Formula for rough amount of water to carry on hike?
Is there a formula which can be used (I'm thinking one that gives amount of water needed factoring in time or distance covered and temperature) to roughly work out the amount of water that needs to be carried for a particular hike?
Obviously this will be a very rough guide - I know how much I generally drink, but I tend to drink quite a lot, I'm wondering as a rough approximation I can give to others to form an idea in their head.
Is there an "official" such formula, or have others coined their own that they use?
This post was sourced from https://outdoors.stackexchange.com/q/1614. It is licensed under CC BY-SA 3.0.
4 answers
You are accessing this answer with a direct link, so it's being shown above all other answers regardless of its score. You can return to the normal view.
I walked Hadrian's Wall recently carrying an 18kg backpack. It was hot, sunny weather for six of the seven days. I had a 2 litre bladder of water and by the end of each day I had ran out of water. That was not a nice feeling walking the last couple of miles without water. I have now upgraded to a three litre bladder.
This post was sourced from https://outdoors.stackexchange.com/a/3052. It is licensed under CC BY-SA 3.0.
0 comment threads
The answer to this question depends completely on the weather and on how plentiful water is on your route. In the Sierra, the answer is typically zero, i.e., there is almost never any need to carry any water on your back. (Nor is there any need to purify water in the Sierra; see https://outdoors.stackexchange.com/a/4058/2169 .) When you're thirsty, you stop at the next stream, lean down and scoop up some water, drink it, and then continue hiking. There is the myth that "thirst is too late," i.e., that you have to drink lots of water because you'll be dangerously dehydrated by the time you actually feel thirst; this is an urban folk tale.
If you're in a different environment, such as a hot desert, the answer could be totally different. For example, temperatures in the low-elevation areas around Palm Springs, California, have been recorded as high as 50 C (120 F). In these conditions, the amount of water you need is infinity. That is, your body's ability to cool itself is simply overwhelmed, and you may die no matter how much water you drink, if you're outside in the hot sun at midday. In this kind of heat a few years ago, one hiker was found dead, sitting peacefully on a rock, 100 meters away from a tennis court, with a full water bottle in his hand.
This post was sourced from https://outdoors.stackexchange.com/a/5180. It is licensed under CC BY-SA 3.0.
0 comment threads
1 liter per two hours of hiking. If camping overnite add 1 liter. If over 90F add 1 liter. Also good idea to hydrate before hike and to take water filter along in case other water is available.
This post was sourced from https://outdoors.stackexchange.com/a/20695. It is licensed under CC BY-SA 4.0.
0 comment threads
The rule is 3 liters per person per day. You may get away with 2 liters if it's not too hot and you stay moderate. Keep into account that your "normal day" intake is skewed by the contribute brought from food. If you eat food with less water in it, which is likely during a hike, your need for actual water is higher than the one you experience in your daily life. Add the physical activity and you get the idea.
This post was sourced from https://outdoors.stackexchange.com/a/1629. It is licensed under CC BY-SA 3.0.
0 comment threads
0 comment threads