Many thanks to Dune for his guidance, suggestions and ideas for the waterfalls. The node set up here is his which uses both a plane and a simple shape shader that form the falls/river. The water/falls/river are created procedurally and lie in a trench that is carried on forth as the downhill river.
I used four cloud layers to augment the falls/water/river, namely: Vertical Falls Cloud layer, Splash Cloud layer, Splash Mist Cloud layer and Bottom River Mist Cloud layer.
I also used three conifers, namely: NWDA/Walli Pine forest, jcinbama's Big Pine and dandelO's Larch.
I plan on creating a few more waterfall images with the next using a Water shader and a wider river - this being one of another set up by Dune. I'm doing this for practice to get a better handle on the use of the SSS and Plane.