I can only drink so much...

I went to mythbusters, they suggested this amount is perpetuated by the industry that sells bottled drinks, and that you can count a lot of other things towards water intake. I eat a lot of salad, mainly water, drink tea and coffee. I cut down regular water intake and I'm fine. I drink about 1500ml a day. Thats2 large sport bottles filled from the tap. Plus one more if I go to the gym. Keep it nearby and sip it as you go. Easy.

From Livestrong:

Many detoxification diets include the consumption of large amounts of water, ostensibly to help the body "flush out" toxins that are stuck inside. Detox diets may also include supplements intended to help your body eliminate chemicals and heavy metals from food intake. However, according to Katherine Zeratsky, R.D., L.D, for the Mayo Clinic, your kidneys and liver efficiently and effectively remove most ingested toxins. In fact, habitually drinking too much water can actually reduce your kidneys' ability to filter out things that your body can't use, according to Dr. Stanley Goldfarb of the University of Pennsylvania.