A few years ago, I saw a boat full of mexican, laotians, something not american, they were yelling and were not speaking english. they were catching catfish every time they dropped a line. It was below Old Hickory dam. One generator going and moving a lot of water. Every so often there would be an increase in flow and the water would rise a couple feet. I knew the water was rising and falling because they had their boat tied to either side of the generator hole NEXT to the generator that was running. Their boat would literally rock and raise up a few feet and stay up til the increase in flow went away, only for it to happen again at about the same time frame. I was waiting to see if I was going to have to try rescue them. They were still there tied up and fishing when I left.