One way to store water for long term needs is to purchase bottles and jugs of it that are commercially prepared, according to Ready.gov. Another way to store water for long term needs is to purchase food-grade containers and fill them.
If purchasing food-grade containers, users must wash them out with dish soap to clean them thoroughly, and then rinse them out with water again to remove the soap residue, notes Ready.gov. Anyone preparing water must not use milk or juice containers because they have proteins and sugars in them that cannot be removed, causing bacteria growth. Also, if a person prepares his own water for storage, he must replace it every 6 months.