Road crews dissolve icy snow on roadways with a spray of brine. Some communities pre-treat roads with the brine knowing that the salt on the road surface will melt any snow that falls. Using the same idea, homeowners can make their own brine to spray their driveway and walkways. Of course, brine needs to be safe for plants or when spring comes, all the plants around the edge of the sprayed areas will be dead.
Fill a bucket with about 2 cups of wood ashes. Pour in a gallon of water and stir well. Allow the mixture to sit overnight.
Strain off the floating bits of charcoal and wood matter with a sieve, taking care not to disturb the liquid.
Pour the liquid into another clean bucket, stopping before any of the sediment at the bottom drains into the bucket. The fluid contains the dissolved potassium and sodium salts.
Add an equal amount of plain white vinegar to the bucket and mix. This acid will react with the potassium and sodium forming a weak potassium acetate and sodium acetate. Airlines use potassium acetate to de-ice their runways and planes.
Pour the liquid into your garden sprayer and spray over your driveway and walkways before the snow starts. The lowered melting point of the spray solution should keep ice from solidifying or snow from accumulating.