Stackable 7-gallon water container

What it is

A rigid, food-grade plastic container in the five to seven gallon range with a spigot, built to be filled at the tap and stored. The common shape is a squared-off jug that stacks two or three high on a shelf. Several brands make one; the shape matters more than the name.

Why it is first

Water is the first thing gone from every store and the one supply with no substitute. Bottled water is the easiest start, but it is bulky, it costs more per gallon, and the thin bottles degrade in a hot garage. A few seven-gallon jugs cover a family for the three-day window in less space than three cases of bottles, and you refill them for free.

Seven gallons is about 58 pounds full. That is the trade-off: it is the limit of what most adults can carry a short distance, which is why the portability score is a 3. If anyone in the house cannot lift that, buy the five-gallon size or two smaller ones.

What to look for

• A spigot that does not weep. Look for a vented cap and a spigot you can replace; the cheapest ones drip after a season.
• Square or rectangular, so it stacks and does not roll.
• Opaque or dark blue plastic. Light grows algae in clear containers.
• Food-grade, labeled as such. A fuel can shape in a different color is not the same thing.
• A size you can carry when it is full.

How to use it

Rinse it, fill it from the tap, cap it and date it with tape. Tap water from a treated city supply keeps for about six months without additives; swap it into the garden or the washing machine when the clocks change and refill. If you want longer storage, the EPA's guidance on treating water with unscented household bleach applies.

Keep it off bare concrete on a shelf or a board, out of direct sun, somewhere you could reach it with the power out.

Skip it if

You live in a small apartment with no closet space and no car. Two cases of bottled water under a bed do the same job for a single person, and the 72-hour kit guide covers the amounts.

Sources

• Ready.gov: Water
• EPA: Emergency disinfection of drinking water