Arkansas researchers study environmental effects of de-icers

Winter road safety depends heavily on salt-based deicers, but there are concerns about how their use is contributing to increased salinity in streams and affecting aquatic ecosystems. Beet brine, which is made from a mixture of salt and beet molasses, has emerged as a potential alternative because it reduces overall salt application. But unlike traditional road salt, beet brine can introduce nutrients such as nitrogen and phosphorus into runoff. 

Researchers from the Arkansas Agricultural Experiment Station wanted to know more about how both deicers affect fundamental stream processes such as the breakdown of leaf litter. They partnered with the University of Notre Dame for a controlled study using artificial water enclosures that simulate natural stream conditions. Maple and oak leaves were exposed to low and high concentrations of road salt and beet brine, and scientists measured microbial colonization and decomposition rates for a two week period to evaluate the effects of each treatment.week period to evaluate  

Contrary to expectations, neither deicer significantly altered overall decomposition rates during the study window. Beet brine slowed early stage decomposition of maple leaves more than traditional salt during the first week, but this effect did not persist. Microbial colonization of oak leaves increased under all deicer treatments, and no meaningful differences were observed between low and high salt concentrations.stage decomposition of maple leaves more than traditional salt during the first week, but this effect did not persist. Microbial colonization of oak leaves increased under all deicer treatments, and no meaningful differences were observed between low and high salt concentrations. 

This research improves understanding of the ecological tradeoffs between conventional deicers and those promoted as eco-friendly alternatives. The findings support winter road management strategies that prioritize “smart salt” practices — using deicing solutions only when necessary — to minimize runoff, protect water quality and maintain road safety. 

Arkansas Agricultural Experiment Station | Project supported by state appropriations; Hatch capacity funds. Photo courtesy of University of Arkansas System Division of Agriculture.