Rick, what season are you talking about?
Let's talk winter for now. Let me just put out some basics about rivers that would apply there.
Shallow rivers have about the same temperature from surface to bottom, all cold in winter, all warm in summer.The slower the river the warmer, absorbing sunlight heat, allowing bass to hang around a little shallower. Exception: new water coming down from a slow rain over a warmed watershed. I'll talk about backwaters and bayous later.
There might be a cold water spring pumping out 50 degree water in August, but water from upstream catches and mixes it until that has no effect on the river. Bass might hang around a cold spring a while, but the water from springs is usually devoid of O2. So the bass must contend with and be satisfied with all places in the river, not finding comfort most of the year, being cold-blooded and dependent on external temperature for activity. Another exception is, in winter bass totally shun current, while in warm weather they will side up next to current because current brings them their forage. It would be a little warmer in the current with the shoreline frozen, but requires burning too many fat calories to deal with the current pressure. If they can find a patch of dark mud in 12" of water on a sunny day they'll probably go there for the day if it's out of the current, but that's the first water to freeze at night and under day clouds. The deepest water won't freeze, but only because of water flow and kinetic/friction energy keeping it flowing to keep it a little above freezing in a really hard winter.
Where am I with this :-\ I got a little lost...maybe ya'll did too?
The pike and numerous other fish can tolerate cold shallow water longer so tend to claim those areas in winter, finding shore minnows and other critters to eat that never go deep. BUT, they keep claiming shallow weedy places all year. What ya gonna do? In general, in winter it's best to avoid shallow even if you find some a degree or two warmer than the river. Let the pike have it.
As the water gets colder bass prefer to go deeper and suspend over solid rock, or at least rock rubble over rock. They "know" not to migrate hoping to find a deep warm pool. Chances are there are none. They stick around their summer areas, only deeper. WHERE deeper? Any steep slope well off a bank, the lee side of a jetty (downstream side), behind a large boulder or rock ledge outcrop that blocks current but allows baitfish to swim around and into a bass strike zone. Keep in mind a cold bass isn't going to work hard to eat anything, and isn't going to chase much below 50 degrees. The meal needs to be right in its face.
I'll close this for now concluding an angler needs to motor upstream and stop short of those target areas. Cast upstream and guide your lure around the points into the calm pockets behind obstructions, but in "deep" water as opposed to shallow banks. Those laydowns look great now, but they are probably in the shallowest water. Get out in the river and fish deep structure changes even if that only means a depth change of 12".
I'll try to get around to backwaters and bayous tomorrow. I fear I'm beginning to ramble and need to go to bed.
Jim