How can I get my indoor cat to drink water?

Don't worry. My cat is the same, she is outdoors alot and it doesnt rain hardly ever where i live and my cat hardly ever drinks, it seems like her water bowl never goes down but i know she drinks, my cat likes to drink when no one is watching her for some reason but sometimes i see her and she only takes a few sips, no cat drinks that much, they no how much they need so dont worry :)