You may want to take this with a grain of salt as I have only been uo Whitney once, a day hike in June of this year, but I can tell you exactly how much luquid I took in between Trail Camp and the summit and the return, one quart of water plus a 20 ounce bottle of Sobe Green Tea (sweet and minty, I love it). I didn't suffer any ill affects, so I assume this was plenty. I did give a second quart of water I had to another hiker, but I don't think you can count on fellow hikers as a reliable source. I saw several hikers who looked like they were really hating it. I even suggested to a couple of them that they should turn around.
