Tsunami evacuation zones and routes : Christchurch City Council

Find out if and when you need to evacuate.

Long or strong, get gone

If you feel a rolling-motion earthquake for longer than a minute or a strong earthquake that makes it hard to stand up, then you need to get gone.

When to evacuate

Your best warnings for a tsunami are:

a long rolling-motion earthquake that’s longer than a minute,
a strong earthquake that makes it hard to stand up, or
unusual ocean behaviour: loud or strange noises coming from the sea (e.g. like a jet plane or train) or sudden sea level changes.

You need to evacuate the red and the orange evacuation zones if you experience or observe these warning signs.

It is unlikely that a tsunami has been created, but it is better to be safe than sorry. Tsunami waves come in series. The first wave may not be the biggest, so you need to be prepared to stay out of the evacuation zones for many hours. If a tsunami is coming from close to our shore, there will not be any time to issue an official warning, sound sirens or to send an emergency mobile alert. The earthquake is your best warning.

An official tsunami warning can be issued for a tsunami coming from outside the Canterbury region or from across the Pacific Ocean. You will hear Civil Defence official tsunami warnings on the radio, on television, on social media, or via an Emergency Mobile Alert, telling you which zones to evacuate.

What is a long or strong earthquake?

A long earthquake is an earthquake that shakes for longer than one minute.

The bigger the earthquake magnitude, the longer the shaking. So if the earthquake lasts for longer than a minute, you know that it is big, somewhere, probably over magnitude 7.5 which is big enough to possibly create a damaging tsunami if it was under the ocean.

A strong earthquake is when the shaking is so strong that it is hard to stand up – the sort of earthquake where furniture starts moving around and things fall over.

Why the long or strong message?

If you are near a big earthquake, the shaking will be long and strong. A big earthquake further away from you may be felt as a long but mild or moderate, rolling earthquake.

A big earthquake far away may still have created a tsunami, it will just take longer to reach you than if it was just offshore. So this is why the message is long or strong, rather than long and strong.

Sirens and when to return home

The sirens will be activated for a tsunami with more than three hours of warning time, and if time allows, the sirens may be sounded for a tsunami with one to three hours of warning time.

Sirens installed along the Christchurch coastline are intended to warn you about a tsunami generated in the Pacific Islands or across the Pacific Ocean, and if there is time, for a tsunami generated further afield from Canterbury i.e. in the North Island's east coast.

Sirens are not intended to warn you about a tsunami created close to our shore. A long or strong earthquake will be your only warning of a tsunami created close to our shore.

Safe to return, 'all clear' messages will be broadcasted by Civil Defence using radio, TV, radio, Council's Newsline(external link), and social media.

You can also do your bit by sharing official warnings with friends and family in the evacuation zones.

Emergency Mobile Alerts

Emergency Mobile Alerts are messages broadcasted by authorised agencies to keep people safe. The alerts can be targeted to areas affected by serious hazards, including tsunami. If your phone is on, capable and inside the targeted location, you should get the alerts.

It is important that you still evacuate after a long or strong earthquake and not wait. Emergency Mobile Alerts are just one way of finding out about serious threats, so ensure you have an emergency plan and know where to find more information during an emergency.

Emergency Mobile Alerts will only be used for serious hazards that involve threats to life, health or property, or in some cases for test purposes. If your phone is on, capable and inside the targeted location, you should get the alerts. You don’t have to download an app or subscribe to a service, just ensure your phone is capable and updated.

Visit the Civil Defence website to find out if your phone is ready to receive Emergency Mobile Alerts and access Emergency Mobile Alert factsheets(external link)

Tips to evacuate safely

Residents and businesses in the tsunami evacuations zones should have plans in place for an evacuation.

Plan your route

Know what to do and where to go. Understand your evacuation zones so that you know which zones you may need to evacuate. Are there any local landmarks in your area to indicate that you’re out of the evacuation zones? Take some time today to make a plan with your family. Do you know the evacuation route that is closest to your home or workplace?

Carpool

If possible, take extra passengers in your car. Check whether your neighbour needs a ride or help evacuating. Carpooling reduces the number of cars on the road and helps with traffic flow.

If you are driving, it is best to go further than the edge of the zone, to make room for those coming behind.

Cycle or walking routes

Sometimes evacuating on foot or bike is faster to get out of the evacuation zones because the roads can get congested easily. Look at possible walking or cycle routes near your home. Why not take the time to go for a walk and plan your walk/bike route that suits your family.

Talk to friends and family

If you need to evacuate, it’s more comfortable to go to a friends or a relative’s place who are away from the evacuation zone(s) until the “all clear” has been given by Civil Defence. Get to know any friends and family living away from the evacuation zone(s). Talk to them about you or your family visiting them during an evacuation.

