Sometimes Sass seems like she isn't drinking enough, but that could be because she naps a lot during the day. When she wakes us from her naps and is ready to play she plays hard and then runs over and drinks, what seems like a lot of water, and then comes back for more play and tires herself out for her next nap.
I would just keep an eye on her and if you think something doesn't seem right make a call to the vet.
