Work to better manage the risk tsunami pose to Tairua and Pauanui is well advanced, says a report to today’s meeting of Waikato Regional Council’s catchment services committee.
The work is progressing under the auspices of the Eastern Coromandel Tsunami Strategy, involving the regional council, Thames-Coromandel District Council (TCDC) and local communities.
A new assessment of tsunami risks at Tairua and Pauanui says there is a significant threat to these communities if there is a major earthquake in the southern end of the undersea Tonga-Kermadec trench to the north-east of New Zealand.
A quake in that section of the trench similar in size to the 1960 Chile earthquake would see tsunami overtop the Tairua and Pauanui sandspits, the assessment said. A quake as big as the 2011 Japanese earthquake would result in severe inundation along the Pauanui peninsula and overtopping of its southern end.
There would be a very severe risk to people and property in such circumstances, especially given the relatively short warning time that a tsunami generated in the Tonga-Kermadec trench was on its way.
It’s believed big quakes in the trench may happen every 600 to 800 years. Evidence suggests a very large tsunami triggered by a source close to New Zealand last happened in the 14th century.
A report to the committee said a tsunami project for Tairua and Pauanui, supported by the local community board, aims to:
Over the coming financial year, activities to be carried out include the convening of a community working party, development of a communications plan and public education material, the holding of an open day and development of a risk mitigation strategy.
“It’s really great to be working closely with TCDC and the community board on ways of making the Tairua and Pauanui communities safer,” said the regional council’s community safety programme manager Adam Munro.
“The work we’re doing now is an investment in the future safety of the community and its ability to respond to and cope with a major tsunami.”
Tairua and Pauanui already have a well-established evacuation plan and warning sirens, while the community is primed to head for higher ground if they feel a major shake, said Mr Munro. “We strongly encourage the community to identify their evacuation route to higher ground and where they will head to before an earthquake. That way when they feel the ground shake violently then can move to protect themselves and their families in a planned fashion.”
Mr Munro said work this year will build on what’s already in place and look at longer-term issues for the community to address.
The wider Eastern Coromandel Tsunami Strategy has already addressed risks at Whitianga, which is considered the district’s town most prone to the impacts of tsunami due to local geographic features which enhance the risk.
That work at Whitianga has covered such activites as public education, land use planning and a risk reduction programme.
Tairua and Pauanui are considered the area at the next highest risk after Whitianga. Areas to be addressed in future include Whangamata, Matarangi and Cooks Beach.