Upper Willamette Fishing Report and Forecast Posted on September 30, 2021September 30, 2021 by Glenn Zinkus Detroit Reservoir and McKenzie River Trout. Lower Willamette River: Coho are starting to ascend Willamette Falls in good number. Check the fish passage numbers HERE. Coho passage in recent days has been excellent at Willamette... 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.