It is widely known among veterinarians and cat behaviorists that the worst possible place for your cats’ water bowl is near their food. (Actually, the very worst would be near the food in the same room as the litter box). Instinctively cats prefer to find their water source some place other than near their food as in nature bacteria from their dead prey (the cat food you give them) can contaminate their water. Oddly, though, most cat owners seem not to be aware of this and place their cat’s water bowl or cat fountain next to the food bowl.
It is for very similar reasons that cats prefer moving water. In the wild (and cats are not very far removed from the wildness of their ancestors) still water often harbors harmful bacteria. Moving water is safer. This may be why many cats like to stir their water bowl with their paws before drinking. It satisfies or at least, partially satisfies) their instinctively hard-wired drive to drink from moving water.
Cat behaviorist Mieshelle Nagelschneider, in her book The Cat Whisperer says: “Cats are drawn to running water, so if your cat doesn’t seem to be drinking from his bowl, try a fountain. Cats are notorious for not drinking enough water, and these simple prescriptions can make it more likely that they will get what they need.”