Tsunami sirens along Christchurch’s coastline will be re-tested on Sunday 13 July, following an earlier failed attempt in March.

Forty five sirens, located between Brooklands and Taylors Mistake, will sound for up to three minutes at 11am on the final Sunday of the school holidays.

Residents will hear a warning tone followed by a spoken message: “This is a test of the tsunami warning sirens. Do not be alarmed. This is only a test.”

Christchurch City Council’s Civil Defence and Emergency Management Manager Brenden Winder said the re-test is essential after the previous scheduled test failed due to human error.

“We recognise the critical importance of testing the tsunami sirens and acknowledge the confusion that the earlier failed test created,” Winder said.

“We’ve had discussions with our supplier and we have sufficient safeguards in place to ensure this test will go ahead as planned. It is only a test and there is no need for anyone to evacuate.”

The council said reminders would be issued closer to the test date.

In the event of an actual tsunami threat, authorities would use multiple channels to warn residents, including the Emergency Mobile Alert system, radio, television, social media, tsunami sirens, and local community networks.

Residents can check whether they live or work in a tsunami evacuation zone by using Christchurch City Council’s online interactive map. Further evacuation tips and safety advice are also available on the council’s website.