Road Salt is a threat to our waterways.
Chloride, the key element in road salts, poses a threat to the health of our rivers and environment. When water runs over the landscape, it picks up pollutants along the way, including excess road salt and other deicing chemicals. These contaminants pollute our rivers, streams and lakes.
If used correctly, road salt can be a helpful safety precaution. When we use too much, we damage our roads and environment, while not increasing safety.
Elevated levels of chloride can disrupt an organism’s ability to maintain a natural internal water balance, which leads to impaired survival, growth and reproduction. High levels of chloride can be acutely (instantly) toxic to fish and lower levels of chloride over a longer period of time, or chronic exposure, can be just as toxic.
Milwaukee Riverkeeper’s Monitoring Efforts
In 2010, Milwaukee Riverkeeper began to work with the U.S. Geological Society (USGS) to monitor specific conductivity and chloride levels in our local rivers and streams. This work continues, Milwaukee Riverkeeper’s road salt monitors play a key role in identifying waterways reaching toxic chloride levels during the winter months in areas of the Milwaukee River Basin lacking data. Road Salt Monitors mobilize after heavy snow events, collecting data critical to understanding the frequency of chloride exceedances within the Milwaukee River Basin.
For more information about Milwaukee Riverkeeper’s Road Salt Monitoring Program and the impacts of road salt in our waterways please look at this story map.
Of the Milwaukee River Basin’s 500 miles of perennial streams, 117 miles are listed as impaired for chloride pollution on the Wisconsin Department of Natural Resources 303d Listed Impairments (2022).
Chronic exceedance is shown as a chloride concentration between >395 and <757 milligrams of chloride per liter, an acute exceedance is any chloride concentration >757 milligrams of chloride per liter. Data Sources: Milwaukee Riverkeeper & MMSD.
Interactive Map of Chloride Concentration in the Milwaukee River Basin (2002-2019)
This map allows you to look at the data collected by Milwaukee Riverkeeper volunteers and the Milwaukee Metropolitan Sewage District. Click and drag to look around the basin, or click on individual points to see details.
So, what can we do?
Shovel Early and Often. This reduces the need for salt.
Sweep up excess salt to reuse for future storms.
Use only the salt you need. 12 oz of salt is all that’s necessary for a 20-foot driveway or 10 sidewalk squares. Dedicate an old 12 oz coffee mug to measure the amount of salt you will need.
Spread the word! Talk to you friends and neighbors, share the toxic consequences and excessive cost of over salting. Download our Road Salt Graphics, and Handouts.
Write your local representative supporting responsible road salt practices for roads, sidewalks and public parking lots (draft letter here ). Encourage them to send winter maintenance applicators to attend our FREE workshops. List of certified municipalities are listed below.
Our three rivers need a low salt diet – join us!
Milwaukee Riverkeeper is working to determine if chloride concentrations from road salt are reaching harmful levels. Road salt monitors are needed to help collect data for this research. Sampling typically takes place within 48 hours after events that trigger road salt use such as large snowfalls and snowmelts.
We host an annual workshop on snow and ice control best practices for private contractors in an effort to reduce impacts of road salt to local water quality! You’ll learn state of the art winter maintenance practices, including how to transition to liquid deicers, to reduce overall salt application to parking lots, driveways and sidewalks.
Support Smart Salting Businesses
Support businesses who are implementing best practices to reduce the environmental impacts of road salts. Certified individuals have attended training, passed certification tests and agreed to use best practices when controlling snow and ice.
Thanks to our funders for their generous support of this program!