Christchurch high flood-hazard check (Apify Actor)

Point or small-extent intersect against the Christchurch City Council DP Flood Hazard High layer (DPFloodHazardHigh, OpenData DistrictPlanB id 25). It GETs that one ArcGIS query endpoint and writes an allowlisted hit or miss. It does not page the layer.

This is a point or extent intersect, not a republish of the polygons. Geometry, shape area, shape length, and popup text are not requested and not emitted. There is no citywide extract.

Not endorsed by Christchurch City Council, DHI, or Environment Canterbury. The attribution line is the credit. It does not add an endorsement claim.

Data source called (default): https://gis.ccc.govt.nz/server/rest/services/OpenData/DistrictPlanB/MapServer/25

Research names that MapServer URL. The hub item URL for the same layer is FeatureServer/25, which is the URL inside the attribution string. source on each row is the layer URL this run actually calls (MapServer/25 unless the env override below selects FeatureServer/25).

There is no URL input. url, feedUrl, layerUrl, and outFields are ignored. A user where is never sent. A process environment override CCC_FLOOD_BASE_URL is accepted only when it is https://gis.ccc.govt.nz and the path is DistrictPlanB layer 25 (MapServer/25 or FeatureServer/25, optional /query). Any other host or layer is rejected.

Output fields

Each dataset item is an allowlist. SHAPE, Shape__Area, Shape__Length, PopupText, polygon rings, paths, and polygon coordinates are never emitted.

Field	Description
drvDPFloodHazardHighID	Layer object id, or null on a miss
CreatedByPlanChangeIdentifier	Plan-change create id, or null
RemovedByPlanChangeIdentifier	Plan-change remove id, or null
LegalStatus	Legal status, or null
DataSource	Organisation named on the feature, or null
ScheduleReference	Schedule reference, or null
CreateDate	Layer value as returned (ArcGIS epoch milliseconds, or null). Not reformatted.
LastEditDate	Layer value as returned (ArcGIS epoch milliseconds, or null). Not reformatted.
intersects	Hit/miss flag. True on every feature row when the point or extent intersects at least one polygon. A miss is a single row with intersects: false and null attributes.
source	The MapServer/25 or FeatureServer/25 URL actually called
attribution	Exact base line below. If DataSource is non-empty, a second sentence is appended: Data source: <DataSource>.

truncated is not a dataset field. It is true in the run log when the number of matching features is greater than maxItems (the extra match is requested so the cap can be detected, then dropped). One query is sent. The body cap is 8 MiB.

Inputs

Provide one of: a WGS84 point, an NZTM point, or a bounding box. A query with no spatial filter is rejected. where=1=1 (including spaced or parenthesised forms) without a point or extent is rejected. With a point or extent, the Actor still sends its own where=1=1 together with geometry, geometryType, inSR, and spatialRel=esriSpatialRelIntersects. That is an intersect, not a dump. returnGeometry=false. outFields is the eight attributes above, never *.

Input	Notes
latitude / longitude	WGS84 point. x is longitude, y is latitude, inSR 4326, geometryType=esriGeometryPoint. Always allowed.
easting / northing	NZTM2000 point (EPSG:2193), metres. inSR 2193. Always allowed. Easting must sit between 800000 and 3200000, northing between 4000000 and 7200000.
xmin / ymin / xmax / ymax	Envelope. geometryType=esriGeometryEnvelope.
inSR	Extent only. 4326 (default) or 2193.
maxItems	Default 10. Hard cap 50. Values above 50 fail the run. Research and compliance named no number.

Bounding box rule

Research and compliance did not name a maximum area or span. This Actor rejects an extent whose width or height is greater than 2000 metres. A box of exactly 2000 m on a side is allowed. A point is not limited by this rule.

• NZTM (2193): width = xmax - xmin, height = ymax - ymin, already in metres.
• WGS84 (4326): height = (ymax - ymin) * 111320 metres. Width = (xmax - xmin) * 111320 * |cos(mid-latitude)| metres, with mid-latitude in degrees. 111320 is the metres-per-degree constant used for this check, not a surveyed local grid.

xmax must be greater than xmin, and ymax greater than ymin.

A box inside that cap (not the default run):

{
  "xmin": 1570000,
  "ymin": 5180000,
  "xmax": 1570500,
  "ymax": 5180400,
  "inSR": 2193,
  "maxItems": 1
}

Try this

One Christchurch point, cap 1. A point is a single query. A run with no point and no extent is rejected.

{
  "latitude": -43.53,
  "longitude": 172.64,
  "maxItems": 1
}

Query shape

returnGeometry=false&outFields=drvDPFloodHazardHighID,CreatedByPlanChangeIdentifier,RemovedByPlanChangeIdentifier,LegalStatus,DataSource,ScheduleReference,CreateDate,LastEditDate&geometryType=esriGeometryPoint|esriGeometryEnvelope&inSR=4326|2193&spatialRel=esriSpatialRelIntersects&f=json

resultRecordCount is maxItems + 1 (at most 51). Non-JSON, non-200, an ArcGIS error object, and an unexpected shape fail the run. The Actor does not follow offsets.

A field-name probe on 3 Oct 2026 (PT) used returnGeometry=false, resultRecordCount=1, and the outFields allowlist. The raw body was not saved. Returned attribute names matched the allowlist. CreateDate was null on that row. LastEditDate was epoch milliseconds. DataSource was a string.

Attribution

Christchurch City Council — DP Flood Hazard High (OpenData), https://gis.ccc.govt.nz/server/rest/services/OpenData/DistrictPlanB/FeatureServer/25. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0): https://creativecommons.org/licenses/by/4.0/. This output is a point or extent intersect, not the original polygons; geometry, shape area, shape length, and popup text were not republished.

When a row has a non-empty DataSource, that same line is followed by one more sentence: Data source: <DataSource>. Empty or missing DataSource keeps the base line only.

Notes where the research and compliance docs were silent

• Neither doc named maxItems, a maximum box span, or the ArcGIS geometry / inSR parameter shape. This Actor uses the task rules: default 10, hard cap 50, box width and height at most 2000 m, intersect via ArcGIS query geometry + inSR.
• Research wins on the endpoint: the default call is MapServer/25. The required attribution string cites FeatureServer/25 (the hub item URL for the same layer). source records whichever of those two layer-25 URLs was called.
• Compliance's emit list did not include source. The task allowlist does, so each row includes it.
• Dates are passed through. They are not converted to Auckland calendar dates.

Known limits

• One layer only: DistrictPlanB id 25, DPFloodHazardHigh. No other DistrictPlanB family and no other host.
• A miss returns one intersects: false row so the hit/miss flag is always in the dataset.
• The 2000 m cap is a product limit, not a figure from the council service.
• NZTM range checks are a sanity bound for mainland NZTM2000, not a Christchurch clip.