Upper Willamette River System Fishing Report and Forecast Posted on August 18, 2022August 18, 2022 by Glenn Zinkus McKenzie River Trout. Green Peter TroutGreen Peter Trout and Kokes. Detroit Lake Producing Kokes. Middle Fork Willamette Trout and Steelhead. and Kokes. Alton Baker Canal: Alton Baker Canal was stocked with 900 legal size trout. ... This post is only available to Members. If you are a Member, please be sure to log in and remember to select the Remember Me option. If you want to become a member or find out more, take a look here. If you are looking for our free content head here. And, if you need a hand, please reach out here.