Kallestad column: The Land of Sky Blue Waters
One of the nicknames for Minnesota is the Land of Sky Blue Waters. While this may be a fitting name for some of our northern lakes, we don't often get to see this in southeast Minnesota.
Major algae blooms are common on most of the lakes in the Cannon River watershed each summer. So why does this happen?
It boils down to a serious case of overeating on the part of algae that lives in the lakes and rivers. The algae live on a diet of phosphorus, nitrogen and carbon.
Phosphorus is usually the nutrient that is in shortest supply. When phosphorus gets added to water the algae goes on a binge so to speak.
Estimates are that one pound of phosphorus can result in the growth of 300 to 500 pounds of algae. It's time to put the algae on a low-phosphorus diet!
While some of the phosphorus getting to the lakes and rivers is natural, a lot of it is not. We humans do a great job of adding lawn fertilizer, grass clippings and leaves to the storm sewers that drain to the rivers.
At some point we decided it was a good idea to bring our city landscaping with us to the lakeshore and have destroyed many of the native plants that filter out dirt and phosphorus.
In some cases we have chosen to work the land in ways that result in excessive erosion and have added lots of phosphorus to our fields in the hopes of better crop yields.
We have ALL made a contribution to the problem.
The good news is that we can all be a part of the solution. By rethinking the way we landscape and farm there are many positive choices we can make that will hopefully bring sky blue water to southeast Minnesota.
For more information on how you can do this, visit www.crwp.net or give us a call at (507) 786-8400.