On snowy road surfaces, road salt does the trick to provide better traction. “Road salt is mostly sodium chloride, just like the table salt you put on your food,” said Sujay Kaushal, a professor of geology at University of Maryland. “Ions in the salt — little particles — squeeze themselves in between the water when it’s freezing, so that the water has trouble forming a crystal of ice.” However, Kaushal and fellow researchers from Maryland’s College of Computer, Mathematical, and Natural Sciences say the influx of salt in freshwater streams and rivers poses an “existential threat” to drinking water if current trends continue.
