If I may, my troop (which happens to be my roomate, and boyfriend)go hiking a lot, and dont like to carry water. We have purchased a water purifier pump.

We each bring 1 empty 1.5L water bottle each, then we just have to pump and drink.

I live in Canada in the Rockies, so I don't know what the water situation is like down there? It could be like an american asking me if I have a dogsled, like Rick Mercer said on TV. But if you do have any access to water, there are many new techniques to purify, including the steriPEN.

check that one out, I just did today, and am pretty impressed that major towns and cities use the same principle of Ultra Violet light to sanitize H2O for drinking.