I'd be happy to help as much as I can. That image was actually made quite a while ago now, before there was even a water node or shader to use. So I used a basic reflective shader and a power fractal on ridged multi-perlin, if I recall. Approximately 3-6 meter wave scale (feature size). If I can find the .tgd I'd be glad to share, but it was made so long ago it will probably not render correctly anymore. I'll let you know if that works out...
Funny enough water is much more advanced now, especially with transparency, not to mention the "patchiness" settings (which are often a must on larger bodies of water). Nonetheless I've always had a fondness for this one too. And to think I'm still not satisfied with that St. Helens scene...
- Oshyan