Over 80 per cent of Australians live on our coasts. We’re a country of sun-kissed beach lovers. But did you know that 60% of our homes (over 700,000 residences) are within 3 kilometres of the Aussie shoreline? The same 60% of homes are built on land less than 5 metres above sea-level. If that’s you, then it’s likely you’re in a tsunami danger zone. But do you even know how to survive a tsunami if one hits? In this post you’ll find the answers, direct from the people who know – The Australian Surf Lifesavers and Bureau of Meteorology.

So what are you waiting for? Let’s find out how to survive a tsunami – in the water, at the beach, or at home – down under.

How to survive a tsunami

In this post we’re going to run through 6 things that you can do today, to help you survive a future tsunami. While specific to Australia, these tsunami safety lessons apply most everywhere:

1. Know about tsunamis, especially the early warning signs.
2. Know what to do when a tsunami warning is issued.
3. Listen for updates from Australia’s Tsunami Warning Centre – on radio, TV, social media.
4. If you live within 1km of the coastline, prepare a Tsunami Emergency Kit and have an action plan.
5. Follow the advice of emergency services before and after.
6. Follow the expert advice (below) on what to do during a tsunami, based on whether you’re in the water, on the beach or at home.

Let’s look first at what you need to know, to successfully survive a tsunami here.

What to know, to survive a tsunami in Australia

Here are 9 quick facts you should know about tsunamis, to understand how they might impact you:

1. Tsunamis are typically caused by underwater earthquakes. Volcanoes, underwater landslides and meteors can also cause tsunamis.
2. Any earthquake above a magnitude 6.5 can potentially cause a tsunami.
3. 80% of the worlds earthquakes – and most of the world’s tsunamis – occur in the Pacific Ocean.
4. The Indian Ocean has the second most tsunamis, after the Pacific.
5. Tsunamis can travel thousands of kilometres across an ocean. The waves can be kilometres long.
6. A tsunami can move across a water body as fast as a jet plan. That’s 600 – 900km per hour.
7. It would take a minimum of 2 hours for a tsunami to reach Australia from the nearest underwater earthquake hotspots nearby.
8. Tsunamis can have multiple waves, so even if the first one has passed, another could be right behind it.

Thankfully, Australia has a Tsunami early warning system to alert the community if there is a risk.

The Joint Australian Tsunami Warning Centre (JATWC), run by the BOM and Geoscience Australia, sends out tsunami alerts and warnings to the media when tsunami risks are triggered. Warnings will be on the telly, the radio, social media and on the BOM website.

This is what a tsunami warning map looks like from the JATWC:

The warnings to watch out for if you’re on the coast are:

• Watch: a tsunami may occur = pay attention to alerts.
• Marine warning: a marine is for dangerous waves, potentially hitting the local foreshore = get out of the water.
• Land warning: a land warning is for coastal inundation in low lying areas = get to higher ground.

What is Australia’s tsunami risk?

According to the BOM, a tsunami could hit some areas of the Australian coast with waves of up to 10m above sea level.

If the surrounding land area is less than 10m above sea level, the wave could travel inland up to 1km.

This modelling is going to inform what to do, and how to survive a tsunami down under.

Remember: 10 meters high. 1 kilometre inland.

What are tsunami warning signs

In Australia we’re lucky enough to have a tsunami warning system. But it’s still important to know the early warning signs (in nature) if you want to know how to survive a tsunami. You may be in an isolated part of the coast, or overseas – without the luxury of an official warning.

Here are the 4 signs to look out for:

1. If you’re near the shore and you feel the ground shake. It might be an underwater earthquake that could cause a tsunami.
2. If you see the ocean water drain quickly from the beach, that could be a sign of a tsunami. If the water pulls back or the tide disappears and that seems weird to you, don’t head down to take a look. Instead head away from the water.
   • Water doesn’t not always recede before a tsunami, so don’t rely on this sign.
3. Another signal of a tsunami is if you hear a loud roaring or whistling sound from the ocean.
4. Or if you see a wall of white water or waves on the horizon. It may just be a tsunami headed your way.

The most important thing to do if you spot the signs is take action straight away.

Even if you’re not sure. Trust your instincts and listen to your intuition. And definitely don’t wait for a warning. It may not come in time.

Next, let’s look at what action to take when a tsunami hits.

How to survive a tsunami in the water

If you are caught in the water when a tsunami hits, the water will quickly become frothy and murky. It will throw you about with its power and may drag you under. It will quickly become littered with dangerous debris that can easily injure you.

So what chance do you have to survive?

Can you survive a tsunami underwater?

The answer is yes. Here is how to survive a tsunami if you are in the water:

It’s likely with the force of the waves that you’ll find yourself disoriented and under water. Your first instinct is is fight to get your head to the surface.

