I am in upstate NY ... all of the leaves are down and water is 54 degrees and crystal clear.
My neighbor doesn't cover his .... he just waits until now and gets it clean and winterizes it and then scoops the occasional leaf etc out over the rest of the fall and winter.
I have a plastic tarp and water bags so i don't see it as any safer.
It sure would be nice to not have to fill and empty all of those water bags.
Sooo ... why would i need to put the plastic cover on??