Authorities are using satellites to keep track of river flows in the northern Murray–Darling Basin in a bid to guard against water theft.

The Murray–Darling Basin Authority (MDBA) has used imagery provided by Geoscience Australia to track water flows in the Barwon and Darling River systems during a major release of water for the environment into northern rivers between April and June.

A report into the trial, which found satellite images provide an important line of evidence for compliance, has been published by the MDBA.

MDBA’s acting head of compliance Brent Williams said the satellite images, coupled with on-ground gauge data, kept a close watch over the water, where it was going, and changes to on-farm activities along the river.

“We’ve been looking to the sky to make sure we know what is happening on the ground,” Mr Williams said.

“Satellite technology has helped us have a detailed look over a large area, giving us a valuable new tool to ensure water is delivered to where it is needed and is not diverted for unauthorised use.

“We now know the technology works, in concert with other lines of evidence. We’ll now look at how to use it wholesale to strengthen monitoring and compliance across the Basin.”

The images were so detailed they could detect water in irrigation channels and on-farm storages as well as any changes to crops. Changes could be quickly noted, cross referenced with other data, and passed on for investigation if required.

“The satellite images were a great help to see exactly how the water behaved as it made its way down the Barwon and Darling rivers,” Mr Williams said.

“For example, we could monitor how the water moved through the surrounding landscape.

“But perhaps most importantly, we could quickly measure any major changes to private storages at a time when there was an embargo on any consumptive extractions.”

The trial found no major changes to farm dam or water storages or any sudden or unexpected changes to the flow itself during the watering event, signalling a low probability of any compliance issues.