Shaken, Not Poured: The Case for Using Winter Salt Sparingly

Little mounds of salt piled along buildings and sidewalks are a common sight during the winter months in the Great Lakes states.  Now that winter is fully upon us, the plow and salt trucks will be out in full force.  But why do we use salt?  And what is all of that salt doing to the environment?

Salt lowers the freezing point of water.  So, less water can become ice because there is salt in the water. 

What all of this means is that salt can decrease the number of traffic accidents due to slippery road surfaces.  It can also keep sidewalks and driveways clear for pedestrian traffic.  While it’s great that we have an abundant resource that allows us to get around in the winter, it also has some detrimental impacts on the environment and us.  Some impacts of sodium chloride use are:

1.       Damage to vegetation: When salty slush from roads, sidewalks, and driveways gets on your garden or lawn, the salt water can seep into the soil.  Plants can’t get water from the soil as easily, dehydrating them.  The salty water that ends up on leaves, it can desiccate the plant further.

2.       Corrosive to vehicles: Salt is hygroscopic, meaning that it attracts water.  If that slushy spray from passing cars gets on your car, the salt from that slush will attract more moisture to it and will lead to rusting. 

3.       Water pollution: As spring approaches and warmth returns to Wisconsin, the snow begins to melt.  You’ve seen it; rivers of melted snow, pouring into the storm drain.  It takes with it the salt that has been used throughout the winter.  Many storm drains, including the majority of Superior’s, take stormwater and snowmelt (along with anything mixed in to them) into streams, rivers, and lakes.  Lakes are getting saltier because the salt settles at the bottom of the lake and accumulates.  This prevents water from mixing and can be toxic to aquatic life.

What can you do to mitigate some of the detrimental impacts of salt while staying safe in the winter?  First of all (and most importantly), remove as much snow and ice as possible first.  Once it has been walked/driven on and is compacted, it will be more difficult to get rid of.  Second, pay attention to the products you’re using.  Different kinds of salts (besides the most commonly used NaCl) have different temperatures at which they are effective.  Sodium chloride works best at or above 20*F.  For colder situations, use a different product or use sand for traction.  Finally, apply using the guidelines set forth on the package.  Use a shaker to spread more evenly and to avoid spreading on your lawn or garden.  Sweep up excess salt and use it again for the next storm.

Some more links to check out:

City of Superior

Lake Superior Streams

Wisconsin Department of Transportation- Winter Maintenance at a Glance

-Written by Jillian Schubert Edwards