This small stream began as a CAD line file provided by Ozaukee County. World Construction Set inputs the data as an ArcView shape file, storing it as a "vector." Creating a realistic stream from this line file is a multi-step process. First, a stream bed is dug into the DEM. This bed (a terrafector) can vary in shape, depth, roughness, surface material and approach slope. Then the stream is filled with water using a stream effect. Factors such as water color, wave height, beach height, reflection and water depth can be set to vary with the steepness of the stream bed.