The water disappeared twice, coming back each time as we rounded a canyon corner. My theory is that it was related to the rock layers. At one section the canyon got very narrow, and consisted of hard metamorphic rock. My guess is that water percolated through the sand above until it hit this resistant layer, then bubbled to the surface.
All too soon, we lost the water for good, and the rest of the canyon traverse was across the sandy wash.
Outside the canyon, we joined up with a marked trail again, and followed it through the desert, and up a ridge into juniper-pinyon forest before coming out at our car. Along the way Kevin was startled by a Horned Toad shaking off the sand from its body and running off the trail (my picture is the same as Kevin’s, so not shown here). We made it to the car at 11:45– plenty of time to pick up the other car, enjoy a wonderful shower, and catch our plane back to Colorado.