# The waiting water

The district plan’s flood-hazard layers, 4,000 mapped areas covering 38,668 hectares before overlaps. The managed catchments are named for the waterway they belong to; the high-hazard core is the ground the plan expects to take water deep or fast; the ponding spots are where it sits; Te Waihora’s extent is drawn to the 2.74 m contour.

## The standings

- High flood hazard: 1,692 areas, 2,530 ha
- High hazard, residential overlay: 128 areas, 49 ha
- Avon River: 225 areas, 3,812 ha
- Lower Styx River: 948 areas, 3,506 ha
- Heathcote River: 222 areas, 3,425 ha
- Lake Ellesmere: 4 areas, 1,037 ha
- Halswell: 84 areas, 610 ha
- Dudley Creek: 22 areas, 595 ha
- Bells Creek: 525 areas, 508 ha
- Lake Forsyth: 1 area, 411 ha
- Avoca Heathcote Valley: 4 areas, 190 ha
- Southshore: 4 areas, 179 ha
- Sumner: 4 areas, 140 ha
- Lansdowne: 38 areas, 86 ha
- Moncks Redcliffs: 2 areas, 41 ha
- McCormacks Bay: 1 area, 21 ha
- Lower Styx River: 44 areas, 759 ha
- Hendersons Basin: 8 areas, 289 ha
- Cranford Basin: 7 areas, 143 ha
- Cashmere Stream Floodplain: 3 areas, 49 ha
- Cashmere-Worsleys: 32 areas, 42 ha
- Hoon Hay Valley: 1 area, 27 ha
- Te Waihora 2.74 m contour: 1 area, 20,219 ha

## The suburbs under the waiting water

By share of outline inside the high-hazard areas, a sampled join, so a sliver still counts.

- Brooklands: 39% high hazard, 52% managed, 12 ponding spots
- Southshore: 38% high hazard, 66% managed
- Bexley: 33% high hazard, 51% managed
- Burwood: 27% high hazard, 65% managed
- Ferrymead: 25% high hazard, 86% managed
- South New Brighton: 22% high hazard, 67% managed
- Ouruhia: 21% high hazard, 38% managed, 13 ponding spots
- Westmorland: 17% high hazard, 41% managed, 1 ponding spot
- Cracroft: 15% high hazard, 25% managed, 9 ponding spots
- New Brighton: 14% high hazard, 71% managed
- Hoon Hay: 12% high hazard, 43% managed, 9 ponding spots
- Spencerville: 12% high hazard, 76% managed, 1 ponding spot
- Avondale: 11% high hazard, 84% managed
- Coutts Island: 11% high hazard
- Moncks Bay: 11% high hazard, 34% managed

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Christchurch City Council open data, the DistrictPlanB service’s flood-hazard layers (flood management, high flood hazard, the residential overlay, ponding, and the Lake Ellesmere flood area), the operative plan’s flood map. A model’s answer, not a memory, the record of water that has actually come: https://www.chch.live/floods · a point’s own answer: https://www.chch.live/before · the sea’s reach: https://www.chch.live/tsunami. The files: https://www.chch.live/flood-hazard.json · https://www.chch.live/flood-hazard.geojson · by suburb: https://www.chch.live/suburb-floodhazard.json