The trash compactor walls are simple func_trains and the water has very similar logic. Those entities are used a lot throughout the game so I find it odd that it only occurs in these particular instances.

Still, it's likely that this is a combination of engine and renderer issues. What graphics card do you have? You could try going back to an older video driver that has the same date code as HL v. 1.0.0.9. and see if that helps.

In any other case, the devs clearly fixed this issue with v. 1.1.1.0, so there is your answer to how to fix this. I know this might break some older mods, so you got to determine for yourself what is worth the most to you.

Thanks for the reply. I've tried two graphics cards. The nvidia GTX580 and the ATI x850xt. The ATI card is the oldest card I have at the moment. Both exhibit the issue. I played through the game using software mode and, as far as I could tell, those were the only two instances of the issue. Other areas where water levels are changed worked fine and the trains in On A Rail worked as well.

The reason I wanted to avoid 1.1.1.0 was because I noticed that the lighting and weapons animations look better in older versions. Unless my eyes are playing tricks on me, the animations look clipped and don't seem to loop properly on the later patches.