Independent Election Services

Representation Review Planner

Select a council

Population and modelling notes

  • Population data in this build is as at 30 June 2025.
  • Current general wards/constituencies use GEP and Māori wards/constituencies use MEP.
  • Where Māori representation is retained, the Scenario Modeller includes a Māori/general member calculator using MEP, GEP and the proposed total membership, then models the individual general and Māori wards/constituencies separately.
  • For Māori ward/constituency removal scenarios, the app uses total population inside the existing general boundaries.
  • The Map tab uses the supplied 2026 Ward and Constituency GeoJSON for general boundaries. Māori boundaries use the supplied Māori ward file, supplemented where necessary by the 2026 meshblock and geographic-areas files.
  • The Meshblocks toggle loads only the meshblocks for the selected council. Meshblocks are linked to their 2026 ward/constituency names using the supplied geographic-areas table. Their population values are 2023 Census electoral population on 2026 meshblock areas.
  • Meshblock boundary editing is available for total-population removal scenarios and for councils retaining Māori representation. Retained-Māori councils are edited separately on the General and Māori layers, using meshblock-level GEP and MEP respectively as planning inputs.
  • For retained-Māori boundary planning, ordinary meshblock moves start from the loaded 30 June 2025 GEP/MEP area totals and apply moved-meshblock 2023 Census GEP/MEP as planning deltas. If wards/constituencies are added, removed, merged or split, the proposed layer instead uses meshblock-level GEP/MEP directly because no loaded area total exists for the new geography. Source values of -999 are displayed as “less than 6” and are not assigned a guessed number. Preferred scenarios should be sent to Stats NZ for precise proposed-area populations.
  • Boundary editing also supports adding, removing, merging and splitting wards/constituencies. Split uses the currently selected meshblocks; merge combines member numbers by default; remove dissolves the area into another selected area and removes its members unless they are reallocated manually afterwards.
  • Community boards (and Auckland local boards) use the loaded 30 June 2025 total population and elected-member counts. There is no ±10% population/member test between separate boards.
  • Where a community or local board is subdivided, the ±10% population/member test is calculated within that board only, comparing that board's subdivisions with one another. Subdivisions belonging to different boards are never included in the same quota.
  • The Map and Scenario Modeller include separate Community/Local Board and Subdivision layers where those arrangements exist. Meshblock boundary planning on those layers uses 2023 Census total population on 2026 meshblock areas. If a meshblock is moved into a subdivided board, it must also be allocated to one of that board's subdivisions before the subdivision result is complete.
  • Community board and subdivision geometry comes from the supplied 2026 Community Board and Subdivision datasets and is linked to the existing 2026 meshblock crosswalk.
  • The next population dataset is the 30 June 2026 estimates, expected in October 2026.

Source workbooks are listed in data/councils.json. This is an internal working tool.

Representation Review Planner

Help

Views

Current arrangement shows the loaded existing representation arrangement. Map is used to inspect and edit boundaries. Scenario modeller is used to change member numbers and review the resulting population/member ratios and deviations.

Member allocation

Use the − and + controls in the Scenario modeller to change the number of members assigned to each ward or constituency. Quotas, population/member ratios and deviations update automatically.

Editing boundaries

On the Map tab, switch to Scenario and choose Edit boundaries. Select meshblocks, choose the destination area using the dropdown or by clicking an area label, then use Move selected. Undo and reset controls are available while editing.

Adding, removing, merging or splitting areas

While boundary editing is active, open Ward structure or Constituency structure. You can add an empty area, split selected meshblocks into a new area, merge two areas, or remove an area by transferring its meshblocks elsewhere.

General and Māori representation

Where Māori representation is retained, General and Māori boundaries are modelled separately. General areas use GEP and Māori areas use MEP. Meshblock-level electoral population is used as a planning input for boundary changes. Values recorded as less than 6 are not assigned a guessed number.

Community boards and subdivisions

There is no ±10% population/member test between separate community or local boards. Where a board is subdivided, the ±10% test is calculated only between subdivisions within that board. A meshblock moved into a subdivided board must also be assigned to one of that board's subdivisions before the subdivision result is complete.

Population data

The main representation calculations use the loaded 30 June 2025 population estimates. Boundary planning uses 2023 Census electoral population on 2026 meshblock areas. These meshblock figures are planning inputs and may not exactly match the area-level estimates.

Import and export

Export scenario creates a named, printable scenario report and includes the scenario data needed to reopen it later. Import scenario restores a previously exported scenario, including member allocations and saved meshblock assignments.

Offline use

The planner's code, council data, boundaries and meshblock files are packaged locally. If the internet connection is lost, calculations, scenarios, boundary editing, import/export and local map geometry continue to work. Online basemaps may disappear if a provider or internet connection is unavailable. Use the Basemap control on the Map tab to switch between OpenStreetMap, Esri Street, OpenTopoMap, Esri satellite imagery, or No basemap. The boundary geometry and editing tools remain fully functional without a basemap; when hosted over HTTP(S), the app also caches its own files for offline refreshes after the first successful load.

Map display

Green boundaries indicate areas within ±10%; red boundaries indicate areas outside ±10%. Reassigned meshblocks are highlighted while editing and are shown with diagonal hatching in exported maps. Meshblocks without geometry remain in population totals but cannot be displayed or moved spatially.

Planning limitation

The boundary modeller is intended for developing and comparing scenarios. For a preferred proposal involving GEP or MEP boundary changes, export the meshblock lists and obtain precise proposed-area populations from Stats NZ before relying on the final compliance result.