5thWiggle: Great links!
ScalyFreak: Very true, but I was only thinking of the initial survival period related to Stage 1 and 2 of most disasters. Unless we had a complete SHTF scenario where the world basically went to hell in a handbasket and took decades, or even centuries to recover, a Brita filter and a few spare inserts would be plenty. Especially given that the debilitating after effects of most disasters (loss of power, water, access to food, etc) only last 2-3 weeks at most before normal services are restored. Of course, if you were in a Level 3 or higher disaster, I think running out of Brita inserts would be the least of your worries. haha.
Oddly enough though, I'm actually looking at including something like this in my story to sorta mix things up. IE, the initial water filtration and supply situation is sufficient to meet the needs of the founding group, but quickly become overwhelmed and insufficient once a large collection of other bodies shows up. There's nothing quite as fun as knocking your characters to the ground, and then kicking them when they're down.
hehe.
