Landslides can affect homes, roads, infrastructure and services across Tāmaki Makaurau Auckland. As severe weather becomes more common, understanding where landslides are more likely to occur is becoming increasingly important.
In 2025, Auckland Council completed a region-wide study to identify areas that may be more susceptible to landslides. This study gives us a better understanding on the potential for landslides across the region and helps inform future planning and infrastructure decisions.
It’s important to understand that these maps provide a regional picture of where landslides may be more likely. They are not designed to assess risk for individual properties or predict when a landslide will happen.
Since the maps were published, we've received questions and concerns from property owners, buyers, and industry groups, particularly around what the maps do and don't mean for individual properties, and how they interact with Land Information Memorandum (LIM) reports, insurance, and site-specific reports.
We’ve collated some of the frequently asked questions with answers to help you understand what the maps show, how they were developed, and what to do if you want more certainty about a specific site.
Here’s some useful information on what the maps show, how they were developed, and what to do if you want more certainty about a specific property or site.
At a glance
In a nutshell, what do I need to know?
The maps provide a regional picture of where landslides may be more likely. They are not designed to assess risk for individual properties or predict when a landslide will happen.
These maps were created to support long-term land-use planning and growth decisions, helping guide development away from more susceptible areas and identifying where further where more detailed assessments or investigation may be needed.
Auckland Council is legally required under the Local Government Official Information and Meetings Act to disclose known or potential natural hazards on LIMs. These maps are part of that obligation.
This helps people decide whether further investigation, for example like checking property files for existing geotechnical assessments, or getting professional, site-specific advice is warranted.
These maps do not replace property-level assessments and would not necessarily have affected past consent decisions, as they do not determine site-specific risk.
Frequently Asked Questions
The landslide susceptibility maps
Why were the landslide susceptibility maps created?
The most effective way to manage the risk of landslides is to avoid building in areas at risk. While the risk can be engineered out in some cases, doing this is costly and not always effective.
The maps were created to support long-term land-use planning and growth decisions, helping guide development away from more susceptible areas and identifying where further where more detailed assessments or investigation may be needed.
The maps are intended to inform future changes to the Unitary Plan and to support council decisions on development and its own assets.
You can also learn more here: Auckland Landslide Susceptibility Study Factsheet [PDF 1.43 MB].
What does ‘landslide susceptibility’ mean, and how is it different from landslide hazard and risk?
Susceptibility shows how likely an area is to experience a landslide compared to other areas; it doesn't predict if, or when, a landslide might happen, or how serious it might be. This means they’re different from a hazard map (which would show where and how often landslides might happen in the future) or a risk assessment (which would measure the impact and consequences).
These maps only show susceptibility. The susceptibility ratings are not a measure of landslide risk on individual properties. Instead, they help Auckland Council understand regional conditions and make transparent, informed planning decisions for areas that may be more prone to landslides.
For example, landslide susceptibility looks at underlying factors which might increase the chance of a landslide occurring (like geology and slope angle). These factors raise the chances, but that doesn't mean every property with those factors will have a landslide.
How were these maps created and are they property-specific?
The maps were developed using regional information such as slope, geology, waterways, land use and records of past landslides. A specialist consultant used computer modelling to identify areas that share characteristics with places where landslides have occurred before.
The study assessed Auckland at a regional scale and did not include site-by-site geotechnical assessments of individual properties, as Auckland’s size makes that infeasible.
Why do the maps look the way they do, and why can’t they be viewed at property level?
They're shown at a broader (suburb) scale because they're built from regional statistical data; showing them at property level would suggest a precision the data doesn't have. The current scale allows users to see how a property sits within the wider area without altering the integrity of the data.
Why are there two types/maps?
The two landslide types were mapped separately because they differ in their impacts, and the geological conditions behind them.
How do you know this mapping is valid?
The study was completed by WSP, a consultancy with expertise in geotechnical and natural hazard assessment. The methodology and results were independently reviewed by a panel of five expert reviewers to help ensure the work was robust and fit for purpose.
Was a physical site inspection conducted, or is this based solely on a computer‑generated or desktop model?
This study was carried out using a computer‑generated model and datasets covering the entire region. Some limited onsite checks were done in selected areas to validate the results, but this didn’t include assessments of individual private properties. Full property-by-property inspection isn't practical or affordable at Auckland's scale.
When will these maps be updated?
We’re developing a programme for updating this and other natural hazard information as resources and new information become available. The next update is unlikely to be around 2028 depending on funding and research progress.
Land Information Memorandum (LIM) reports
Why is this information included on LIMs?
Auckland Council is legally required under the Local Government Official Information and Meetings Act to disclose known or potential natural hazards on LIMs. These maps are part of that obligation.
This helps people decide whether further investigation, for example like checking property files for existing geotechnical assessments, or getting professional, site-specific advice is warranted. It isn’t designed to be used alone to assess a specific property.
