Report: Lake levels to drop
By Gitte Laasby
Published November 28, 2007
By 2050, spring temperatures in the Great Lakes region could increase by as much as 9 degrees Fahrenheit and summer temps by 7.2 degrees. And lake levels may drop by as much as 4.5 feet as a result of less precipitation and more evaporation.
Those are just some of the effects scientists expect climate change to have on Great Lakes states, according to "Climate Change and Great Lakes Water Resources," a report that synthesizes the latest research.
Climate change also could reduce groundwater levels and impact fishing, wildlife, wetlands, shoreline habitat, tourism and shipping, the report said.
Climate change packs one-two punch on Lakes
The Great Lakes are the drinking water source for more than 40 million people and make up nearly a fifth of the world's freshwater, but only 1 percent of it is renewed every year through precipitation.
That concerns scientists behind a new report: "Climate Change and Great Lakes Water Resources." The report predicts lake levels may drop by as much as 4.5 feet by 2050 as a result of less precipitation and more evaporation.
As groundwater is reduced, there will be increased demand to divert water from the Great Lakes to other areas of the country, for instance the South and Southwest.
"Agriculture, manufacturing and power generation will need more water and put more pressure on water withdrawal from the Great Lakes," said Noah Hall, environmental law professor at Wayne State University in Detroit, who co-authored the report released Tuesday by the National Wildlife Federation.
Climate change is mainly caused by emissions of greenhouse gases, such as carbon dioxide. Managing emissions, doing a better job of water conservation and enacting the Great Lakes Compact to prevent out-of-basin diversions are keys to preventing the worst effects of climate change, said Molly Flanagan, water program manager with the National Wildlife Federation.
"If we had to, we could find a way to live without oil. None of us could live without water," Flanagan said. "Praying for rain is not the best way to manage our water resources."
Gary environmental activist Lee Botts said decreasing water levels have been a concern for years.
"A lot of the new information is confirming what was suspected back in 1988," Botts said.
Did you know?
The city of Chicago diverts more than 2 billion gallons of water every day from Lake Michigan. After the water's been used and treated, the majority goes into the Chicago Sanitary Ship Canal, from which it flows to the Des Plaines River to the Illinois River and ends up in the Mississippi River.
"I anticipate it would impact water levels (in Lake Michigan), by 3 to 4 inches," said Noah Hall, an environmental law professor with Wayne State University Law School in Detroit. But "to a large extent, the reduction in lake levels from the Chicago diversion has been offset by two large diversions into the Great Lakes."
The diversions into the Great Lakes occurred around World War II and were done to generate power, Hall said.
Sewers in Chicago can overflow into Lake Michigan on rainy days with high water levels or when the wind is in the right direction, said Allen Melcer, deputy chief of the water quality branch of the Environmental Protection Agency, Region 5.