This doesn't apply to me yet, but soon. It is for all of us with a food sealer. My apologies if this has been posted; it's so blindingly obvious that it probably has been.

Convert 32 ounces of potable, boiled water to ice cubes. Add some bleach to it if you really want.

While the water is freezing, create a pouch suitable for 50 or so ounces of water from your heaviest sealing film. If possible with your sealer, double seal all your edges.

Put the ice cubes into the pouch and vacuum seal it. Double seal the open end if possible with your sealer.

Label properly. That includes marking the 32oz mark when the water thaws with bag held upright so it can be reused as a water container in an emergency, with a marked capacity for purification purposes.

If double sealing the edges is not possible, possibly double bag? Or possibly store several in a second outer bag, mylar or opaque if possible.

Store these in an opaque, sturdy container, along with a small package of binder clips (so that you can roll and crimp the opening if you don't need the whole thing or are reusing it) and possible a safety envelope cutter.

They should be good for at least a year, and lot cheaper than the aquapouches. No light, no air, a lot of germs are out of luck and if you use freshly boiled water everything should be dead. (If you wanted to be really sure, we could test the reliability after boiling of the material by boiling the pouches for say 10 minutes in a pressure cooker THEN storing them.) And we wouldn't have to worry about them rupturing when freezing because it was a comfortably oversized pouch to begin with, unlike supermarket bottled water.

I know that double bagging would be a lot of packaging, but it could be used for cooking later, and it is better to open your water container and find water in pouches rather than pouches in a puddle. Or just a puddle. That, and it makes distributing it if needed easier- one package equals a gallon (one day's conservative ration), with four bags (a quart is pretty easy to manage) if you have to break it up further for cooking or packing. I see this as something where you could probably pack 72 hours of water and food (conservative levels) in a 5-gallon pail along with some odds and ends (matches, batteries, meds, socks, maybe ethanol stove fuel, et al) so you can distribute it easily for a multi-car bug out.

Or did I just reinvent the wheel?