High costs and hard decisions loom as Auckland Council works on plans to battle the effects of climate change

High costs and hard decisions loom as Auckland Council works on plans to battle the effects of climate change
Auckland's Maraetai Beach will be part of a council coastal management plan looking at the effects of climate change.

The Auckland Council has started work on a series of coastal plans to deal with the effects of rising sea levels and climate change.

The first four plans are expected to be completed by June next year and are in-line with Ministry for the Environment guidelines. They cover the Whangateau Estuary (including Omaha Beach), South Manukau Harbour, Whangaparaoa Peninsula, and Maraetai through to Matingahari. Coastal plans will eventually be completed for the entire Auckland region.

A report to the council’s Environment and Community Committee says each plan will look at the likely risks in a specific area over a 100-year period and will include an inventory of council assets and private property that may be affected.

“Due to Auckland’s density to coastline ratio and the significant proportion of Auckland’s development that is concentrated towards the coast, Auckland faces a number of coastal management challenges. These challenges include coastal hazards such as erosion, inundation and potential tsunami risk, the changing coastline, and the expectations of the role of council and communities in managing these challenges. Impacts of any coastal hazards will be influenced by the future effects of climate change.”

The council says collecting data from a number of different studies that are already under way will be vital to creating the coastal management plans. They include a regional erosion study, which is due to be completed in December this year and a study on a coastal inundation survey, which is due in November.

“Climate change is predicted to increase the current rates of erosion, mainly as a result of sea level rise. This study will provide site-specific data for the coastal plan development process, in particular the understanding of how erosion under the ‘do nothing’ scenario (with no or limited coastal defences) will change our coastline over the next 100 years, including anticipated climate change effects.”

While work is also under way looking at the impact of coastal inundation, which includes high tides, storm surges and/or large waves, and will provide much-needed data for the reports.


A first series of technical reports will be due early next year. They will outline the coastal hazards which are expected to affect each area.

“This will form a site specific risk assessment (hazard exposure and vulnerability) over different time periods for both private and public infrastructure. Based on the site’s risk, a range of mitigation options will be presented, ranging from managed retreat of infrastructure, through to hard and soft coastal defence solutions.”

There will then be a consultation process with asset owners, communities, mana whenua, ward councillors and local boards. 

Then a second stage of reports will outline the preferred approach and address the timing, feasibility and funding issues involved in implementing the plans.

High costs and hard decisions

But the report says climate change adaption will be costly and the council will have to make some tough decisions about which areas can and can’t be saved.

“Mitigating coastal hazards will become increasingly expensive. It will not be affordable or feasible to defend everywhere and the commissioning of coastal plans will result in significant decisions that need to be made by council. The coastal plans are intended to provide the evidence base and decision matrix to support appropriate decision making.”

"Improved knowledge (baseline data), and understanding with respect to climate change impacts, will likely result in an increased funding requirement for management of coastal assets.

Local Government New Zealand (LGNZ) released a report in January titled, Vulnerable: The quantum of local government infrastructure exposed to sea level rise. It looked at the cost to councils from rising sea levels and said up to $14 billion of local government infrastructure was at risk. The report called on central government to urgently develop policies to help minimise the impact of climate change on New Zealand communities.

It also recommended the establishment of a National Climate Change Adaptation Fund to deal with the costs of rising sea levels and a Local Government Risk Agency to help councils understand and factor in the risk of climate change into their planning and decision-making. The report also recommended creating a National Master Plan so it could work with the owners of affected infrastructure to plan for rising sea levels.

Since the report was released the Government has pressed ahead with its Climate Change Response (Zero Carbon) Amendment Bill, which passed its first reading in Parliament in May.

Under the legislation the Government plans to create a Climate Change Commission, but there’s no mention of a National Climate Change Adaption Fund. The costs associated with dealing with climate change continue to be an issue that hasn’t yet been addressed. But the ongoing work being done by Auckland Council and other local authorities around the country only serves to highlight the elephant in the room.

We welcome your comments below. If you are not already registered, please register to comment.

Remember we welcome robust, respectful and insightful debate. We don't welcome abusive or defamatory comments and will de-register those repeatedly making such comments. Our current comment policy is here.


I wonder how we will cope with the massive 1-2mm per year.
NIWA's 1998 Lyttelton study yielded a 1mm/yr sealevel rise

Cherry picking data from 1998? There's some confirmation bias for you. It's actually at around 3mm right now.

The rise is also non-linear, expecting to rise 65cm by the end of the century. NIWA also state "research has shown that sea level in the wider New Zealand area will rise by 5-10% more than the global average". This will have global implications.

Just one example....from our govt site
"Due to the influence of regional climate trends and gravitational effects, sea level does not rise uniformly around the globe. Sea levels in New Zealand rose on average by 1.7 mm per year from 1900 to 2008"

Well it only took 100 years of measuring for it to be declared a climate emergency. What was the rate of rise before 1900? Probably zero because climate change wasn't invented.

There you go again cherry picking the last 110 years of data. You denier you. The story is pretty consistent around the world, corrected for local subsidence most places have sea level rises of about 1-2mm/year over last 100+ years. And what is really inconvenient is that so many places saw peak 50-year sea level rise trends in the middle of last century, lower since, hardly a sign of 'acceleration'. https://tidesandcurrents.noaa.gov/sltrends/50yr.shtml?stnid=9410170

Cherry picking San Diego?

I went and checked NOAA (the source you cited) and their projections for sea level rise are more concerning than you make out.

