Surveyor’s sights set high after grant success

ON THE UP: Bathurst geodetic surveyor Nicholas Gowans will head overseas to discuss geographic height measurements after being awarded a grant. Photo: PHIL BLATCH 013018pbnick3
ON THE UP: Bathurst geodetic surveyor Nicholas Gowans will head overseas to discuss geographic height measurements after being awarded a grant. Photo: PHIL BLATCH 013018pbnick3

THE sky is the limit for Bathurst geodetic surveyor Nicholas Gowans as he prepares to head overseas to discuss a new way to record geographic height in Australia with international experts.

Mr Gowans will head to New Zealand, Canada and the US to learn about modern geographic height measurements, known as vertical datums, based on gravity models, and determine whether this is an option for Australia.

The opportunity comes after Mr Gowans was recently named the winner of the 2018 NSW Surveyor General International Fellowship Program, which awards a $15,000 grant for an international development and research opportunity.

“This is an opportunity to investigate how other countries have recently updated their vertical datums, and how Australia might benefit from a similar strategy,” Mr Gowans said.

For close to 50 years, national heights have referred to the Australian Height Datum (AHD), which is currently based on levelling measurements linked to tide gauges across Australia.

A vertical datum provides a common “zero-point” on which to base heights, allowing infrastructure, engineering and scientific projects to accurately model the flow of water.

Mr Gowans’ research will investigate if a combination of GPS positioning and gravity models would provide a more efficient solution to the current method, which is timely and costly.

“My study will look at whether Australia is better served by a vertical datum produced by levelling measurements, or by a new style using a gravity model,” he said.

The research is part of Mr Gowans’ PhD project, which he will complete part-time over six years.

Through Mr Gowans’ work at Spatial Services he has contributed towards a national effort to improve Australia’s horizontal datum, the Geocentric Datum of Australia.

“We’ve sorted the latitudes and longitudes, now we’re going after the heights above sea level,” he said.

The Geocentric Datum of Australia was updated last year and found Australia had close to two metres of movement since 1994 when it was last updated, meaning the Australian tectonic plate is moving seven centimetres each year north-east.

NSW Surveyor General Narelle Underwood congratulated Mr Gowans on his grant.

“The outcomes of his research could lead to improved surveying Australia-wide that is not only more accurate and cost effective but could also see enhanced mapping products for the public,” Ms Underwood said.