Indicative wetland maps

The maps help to identify areas where wetlands are likely to occur, including sites that may be degraded or previously drained. They can:

• highlight priority areas for restoration 
• support projects such as fencing, planting, and weed control 
• help landowners access funding and advice.  

For farmers and landowners, the mapping can support freshwater farm plans, help identify wet or sensitive areas, and help inform fencing, planting, and stock management decisions.  

For councils, iwi, and communities, the maps can support catchment and landscape planning, biodiversity strategies, restoration priorities, nature-based solutions, and kaitaikitanga. 

In addition, the maps provide a baseline for tracking changes in wetlands over time, monitoring progress towards restoration, and informing funding decisions. They can help to protect native species by identifying potential habitat and supporting field surveys and targeted conservation work.

However, the indicative wetland maps will not be used for regulatory monitoring, enforcement, or to determine whether rules about wetland management apply. Although they provide a helpful indication of where wetlands are likely to be, the maps are not sufficient on their own for regulatory or legal decisions. Field assessment is required where decisions depend on whether a wetland is present.

The maps use a range of information to map wetlands efficiently across Taitokerau, including:

• high-quality aerial imagery 
• LiDAR (remote sensing technology that uses lasers to create 3D maps)
• predictive modelling and machine learning. 

Data from these sources are used together to predict where wetlands are likely to be and how extensive they may be. Using this technique, we have been able to identify over 100,000 potential wetlands, many of which were not previously recorded. The maps include small wetlands that have previously been underrepresented or unmapped, significantly improving understanding of wetland distribution.

The maps are best used as an indicative guide to where wetlands are likely to occur, rather than a definitive map.

They vary in accuracy depending on wetland type.

• Mangroves and saltmarsh are mapped with high accuracy (around 88%)
• Waterbodies have moderate accuracy (around 80%)
• Gumlands are moderately accurate (around 68%)
•  Freshwater wetlands are the most difficult to map, with around 54% confirmed as correct 

The variation in accuracy is because some types of wetlands are more difficult to detect, especially:

• wetlands in pasture, where vegetation looks similar to surrounding land
• wetlands under forest canopy, which cannot be seen from above
• small wetlands (<500 m²), where detail is limited
• gumlands, which can look similar to regenerating scrub

For more detail on the accuracy and reliability of the maps, read the independent quality assurance assessment. 

Quality assurance assessment of wetland mapping layers (PDF 1.83 MB)

You can view the indicative wetland maps online | Indicative wetland maps

The maps are made up of layers. Each layer is a single dataset shown over the base map. Each dataset, or layer, shows something specific – such as freshwater wetlands, mangroves, saltmarshes, or heathlands. For example, if you select the layer ‘Mangrove Extents (indicative)’ the map will show you an indicative display of where mangrove forests are located. 

There are two sets of layers in the wetland maps: Wetlands Pre-2024, and Indicative Wetlands.

Wetlands Pre-2024

These are Geographic Information System (GIS) layers developed and improved over several years up to 2024. They mostly came from converting Department of Conservation survey data into GIS maps and often include information about wetland type and ecology.

The Wetlands Pre-2024 set contains the following layers:

• Known wetlands: A combination of freshwater wetlands.
• Heathlands: Mapped gumlands and heathlands.
• Top 150 wetlands: The highest ranked wetlands from over 300 freshwater and estuarine wetlands across Northland. For more information, see: Ranking of top wetlands in the Northland region (PDF 1.53 MB) 
• Mangrove and saltmarsh area: A remote sensing method was used in 2020 to map saltmarsh and mangrove habitat in Northland. For the method, see: Northland intertidal vegetation mapping methodology (PDF 1.48 MB). For estuary/harbour reports, see: Resource library – Research and reports – Saltmarsh and mangroves. This mapping includes some errors – some non-mangrove vegetation was included and some saltmarsh was excluded.
• Seagrass habitat: Marine habitat surveys have included mapping areas of seagrass. However, these are not regionwide.
• Biodiversity wetlands: For mapped wetland sites, symbols in this layer indicate the main wetland type. By clicking on the symbol, further information is displayed, e.g. the site name and description.

Indicative Wetlands

These are GIS layers produced from high resolution oblique imagery and remote sensing data to give indicative maps of different types of wetlands. They use aerial imagery to manually highlight areas that appear to be wetland and carry out further checks using GIS techniques. For more details, see: Wetland mapping in Northern New Zealand using LiDAR and machine learning (PDF 6.11 MB).

Northland Regional Council commissioned an independent quality assurance (QA) assessment to evaluate the accuracy, confidence, and limitations of the new maps. The assessment supports transparent communication about how reliable the maps are and provides guidance on appropriate uses.

Quality assurance assessment of wetland mapping layers (PDF 1.83 MB)

The Indicative Wetlands set contains the following layers: 

• Freshwater Wetlands 
  • Combined Freshwater Wetlands (indicative):  Includes swamps, bogs, fens, seepages, shallow water, marshes and wet modified grassland, but excludes mangroves, saltmarsh, waterbodies, and heathlands (including gumlands).
  • Heathland and Gumland Extents (indicative): Mapped gumlands and heathlands.
  • Waterbody Extents (indicative): Mapped open water including ponds, lakes, wetlands, dams etc.
  • Known Wetlands Not Mapped in Indicative Maps: Mapped freshwater wetlands that are missing from the indicative wetland mapping.
• Coastal Extents
  • Saltmarsh Extents (indicative): Mapped saltmarsh – should be viewed with pre-2024 layer.
  • Mangrove Extents (indicative): Mapping based on areas within the Intertidal Area where vegetation was over 50cm and covered more than 50% of the area. Should be viewed with pre-2024 layer.
  • Saltwater Extent (indicative): Landward extent of saltwater influence.
  • Intertidal Area (indicative): Areas established to capture all areas where saltmarsh or mangrove may grow.  

It is important to view both sets of map layers. This is because Wetlands Pre-2024 is based on older information and may miss some wetlands, particularly small ones, whereas Indicative Wetlands is based on more recent information and has far greater and more detailed coverage across the region, but is indicative only and does not have extra information such as ecology. 

The maps will not be used for regulatory monitoring, enforcement, or to determine whether rules about wetland management apply. 

However, you can use the maps as a starting point to help identify potential wetland areas. If further investigation, including field assessment, confirms the presence of a wetland, you may:

• be eligible for funding support for wetland protection 
• need to abide by national and regional rules managing activities that affect natural wetlands – these rules cover activities such as earthworks, vegetation clearance, drainage, stock access, and taking or diverting water. 

Find out more about funding support for wetland protection

Find out more about the rules affecting confirmed wetlands

The Tangata Whenua Māori Advisory Committee (now Te Ruarangi) and Māori Technical Advisory Group helped to shape the development and use of the wetland maps. Their input guided data accuracy and validation, appropriate use, public access to information, protection of sites of significance, and data sovereignty. 

The wetland mapping does not identify tāngata whenua cultural values or sites of significance associated with wetlands, and it does not replace iwi or hapū knowledge.

You are welcome to provide feedback or report possible errors. 

Before contacting us, please:

• check that the relevant wetland layers are turned on in the map
• click on the wetland feature to view available information
• review any notes about data limitations or accuracy

If you still need help, use the contact options below based on your query type.

If you believe a wetland is incorrectly mapped, missing, or misclassified, or if you have concerns about how the map information applies to your property, please include in your query:

• Property address or location
• Map screenshot (if possible)
• Description of the issue
• Any supporting information (e.g. reports, photos).