Do you know what to do in the event of a flood? Find out what you need to know, how to prepare, what to do when it happens and also what to do after the event.

Floods are New Zealand’s number one hazard in terms of frequency, losses and declared civil defence emergencies. Floods can cause injury and loss of life, damage to property and infrastructure, loss of stock, communities to become isolated, and contamination of water and land.

Floods are usually caused by continuous heavy rain or thunderstorms but can also result from tsunami and coastal storm inundation. A flood becomes dangerous if:

  • the water is very deep or travelling very fast.
  • the flood waters have risen very quickly.
  • the floodwater contains debris, such as trees and sheets of corrugated iron.
Pro Tip!

It is critical that communities understand their flood risk.

Contact your local council to find out if your home or business is at risk of flooding or visit BayHazards and view your local flood maps. If your property is located near a stream, river or drain, in a low lying/wetland area or on the coast, you may be vulnerable to flooding.

Getting ready before a flood strikes will help reduce damage to your home, business and help you survive.

  • Develop an emergency plan for your household or business.
  • If you are a farmer or have a lifestyle block, consider how and where you will relocate stock should the need arise.
  • Prepare a getaway kit (in case you have to leave home in a hurry).
  • Make sure you have the appropriate household and contents insurance and keep those details handy.
  • Stay informed. Severe weather events usually provide some time for warning and for you to take some preparedness actions. 
  • If you live in a flood prone area, consider storing sandbags to protect your home should the need arise.

Flooding in River Catchment Areas
Heavy rain can cause rivers and streams to rise rapidly. Never assume that you are safe close to a river, stream, drain or other type of waterway during a flood. Assess the risks if you need to be close to a waterway during a flood event. The water may overtop banks or erosion could cause the ground around waterways to give way. Debris can also build up blocking waterways and creating dams which have potential to suddenly release a large volume of water. This happens more often than you might think. Be aware of your surroundings, don’t take unnecessary risk and let someone know where you are at all times.

Stopbanks provide some remedial protection from flooding however, if there has been a significant period of rainfall this can increase the risk of overtopping or breaching. If you and your family feel at risk, leave immediately and contact the local council.

Coastal Inundation
If you are by the coast or at the beach, remember to think about storm surge. It can be particularly dangerous around river mouths and low-lying areas. Don’t get cut off.

Stormwater Systems
Flash flooding can overwhelm the stormwater system and cause surface flooding. Consider storing sandbags if you live in a flood prone area (you can contact your local council for more information on where to get bags). Move items of value higher from the ground and making sure your drains and gutters are clear. Utilities such as power and water supply may also be impacted.

  • Listen to your local radio stations as emergency management officials will be broadcasting the most appropriate advice for your community and situation.
  • If you have a disability or need support, make contact with your support network.
  • Put your household emergency plan into action and check your getaway kit. Be prepared to evacuate quickly if it becomes necessary.
  • Where possible, move pets inside or to a safe place, and move stock to higher ground.
  • Consider using sandbags to keep water away from your home.
  • Lift valuable household items and chemicals as high above the floor as possible.
  • Fill bathtubs, sinks and storage containers with clean water in case water becomes contaminated.
  • Turn off utilities if told to do so by authorities as it can help prevent damage to your home or community. Unplug small appliances to avoid damage from power surges.
  • Avoid contact with flood water whenever possible. Floodwaters can carry bugs that cause disease from the ground surface, septic tanks and sewerage systems.
  • Do not attempt to drive or walk through floodwaters unless it is absolutely essential.

Flood waters can take some time to recede, and it is important that you stay informed so that you, your family, and your home can stay safe.

After a flood there may be extensive damage to your property and your day-to-day life may be quite disrupted. Here are some simple reminders of what you should and shouldn’t do after a flood:

  • It may not be safe to return home even when the floodwaters have receded. Continue to listen to your local radio station and adhere to the advice and instructions authorities provide. 
  • Help others if you can, especially people who may require special assistance. Consider family, friends and neighbours who may be vulnerable.
  • It is important to make sure your food and water aren't contaminated. Throw away food (including canned goods) and water that may have been contaminated by floodwater.
  • Avoid drinking or preparing food with tap water until you are certain it is not contaminated. If in doubt, check with your local council or public health unit.
  • Look for and report broken utility lines to appropriate authorities and suppliers.
  • Keep your pets and livestock safe. Check on them regularly and consider their welfare.
  • If your property and/or contents is damaged, take notes and photographs and contact your insurance provider as soon as possible. If you rent your property, contact your landlord and let them know about the damage. and your contents insurance company as soon as possible.
Pro Tip!

Let the council know if you see water coming from anywhere unusual and consider taking a photo or video.

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