Where did the water go?

Fall-Winter 2007

Beaver Island shoreline property owners (anyone who visits our beautiful beaches, for that matter) have watched with dismay as the water level in Lake Michigan has dropped steadily and dramatically for the past several years.

Theories about why this is happening abound, the most comforting among them being that it is a cyclical process and sooner or later the water will rise as it has historically. But two factors that have not been part of the long-range historical picture cause concern that past cycles may not repeat themselves.

First, of course, is global warming and its byproducts: less precipitation, especially in the form of snow, and greater evaporation over the vast surface expanse of the Great Lakes resulting not only from higher temperatures during the warmer months but especially from the lack of ice cover in the winter.

Second, and new to the public conversation since this past summer, is the accelerating loss of water from Lakes Michigan and Huron through the so-called St. Clair River “drain hole.” It turns out this has been a matter of recognized official concern for at least eighty years. The International Joint Commission issued an “Order for Mitigation” for the St. Clair River in 1917. That order still stands, not having been superseded by any later bi-national agreement, but never has been implemented.

The condensed version of what seems to have happened in the St. Clair River is that as a result of dredging to accommodate ocean-going freighter traffic many years ago, much of the protective layer at the bottom of the river was lost and in many places the material at the deepened river bottom has dislodged and washed downstream, leaving the river as much as twice as deep as it needs to be for such maritime commerce in many places.

It has been known for many years that the difference in water levels between Lake Huron (which is the same as Lake Michigan) and Lake St. Clair have been steadily and rapidly shrinking. Over the past several years, as the Huron-Michigan water level has dropped, the levels of Lakes St. Clair and Erie have risen. For some time the constituent national bodies in the International Joint Commission (Environment Canada and the U. S. Army Corps of Engineers) attributed that to weather differences in the lake basins (roughly, that it rained more around Lakes St. Clair and Erie than it did around Lakes Michigan-Huron). But a rigorous scientific study by an internationally respected hydrological firm, Baird & Associates (commissioned by the Georgian Bay Association, from whose newsletter most of this account is drawn) disproved that.

In mid-2005, after being presented with all the findings of the Baird report, one of the co-chairs of the International Joint Commission announced that he was convinced it was valid science and sufficient cause to further investigate the erosion problem in the St. Clair River. As a result, a new first phase was added to a pending Upper Great Lakes Study: examination of St. Clair River erosion and potential mitigation measures. That still has not happened, however, because Environment Canada would not allocate the Canadian portion of funding for the study. Funding finally was approved for the first two years of the project, and it recently was announced that timing of the St. Clair River study has been moved up for completion in early 2009. But in the meantime it is estimated that 2.5 billion gallons of water leave Lakes Huron-Michigan every day – three times more than was thought to be the case until quite recently.

Two types of remediation are contemplated: placing large rocks in the deepest “holes” in the river to stop further erosion in those areas, a fairly “low-tech” measure that could be accomplished rather easily and inexpensively; and eventually designing and building permanent variable control structures that would “hold back” some of the St. Clair River outflow from Lakes Huron-Michigan. (According to the Georgian Bay Association, preliminary designs for such structures were developed by the International Joint Commission after Lake Michigan-Huron water levels reached all-time lows in the mid-1960s, but as the lakes rose again over the following twenty years they stayed on the shelf without further development.)

Some folks advocate for dumping rocks in the parts of the St. Clair River already known to be the deepest now, without waiting for a complete three-dimensional analysis of the contours and flow characteristics of the entire river. A friend of mine who has a cottage on Lake Huron in the Upper Peninsula (and is former statewide chair of the Michigan United Conservation Clubs) has been writing letters to that effect to politicians and the Corps of Engineers.

Whether or not that is a good idea, it seems like a very good idea for everyone who is concerned about this issue to communicate such concern to all our elected representatives (and to the International Joint Commission, www.ijc.org) and demand prudent, decisive and expeditious action before we lose any more water and gain any more unwanted expanses of beach. I plan to do so, both personally and as a spokesperson for BIPOA, and I encourage all BIPOA members to do the same.

– Paul Glendon