Hi,
I just made my first hazard water after reading this thread:

acid-water-t1260.html

I noticed I can shoot portals through the surface of the water. Is this typically avoided by having the surrounding faces of the 'pool' a non portalable material, or by some other means?

If I recall correctly, the official maps use a non-portalable version of the materials.

However, you could also use a func_noportal_volume if you wanted to.

Yeah, Valve uses the metalwall048e texture. But you can use any non-portable texture you want.

Just curious, what texture are you using underneath the water? (what texture is at the bottom of the "pool"?) I've always used a the metal texture with the green algae looking stuff on it for the bottom and sides of water hazards so I've never ran into this issue before.