What is happening?

From July 1st, 2024, Auckland Council will switch from Auckland Vertical Datum 1946 (AVD46) to New Zealand Vertical Datum 2016 (NZVD2016) as its official height (Z) datum standard.

Why change to New Zealand Vertical Datum 2016?

• NZVD2016 is a nationally consistent height reference, covering all of New Zealand. This ensures more accurate and consistent heights for regional and national projects.
• NZVD2016 heights are continuously updated to account for New Zealand's geological activity. In contrast, local vertical datums like AVD46, established nearly 80 years ago, have not been consistently maintained and are reaching the end of their usable life.
• New NZVD2016 height reference marks can be readily established whereas AVD46 marks, once moved or destroyed, cannot be reestablished, leading to potential reliability issues.

Who is affected?

Anyone who works with heights, level & elevations including:

What might this mean for you:

• Resource Consents and their associated documentation will need to be in NZVD16 from July 1st 2024 (unless an exemption from Council is granted),
• Existing Resource Consents may require a specialist report to detail the relationship between the existing data and NZVD16,
• Project time frame and costs may need to be reviewed to allow for a translation to be made to the project.

Translating from AVD46 to NZVD16

The height different between AVD46 and NZVD16 is not consistent across Auckland, it varies from approximately 250mm-360mm.

The translation may be simple (a uniform vertical shift) or complex (non-uniformly shifted using the LINZ sourced relationship grid).

The vertical translation needed will depend on various information including:

• The location (x,y co-ordinates),
• The extent of the site,
• The origin of levels (the specific control point the data is based upon) How the origin of levels was established (if the control point had a AVD46 level or was a level calculated based off the NZVD16 geoid)

Verification Process:

Before data is translated the following questions need to be asked:

• What co-ordinate system is the data in?
• What is the origin of co-ordinates?
• What vertical datum is the data in?
• What is the origin of levels?
• Where was the origin of level sourced OR how was the origin of levels established?

If these questions cannot be answered a more thorough investigation needs to be carried out which will likely include on-site verification.

Further assistance:

Should you require any assistance in understanding this process, or need help interpreting or translating data, please contact us,

or visit the following links for more information:

• From Auckland Council:  

www.aucklandcouncil.govt.nz/geospatial/Pages/adopting-official-height-standard-nzvd2016.aspx 

• On vertical datums: 

www.linz.govt.nz/guidance/geodetic-system/coordinate-systems-used-new-zealand/vertical-datums 

• On NZVD16:  

www.linz.govt.nz/guidance/geodetic-system/coordinate-systems-used-new-zealand/vertical-datums/new-zealand-vertical-datum-2016-nzvd2016