Update on Lake Inferior
John coined that name for the former Lake Superior in his earlier post on its falling water levels; now the New York Times tells us why. It appears that it may not be climate change or declining snow melt in Canada, but the Army Corps of Engineers, renowned also for their levee design and maintenance in New Orleans. Starting in the mid sixties, they dredged and widened the St. Clair river between Lake Huron and Lake Erie. The Times says: The flow may be eroding the riverbed. The erosion may in turn result in increased outflow, more than can be replenished by rain or snowmelt, according to a study by a group of Canadian coastal engineers. If the new estimates are correct, 2.5 billion gallons a year are being lost through the expanded parts of the St. Clair, roughly the equivalent of the amount diverted annually for Chicago’s needs.
Long term trends indicate Lake Erie rising while the upper lakes are falling, which would seem a likely result if the flow is increased. ::New York Times