Stockpile Quantities Explained

The official baseline: at least 3 days, ideally 1 week

Japan has a clear public standard for household stockpiles: the Cabinet Office's disaster-preparedness office recommends at least 3 days, ideally one week of water and food. The 3-day figure reflects the reality that rescue operations take priority right after a disaster, and relief supplies take time to reach everyone. For wide-area disasters like a Nankai Trough earthquake, a week or more is considered desirable.

Converting days into actual amounts is simple arithmetic: people × days × daily amount. Here it is by category.

Water: 3 liters per person per day

Covering both drinking and cooking, 3 liters per person per day is the figure used across official materials. In practice:

• 1 person × 1 week = about 21 L (roughly 11 two-liter bottles)
• 2 people × 1 week = about 42 L (roughly 21 bottles)
• 4 people × 1 week = about 84 L (roughly 42 bottles - about 7 cases)

A family of four needs around seven cases for a week, which makes storage the real challenge. Combine the distributed-storage approach below with a separate plan for utility water (toilet, washing) such as leftover bathwater. Long-life water by the case

Food: count in meals, 3 per person per day

Food is easiest to manage counted as meals: one person's week is 21 meals; a family of four needs 84. The key point is not to fill that count with specialty emergency food alone.

• Staples: rice, packed rice, dried noodles, alpha rice in combination
• Mains: canned food, retort meals and freeze-dried dishes across different flavor families
• Extras: vegetable juice, canned fruit and snacks for nutrition and morale

Anchoring this in the rolling stock method - simply keeping more of what you already eat - makes even a week's stock sustainable. The Home Stockpile Checklist calculates the specifics from your household size and duration.

How to think about one month

A month sounds unrealistic until you reframe it: not "buy a month of emergency food" but "run a deeper pantry." A 10 kg bag of rice, a stock of dried noodles, cases of canned and retort food, spare seasonings - a thicker everyday inventory covers most of a month's staples and mains on its own.

The usual gaps are water and gas canisters. Build water up over several case purchases, and stock canisters generously based on how much you expect to cook - burn times are on the product label.

Storage: never in one place

Spread your stockpile across the kitchen, closets, each room and the car. Concentrated in one spot, it can all become unreachable at once. Under-bed space and furniture gaps are perfectly good storage.

Boxes with a contents-and-expiry note taped outside make reviews dramatically easier. Storage boxes

In flood-prone areas, store on the second floor or higher rather than the ground floor - check your municipality's hazard map for local risk.