If there is food in with them, they will always need water, no matter how old they are. They need the water to help swallow their food.. otherwise they could choke and die. Although they don't necessarily need swimming water 24/7, they need a deep enough bowl of water so that they can submerse their heads and clean out their nostrils.
When I raised my Toulouse babies, I put a rock in the water dish and put shredded lettuce in the water. They would chase it around and it would occupy some of their time, they also love chopped carrots (very small) But watch in cause they will poo orange..
I would take mine outside a couple times a day and let them swim in a water dish, then on the bigger things. They loved it. I think that got them out of the drinking bowl a bit better.
I currently have them on bran as that is all I had at the time(out of hay) and they are now covered in the stuff..lol.. SO swim time tomorrow in the bath tub should be a nice little mess for me..lol.. Ill pull the food then until in the morning... Thanks for the advice!