Urban snowmelt runoff carries diverse pollutants, like gas combustion products, snowmelting agents, and automotive exhaust, which threaten the quality of the receiving waters, like the North Platte River.
Pollutants can affect water quality faster two ways in winter. First, snow collects contaminants and releases them in concentrated form during melts. Second, the partially frozen state of rivers lessen the ability for self-purification.
Keeping walks and driveways clear, using snowmelt “sparingly and caringly”, and driving only when necessary are good winter water quality measures.
As much as 75 percent of water supplies in some western states are derived from snowmelt, according to the United States Geological Service (USGS). The Nebraska Panhandle relies heavily on snowmelt for our water supply – so taking care of our snow means taking care of our water.
This week’s snow may require some walkway de-icing before holiday gatherings tomorrow. There several options for ice melt, each with its own advantages.
1. Rock salt, or sodium chloride, is inexpensive and effective. It works well in temperatures over 20 degrees. However, it is toxic to plants, corrosive, and can burn pet paws.
2. Magnesium chloride less corrosive to concrete, less irritating to skin, and less toxic to plants. It is effective to 5 degrees Fahrenheit.
3. Calcium chloride works in temperatures down to -20 degrees Fahrenheit. Very little calcium chloride is needed to handle most icy conditions.
4. Potassium chloride and urea are considered safe to use around vegetation. Both require a higher rate of application than the other options and work down 12 to 15 degrees Fahrenheit.
4. Calcium magnesium acetate (CMA) is safe for the environment, biodegradable, and non-corrosive to concrete and metal. It works to 20 degrees Fahrenheit. CMA doesn’t need to be applied as much as rock salt to be effective, but does need to applied before the snow and ice accumulate to be most effective.