My sister lives in Iowa and knows the people involved in this accident, which proved fatal to one of the paddlers. They were all skilled sea kayakers wearing Gore-Tex drysuits, PFDs, etc. Here is the link to the report in American Whitewater: https://www.americanwhitewater.org/content/Accident/detail/accidentid/44238/ Fortunately, those of us in the PNW don't have to play around behind low head dams to find challenging water and current, but please be very, very cautious if you are ever on a river and see a perfect river-wide horizon line. The hydraulics behind a low head dam (even a small one) make them extremely dangerous. I doubt that even a Class V whitewater paddler in a creek boat could survived/escaped this particular situation. Low head dams kill multiple paddlers every year. Be safe out there!