Smooth granite rose in graceful arcs over the San Joaquin River, pinching a tumult of whitewater between vertical walls deep in the backcountry of California’s High Sierra. From a clinging perch just upstream, three kayakers gazed beyond the gauntlet to a calm pool in the distance. If they could just get there, the canyon would open, and they would be free. But there was no avoiding the boulder-strewn mess at their feet. Even with the climbing rope and pitons they carried, a portage was not an option here. It was time to send in the probe.
The “probe” in this case was Reg Lake.