clear underwater texture?

i was playing someones map and noticed how when you were under water, you could actually see where as default half-life water textures have very limited view distance.

how can i modify a water texture so you can see clearly through it when underneath?

water_tunnels01 is pretty clear water to use

$fogend and $fogstart both control the clarity of water. $fogenable 0 turns it off completely.

Still there’s some sort of underwater screen overlay which warps the screen a little.

That’s covered by a parameter in the link I posted.