You should always have a shallow water dish, always.
What i do as one of my torts hates a bath, i put a folded of flannel in the water. I have found he pears over the side and drinks freely and is less stressed, also his body is still submerged but he feels safer. Also if he is in the water he knows he`s got a little island to get on, but you must keep up with the baths. Mine get a soak at least 3 times a week everyweek its so important to keep them hydrated. Even if you don`t see him drink he still absorbes the water.