Water levels continue to drop, and will keep falling for another week or two as 'they' draw down the levels.  Fishing has been somewhat more challenging in that the water clarity has improved dramatically and lighter tippets are required.  Small dries hatching during overcast times- blue winged olives, as well as the terrestrials- hoppers, ants, beetles- during midday into the afternoon.  Still seeing some evening caddis and the big October Caddis pupae are on the radar.  Fish are increasingly consentrated in the larger water as it becomes more scarce....lighten your tippet in slow times to 6x or so, particularly if you're targeting fish feeding on little baetis (BWO's).  Hoppers etc are still a great bet, and the lower canyon is officially wadeable from here on out.  This is the best time to fish the Yakima, as access is great, flows are predictable, some cooler weather is changing the food supply, and the fish are hungry and competetive.   Fish the october caddis pupa during off-hatch times or when your hopper rig isn't producing.  Maybe drop a little #18-20 attractor nymph off the bigger fly.  Indicators help.