Water being such a rare and precious commodity, there are bound to be different grades and price ranges. I imagine that these grades would be based upon purity and cleanliness. The best water would have had no particles in it and no bacteria either. Can you imagine how many people, who couldn’t afford to drink the better water, died of Tatooinian Typhoid? Ideally, people would wash in the dirtier water and drink and cook with the clear stuff. If you were dirt poor though...even what little water you had wouldn’t have been good.