A free public layer of sub-regulatory overland flow paths, built on the latest LINZ 1 m LiDAR available for each region. The detail the National Flood Map doesn't resolve — for engineers, developers and councils screening sites.
Many New Zealand council flood maps are built on 2016 or older DEMs. Many don't model overland flow paths at all — only big rivers. The new National Flood Map stops at 256 floodplains and explicitly excludes property-level detail.
That's fine for public awareness. It isn't enough for early site screening or pre-purchase due diligence. FloodMap.nz publishes a consistent national overland flow path layer — streams down to 0.4 hectare catchments wherever LINZ has flown, derived from the latest LiDAR available for each region, at property-level resolution. It is a screening reference: it shows where water would route across bare terrain, not whether a given property floods, and any assessment of a specific property or project needs site-specific investigation. Free to view.
25 to 500 hectare catchments. Catchment-scale orientation and early screening at subdivision scale.
2 to 25 hectare catchments. Early subdivision layout screening, before detailed design and assessment.
0.4 to 2 hectare catchments. Fine-scale screening to flag sites that warrant site-specific assessment.
Surface flow paths that may not appear in council mapping built on older LiDAR. Useful for site walks, lot layout and rational-method sanity checks.
For engineers →See early whether overland flow paths cross a site, so due diligence can focus where it matters. Free to view.
For developers →Nationwide overland flow paths your team can compare against existing council mapping. Sources and limitations published.
For councils →See where flow paths constrain building platforms before you finalise layouts or lodge an application.
Open the map →Free public reference for pre-event briefings and public communications. Documented sources and limitations.
Read the methodology →See where overland flow paths cross or pass close to a property. No login, no cost, no quota.
Open the map →The government National Flood Map and council viewers are public awareness tools. FloodMap.nz is the fine-scale overland flow path overlay that complements them.
| FloodMap.nz | ESNZ National Viewer | Council GIS | MfE National Flood Map (2027) | |
|---|---|---|---|---|
| National coverage | All 16 regions, wherever LINZ has flown | 256 floodplains | Single district or region | Expected 2027 |
| Detail down to 0.4 ha catchments | Yes | Not at this scale | Varies by council | Scope not yet published |
| Built on the latest LINZ survey | Yes | Varies | Varies by council | Varies |
| Overland flow paths (0.4 ha+) | Yes | Not published | Varies by council | Scope not yet published |
| Free public access | Yes | Yes | Yes | Yes |
| Published sources & limitations | Yes | Partial | Varies | Not yet published |
Every layer is derived from the latest LiDAR available for each region, with sources and limitations published, and aligned with the standards councils use.
No. ESNZ's viewer is a public awareness tool covering 256 major floodplains at street level — explicitly not for property-level risk assessment. FloodMap.nz covers every stream down to 0.4ha catchment, at property-level resolution, on newer LiDAR. Different scale, different purpose.
No. MfE's 2027 product is an aggregator — it stitches together what each council already has. Where councils have detailed models, MfE will surface them; where they don't, MfE won't fill the gap. FloodMap.nz builds a consistent national model from the DEM up.
The methodology is aligned with TP108, SWCoP v4, and NZS4404. Individual councils make their own call on what data they accept for consent. The free layer is a screening reference, not a regulatory hazard map — for site-specific consent submissions, that's an engineering job done on commission.
The current published layer focuses on rainfall-driven overland flow. Coastal storm surge and sea-level rise are not modelled. For coastal hazard, we recommend the NIWA / Earth Sciences NZ Extreme Coastal Flood Maps.
The layer is reissued as new LINZ LiDAR survey blocks are published. Affected regions are reprocessed against the latest composite.
The free public map is view-only. Data exports and API access for engineers and councils are under development — register interest via the contact form.
Yes — through SAE Ltd. Site-specific HEC-RAS 2D flood assessments (depth, velocity, hazard, before/after earthworks) are scoped per site as bespoke engineering. See /flood-report for what's typically covered, or get in touch.
Free to view. Search any NZ address. No login.