Layer Lock Fade

Some people like to see only the layer that they isolate. As a default
option with civil 3d 2011 the locked non-isolated layers are faded,
although you can control the degree of shading from 90 to -90

I prefer to not see those layers.

The solution is to start your layer isolate command and type in on the
command line "S" for settings and change the option to "off",