Great Lakes Water Levels


I took this pic. a couple weeks ago. This is the boat launch into the Boardman River in downtown Traverse City MI. You can see how high the water level is here. Here’s the latest Great Lakes water levels as of Fri. AM 8/2.

Lake Superior Water Level Graph

Lake Superior is up 1″ in the last month, up 9″ year-to-year (a big increase) and is now 13″ above the August average level. The lake is now 1″ higher than the previous August record high level set in 1952. Since Jan. 1, Marquette’s total precipitation is 6.72″ above average and S. Ste. Marie is 8.85″ higher than average.

Lake Michigan/Huron Water Level Graph

Lake Michigan/Huron is down 1″ in the last month, but up 15″ in the last year. Again, that is a very large yearly increase. Each inch of water on Lake Michigan represents 390 billion gallons. So, 15″ is an increase of 5.85 trillion gallons. Lake Michigan/Huron is 2″ below the August record high level set in 1986.

Lake Erie Water Level Graph

Lake Erie is down 3″ in the last month, but up 14″ in the last year. Lake Erie is 33″ above the August average level and that’s 6″ higher than the previous August record high level set in 1986. Since Jan. 1 – Cleveland is now 5.45″ of precipitation higher than average since June 1 and Toledo is 6.47″ above average precipitation since the start of the year.

Lake Ontario Water Level Graph

Lake Ontario is down 7″ in the last month…but the level is up 29″ in the last month (!). It’s 33″ above the average August level and it’s now 5″ higher than the previous August record high level set in 1947.

Lake St. Clair Water Level Graph

Lake St. Clair is unchanged in the last month, up 14″ in the last year and is now 34″ above the average August level. It’s 5″ above the previous August record high level.

The flow on the rivers that connect the Great Lakes is well above average and that will continue well into next year. The St. Clair River at Port Huron has a flow of 271,000 cubic feet per second, compared to an average flow of 191,000 cfs.

The high water level means it’s much easier for waves to wash over the piers and breakwaters – and a bigger wave can knock you off the breakwater into the lake. There’s also a concern that fall storm systems will cause lakeshore flooding and significant erosion.

Lake Macatawa – Early Fri. PM

The high water level affects all the lakes that connect to the Great Lakes (Lake Macatawa, Muskegon Lake, etc.).

River levels have been declining, but are still at higher than average flow: The Grand River at Eastmanville has a flow (Fri. noon) of 2,240 cfs compared to an average flow of 2,010 cfs. The Muskegon River at Croton has a flow of 1,310 cfs. Average flow is 1,140 cfs. The St. Joseph River at Niles is at 3,020 cfs – average is 2,070 cfs. The Saginaw River at Saginaw is now at 2,230 cfs – average is 1,680 cfs…and the Fox River at Green Bay WI is at 3,260 cfs compared to an average flow of 1,680 cfs.

Great Lakes water levels usually decline in the late summer and fall. We are in a drier than average weather pattern right now.

Great Lakes News: Rising waters special report. Rising waters affecting Great Lakes beaches. Asian carp taking over Kentucky Lake. Norton Shores home clings to top of eroding dune. High water level causing problems at Holland St. Park.

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