By Joe Knaeble, Master Water Steward and member of Stop Over Salting
Keep your sidewalks safe with less salt and protect our water.
Sodium Chloride, NaCI, is the most commonly used deicer and it’s the chloride part that is permanently polluting the Chain of Lakes, Minnehaha Creek and many other water bodies in the metro area. Sodium Chloride is commonly called rock salt. It melts ice and snow, down to about 15 degrees, and then dissolves into the melt water, flows into the storm sewers and into our lakes, creeks, wetlands and rivers. Seventy percent of it stays in our local water bodies and there is no practical way to remove it. The only viable solution is to significantly cut back on using chloride as a deicer.
A solution of 270 mg/LT of chloride in water is considered impaired. In Minnesota, 54 lakes or streams are already considered impaired, many of them in the metro area, with more on the way. As the levels of impairment rise, the ability of our water to support the aquatic food chain diminishes. Fish, plants and microorganisms are already being negatively affected. On land, chloride causes millions of dollars of damage to local infrastructure (mostly concrete and steel), harms plants and trees, affects soil’s ability to retain water and hold minerals, irritates your pet’s paws and can make them sick by ingesting it. It is also already impairing some aquifers where some communities get their drinking water.
Best Practices For Significantly Reducing Use Of Chloride Deicers
Shovel, Scrape, Repeat
Don’t Let Snow Get Compacted
Choose The Right Tool
If You Use Salt, Only Use It On Ice & Slippery Spots!
Use Grit Or Sand For Traction Instead Of Salt For Deicing
Use The Recommended Amount Of Deicer (MPCA says 1# per 250 s.f. (10 oz. coffee mug)
Tools and Equipment Tips
A scoop shovel is for lifting and throwing snow and should be light.
A push shovel pushes snow down the sidewalk, scraping down to the pavement and should have a hard steel edge.
Scrapers and ice chisels can lift or break up compacted snow and ice.
If your snow blower does not clean down to the pavement, follow with a push shovel.
Less is more when using chloride
Over-applying deicers does not create more safety but does create more pollution.
If you use chloride products, the recommended spread pattern is one grain every 3 inches. Re-shovel the ice and compacted snow after the deicer loosens its bond to the pavement or it will refreeze
Magnesium chloride and calcium chloride are two deicers that work below 15 degrees but they still have similar negative effects because they contain chloride. They often come in a mix with sodium chloride. If you use them use the same spread pattern (one grain every 3 inches) and only use on ice and slippery spots.
If you see salt on dry pavement, it’s over applied. Sweep it up. Reuse or put in the garbage.
Sweep up left over sand or grit and reuse.
Other resources
The Chloride page on the Minnesota Pollution Control Agency website
The Snow and Ice Removal page on the Mississippi Watershed Management Organization website