Secure your home

Secure your home as you normally would when leaving for an extended period. Make sure to lock your doors and shut windows securely, and if you can, switch off any utilities like gas.

Emergency bag

A tsunami warning may be in place for many hours, because the first wave is often not the biggest. You may be out of the evacuation zone for some time, which is why you need an emergency bag. Pack anything you may urgently need and can carry. This can be personal items (e.g. medicine, glasses, and sanitary items), supplies for babies and pets, water bottle, snacks, and family documents (e.g. copy of driver licences). Make it a family discussion on what needs to go on the emergency bag for your family. Do you know where your emergency bag is kept to grab it quickly?

Check out happens.nz for what should be in your kit(external link)

Don’t forget your pets

If you are able to, take your pets with you when you evacuate. They are your responsibility. Include what your pets may need, such as pet food, in your emergency bag.

Rock falls

Be aware that if the ground shaking is strong, there may be unstable cliffs and rock falls.

Do not climb up onto the roof of a building. The chances of going onto the roof and falling off, especially with young children, are much higher than the chances that a damaging tsunami has been generated.

Schools and early childhood centres

Schools and early childhood centres are required to have plans detailing their response to emergency events. Ask at your school or early childhood centre what arrangements they have in place and the steps you are expected to make to collect your child (or children) following an evacuation.

Rest homes and retirement villages

Rest homes or retirement village staff may evacuate occupants to pre-arranged safe assembly areas outside the evacuation zone. The ‘pre-arranged’ safe assembly areas will be identified in the rest home's or retirement village's emergency plan.

Find out about the arrangements you are expected to make to contact your family members following an evacuation at a rest home or retirement village.

Primary tsunami evacuation routes

It is your responsibility to determine the best place for you and those with you to move to. Plan your evacuation route ahead of time with your family.

When you evacuate, take your emergency pack with you because a tsunami warning can be in place for several hours.

Primary tsunami evacuation routes are suggested driving routes by car to evacuate out of tsunami evacuation zones. For a tsunami with more than three hours of warning time (i.e. a distant source tsunami), traffic officials can assist where traffic congestion is likely to occur and an assisted evacuation may be needed.

Assisted evacuation will depend on things like road conditions (e.g. major road works), time of day (e.g. night time vs day time), season, and public holidays. It is likely there won't be enough time for an assisted evacuation when there is less 3 hours of warning time for a tsunami (i.e. local source tsunami).

Evacuation routes

If you are required to evacuate, below are the suggested primary evacuation routes to take. Depending on the warning time, assisted evacuation can be provided for routes that are likely to experience traffic congestion.

Harbour Road - Kainga Road - Marshlands Road (Kainga)
Lower Styx Road - Marshlands Road (Styx)
Beach Road - Mairehau Road (Northshore)
Bowhill Road - Travis Road (North New Brighton)
Hawke Street – Pages Road
Towards city from Wainoni Road
Bridge Street - Breezes Road (South New Brighton)
Bridge Street - Dyers Road - Linwood Avenue (Southshore)
Bridge Street - Dyers Road – Ruru Road (Southshore)
Rocking Horse Road - Estuary Road - Bridge St (Southshore)
Marine Parade - Bridge St (Southshore)
Main Road - Ferry Road (Redcliffs, Sumner)
Wakefield Avenue - Evans Pass Road - Summit Road (Sumner)
Ferry Road or Hargreaves Road (Ferrymead)
Bridle Path Road - Tunnel Road (Heathcote Valley)

Civil Defence Centres may be opened in an evacuation especially for orange and yellow tsunami evacuation zones. These will be set up as soon as possible and the locations will be publicly announced by Civil Defence.

Evacuation zones

If you feel a long or strong earthquake, you need to get gone. Find out if you are in a tsunami evacuation zone.

A tsunami evacuation zone is an area that you may need to evacuate from if you feel a long rolling earthquake that lasts more than a minute, or a strong earthquake that makes it hard to stand up, or if there is an official tsunami warning. You may be asked to stay out of the evacuation zones for many hours.

There are three tsunami evacuation zones for Christchurch City and Banks Peninsula.

Red Evacuation Zone

The red evacuation zone includes the estuary, rivers, beaches and harbours. You should evacuate this zone, if you feel a long or strong earthquake, or if you are advised to evacuate in an official tsunami warning. Even for a tsunami that won’t flood land, waves can still cause strong and unpredictable currents and surges that can be dangerous for people in or near the water.

Orange Evacuation Zone

The orange evacuation area includes low-lying areas nearest to the coastline. You should evacuate the orange zone if you feel a long or strong earthquake, or if you are advised to evacuate in an official tsunami warning. You can move into a yellow zone unless there is an official tsunami warning from Civil Defence to evacuate the yellow zone.

