Salt Smart Strategies to Reduce Aquifer Contamination During Winter
Did you know one teaspoon of road salt is enough to permanently pollute five gallons of water?!
Winter road salts are widely used on public and private properties to help melt ice and snow ensuring safe passage on roadways and walkways. Road salt works by lowering the freezing point of water so that it melts on roads and sidewalks despite surface temperatures being below freezing levels. These salts commonly known as, rock salt or deicer, contain high concentrations of sodium chloride that can contaminate waterways including groundwater systems like the Piedmont Sole Source Aquifer (SSA). This aquifer is a vital lifeline, providing drinking water to thousands of homes and businesses, supporting livestock, and sustaining crops grown by farmers who are integral to the Montgomery County and Maryland economy.
When road salt enters the environment, it becomes extremely difficult to remove from water supplies, and the consequences are far reaching as it does not breakdown. A Minnesota study revealed that 78% of salt applied for winter maintenance traveled to groundwater and local waterways, with 27% of monitoring wells exceeding EPA drinking water guidelines for chloride.
This issue isn’t unique to Minnesota—it is a concern here in central Maryland, where the Piedmont SSA plays a critical role in supporting rural communities, agriculture, biodiversity and natural ecosystems.
Here’s how high levels of chloride and and sodium affect our water, health and environment.
Public Health
Elevated chloride levels increases water salinity which can corrode pipes and plumbing structures. This can lead to costly infrastructure repairs and potential metal contamination in private wells.
High levels of sodium in drinking water can contribute to cardiovascular, kidney or liver disease. Elevated sodium levels are also linked to high blood pressure increasing the risk of heart disease and stroke.
Runoff and Soil Health
When salty snow melts it is either absorbed into the soil becoming part of groundwater, or runs down impervious surfaces into lakes, streams, and reservoirs.
Chloride-rich soils lose their ability to retain water and nutrients, exacerbating erosion and creating challenges for farmers trying to grow crops in already stressed soils.
Harm to Pets and Livestock
Pets and farm animals can ingest salt by licking their paws or drinking contaminated water which can make them ill.
Mammals and birds are attracted to salt on roadsides making them prone to vehicle collisions or can poison their bodies further disrupting ecological balance.
Freshwater fish may suffer from internal disfunction, delayed growth and disruption of aquatic ecosystems.
Be Salt Smart
Reducing salt usage is the most effective way to minimize contamination, protect vital groundwater resources, and our environment. Small changes can make a big difference.
Check the forecast: Avoid salting if a winter storm is predicted to begin with rain. Rain will wash away any applied salt. Sodium chloride salts are effective at temperatures 20 degrees and above.
Shovel First: Reduce the amount of deicer needed by clearing as much snow as possible before it freezes.
Use the Right Amount: More salt does not mean more safety! Just 12 ounces - the size of a mug of coffee - is enough to treat 10 sidewalk squares or 20 feet of driveway. Spread evenly and avoid clumping.
Protect Wellheads: Avoid applying salt near the wellhead, the visible part of your well located above ground.
Store Smart: Keep deicers in dry, covered areas to prevent runoff.
Sweep Up: After the thaw, sweep up any excess salt sitting on the pavement. It can be reused for the next storm.
By adopting smart salt practices you can contribute to safe drinking water, healthier soil, and a more sustainable environment for Maryland communities. Let’s work together to reduce salt usage and safeguard our water resources—because every teaspoon of salt saved makes a lasting impact.
