Much to be learned from Exercise Horowhatu

Wednesday 18 October, 2023

A Tairāwhiti Emergency Management led exercise in response to a Hikurangi magnitude 9 earthquake off the Kermadecs will provide valuable information to the regional catastrophic event plan.

Yesterday, Exercise Horowhatu 2023 brought together the region’s response teams, agencies and organisations at the new Emergency Coordination Centre in Lytton West. It was run as a live scenario, with regular updates fed in as breaking news, exactly as it would in a real situation.

In the exercise, the earthquake generated tsunami waves that swept along the coastline through Hicks Bay/Wharekahika, Ruatorea, Tikitiki and Muriwai. These were the worst hit with waves of up to 15m high.

The city was completely inundated with fast-moving water and debris, with flooding right back to the Dalrymple and Ormond Road area.

Around the table were representatives from iwi, health, FENZ, Police, the New Zealand Defence Force, Ministry for Primary Industries, Gisborne District Council and more, all covering the functions of an actual emergency response – intelligence, operations, welfare, and public information.

TEMO general manager and group controller Ben Green says there is much to be learned by all in exercises like this.

“This provides a realistic environment to test and develop processes, procedures and exposure to people working in an emergency centre environment,” said Mr Green.

He said given the adverse weather the region had experienced in the past 18 months, those who were part of the responses were well-versed in what needed to be done. “The events we have been dealing with of late have been weather-related, so it was interesting to do an exercise around a big earthquake and subsequent tsunami.”

The Hikurangi Subduction Zone represents Aotearoa’s greatest seismic threat and the time between a rupture and tsunami arrival is minutes.

“That means we need solid plans in place to respond effectively to something that would create significant devastation,” said Mr Green.

Hikurangi is a valid concern given there is a 26 per cent chance of a significant event in the Hikurangi Fault occurring within the next 50 years.

“People are always at the centre of any emergency response which underlines the importance of these exercises.

“Our welfare arm provides for the needs of affected people, and we also have support to prevent escalation of situations and minimise the consequences of the emergency on whānau and communities.”

Exercise Horowhatu is the third such exercise run in Tairāwhiti by TEMO, with each feeding into the catastrophic event plan which is set to be completed in 2024 which will coincide with the development of the national plan.

Tairāwhiti will take part in a 2024 nationwide NEMA exercise which feeds into the development of the national Hikurangi plan Aotearoa New Zealand.