Flood hazard maps are generated by computer models that use the contours of the land, flow paths and infrastructure information to represent flood risks during intense rainfall.
View flood hazard maps
See where flooding is likely to occur in your neighbourhood by using our GIS mapping system, Mapi.
- Open Mapi and zoom in on the geographical area you wish to see. You can use either the +/- buttons or your mouse to zoom, or search for a specific address using the ‘find address’ button on the menu.
- Select ‘show layer list’ from the top menu.
- Scroll through the ‘layer’ options and select ‘natural hazards’ by ticking the box.
- Click on ‘natural hazards’ again to access the drop down menu. Select ‘flooding from rainfall’.
- Click on ‘show legend’ at the top of the map to see what the different flood hazard colours mean.
For more information on how to use Mapi, you can download our free user guide:
Mapi user guide (2.8mb pdf)
We use a system called LIDAR (Light Detection and Ranging) which measures the ground levels of the land using laser pulses. This generates an accurate contour map which we place into the stormwater computer model. LIDAR is very reliable technology used by most councils in New Zealand.
We then use a range of criteria to create our modelled maps. The sort of things we consider are:
- How hard is it raining?
- How long has it rained for?
- What is the contour of the ground?
- Where will rainwater soak into the ground (e.g. grass)?
- Where will rainwater flow over hard surfaces (e.g. roofs, concrete)?
- How long will it take for rainwater to flow from one part of the catchment to another?
- What stormwater systems are already in place?
The resulting models calculate how, when and where rainwater will flow and tells us which areas are likely to be covered by water and to what depth. Flooding less than 100mm isn’t shown.
When the modelling is complete, it’s reviewed to make sure it’s correct and uploaded into our GIS mapping system. The updated maps are sent to homeowners and kept on property files. Council has a legal obligation to make hazard information it holds available to the public. This information is therefore included in Land Information Memorandum (LIM) reports and used when reviewing building and resource consents. We will always provide the most up to date information that we have available about your property.
If you would like information on how this may affect your property value or insurance, we recommend you seek professional advice from a property valuer or insurance expert.
For more information on how to interpret the flood maps available in Mapi, how to request a review of mapped flooding on a property and the process involved, how to approach the development of land where mapped flooding is present as well as key contacts, and links to other relevant guidance and standards, please download this document:
Flood hazard modelling and mapping (1.2mb pdf)
Timeframe for flood hazard modelling updates
Area |
Indicative timeframe for updating |
Avenues/CBD/Gate Pā, Brookfield, Kōpūrererua, Pāpāmoa East/West |
2025 |
Mount Maunganui North, Waimapu, Wairoa |
2026 |
Kaitemako, Sherwood, Welcome Bay |
2027 |
Bethlehem, Greerton, Kōpūrererua, Pāpāmoa East/West |
2028 |
Waimapu, Wairoa, Matua |
2029 |
Kaitemako, Mount Maunganui Industrial, Mount Maunganui South, Pillans-Bureta, Welcome Bay |
2030 |