Most salt used on roads ends up in our waterways

Physorg.com - Research: Most road salt is making it into lakes and rivers

A study conducted in the twin cities traced rising salinity in the rivers, streams and other fresh water bodies to a similar rise in use of road salt since 1984. The estimate was that nearly 70% of the salt applied to melt snow and ice is flowing and staying in watersheds. Even small amounts of salt in water can affect the ecosystem and threaten fish, amphibians and other aquatic animals. In addition, it is expensive and difficult to desalinate water. Researchers also offered some solutions: apply salt more intelligently, and refrain from salting when the pavement temperature is below 15F, since it is generally ineffective.