Waterfalls are definitely one of the most beautiful acts of nature, as the flows unrestrained and fearless.

I did notice one thing though, your last line has 6 syllables instead of 5. I do know that some haiku's have more or less. But a simple suggestion to you for your last line; instead of "rocky" you could put "stone." Putting your syllable count back to 5.

Enjoyed the read, have a nice day.