Searched this on the web. Most these answers don't seem very scientific, are all over the place, not thorougly researched. Still, using Nate Silver's method, we can add them all up and get a rough idea. - dc

Live Strong dot com - Generally speaking, people can only survive about a week without water.

Scientific American (introductory paragraph before you have to pay)

Life's Little Mysteries: (In the wilderness) After 3 days, you need water or you'll perish. Some people have survived 8 to 10 days without water.

Waterpage.com: A person can survive only three to five days without water, in some cases people have survived for an average of one week.

How Stuff Works - Survival: Assuming you're in reasonable shape and in ideal conditions -- that is, not in the heat or cold and not exerting, a human can probably live for about 3 to 5 days without any water. Healthier humans can live another day or so longer.

Answers.com: A human body can survive 8-14 days without water depending on the person and how fast sweat, urine, and tears are leaving the body

A 97 year old woman survived 8 days without drinking or eating anything under the rubble of her home after earthquake occurred in Iran in January 2004

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