RiverLiver
I though that you would like to know a little bit more about Mayfield Dam, and why the flows are so dirty. The reason for the "dirty" water is not because; Mayfield releases water from the "bottom". Mayfield dam has very shallow intakes for its turbines. The maximum operating range is from 425 feet to 415 feet. The minimum operation elevation is 415 feet.
The intakes on Mayfield are extremely shallow and that's why the elevations at Mayfield never drop below about 15 feet. The "dirty" water usually comes from the high flow events of the Tilton River. During the 20,200 cfs flows of our last high water even, over 12,000 cfs was coming directly from the Tilton River. When flows get over 8,000 cfs, you can expect to see Mayfield reservoir become dirty within 4 days of such a flow event. There is literally "no area" for the silt from the Tilton to settle out before it reaches the intakes at Mayfield.
Now Mossyrock dam is total different story! The intakes at Mossyrock vary from 248 feet to 285 feet. That's why Mossyrock Dam fluctuates so much during the summer when Mayfield stays almost the same height. When Mossyrock gets dirty, we're in for a long period of "dirty water". I Hope that this will give you a better understand of "why" the Cowlitz gets dirty.
Remember, when flows reach over 8,000 cfs on the Tilton, the Cowlitz will mosy likely be "out" 4-5 days later
Good luck and good fishing!
Cowlitzfisherman
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Cowlitzfisherman
Is the taste of the bait worth the sting of the hook????