The “Greatest Generation” lived in a world of cans, not bottles. During World War II and for decades after, emergency water was provided in grey cans that were used by the military, as stock for civil defense shelters and for provisioning life boats. Some obvious disadvantages were weight and short shelf life due to corrosion and can materials leeching into the water. (Were can openers provided for life rafts?)

Collectors of all-kinds-of-random-stuff will appreciate knowing that these cans pop up with some regularity on ebay.

Makes those wasteful bottles look better, hey? Today’s military issue “emergency water” is packaged in 4 oz. flexible pouches which are easy to move in bulk and have a 5 year shelf life.

Not that the pouch has in any way replaced the bottle. Because pallet-loads of bottled water are expedient to package and ship in large quantities, the pouch is reserved for specific emergency situations, like a survival kit for a life raft. Bottles are movin’ out in this 2005 pic from slagheap on Flickr. Here, U.S. Navy Seabees organize bottled water for distribution in Biloxi, Mississippi in the aftermath of Hurricane Katrina.