As the snow and ice arrive, so does the recurring battle to manage paved surfaces. Salt – used to de-ice our paved surfaces – is commonly over-applied. We scatter an estimated 445,000 tons of chloride-laden salt in Minnesota each year. More than 70 percent of that mixes with stormwater and ends up in our lakes, rivers, and streams, where it is toxic to fish and other aquatic life.
It takes only one teaspoon of salt in five gallons of water to exceed water quality standards for chloride and create conditions that harm aquatic life. There is no economically feasible way to remove chloride from water, so preventing chloride contamination is critical. Chloride from de-icing is one of the largest contributors to a growing salty water problem in Minnesota.
Ways to use less salt safely
• That crunch from sidewalk salt under your feet does not signify safety. People often think more salt equals more snow and ice melt. Salt is most effective when grains are scattered about 3 inches apart. Around 12 ounces – roughly a coffee mug full – effectively treats a 20-foot driveway or 10 sidewalk squares (about 1,000 square feet). Aim to apply salt consistently (e.g. with a spreader), and use only in critical areas.
• Sweep up visible salt on dry surfaces. It is no longer doing any work and will be washed away into local waters. You can keep it to use later.
• Shovel. The more snow and ice you remove, the less salt is needed to be effective.
• De-icing salt doesn’t melt ice when it’s below 15 degrees outside. Sand doesn’t melt ice but it does provide traction.
• Don’t expect perfect conditions: Slow down and drive carefully. Always give plow drivers plenty of space to do their work. Consider purchasing winter tires. Dress and walk appropriately for the weather conditions. Give yourself and winter maintenance professionals extra time.
• Look for signs of liquid salt application, which look like white strips on bare pavement. Many organizations are using liquid salt before a storm hits to prevent snow and ice buildup. This effective practice reduces salt use, provides great safety, and protects our environment!
• When you need someone to shovel or plow for you, hire a certified Smart Salting contractor trained to reduce salt use. Advocate reducing salt use in your community, at schools, churches, local businesses, and government.
For cities looking to reduce salt use and associated costs, the MPCA has a new model ordinance for municipal officials who are considering regulating the use of deicers to protect water quality, animals, human health, and infrastructure; or as part of their stormwater program. The agency also offers training for property managers on how to reduce their salt use. Learn more on the MPCA Smart Salting Training Certification page.
Visit the MPCA’s Chloride webpage to learn more about the benefits of reducing salt use.