Back in my early days of flyfishing and living in West Yellowstone, MT, I was fishing the Box Canyon stretch of the Henry's Fork with Bob Jacklin and friends and, after stepping into the river and fishing for about fifteen minutes from the middle of the river, I cast back towards the bank, about right where I stepped into the river, and hooked the largest trout of my life!
Goes to show that no matter the size of the water the fish may be right under your feet, so wade with care, or not at all if possible.

Kelly.