I totally agree with your statement.. Who claimed that a liter was adequate? In the desert, the more water, the better (at least until you are dealing with flash floods - that is another story. You would be surprised at how many people drown in the desert).

One of my classic survival texts, [/i]The Survival Book[i] gives the following estimates in a chart on page 14. This is for one person doing no walking and maximum temperatures of 110F. With no water - 3 days survival; with one quart - 3 days survival; with 2 quarts 3.5 days; with 4 quarts - 4 days. You can last 7 days if you have 20 quarts (5 gallons). The text points out that having just a little water doesn't do much good.

My desert experiences tend to confirm their conclusions; some years ago, in Tucson I and a companion set off on an uphill hike at noon on a sunny day with temperatures in the mid 90's. Time was of the essence (SAR). We carried 2.5 gallons of water between us. We had a good source of water 7 miles up the trail and we were both familiar with the trail and the surrounding country.

We arrived at our stream completely out of water and quite thirsty. We drank our fill. We refilled containers and continued our assignment. We shortly happened upon our victim, who was also quite dehydrated, along with several traumatic injuries... It is quite difficult to stave off dehydration when it is hot and you are working hard. An unlimited supply of water is the best thing. Even three gallons can be cutting it close, but how much can you reasonably carry?