Summer services update
Information Summer services update

Our offices and services will have reduced availability over the holiday period.  Read more about our holiday hours and services availability.

Cadastral Vertical Control Network

The CVN provides the street-level control marks that are used by surveyors to connect cadastral surveys to the official vertical datum (NZVD2016).

Most cadastral surveys do not include heighted boundaries, of those that do many will be defined as ‘permanent structure boundaries” which do not need to be in terms of an official vertical datum. CVN marks will primarily be required in urban areas where multi-level developments are occurring or are likely to occur. The following page summarises the main characteristics of the network.

Purpose

To provide marks to enable cadastral surveyors to efficiently connect to the official vertical datum

Density

 

Across North Island, South Island, Stewart Island/Rakiura

Sufficient to enable surveys to be connected to official datums

Accuracy

Order: 5 (vertical only), 3V
Tier: F (0.35 m)
Class: IX (0.02 m, 1x10-4m/m)
Class evaluation radius: 0.3 km (urban), 1 km (rural)

Mark characteristics

 

Campaign GNSS

Conventional observations

Precise levelling

Location

 

Sited so that surveyors can easily and safely locate and occupy

Suitable for collecting GNSS observations

Mark access

Physical access to marks to collect GNSS observations

Visible from afar to enable conventional observations