals can permeate into groundwater as they are washed along. You may believe your contribution is minimal or just “salt”, but think about the combined impact of each house on your block as chemicals concentrate in nearby waterways.
Some deicers are better than others and it is always wise to pick the right one for your area. Justin Mansberger, Extension Educator, Water and Master Watershed Steward Coordinator at Penn State University offers this advice:
Rock salt (sodium chloride) is the most used but contains cyanide as an anti-caking agent that can be toxic to underwater life and is the most harmful for plants due to its high chloride levels.
Calcium chloride is considered a better choice than rock salt because it does not contain cyanide. However, it can also harm plants because of chloride. Calcium chloride costs about three times more than rock salt, but you only need to use approximately one-third as much.
Magnesium chloride is considered the least toxic deicing salt because it contains less chloride than either rock salt or calcium chloride, making it safer for plants and animals. Still, it has levels of chloride that can cause issues.
Calcium magnesium acetate (CMA) is considered the best choice for safely melting ice. It is less toxic than deicers containing chloride but can cost considerably more than rock salt.
Other alternatives to deicers (for small areas) include warm water mixed with table salt or water, sand, or kitty litter. Never use fertilizer as a deicer.
Best management practices for deicing chemicals
As with all chemicals, follow label directions and use deicers and alternative options in the least quantities as possible. Be sure to store your deicers in the appropriate containers to prevent leaks or spills. Other ways to minimize deicing chemical impacts include
- Spreading deicer before snow and ice accumulate
- Removing as much snow and ice as possible before application
- Applying deicer only to areas where people or vehicles will be traveling
- Ensuring grains of salt are roughly 3 inches apart from each other
- Sweeping up extra salt to reuse
Remember, groundwater is our drinking water. Let’s work together this winter to keep Marion County’s drinking water safe!