How climate change and earthquakes could impact Kaikōura

Nicole Mathewson Reporter from The Press

By local democracy reporter David Hill

Climate change and future earthquakes pose serious risks for smaller districts like Kaikōura, the region's council boss says.

The alpine fault and rising temperatures pose various problems for the region. Climate change will bring the risk of more intense rain, landslips, alpine erosion, and increasing ocean acidification.

Kaikōura District Council chief executive Will Doughty said councils must work together to tackle these issues.

"Climate change related issues are multiple and varied across the region with different priorities for each district.

"Two of the main areas for concern for our district include changing weather patterns, in particular more intense rainfall, more frequently."

Loose material from the mountains generated by the earthquake caused an ongoing risk, while rising sea temperatures threatened marine species, he said.

The council would consider what further actions needed to be taken as part of next year’s 2024-34 long-term plan, he said.

Doughty welcomed the chance to also be included in the Canterbury Mayoral Forum’s Canterbury Climate Plan Partnership.

Environment Canterbury chief scientist Dr Tim Davie, who is leading the project, said councils must protect infrastructure, such as roads and drinking water, tackle coast erosion and look after biodiversity.

"[The climate partnership plan] is about pulling together and identifying what actions councils are taking and what we can do across Canterbury."

The 2016 Kaikōura earthquake caused an uplift of the coastline, reducing the impacts of sea level rise and coastal erosion in the immediate future, Davie said.

However, he said the region had other challenges including increasing ocean acidification. This was caused by oceans absorbing carbon dioxide from the atmosphere, which affected shellfish and other fish species

Warmer seas caused by climate change also impacted birds like the Hutton's shearwaters, which had to fly further in search of food, as fish moved to cooler waters.

Climate change was likely to create more issues around erosion in the mountains, as fragile alpine eco-systems moved to higher altitudes as temperatures rose.

Predictions around an alpine fault magnitude 8 earthquake show a significant amount of landslips could also bring down sediment and gravel, he said.

The 2016 earthquakes moved a considerable amount of shingle into the headwaters of the Kowhai River, which needed another event to shift it downstream, Davie said.

In 1993, the Kowhai River burst its banks and flooded homes and the main street of Kaikōura.

"When you drive along the coast it doesn’t make sense because the river seems to be a long way from the town."

But the river can change course in a flood or earthquake, he said.

PHOTO: King Charles III (left) visited the Hutton’s shearwater colony on the Kaikōura Peninsula with Hutton’s Shearwater Charitable Trust chairperson Ted Howard during a visit in 2019. The birds are threatened by rising sea temperatures and predators. (Supplied by Department of Internal Affairs)

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