No Garden, No River: Preparing for a Water Outage in a Flat or City Home

It's all very well to suggest a water purifier to use on collected rainwater or water from a river, lake, stream, pond, or swimming pool. But what if you live in a town or city? What if you don't have a garden with a pond or a water butt? A purifier is no use if you don't have a water supply to purify. So what should you do to secure your water resilience?

1. Start with a small supply of drinking water

Current UK government guidance recommends 3 litres of drinking water per person per day for three days. That means:

This is drinking water alone: allow extra for food preparation, hygiene, pets and individual medical needs. Be Ready

If you have limited space, build your supply gradually and split it between suitable locations: a cool cupboard, beneath a bed or the bottom of a wardrobe. Smaller bottles are easier to move and distribute than one large container.

Unopened commercially bottled water is a reliable starting point. Follow its storage instructions and expiry date. For water you bottle yourself, use clean, sanitised containers designed for drinking water; CDC guidance recommends replacing that water every six months. Never reuse containers that held cleaning products or other chemicals. CDC

2. Keep empty containers ready for a warning—or a collection point

Food-grade collapsible containers take up little space when empty. They can be filled if an interruption is announced, or used to collect water from an official distribution point.

• Choose containers with lids, handles, and an opening that is easy to clean.
• Keep drinking-water containers separate from cleaning buckets.
• Choose sizes you can carry upstairs: 10 litres of water weighs approximately 10kg, before the container.
• If you live in a flat or apartment, plan how you would collect water if lifts were unavailable.

Empty containers supplement an existing reserve; they won’t help if the taps stop without warning.

3. Filling the bathtub can help—but give it a specific job

If you have a bathtub, fill it while the taps are still working, to provide water for toilet flushing, rather than a drinking-water store. A bath is an open container and may contain cleaning-product or soap residues.

If there is advance warning, and the tap water remains safe to use:

• Fill drinking-water containers first.
• Then consider filling the bath for flushing, following any supplier instructions to conserve water.
• Keep children away from the filled bath.
• Only use it to flush if the drainage system is working normally; stop if there is sewage backing up.

A purpose-made, food-grade bathtub storage liner is another option for storing drinking water, used according to its instructions and filled while the supply is safe. It still depends on having warning and a working tap.

For homes without a bath, clearly labelled buckets or other containers can hold flushing water.

4. What to do when the electricity fails

A power cut does not automatically mean tap water is unsafe or about to stop. However, electricity failures can affect treatment and pumping, and water pressure may take time to recover after power returns. South East Water

1. Check the water supplier’s updates and any instructions about water quality or conserving supplies.
2. If the water is confirmed safe and still running, fill clean drinking-water containers as appropriate.
3. Prioritise drinking, food preparation and essential hygiene.
4. Check with neighbours and the building manager if only your flat or block is affected.

For flat dwellers, ask the managing agent in advance whether the building relies on electrically powered booster pumps, what backup arrangements exist and who to contact if they fail.

5. Reduce the amount of water you need

A few ordinary supplies can make stored water last longer:

• Ready-to-eat food that needs little water or washing up.
• Hand sanitiser and baby wipes for hygiene, kitchen wipes for general cleaning.
• A small washing bowl and a container with a dispensing tap.
• Some disposable plates so you don't need to do the washing up.

Thames Water includes alternatives to washing up and water-saving hygiene supplies in its preparation advice. Wipes should go in the bin. Keep some safe water available for handwashing; sanitiser does not replace it in every situation. Thames Water

6. Have a replacement-water plan

You should know your water supplier, keep its contact details offline and check where official replacement supplies will be available. People who need extra assistance can register for Priority Services beforehand; registration and delivery arrangements can take time. Thames Water

For someone on an upper floor, arranging help to carry water could be as important as buying equipment. Include a charged power bank and a plan to stay elsewhere if an extended outage makes essential care or sanitation difficult.

7. Where does a purifier fit?

Storage and purification do different jobs. Stored drinking water provides an immediate supply; a suitable purifier can help with certain alternative sources when its tested capabilities match the contamination risk.

Not any urban water source can be made safe. Floodwater, street runoff, ornamental fountains, and water containing fuel or chemicals are poor fallback choices. Boiling or disinfecting water does not make fuel or toxic chemical contamination safe, and you should never drink water from radiators or central-heating systems. CDC

A purifier doesn't necessarily mean you can disregard a supplier’s boil-water, do-not-drink, or do-not-use notice. Readers must follow the specific instructions issued for the incident, but it does mean you can store water quickly and purify it as you need it. Drinking Water Inspectorate.

You don’t need a garden to prepare for a water outage. A modest stored supply, suitable containers, and a practical collection plan can make a substantial difference.