Road Salt has Increased Chloride Levels in the Potomac by 85%

Salt used to keep winter roads free of snow is accumulating in waterways, leading to “damaged infrastructure, polluted drinking water, and harms to aquatic life,” writes Renee Bourassa in Greater Greater Washington.

The Potomac River, the sole source of drinking water for Washington, D.C, has seen a 10-fold increase in chloride over the past 80 years. “WSSC Water has seen chloride levels increase by 155% in the Patuxent River and 84% in the Potomac River over the past 30 years. Earlier this year, they even preemptively let their customers know to expect saltier water coming out of the tap after a storm.”

Bourassa explains that salt is corrosive to cars, household appliances, buildings, bridges, and plumbing, leading to quicker degradation of infrastructure and homes. Salt can also lead to the release of additional harmful chemicals into drinking water. It is also harmful to freshwater species. 

Some states, like Maryland and Virginia, are working to reduce winter salt application through targeted salt management plans. Bourassa also lists several ways residents can help reduce salt use.