This is a beautiful picture, however, I am not sure it conveys a feeling of power but rather the opposite; it appears to be a calm and slowly flowing stream, undoubtely as a result of the long exposure time and perhaps overuse of neatimage or noiseninja? I'll give it a 6, but would have given it a 8 or 9 if it had better met the challenge.
I tend to feel that these shots are a bit overdone but this specific capture is really well done. I like the little splashes of color from the leaves in and out of the water.