The Center for Y2K and Society suggests that Americans who do feelthe need to prepare use this guideline: store one gallon of water per person, per day, for 10 days.
The question is for some of these tactics like water boarding, where a detainee may feel as though he's being made to drown, or hypothermia or sleeping deprivation, these other things that in some cases may not be defined as torture by the people who are actually doing it.