This mod prevents the Vampire race from drowning. I thought it was kind of silly that undead creatures die from drowning while there... welll dead so don't breathe.
Basically this mod adds the WaterBreathing abillity to Vampire's with the exption of Argonian's. It prevents playing the breathing sound when resurfacing, only to the Vampire's. I made the abilities unique so there shouldn't be conflicts with other Vampire mods. Unless they do something similar to the Vampire Race.
Make sure that file selection is enabled in the SkyrimPref.ini, you can find the ini in you’re Documents\My Games\Skyrim. Add the following if file selection is missing.
Then copy the Vampire's Underwater suffocation FIX 1.1.esp to the data folder in the game directory. I assume you know how to find you're game directory!