The physical component of New Zealand's geodetic system is a network of control marks that serve as physical reference points. A number of these marks are black and white trig beacons, seen on the tops of hills, or steel pins set into concrete in urban areas.
These marks are used by surveyors to determine the location of property boundaries in relation to the official geodetic datum.
Protection & maintenance of survey marks
Thousands of vital survey marks exist in New Zealand. Many of them are below or at ground level and not noticed by most of us.
People involved in construction work are responsible for making sure survey marks are not damaged. When building works have the potential to destroy existing cadastral and geodetic marks, LINZ needs to be notified so that it can assess whether the marks should be reinstated or replaced. Find out more about looking after the national survey network.
If you notice a damaged survey mark, you can report it to LINZ by filling out a form on this website.
For more information, see Survey mark protection.
Search the geodetic database
You can search for geodetic marks to find out the coordinates (such as latitude and longitude) for any geodetic marks in New Zealand, including the offshore islands such as Chatham Island and the Ross Sea region of Antarctica.
The geodetic database provides information about:
- the type of mark
- its coordinate
- location diagram
- site photographs.
GPS in New Zealand
LINZ operates the PositioNZ network, which provides GPS observations for New Zealand.
Find out more about GPS in New Zealand.
Sea level data
LINZ collects data using sea level gauges at different locations in New Zealand. This will eventually form part of a national network for monitoring tsunamis.
We prepare tidal information from data provided by port companies, regional councils and the National Institute of Water & Atmospheric Research.