Here are a some tests that I did to create water for our Serengeti, I made them a while back but forgot to post them up. I made these by applying an Ocean shader to a polygon plane and I then used key frames to play with the timing.
Here is an earlier test that is a bit too strong for a calm wilderness environment
And here is test with a lake that has a calmer flow. This is closer to what will appear in the final piece.