Tsunami threat: A question of timing

Otago Civil Defence and Emergency Management Group regional manager Chris Hawker, at St Kilda...
Otago Civil Defence and Emergency Management Group regional manager Chris Hawker, at St Kilda beach, says our tsunami alert system needs to be improved.
Karitane residents Rose Stringer-Wright and Richard Russell — both members of the Waikouaiti...
Karitane residents Rose Stringer-Wright and Richard Russell — both members of the Waikouaiti Coast Community Board — say tsunami warning sirens are needed in the settlement. Photo: Gregor Richardson.
Taieri Mouth resident and holiday camp owner Paula Poutu was not alerted until 5am, hours after...
Taieri Mouth resident and holiday camp owner Paula Poutu was not alerted until 5am, hours after the first wave of last month’s tsunami was due to arrive. Photo: Gerard O'Brien.

Otago’s coastal communities dodged a bullet when a tsunami generated by last month’s Kaikoura earthquake took aim at the South. Now the race is on to be ready when the next one strikes. Chris Morris reports.

Chris Hawker says Otago never stood a chance.

From the moment the shaking subsided after Kaikoura’s 7.8-magnitude earthquake struck at 12.02am on November 14, the clock was ticking towards the arrival of a tsunami up to 3m predicted for Otago’s coast.

It was a countdown that did not have long to run, as authorities estimated the first wave — travelling at speeds of up to 1200kmh — would be washing down Otago’s coast from 1.25am.

That was just 29 minutes after Mr Hawker, the group controller in charge of Otago’s Civil Defence efforts, received a warning from Wellington that the tsunami was on its way.

• Calls for fast-tracked tsunami alert system backed

• Serious tsunamis a real possibility

Had the predictions proved accurate, the speed of the first wave meant there would not have been time to warn people to escape from its path, Mr Hawker told ODT Insight.

"Unfortunately, that is a reality. The problem we had with the tsunami, and it is a big problem, is we didn’t have time.

"The chance of actually doing anything substantial from a Civil Defence response perspective in 20 minutes is almost nil," he said.

The bullet was dodged when the 2.5m tsunami waves recorded at Kaikoura reduced to 1m by the time they hit Christchurch and dissipated completely before reaching Otago’s shores.

But Mr Hawker conceded it was sheer luck residents in Otago’s low-lying coastal communities were not woken by a wave, rather than a warning.

"Yes, that’s a possibility," he said.

It was a blunt reality for a city of 125,000 people living on an exposed southern coast: when earthquakes struck close to shore, with the power to trigger a tsunami, there was no time to warn everyone.

And although people were educated to evacuate premises by themselves after powerful or prolonged ground shaking, that was no use to those who slept through a quake that occurred more than 400km away.

While those who felt it and heeded warnings headed for the hills, many more slept on in Dunedin, unaware of what was unfolding.

It is a problem that has already prompted Prime Minister John Key to say plans for a new national alerting system will be accelerated.

That was backed by Mr Hawker, who said an "intelligent" automated system — be it sirens, text messaging or some other technology — was needed, alongside greater public education, to protect people.

Dunedin’s response would also be reviewed, as there were "some pretty difficult questions that we have to ask ourselves in a very short space of time".

"We’ve got so many communities that the only resource that’s close [to wake them] is the volunteer fire brigade.

"And by the time you activate them and they get their pants on and into the machines and heading in any direction, it’s past the arrival stage of probably even the second wave," he said.

That was a concern in Aramoana, where volunteer firefighters from Port Chalmers were not activated until 3.20am to begin evacuating residents.

The firefighters moved through the town, sounding their truck’s siren and door-knocking, to wake residents to ensure they knew of the threat.

But Aramoana resident John Davis said the evacuation would have come hours too late for any residents who slept through the initial earthquake if the tsunami’s first wave had arrived.

He was aware of the advice to head for high ground after a powerful earthquake, but the November 14 quake did not fit the bill — at least in Dunedin.

"It woke me, but it wasn’t the one that threw me out of bed to say ‘s..., we’ve got to move’."

Instead, he monitored "conflicting" media reports about the need to evacuate from 1am, and waited for a firefighters’ siren to notify the town of an evacuation.

Residents who continued sleeping would have been unaware of the threat until the brigade arrived, he said.

"Full marks to the fire engine system for getting us woken and out of bed. The question, really, is the timing."

He also questioned why those who had been evacuated were sent along Aramoana Rd to Port Chalmers — a 15-minute drive virtually at sea level — instead of making for the high ground around Aramoana.

"If there was a tidal movement of any sort, they’re actually sending us to trouble, not getting us out of trouble."

He also worried about firefighters sent into the path of the predicted tsunami. Port Chalmers Volunteer Fire Brigade Chief Fire Officer Stephen Hill said he could not discuss the merits of the response plan, but, once activated, his brigade took just 15 minutes to reach Aramoana.

"We treat it just like anything else."

New Zealand Fire Service Otago and Southland assistant area commander Rodger Smith said the approach needed to be reviewed, including the timeliness of the Civil Defence response and the safety of volunteer firefighters.

"That is a genuine concern."

West Harbour Community Board chairman Steve Walker was among those to sleep through the quake, having turned off his phone, and was unaware of the tsunami evacuation on his doorstep until the next morning.

He was concerned the delayed response could have been fatal, but also that he had missed a phone call from the Port Chalmers fire brigade at 3.40am, at the height of the evacuation.

The brigade did not have a key for the Port Chalmers Town Hall, despite it being the local Civil Defence centre, and wanted Mr Walker to let it in.

"I don’t actually hold a key, and it seems ridiculous to me that the fire brigade themselves don’t hold a key.

"This is a wake-up call for the future, to have a far more robust system in place."

It was a similar story in Karitane, where resident Richard Russell — a Waikouaiti Coast Community Board member — said the tsunami response had been "bloody hopeless, to be honest".

More than 50 residents had gone themselves to the Puketeraki lookout, overlooking Karitane, after being woken by the shaking or the messages from friends and family that followed.

But some Karitane residents slept through the earthquake and were  alerted only when firefighters knocked at their door about 4am, fellow resident and board member Rose Stringer-Wright said.

At least two people were also missed altogether in the evacuation, despite potentially being in the tsunami’s path, she said.

Ms Stringer-Wright and Mr Russell agreed the response highlighted the need for dedicated tsunami warning sirens along Dunedin’s coast.

Karitane had no fire brigade and no fixed siren, and the nearest — in Waikouaiti — could not be heard "if the wind’s blowing the wrong way", Mr Russell said.

"It’s a real Mickey Mouse thing. This was a real good wake-up call.‘‘One day, indeed there will be a tsunami, but because there hasn’t been one, everyone’s a bit ‘oh yeah — it won’t happen’.

"It’s a big problem."

The evacuation of Taieri Mouth homes also raised concerns for resident Alvin Swete and Taieri Mouth Beach Holiday Camp owner Paula Poutu.

Mrs Poutu said she and about 15 international tourists staying at the camp were  woken by firefighters only about 5am and evacuated to the nearby Taieri Mouth hall.

By 6am, they were allowed to go home again.

While praising the firefighters’ efforts, the evacuation would have been "a lot quicker and easier" if Taieri Mouth had its own dedicated tsunami siren, she believed.

A text alert system would not work because of the settlement’s communications black spots, she said.

Mr Swete said he was "flabbergasted" by the slow response, as those sent to evacuate residents door-knocked empty homes and cribs at 4am.

"By the time they got there, it was too late.

"We all would’ve been washed out to sea before we had a chance," he said.

Some evacuated residents were also sent into the path of any tsunami by being told to cross the Taieri River bridge to reach the Taieri Mouth hall, which was itself a communications black spot, he said.

The confusion was also evident in Dunedin’s urban centre, where hundreds of people took to Facebook desperately seeking information about the tsunami threat and the need to evacuate.

That included residents in South Dunedin, reacting to advice from Wellington for people in low-lying areas to evacuate.

It was not until 3am that Dunedin Civil Defence staff reassured residents in South Dunedin they were safe, by which time some had already left.

In the meantime, others, including members of the public and Labour’s Dunedin South MP, Clare Curran, started filling the void by sharing their own advice on the Dunedin Civil Defence Facebook page.

The confusion was also replicated at a national level as scientists rushed to pinpoint the quake’s location and the likelihood of a tsunami.

The Ministry of Civil Defence and Emergency Management, in a message on Facebook at 12.39am, initially concluded there was no tsunami threat.

It then reversed that at 12.57am, saying "the situation has changed" and people on the South Island’s east coast should move to high ground.

For Mr Hawker, Dunedin’s response highlighted the vulnerability of Otago’s coast and the need to continue improving the city’s ability to respond to a tsunami threat.

That work had already begun, with a new regional model for Otago’s Civil Defence arrangements, headed by Mr Hawker, launched on November 1.

A new website had since been launched to help educate the public and plans for new social media platforms would help improve communications during major events, he said.

New community plans, detailing agreed responses to specific threats such as a tsunami, were also to be prepared, and the location of some Civil Defence centres reviewed, he said.

But last month’s tsunami underscored how much there was to do, and the need to get on with it, he said.

"It wasn’t a wake-up call that we’ve got to get our act together. We already were ... [but] we can’t sit around and say ‘let’s do that next year’. We’ve got to be as proactive as we possibly can.

"I’m certainly not going to be glib and tell you that everything’s perfect and you don’t have to worry about it, because it’s patently not," he said.

chris.morris@odt.co.nz

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