Starting in December 2021, the Allegan Conservation District recruited volunteers to monitor road salt concentrations along the Kalamazoo and Rabbit Rivers. Volunteers have been collecting monthly water samples to help ACD build a baseline database to monitor changes in road salt concentrations at 14 sample sites. Monthly samples and monitoring will continue through November 2022.
For more information on this project, or to sign up as a volunteer, please visit our Winter Salt Watch Program Page, or call our office at (269) 941-6165.
In addition to road salt concentrations, volunteers are asked to monitor for invasive species and evidence of erosion at their assigned sample locations. This information has the potential to help the Allegan Conservation District identify areas for invasive species management and streambank stabilization. So far, volunteers have reported the presence of invasive phragmites and tatarian honeysuckle.
Of the data collected so far, there have been no remarkable findings. Chloride concentrations have fluctuated from month to month between all 14 sample sites. According to the Izaak Walton League of America, chloride begins affecting freshwater aquatic life at 100 ppm (mg/L). Fortunately, volunteers have not yet recorded road salt concentrations of that level at any of the 14 Allegan County sample sites. However, we are not out of the woods yet. Road salt applied in the winter can remain present in our soils and waterways year-round. Oftentimes, spikes in road salt concentrations are recorded in the spring after snowmelt and again in fall after large rain events. These weather events "flush out" remaining road salt residue. To monitor these spikes, volunteers will continue monitoring road salt concentrations through November 2022. Please see below for a brief summary of volunteer findings thus far.
As a partner of the Izaak Walton League of America (IWLA), ACD has also been uploading these results to their Salt Watch Results Page.
Stay tuned as the year continues!