Catch basin. Photo taken in Grandville, Michigan; January 3, 2013.
Winter in West Michigan. Snow and rain have both produced ice in the cold weather this year. Runoff is always a concern with rain, but snow and ice contribute equally as much to the problem when they melt, if not more. The added concern for water quality in winter is the application of salt to our roads and sidewalks to melt ice and prevent dangerous buildup.
A Slate article from 2010 points out that 13 times more salt is used on our roadways each year than by the food processing industry, and it comes with numerous problems for our water systems. It can make drinking wells salty tasting, disrupt aquatic species, and create dead zones in water bodies. In 2009, the Great Lakes Echo reported on a study saying these are problems for the Great Lakes.
So, why do we keep using salt? The Slate article says:
Because it’s cheap. Alternative chemicals can be much more expensive… and they often require municipalities to invest in new spreading equipment. Plus, replacements can come with their own environmental issues. … So far, no one’s invented a completely benign way to get ice off the roads—except, perhaps, the shovel.
Road salt might not be going away soon, but it’s something we should all be aware of, especially those of us who may use it ourselves.
For more information, the Minnesota Pollution Control Agency has an informative page for road salt and water quality, and the Southeast Michigan Council of Governments has a fact sheet, “Salt Storage and Application Techniques” (PDF).