The Perils of Road Salt for River Life

Snow means salt on our sidewalks and streets, and that isn’t necessarily a good thing for the health of the Chicago River.

On WBEZ Radio, Margaret Frisbie, executive director of Friends of the Chicago River, and Karen Weigert, sustainability contributor to WBEZ’s Reset program, discuss the harmful effects of salt on the river system.

Listen to WBEZ Radio Interview 

Known as the “first flush,” pollution from stormwater runoff is most concentrated during the initial surface runoff of a rain/snow event. In winter months, it almost always includes road salt which is of great concern for river life because it is toxic to fish, plants, and other aquatic life, and once it is in the water it persists. One teaspoon of road salt can almost permanently contaminate five gallons of water.

In addition to waterways and groundwater, road salt affects native species the most. The hardest-hit species tend to be native ones not evolved to deal with the salinity. That reduces biodiversity down to the fewer native species that can tolerate road salt and gives invasive species an edge. Salt can also accumulate in soil near heavily treated roads or sidewalks, and draw moisture out of a plant’s roots, drying out the entire plant. 

Helpful tips for how to use and reduce the use of road salt:

  • Shovel first: salting before shoveling wastes salt.
  • Apply salt only where needed: around steps, the path to your car, and leading up to your household door.
  • More salt is not always better. A 12 oz. cup holds enough salt to spread across 500 square feet or about 80 feet of sidewalk.
  • When spreading salt, avoid clumps or piles; if salt is leftover after a snow event then you put too much down.
  • Salt takes longer to work the colder it gets. Switch to a salt blend formulated to work in colder temperatures below 15 degrees.
  • After a storm, sweep up the excess salt to use it again.
  • Tell your elected officials to use less too which saves tax payers money and helps the river too