
Christchurch Tsunami Sirens Face Axe After Failed Test, Communication Breakdowns
A scheduled test never happened, when the Auckland-based contractor was distracted by a car accident.
The number of tsunami sirens along the Christchurch coast could be cut to as few as four, after an alert system review that found they cause confusion and delays during emergencies.
The city has 45 sirens between Brooklands and Taylors Mistake, but next week, Christchurch city councillors will consider a recommendation that would see them only positioned in evacuation zones with limited cell phone coverage.
The report recommended the council primarily uses emergency mobile alerts to raise the alarm, in accordance with national and international best practice, moving from a 'fragile, unreliable, over-complicated and inconsistent' alerting system to one that was 'straightforward and effective'.
Fewer strategically positioned sirens – in the range of 4-6 – and emergency services, television, radio, website and social media messages would become the secondary alerting method.
Christchurch's tsunami sirens failed to sound during a planned test in April, because the Auckland-based contractor responsible was dealing with a car crash outside their property at the time.
The council initially blamed human error, then conceded having an emergency system so dependent on one person was unacceptable. The test was rescheduled for 13 July.
The council said a 'local-source' tsunami could inundate Christchurch and Banks Peninsula evacuation zones in less than 60 minutes, so its top priority was preventing loss of life with an alert system that gave a clear message to evacuate.
The review noted sirens caused confusion and delays because:
Warnings could be mistaken for different hazards, because of multi-purpose sirens like rural fire alarms
Sirens could create a false sense of security, with people waiting for official warnings that might not be issued in time
Sirens could distract from public education messages about responding to natural tsunami warning signs
Limited information was provided, requiring the public to seek further information before evacuating
Sirens were prone to damage or failure in an earthquake
Sirens could be inaudible in windy conditions
Sirens were established on ageing technology and infrastructure, and the network trigger could not be operated locally
Civil Defence and Emergency Management manager Brenden Winder said the emergency mobile alert method aimed to minimise confusion.
'In the rare event of a tsunami, our top priority is preventing loss of life,' he said. 'This relies on having a straightforward and effective alerting system, giving residents a clear message to evacuate.
'Sirens are no longer considered to be a suitable primary tsunami alerting method, as they cause confusion and delay communities responding effectively.
'Mobile alerts are used nationally as the main alerting method in an emergency. This sends a clear message straight to the user's phone on what action to take.
'We want people to act quickly and decisively in an emergency, and a text alert provides that direction.'
Staff said another option to upgrade the existing 45 sirens and add 41 sirens for adequate coverage across a new national tsunami evacuation zone issued by the National Emergency Management Agency would come at a substantial cost to the council.
Following the magnitude 7.8 Kaikōura earthquake in 2016, a communication breakdown meant Christchurch's sirens did not sound until two hours afterwards at 2am – an hour after Civil Defence issued an alert.

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles

RNZ News
2 days ago
- RNZ News
Flight lands safely at Hawke's Bay Airport after Fire and Emergency callout
File pic Photo: RNZ / Nate McKinnon Fire and Emergency (FENZ) was on standby at Hawke's Bay Airport on Friday morning at the request of an inbound Air New Zealand flight. However, around 8am the flight landed safely, an Air New Zealand spokesperson said. "The crew operating NZ5025 from Auckland to Napier this morning received a maintenance alert during the service," the spokesperson said. Chief operating officer Alex Marren said emergency services were called in line with standard operating procedure after such an alert. The aircraft landed safely and the airline's maintenance team would now inspect the aircraft before it was returned to service. FENZ shift manager Chris Dalton earlier said three crews were at the airport as a precaution after an aircraft indicated a possible "situation on board". He said larger airports had their own fire brigades, but in regional areas FENZ was called in to help. Dalton said there had been no suggestion of an emergency. Sign up for Ngā Pitopito Kōrero, a daily newsletter curated by our editors and delivered straight to your inbox every weekday.

RNZ News
3 days ago
- RNZ News
Providers say it's time to rethink alternate education
The founder of one of the country's longest-running alternative education organisations, is urging a re-think on how the sector is viewed, and the students that come through its doors. Over the past fifteen years, approximately 23,000 young people have gone through alternative education (AE) programmes. These are programmes that sit outside mainstream schools, aim to provide young people with a quality education and to support them into education, training, or work. Lloyd Martin, who founded provider Praxis in the 1990s recently completed research into the experiences and perceptions of young people in AE. He says the programmes, which run off of a fraction of the funding that mainstream schools get, are a lifeline. Meanwhile, on Auckland's North Shore, Cameron Fisher is running a pilot programme for pupils too young for AE programmes. He explains why it's working. Students learning in a school classroom. Photo: Unsplash/ Taylor Flowe

RNZ News
3 days ago
- RNZ News
Pacific Waves for 19 June 2025
Auckland flood residents still facing uncertainty; Debate on deep sea mining in the Cooks ongoing; Moana Pasifika's inspirational captain leaves for Japan. Tags: To embed this content on your own webpage, cut and paste the following: See terms of use.