Hydrography Layers

A natural, flowing body of water emptying into an ocean, lake or other body of water and usually fed along it's course by converging tributaries.

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

A man-made water channel, often running parallel to the contours, built specifically for the distribution of water to crops, pasture, mining activities etc

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

A natural, flowing body of water emptying into an ocean, lake or other body of water and usually fed along it's course by converging tributaries.

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

An artificial open waterway used for transportation, waterpower or irrigation.

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

An isolated rock or rock formation between high and low tides.

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

Any standing body of fresh inland water.

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

The line forming the boundary between the land and sea, defined by mean high water.

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

Area of dry or relatively dry land surrounded by water or low wetland

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

An area of shallow water with walls or banks created for a specific purpose

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

This layer is a component of the Topo250 map series. The Topo250 map series provides topographic mapping for the New Zealand mainland and Chatham Islands, at 1:250,000 scale.

Further information on Topo250: www.linz.govt.nz/topography/topo-maps/topo250

This provides a polygon coastline and islands layer which is based on the Topo250 products. It is a combination of the following layers:

• NZ Mainland coastlines (Topo, 1:250k)
• NZ Mainland island polygons (Topo, 1:250k)
• NZ Chatham Is island polygons (Topo, 1:250k)

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, 1:250k) that have had the islands within the main island polygon removed using a merge tool.
4. Lake Onoke from the NZ Mainland lake polygons (Topo, 1:250k) layer and Te Whanga Lagoon from the NZ Chatham Is lagoon polygons (Topo, 1:250k) 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.