Most de-icing products contain high levels of salt, which can damage driveways and sidewalks, be harmful to pets, damage lawns and other plants, and harm our waterways.
The Maryland Department of the Environment explains why salt can be detrimental to the environment:
Salt and the Environment (pdf document)
Soil: Excess salt can saturate and destroy a soil’s natural structure and result in more erosion and sediment transport to the Chesapeake Bay.
Vegetation: High concentrations of salt can damage and kill vegetation. Healthy vegetation is a vital buffer between land and water, reducing nutrient exports to the Bay.
Wildlife: Salt poses the greatest danger to fresh water ecosystems and fish. Studies in New York have shown that as salt concentrations increase in a stream, bio-diversity decreases.
Humans:Excess salt can seep into groundwater and runoff into reservoirs affecting the taste of drinking water. Additionally, sodium chloride can exacerbate hypertension.
Corrosion: Salt is corrosive and can damage exposed rebar, bridges, and automobiles. Additionally, by increasing the freeze/thaw cycle, salt can prematurely age cement and asphalt.
There are many alternatives to salt including potassium chloride, calcium chloride and magnesium chloride, corn processing by products, and calcium magnesium acetate (CMA). Most can be found in your local hardware store under various trade names – check labels for chemical content.
Despite the harm that they can cause to the environment, homeowners need to consider the importance of preventing falls around their homes during the winter months. Here are some tips from the Maryland Cooperative Extension and the Maryland Department of the Environment.
- Ice melting products are most effective when spread thinly and evenly over the pavement prior to ice formation. It is much easier to prevent ice than to try to melt a thick layer of ice. Avoid use of salt by clearing walkways of snow before it turns to ice and consider that salt and deicers are not effective when more than 3 inches have accumulated.
- Follow the manufacturer's directions when applying a deicer. If possible, use even less than is recommended, but make sure the surface is covered thinly and evenly.
- To melt thick ice in very cold weather, add a small amount of water to the deicer to help initiate melting. To further aid melting and provide sure footing, mix the deicer with wet sand and/or ashes.
- For areas with a thin layer of ice, instead of deicer, try applying warm water mixed with table salt, water conditioner salt or the brine backwash from a water conditioner.
- Use sand, ashes or kitty litter to improve traction on icy areas.
- Once a dry route to the house has been established, block off slippery areas to prevent personal injury.
- If an ice storm is predicted, cover small areas with heavy plastic or other water proof material.
- Consider the temperature. Salt and CMA have a much slower effect on melting snow and ice at temperatures below 25 degrees Fahrenheit.
- Track winter weather and only use salt and deicers when a storm is imminent. If a winter storm does not occur, sweep up any unused material, store, and reuse for the next big storm.
- Apply deicing products discriminately, focusing on high-use areas where traction is critical and apply the least amount necessary to get the job done. This will save money in product costs and will also help minimize property damage to paved surfaces, vehicles, and vegetation.
- Plant native vegetation that is salt tolerant in stormwater drainage swales and ponds that may receive salt-laden runoff. Not only will these native species have a greater chance for survival, but they will continue to act as an effective buffer for the Chesapeake Bay. (Recommended trees and bushes: high bush blueberry, bayberry, green ash, black locust, sycamore, sweet gum, pin oak, hemlock and bald cypress)
- Store salt and other products on an impervious surface to prevent ground contamination and in a dry, covered area to prevent stormwater runoff.
Melting Ice Safely, Maryland Cooperative Extension (pdf document)
Winter Weather, Chemical Deicers and the Chesapeake Bay (pdf document)