Escher's waterfall

Keeping the MC Escher's series, I am posting here the WIP on the waterfall because it is being quite a job. It has been a 3-layer composition for making believe this was only one beauty fill render pass. It doesn't have yet these layers: 3 layers of ambient occlusion, the water comp layers (at least 2 beauty fills) and the background (very simple comp, free of impossible perspectives).
I hope you enjoy it!
Milton