I apologize in advance as I'm sure this is available somewhere, but I can't find it conveniently.

What is a good resource for estimating how many ounces of water per hour you should drink, depending on hiking conditions.

I'm planning a clockwise thru-hike of the Tahoe Rim Trail in early October. From Tahoe City to the end at Kingsbury grade south,(about 80 miles I'm planning on doing in 4 days, 3 nights) the mileages between reliable water sources are approximately 12.5(Watson Lake), 17.2(Gray Lake), 5.6(Snow Pond), .71(Galena Falls),4.1(Ophir Creek), 14.35(Marlette Lake), 8.8(Spooner Lake), and 13(Kingsbury Grade North).

I'm just trying to figure out how much water I need to be carrying. Assuming daytime highs of 65 degrees with lots of exposure and plenty of elevation gain and loss.

Thanks for any advice or links to relevant threads.

Here is a very well developed method used by Ultra-sports and general sports fuel & hydration ratios:

Hammer Nutrition:


http://www.hammernutrition.com/knowledge/the-10-biggest-mistakes-endurance-athletes-make.1273.html?sect=essential-knowledge-section

I live in south lake and could help out with some water and resupply drops that time of year. PM and see what we can come up with.

Joel

The problem with trying to answer this is that different people have wildly different preferences about how much water to drink. One guy recently posted on BPL saying that in everyday life (not while backpacking), he drinks 88 oz of water an hour. I think it was probably a joke, but others seemed to take it seriously. I probably represent the other extreme, because when I've said how much water I drink, I've had people get mad at me and tell me I was being irresponsible and encouraging innocent people to die of dehydration.

Back in the 50's, they'd take army recruits and make them hike all day without water, to toughen them up. Hikers used to put pebbles in their mouths to ward off thirst, or chew oxalis leaves. We've gone through an immense cultural shift in the last couple of decades, and it's reached the point where libraries and symphony orchestras are afraid to tell people they can't bring in a plastic bottle of water, because people will accuse them of making them get "dehydrated." Drinking water has an aura these days that's as holy as driving a Prius.

Ben LOL You're d*** right! I gotta have my H2O! :) I was in Angeles National Forest 2 weeks ago and made camp by a creek. I almost drank it dry!

Edited by socalpacker on 08/06/2010 23:08:22 MDT.

Too funny, Ben.

> Back in the 50's, they'd take army recruits and make them hike all day without water, to toughen them up... ...it's reached the point where libraries and symphony orchestras are afraid to tell people they can't bring in a plastic bottle of water, because people will accuse them of making them get "dehydrated."

James - what I have found I need in similar conditions is 2 liters of water to get me through half a day of hiking (say-6-10 miles). That's assuming I drink up before I start and then end at a water source. I'm average size and weight, and I would guess I sweat a little more than most. If I were looking at a longest waterless stretch of 17 miles (as you seem to indicate), I'd want to be able to carry 3 liters for sure, maybe 4. I know I'd be thirsty the last few of those 17 miles with 3 liters, but not desperately so.
Great time of year for that area, by the way.

Thanks for all the input.

That Hammer Nutrition link has a lot of interesting information.

I'm not a scientist, but I think, assuming daytime temps of no more than 65 degrees, I'll be okay with the 3L of water capacity I'll be packing. I figure the 17 miles I have to cover will take me at most, 6.5 hours, and more likely 5.5-6 hours of hiking time. I figure I can get by on 17-20oz of water per hour. So that's 105-120oz of water. I figure at my first source (Watson Lake) I can take a break and drink a half liter of water and hydrate myself for the first hour.

The complicating factor is that as it stands now, my itinerary has me stopping for the night halfway through my 17 miles, so while it will only be 6 hours of hiking time, it will likely be 17 hours of total time that my 3L has to last. The majority of that will be resting or sleeping, so my water loss will be minimized, and I'll go no cook that night to save water. I may just buy a 1L bottle of water in Tahoe City that I can then throw away when I reach the Mt Rose camping area.

I wonder if the moment that hydration become a measure of virtuousness coincided with the moment that somebody figured out a way to bottle tap water and sell it to people?

My experience has been that I use 2-2.5 liters for a night. That's dinner, breakfast, and drinking water. If not cooking at all, then I'd say 1.5-2 liters.
So camping in the middle of a 17-mile waterless stretch would change my plans for sure. I'd want to start with 4 liters if I were doing that in October Tahoe conditions. And I'd expect to be pretty thirsty by the end.

Yeah, I'm actually ordering another 2L platypus by now. It weighs. It will add a whole .43oz to my baseweight, but make me feel much more water-secure.

I'm not keen on the idea of just buying a 1L bottle of water at the Save Mart for the second part of my trip as my pack capacity is maxed out right now and it would be tough to find a place to carry another 1L bottle. The 2L platy's would balance each other nicely in the side pockets.

I'll be going no-cook as I'll be bringing a sandwich that I'll buy in Tahoe City for dinner. Breakfast is Perpetuem, so that's water-neutral.

Combine that 4L with the ~16oz of water I'll be mixing with my Perpetuem, and I'll be starting out with 4.5L of water for that 17 miles, 17 hour stretch. I might be thirsty by the end, but I don't think it will be life-threatening.

It won't be fun carrying 25lbs in my frameless pack for the start of that stretch, but I'll survive, I think.

Thanks for the advice.

Edited by jrmacd on 08/10/2010 06:38:12 MDT.