Create/Edit Water Preset
This window can be accessed by going to the top menu bar and selecting World → Environment Editor → Water Presets → New preset or Edit Preset 25). The windows are almost the same, except that in Edit mode, you select an exiting preset to modify, while in Create mode, you supply a new name to use and start out with default values.
Fog and Wave Tab
Water Fog Color:
Opens the Color Picker
so you can change how underwater fog appears.
Opens the texture picker
so you can set what normal map
is layered across the water to determine reflections and refractions. A normal map is a specially-prepared image to simulate depth, but you can use any texture here.
Fog Density Exponent: Controls how dense the water fog is and how far you can see underwater. Has no underwater effect when Underwater Fog Modifier is 0.00.
Underwater Fog Modifier: Boosts or lessens Fog Density Exponent when you arere underwater. Has no effect on the water's surface.
Big Wave Direction: Controls where and how fast the large-scaled version of the normal map moves in the X and Y directions.
Little Wave Direction: Controls where and how fast the the small-scaled version of the normal map moves in the X and Y directions.
Controls how much light is reflected at different angles. See this page
for more information.
Fresnel Offset: Controls how much light intensity is reflected.
Refract Scale Above: Controls how much light is refracted from looking above the surface of the water.
Refract Scale Below: Controls how much light is refracted from looking from below the surface of the water.
Blur Multiplier: Controls how waves and reflections are mixed. Higher values appear brighter.