Businesses on the banks of the Great Lakes are flailing in shallow waters this year. Hundreds of marinas either have had to haul boats into winter storage early or have lost mooring space. The team at Great Lakes Marina in Muskegon, Mich., has had to rescue boats that have run aground almost every week since July.
Great Lakes Marina general manager Jeff Covey reported eight large boats that normally dock at his marina have not been able to get into the low waters there. That has cost him $30,000 in revenue, and he expects to incur more expenses from damage to his docks. "Our docks are not designed for waters to be this low," he said. "We have floating docks that are so low down in the water that they have pulled away from our sea walls, which is going to cost about $30,000 to $40,000 to rebuild for next year."
Matt Fogg, owner and operator of St. James Marine Co. and Fogg Towing on Beaver Island, Mich., has had trouble moving his boats in the past couple of months. "I've noticed with our tugs, we've had a difficult time getting around the harbors. Where we used to go earlier, we're now always getting stuck in the mud," he said. He's also had to carry less freight on his barges due to the low water levels.
Water levels in the Great Lakes have been falling all year and on two days in October skimmed levels that are record monthly lows. "We've seen very much below average levels, but we have not set historical lows yet," said Keith Kompoltowicz of the Detroit watershed hydrology branch of the Army Corps of Engineers. Kompoltowicz attributes the fall to the hot, dry summer and the dry winter.
The mean October water level in Lake Michigan-Huron stood at 576.57 feet -- 5 inches lower than the September average, more than a foot lower than the average in October 2011, more than 2 feet lower than the long-term average and just 2 inches above the record low that the lake sank to in 1964.
An inch of water lost from Lake Michigan-Huron is 790 billion gallons of water missing.
There's little respite coming for Covey and Fogg. It may not have happened yet, but Lake Michigan-Huron is all set to touch and maybe even dip below its historical lows. A graph of the latest six-month forecast by the Army Corps shows that, from November on, the range of predicted water levels sits astride the line marking record minimums for the lake. This means the water level will most likely be a couple of inches above or below the record low for the next six months, depending on the weather.
The forecast mean level for November is 576.38 feet, an inch above the record low. December levels are forecast to tie the record, and January and February averages will most likely be never-before-seen slumps.
Meanwhile, the levels for Lakes Superior, St. Clair, Erie and Ontario should remain below their long-term averages but hold above historical lows.
Computer models clash over the future
The drought that has haunted most of the Midwest and Great Lakes states has been the major culprit responsible for the receding waters. Some aspersions have been cast on past dredging and diversions of lake water. John Allis, chief of the Great Lakes hydraulics and hydrology office of the Army Corps, thinks the impact from dredging is nowhere close to the effect that climate has had on the lakes.
"Really, what's driving the water levels is the weather right now. Since those dredging projects, the lakes have set record highs," Allis explained.
What is less obvious is what a future with climate change is going to hold for the lakes.
In a study released earlier this year, the International Joint Commission, the binational body that regulates the lakes, said "despite best efforts, the lake levels remain almost entirely unpredictable more than a month ahead." Global climatic models introduced more uncertainty into the study, and the use of regional climatic models did not throw up the full range of impacts.
In a 2010 study, Jim Angel, state climatologist for Illinois, analyzed climate models using different temperature and precipitation scenarios till the end of the century. Using this information, he built hydrological models of the Great Lakes and the water levels for each scenario.
"The problem was some models were drier and some were wetter. The disappointing thing about the actual study is that some showed a rise in Great Lakes water scenarios, and some showed a decrease."
Drought and lack of ice cover
Precise answers have been elusive in other studies, too. Speaking at a panel at Northwestern University earlier this month, Don Wuebbles, professor of atmospheric science at the University of Illinois, pointed out that a series of analyses over the years predicted future levels to be in a range of 6.5 feet lower to a potential increase.
Wuebbles conducted a study himself that showed Lake Michigan would see a fall of only 1 to 2 feet. He cited even more recent studies based on analyses of evapotranspiration from the lakes' surface that show the fall would only be a few inches.
One thing is clear, though. Lake evaporation is increasing and will increase for the foreseeable future spurred by lack of ice cover, increasing surface water temperatures and wind speeds, according to the International Joint Council study.
The study also found that at present, evaporation in Lake Michigan-Huron is being offset by precipitation, but that hasn't happened in Lake Superior for the past 60 years, resulting in less water in the entire basin.
Covey has spent more than two decades at Great Lakes Marina but has never seen waters so low. "Lake Michigan has been losing water for years," he said. "It used to run in cycles, but for the past three years it's been lower than ever. But I've never seen it this low in my lifetime, at least."
There is only one remedy, according to Kompoltowicz. "We would need a winter with plenty of snowfall and springtime with slow runoff of water built up in that snow coupled with heavy rain. And we would need a couple of winters like that to get back to average water levels."