Here is a vitalized example of the waterfall. This level is not playable (player doesn't move), it just shows the water. The water normally looks better on a lower resolution (fullscreen).
What an ingenious way of showing things! Aptennap's suggestion is good, but also I think it would also look a bit better if the lower half were offset a bit instead of just going straight down.
Ah yeah Aptennap I came to this page to post exactly that advice! Waterfalls look better if you apply some effect to the bottom portion. I personally favor using both "half speed" animation & 50% more semitransparency.