That's right, the water for the bug out trip is not usually a problem around here. In a worst case (the creek is dead after a quake) we can reconsider the bug out location to another one on the shore and make a simple distiller. That plastic 58oz bottle was decided as a most lightweight container fitting that backpack's pocket and as a good resource for various improvisations (it has texture reinforced thick flat sides). I have steel bottles in other 2 bags.