If a disaster catches you without a stored supply of clean water, you can use the water in—

• your hot-water tank
• pipes and faucets
• ice cubes

If your tap water is safe to drink, so is the water in your pipes and hot-water tank, even if the idea seems unappealing. If you don’t drink tapwater, the water in your pipes and hot-water tank may still be useful for sanitation.

To use the water in your hot-water tank, be sure the electricity or gas is off, then open the drain at the bottom of the tank. Start the water flowing by turning off the water intake valve at the tank and turning on a hot-water faucet. Refill the tank before turning the gas or electricity back on. If the gas is turned off, only a professional can turn it back on.

To use the water in your pipes, identify and turn on the highest faucet in your home to let air into the plumbing. You then can get water from the lowest faucet.

If you need to find water outside your home, try

• Rainwater
• Streams, rivers, and other moving bodies of water
• Ponds and lakes
• Natural springs

Take steps to make water from any of these sources safer before drinking it. You should not drink flood water. Avoid water with floating material, an odor, or dark color. Use saltwater only if you distill it first.

• In a cool, dark place in your home, each vehicle, and your workplace.
• Preferably in store-bought, factory-sealed water containers.
• Alternately, in food-grade-quality containers made for storing water and available from sporting goods and surplus stores and other retailers. These containers must be thoroughly washed, sanitized, and rinsed. The water you store in them, if it’s from your tap, may need to be treated before being stored. Ask your public health service or water provider for information on whether and how to treat the water. Follow those instructions before storing any.

• Store-bought water past the expiration or “use by” date on the container.
• Containers that can’t be sealed tightly.
• Containers that can break, such as glass bottles.
• Containers that have ever held any toxic substance.
• Plastic milk bottles and cartons. They are difficult to clean and break down over time.

• Change stored water every six months.