Now that we’ve covered size, shape and color theory of these necessary waterways, let’s move onto the modeling portion of this tutorial.
Our Main Ingredients are the following:
The “WATER”
For water, Woodland Scenics has been selling a horrendously overpriced product called “Realistic Water” which is actually just Acryllic Glazing Liquid used for painting light layers of paint on a painting. Learn more about Acrylic glazing liquid here. You can get this stuff by the GALLON for half the price of the bottle of WS product at Blick Art Supply.
This stuff is smelly, but not noxious. I would suggest opening a window if you want to model while you pour this stuff. It takes about 24 hours to dry and ONLY pour in 1/16″ depths. In all honesty, you really don’t need to pour this stuff deep, it looks fine on the surface.
Paint
Using color samples directly taken from the river via the satelite photos I posted in my previous article, I came up with this list of “necessary colors”
You can explore the ‘zillions’ of other colors out there; here.

The Colors I used to paint the River are mostly from Benjamin Moore’s “Color Sample” paint jars. These 3oz Jars cost about $3-4 and cover a 2X2 foot area if used completely. Yu can get these at a well-stocked hardware store, or a Home Improvement warehouse.
The other colors in the 2oz containers are the $1 craft paints you can get from any craft store.

The Colors Are:
-Dark Green: “Mohegan Sage” (Ben #2138-30)
-Tan: “Monroe Bisque” (Ben# HC-26)
-Sky Blue: “Yarmouth Blue” (Ben#HC-150)
-Dark Brown: “Clinton Brown” (Ben#HC-72)
Craft Paint:
-Navy Blue
-Sand Stone
Optional Regional colors:
for Clay rivers, use “Terra Cotta”
for black use “Asphaltum” (which is a very dark brown. Avoid black at ALL COSTS)
Prepping the Riverbed, Lakebed, or Harbor.
You can approach this two ways:

1. Involves laying down a flat piece of particle board, adding the riverbanks in, then painting the surface and adding the acryllic glaze, then finally adding ripples with acrylic gloss medium. This is good for wide, deep rivers, harbors, lakes and channels.

2. For creeks and shallow or seasonal rivers that vary wildly in depth year-round, or a river that has a lot of sandbars or islands, try this method: (READ MORE) <-Will be written about tomorrow
Painting Technique:

Gently blend your sand color and your brown colors the farther from shore you get, then blend the brown into the green, and finally add navy blue in the center if this is a deep river. (See the color chart above)
Let this dry overnight to see if the colors you blended looks satisfactory. Make sure that all blends between colors are SEAMLESS, and don’t have a distinct break in color, unless you’re modeling underwater vegetation like Algae in the deep log pond (above) or brown coastal seaweed.

I think its great you are doing this how-to on water, I still haven’t pored water yet on a layout, but you are doing a great job at making me less unsure when I do attempt it. Keep it up.
I too found this extremely useful. I’ve already done 1 small diorama water scene, and am preparing to do another. I keep referring back to this tutorial. It’s the best I’ve found for painting realistic looking water. Thanks!