One of your biggest issues is finding drinking water. You need to have at least a small supply of potable water stored for emergency use. Figure one gallon per person, per day for three days as a functional minimum. Triple this if using mostly dehydrated food. You’ll also want to have some kind of water filtration/sterilization kits. You should really have personal kits for each person as well as larger capacity, family or group sized systems. Cabela’s have several such options available.
One other thing, even with treatment, the water you may have may not look or smell that nice. A selection of powdered, pre-sweetened (sugared or sugar-free) will vastly improve the flavor and make it easier to stay hydrated.