A comment above mentions a demilitarization treaty of the Great Lakes.

I am definitely not suggesting it's a foreign state. That's less probable than unknown domestic military activities.

Reports of odd lights in sky or water. Or general nonspecific stories of "weird shit".

There's more too, but those are fish stories (sharks, people claim).

I like to do outdoorsy stuff, so this is what I've heard from fisherman, ferrymen, etc.