There's a lot of misinformation about water out there. Penn and Teller, on their show Bullshit!, will tell you you're wrong for drinking bottled water, that it hurts the environment and is just overpriced tap water.
Well... maybe. There is certainly bottled water that is simply bottled tap water. Is that so bad?
According to an ongoing AP investigation, U.S. hospitals annually flush millions of pounds of unused pharmaceutical down the drain. An estimated 250 million pounds. Thus, it is common place for there to be traces of birth control drugs, antidepressants, blood pressure medication, and more, in your drinking water.
And of course, chlorine is added to all water, in order to disinfect it as flows through the pipes to your house.
The cleanest water is distilled, followed by reverse osmosis filtration.