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Lake Michigan Levels May Fall to Uncharted Territory

January 3, 2008

JACKSONPORT, Wis. – It was a different story when the first “polar bears” took to the frigid New Year’s Day waters in Jacksonport 22 years ago.

It was 1986, and Lake Michigan was at its historic peak, about 6 feet higher than it was on Tuesday morning. But that’s just a number.

To get an idea of how much things have changed since then, consider this: Firefighters this year had to string yellow caution tape stretching from the icy shoreline into the lake to protect participants from stepping on … a shipwreck.

“I don’t think I’ve ever seen it this low,” said 65-year-old Jacksonport Fire Department volunteer Al Scharrig, standing in a cold water rescue suit about 50 yards from the Door County shoreline and still in only shin-deep water.

National Oceanic and Atmospheric Administration water gauges showed that on Christmas Eve the surface of the lake had dropped to about 575 feet, 9 inches above sea level. The record low for the lake, set in April 1964, is actually a few inches above that.

Because hydrologists use monthly averages to set lake level records, nobody at this point is saying the lake officially hit an all-time low. But Lake Michigan is now about 2 { feet below its long-term average, and water experts said it might be only a matter of weeks before levels dip into uncharted territory.

The lake typically drops in winter, but Army Corps of Engineers officials said forecasts calling for less-than-average precipitation in the next two months coupled with above-normal evaporation rates mean the lake likely will drop a half-foot more than normal before it begins to rebound with the spring snowmelt.

“There is a high chance in setting record lows in the next couple of months,” said the Army Corps’ John Allis.

This is troubling news for a number of reasons, said the region’s mayors.

“As you are well aware, the economic, environmental and social impacts of declining lake levels are already being felt by many, including commercial fisheries, marinas and shippers as well as recreational enthusiasts, property owners and municipalities,” Racine, Wis., Mayor Gary Becker wrote on Dec. 19 to the International Joint Commission on behalf of the Great Lakes and St. Lawrence Cities Initiative. The initiative is a coalition of mayors from dozens of lakeside cities, including Milwaukee, Chicago and Toronto.

The commission is a binational body that oversees U.S. and Canadian boundary waters issues, and it is in the middle of a multiyear study exploring the causes for the decline in water levels on Lakes Superior, Michigan and Huron. Potential factors include changes in precipitation and evaporation rates, as well as human manipulation of the rivers that drain the lakes.

Another possible cause is the Earth’s crust continuing to rebound since the retreat of the glaciers, essentially pushing water out of the lakes and ultimately into the Atlantic Ocean at a faster rate.

The mayors want answers fast, and even a possible fix for Lakes Michigan and Huron. That would likely require some type of dam like structure to slow the flow of water on the St. Clair River, the main outflow for the two lakes, which are one body of water connected at the Straits of Mackinac.

Michigan Gov. Jennifer Granholm asked the Army Corps in October to begin designing such a structure. The Great Lakes Commission has made a similar request.

Such a project could insulate the lakes from dramatic drops, but it could pose problems on downstream Lakes Erie and Ontario, and their connecting waterways. There are also concerns that plugging the river could cause big trouble if and when Lakes Michigan and Huron rebound toward record levels.

The mayors’ biggest worry is the so-called drain hole theory on the St. Clair River, which was heavily dredged in the early 1960s as part of the St. Lawrence Seaway project to open the lakes to oceangoing vessels.

The Army Corps at the time knew the dredging would drain the lakes at a faster rate, and predicted that the project, combined with earlier riverbed tinkering, would lead to a permanent loss of about 16 inches from the long-term average on Michigan and Huron. The Army Corps planned to install some type of water-slowing structure in the river to restore lake levels after the dredging, but never did.

A group of Canadian property owners, meanwhile, contends its studies show that riverbed erosion since the 1960s has led to even more water flowing down the St. Clair, and the actual drop in the averages of Lakes Michigan and Huron is closer to 3 feet.

The International Joint Commission said this fall that a new survey of the river bottom gives it confidence that there is no ongoing erosion, but said questions remain whether the river channel had eroded in the four decades since the dredging occurred. It intends to get to the bottom of the issue within about a year. It can’t happen soon enough for the mayors.

“It is essential that an assessment of the impact of erosion on water flows in the St. Clair River be conducted in an objective, transparent and timely manner to the satisfaction of all parties,” Becker writes. “Above all, we would ask that the IJC provide its advice to the Canadian and U.S. governments as soon as possible so that any decision on necessary actions to regulate water levels in the upper lakes may be taken without further delay.”

Becker said the mayors decided to speak up after realizing the issue is not getting the attention it deserves from lawmakers.

“People sometimes do wonder: Why are the mayors getting involved in this? Well, we’re the ones who sit on the lakes. There is not a single state capital on a Great Lake. And Washington, D.C., certainly doesn’t wake up in the morning saying, `Hey, we’ve got to worry about the Great Lakes.’ … It’s our job to elevate the issue.”

Levels on Lakes Michigan and Huron have never been constant since record keeping began in the mid-1800s. The water level has fluctuated by about 6 feet between its record peak and low, but severe swings have historically occurred over several years or even decades.

The recent drops have been precipitous. In just the last 12 months, levels have plummeted about a foot and a half.

“That is pretty significant,” said Cynthia Sellinger, a hydrologist with the NOAA.

Yet until the lake crosses its record-low threshold set in 1964, people can at least take solace in the notion that things are still within the normal range, that things have been worse. But once the lake dips below its all-time low, the next question is: Where will it stop?

Becker said some cities are already crafting plans to relocate their drinking water intake pipes.

Sellinger said the low lake levels might well be something people have to get used to, and not just because of what might have happened on the St. Clair River bottom.

She recently co-wrote a study that looked at precipitation and evaporation levels over Lakes Michigan and Huron, and she discovered a worrisome trend tied to increased temperatures in the region over the past few decades. She said precipitation since 1978 has declined and evaporation has increased to the point where, essentially, the sky over the lakes is now taking more water from them than it is giving them.

“Things are warming, and we’re getting more evaporation, and that means lower lake levels,” she said.

Sellinger said her research showed a similar situation in the 1930s and the 1960s when the lakes also shrank dramatically. They also rebounded quickly. She said only time will tell if what has happened is just part of the normal cycles.

“That’s the biggest question,” she said. “Is this going to continue?”

Door County polar bear Chet Bergstrom is a little nervous about where things might be headed, but on Tuesday he chose to look at the bright side.

“There’s still enough water out there to jump into,” he said, “and that’s what is important today.”




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