r_lod
r_lod is a console variable available in all 
Source games. It allows overriding distance used in LOD. Higher distance, for example, makes models have less polygons, and textures appear smudged (i.e. less detailed).
Usage
Syntax: r_lod <integer>.
The default value is "-1" which makes lod compute normally. Setting this to 0 will effectively make every render as if you are close to them while a large value will make everything render as if you are far from them.
Note:Although turning r_lod off gives better visual quality, it also negatively affects your framerate (FPS), unless you have a more powerful graphics card.