Water levels for all of the Great Lakes remained higher than normal in August and still above last August’s levels by 3 to 23 inches, according to the Detroit office of the U.S. Army Corps of Engineers.
Higher water levels are expected through fall and into December on lakes Superior, Michigan-Huron, St. Clair and Erie, the Army Corps of Engineers showed.
Lake Ontario set a new high in May at 248.69 feet above sea level and is expected to remain higher than average though November, but is expected to return to average levels in December, according to figures the Corps released last week.
Data show precipitation during the month of August was near average for the Great Lakes basin. Lake Superior received 20 percent more rain and Lake Michigan-Huron received 10 percent more than average. Lakes Erie and Ontario received 71 percent and 86 percent of average precipitation, respectively, in August.
From July to August, Lake Superior rose just more than 1 inch and Lake Michigan-Huron rose less than half an inch. Lakes Erie and Ontario declined 4 inches and 10 inches, respectively.
The net basin supplies were above average for Lake Superior and Lake Erie, near average for Lake Ontario and below average for Lake Michigan-Huron.
A wet spring season had experts predicting summer water levels for the Great Lakes would be higher than normal and above last year’s mark.
April and May were wetter months than average across the Great Lakes basin, with lakes Ontario and Erie getting more rain than the other lakes, said Keith Kompoltowicz, chief of watershed hydrology at the Corps’ Detroit District. It was enough to force the agency “to adjust our forecast for the summer up a little bit,” he said in June.
“It’s all a result of weather patterns and the fact that in southern lakes like Lake Erie and Lake Ontario, they bore the brunt of what Mother Nature provided in terms of rainfall,” Kompoltowicz said.
Boaters and others have welcomed the rebound in lake levels that are closer to their historical averages during the past three years. They allow commercial vessels to carry more cargo, recreational boats to get in and out of marinas and harbors more easily, and property owners to enjoy more traditional shorelines.
Five years ago, lower-than-normal lake levels had boaters concerned about getting the pleasure crafts out of harbor, much less into the lakes. The crisis atmosphere helped trigger a state-sponsored $21 million emergency dredging program for 58 harbors in Michigan.
But the rising water levels have brought other benefits, including a tendency to help in stopping the development of algae in shallow areas, which have created toxic blooms. The downside to rebounding lake levels is they can eat into shorelines for some homeowners.