Digging is more of an individual preference from what I have seen. Like Cleopatra said some do, and some don't. As for water, I have seen all of mine drink out of their bowl except for Popeye. I would suggest having water in their cage at all times. You should change the water frequently (some suggest every day, but evry other day or so should do), and give the bowl a rinse to reduce bacterial build up. That's what I do.
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Mommy of 6 Leopards
Milo(my male) Mongo, Raptor,and Spaz
My babies Popeye and Boo(named after Monster's Inc. Character)
2 Dogs
Baby a Peekapoo and Meshu a terrier mix
And a Cat named Mr. Kitty