Flood safety: the NDMA do's and don'ts, in order of when you need them

The National Disaster Management Authority sits under the Ministry of Home Affairs and publishes flood guidance free to the public. It is organised by when, not by topic, which is the right way round — during a flood you do not have time to search a list.

Before a flood

Structural work you do while the weather is fine. Elevate the furnace, water heater and electric panel if they sit where water reaches. Install check valves in sewer traps so floodwater cannot back up into the house. Avoid building in flood-prone land unless the structure is elevated and reinforced.

When flooding is likely

Keep the radio or television on for information. Bring in outdoor furniture and move essential items to an upper floor. Make sure every family member carries an identity card, and put valuables high in the house.

Flash floods build fastest in streams, drainage channels and similar channels — if you are near one, treat the warning as immediate.

Preparing to evacuate

Secure the house and turn off utilities safely.

During evacuation

Two rules do most of the work here:

• Do not walk through moving water. Six inches of moving water is enough to knock you off your feet. If you must walk through water, choose where it is still, and use a stick to test the firmness of the ground ahead of you.
• Do not drive into a flooded area. If water rises around the car, abandon it and move to higher ground if you can do so safely.

After the water goes down

Drink only chlorinated or boiled water. Avoid contact with floodwater — it may carry sewage, oil or chemicals.

The full page is short and worth reading start to finish before the season, not during it.