Great Lakes Water Levels – Waterspouts and Great Lakes News

Bill's Blog

The top pic. is from our Noto’s a the Bil-Mar camera at Grand Haven. The ship is the Calumet. It made the trip up from Indiana Harbor Sunday PM and pulled into the Grand Haven Channel shortly after sunset. You can follow ships on the Great Lakes (and around the world) at

The water level of Lake Superior fell one inch in the last month. Rainfall in July was variable. Marquette had 1.8″ of rain, while S. Ste. Marie had a whopping 6.47″. However the rain that falls in SSM quickly gets down into Lake Huron down the St. Marys River. Duluth MN had 2.75″ of rain. They only had one day with measurable rain from July 1-July 22. It’s also been dry across the Dakotas into Montana.

Lake Superior is down 9″ in the past year. That’s a substantial drop. Each inch of water on Lake Superior represents 550 billion gallons of water. So, 9″ would be a loss of 4.95 trillion gallons. I’m told the average person uses 25 gallons of water to take a shower. If there’s 330 million people in the U.S. – see if you can figure out how many showers the people of the U.S. could take with that loss of water from Lake Superior.

Lake Superior is now just 2″ higher than the average late July level and 12″ below the highest July level reached in 2019.

Lake Michigan/Huron (one lake for lake-level purposes). is up 2″ in the past month, but down 17″ in the past year (again, that’s a lot). The severe storms of last Wednesday night produced a seiche (meteotsunami) on the southern part of Lake Michigan. The water level rose and fell up to 2.5 feet as the northwest wind pushed the water down to the southeast end of the the lake. That would have been more of a problem if the lake level was a foot and a half higher.

Lake Erie is up 5″ in the past month, but down 6″ year-to-year. The lake is still 20″ higher than the July average, but it’s 11″ lower than the July record level set in 2019.

Lake Ontario is up 6″ in the last month. The lake is down 10″ in the last year and is 6″ BELOW the July average. The lake is 37″ lower than the record high July water level of 2019.

Lake St. Clair is unchanged in the last month, but down 11″ in the last year. The lake is still 20″ above the July average level, but 12″ below the highest July level reached in 2019.

OK – time for me to get some sleep – I’ll have to finish this thread later today – thanks for reading my blog.

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