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Metropolitan Water Reclamation District of Greater Chicago

It’s that time of year when Chicago area residents brave the wintry air to salt sidewalks, walkways and streets. Winter is here and the Metropolitan Water Reclamation District of Greater Chicago (MWRD) is urging smart, efficient handling of road salt.

Road salt can provide safety and help the Chicago area thaw out of icy conditions, but it also has unwanted ramifications for the local water environment. Rock salt (sodium chloride) and salt runoff can be harmful to pets, wildlife, insects, bodies of water and soil along roadways and sidewalks. In addition, excessive road salt can impact vegetation and invasive species, as well as contaminate groundwater and drinking water.

According to the Salt Smart Collaborative, chloride levels in northeastern Illinois rivers, lakes and wetlands have been on the rise for decades. The challenge with protecting Lake Michigan and the Chicago Area Waterway System (CAWS) is that road salt use increases with urban development, and the more development, the more miles of roads and walkways that need winter deicing. All that salt eventually makes its way to area waterways, and MWRD water reclamation plants cannot always filter it out before releasing it as clean water into the CAWS.

“Like any form of pollution across the landscape, road salt can enter sewers or waterways through stormwater runoff and eventually degrade local water quality,” said MWRD President Kari K. Steele. “Once chlorides enter the water, it is difficult and expensive to remove them. We urge salt users to be cautious when salting sidewalks and streets this winter.”

MWRD Commissioner Cam Davis said to “Pretend your sidewalk is your dinner. Don’t over-salt. It’s bad for your lawn’s health. If you have a dog, it’s bad for their paws when Spot goes for a walk. And it’s bad for the health of our rivers and waterways. So ultimately, it’s bad for our health, too. Salt less or use alternatives.”

To meet new chloride limits, the MWRD created the Chicago Area Waterways Chloride Reduction Initiative Work Group in 2015. The group's goal is to allow stakeholders to develop and implement best management practices to address chloride issues. While the MWRD is not a major salt user, its mission to protect the area waterways and environment makes this topic a priority.

The MWRD has partnered with the Lower Des Plaines Watershed Group to provide the following “Salt Smart/Water Wellness” tips that help save resources while also protecting the waterways from potential contamination.

1. Shovel first. Salt should only be used after the snow is removed and only in areas needed for safety.

2. Size up. More salt does not mean more melting. A 12-ounce coffee mug of salt should be enough for a 20-foot driveway or 10 sidewalk squares (250 square feet).

3. Spread. Distribute salt evenly, not in clumps. Clumped salt is wasted salt!

4. Sweep. If salt is leftover on the ground after the ice melts, then too much salt was used. Sweep up leftover salt to keep it out of local rivers and streams.

5. Switch. Untreated salt stops working if the temperature is below 15 degrees. When temperatures drop that low, switch to sand for traction or choose a different deicer formulated for colder temperatures.

For more information, visit and download “A Healthy Waterway Begins with You: A Guide to Water Wellness” for more tips on how to protect the waterways year-round from contamination. 

Learn more about the Salt Smart Collaborative 

Video: Shoveling versus salting 


Press Release

Established in 1889, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) is an award-winning, special purpose government agency responsible for wastewater treatment and stormwater management in Cook County, Illinois.


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