Groundwise: Caring for our water and grounds.
It is winter, and the snow and ice are on the way. Unfortunately, the ways many of us reduce ice from our sidewalks and driveways can create real problems for our watershed. Most sidewalk salt contains sodium chloride. When the salted ice melts, it runs into our streams, rivers and lakes, where the chloride continues to accumulate in the environment over time.
Bad for humans. The Minnesota Pollution Control Agency recently found almost 50 bodies of water in Minnesota that tested above the water quality standard for chloride, 39 of those in the metro area. The data show that salt concentrations are continuing to increase in both surface waters and groundwater across the state. Roughly 75 percent of Minnesotans rely on groundwater for their drinking water, so high levels of salt concentrations are a real problem for human safety.
Bad for wildlife. Chloride in surface waters can be toxic to many forms of aquatic life, including fish, macroinvertebrates, insects, and amphibians. And birds, the most sensitive wildlife species to salt, often mistake road salt crystals for seeds or grit. Consumption of very small amounts of salt can result in toxicosis and death within the bird population.
Bad for fido. Even pets can be harmed by de-icers containing salt. According to the ASPCA’s Animal Poison Control Center, ingestion of road salt by eating salt directly, licking salty paws, and by drinking snow melt and runoff can “potentially produce effects such as drooling, vomiting, diarrhea, loss of appetite, vocalizing/crying, excessive thirst, depression, weakness, low blood pressure, disorientation, decreased muscle function and in severe cases, cardiac abnormalities, seizure, coma, and even death.” (www.aspca.org)
What can we do to help reduce sodium chloride pollution in our watershed?
We each can do our part to prevent chloride pollution by following these simple tips from the MPCP:
- Shovel. The more snow and ice you remove manually, the less salt you will have to use and the more effective it will be.
- Use sand when the temperatures fall below 15 degrees F. Most salts stop working at 15 degrees F. Use sand instead for traction but remember that sand does not melt ice.
- Apply less. More salt does not mean more melting. Use less than 4 pounds of salt per 1,000 square feet. One pound of salt is approximately a heaping 12-ounce coffee mug. Leave about a 3-inch space between granules. Consider purchasing a hand-held spreader to help you apply a consistent amount.
Read more here, and learn more by watching this video, produced by the Mississippi Watershed Management Organization, with tips for homeowners about more environmentally friendly snow and ice removal.
Interested in doing more? If you would like to join Mayflower’s Groundwise team, please contact Linda Ridlehuber (firstname.lastname@example.org).