The river was relatively calm in this stretch, except for some squirrelly hydraulics. Jerry was thirty-nine years old, and he knew how to swim. With that much loose, shifting weight in the boat, the margin for error declines significantly. A basic course likely would have given them the skills to handle the converging currents and would have taught them not to overload the canoe. The convergence of two currents on a river typically produces disruptions in the flow that, if not anticipated, can capsize a canoe.
Boaters have to constantly look ahead and anticipate hazards.
See Chapter Three, Navigation. In this case, the lack of a PFD was literally the difference between life and death. She was lucky. The Big Hole is a popular fishing river, especially in June during the runoff, and many anglers use drift boats with anchors. The anchor rope had a knot in the end so the operator was unable to completely release the anchor when it snagged bottom.