Wednesday, March 27, 2013

Where is our water going, revisited.

Awhile ago, I wrote a post about where our water is going (the major water withdrawals in Wisconsin).  However, recently, there have been multitudes of articles from all around the Great Lakes about low water levels and the challenges that they bring.
Lakes Michigan and Huron broke previous low water levels in January. Superior is currently just slightly under last year's average and about a foot under the long-term average (US Army Corps of Engineers).  In Michigan, coastal towns are facing huge economic losses due to shallower harbors and the need for additional dredging.  The Michigan legislature actually just approved $21 million in additional dredging funding last week.  So where is the water going and do we need to be concerned?
There are a lot of factors that impact lake levels.  Dredging channels out of the Great Lakes basin (like the St. Clair River) so that it is deep enough for large ships allows more water to flow out of the Great Lakes.  Obviously, rain and snowfall impacts the lake levels as well.  Evaporation is thought to be a major cause behind the current low lake levels (see a great article about it here).  Basically, with less ice on the lakes in the winter (we know that Lake Superior has lost over 70% of its ice since 1970), there is more evaporation.  There is less ice because the air and lakes are getting warmer. 

Should we be concerned about this?  Low lake levels are definitely a cause for concern, as citizens and businesses on Lakes Michigan and Huron are currently seeing.  Boats can't get into some harbors without dredging, leading to lost profits for the harbor and the community. Dredging itself has some issues, like stirring up contaminated sediment.  Also, large ships have to carry less cargo on each trip and make more trips, which costs more.  There are many other impacts of low lake levels as well.  You can stay informed about lake levels as well as other news from around the region with GLIN Daily NewsGreat Lakes Echo is also a great resource for Great Lakes news.

-Written by Jillian Schubert Edwards

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