Del Striegel and I were fishing up the Middle Prong last year and had a pretty good sized and extremely upset timber rattler come washing down the stream between us. It was in fast water and was not happy about it, he would try to get up on a rock as he went tumbling past ( one of which Del was standing on!) He ended up about twenty feet below us in flat water and swam to shore. A park ranger told us that the snake was probably shedding and either fell into our simply got washed into the faster water. I have had a few water snake encounters before, but now I tend to pay a bit more attention after seeing a rattler that close. Be careful and don't forget to have fun.