Editorial Keep lakes on a low-salt diet this winter
You’ve heard about the health risks of consuming too much salt.
Here’s the problem, according to the MPCA: Winters in Minnesota bring slippery roads, parking lots and sidewalks as well as the application of de-icing materials to keep these surfaces safe and ice-free. Road salt, which contains chloride, is the most commonly used de-icer. Chloride from road salt enters lakes, streams and groundwater after snow melts. Once in the water, it becomes a permanent pollutant and is harmful to fish, insects and plants.
The chloride that enters surface water is eventually carried downward into the aquifers that provide the state’s drinking water, and it can even change the taste of tap water.
Over the past five years, the MPCA has assessed the condition of Minnesota’s groundwater as part of the agency’s overall vision for clean water. A chloride study determined that one-third of the wells across the state show an increase in chloride concentrations. In the metro area, 27 percent of monitoring wells in sand and gravel aquifers had chloride concentrations that were greater than drinking water guidelines set by the Environmental Protection Agency.
“Salt is a real threat to water quality,” said Brooke Asleson, chloride project manager at the MPCA. “It only takes one teaspoon of road salt to pollute five gallons of water. If chloride continues to increase in groundwater, more waters will likely exceed drinking water and water-quality standards in the future. We are trying to spread the word that less is more when it comes to applying road salt because at high concentrations, chloride can harm the fish and plant life in our waters.”
There are some steps residents can take this winter to reduce the amount of chloride that gets into our lakes. The MPCA offers the following advice:
Shovel first. The more snow and ice you remove manually, the less salt you will have to use and the more effective it can be. Then, break up ice with an ice scraper and decide if application of a de-icer or sand is even necessary to maintain traction.
Slow down. Drive for winter conditions, and be courteous to slow-moving plows. The slower they drive, the more salt will stay on the road where it’s needed.
More salt does not mean more melting. Use less 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. And be patient: salt takes time to work. Applying more will lead to unnecessary contamination.
A temperature of 15 degrees or colder is too cold for most salt to work. Most salts stop doing their job when the temperature is below 15 degrees. Instead, use sand for traction in frigid conditions.
Sweep up extra salt. If salt or sand is visible on dry pavement, it is no longer doing any work and will be washed away. The excess can be swept up and reused for the next snow or disposed of in the trash.
FORUM NEWS SERVICE