Yellow Evacuation Zone

You only need to evacuate this zone if you are advised to do so in an official tsunami warning. You do not need to evacuate this zone if you feel a long or strong earthquake, but you can always self evacuate for your own peace of mind.

What is the difference between the red and orange evacuation zones?

The red zone covers beach, estuary, harbour and river mouth areas – there are no houses in the red zone.

The orange zone covers the lowest lying land, including residential and commercial areas, nearest the sea.

The main reason for having these two separate zones is that even though most tsunamis will not flood land, they can still cause unpredictable currents and surges in the sea and on beaches. Therefore most official tsunami warnings issued by the Ministry of Civil Defence & Emergency Management will be 'Beach and Marine Threat' warnings, when you only need to stay out of the red zone – beaches, estuaries, harbours and river mouths.

Only occasionally will the Ministry of Civil Defence & Emergency Management issue a 'Land and Marine Threat' warning, in which case you will be told to either only evacuate the red and orange zones, or if it is a very large tsunami, to evacuate the red, orange and yellow zones.

After a long or strong earthquake it is possible (although unlikely) that a tsunami has been created that could inundate the lowest lying land nearest the sea in Christchurch and Banks Peninsula, which is why we advise leaving the red and orange zones if you feel a long or strong earthquake.

Please note that these zones were determined by hazard scientists and emergency managers, which reflect our best knowledge at December 2017. As research about earthquakes and tsunami risk continues, and further modelling work develops, it is possible that the zones could change slightly.

Evacuation zones map

Map Listing

If you feel a long (more than a minute) or strong (hard to stand up) earthquake you only need to move inland far enough so that you are no longer in the red or orange zones.

If you are not in a tsunami evacuation zone, you do not need to evacuate in a long or strong earthquake. You can expect people to travel into this zone from the coastal areas during a tsunami evacuation.

Please note that in other parts of New Zealand, you may need to evacuate all zones if you feel a long and strong earthquake because of higher local tsunami risk compared to Christchurch City and Banks Peninsula. You need to check your local arrangements if you are in a different part of New Zealand.

Types of tsunami

Tsunamis are created by underwater earthquakes, volcanic eruptions or landslides, and are made up of waves or surges lasting for several hours. Only the largest tsunamis flood land, most tsunamis are not big enough to flood land but can still cause strong and unpredictable currents and surges in the sea and river mouths.

The first tsunami wave may not be the largest and waves can arrive for hours. So a tsunami warning can be in place for many hours.

The source of a tsunami can be local, regional or distant, depending on where it originates and how long it takes to travel to our coast.

Type of tsunami	Risk to Christchurch City and Banks Peninsula	Warning time to evacuate
Local source tsunami (or near source tsunami)	There are no known local tsunami sources (off-shore earthquake faults or underwater landslides in Pegasus Bay or the Canterbury Bight) that could cause a damaging tsunami big enough to flood land along the Christchurch coast (Waimakariri River to Sumner) or Kaitorete/Birdlings Flat coast. There is a small possibility that an earthquake in Pegasus Bay or the Canterbury Bight could cause a tsunami that could flood some land at the heads of Banks Peninsula harbours and bays, because of the way these bays ‘funnel’ incoming waves. An earthquake that could cause a local source tsunami would be felt as a strong earthquake ( making it hard to stand up) in Christchurch and Banks Peninsula.	A local source tsunami takes less than 1 hour to reach the coast. It is unlikely there will be enough time to issue an official warning (including an Emergency Mobile Alert) for a local source tsunami. The earthquake is your warning.
Regional source tsunami	For Christchurch and Banks Peninsula this includes tsunamis generated by earthquakes off the Kaikōura coast, in Cook Strait, or off the eastern North Island coast. An earthquake that could cause a regional source tsunami would be felt as a long (longer than a minute) mild or moderate but long earthquake in Christchurch and Banks Peninsula. This sort of tsunami could flood low-lying areas of Christchurch and the heads of Banks Peninsula harbours and bays.	A regional source tsunami takes 1-3 hours to reach the coast. There may be time to issue an official warning for a regional source tsunami (including an Emergency Mobile Alert), depending on how far away it is created, but the earthquake is still your best warning.
Distant source tsunami	This type of tsunami is created by large earthquakes off the coast of southern New Zealand, in the Pacific Islands or across the Pacific Ocean, particularly South America. The most likely tsunami source for Christchurch is tsunami generated from South America. The earthquake would not be felt in Christchurch but there would be enough time to issue an official warning. In a worst-case scenario, this type of tsunami could flood significant areas of Christchurch.	A distant source tsunami takes more than 3 hours, and often more than 12 hours, to reach the coast. An earthquake across the Pacific Ocean would not be felt in Christchurch or Banks Peninsula. There will be time for an official warning from Civil Defence.

For more information on tsunamis visit the Environment Canterbury website.(external link)