Two of us floated the Yakima in one person pontoon boats from Swauk Creek to Thorp. It's only 5 miles but we took 7 hours (10 to 5) due to the low flow. My buddy had consistent success (20+ fish all under 12 inches)using a soft hackle nymph. I fished mostly small dries (#16 & #18) and got fewer takers but 3 were around 18". Water was really low and clear, but in the high 50's. The air was in the 80's. Not too many people on the river.