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Sounding the alarm - Christchurch tsunami sirens to be tested

Joe Shaw
Sumner Beach Joe Shaw 050424
Sumner Beach.   JOE SHAW // NZBS

Forty-five tsunami alarms will go off between Brooklands and Taylor’s Mistake at 11am this Sunday.

While they will be heard for roughly three minutes, Christchurch City Council Civil Defense and Emergency Management Manager Brenden Winder says there’s nothing to be alarmed about. 

If you are near the coast on Sunday morning and hear the sirens going off, you don’t need to evacuate or be alarmed.

"This is just a test to make sure the system is working.” 

It comes as a yearly tradition, where the alarms are tested at both the beginning and end of every daylight savings period. 

And just in case anybody is not aware it’s a test, nearby residents will be able to hear 'this is a test of the tsunami warning sirens. Do not be alarmed. This is only a test’.

The system is designed to trigger a warning in advance, up to three hours before a tsunami can even reach the coastline. 

Environment Canterbury (ECan) says the Canterbury region has previously experienced four damaging tsunamis in the past: in 1868, 1877, 1960 and 2010, all out of the South American coast. 

Modelling by ECan shows a locally sourced tsunami could take an hour to reach the shore, which would mainly be caused by earthquake fault lines both on land and under the sea off the North Canterbury coast.

The alarms have been previously criticised over the past few years, including during the 2016 Kaikoura earthquake, when the alarms went off at 2am, despite a Ministry of Civil Defence tsunami alert being announced an hour prior. 

In 2020, it was found the 45 alarms installed between 2012 to 2014 weren't meeting the noise level set by the National Emergency Management Agency’s (NEMA’s) Technical Standard. 

Even with the alarms, any imminent tsunami would still be alerted to residents through both the Civil Defence and New Zealand Police channels, including the sirens, television, radio, social media and community groups. 

Winder notes now is a good time to take stock.

"While this weekend’s siren testing is routine, it’s also an ideal time to make sure you and your family have an evacuation plan and have all your essential supplies ready."

Click here to find out the Christchurch City Council’s map of tsunami evacuation zones.