Tutukaka Wave Leads to New National Civil Defense Tsunami Warning Category

Damage inspection was the order of the day after the Tonga tsunami hit the Tutukaka marina. Photos / Tania Whyte

A new national civil defense tsunami warning category is being developed following the huge impact of the Tonga eruption on the Northland coastline.

No lives were lost when the tsunami hit Tutukaka Marina, but a woman was rescued in the darkness of the sea after falling overboard in powerful swirling currents as she attempted to descend from his damaged boat, in his canoe.

Millions of dollars in damage ensued with wrecked and sunken boats. Meanwhile, boats in the port of Whangaroa feared being cast adrift after the violent sea tsunami nearly forced their anchors.

The new notification would add specific references for boats in tsunami notification messages. This would bring New Zealand’s official tsunami advisory choices to three.

New Zealand has one of the highest rates of boat ownership in the world, but there are currently no tsunami warning options specifically targeting this area.

Northland Civil Defense will work with the New Zealand National Tsunami Task Force to eventually develop the new option.

The January 15 tsunami in Tonga hit Tutukaka Marina hard, destroying parts of the facility and sinking or damaging boats, causing more than $5 million in damage.

The investigation into a potential new advisory has emerged in a new 15-page report on the Tutukaka Marina tsunami following the event from Northland Civil Defence. Graeme MacDonald, Group Director of Northland CDEM, recently presented the report at a meeting of the Whangārei District Council (WDC) Community Development Committee. It was written by Northland CDEM specialists Tegan Capp and Evania Arani.

Sunken boats, boats, shipwrecked, semi-submerged boats - post-tsunami chaos at the marina
Sunken boats, boats, shipwrecked, semi-submerged boats – post-tsunami chaos at the marina

“One option is to request the creation of a new advisory of ‘strong and unusual currents and unpredictable surges which may, in some locations, be sufficient to pose a risk of injury to persons on board vessels,'” the report said. .

“None of the current options for the expected effects of the tsunami…are particularly suited to the risk for those who live either permanently or on shorter overnight cruises/holidays on the water,” the report said. The report warned of a residual risk of further Hunga Tonga-Hunga Ha’apai eruptions and landslides.

He said the effects on boats in Whangaroa Harbor were largely covered by the warning messages for “unusual strong currents and unpredictable surges”, but the risk of injury from the Tongan tsunami exceeded previous effects associated with such an advisory. .

“People aboard the boats in Whangaroa Harbor in particular, … experienced severe whirlwinds and surges to such an extent that they worried whether their anchoring equipment would fail under the load,” the report said. report.

New Zealand’s current two notification categories are an advisory and the other, more seriously, a warning. The advisory speaks of strong and usual currents and unpredictable surges and is used when the tsunami is not expected to propagate on land. The warning indicates that a tsunami will propagate over land and may include evacuation messages.

The January 15 tsunami hit the Tutukaka Marina in the absence of highly visible formal public warning systems such as the tsunami siren, emergency mobile alerts (EMAs) or Red Cross Hazard app notification .

Greg Martin, Tutukaka Marina Management Trust Trustee and Whangārei District Councilor, said the sound and flashing functions of the breakwater’s tsunami siren needed to be able to be individually activated to warn of impending tsunami danger.

Its flashing light can be activated individually by the marina management, its siren cannot.

Reflecting on the chaos at Tutukaka Marina during the Tonga Tsunami - Marina Manager Dylan Lease (left) and Tutukaka Marina Management Trust Member Terry Harris
Reflecting on the chaos at Tutukaka Marina during the Tonga Tsunami – Marina Manager Dylan Lease (left) and Tutukaka Marina Management Trust Member Terry Harris

He said the flashing light alone was not a working tool to wake up people who were sleeping inside their boats in the dark.

Capp said Northland’s tsunami siren network does not allow sirens to be activated individually. The network was however being upgraded with individually activated sirens, an option that could be considered.

Martin said a short-term resolution was needed, ahead of any bureaucratic processes that could be used that would take much longer to put in place.

There are three Tutukaka village tsunami sirens – on the marina breakwater, at the local cafe Schnappa Rock, and another near the village shop.

The report says that a pre-emptive local evacuation of Tutukaka Marina and surrounding buildings would have mitigated the risk to people.

This option should be worked out directly with the community – which could also include businesses and accommodation providers located in close proximity to the marina. This would recognize that the Tutukaka Marina was more vulnerable to potentially damaging power surges than other locations.

The marina community wanted to evacuate at lower thresholds, according to the report.
Any changes proposed by the Marina Management Trust would be part of this.

Meanwhile, people fishing for plaice on foot along the tidal edge the night the tsunami arrived on a stormy Saturday evening had to run for their lives when it hit their remote shore fishing spot west on the northern shores of Hokianga Harbour.

The Northland Civil Defense report says work is underway to establish better communication with Far North campgrounds evacuated when the Tonga tsunami landed, but outside of cell phone coverage and the existing network of tsunami sirens.

More needs to be done to be able to close the Tutukaka Marina and surrounding areas during the tsunami emergency cleanups, Martin said.

After the Sunday morning tsunami at Tutukaka Marina in Tonga
After the Sunday morning tsunami at Tutukaka Marina in Tonga

Hundreds of tourists set out from Whangārei to visit Tutukaka Marina on Sunday January 16 from early morning the day after the tsunami.

“We couldn’t move people the next day. We had cranes coming in and an emergency situation,” Martin said.

The village at sea level Marina Rd and surrounding area was packed with people and their cars. People sat at the adjacent Schnappa Rock cafe over coffee, watching what was going on. A single member of the emergency services at the east end of the marina parking lot was inundated by pedestrians walking the length of the facility after it was closed to vehicles. This all happened as tsunami waves continued and boat owners rushed to sort out sunken and damaged ships.

Martin said the area was not cleared until the Ngunguru Volunteer Fire Truck arrived, saving the day with its siren.

Sandra Boardman, chief executive of the WDC community – and Northland CDEM Group Comptroller – said Martin’s traffic management representations would be taken into account.