Water Levels and Flows
Study says drop in lake levels natural, no need to act
In May, an International Joint Commission’s study board released a report asserting that relative changes in the levels of Lakes Michigan-Huron and Lake Erie since the last major dredging of the St. Clair River in 1962 is not the result of human activity.
This report has set off a new round of controversy about whether actions should be taken to control the flow of water through the St. Clair River in order to make water levels higher in Lakes Michigan and Huron.
The IJC’s International Upper Great Lakes Study Board’s draft report “Impacts on Upper Great Lakes Water Levels” [www.iugls.org] found that the difference in water levels between Lakes Michigan-Huron and Lake Erie was 23 centimetres (9 inches) less in 2006 than it was in 1962. They found that this relative change is the result of a major erosion event in the mid-1980s – possibly as a result of an ice jam in 1984 – climate change, and the on-going rebound in the earth’s crust as a result of the glacial retreat 10,000 years ago.
Because the changes since 1962 are not the result of human activities, the IJC’s Study Board concluded that no actions should be taken now to restore or protect water levels on Lakes Michigan and Huron.
The Georgian Bay Association Foundation says that its assessment of the IJC Study Board’s data and the data of some consultants shows that the change between 1962 and 2006 is substantially more – at a minimum 50 percent more. They also bring forward evidence about on-going erosion in the St. Clair River that is making the disparity in water levels between Lakes Michigan-Huron and Erie ever greater. This relative dropping of water levels in Lakes Michigan and Huron is resulting in major loss of wetlands, especially in Georgian Bay.
The GBA Foundation objects to the IJC Study Board’s recommendation not to consider remedial action at this point to protect Lakes Michigan and Huron. They assert that the damage is ongoing and increasing; therefore, there should be no further delay in determining what actions could be taken and implementing these actions quickly, after an appropriate assessment.
Other environmental groups have not yet commented on the IJC study board’s report because the supporting data has not yet been released by the Study Board. The Alliance for the Great Lakes, Great Lakes United and the National Wildlife Federation have raised alarm that it’s impossible for them to carry out thorough assessments because the full scientific and technical reports supporting the IJC’s report and peer reviews have not yet been publicly released. The IJC has indicated that it will extend the public comment period to allow time for the release and review of these reports.
This report on the St. Clair River is part of a five-year study being carried out by the IJC on water levels on Lakes Superior, Michigan, Huron and Erie. By the end of the study, they will decide whether changes should be made to flows of water from Lake Superior to Huron through the St. Marys River.
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© 2009 Great Lakes News. 
We have listened to report after report from the IJC with dissatisfaction.
We have lived on the shores of Lake Superior & have owned property here since 1968. We have never seen low water like we have had for the last 5 yrs. or so.
The last 3 winters we have had plenty of snow. We get plenty of rain. Two years ago we had 12 inches in one night from the Sault to Pancake Bay and we still see low water and property devaluation.
Every spring we read that Lake Superior is so much lower than last year. Yes Lakes Michigan & Huron also record some loss but Superior always has the greatest loss. So what do they do? They give Mich. & Huron more from Superior.
It seems they follow the same practice every year no matter what the levels are.
Can they not control these outflows according to the levels at the time? Must they follow the same practice every year because this is what’s been done for many years?
Even a Beaver knows what to do!!