Far be it from me to discourage anyone from storing lots and lots of water, but lets keep some perspective here.

Judging from the water bill, we'd be hard pressed to use more than 15 gallons per person on a normal day. That includes cooking, washing clothes and dishes, watering the garden and topping off the kiddie pool.

When it comes down to it, you really need water for drinking and everything else is optional. Unless you're emergency food supply is nothing but pasta and rice.