It turns out my family uses closer to 20 gallons/ day. I now have to figure out a way to store at least 2-55 gallon barrels of water. My prior solution is a dozen 5 gallon paint cans (food grade) in the garage.

I took a lesson from my water heater- it maintains somewhere between 20 and 60 gallons of circulated water- always fresh. So to store [fresh] water, one needs a container of sufficient size and a mechanism to circulate that water. I have a poly tank with a city water pressure input and a garden watering valve output, with timer, that waters my garden daily- or, 500 gallons of circulated water. Said tank is insulated against freezing.

All I need do is stop input/output to preserve the water for emergency use.
-carl
_________________________
You are not out of options until you quit.