[mikekchar]

On the other hand, if I have fuel, then I may be able to get water in the form of rainwater or other potential water sources -- boiling the water for safety. For me, that's one of the big things that people overlook when they are preparing for disasters.

But I would say definitely store food and medicine. Keeping your energy levels up is important for maintaining your health. Getting ill is just another way to die.

[AstralStorm]

You need chemical treatment and not boiling for rainwater. It is often chemically polluted because we're still burning contaminated hydrocarbons, typically with NOx or SOx (nitrates or sulphates). These are rather unhealthy, but in a short emergency it's fine.

You definitely want to boil river or lake water.