Snow Removal and Salt
Winter in Minnesota means using salt on slippery roads and sidewalks. When snow and ice melts, most of the salt and sand washes into lakes and streams. Once in the water, there is no way to remove salt. The salt that does not wash away soaks into the ground and damages plant life.
- aquatic organisms
- community structure in aquatic environments, such as diversity and productivity
- terrestrial birds (possibly leading to death)
- terrestrial plants
There are many ways to reduce salt use while maintaining high safety standards. Follow these simple rules to protect our clean water:
- Shovel! When you remove snow and ice manually the more effective salt can be. If possible, keep up with any major storms by doing a little at a time.
- Shovel more! Break up ice and decide if application of a de-icer or sand is necessary to maintain traction.
- Use salt sparingly. As a general rule, use no more than four pounds of salt per 1,000 square feet (an average parking space is about 150 square feet). One pound of salt is approximately a heaping 12-ounce coffee mug.
- Don’t use salt when temperatures fall below 15 degrees (Fahrenheit). Salt stops working around this temperature. For traction use sand. Some de-icers do work in colder temperatures. Check the product’s “practical melting point” not the “eutectic temperature”.
- Sweep up extra. If salt is visible on dry pavement, it is no longer doing any work and will be washed away. Use this salt somewhere else or throw it in the trash.
Plant salt resistant species. The University of Wisconsin provides a great list to help you find a species of tree that is resistant to salt injury. Click here to go to the University's web page.
Know your salts. Salts can range from simple table salt to calcium chloride. Salts are used due to their ability to decrease the freezing point of water. Using calcium chloride is less harmful to the environment than sodium chloride (rock salt), but it is also more expensive. Whatever product you chose make sure you know at what temperature it won’t work. Many labels refer to the “eutectic temperature”, but it is important to use the “practical melting temperature.” If it is too cold for salt to work, use sand instead.
Use this reference guide to help you know what de-icer to use.
|Melting Agent||Freezing Temperatures||Environmental attributes|
|Sodium Chloride||15o F||Cyanide and significant negative environmental effects|
|Calcium Magnesium Acetate (CMA)||22o-25oF||Less toxic|
|Calcium Chloride||-25oF||No cyanide, lower quantities needed|
|Urea||20-25oF||Excessive nutrients, less corrosion|
|Other options and when it's too cold!|
|Sand||No melting effect||Accumulates in streams and lakes|
A great overview of good residential snow and ice practices, courtesy of the Mississippi Water Management Organization: