The Church of Jesus Christ of Latter-Day Saints recommends keeping three-month supplies of water and non-perishable foods that are part of families' typical diets. The church recommends storing them in a cool, dry place along with other food staples that have longer shelf lives. Store water in secure containers in areas away from heat and sunlight.
The church recommends gradually building a three-month supply by first estimating the amount of food the family eats in a day and then multiplying that amount by seven to get a week's supply. From there, grow the storage to a month’s supply and then up to three months. Once you have an established three-month emergency supply, add items such as wheat, rice, oats, dry pasta and beans with shelf lives of 30 years or more. As you rotate through the three-month supply, incorporate some of the long-term storage items to round out meals.
Purchase pre-packaged bottled water or recycle other containers such as used juice and soda bottles. Only use food-grade containers and avoid containers that do not contain polyethylene terephthalate plastic. Containers with this plastic typically have labels of "PETE" or "PET." Clean any water storage containers before using with a mixture of 1 teaspoon bleach and 1 quart of water.