New Zealand Vertical Datum 2009 (NZVD2009)

The New Zealand Vertical Datum 2009 (NZVD2009) is the official vertical datum for New Zealand and its offshore islands. The datum is defined in relation to the NZGeoid09 geoid surface. Heights in terms of NZVD2009 are in the normal-orthometric height system.

The datum also defines offsets that enable heights to be transformed from the 13 existing major local vertical datums to NZVD2009 (and also NZGD2000 ellipsoidal heights if required).

The NZVD2009 datum covers the New Zealand continental shelf area between 160°E –170°W and 25°S – 60°S.

NZVD2009 is consistent with the NZGD2000 and hence the Global Positioning System (GPS) datum WGS84. This means that normal-orthometric NZVD2009 heights can be transformed to ellipsoidal NZGD2000/WGS84 heights and vice versa.

NZVD2009 is formally defined in the LINZ standard LINZS25004 (Standard for New Zealand Vertical Datum 2009). The key parameters from this standard are summarised below:

Name:	New Zealand Vertical Datum 2009
Abbreviation:	NZVD2009
Reference surface:	NZGeoid09
Height system :	Normal-orthometric
Normal gravity field :	GRS80