Lake Superior’s water level declined three inches last month and is predicted to decline another inch in November. Superior is now 13 inches below its long term average for this time of year, and 8 inches lower than a year ago.
Lakes Michigan-Huron, St. Clair, and Erie are also below last year's levels. These lakes are down 7 to 9 inches and are predicted to further decline over the next month from between 1 to 4 inches.
Water levels in the Great Lakes typically fluctuate according to the season, rising in the spring and falling over the winter, however, current water levels seem to be trending downward as climate change causes air and water temperatures to rise, and ice cover in winter to decline.
According to the U.S. Army Corps of Engineers (USACE), most predictions indicate that climate change could cause prolonged declines in average water levels into the future. These declines could create large-scale economic concern for virtually every user group in the Great Lakes basin. Dramatic declines could also compromise the ecological health of the Great Lakes, particularly in the highly productive nearshore areas.
The Great Lakes cover more than 94,000 square miles and hold an estimated 6 quadrillion gallons of water. More than one tenth of the population of the United States and one-quarter of the population of Canada inhabit the Great Lakes watershed.