I noticed that you were a little farther than the boat ramp in that picture. If you use a floatie or strike indicator just above the hook and below the sinker it will hold your bait up out of the muck on bottom.
I have never tried using bait fishing below the dam for trout. I always use a 3" plastic worm and 1/16th or 1/8th oz jighead. That is all I have ever really used.