How do these maps relate to site-specific reports, property categories, or past consents?
Site-specific information, such as geotechnical reports, consent assessments or property categorisation information, is usually more detailed and more relevant to an individual property than regional mapping.
These maps do not replace property-level assessments and would not necessarily have affected past consent decisions, as they do not determine site-specific risk.
Can site-specific information be used to change the LIM or the maps?
Site-specific reports can provide valuable context for owners, buyers and insurers. However, they do not change the regional mapping or LIM disclosures themselves, which is based on a consistent method applied across Auckland.
The council also does not routinely monitor the condition of site-specific mitigation measures, such as retaining walls, over time.
I have a geotechnical report saying my site is stable – can that change the LIM or the maps?
You may have a site-specific geotechnical assessment that provides different findings. This may be a landslide risk assessment, a geotechnical report associated with building a home or structure such as a retaining wall, or similar advice from a chartered professional engineer or professional engineering geologist. You can hold and share that site-specific information (e.g. with insurers or buyers), and it's normally more relevant to your situation than the regional maps.
However, this doesn’t mean that we can change the underlying susceptibility maps.
Even where measures like retaining walls have been built, council doesn't amend the LIM to reflect them – partly because that detail belongs in site-specific reports read alongside the LIM, and partly because council doesn't monitor the ongoing condition of such structures. The LIM itself notes that hazard information doesn't account for interventions that may reduce (or, if poorly maintained, worsen) the risk.
What if there have been changes to my land, like earthworks?
The maps are based on aerial scanning and topographical data available at the time of the study. They may not capture more recent changes to landform, including some earthworks or development activity. The council updates this scanning data from time to time and will use updated topographical information in future updates of these maps.
Property value and insurance
Will these maps impact the value and/or insurance of my property?
The council cannot advise on property values, insurance cover or insurance premiums. If you have concerns about how this information may affect your circumstances, speak with a qualified valuer, insurer or insurance adviser.
These publicly available maps provide a regional view and shouldn’t be used for assessment of risk for individual properties.
Has my insurance company been informed on these maps and will it affect my ability to get insurance or increase my insurance premiums?
Information about the study has been shared with the Insurance Council of New Zealand. We have emphasised that the maps are regional in nature and are not intended to replace detailed site-specific investigations where those are available, and are intended to prompt further investigation where relevant, like checking property files or looking for signs like ground cracking.
We will continue to monitor how the insurance sector uses the information. For specific concerns, consult a valuation or insurance professional.
I’m buying a property – what should I consider?
The maps give an indication of landslide susceptibility but not landslide risk, and they aren’t able to take into account local features. They’re designed for use at a regional level, not for making site-specific decisions like purchasing a property.
If you find a property that is shown as having a higher susceptibility, look around the site to try and understand why. The maps were created without visiting the sites or using information about each property, so your observations on site will be more detailed and could be more relevant. Consider things like:
Slopes: are there obvious signs of movement like cracks in the ground or leaning fences on steep slopes?
Retaining walls: the regional model can’t take these into account because there is no regional map of retaining walls. This means that the susceptibility might be overstated. If there are walls retaining the slope, are they well built and maintained?
Stormwater: does stormwater from the roof or adjacent properties flow onto a slope? Are there springs appearing in the property?
Vegetation: have trees been chopped down (leaving bare earth), or left to grow uncontrolled so they might be exposed in a big storm?
The building: are there odd cracks in the façade, do doors or windows stick?
If you’re not sure, consider getting professional advice.
Auckland Council’s role
What is the council’s role in managing landslide risk on properties?
Our role is to identify, maintain and disclose natural hazard information at a regional level, and to use that information to support planning and decision-making. Responsibility for managing risk on individual properties generally sits with property owners, supported by professional advice where required.
Can Auckland Council arrange or review a site-specific assessment for me?
The council does not normally commission or independently verify geotechnical assessments for private property owners. If you wish to obtain a site-specific assessment, you should engage an appropriately qualified professional. Reports submitted through a consent process may be reviewed as part of that process.
How can I get geotechnical advice for my property?
If you would like more certainty about a particular site, you can engage an independent geotechnical professional to undertake an assessment. A site-specific report showing low risk to prospective purchasers or insurers will usually provide more detailed and relevant information than regional mapping, even where the mapping flags an area of concern.
We’re also preparing a template letter of engagement to help homeowners obtain geotechnical advice, and a link will be added once it is available.
Where can I find more information?
If you’d like more information, you can read the methodology and full report on Knowledge Auckland or read our factsheet [PDF 25.7 MB]
You can also visit the main Auckland Council website for more information on the Landslide Susceptibility Study maps, and for information and advice on addressing or updating information that appears on a Land Information Memorandum (LIM) from Auckland Council.