Rick Sanders, 52, drowned on California's West Walker River during an exploratory run of an upper section. His group intended to do the lower section, and after finding it too high they elected to scout an unexplored upper section near Sonora Pass. After running a section of fast Class III Sanders, an expert kayaker, missed an eddy an was swept into an overhanging tree. He flipped to miss the tree, but had difficulty rolling up. He was swept downstream into a 'Class V-VI Gorge" and the group lost sight of him. He was found out of his boat pinned against anotherr tree. It took the combined efforts of several rescue squads to free his body
This exploratory took a turn for the worst when it started changing character and the victim was unable to stop. The challenge in these pioneering runs is to maintain control and avoid getting "sucked into" rapids that are too difficult. This task gets more difficult as the water rises.