Low Water Levels in Georgian Bay

Low Water Levels in Georgian Bay
By Judith Grant

Low Water: Water levels in the Bay continue to be alarmingly low. In December the level came within a whisker of dropping below the 20th Century record low of 1963, but then the winter’s plentiful snowfall throughout the Great Lakes Basin rescued the situation, at least temporarily. You can find three authoritative websites for water levels on www.tinycottager.org under Useful Links > Water Levels.

Many complex factors influence water levels. Precipitation, evaporation and the balance of inflows and outflows are the most important. But also, water on the western shore of Tiny Township is becoming shallower as the lake bottom in that area is gradually rebounding from the removal of the immense weight of the glaciers of the last ice age. Surprisingly, this rebound is significant – several inches since the late 1980s.

Low water levels on Georgian Bay north of our area are drying up fragile wetlands upon which 80% of the fish of the Bay depend, making boating channels hazardous, and affecting water quality in long narrow Bay inlets. Low water restricts water mixing and exchange and reduces the dilution and assimilation of lakeshore runoff and effluents. “Nutrients” such as phosphorus build up in the water and sediments cause deoxygenation, making the environment inhospitable for cold water fish. In Tiny, similar problems occur in areas where rock groynes impede mixing and water exchange. In such places, the water temperature rises, algae flourish and give off nasty smells, water clarity diminishes, and E. coli counts rise.

The Baird Report: The Georgian Bay Association (which includes some 4,200 families on the eastern and northern shores of Georgian Bay) felt that the impact of low water was so serious that they went to the huge expense of hiring experts, W.F. Baird Associates Coastal Engineers Ltd., to investigate the causes. Baird concluded that unexpectedly large outflows caused by heavy erosion in the bed of the St. Clair River was producing not just low water, but downward trending water levels in Lakes Michigan-Huron, when levels in Lakes Superior, Erie and Ontario either rose or remained at their usual levels. Dredging for the Seaway in the early 1960s took the depth of the St. Clair River to 27 feet. But Baird found erosion had deepened it at places to 60 or 70 feet in the years since, causing the greatly accelerated outflow from Lakes Huron-Michigan.

The International Joint Commission: With the Baird Report in hand, in 2005 the Georgian Bay Association convinced the International Joint Commission to expand its Upper Great Lakes Study Plan to include St. Clair River erosion. They then lobbied both American and Canadian governments to fund the study and to give priority to the St. Clair River portion of the Study.

Last fall the International Upper Great Lakes Study Board released videos, which purported to show that there is no erosion in the St. Clair River bed. Not so, said Dr. Rob Nairn of Baird. He explained that the IJC had misinterpreted what it saw in the videos, and read the IJC a lesson in the way glacial till riverbeds, like the St. Clair River’s, move. Moreover, the videos were taken at the wrong place, and a comparison of the 2002 to 2005 U.S. Army Corps of Engineers’ depth data showed a loss of 32,000 cubic metres of sediment from the river bottom where the flow is the fastest.

The first of a series of progress reports on the St. Clair River study is due from the IJC later this month. The fieldwork, which began in April 2007, includes cross-sectional surveys of the St Clair River, bed material sampling, videoing the riverbed and preparatory work for a hydrometric gauging station on the St Clair River. A draft report is to be produced by February 2009, rather than 2010 as originally planned. A peer-reviewed final report is scheduled for June 2009.

Diversions and the Great Lakes Basin: Human beings draw great quantities of water from the Great Lakes every day. Cities located on the Great Lakes draw water through long pipes. Deep wells in Michigan have managed to reverse the natural flow of ground water, which normally moves toward Lake Michigan. Bottled water companies draw tremendous volumes from aquifers all around the Great Lakes. But at least this water is returned to the Lakes, after treatment. The Chicago diversion removes 1% of the total water volume of the Great Lakes every year, and sends it, after it has been used, out of the Great Lakes Basin down the Mississippi.

So great has human impact been on the Great Lakes that the eight American states and two Canadian provinces that border them finally reached agreement in 2005 on a Great Lakes-St Lawrence Sustainable Water Resources Agreement. One by one the various signatories to this agreement have been putting the necessary legislation in place to support it. Ohio is still not on side, but it looks as if reason is going to prevail in the end.

Bill 198: In Ontario, Bill 198, which passed in 2007, provides the basis for the legislation needed to support this agreement. Of great importance is the firm stand it takes against diversions of water out of the Great Lakes Basin and between individual Great Lake watersheds. So — no more Chicago diversions. But an ‘Exceptions’ clause, which allows for transfers of up to 19 MILLION LITRES PER DAY from one Great Lake basin to another, remains in the Bill, despite vigorous protests by many environmental groups!

Those working on this issue expect that the Regulations associated with Bill 198 will close this loophole. But the Regulations won’t be completed for some time: in the meantime, work is being done on constraining the “Exceptions” in “Interim Steps”.

Behind the scenes negotiations are ongoing with York Region where developers want to use this ‘Exceptions’ clause to draw water from the Lake Simcoe-Georgian Bay watershed and then pipe the sewage to a treatment plant on Lake Ontario. Word has it that the developers are now looking at other options, and if true, this is very good news indeed.

Damming of wetlands not a solution: Apparently there is a move afoot to dam rivers and streams that drain through the wetlands of eastern and northern Georgian Bay. The idea is that this would keep the water in the depleted, drying wetlands and revive them, but depriving the Bay of inflowing water would lower its level even more. Dams would not get at the root causes of the continuing low water in Lake Michigan-Huron and, by cutting off the wetlands from Georgian Bay, would damage the native fish stocks which need the wetlands at some point in their life cycle. This idea may be floated when the IJC holds a public meeting in Midland later this summer. If it is, it must be firmly opposed.

As you can see, things are in a state of flux. Some recent actions are positive – among them the IJC study, the agreement among eight states and two provinces about sustaining Great Lakes water. Others are anything but positive – the desire of a number of Ontario’s inland cities to draw water from one Great Lake and return it to another and our generally profligate use of a precious resource. As individuals, we need to conserve; as a country we need to work with the Americans in order to manage shared water resources well.