Is there a place there to float in inner-tubes?

There's a place where people play down where the old dock was. Not like a float trip but would work for lounging

You can for a float trip. Remember it's a river with some current. I'm sure you could be picked up at champoeg park boat ramp.

I recommend San Salvador outside St. Paul. There's a trail up river so you can float back down to the park. Long beach. Less boat traffic.

Yes but there are boats! Big open lake though, and I have seen people on them! 🙂

It has access to the river. You can use that to float! No lifeguard, so be sure to plan your float ahead of time for safety.