Global sea level has been rising over the past century, and the rate has increased in recent decades. In 2014, global sea level was 2.6 inches above the 1993 average—the highest annual average in the satellite record (1993-present). Sea level continues to rise at a rate of about one-eighth of an inch per year.

And to your point of cherry picking, and your decision to cite the example of San Diego:

Just as the surface of the Earth is not flat, the surface of the ocean is also not flat—in other words, the sea surface is not changing at the same rate globally. Sea level rise at specific locations may be more or less than the global average due to many local factors

I'm not sure that the NOAA actually agrees with you that sea level rise is not happening nor a concern for the future.

The problem with sea level rise for the hand wringers is that the rise started prior to post WW2 industrialisation so the link with atmospheric CO2 is weak. From the AR5... "Chapter 3 concludes that the GMSL trend since 1993 is very likely higher compared to the mean rates over the 20th century, and that it is likely that GMSL rose between 1920 and 1950 at a rate comparable to that observed since 1993. This recent higher rate is also seen in tide gauge data over the same period, but on the basis of observations alone it does not necessarily reflect a recent acceleration, considering the previously reported multi-decadal variations of mean sea level."

Just pointing out that NOAA does not agree with Foyle. Fundamentally, the sources people are citing do not support the contention that "there's nothing to see here, global warming is made up tralalalala."

From the document you've linked:

It is virtually certain that global mean sea level rise will continue beyond 2100, with sea level rise due to thermal expansion to continue for many centuries. The amount of longer term sea level rise depends on future emissions.


There is high confidence in projections of thermal expansion and Greenland surface mass balance, and medium confidence in projections of glacier mass loss and Antarctic surface mass balance.


The available evidence indicates that sustained global warming greater than a certain threshold above pre-industrial would lead to the near-complete loss of the Greenland ice sheet over a millennium or more, causing a global mean sea level rise of about 7 m.

Don't disagree with any of it - sea levels rise in inter-glacials. Nothing presented here for councils to worry their poor heads about.
"The climate in the northern regions has never been milder since the last Ice Age than it was about 6000-7000 years ago. We still don’t know whether the Arctic Ocean was completely ice free, but there was more open water in the area north of Greenland than there is today,” says Astrid Lyså, a geologist and researcher at the Geological Survey of Norway (NGU)."

I am amazed that something that might happen or might not happen in 100 years is getting priority over many other essential priorities that need to happen now. You know its all political when that starts to happen.

I'm amazed when preceding generations thought a lot about leaving a better place to those who followed that so many today are only concerned with themselves. Perhaps where the Me Generation moniker originated from.

Climate change continues to relentlessly generate ever more studies and plans. Count how many new studies, funds and plans are in this article and this is only one tiny city in the world. It's hard to imagine any sane scientist disbelieving in climate change.

"And that is called paying the Dane-geld;
But we've proved it again and again,
That if once you have paid him the Dane-geld
You never get rid of the Dane" Rudyard Kipling.

Can we raise the level of debate, folks?

The obligation of LG is to do exactly what they're doing.

The overarching issue is funnier, though It is the entropic exhaust-gases of our burning of the one-off bonanza that was fossil fuels, that it doing the greenhousing anyway. But they'll be relying on Fossil Fuels to do the work. And relying on fossil energy being available for ratepayers to do work to pay rates. The whole thing get's overtaken by events - most likely a financial implosion, lack of trade, trend to the local, trend away from cities to food-productive land....... Many of the sites will just be sequentially abandoned, by an increasingly stressed populace.

And as for the elite cohort who think they can buy coastal and socialise the costs of defense, the mechanisms won't be there.

Sea levels are rising and will continue to do so. Anybody who builds on a beach or estuary is mad and should not be able to rely on others to bail them out, no joke intended.

Except for the hundred-plus kilometers of coastline between Oaro and Marfell's Beach, where SLR is irrelevant for the next millennium, because the whole shebang got booted oopards between 1500 and 4500 mm a coupla years back. Ditto Wellington foreshore in 1855: +1500mm

Practical SLR is SLR plus or minus tectonics. And as the Those Wot Know Best in LG and Gubmint are terminally clueless about the second half of That equation, perhaps the best way forward is to plonk a sturdy concrete cube every K along the beach in possibly-affected areas, run a standard survey across the things every decade or so, and set trigger points: If Measured SLR > X then Y action follows. Then STFU for another decade if the trigger has not been pulled.....

I do worry about the effects on the children (think of the children!) of all the doomsaying. Humans have managed to survive warm periods (Roman, Mediaeval) and Ice Ages (even Little ones, like 1300-1850) albeit with die-offs as carrying capacity was swamped by over-exuberance during past Good Times. There's no good reason to warp young minds, to the point of contemplating suicide, with such gloomy (but oh-so-well-funded) model-based projections. It's Child Abuse, IMHO.

By all means Measure and set trigger points. But prediction, as Yogi Berra was wont to say, is difficult, especially about the Future. And one can add, especially so when based on unfit-for-purpose Models....the Hawkmoth effect rules....

Indeed, it becomes an issue for local governments if people are choosing to buy in locations that are likely at greater risk from sea level rises only to expect to be bailed out in future, even if they didn't believe climate change was real.

Oh for goodness sake , maybe we should actually wait until there is hard evidence of rising sea levels before this financially strained council embarks on another wild goose chase with ratepayers money ..........

Climate denier! Burn him! Burn him!

Boatman - sea-levels are the least worry to someone with your mindset.


It's not only the Councils are heading down the 'financially strained' track.