How Much Water and Food Do You Need for a 2-Week or 30-Day Power Outage?

Three days is the minimum every agency agrees on. It's not what a long outage takes. When the power stays off for a week or two, the water can stop too: during Oklahoma's 2007 ice storm some city water plants couldn't pump for a short time, and during the February 2021 Texas freeze about 7 million people were told to boil their water. The time to store it is before.

How much water to store

The standard is 1 gallon per person per day: about a half gallon to drink (FEMA and the Red Cross say a normally active person needs at least that much) and the rest for cooking and basic hygiene. Store more for hot weather, pregnancy, anyone who is sick, and pets (CDC).

What that looks like: a gallon of water weighs about 8.3 pounds. A family of four's 2-week supply is 56 gallons, roughly 470 pounds: about a dozen 5-gallon containers, or 56 store-bought gallon jugs. That's a closet floor, not a pantry shelf. Plan the space.

How to store it

• Store-bought, sealed water is the simplest. CDC calls unopened, commercially bottled water the safest and most reliable source in an emergency.
• Filling your own? Use food-grade water containers, never ones that held chemicals like bleach or pesticides, and replace the water every six months (CDC).
• Keep it somewhere cool and dark, off concrete if you can, and away from gasoline, paint and cleaners.

Water already in your house

FEMA and the Red Cross list three safe sources most people forget: the water heater tank, the pipes and ice cubes. Shut off power or gas to the water heater before you drain it. To use the pipes, open the highest faucet in the house to let air in, then drain from the lowest one.

When stored water runs low

• Never ration water. Drink what you need today and find more tomorrow (FEMA and Red Cross).
• Boil clear water at a rolling boil for 1 minute (EPA), if you have a safe way to heat it outdoors.
• Bleach: 8 drops of 6% unscented household bleach (or 6 drops of 8.25%) per gallon, stir, wait 30 minutes (EPA).
• Filter straws handle fresh water sources as a backup; they don't remove viruses or chemicals. See filter straws vs. tablets.
• Watch for city water distribution sites and boil-water notices from your water utility.

How much food to store

Plan on about 2,000 calories per adult per day. Children need less food, but people working in the cold burn more, so use 2,000 for everyone and the extra becomes your margin. FEMA's food and water guidance says to eat at least one well-balanced meal each day and drink enough water for your body to use the food.

How to count your pantry in calories

Every food label tells you: calories per serving × servings per container = calories in that can, jar or box. Add it up shelf by shelf with a pencil. Most families find they have a few days of food, not two weeks, because so much of it is in the fridge and freezer.

What to store

• Food you already eat, so you rotate it instead of throwing it out: put new items in back, older ones in front (FEMA)
• No-cook protein: canned tuna, chicken, chili, beans, peanut butter
• Calorie-dense staples: nuts, trail mix, granola and food bars, crackers, dried fruit
• Canned fruit and vegetables (the liquid counts toward your water)
• Comfort food and drink mixes: they matter more in week two than you'd think
• Baby formula and food, special diets, and pet food
• A manual can opener, and a camp stove or grill used outdoors only

Keep it in a dry, cool, dark spot (FEMA). Skip foods that make you thirsty, like very salty snacks, unless you've stored extra water.

Eat in this order

1. The fridge, while it's still cold: about 4 hours with the door closed (FoodSafety.gov).
2. The freezer: a full one holds about 48 hours, a half-full one about 24 (FoodSafety.gov). Thawed food that still has ice crystals or is at 40°F or below can be refrozen.
3. The pantry. Never taste food to decide if it's safe; when in doubt, throw it out.

Where emergency rations fit

Sealed ration bars like the Datrex 3,600-calorie pack keep about five years (per the maker) and need no cooking, which makes them right for a go-bag and the car. For two weeks at home they're not the plan: one adult would need about eight packs for 28,000 calories, and pantry food you already eat is cheaper and easier to live on. Use rations as the backup layer.

Medicine: the supply people forget

• The Red Cross kit list calls for at least a 7-day supply of medicines. For a two-week plan, ask your doctor and pharmacist about keeping a longer supply.
• Ask how long each medicine keeps at room temperature, and get a plan for anything that's critical for life (Ready.gov).
• If the power is out more than a day, Ready.gov says to discard medicine that needs refrigeration unless the label says otherwise and get a new supply.
• Insulin: FDA says vials and pens may be kept unrefrigerated between 59°F and 86°F for up to 28 days. Keep it out of direct heat and sunlight, and never use insulin that has frozen.

Do the math for your house

Our free printable checklist has a water and food calculator for your household. For the rest of the long-outage plan, read the week-by-week guide and how to stay warm without power.

Backups we sell (and what they aren't)

We don't sell bulk water or a 30-day food supply. Your grocery store does that better and cheaper. What we sell is the carry-out and backup layer: sealed water pouches, rations and filter straws.

Sources

1. CDC: How to Create an Emergency Water Supply
2. American Red Cross: Be Red Cross Ready (PDF)
3. FEMA and American Red Cross: Food and Water in an Emergency (archived copy)
4. Ready.gov: Build a Kit
5. EPA: Emergency Disinfection of Drinking Water
6. FoodSafety.gov: Three Ways to Keep Food Safe When You Lose Power
7. Ready.gov: Power Outages (archived December 2020 copy, includes medicine guidance)
8. FDA: Insulin Storage and Switching Between Products in an Emergency
9. NWS Norman: The December 8-11, 2007 Ice Storm in Oklahoma
10. NPR: Millions in Texas Under Boil-Water Notices Because of Winter Storm (Feb. 17, 2021)