The Lake St.Clair Network: Lake levels near record low

Second in a series on the environmental health of the Lake St. Clair basin.

The water levels of Lake Huron and Lake St. Clair are nearing historic lows.

"We're not at historic lows, but we're close to historic lows," said Lana Pollack, U.S. chair of the International Joint Commission, speaking at the sixth Binational Lake St. Clair Conference, held at MacRay Harbor in Harrison Township on Nov. 29 and 30. "There's a 60 percent chance we'll hit it. That's good for phragmites, but not for boating."

On Nov. 30, according to the U.S. Army Corps of Engineers, Detroit District, Lake Huron stood at 576.2 feet. The all time low for Lake Huron is 576.0 feet, set in March 1964.

"Lake Michigan-Huron is 16 inches lower than its level from last year," the Corps reported. "Over the next month, Lake Superior and Lake Michigan-Huron are each forecasted to drop 3 inches from their current levels."

Lakes Michigan and Huron are considered by hydrologists to be the same body of water.

Lake St. Clair stood at 572.6 feet on Nov. 30. The all time low for Lake St. Clair was reached in January of 1936 and January of 1926, when the levels bottomed out at 570.5 feet.

"The water levels of Lake St. Clair and Lake Erie are each expected to decline 1 inch over the next month," the Corps stated.

There has been a lot of speculation over the last few years about the cause of falling lake levels. Are the falling lake levels caused by climate change? Are forces of nature, including the weather, behind the drops? Or are they caused directly by human influences, such as dredging and diversions?

Residents around the Georgian Bay have blamed the dredging of the shipping channel at the mouth of the St. Clair River for much of the decline in Lake Huron. Others have blamed diversions of water out of the lakes.

"One factor that cannot be ignored is the diversion of more than 340 billion gallons of Great Lakes water each and every year through the Chicago Diversionary and Ship Canal," said U.S. Rep. Candice Miller, who represents the Voice readership area, in a Nov. 1 request of the U.S. Army Corps of Engineers to review the diversion, last done in 2009.

Experts at the Lake St. Clair Conference came down on the side of the forces of nature determining the drop, not direct human actions, such as diversions.

The big danger of the Chicago diversion is Asian carp coming in, not water going out, said Pollack.

"The truth of the matter is that diversions add more to the Great Lakes than they remove," said Adam Fox, a water resources planner with USACE.

The Ogoki and Long Lac diversions, which divert water from Hudson Bay into the Great Lakes, pour more water into Lake Superior than the Lake Michigan diversion at Chicago and the New York Barge Canal diversion, located between Lakes Erie and Ontario, take out of the lakes.

"The forces of nature have a much greater impact on the levels of the Great Lakes than human influences," said Fox.

Seasonally driven evaporation plays a particularly key role. The seasonal cycle typically sees snow and ice accumulation in and around the lakes in the winter, increased runoff into the lakes with snowmelt in the spring, increased water temperatures in the summer with the warm sunshine, followed by increased evaporation in the fall due to the warmer water.

"Last year we had a relatively snow-free, mild winter," said Fox.

The lakes were not recharged in the spring because there was little snow to melt. The subsequent drought in mid to late summer hastened the drop in water levels.

"In October, they crashed," Fox said.

Pollack sees climate change, fueled by human activities like gas-powered cars and coal-generated electricity, as the underlying cause of low lake levels.

"We're all dealing with climate change," said Pollack, pointing to everyone from the East Coast victims of Hurricane Sandy to American farmers. "Every one of us is living it."

On the oceans, higher global temperatures mean melting polar ice caps and higher water levels. On the Great Lakes, it's a different story.

Climate change means warmer weather, which means less ice cover on the lakes in the winter, which protects the water from evaporation.

"Less ice, more evaporation," said Pollack.

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