To be honest, some might tell you to avoid the Na'Avi River ride. A slow moving boat ride that brings you face to face with an animatronic member of the Na'Avi tribe that sometimes isn't working right. Still, at its core, Na'Avi River is at least pleasant, quiet, and relaxing.
The same can not be said for...Khali River Rapids.
River Rapids is located in the Asia portion of the park behind the monkey island near Everest. It calls to you as a rushing river raft ride that will get you wet and on 90 plus degree day at Animal Kingdom, its like hearing the song of the Sirens calling to the sailors at sea.
I have ridden this several times and frankly, I have yet to find anything redeemable, imaginative, creative, or cooling for that matter. Sure there is one person out of eight that might get a little wet but if you are concerned for a massive waterfall that will drench you to your bones, this isn't it.
The ride is super fast, not in terms of movement but by the time you think the raft is finally going to pick up and deliver, you turn a corner to realize your ride is over and you are asking yourself why you waited in that hour long ine for nothing.
While there are not a lot of superb attractions at Animal Kingdom you could spend your time somewhere else and not feel as though you missed out on something. On the other hand, if you do spend your time waiting and you miss out on something else, you might be smacking yourself in the head.
Do yourself a favor, take the hour wait time and apply it to the 2 hour wait you didn't want to stand in line for Avatar Flight of Passage and then pat yourself on the back instead.