For wade fishing at the falls, I don't go until it is under 14 and that would be high for me. I like to flyfish for bass during the summer primarily, so by then the flows are usually pretty consistant. I have now twice been caught away from the bank when they decide to bring the flows up, it is a scary, bumpy, wet ride. Of all of the places I have fished from coast to coast the falls is one of the most difficult places to wade on the rocks, they are slippery, sharp, and did I say slippery.