Drinking water / hydration

[The Dark]

Unless I have gone even more blind than usual, while v2.2 includes diseases from contaminated water, it doesn't seem to include rules for water consumption/dehydration. It's certainly not in the Upkeep section (pages 148-150), since I read through that a few times to check. Has anyone come up with water consumption rules, preferably ones that account for exertion and/or temperature?