Great Lakes Great Lakes The Great Lakes (), also called the Laurentian Great Lakes and the Great Lakes of North America, are a series of interconnected freshwater lakes located primarily in the upper mid-east region of North America, on the Canada–United States border, which connect to the Atlantic Ocean through the Saint Lawrence River. They consist of Lakes Superior, Michigan, Huron, Erie, and Ontario, although hydrologically, there are four lakes, Superior, Erie, Ontario, and Michigan-Huron. The lakes are interconnected by the Great Lakes Waterway. The Great Lakes are the largest group of freshwater lakes on Earth by total area, and second largest
Great Lakes "Since the early 1970s, the level of treatment to reduce pollution from waste water discharges to the Great Lakes has improved considerably. This is a result of significant expenditures to date on both infrastructure and technology, and robust regulatory systems that have proven to be, on the whole, quite effective." The commission reported that all urban sewage treatment systems on the U.S. side of the lakes had implemented secondary treatment, as had all on the Canadian side except for five small systems. However contrary to federal laws in both countries, those treatment system upgrades have not yet eliminated Combined sewer