I take a 2 litre bottle of water with me to work each day and refill it by the end of the day. With milk included i'm going to guess on a rest day 3-4 litres and a training day 4-5 litres. I think i'm becoming addicted to water! I get headaches on the days i don't drink enough and avoid coffee and alcohol (which is a big effort for a 21 year old) which would explain why theres always room for more water