Change Log:

Added-
Experimental Crazy Waves! *CAUTION CRAZY*
Shallow w/Big Waves
Tsunami w/Big Waves
Atlantis w/Big Waves
===============================
Fixed Bugs

How to install:
1. Extract the water.xml from the archive.
2. Run OpenIV and open common.rpf
3. Open the "data" folder.
4. Open the "levels" folder.
5. Open the "gta5" folder.
6. Right-click on the water.xml file and select "replace".
7. Choose the extracted file.

How to install No Pedestrian's mod *OPTIONAL* :
1. Extract the popcycle.dat from the archive.
2. Run OpenIV and open the "update" folder
3. Open the "update.rpf" file
4. Open the "common" folder.
5. Open the "data" folder.
6. Open the "levels" folder.
7. Open the "gta5" folder.
8. Right-click on the popcycle.dat file and select "replace".
9. Choose the extracted file.

For Tsunami do the same, except replace files from the Tsunami folder.

For Atlantis do the same, except replace files from the Atlantis folder.

*NEW* Atlantis is Really deep! Check the Screenshots!

If you have any problems getting it to work without rebuilding, then try rebuilding as a last resort.

For the OFFICIAL VERSION of the game:
(thanks to @GTAMODDER)
Boot up the game and once you're in-game, go to task manager and close GTA V, it will then give you the option to go in safe mode or retry (Or it might ask you to sign in again), leave that menu open (Don't sign in yet if you got the option to sign in), now, install the water.xml using the above instructions. Once you've done that, click retry (or sign in and it should launch).

NOTE: The tsunami mod is a little buggy in terms of visual aspects. This is caused by the water being somewhere it shouldn't be. Some places of the city won't be flooded and higher parts of the map. You may get odd game crashes when dealing with pedestrians as their paths aren't made for underwater.

A backup water.xml has been included within the archive but still backup any pre-existing files just to be safe.

Requires OpenIV [2.6] which can be found here -
https://www.gta5-mods.com/tools/openiv

In order to use this YOU NEED OpenIV's ASI plugin. It will ask you to automatically install on first launch of the latest version. Without this you cannot use edited RPF's.

Not to be re-distributed anywhere else without my permission. Please don't use Ad links in video descriptions. Thanks and have fun!