How do you design a wooden dory strong enough to handle Grand Canyon whitewater? If you're Zarn, you start by spending as much time on the river as humanly possible. Today’s Colorado River dories are descendants of McKenzie River drift boats designed to run the McKenzie River in Oregon. She started asking around, and soon stumbled across Brad Dimock, a master boatbuilder and owner of Fretwater Boatworks, a Flagstaff outfit that specializes in wooden boats. Zarn isn’t surprised; it had always felt like a matter of time before other people started waking up to the magic of wooden boats.