"Bottled water is often simply an indulgence, and despite the stories we tell ourselves, it is not a benign indulgence. We're moving 1 billion bottles of water around a week in ships, trains, and trucks in the United States alone. That's a weekly convoy equivalent to 37,800 18-wheelers delivering water. (Water weighs 81/3 pounds a gallon. It's so heavy you can't fill an 18-wheeler with bottled water--you have to leave empty space.) Meanwhile, one out of six people in the world has no dependable, safe drinking water. The global economy has contrived to deny the most fundamental element of life to 1 billion people, while delivering to us an array of water "varieties" from around the globe, not one of which we actually need."
Tap water in the US is almost identical to bottled water. It's delivered efficiently and cheaply. So if you know you're going to need water someplace, bottle it at home and bring it with you.