All five Great Lakes are now at all-time record high June water levels. Above average rainfall, high flow on area rivers and low evaporation continue to cause water levels to surge.
The water level of Lake Superior is up 2″ in the last month, up 10″ in the last year (that’s a gain of 5.5 TRILLION gallons of water) and is now 16″ above the average June water level. The lake is now 4″ higher than it has ever been in June
The water level of Lake Michigan/Huron is 6″ higher than one month ago, 15″ higher than one year ago and 32″ higher than the June average level. The lake (one big lake for lake level purposes) is now 1″ higher than it has ever been in June.
The water level of Lake Erie is at an all-time high – it has never been higher. It’s up 4″ in the last month, up 10″ in the last year and is now 32″ higher than the June average. It is also 5″ higher than the previous June record.
Lake Ontario is also at the highest level it has ever been at, up 4″ in the last month, up a whopping 28″ year-to-year and it’s now 33″ above the June average level. It’s 3″ higher than the previous June record.
Lake St. Clair is also at an all-time record level. It’s up 6″ in the last month, up 11″ in the last year and is also 33″ higher than the June record level. It’s 4″ higher than it has ever been.
This map shows rainfall departure from average over the last 30 days (as of 6/20). Note the large area of the Southern Great Lakes that has had more than 4″ above average rainfall.
All the rivers that connect the Great Lakes have well above average flow. The flow on the St. Clair River (between Lake Huron and Lake St. Clair) is at 254,000 cubic feet per second, compared to an average flow of 194,000 cfs.
Here’s some river flow data from the Great Lakes basin Friday PM: Grand River at Grand Rapids – 10,100 cfs (average 2,570 cfs), Saginaw River at Saginaw – 16,200 cfs (average 2,660 cfs), Fox River at Green Bay WI – 10,300 cfs (average is 6,410 cfs) and the Maumee River near Defiance OH – 25,300 cfs (average is 1,440 cfs). As you can see river levels are very high and this will cause water levels to continue to increase.
Grand Rapids MI recorded just 15 dry days in the 51 days from May 1 to June 20. The percent of sunshine for G.R. for the 12 days ending June 20 was just 25%, compared to an average of 63%. This is the 12th consecutive month with above average cloud cover. Every single month has been cooler than average so far this year in G.R. We’ve also had well above-average ice cover in four of the last six winters. This means lower evaporation rates and hence, higher water levels.
Among the concerns – lakeshore flooding, lakeshore erosion, waves crashing over the piers and breakwaters, submerged objects posing a danger to boaters, very slippery spots on piers and breakwaters where high water has promoted the growth of algae and electric shock as water climbs over electric lines on piers and breakwaters. Also, the high water means much less beach to lie on at lakeshore parks.