New Zealand / Environment

Coastal erosion could see 100 Hawke's Bay properties go in 20 years - report

16:28 pm on 14 July 2022

Hawke's Bay's dramatic coastline, with its houses often blasted by wild weather, may change completely as rising sea levels threaten to force people from their homes.

Residents of properties on North Shore Rd in Whirinaki, just north of Napier, could have to retreat in the next 20 years as the sea splashes up on to the road. Photo: RNZ / Tom Kitchin

A new report says erosion could see more than 100 coastal properties disappear over the next 20 years.

Local authorities are struggling with the question of whether it is better to retreat or build defences against the ocean.

Whirinaki is just north of Napier, right on the edge of the coast. Huge swelling waves crash on to the shore, and sometimes on to the road, near houses only a few metres away.

The report, 'Implementation approaches and indicative costs for planned retreat' by Tonkin and Taylor, prepared for the Hawke's Bay Regional Council, found if nothing was done in the next 20 years, people living in 43 houses in Whirinaki could have to pack up and move away.

Resident Richard Fergusson said he wanted to stay put.

"I won't be moving, no .... why should I move?"

He enjoyed living in the area. "It's great, I love it. You can see the sea, sometimes it's wild, sometimes it's not. You can fish here, you can do what you like."

Olivia Finlay, who lives down the road from Fergusson, felt torn about potentially retreating.

"I've got a bit of mixed emotions. We've had the sea come quite far up, but it's never gone anywhere near the other side of the road and 'cause we're on the opposite side we're quite far away. But then again, I see the point because we are so close."

But she would still rather not move.

"I'd hate it, I love this house, I love living on the beach.''

Huge waves crash on to the shoreline at Whirinaki Photo: RNZ / Tom Kitchin

Planned retreat, as it is called, is estimated to cost the region about $2 billion over the next 100 years, moving people away from nearly 1000 homes in that time.

At Haumoana, south of Napier on the Cape Coast, Keith Newman is chairman of Walking on Water, a local advocacy group.

A storm in just the last few days caused further problems along the coastline, Newman said.

"It had a bit of an undertow with it and as well as coming up to the crest it also took away a bit of shingle and did a bit of damage right along the Cape Coast stretch. It took away some concrete blocks that people had protecting their properties."

The Tonkin and Taylor report said residents of 21 homes in Haumoana could have to retreat in the next 20 years .

That made Newman fearful and he had many questions.

"We know that there are elements along here where it may still have to happen, but the cost of it is huge. So where do you put people when they have to go somewhere or else who pays for you to move? What's the replacement cost? Is there some compensation? Do you have to go voluntarily or are you forced?"

He wanted investment into defence, like sea walls, and mentioned some already on the coast, such as at Cape View Corner between Haumoana and Te Awanga.

"It is geared engineering wise for a fifty-year life and it would have to be pretty heavy circumstances that would have rattled all of Hawke's Bay for those rocks and big rocks to be disrupted.

"It's been done professionally by people who know what they're doing and we feel safe."

Building defences is one option being considered by the Clifton to Tangoio Coastal Strategy Hazards Joint Committee, made up of representatives from three local councils and mana whenua.

The committee is developing a plan for the coastline, looking at defences and managed or planned retreated.

Chairman Jerf van Beek said they got the planned retreat report to compare options - he used the analogy of looking for a new car.

"Will they go EV, petrol or diesel? You cannot make that decision until you know what the costs are and what the long term running costs are and what the value will be at the end of the lifetime - we've done exactly the same here."

The report's findings would be part of the strategy, he said.

"So it doesn't define anything that we are going to do. We actually have got a draft strategy - we hopefully will make that a strategy that we actually will put in place n due time and that is what we are going to follow."

He could not say when the strategy would be completed, as there was further work to do.

Consultation was being carried out on whether the regional council should lead the strategy and there was more work to do on how groynes or sea walls could affect marine life.