Truck Bugout bag

[hatidua]

My worry is the water freezing and exploding whatever they are in.

I wouldn't worry too much about that. When I still had a place in Florida we'd freeze 1L and 2L plastic water bottles and use them to keep the fish coolers on the boats cool. We'd refreeze them solid every night and use them indefinitely - frozen rock solid and filled all the way to the cap. I never saw a single one break/crack/leak.