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 NZGeoid2009 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.

The accuracy of NZVD2009 heights is described by a series of Orders. Note that the Orders used for normal-orthometric heights are different to that used for ellipsoidal heights.

NZVD2009 is formally defined in the LINZ standard LINZS25004 (Standard for New Zealand Vertical Datum 2009) and is described in a 2010 paper published in New Zealand Surveyor (PDF 5.0KB). The key parameters from this standard are summarised below: