The Great Lake elevation variations are meteorological, not tides- gravity of the Sun and Moon account for about 5 centimeters of difference, according to the link. The runoff from storms and storm water sewers runs into the lake because it's naturally lower than the surrounding land mass but also, there's a subcontinental divide not far to the West. The last few years, we have had lots of rain, but not as much ice- the ice alone would have prevented the damage because it would have prevented the waves reaching shore. Lake Michigan's area is more than 22K square miles- according to Wiki, the elevation rose about six feet in 6.5 years after 2013. The whole Great Lakes system needs to be considered, too- all rivers near the lakes lead to them, but there are few major outlets for Lake Michigan; the main ones at the South being the Chicago and Calumet Rivers.
I mentioned some friends whose boat stayed at the damaged yacht club- we took their most recent boat to Sturgeon Bay, WI two years ago and on the way up, it was fairly calm. While we were there, a storm rolled through from the Northeast and it really riled the water. Before we left a few days later, it was choppy on the bay side of the lake, but when we reached the lake, it was rough. We headed back on a Monday and had 4'-6' chop which wasn't too bad, as long as our speed wasn't excessive but it became rougher as the day went on. We stopped for lunch and it was worse and we stopped for dinner in Two Rivers, which isn't terribly far from the previous harbor but it's not protected from the waves. We decided that staying there would make sleep very difficult and the concrete dock would probably beat the crap out of the boat, even though we had tied it with at least 6 lines and placed fenders along the hull. It was dark when we left for Manitowoc and when we reached the lake, we found 6'-9' chop, coming from two directions- good thing we had autopilot because that would have been too much like the three hour tour from Gilligan's Island. It took over an hour to go six miles. I wouldn't have gone along if they still owned their last boat- the one they have now is 38 feet and weighs more than 20,000 lb, so it really wasn't terrible. Dicey, but not frightening. We looked out on the next day and stayed put because the waves had increased to 9'-12'.
For contrast, the two photos show the same white lighthouse at different times- the top is from before the sign went up and all are from inside of the wall, at different angles. They could use the interior of this place for a Steven King movie.
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Here it is with rough water-
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Water levels in the Great Lakes change because of weather effects, not tides.
oceanservice.noaa.gov
