MSN2Travelers, I'm a bit confused about your comments and your summary. The report I cite -- the one you say is "very old and contains data that is no longer valid" -- is the exact same one you cite. You do realize the link I posted was the first report from this study, and you simply posted the first and then final reports. The final report specifically states:
"In its first report to the IJC, Impacts on Upper Great Lakes Water Levels: St. Clair River, the Study Board identified a number of specific “legacy” recommendations regarding strengthening data collection, scientific knowledge and institutional capacity. In this final report, the Study Board reaffirms those recommendations..."
In addition, your summary seems to misrepresents the report(s) you are citing. Perhaps you are more intimately connected with the IJC process, so are drawing on different sources for your final comments. If so, I'd value seeing the references. This is a complicated subject (a point the report that you and I referenced keeps making). This research is not the final piece of the puzzle. That said, this IJC report seems to be the most definitive and complete piece of work to date.
It concludes, amongst other things, that "Restoration structures designed to raise Lake Michigan- Huron water levels would result in adverse effects on certain key interests served by the upper Great Lakes system."
IOW some interests would suffer while some would benefit. Specifically, as you quote, "Commercial navigation and recreational boating and tourism interests would benefit, while coastal zone interests, hydroelectric generation and indigenous peoples would be adversely affected.
So, the actual conclusion they reach is that while it is possible to engineer a solution that would raise Michigan and Huron, it is unclear whether this would be a good idea. There would be winners, and there would be losers.
I agree with you that the upper lakes are at a historic low, and appear to be into a period that is unprecedented. I don't agree (and the research you and I both cite) that the principal cause of this is the St. Clair engineering, although it is has contributed to the problem.
The major contributor to lower lake levels appears to be increased winter evaporation due to decreased ice coverage. A second contributor (at least for Lake Superior) appears to be reduced precipitation levels. The real solution is to address the causes of climate change, but that is hard, and requires that we all do something (not just "government"). And none of this is going to help marinas in Milwaukee.