The waves come in.. well, waves. So your best chance to surface is between each wave.

Once you have your head out of the wash, try to spot and grab on to something that floats. A tree branch for example. Even better, grab onto something anchored to the ground like a tree trunk if you can.

Hold on like your life depends on it.

If you are floating in the wash, try to lie flat. You don’t want your feet to catch in debris and drag you under.

Don’t fight against the wave. Doing so will burn your energy fast. Go with the wave at first.

When the waves subside a enough, swim for safety. Swim towards higher ground or a concrete or brick building. Something that you can climb up onto, clear of the water.

If you do hear a tsunami warning before one hits, leave the water as quickly as possible and move far away from the ocean’s edge. You may get caught in the dangerous rips and currents, which could drag you out to sea. Even if the waves look small, the power of them could be enough to roll you under.

Follow the steps below on ‘How to survive a Tsunami on the beach’ (below).

How to survive a tsunami at the beach

In 2006, a tsunami that started in Indonesia hit WA’s coast at Steep Point. Waves travelled 200 meters inland. The tsunami washed away camp sites with enough force to carry away a four wheel drive vehicle.

What would you do, in this situation?

Aussies are avid campers and beach lovers, so it’s important we all have a little knowledge about how to get through a tsunami at the beach.

If there is a tsunami warning, move immediately to higher ground. Remember that 10m wave height BOM prediction? You should aim to go somewhere at least 10 m above sea level.

Tsunami prone areas will have a tsunami evacuation zone at the beach. If you see signs like these around as you go, follow them:

If you are in a flat, low lying area with no higher ground, move at least 1 km inland away from the ocean.

10 meters high. 1km inland.

If the land is dead flat around and you can see the waves on the horizon or other early warning signs, you could be out of time get 1km away.

If so, head up – as high as you can go.

The safest place to shelter is at the top of a brick or concrete multi-storey building. Move to at least the 3rd floor or above.

Once you’re safe, stay there until you hear from official sources (like the BOM or JATWC) that the risk has passed and it’s safe to return. There could be more waves coming…

Surviving a tsunami in a house

In the Fukushima earthquake in 2011, waves from the tsunami washed as far as 8km inland from the sea. The highest waves hit 40m above sea level at the shoreline, washing away entire homes.

But what do you do when a tsunami threatens your home?

You evacuate.

If you’re well prepared, you already have a Tsunami Emergency Kit (or Emergency Go Bag) and action plan. Congratulations, you’re already a step ahead!

Your tsunami action plan should map out your evacuation route to higher ground or inland. With limited time to move, it’s best to be clear beforehand where that high ground is.

Your action plan should also tell you when to evacuate (what stage of the warning system) and who to contact.

When the time comes, grab your Emergency Go Bag or Tsunami Emergency Kit, and follow the evacuation route in your action plan.

Some countries have marked tsunami evacuation routes. Follow these.

Once you reach your destination, tune in to your emergency radio (from your Tsunami Emergency Kit) to get updates, if available. Do not return home until authorities have given the ‘all clear’.

Your action plan should also step out what you will do if there is no time to evacuate.

Move to the highest point possible in your home. Don’t go into the attic however, as you may become trapped. Grab your Tsunami Emergency Kit and move on to the rooftop, if possible.

Activate your personal locator beacon or call the SES.

Wait for help to arrive or the danger to pass. Do not leave your rooftop until you hear from the authorities that the tsunami has passed.

Once the tsunami has passed, there will likely be widespread damage and flooding. Be careful of downed power lines and gas leaks. Stay away from buildings or structures that could collapse.

What NOT to do in a tsunami

Sometimes our actions can get us into more trouble, if they’re not informed or well thought out. Here’s what NOT to do, if you’re faced with an impending tsunami:

1. If the sea recedes, don’t follow it to investigate. Run in the opposite direction.
2. Don’t just run inland. The answer to the much asked question of ‘Can you outrun a tsunami?’ is NO.
3. Do not stay in your car if there is a tsunami warning. You may become trapped. Head to higher ground on foot.
4. Do not return to the tsunami zone after the first wave. There may be multiple waves, higher than the first.
5. A tsunami is not spectator sport. Don’t head to the coast to watch one!
6. Do not be complacent. While tsunami threats are rare, they can quickly become deadly. Treat warnings seriously.

Conclusion

Being prepared is about being aware of what you might experience before the danger occurs. We hope this post has helped inform you about what to expect from and how to survive a Tsunami in Australia. We’ve rounded up the expert views from BOM and the Australian Surf Lifesavers. The consensus is, If you live on the east or west coast within 1km of the shoreline, it’s important to be prepared for a tsunami. Make sure you have an action plan and Tsunami Emergency Kit ready. Know what you will do in a tsunami warning. Follow the expert-recommended steps during a tsunami to improve your chances of survival.