Rangitāne o Wairau coastal-risk mapping
Pattern: whānau knowledge and taonga context → mapped exposure → consequence functions → hazard/risk modelling → shared spatial outputs.
The 2024–2026 project documented in Te Ao Māori in Coastal Risk Assessments was co-developed by Te Rūnanga a Rangitāne o Wairau and Earth Sciences New Zealand around extreme coastal flooding and sea-level rise at Te Pokohiwi o Kupe and the wider Wairau area.
What makes the spatial method unusual
Conventional hazard analysis often begins with buildings/roads exposed to a modelled hazard. This project also needed to represent impacts to Rangitāne taonga and places in a way that could be used in quantitative RiskScape modelling without stripping the analysis down to generic asset replacement values.
The public StoryMap shows both social and technical workstreams feeding the model.
Step 1 — establish the research relationship
The project began with hui and co-developed a Mātauranga Māori Plan describing the gathering, use and protection of mātauranga shared by Rangitāne whānau.
For a GIS practitioner, the practical lesson is architectural: decisions about the information are part of designing the data flow, not something added after the database is built.
Step 2 — whānau interviews and historical flood impacts
Semi-structured interviews collected first-hand experiences of flood events and aspirations around Te Pokohiwi o Kupe and Wairau.
Those accounts were analysed as part of the consequence/risk method rather than reduced to map-point attributes.
Step 3 — taonga mapping
The project worked with Rangitāne to digitise areas they wanted included in the risk assessment, including publicly described categories such as wāhi tapu, urupā, buildings and assets.
A particularly useful method described in the StoryMap was using highlighted areas where that was sufficient for the model, rather than sharing more detailed mātauranga than the risk analysis required.
This demonstrates an important GIS principle: a model can sometimes work with a deliberately broader spatial representation.
Step 4 — hazard and exposure analysis
Hazard and taonga exposure data were processed in RiskScape. Public project diagrams show an initial exposure workflow linking inundation hazards with Rangitāne taonga, roads and buildings.
The project then developed consequence functions so the model could represent more than whether a polygon simply intersected a hazard extent.
Step 5 — other spatial techniques
The StoryMap also documents drone-based and ground-based GPR work investigating archaeological taonga at Te Pokohiwi o Kupe. These are specialist methods rather than ordinary GIS collection techniques, but they show how multiple sensing/evidence systems can contribute to one research question.
What another iwi/hapū hazard project can borrow
1. define the risk question with the people/place involved
2. determine what local/whānau evidence belongs in the analysis
3. decide the minimum spatial representation the model needs
4. keep detailed source knowledge separate where appropriate
5. document hazard scenario/date
6. expose the model chain: hazard → exposure → consequence → result
7. review outputs with the people whose information shaped the model
This is much stronger than taking a national hazard layer, overlaying cultural sites and counting intersections.
Useful MāoriGIS.nz connections
What the public case does not establish
The StoryMap does not make the project's underlying detailed mātauranga or taonga database public. MāoriGIS.nz therefore describes the published methodology and public examples only.
Primary source
Te Ao Māori in Coastal Risk Assessments, updated through the 2024–2026 Rangitāne/ESNZ project.
Last reviewed: 26 August 2026