We've got 70,000 cfs moving down-river right now. I decided to run over to the Pedestrian Bridge / Zink Dam area and get some video. This is a good example of the "Washing Machine Effect" at the foot of a low-head dam. There is a good reason why these things are called "drowning machines".
If you're near one in a boat, STAY AWAY! If you're near one on a smaller stream, stay safe! I would only go near one if I knew there was little or no water moving over it.