Significant natural areas - FAQ

Frequently asked questions about significant natural areas.

What are significant natural areas?

Significant natural areas (SNAs) are areas of significant indigenous vegetation and significant habitats of indigenous fauna. They are large areas generally over 0.5 hectares (1.2 acres) in size.

Te Awarua-o-Porirua Harbour and catchment are both hugely significant to our people. Porirua City is known for its coastal environment, iconic landscapes, and areas of significant biodiversity value.

Porirua City was once extensively covered in kohekohe-tawa forest. Extensive clearance of this vegetation in the mid and late 1800s for timber and farming, and more recently for expansion of urban settlements, has left the city with only scattered remnants of this former cover. This loss of vegetation has contributed to water quality issues in the harbour. This pattern of biodiversity loss is an issue across the whole region and the country.

Much of Porirua’s natural vegetation remnants are on public land and are protected as parks or reserves. Some of the significant remnants are on private land which currently have no protection.

The Resource Management Act (RMA) lists the protection of “areas of significant indigenous vegetation and significant habitats of indigenous fauna” as a matter of national importance. These areas are commonly known as “significant natural areas” (SNAs) in District Plans.

Throughout New Zealand, management of natural areas happens at both the regional and district council level (outside conservation land managed by the Department of Conservation). Greater Wellington Regional Council is responsible for setting the overall policy for the region. They have a specific role in maintaining and enhancing ecosystems in fresh and coastal water. They also undertake pest management across the region.

Porirua City Council is responsible for land-based natural areas. The Regional Policy Statement 2013 requires us to identify significant areas of native biodiversity, and protect them through policies and rules in our district plan.

Councils are required to identify specific trees or groups of trees that require protection rather than relying on blanket tree protection rules for the whole city. For example, councils can no longer have rules such as ‘protect all native trees over five metres in height’.

Other district councils in the Wellington Region will also have to address these requirements in their district plans. For instance, Hutt City Council has recently started engaging with their community about significant natural areas – see their website for more information.

We have undertaken an ecological assessment of the entire city. This was carried out by Wildlands Ecological Consultants, who have extensive experience doing similar ecological assessments.

Under this assessment ecosystems are considered significant if they meet one or more of the following criteria set out in the Regional Policy Statement:

  • representativeness – have characteristic examples of the original ecosystem that are no longer commonplace
  • rarity – have biological or physical features that are scarce or threatened
  • diversity – have a natural diversity of ecology, species and physical features
  • ecological context – enhances connectivity between ecosystems or provides habitat for rare indigenous species.

Wildlands re-evaluated sites identified in previous assessments (including Boffa Miskell 2001, Blaschke 2011 and 2015). Wildlands also used research and datasets from sources including the Department of Conservation and Greater Wellington Regional Council. Recent aerial photography was also used.

There is a further step required to ground-truth some sites to confirm whether certain species are present, including birds and animals which move between sites. Site visits by an ecologist may be arranged to verify that features on your property qualify as a significant natural area.

For more information please see the below report. 

Wildlands Ecological Consultants (2018) Draft Assessment of Ecological Site Significance in Porirua City – Methodology

There has been a history of engagement relating to significant natural areas (previously known as ecological sites or significant urban vegetation) which dates back to 2001. In 2012, engagement on the first draft ecological sites policy was undertaken with letters sent to homeowners and many site visits undertaken during this time. 

There was a significant amount of feedback from landowners, particularly around the restrictions on what maintenance could be undertaken on properties. For example, under rules in the 2012 policy, residents would not have been allowed to do simple pruning without resource consent.  There were also questions about the ecological value and/or mapping of some sites.

Another change since 2012 was the Regional Policy Statement becoming operative with amended criteria around what makes a site significant. Following reassessment on 2013 criteria, the number of identified sites has been reduced from the original 274 sites to 222. Areas of lesser ecological value have been removed based on this change in criteria.  To protect smaller stands of trees that still provide ecological value, we are asking the public to nominate notable trees [add link].

We are now taking a simple district-wide, integrated approach. These changes will make this policy easier for land users to understand and comply with, as well as knowing there is support and advice available.

If you believe there is an error in the mapping or assessment of a significant natural area, please visit our online map of identified landscapes and significant natural areas.

You can use the comments function to advise us of any questions or comments you have on the extent of these areas, or of the values identified in the assessment.

This is your opportunity to have input and identify things that need further investigation by Council staff and our ecologists, as this stage is a “desk top” analysis of existing information which may not have been checked recently in the field.

If required, site visits by an ecologist may be arranged to verify that features on your property qualify as a significant natural area.

For further information, you can contact the District Plan team on 04 237 5089 or

If your property has been identified as containing or being part of a significant natural area, this may place some constraints on what you can and cannot do with vegetation on your property.

You will not need to get a resource consent in order to trim, prune or plant vegetation.

We are looking at allowing a level of vegetation clearance where it will:

  • protect buildings and people
  • protect network utilities such as power lines
  • enable conservation or recreation
  • sustain or promote the ecological health of the Significant Natural Area

Vegetation clearance other than the above will be discouraged, and you may need to apply for a resource consent to prove the environmental effects can be avoided, remedied or mitigated.

The above rules will be consulted on in October 2018 as part of the District Plan review. We encourage you to provide feedback on how you think biodiversity can best be managed in Porirua.

There are numerous organisations and funds that landowners can access to look after biodiversity on their property including:

Porirua City Council's Sievers Grove Nursery

The Council has a nursery where you can buy a wide variety of plants at wholesale prices. The plants are grown on site from locally sourced seed and cuttings. They can provide expert advice on what to plant on your property and how to care for it.

Our nursery is at 106 Sievers Grove in Porirua East and open from 8am to 3pm Monday to Friday. Visit our webpage or call (04) 237 6893 for more information.

Greater Wellington Regional Council

The Regional Council has a range of programmes to support landowners in managing the biodiversity on their land, including funding, guidance and land management advice. Visit their website to find out more.

They also have the following guides for free download including:

Predator free groups in Porirua

Porirua City Council provides financial support to neighbourhood pest-free groups. Find out how to get involved.

Department of Conservation

DoC has a range of programmes available as a part of the Government’s “Predator Free 2050” target, an ambitious goal to rid New Zealand of damaging introduced predators. Visit their website for advice and more information on funding.

Queen Elizabeth II National Trust

The QEII Trust helps private landowners in New Zealand protect habitats of threatened animal and plant species on private properties. They can provide advice on accessing legal protection, funding and practical management advice. Visit their website for more information.

If you believe there is an error in the mapping or assessment of a significant natural area, please visit our online map of identified landscapes and significant natural areas.

Enquiries can be made to  or contact us on 04 237 5089.

If you have further questions please contact us on 04 237 5089 or