Much has been written about the distinction between ある and いる, such as which is appropriate for robots or corpses.I know water is usually referred to with ある, but in a sentence such as 'この川にはいっぱい水が「ある/いる」', where the speaker is talking about moving water and not a source of water, which verb is correct? If a person wanted to indicate that the water was stagnant, would the use of ある get the message across, or would 溜まり水 or 止水 be necessary to communicate the meaning?
The question is not one of 'movement', but rather 'animacy' - i.e. how close to having human consciousness the entity in question is thought to be. Humans are of course close to human consciousness, as are things like gods or fictional sentient species, so you use いる. Pets and other animals can go either way, depending on how much humanity the speaker wants to grant them. Inanimate objects are always ある, since they are far from having human consciousness.
So water will never be いる unless you want to ascribe some kind of spiritual personal sentience to it. Normal water will always be ある.