NZ Topo 50 Data Data

This dataset defines the Mean High Water coastline of New Zealand and offshore islands at a scale of 1:50,000, and describes the type of coast along the coastline, for example, steep coast, mangrove, or stony shore.

Purpose
The NZ Coastline – Mean High Water dataset is the first step towards improving the national coastline data for New Zealand. LINZ is currently working on a long-term project, “Coastal Mapping” to capture a range of national coastlines derived from LiDAR and bathymetry. This will enable us to generate coastlines, for example, for Mean High Water Springs, Chart Datum and Highest Astronomical Tide. The project is currently focused on capturing LiDAR and bathymetry data, and the timeframe for delivering the new coastlines will be established once the data capture has progressed.

Status
This dataset was created from LINZ Hydrographic and Topographic sources in August 2020 and will not be maintained in this form. This dataset will be replaced by a more accurate dataset in the future once data becomes available through the Coastal Mapping project.

Data sources and preparation
The spatial coastline data (1:50,000 scale) is sourced from the Topo50 series where it is described as a line forming the boundary between the land and sea, defined by mean high water. The source polygon data has been broken up into line segments to enable a coastal classification to be attributed to each segment of coast. Coastal classification data is based on official Electronic Navigational Charts published by the New Zealand Hydrographic Authority. Not all segments have been assigned a coastal category.

APIs and web services
This dataset is available via ArcGIS Online and ArcGIS REST services, as well as our standard APIs.
LDS APIs and OGC web services
ArcGIS Online map services
ArcGIS REST API

This provides a polygon coastline and islands layer which is based on the Topo50 products. It is a combination of the following layers:

• NZ Coastlines (Topo 1:50k)
• NZ Island Polygons (Topo 1:50k)
• NZ Auckland Is Island Polygons (Topo, 1:50k)
• NZ Campbell Is / Motu Ihupuku Island Polygons (Topo, 1:50k)
• NZ Antipodes Is Island Polygons (Topo, 1:25k)
• NZ Kermadec Is Island Polygons (Topo, 1:25k)
• NZ Bounty Is Island Polygons (Topo, 1:25k)
• NZ Snares Is / Tini Heke Island Polygons (Topo, 1:25k)
• NZ Chatham Is island polygons (Topo, 1:50k)

This topographic coastline is the line forming the boundary between the land and sea, defined by mean high water.

Islands from the NZ Island Polygons layer that lie within the NZ Coastline and Chatham Islands areas (i.e. islands in lakes, rivers and estuaries) have been removed.

The GIS workflow to create the layer is:

1. NZ Coastlines were converted from a polyline to a polygon using a polyline to polygon tool.
2. The resulting coastal polygon was then used as an input into an erase tool and run against the NZ Island Polygon layer to remove all islands lying within the NZ Mainland and Stewart Island.
3. This was then merged with the NZ Chatham Is island polygons (Topo, 1:50k) that have had the islands within the main island polygon removed, NZ Auckland Is Island Polygons (Topo, 1:50k), NZ Campbell Is / Motu Ihupuku Island, NZ Antipodes Is Island Polygons (Topo, 1:25k), NZ Kermadec Is Island Polygons (Topo, 1:25k), NZ Bounty Is Island Polygons (Topo, 1:25k) and NZ Snares Is / Tini Heke Island Polygons (Topo, 1:25k) layers using a merge tool.
4. Lake Onoke from the NZ Lake Polygons (Topo 1:50k) layer and Te Whanga Lagoon from the NZ Chatham Is lagoon polygons (Topo, 1:50k) layer were then erased from the resultant polygon layer to include these two water bodies in the coastline definition.

For more detailed description of each layer refer to the layer urls above.

APIs and web services
This dataset is available via ArcGIS Online and ArcGIS REST services, as well as our standard APIs.
LDS APIs and OGC web services
ArcGIS Online map services
ArcGIS REST API

a sudden descent of water over a step or ledge in the bed of a river.

Data Dictionary for waterfall_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-w...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

The point at which a river or stream percolates into or through the soil.

Data Dictionary for soakhole_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-s...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

Low point or opening between hills or mountains

Data Dictionary for saddle_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-s...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

An isolated rock formation that constitutes a prominent or unusual landmark

Data Dictionary for rock_outcrop_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-r...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

A steel tower supporting high tension wires

Data Dictionary for pylon_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-p...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

A structure that may be swung, drawn or lowered to block an entrance or passageway

Data Dictionary for gate_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-g...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

A relatively permanent walled and roofed construction.

Data Dictionary for building_pnt: docs.topo.linz.govt.nz/data-dictionary/tdd-class-b...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50

A structure on top of a hill, usually coloured black and white, used as a physical reference point by surveyors to determine location. The symbol shown on the map includes the elevation and trig identification code for beaconed trig stations.
These topographic trig points are derived from New Zealand geodetic marks data which can also be accessed through the LINZ Data Service: NZ Geodetic Marks and NZ Geodetic Vertical Marks.

Data Dictionary for trig_pnt: apps.linz.govt.nz/topo-data-dictionary/index.aspx?...

This layer is a component of the Topo50 map series. The Topo50 map series provides topographic mapping for the New Zealand mainland, Chatham and New Zealand's offshore islands, at 1:50,000 scale.

Further information on Topo50:
www.linz.govt.nz/topography/topo-maps/topo50