It's a pleasing photo with both static and very dynamics aspects. The rock texture and the blurry water are "just right".
Quite on the contrary, I found it very disturbing... and that is precisely why I like it so much (I agree on the other parts or your comment, however).Having been there myself many years ago, I too found it disturbing but very expressive of the power of that beast! I would never have thought of turning it into "black water," but it really works. Bravo!