instructions

Instructions
- Before opening the game, run OpenIV and go to edit mode, Navigate to common.rpf/data/level/gta5
BACKUP water.xml in case something went wrong. 
And then replace it with the one included in the archive. 

Then open game and load the underwater_base file with the editor.
You need Map Editor by Guadmaz https://it.gta5-mods.com/scripts/map-editor,
F7 -> load -> xml -> underwater_base