The McKenzie and Willamette Rivers have settled into summer low water stages and mid day fishing has slowed a bit. Fishing has remained solid morning and evening with a variety of bugs and tactics. As the sun moves directly over the river fish go deeper and Euro Nymphing tactics have been best.
Water temps are still cool and one can still find fish on the surface early and late. Best dry fly patterns for the McKenzie and Willamette include Tan Caddis #14 and #16, Parachute Purple Rooster #14 and 16, Parachute Adams in #14 and #16, Little Yellow Stone Fly Patterns in #16, Elk Hair Caddis Yellow in #16. For mid day tactics use a smaller Chubby #10, with a smaller dropper nymph #14 as your searching tactic. Focus on drop offs and fast oxygenated water.
For Euro tactics look for “deeeeep water” with a fast walking speed and bedrock slots that offer fish protection from sun and birds. Make sure you are using 5x tippet to your last fly. Keeping everything from your sighter tippet down in the 4x and 5x range will facilitate sink rate and stealth. Try Jigged 20 Inchers, and slender jigged flies like Loren’s Stud, Hindmarsh’s Pleaboi and Dally’s Tailwater Jig.
At only 480 CFS most of the boat traffic is off of the Middle Fork of the Willamette between Hills Creek Dam and Lookout Point Reservoir. Wading access is way easier at this flow and anglers can even cross the river in places. Fishing above Hills Creek is also worth a look. Similar patterns as the McKenzie are working well on the Middle Fork.