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Great LakesHigh and dry on the Great Lakes
Washington Post, April 3, 2000
The fastest decline in water levels in the Great Lakes in nearly a century and a half is creating havoc for shoreline property owners and marina operators in eight states and two Canadian provinces, and is forcing cargo ships to lighten their loads to avoid running aground. Since the summer of 1997, the middle Great Lakes (Michigan, Huron and Erie) and Lake St. Clair, which connects Huron and Erie, have each fallen 3 1/2 feet and are continuing to recede at a pace that could soon hit all-time low water levels, scientists predict. The five Great Lakes, which do not include Lake St. Clair, are the largest fresh surface-water system in the world. Lakes Huron and Michigan are 13 inches below levels recorded a year ago, and Lake Erie has dropped 11 inches. Controlled by mechanical gates, the waters on lakes Superior and Ontario have, respectively, stayed the same and risen four inches. What the U.S. Army Corps of Engineers calls an ‘astounding’ lack of snowpack runoff this year in the Lake Superior basin, the headwaters for the Great Lakes, has disrupted the lakes’ seasonal replenishment cycle, driving water levels last month in lakes Michigan and Huron down 18 inches from long-term March averages.
Normally, a lake's water level rises in the summer as melted snow flows down the watershed system. The level declines in the winter when snow piles up and freezes in the tributaries, impeding the flow. However, high-altitude aerial surveys conducted last month by the National Oceanic and Atmospheric Administration show almost all of Lake Superiors's shoreline in Michigan, Wisconsin and Minnesota to be snow-free, suggesting that water levels in Lake Michigan and the other Great Lakes fed by Lake Superior will be a foot lower than last year when midsummer measurements are taken. Exacerbating the situation have been lower-than-average rainfall and increased evaporation of surface water during unusually mild winters in the midwestern states. “All of this has thrown a whammy at the replenishment system at large,” said Roger L. Gauthier, supervising hydrologist at the Corps of Engineers' district office in Detroit. “It could be the most radical three-year decline ever.” What makes the current falloff seem so dramatic, Gauthier said, is the contrast between near-record high water levels only three years ago and near-record lows this year. “The Great Lakes are 3,500 years old in their present form, and they have fluctuated dramatically countless numbers of times,” Gauthier said. “The problem here is that it is happening so quickly and it is going from one extreme to the other.”
The most obvious effects of the change here and elsewhere in the Great Lakes are much wider beaches, forlorn-looking boat docks and launching ramps that stop short of the water's edge, new islands popping up out of the receding water faster than they can be named and even the occasional appearance of a 19th century wooden pier that nobody knew was there until the water level dropped. There have also been serious financial consequences, expected to run into the hundreds of millions of dollars. John Rudisell, harbor master in Michigan City, Ind., said he expects to lose 250 of the harbor's 925 boat slips this year, a potential loss of $525,000 when associated services are taken into account. The city, which hosts a major regatta for deep-draft sailboats each June, is having the Corps of Engineers dredge the outer harbor, where water depths have dropped to as low as four feet in places. Scott Stevenson, harbor manager for the Chicago Park District, which manages marinas berthing 5,000 boats, said that some boat ramps will have to be extended and that the channel leading to one harbor will have to be dredged about three feet deeper because of the lowered water level. In northern Michigan, two ferry services that operate between Cheboygan and Bois Blanc Island in Lake Huron have been forced to shut down because the water depth in the island's harbor entrance is less than four feet. Pleasure boaters throughout the Great Lakes have seen their launching ramps, docks and piers rendered useless by the receding waters and are clamoring for permits that will allow them to deepen their harbors and get sailing or motoring again. Last year, applications for dredging in the middle Great Lakes increased by 30 percent. So far this year they have increased by nearly 40 percent over the same period last year, said Robert Deroche, project manager at the Corps of Engineers' Detroit District headquarters. Last year, there were more than 1,000 dredging projects along Michigan's coastlines alone, more than twice the number in the previous year.
