Being Salt Smart does not only apply to our diets.
We are also oversalting our sidewalks, parking lots, and roadways in an effort to reduce ice-related injuries. Unfortunately, our thoughtful effort is also causing chloride toxicity in our waterways and impacts aquatic life, soil and human health.
In the United States, the use of chloride-based salts for winter road deicing has increased steadily since its initial usage in the 1940s. Between 1975 and 2003, the use of salt for deicing more than doubled from 8 to 18.5 million metric tons (USGS, 2014), with current use in excess of 22 million metric tons annually (Bolen, 2022).
Through the National Great Rivers Winter Chloride Watch program, local citizen scientists have been collecting water samples along the Kishwaukee River Basin in DeKalb since December 2023.
Chloride concentrations (Cl-) have ranged from 65 ppm to as high as 441 ppm! The U.S. EPA has set the aquatic life criteria for Cl- at 230 ppm for chronic exposure and 860 ppm for acute exposure. Studies are ongoing, looking at the tolerance ranges for aquatic ecosystems and how salt deposits in roadside soil and vegetation impact the gradual release of Cl- concentrations in the warmer months.
Consider the impact to wildlife and domestic animals of excess salt on our roadways.
In our home, we don’t use salt at all for the sake of squirrels and dogs who walk regularly through our neighborhood. Since they don’t wear shoes as humans do, their soft little paws are subject to pain just by walking and doing their business on my street.
While it is important to make sure our city workers are using “Salt Smart” practices, a study has also shown that “non municipal (residential and commercial) applications are likely contributing heavily to Cl- concentrations due to application rates on parking lots and walkways that may be several times those used on roadways (Perera et al., 2010).”
So, let’s collectively protect our groundwater and drinking water by following the recommendations below:
- Shovel first. If you feel that you must use salt, use it AFTER snow is removed and only apply it in areas needed for safety.
- Use the correct amount. A 12-ounce coffee mug of salt should be enough for a 20-foot driveway or 10 sidewalk squares (250 square feet).
- Distribute salt evenly, not in clumps.
- Sweep up and reuse excess salt to keep it out of the local rivers and streams!
- Switch to appropriate de-icer. Untreated salt stops working if the temperature is below 15 degrees. For treatment below those temps, switch to sand for traction or choose a different deicer formulated for colder temperatures.
Other alternatives for de-icing include beet juice, coffee grounds, vinegar, and salt in liquid saline form. Commercially, you can also obtain Safe Paw Ice melt from stores like Lowe’s and Home Depot.
For more information about Being Salt Smart, visit: www.saltsmart.org
- Julie Jesmer is the chair of the DeKalb Citizens' Environmental Commission.