Would it be possible to edit the interior water so that it could be placed vertical and would not effect actors in any way except to reflect them ?

does water even reflect actors at all? i thought it was only sky and trees (and nothing if used in interiors)

even if you could, the player would either see nothing as their reflection in 1st person, or a pair of creepy floating arms

Water doesn't reflect and having it sideways creates a lot of complaints in the CK. I have sideways water serving as a magical portal and every time I open the cell in the CK it sets off a bunch of red flags. However ingame I've had no problems.

I changed the collision flag in the water nif file of course I created my own and changed that one. It seems to work fine sideways with no errors.

I have exactly the same problems, but in game its fine, makes you think putting errors in are pointless.