As another round of snow and ice hits this winter, the old response may have been to reach for the bag of road salt. New tactics promoted by our region’s Pollution Control have been changing facility and road crew tactics.
There’s growing awareness of the harm it can cause to freshwater resources – wreaking havoc on aquatic life, disrupting ecosystems, making its way into groundwater and corroding pipes.
Chloride levels in the portion of the river that runs through the Twin Cities metro area increased 81% between 1985 and 2014, according to a 2016 report from the nonprofit group Friends of the Mississippi River.
Environmental experts state that we clearly can’t sustain a 1% to 4% yearly increase. This form of freshwater contamination is unique to the upper Midwest though its impacts are felt in the Gulf.
Toxic amounts of chloride can kill freshwater aquatic plants and animals. That includes zooplankton, microscopic animals that feed on algae. Leading to die-offs ultimately creating harmful algal blooms, which have adverse effects.
Though the Mississippi River is at this point under the limit, many smaller tributaries are not. In Minnesota, 50 lakes and streams are considered impaired by chloride, and another 75 have chloride levels near the standard, according to the state’s pollution control agency.
In Wisconsin 51 lakes are at or above the standard.
Smart salting (appropriate volume of salt at the given time), using beet juice to lower freezing temp, and pre-mixing solutions can decrease the amount of salt used.
I’ll leave you with something to season future winter weather conversations; extreme weather and icy precipitation are predicted to worsen with climate change. Few, if any weather conditions stop modern trains – the river already has two rails serving its communities. A water quality, climate, transit and solution for the north – in one fell swoop?
Lake Pepin Legacy Alliance (LPLA) advocates for upstream sediment reduction and local lake management to improve water quality, habitat, and accessibility in this vital stretch of the Mississippi River. For more information, including full blog posts, subscribe to our newsletter: www.lakepepinlegacyalliance.org/newsletter