Well, obviously not enough to walk on, most of it looks pretty solid but probably a crust, I think you would quickly die if you tried walking it ,, Doesn't happen every year, occasionally it freezes solid, sometimes not at all and everywhere in between.
Canada on the other side, Ambassador Bridge can be seen in the distance in the 2nd shot.

Canada on the other side, Ambassador Bridge can be seen in the distance in the 2nd shot.

