Aerial mapping will build deep knowledge of Southland water
15 November 2022
Aerial mapping will build deep knowledge of Southland water
The latest airborne technology is being used to understand more about Southland’s underground water resource and its links to our rivers and streams.
Environment Southland is assisting Aqua Intel Aotearoa on an airborne electromagnetic survey to find out more about the aquifers under northern Southland. Aqua Intel Aotearoa is a partnership between GNS Science and Kānoa, funded by Central Government’s Provincial Growth Fund.
A company called SkyTEM will be flying over the plains around the upper Oreti and Mataura rivers. The survey flights are scheduled to start in early November and are expected to take 5 weeks.
Environment Southland team leader - science, strategy and integration Ewen Rodway said the SkyTEM technology will enable them to look at our aquifers as far down as 300 metres, to see more detail than ever before.
“We will find out more about the characteristics and connections of our aquifers; including the connections to streams and wetlands. We will also learn more about the extent of our aquifers to help ensure the sustainable management of this precious resource.”
“You may see a low-flying helicopter towing a large loop suspended with cables. This sends electromagnetic signals underground, sensors measure the behaviour of the returning signals and this can tell us about the geology beneath the surface.”
Acting on local advice sought during preparations, the pilots will avoid flying over infrastructure such as towns and major roads, and they’re careful around stock. The technology has been proven safe around the world and has been used in Hawke’s Bay and Waikato. SkyTEM is currently using the technology to survey the Aupōuri aquifer in Northland.
The helicopter will fly at 80-120 kph in parallel lines generally 200 metres apart and at a height of approximately 100 metres. The measurement instruments are suspended under the helicopter and will be about 30 – 50 metres above the ground.
Aqua Intel Aotearoa programme director Jane Frances said the Government’s investment in this programme recognises that water resources are critical to Southland.
“This investment will provide high-quality science and data to help understand how water can be used to sustain people and develop land without undermining the health and wellbeing of the water, respecting Te Mana o Te Wai.”
This project is part of a wider GNS Science programme to map and characterise New Zealand’s aquifers, which will allow GNS Science to create advanced hydrogeological maps, methods and models to support sustainable and economic use of Aotearoa New Zealand’s groundwater resources.
The information gathered by the helicopter and loop will take some time to process and analyse. Once available, it will provide a much better picture of our underground water resources and reduce uncertainty to help guide decisions for environmental protection, development, resource consents, water management, and water availability for the local community.
