I have heard that the 'Tangy used to be one of the midwest/east's best smallie rivres. I don't know why people say used to be..... My real question though, is like you asked--which ones are wadeable. QUOTE]
The Scioto, Walnut, Olentangy and Alum are wadeable everywhere that I've tried to fish them. Same goes for the Mad and Clear Fork. In most of these rivers, as long as you're away from a dam of any sort and not fishing during spring high water, deep water is anything over your waist and there is little FAST water. By all means take precautions, but these waters -aside from spring floods - are pretty tame.
I had a neighbor that said he used to routinely catch 3+ lb. smallies out of the Olentangy in the 30s, 40s, 50s give or take a couple decades. He blamed the drop in fishing quality on the creation of Delaware Lake. There's been a fair amount of bed loading and the spring discharge may disrupt spawning grounds. Pollution has been an issue as well.