Ducks are flock animals, and as such, should have at least one other duck to keep them company when you can't. It wouldn't be fair for her/him to be alone.
If a bowl of water is sufficient for some ducks, your ducks will be spoiled rotten with a stream! In my opinion, streams are better than ponds, because all of the nastiness gets washed away instead of sitting in the pond to rot.
Also, don't just put her in with the chickens, they'll peck her to death if you aren't careful. I needed to wait for three days to put my ducks in with my chicks, and they still went after them!
It really is better to brood and house them separate, but it can be done together, much to the dismay of the cleanly chickens.
They hate being wet, and ducks are the wettest bird EVER! Geese (who are much bigger) don't even make as much of a mess.