Chloride and Lake Independence
by Pat Wulff, Founding Board Member
Once Chloride gets in our surface or ground waters there is no way to remove it, and over time a lake will no longer be able to support native plant and animal life. Melting snow and ice will carry road salt directly into our surface waters. This salt accumulates, year after year, and there is no known treatment to remove it. Water softener salt travels to our municipal treatment facility; where the still salty water is discharged to the environment and accumulates in ground or surface waters. There are now at least 50 MN lakes and streams that are above the 230 mg/L legal EPA standard to be listed as impaired and 75 lakes on the at-risk list. The good news is that Lake Independence is in no immediate danger of getting put on either list. As a matter of fact, no one is monitoring Independence for chloride, and there seems to be a very good reason.
The good new. Brian Vlach, 3R Senior Resources Manager, told me they haven’t been monitoring chloride on Independence because there most likely isn’t a chloride issue. Usually, high salinity and conductivity concentrations are a sign that there is a chloride issue. The temperature – dissolved oxygen and conductivity measurements that we have been collected bi-weekly from the surface to bottom at 1-m intervals doesn’t suggest that there are any issues. Most of the lakes within agricultural rural watersheds haven’t had chloride impairments. You start to have problems when the watershed becomes more developed.
More good news. Minnesota is the first state to have a statewide chloride management plan developed by the Minnesota Pollution Control Agency (MPCA). The MPCA has an educational video “Improved Winter Maintenance: Good Choices for Clean Water”, that it has requested lake associations show their members. You can find this video and more at the MPCA’s Chloride website: https://www.pca.state.mn.us/water/chloride-salts. If you want to dig deeper, you could read the https://www.pca.state.mn.us/water/draft-statewide-chloride-management-plan .
More good news, the cities of Independence and Medina road management crews have taken training and passed road salt management classes. These classes are repeated annually. Their goal is to protect water quality, while using the least amount of salt. Using less salt also saves a lot of your tax dollars.
More good news is you can join the fight to stop chloride pollution, by doing some of the following:
When Clearing Winter Walks:
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Watch the suggested videos and share the information with others.
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Shovel early and often, use an Ice chisel for ice, use sand for traction, and you may not need salt.
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More salt does not mean more melting. Go lean a coffee mug is adequate for a 20-foot driveway or 10 sidewalk squares. Use a handheld spreader to help apply it consistently. The individual grains should be about 6” apart.
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Wait for warmer weather, salt does not work at Temperatures below 15 degrees.
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Sweep up extra salt. If its on dry pavement, its not doing anything good and will be washed into waterbodies.
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Slow down, drive for the conditions, avoid unnecessary travel. and consider buying snow tires.
When considering, choosing, or using a water softener:
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Change from a timer-based to an on-demand-based softener. It could save up to 60%
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Lengthen the cycle if you have a time-based system see if you can extend the time between cycles.
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Don’t over soften. Check your unit’s settings. It may have been set at an unnecessarily high at the factory.
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Only soften the water that needs it, not to outside spigots or for drinking water.
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Investigate lower-salt methods. Pre-filters can be used to remove iron, manganese and hydrogen sulfide without help from water softeners.
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All softened water contains salt and ends up in the environment. Let’s all think of ways to use less.