Lots of grey areas under Ohio's laws regarding access but the best way to lay it out after several years of research is this.
State owns the water and the wildlife that can move along rproperty to property.
Landowners own the bottom of the stream as they are paying taxes on this land.
Landowners have the right to allow/disallow "hunting" of wildlife on there property, ( think Deer hunting where state owns the deer but private owners alllow who has access to hunt them)
Only a handful of larger waterways within Ohio's boundaries do the landowner only own to the waters edge, and that shifts constantly. This includes the very lowest of the Muskingum, the lowest few miles of the LMR and 1-2 lake erie canals that are all deemed "Naviagable" by Ohio Law.
No where is there a public right of way to/on inland streams.
You are right to a degree that the state owns a right of way about 50 ft from the roads center line on state highways so there is a small bridge access avaialable but, Im pretty sure where ever you park, would be on private land so that makes that harder to navigate as well.
Last point is that yes, you can float on some rivers and larger creeks but the second you anchor or touch bottom, you are tresspassing. Oh yeah, if the stream has a maintained fence across it, it is considered private and you may not ( without breaking the law) cut or go around such fence.
There are many exceptions to the above laws and thats where it gets rather sticky, the real problem is that in Ohio, there are several places you have to combine laws to get the above facts which is why its best to float and not be seen, all camping on all Ohio waterways is on private property, even sand bars so keep that in mind.
Access has been and always be a sore spot for Ohio anglers , we seem to be losing some everyday and it wont be long, all fishing even in Ohio's river will be like Europe and will all be private.
If you have more specific questions, I can answer those as well so just send em my way.
Salmonid