The next phase of work to update & enhance the NZ vertical datum 2009 began on Saturday with flights from Timaru to collect South Island aerial gravity data.
The vertical datum provides a consistent reference point for measuring heights in New Zealand, its offshore islands & the continental shelf. Collection of aerial gravity data to improve accuracy began last year, when Land Information NZ, along with GNS Science and Victoria University, gathered airborne data from most of the North Island. More North Island flights will take place this year.
The project marks the first time airborne gravity data has been collected on such a scale in New Zealand. Land Information Minister Maurice Williamson said an accurate national vertical datum was essential to ensure the accurate integration of geospatial data and the determination of global change, such as rises in sea level.
“An updated datum allows the construction & infrastructure industries to use GPS receivers to more accurately calculate the height of any location. This is used for planning water & sewage infrastructure that follows downhill inclines.
“Once the data has been collected, the results will be analysed in preparation for the release of an improved datum in 2016. It will be accurate to within 3cm in developed areas.”
Link: LINZ, vertical datum
Attribution: Ministerial & LINZ releases.