Issue 10, which this clones, was briefly fixed in versions 2.0.9 and 3.0.1, but water appearing in boats is back in version 4 and above of Entity Culling.

Steps to reproduce the behavior:

1. Go into a world
2. Summon a boat
3. Notice how the water in the boat is back

Expected behavior
No water in the boat.

Screenshots

Versions
Entity Culling: 4.0.0+ (tested with 4.1.4)
Forge: 2855
Minecraft: 1.12.2

Other
Singleplayer/Multiplayer: Both
Other mods (that are necessary to produce the bug): None
Other mods (that are also installed): None

Fixed in v1.12.2-4.1.5