I wanted to make some perfectly clear water-- the sort of stuff where you can see right down to the bottom. I managed to do this without any trouble, but have hit on a slight issue I can't seem to resolve: once I start swimming, if I look up at the surface, the water is no longer clear...

i.e.:
From above: perfectly Clear, can see the bottom
When Swimming: perfectly Clear, can see everything around you
When looking to the surface from underwater: dull blue, unless you're literally at the surface...

Anyone know how to solve this, if it is possible?

The color of the underside of the water plane can be changed by changing the color of the Underwater water type used by your water type. (Eg. DefaultWater uses DefaultUnderwater; changing the color of DefaultUnderwater changes the color of this plane.) Probably you know that already.

I believe the transparency of the plane is hard-coded. I looked for a game setting that might control it, but didn't really see anything. Might have missed it, though. Didn't see anything in the water type dialogue either. Also, looked for a .nif that might be used as the water plane, but didn't find anything. Ergo, probably hard-coded.

Thanks for the input. It's a little disappointing if it is impossible to change, but nothing I can't live with Thanks again

I know it's a whole other can of worms, but perfectly clear water would bring up the issue of realistic refraction. Water should look less deep than it really is, and looking should give you a circular field of view, because internal reflection at the surface limits the angle of vision. You may be better off with something less!

Ahh, but if you could make the water perfectly clear with a scripted spell...

I think the blue color is fine the way it is. It's the sky color mixing with the visual of you under water. I don't see anything wrong with that.