The Great Lakes Basin… Fresh Water In Danger
Facts and Figures about the Great Lakes
Shared with Canada and spanning more than 750 miles (1,200 kilometers) from west to east, these vast inland freshwater seas provide water for consumption, transportation, power, recreation and a host of other uses.
The Great Lakes are one of the world’s largest surface freshwater ecosystems.
- 84% of North America’s surface fresh water
- about 21% of the world’s supply of surface fresh water
- Physical Features of the Great Lakes
- The Great Lakes Atlas Third Edition 1995 is available from NSCEP, US EPA’s publication service
- Data and Map Floor Studies of the Great Lakes from NOAA’s Great Lakes Environmental Research Laboratory
The Great Lakes Basin
The Great Lakes basin encompasses large parts of two nations, the United States and Canada.
- Nearly 25% of Canadian agricultural production and 7% of American farm production
- Population is more than 30 million people – roughly 10% of the U.S. population and more than 30% of the Canadian population
The Great Lakes basin is defined by science, engineering and politics.
Most of the basin is defined by hydrology; watersheds that drain into the Great Lakes and their connecting channels are in the Great Lakes basin.
A combination of engineering and politics (Canadian) have resulted in the Rideau exception being included in the Great Lakes basin (the orange striped polygon on the Canadian side of the St. Lawrence River). The Clean Water Act defines the orange striped polygon on the US side as part of the Great Lakes basin (though hydrologically it drains into the St. Lawrence River).
The boundaries on these two maps are defined by 8-digit Hydrologic Unit Codes (HUC8). These may change slightly as more detailed mapping is completed for these watersheds. The maps also display the counties in the Great Lakes basin.
The overall condition of the Great Lakes has been assessed as “fair and unchanging” in the 2019 State of the Great Lakes joint report by the U.S. Environmental Protection Agency and Environmental and Climate Change Canada, published on June 3
The Great Lakes are stressed. Climate change is making it worse. The Great Lakes are struggling under the combined weight of many ailments, from invasive species and toxic chemicals to the nutrient runoffs that fuel Lake Erie’s chronic algae problem. And in many cases, climate change is making it worse.
Of all of the Great Lakes, Lake Erie had become predominantly polluted by the 1960s, largely due to the heavy industrial presence along its shores. With 11.6 million people living in its basin, and with big cities and sprawling farmland dominating its watershed, Lake Erie is severely impacted by human activities.
Lake Superior has always held the record as the clearest, most pristine lake of all five Great Lakes.” For the study, scientists analyzed satellite images captured
Of all of the Great Lakes, Lake Erie had become predominantly polluted by the 1960s, largely due to the heavy industrial presence along its shores. With 11.6 million people living in its basin, and with big cities and sprawling farmland dominating its watershed, Lake Erie is severely impacted by human activities
**Dan Egan is the author of “The Death and Life of the Great Lakes” and journalist in residence at the Center for Water Policy at the University of Wisconsin-Milwaukee’s School of Freshwater Sciences.
He lives on the shores of Lake Michigan, in Whitefish Bay, WI with his wife and four daughters … the one Great Lake is right in own backyard.
His words and research led to the creation of The Death and Life of the Great Lakes…and his contribution to the July special feature in the New York Times