Half the stuff we hear about hydration is pure propaganda on ups part
Urine is not a sure fire way to tell your hydration. Certian vitamins such as vitamin b will make your urine bring yellow shortly after ingesting. Don't believe me drink water all day and than consume and energy drink. You can be hydrated perfectly and still piss very yellow
Also after traveling to different countries which have way hotter weather than us, I have noticed they drink way less water than what I have been told is acceptable. To top that off they consume massive quantities of alcohol after work. They don't pass out and die like according to ups they should. It has a lot to do with overall health and eating habits IMHO than just how much water you drink daily. Be smart, drink a bottle of water before work, drink water through out the day and throw a gatoraid or two in there. Cafine will not make u die, energy drinks will not make u die, and sugar won't either.