We had a similar issue on a lake by St. Cloud years ago. So the local Sportsman’s club I was apart of placed garbage cans at a couple lakes and had members empty them once a week. The DNR told us to remove them immediately because they pay someone to clean the public accesses.
I would contact the DNR and tell them to get out there and clean it up. After all “they pay people to clean the accesses”. Seems ridiculous a private party isn’t allowed to help keep a public area clean…
My kids an I pick up garbage every time we see it, I just hope we don’t get in trouble