Overview Aotearoa Research Science
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Compound earthquake-climate risk in Wellington

Wellington faces an unusual and severe compound hazard profile: high-probability major earthquake risk intersects with climate change impacts including sea-level rise, increased rainfall intensity, and coastal storm surge. These hazards interact: a major earthquake that subsides coastal land permanently increases sea-level-rise exposure; climate-driven flooding may be followed by earthquake-damaged drainage infrastructure.

Compound earthquake-climate risk in Wellington

Analysis horizon: 50yr · 100yr

Wellington Fault rupture probability

GNS Science estimates that the Wellington Fault has approximately an 8–11% probability of rupturing in the next 100 years, producing a Mw 7.4–7.9 earthquake directly beneath the city — one of the highest-probability major earthquake risks of any capital city in the world (claim.wellington.climate.wellington_fault_rupture_probability).

Compound hazard amplification

Wellington’s compound hazard profile — earthquake plus sea-level rise plus intensified storms — means that standard single-hazard risk assessments underestimate actual exposure. Infrastructure must be designed to function under combinations of hazards that were previously treated as independent (claim.wellington.climate.compound_hazard_infrastructure_risk).

Drivers

The following structural drivers contribute to this problem.

Earthquake-climate compound hazard interaction

  • Category: physical
  • Timescale: long
  • Consensus: consensus

Wellington Fault major earthquake hazard

  • Category: physical
  • Timescale: long
  • Consensus: consensus

Solution camps

A number of distinct positions recur in policy debates on this issue. Each is defensible on its own terms; none is obviously correct. Presented in alphabetical order without ranking.

Integrated Multi-Hazard Risk Planning

Wellington’s compound hazard profile (earthquake + climate) requires integrated risk planning that cross-references both hazard types in land use and infrastructure decisions.

Flagship moves:

  • Joint earthquake-climate adaptation planning unit across all Wellington TAs
  • Mandatory multi-hazard risk assessment for all major infrastructure consents
  • Scenario planning for earthquake + storm compound event with CDEM

Tensions:

  • Multi-hazard integration requires significant analytical capability not currently in most TAs
  • Comprehensive risk planning may paralyse decision-making in the short term

Interventions on the system:

  • Establish Wellington Multi-Hazard Planning Unit shared across GWRC and all TAs (state variable: integrated_hazard_planning_coverage, sign: +)

Precautionary Land Use Controls for Hazard Zones

Prohibiting new development in compound hazard zones (fault lines + flood plains + liquefaction) is the safest long-term approach.

Flagship moves:

  • Map all Wellington compound hazard zones in District Plans
  • Prohibition on new residential development in category 3 hazard zones
  • Incentive-based voluntary relocation from highest-risk existing residential areas

Tensions:

  • Development prohibitions may worsen housing supply in an already constrained market
  • Category boundaries are contested; property owners dispute zone classifications

Interventions on the system:

  • Require multi-hazard risk overlay in all Wellington District Plan reviews under RMA (state variable: development_in_hazard_zones, sign: -)

Claims cited on this page

  • GNS Science estimates the Wellington Fault has approximately an 8–11% probability of producing a Mw 7.4–7.9 earthquake in the next 100 years, representing one of the highest-probability major earthquake risks of any capital city globally. [value: 9 percent probability of Mw7.4+ rupture in 100 years (midpoint estimate); 2022] — Wellington Fault Earthquake Hazard Assessment.
  • Standard single-hazard risk assessments underestimate Wellington’s actual infrastructure exposure because earthquake and sea-level rise hazards interact: fault rupture can permanently subside coastal land, while infrastructure damaged by earthquake reduces climate resilience of the built environment. — Wellington Fault Earthquake Hazard Assessment; New Zealand Sea Level Rise Guidance: Updated Projections 2023.

Further reading

Technical notes

State variables: compound_hazard_exposure_index, fault_rupture_probability_100yr.

Constraints: urban_development_on_reclaimed_land, fault_zone_land_use_planning.

Inputs: fault_rupture_magnitude, sea_level_rise_trajectory.

Feedback loops:

  • Compound amplification: earthquake land subsidence permanently increases coastal flood exposure; infrastructure damaged by earthquake reduces climate resilience of the built environment.

Generated from problem.wellington.climate.compound_hazard_risk on 2026-06-11. Do not hand-edit. Edit the entity files under the region’s data/ directory and re-run the region’s render.py.