Perfecto. Just the kind of advice I was looking for - thanx.
I'm not good with water management, because I'm a dip & drink (I never take a filter, and usually skip chemical treatment) person.
I've made most of my own gear, and one of the things I really like about my pack are the two bottle holders I crafted/sewed to the front of each shoulder strap between the buckle & sternum strap anchor point. Made from velco + a small bungy cord, they each snugly hold 20oz (.6L) gatorade bottles.
So not only is my water right there ready to either be used or re-filled without taking off my pack, but it also puts 2.5lbs (40oz) of pack weight center-forward around my sternum. (I will use these same bottles with my regular, commercial day pack.)
The couple of times I've done Whitney from the backside, I left Guitar with the two 20oz bottles and a 1.8L platypus, so I had essentially 3L. I recall re-filling the gatorade bottles at the spring, but left the plat in the pack.
That would make a total of around 4.2L over the 15-16 miles. But I also remember being out of water by LP Lake, but deciding to gun it to the store rather than deal with finding a decent source (not the creek) around the lake.
So I could have used 5L+ to get all the way back, which is .3L per mile. The r/t day hike is 20-21 miles, which would equate to 7L. No wonder you guys thought I was undergunned.
So what about this plan:
- 3L to the spring (bottles + plat)
- refill as needed @ spring on the way up
- refill as needed @ spring on the way down
Max would be 9L if I was totally empty at each point, but more likely total consumption would be somewhere in the range of 6-7L.
