Modular River

For the base of the river pieces, I had some press board that was used as packing material in a bookshelf we bought. I cut some at an angle to act as bends in the river
After a couple failed attempts at cutting the banks out of insulation foam freehanded, I decided it was best to trace it out on a cover sheet. 
 Just in case, I had some one double check my work. ;-)

 So, I used the hot wire cutter & traced my paper stencils. To vary the landscape some, I made little hills & valleys across the top of pieces as well.
The waterfall piece is much the same: stacks of insulation foam attacked by the hotwire cutter.
To give the rock faces a texture, I scored lines into it using the sharp end of a bamboo skewer
I added some stone/gravel to the river banks
Then primed all the pieces with a mix of Gesso & acrylic paint

I painted up the rocks with a dark brown paint, then a couple lighter color dry brushings
 Then painted the river bed to mimic depths & a green base color for the flock to come

To make cattails, I rolled some Sculpey oven bake clay into a thin rope

Flattened it a bit & cut into small sections that would fit nicely on sections of wire. 

I placed the wire in the center of the piece of clay, rolled it around the wire & baked accordingly.

For trees & shrubbery, I set an empty grape stem outside in the sun for a couple of days

then glued on varying colors of Woodland Scenics clump foliage.

The main grass is also a Woodland Scenics product called 'Blended Turf' & then I added patches of static grass & a browner turf.

Here's some shots with the plant life added; I used some spanish moss to be roots growing out of the crack in the rock

And now for the water -- since there was so much area to fill in, I decided to go with silicone caulk as my water instead of expensive name brand water effects. One thing I learned the hard way, caulk labeled "Clear" isn't really clear. It is cloudy/milky/translucent. "Crystal Clear" is what is need to represent water.

While the caulk was still wet, I dragged a stick through it in short strokes to make it look like the river was flowing.

To make the waterfall, I applied caulk to some plastic wrap in the approximate length/width I needed, added some 'flow texture' and let it dry. After it was completed cured, I fit it onto the cliffs & cut away what didn't fit. I then added a line of caulk to the edge of the rock cliff to 'glue' the falls to it. (The cattails shown are just pinning the falls in place so it wouldn't slide off before the caulk dried.) I attached it to the bottom of the falls this same way.

Once the falls were attached, I filled in the upper part of the river, extending the caulk over the falls to help blend the two together.

Using the 'Clear' caulk that is really milky colored, I dabbed on extra peaks to the texture of the water to look like the splashes & foam of rapidly moving water on all the pieces of the river. More on the faster areas like the water & narrow points in the river, and less on wider/slower parts.

The falls looked a little flat, so I added some quilt stuffing behind it to represent mist.

And finally, I put together a quick bridge to help with playability. This is just done with craft sticks & a mix of brown washes.