While creating a safe environment during icy weather is a top priority, it’s also important to choose an ice melt that won’t harm pets, plants, walkways, and waterways.

For example, some de-icing chemicals harden the soil and make it too salty for plant growth, others overload it with nutrients that can reduce oxygen levels in nearby streams and ponds. Still, other products corrode concrete, roadways, bridges, and cars.

And all ice melts get washed off into rivers and streams when it eventually starts raining instead of snowing, and percolate into our groundwater where they can impact water supplies.

Our suggestions:

• Avoid Sodium Chloride or “rock salt”. Traditional rock salt (sodium chloride) is pretty much of the worst of all available options.
• Look for “Pet Safe” and “CMA”. Products marketed as “Pet-Safe” will also be eco-friendly. Products containing a significant amount of calcium magnesium acetate or “CMA” are some of the most benign options commonly available.
• Apply in advance of a winter storm. Early attention before a storm will help prevent the formation of ice. When the snow starts falling, the ice melt will create a brine solution, helping to prevent ice from bonding to the surface.
• Disperse ice melt properly. Contrary to popular opinion, using large amounts of ice melt does not affect the speed in which ice and snowmelt. Using too much product can damage surfaces and harm the environment.
• Use a mechanical spreader for accurate coverage. The proper coverage rate is about one cup per square yard. This coverage will fan out and undercut the ice so that you can shovel the walkway clear.
• Continue to disperse ice melt during a storm. This helps to prevent snow from becoming hard-packed on surfaces.
• Don’t use salt as a substitute for shoveling. Sometimes a better shoveling job upfront will eliminate the need for ice melt altogether or let you get away with a bit of sand instead (though overuse of sand can also be a problem).

If a product claims to be “pet-friendly” it is likely to be eco-friendly.

Additional resources:

• Grist.org review of three eco-friendly ice melts.
  • While the author states that the best approach is to avoid ice melts, he claims that the most eco-friendly product contains: Magnesium chloride hexahydrate, calcium chloride (2-3%), potassium chloride (0.5-1%), sodium chloride (0.5-1%).
• From the MadSci Network: Using Salt to Melt Ice
• From Peter’s Chemical Company: How Ice Melt Products Work