Just because it's in our imagination, does that make it any less real?

Master Roshi disagrees with this message, and he's a master so I'll side with him

The stream looks too consistent. I know chameleon's and I believe some other lizards have a problem with standing water and need to have running water (usually in the form of circulating waterfall bowls). He probably doesn't see it as water but as a branch or just a column