New Zealand / Local Democracy Reporting

'Dithering' on tsunami sirens gone on too long - ex-councillor

18:11 pm on 29 April 2022

Tsunami sirens for Mount Maunganui and Pāpāmoa have been talked about for nearly 20 years but, despite having funding, council want to remove them from their work programme.

Photo: Sun Media

In 2019 Tauranga City Council approved a budget for the sirens, something then councillor Steve Morris was "really pleased" about.

Morris has advocated for sirens for at least 12 years and thinks they should be a priority as a secondary warning system.

Council has just finished consulting on the use of tsunami sirens as part of 2021-31 long-term plan.

The cost of the sirens is $3.9 million with an ongoing cost of $209,000 per annum, according to council.

Morris said this is a small price for "critical, potentially lifesaving infrastructure", especially in comparison to the $300 million council is proposing for the build of a new civic precinct in the Tauranga CBD.

"I think it's a matter of priorities.

"The first thing is to actually understand what a siren is for and that is as a backup to the primary mechanism, which is the natural warning signs, and not to get bogged down in the bureaucratic arguments about it."

Council emergency management manager Paula Naude said there are pros and cons to tsunami sirens.

"International evidence shows us that the risks associated with community reliance on a siren to know when to evacuate can be more dangerous than no siren," she said.

"The best and most reliable warning system for local source tsunami in New Zealand is the natural warning."

The natural warning is if an earthquake is long or strong people should evacuate and not wait for an alert.

"There have been advances in knowledge, data and technology since sirens were first discussed for Tauranga," said Naude.

"Based on the best available information, it is no longer considered that sirens are the safest solution for our community."

Former Tauranga city councillor Steve Morris Photo: Supplied

Emergency Management Bay of Plenty director Clinton Naude said the BOP Civil Defence Emergency Management Group does not regard sirens as an effective or a reliable alerting mechanism in local source tsunami events.

He said there are currently no sirens in the region.

The Bay of Plenty CDEM group includes the seven councils from the region.

These are: Bay of Plenty Regional Council, Tauranga City, Western Bay of Plenty, Whakatāne, Kawerau, Ōpōtiki and Rotorua Lakes councils.

Naude said some disadvantages of tsunami sirens were local source tsunamis could arrive within minutes, so there may not be time for an official warning.

"Sirens may also be damaged by the earthquake itself and therefore cannot be activated," he said.

"Sirens are known to cause complacency, which undermines the most reliable warning system for local source tsunami - the natural warning itself."

If evacuation is required, alerting systems include the emergency mobile alert (EMA), radio, television, social media and loud hailers, said Naude.

Despite the other systems available, Morris said there is still community support for sirens.

"What we found with Mount and Pāpāmoa residents in particular, is that they wanted an addition to the text message system and knowing the early warning signs," he said.

"They wanted to be alerted via public siren system as well."

In 2012, the Pāpāmoa Residents and Ratepayers Association (PRRA) set up temporary air raid sirens and conducted their own tests.

Morris was chairman at the time. He said the sirens were widely heard in Mount Maunganui and Pāpāmoa.

He said this "really annoyed" the council of the day, but it showed sirens could be widely heard.

Pāpāmoa Residents and Ratepayers Association chairman Philip Brown Photo: John Borren / Sun Media

Current PRRA chairman Philip Brown said the association thinks sirens are essential.

"We've always asked for them," he said.

"We always thought they are part of the mix of getting the warnings across and the evacuation message across, we've never deviated on that.

"The fact that there are other high tech solutions coming along, we think sirens are a great complementary fit."

When asked what he thought of removing sirens from council's work programme, Brown replied: "Do they want to kill people?"

He said there are limitations to the EMA.

"Not everyone has a cellphone, not everyone hears their cellphone," said Brown.

"Not everyone wakes up for their cellphone, but with a continuously sounding tsunami siren they will wake up."

He said there's no quick inland escape route for people in Mount Maunganui and Pāpāmoa so people need as much warning as possible.

Plans to install sirens along the Western Bay of Plenty coastline were launched in 2005 after the 2004 Boxing Day tsunami in Indonesia.

Back in 2006, 10 sirens were tested between Waihi Beach and Pukehina, however "black spots" were discovered where the sirens couldn't be heard.

Both Tauranga City Council and CDEM Bay of Plenty were unable to tell Local Democracy Reporting if this resulted in sirens being installed due to a lack of "sufficient information".

Morris wants to see action on siren installation rather than more consultation.

"The dithering and dragging out has gone on way too long in my view."

Local Democracy Reporting is Public Interest Journalism funded by NZ on Air