Road Salt Pollution

The rock salt sold in hardware stores is usually the same substance that municipalities spread on roads during the winter months. Composed of 98.5 % sodium chloride, rock salt also contains small amounts of calcium sulfate, magnesium chloride, and rock. While the sodium dissolves quickly on driveways and roadways, the chloride stays behind. According to CNN, most of this chloride eventually finds its way into nearby waterways.

Aquatic contamination

Although chloride isn’t harmful at low concentrations, deposits can quickly rise over the course of a winter. The result is a toxic, salty soup harmful to the plankton and fish inhabiting our inland lakes and rivers.

One study into the increasing levels of road salt in waterways analyzed how the substance affected a common species of zooplankton, Daphnia pulex. Researchers found that increased exposure affected the species’ circadian clock, an important biological rhythm that could affect feeding and predation avoidance behaviors. “Since many fish prey on Daphnia,” Jennifer Marie Hurley, one of the study’s authors, wrote in The Conversation, “this effect could have ripples throughout entire ecosystems. Our work also raises questions about whether salt, or other environmental pollutants, could have similar impacts on the human circadian clock.”

Road salt in our groundwater

Too much salt is harmful to human health in other ways. The Transportation Research Board has noted that road salt can enter water supplies by percolating down through the ground or by running off from roads and parking lots into water reservoirs and shallow wells. Salt applied during storms often gets shoveled or ploughed into snow banks. When these melt, the salt gets washed into ditches or storm drains and ends up in the water supply.

In Canada, where between one and four million tonnes of salt is spread on roads annually (depending on the severity of the weather), the government lists common road salt as a toxic substance. Though some sodium is essential to a balanced diet, too much leads to health concerns. High blood pressure, increased cardiovascular disease, damage to the heart and kidneys, and harm to bones are just a few of the impacts that salt consumption can have if levels greatly surpass basic dietary recommendations.

Protecting our pets

Using road salt to melt the ice around your house may have other unintended consequences. Salt can be harmful to pets, who may lick it from their paws or fur after being outside. Even a small amount can be dangerous when ingested, causing vomiting, diarrhea, lethargy, disorientation, and even death (by sodium toxicosis) in high amounts. Salt can also irritate your pet’s paws, causing dryness, cracking and burns; when it enters cuts or blisters, salt causes further pain and irritation.

Vehicle and infrastructure damage

Salt is additionally hard on your vehicle, corroding the sub-frame and exhaust system along with your car’s muffler and hydraulic brakes. Bridges and reinforced concrete structures are also susceptible, since road salt increases rusting and speeds degradation. On pavement, salt increases shifting and cracking.

Harm to plants

When salt accumulates in soil, it reduces a plant’s ability to absorb nutrients. Salt spray generated from passing cars and trucks can also burn nearby plants. In some cases, the buds and twigs of some plant species lose cold hardiness and succumb to freezing temperatures more easily than those without exposure. Coniferous trees are particularly susceptible to damage from salt spray.

5 Alternatives to Using Road Salt Around Your Home

While many of the problems with too much salt in our environment come from municipalities and businesses applying road salt in large amounts, individual homeowners can make a difference. Fifty pounds of rock salt, or one average-sized bag, can pollute 10,000 gallons of water. That’s why storing your rock salt in a sheltered location away from wind and rain is important.

There are other ways you can lessen the impact of salt around your home, but the number one way is to use alternatives.

Shoveling

No one likes to remove snow by hand, but preventing it from accumulating on walkways and parking areas near your house will reduce the amount of ice that needs melting. If possible, shovel snow before it hardens. You can treat your shovel with oil, wax, or petroleum jelly before you start to prevent snow from sticking to its surface and to make the job easier.

Coffee grounds

If you aren’t saving your old coffee grounds for composting, consider sprinkling them on your walkway to melt ice. The acidity level in the grounds will help speed melting, and the grounds will provide some traction on slippery surfaces. This solution doesn’t work quickly, however, so it’s best applied when the temperatures aren’t too low and the sun is shining to help increase the melting effects of solar radiation.

Wood ash

Another solution that provides traction, wood ash speeds the melting of ice by darkening the snow and attracting heat from the sun. Additionally, wood ash contains potash, or potassium salts, which can help lower the temperature at which ice forms. If you already own a fireplace or wood stove, this option has the added benefit of being free.

Eco-Traction

This eco-friendly ice melter and road salt alternative is one of the easiest, safest, most environmentally friendly solutions on the market. Not only is it safe for kids and pets, Eco-Traction can make your lawn greener in the spring by improving soil aeration, along with water and nutrient retention. The product is made from volcanic minerals that provide better traction than sand and accelerate melting wherever they’re spread. Even better: you can re-use Eco-Traction by sweeping it up after the snow melts and storing for future applications. Other uses include lifting oil stains from concrete, preventing burns in a lawn from pet urine, deterring slugs, and amending lawn and garden soil.

Rubbing alcohol

Known for its sterilizing properties, rubbing alcohol has a lower freezing point than water (-20 degrees F) and is a quick fix when you want to melt ice fast over small areas. To make a quick and easy homemade ice melt, combine the following ingredients:

• 2 quarts (half a gallon) of water
• 2 ounces rubbing alcohol

Mix thoroughly and apply to ice. To increase safety, add some friction along with your DIY ice melter: this could include tossing some sand, gravel, or birdseed on the area. You can also combine rubbing alcohol and water in a spray bottle to keep in your car for de-icing locks and windshield wipers throughout the winter.

Responsible Road Salt Use

If you do apply salt around your home alone or in combination with one of the listed alternatives, consider the following recommendations:

• Treat only ice-covered areas rather than those covered in snow.
• Mix your rock salt with water before applying to create a brine. Spreading salt onto hard ice isn’t effective, since the salt won’t have a chance to work if it can’t permeate the ice. Making a brine will reduce the salt you need to use and will help ensure your salt works more effectively. (Note: never use hot water in your brine if you plan to use on car windshields.)
• Avoid applying salt or salt brine next to wells, ponds, streams, or plants.

And don’t forget: road salt works best at temperatures between 0 and -10 degrees Celsius (32 and 14 degrees Fahrenheit). When the mercury plunges beneath that mark, your best bet is to bring out alternatives—including your shovel.

Pin for later: