I don’t know how a Riverboat ever made it up the Cahaba north of Hwy 80. I have to get out of my kayak if I take the wrong channel. Why it would be more shallow now I don’t know. It had to have been a small Riverboat, but large enough to hold cargo and make the trip worthwhile. My ole man said before they damned the Alabama you had to really know the river or you would run a ground in a small boat, or hit the rock bars that were just beneath the surface. The river was MUCH different pre 1960’s.
Sorry to highjack the thread but I think the Op got good information several days ago to make his decision.