Reducing Your Use of Rock Salt

After a winter storm hits, snow and ice need to be removed from facility walkways and parking lots. According to the U.S. Environmental Protection Agency (EPA), the most common substance used for deicing is sodium chloride (NaCl)—also known as rock salt. Rock salt is the same chemical as common table salt, only in larger granules, and it’s used for good reason, as it’s a very effective and inexpensive way to melt snow and ice.

But are you aware of rock salt’s darker side? While it might not cost much to buy and apply, the EPA reports that rock salt’s corrosive effects to cars, trucks, bridges, and roads result in approximately US$5 billion dollars in annual repairs in the United States.

In addition, road salt can infiltrate nearby surface and ground waters and contaminate drinking water. High sodium levels in drinking water can ultimately cause high blood pressure in human, and high chloride levels in surface waters are toxic to some fish, insects, and amphibians. Excess rock salt can kill roadside plants and harm wildlife that eat the salt crystals. The salty roads also attract animals like deer and moose who enjoy licking the salt, which increases the probability of accidents and roadkill.

Rock salt, being so effective and economical, might appear to be a necessary evil in removing snow and ice. However, there are some steps you can take to reduce your use of salt, thereby reducing some of its ill effects. The Arlington, Virginia, municipal website offers the following simple tips:

• Shovel early and often. The sooner you get to the snow, the less likely it will be to turn into ice.
• Divert downspouts to prevent ice. Direct your downspouts or sump pumps to drain onto lawn areas to keep your sidewalks and driveways free from ice. 
• Determine if salt is necessary. Ask yourself if salt on certain areas is even warranted. Will shoveling, sunlight, and sand be good enough? If you do use salt, don’t apply it until after shoveling of snow is completed.
• Consider alternative deicers. While sand doesn’t melt ice, it does increase traction. Another alternative is brine, which uses a quarter of the salt contained in traditional rock salt. According to this article by CNN, some communities are using other environmentally safe alternatives including beet wastewater (left over from sugar beet processing) pickle juice, and potato juice.
• Spread salt lightly and evenly. For every sidewalk square, use one tablespoon of salt. A 12-ounce mug of salt is enough for a 20-foot driveway.
• Watch the temperature. Salt won’t melt ice if the temperature is colder than 15 degrees Fahrenheit. In such a situation, consider using sand instead.
• Sweep and reuse. After the ice melts, be sure to sweep up the salt and put it into safe storage for reuse. Doing so gets the salt off the surface to prevent damage and protect wildlife, while preventing it from entering waterways.