Lake Huron water levels sinking towards record low

[Spiel]

Lake Huron water levels sinking towards record low

manitoulin.ca

Week of January 2nd 2008

 

 

 

As December drew to a close, the level of the continent's second-largest lake was within a couple of inches of its all-time low, and experts fear that the lake could dip below that dubious mark as early as this month.

 

"We have been below what the International Joint Commission considers a crisis level for six to seven years now," remarked Mary Muter, chair of the Georgian Bay Association's environment committee. "And now it looks like we'll be setting record lows in January."

 

The lowest reading so far occurred in 1964, when the lake dwindled to 175.62 metres (as expressed in height above sea level). That was nearly a metre below its long-term average, and almost two below the record high measured in 1986.

 

As December began, Huron was just eight centimetres above this historic ebb. As of press time, that buffer had been reduced by half, putting us just four centimetres away from an unprecedented plunge.

 

The December issue of 'Level News,' Environment Canada's monthly bulletin on Great Lakes water levels, focussed almost entirely on the looming crisis faced by Huron and Michigan, which function as one system since the two lakes are conjoined.

 

"Although it is too early to say just how large the 2007-'08 seasonal declines will be on each of the lakes, it is probably safe to say that anyone affected by, or interested in, water levels on Lakes Michigan-Huron is watching this year's seasonal decline very closely," the bulletin states.

 

Conditions were dry in November, with increased evaporation and water supplied to the pair of lakes approaching record-low proportions, according to Environment Canada. "As a result, daily water levels on Lakes Huron-Michigan fell 13 centimetres during November, eight centimetres more than their (usual) decline for the month."

 

As December began, the level of both lakes was 66 centimetres less than normal for this time of year. Barring a deluge of precipitation or sudden gift of overflow from Superior, the federal agency was anticipating that "levels on Lakes Michigan-Huron could begin 2008 as low as they were in 1965," with "new record lows (to) follow if low water-supply conditions persist."

 

Ms. Muter said that some residents of Lake Huron are already pronouncing a record low, based on "the markers they have on their docks to track water levels." And one government gauge on Lake Huron has already registered a single-day reading that was below the all-time dip, according to a Michigan newspaper; it doesn't stand as the record, though, because to do so the same measurement (or a lower one) must be sustained over a one-month period.

 

But even if the lake retains a bit of a technical cushion above its record low for now, riparian dwellers like Ms. Muter are feeling anything but reassured. "The US Army Corps of Engineers is saying that we'll be 15 inches lower in 2008 compared to 2007," she said. "Projecting into next summer, we could be a foot lower than last year."

 

Low water has significant economic consequences for shipping companies, which are forced to lighten the loads of freighters, but also for cottagers and marinas, which wind up with elevated docks, exposed water lines, and shallower harbours. A few people might welcome a broader beach, but generally it's bad news, both for the environment and business.

 

"We know already that this is leading to huge applications for blastings and dredgings," said Ms. Muter.

 

Her organization, which represents cottagers across Georgian Bay, has pointed to the lake's outlet via the St. Clair River as one of the key factors in the lowering of Huron. A study commissioned by the group blamed scouring and dredging of the shipping channel at this passage for an increased outflow from the lake.

 

Preliminary findings released this fall by a bi-national group conducting a multi-year study of the upper Great Lakes seemed to refute that claim, based on images recorded by underwater cameras, but Ms. Muter believes that much more analysis needs to be done before the river is ruled out as a culprit in Huron's water woes.

 

"Our basic response has been that to try to draw conclusions from preliminary findings is inappropriate," she said. The footage taken of the riverbed "is kind of like taking a photograph when you need an MRI," she analogized.