Ashburton District Layers

Orthophotography for the Canterbury region taken in the flying season (summer period) 2012 - 2013. Coverage encompassed the Selwyn, Ashurbution, and Timaru council areas.

Imagery was captured for the ‘Environment Canterbury’ by Aerial Surveys Ltd, Unit A1, 8 Saturn Place, Albany,0632, New Zealand.

Data comprises:
•1,456 x ortho-rectified RGBi GeoTIFF images in NZTM projection, tiled into the LINZ Standard 1:5,000 tile layout
•Tile layout in NZTM projection containing relevant information.

The supplied imagery is in terms of New Zealand Transverse Mercator (NZTM) map projection. The products are tiled into NZTopo50 1:5,000 tiles. Please refer to the supplied tile layout shape file for specific details, naming conventions, etc.

Imagery supplied as 40cm pixel resolution (0.4m GSD), 3-band (RGB) uncompressed GeoTIFF. The final spatial accuracy is +/-0.6m.

Index tiles for this dataset are available as layer Canterbury 0.4m Rural Aerial Photos Index Tiles (2012-2013)

This layer contains the DEM for LiDAR data from the Christchurch and Selwyn areas captured in 2015.
The DSM is available as layer Canterbury - Christchurch and Selwyn LiDAR 1m DSM (2015).
The index tiles are available as layer Canterbury - Christchurch and Selwyn LiDAR Index Tiles (2015).
The LAS point cloud and vendor project reports are available from OpenTopography.

Lidar was captured for Environment Canterbury Regional Council by AAM between 5 October and 7 November 2015. The datasets were generated by AAM and their subcontractors. The survey area includes Christchurch City and parts of the Selwyn district. Data management and distribution is by Toitū Te Whenua Land Information New Zealand.

Data comprises:
•DEM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout
•DSM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout
•Point cloud: las tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout

Planned pulse density is 4 pulses/square metre.

Vertical accuracy specification is +/- 0.20m (95%).

Horizontal accuracy specification is +/- 1.00m (95%).

Vertical datum is NZVD2016.

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 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 artificial open waterway used for transportation, waterpower or irrigation.

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

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 place where water issues from the ground naturally

Data Dictionary for spring_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

This layer contains the index tiles for LiDAR data from the Christchurch and Selwyn areas captured in 2015.
The DEM is available as layer Canterbury - Christchurch and Selwyn LiDAR 1m DEM (2015).
The DSM is available as layer Canterbury - Christchurch and Selwyn LiDAR 1m DSM (2015).
The LAS point cloud and vendor project reports are available from OpenTopography.

Lidar was captured for Environment Canterbury Regional Council by AAM between 5 October and 7 November 2015. The datasets were generated by AAM and their subcontractors. The survey area includes Christchurch City and parts of the Selwyn district. Data management and distribution is by Toitū Te Whenua Land Information New Zealand.

Data comprises:
•DEM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout
•DSM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout
•Point cloud: las tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout

Planned pulse density is 4 pulses/square metre.

Vertical accuracy specification is +/- 0.20m (95%).

Horizontal accuracy specification is +/- 1.00m (95%).

Vertical datum is NZVD2016.

A closed pressure system,usually constructed of steel or ferro concrete pipes.

Data Dictionary for pipeline_cl: 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

A pipe system comprising a rising leg and a falling leg, typically in the shape of an inverted U. Works on atmospheric pressure

Data Dictionary for siphon_poly: 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

The Canterbury region of New Zealand experienced a sequence of significant earthquakes during 2010 and 2011. These earthquakes occurred on 2010-09-04, 2011-02-22, 2011-06-13 and 2011-12-23. Precise-levelling surveys have been carried out throughout Canterbury and Christchurch to re-establish heights after these earthquakes.

Users may also be interested in the horizontal coordinates derived from GNSS data in the companion layers Canterbury Earthquake Geodetic Marks (2010, 2011) - Comprehensive and Canterbury Earthquake Geodetic Marks (2010, 2011) - Simple

Horizontal Accuracy (standard deviation) approx 1m.
Vertical Accuracy of Lyttelton Vertical Datum 1937 heights (standard deviation) 0.005m.

Heights generated from precise levelling data undertaken to a misclose standard (mm) of 5*sqrt(k) where k is the distance in kilometres. Precise levelling in the Christchurch area was undertaken after the 23 December 2011 earthquake. Other areas were levelled after the most recent earthquake to have affected heights in that area. Heights therefore represent the position of marks accounting for all four substantial Canterbury earthquakes.

These heights are only provisional. Analysis is ongoing as further data is collected.
Heights calculated using SNAP v2.3.64.
Heights were constrained using the pre-earthquake heights at geodetic codes AC9B, AFAQ, AG32 and B853. GNSS observations and modelling indicates that the height change of these marks was negligible.
Some heights were calculated from precise levelling data provided by Christchurch City Council.

These coordinates are suitable for use in surveys and other geospatial activities in Canterbury and Christchurch.

For further information about this dataset, see the Canterbury earthquake information on the LINZ website.

This layer contains the index tiles for LiDAR data from the Canterbury Region captured between November 2016 and January 2017.

• The DEM is available as layer Canterbury LiDAR 1m DEM (2016-2017).

• The DSM is available as layer Canterbury LiDAR 1m DSM (2016-2017).

• The LAS point cloud and vendor project reports are available from OpenTopography.

Lidar was captured for Environment Canterbury Regional Council by AAM New Zealand between November 2016 and January 2017. The datasets were generated by AAM New Zealand and their subcontractors. Data management and distribution is by Toitū Te Whenua Land Information New Zealand.

Data comprises:

• DEM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout

• DSM: tif or asc tiles in NZTM2000 projection, tiled into a 1:1,000 tile layout

• Point cloud: las tiles in NZTM2000 projection, tiled into a 1:2,000 tile layout

Pulse density is 3.44 pulses/square metre.

Vertical accuracy specification is +/- 0.20 m (95%).

Horizontal accuracy specification is +/- 1.00m (95%).

Vertical datum is NZVD2016.