Not sure because I haven't tried it, but I recommend you don't try it. Numerous papers show that it definitely causes dehydration, which can lead to extreme thirst, fatigue, and ultimately organ failure and, more seriously, death. A person may feel thirsty and slightly sluggish without water on the first day and experience organ failure by the third day.
In earthquakes, many people are not killed because of wound infection or crushing. In many cases, severe dehydration is one of the main reason.
Dunno. That depends on whether or not you live in a humid place. That said, the drier the place, the less likely you will feel like a person, given the fact that even if you live in a place with 100% humidity you would still feel like a piece of turd on an NYC sidewalk. It only gets worse from there.
I tried to not intake any water for 24 hours to prepare for a relatively massive operation where the dentist had to remove several out-of-place teeths that are incredibly hard to remove for instance. At the end of the day, water feels no less rewarding than when Andy dug his way out of Shawshank prison with a hammer.