Potters Creek boat launch #21 had a fishing dock but don't know if it's still there after the flood.
Don't take this wrong, but but when I was 16 years old I walked miles of river bank looking for good places to fish.
I would check the areas around some of the launches for likely looking areas. Don't fish off the launches because you'll get ticketed, but towards the backs of the coves where you can get access from a boat launch.
Also some of the parks have miles of shoreline.
Finding heavily beaten paths along the shorelines and looking for beer cans and worm boxes, disgarded lure packages also tip you off to what may be a favorite spot.
Canyons shoreline is mostly rock, with steep dropoffs, but if you can find some sand or gravel with a gentle slope to deeper water with some hardwood, it's money.
Here is a hint....Boat ramp #17 off to the right of the ramp.