The three of us where in the water for at least a hour. I didn't have any issues and the others did not report on anything out of the ordinary. I have heard of the mites being there though. Maybe certain weather conditions influence their activity.Looks like an awesome trip. Did the red spider mites bite everyone's skin right at the water level. We were there 10 days after you on a moto trip had a good soak, got quite a few bites, but worth it.
You could have told me you were in Chile with some of these pics. No idea Oregon had spots like this. Thanks for the pics and trip report.