Right now the water is a single plane at one elevation. If you are far more skilled than me, I suppose you could make your own water plane of any size and place it anywhere you want! That would require knowledge of the water shader, I suppose, and what goes with all that ( textures, etc) I have read that they eventually want to do much more with the water options in the future, but they haven't disclosed what those options will be that I've seen. I would imagine the things you described will be among them though. We just GOTTA have waterfalls!
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