Save Money and Protect Soil and Streams with Thoughtful Deicer Use
With the potential for winter weather, North Liberty’s Stormwater Advisory Board encourages businesses and residents to think about how using less deicer can save money and protect soil and streams. Anti-icing products are another solution that requires lower use, making it more cost effective and better for the environment.
The salt applied to sidewalks, parking lots and streets contains a water pollutant called chlorides. Once these salts get into soil and water ecosystems they don’t go
away. When snow and ice melt they enter the storm sewer system that drains to local water bodies. Research studies conducted in Minnesota and Wisconsin indicate that elevated chloride levels are showing up in local lakes and streams and shallow groundwater.
High amounts of chlorides are toxic to fish and other aquatic life, and excess salt discharges onto soils near paved surfaces can cause soils to loose their ability to retain water and make them less permeable. Salts that percolate through the soil can contaminate groundwater which many cities and residents rely as a source of drinking water. Additionally, salts can be harmful to pets and wildlife such as birds, and cause corrosion of concrete, metal infrastructure such as
bridges and vehicles.
Salt is often over applied. The table below shows how much ice a pound of sodium chloride at a given pavement temperature and its melting time.
|Pavement Temp. (°F)||1 pound salt (NaCl) melts||Melting time|
|30°||46.3 pounds of ice||5 minutes|
|25°||14.4 pounds of ice||10 minutes|
|20°||8.6 pounds of ice||20 minutes|
|15°||6.3 pounds of ice||60 minutes|
|10°||4.9 pounds of ice||Salt is ineffective and will blow away before it melts anything.|
The Iowa Stormwater Education Partnership offers a simple resource with additional information, which you can download.