Road salt, while helping to keep streets and sidewalks safe during winter weather, can have a big negative impact on streams and rivers and the freshwater creatures that inhabit them. New research from the University of Maryland posits stages of freshwater salinization, modeled after the stages of cancer. In the final stage, Stage IV, waterways suffer “system-level failures,” posing a threat to human health and aquatic life.
Sujay Kaushal, the UMD professor who led the study, says tracking the health of a body of water is similar to tracking the health of a human body. “If you don’t know where you are on the scale of your blood sugar or your cholesterol, you don’t know whether you have a problem or not,” Kaushal says. “When we have risk factors, guidelines and stages, we can effectively manage things.”
Unlike other pollutants, salt is not currently regulated at the federal or local level, though many jurisdictions have made efforts in recent years to cut back.