The NSW water watchdog is warning it can now see everything, thanks to unprecedented access to satellite imagery from agencies, including the European Space Agency, to crack down on illegal water take.
- New satellites imagery is being used to improve monitoring of water take
- The land area under investigation now includes 3,500 properties
- The regulator, NRAR, is so far happy with compliance
The imagery is being used by the Natural Resource Access Regulator (NRAR) to monitor water flows and water extraction in great detail, investigating on-farm storages and floodplain harvesting.
Chief regulatory officer Grant Barnes said it conducted the biggest monitoring effort in its history when watching an environmental flow in November travel down the Barwon-Darling River across 306,400 square kilometres and past more than 3,500 on-farm storages.
The technology was also used to monitor a flow in the Barwon-Darling in January, allowing NRAR to assess compliance and investigate on-farm storages in great detail.
“Satellite imagery is the most cost-efficient, effective and versatile tool we use for water compliance monitoring and investigations across the state.”
The results have so far been very positive, with one ongoing investigation into water compliance.
“Technology allows us to cover vast territory in a short order of time and the results were really positive,” Mr Barnes said.
“There were very high rates of compliance during the event, only a handful of sites were flagged for follow up and only one site has ongoing investigation now.”
The sophisticated technology means NRAR can use their resources and coordinate field staff more effectively.
“If there is an issue, officers are sent to investigate.
“We now do the same to monitor a rain event, we can tap into the technology whenever we’d like.”
Eyes in the sky
Mr Barnes explained the satellite images were so precise and clear, NRAR could zoom in to see details on individual trees.
“We use four satellite imagery providers — the European Space Agency’s Sentinel, the US Geological Survey’s Landsat, Google Earth for 3D imagery and commercial provider Planet,” he said.
“Landsat provides NRAR with the longest historic satellite record, with images that can be used to assess changes in the landscape over the past 40 years.
NRAR insisted the process was not intrusive and that landholder’s privacy was protected during the process.
“Water is a publicly owned resource — to access water, by way of licence or approval, confers obligations,” Mr Barnes said.
“We are respectful of people’s privacy while using satellites and look to protect a landholder’s identity.
“We do not release satellite images with information such as property ownership that could reveal the identity of a landholder.”
How does it work?
The water watchdog can access new satellite imagery within 24 hours of its capture.
“Every day, satellites capture images of the Earth, allowing us to map out areas of irrigated crops, assess changes in riverbanks and riparian vegetation, and to assess changes in farm dams and large reservoirs,” NRAR’s Spatial Information & Modelling Specialist, Ivars Reinfelds, said.
“Satellite imagery can measure the growth of on-farm storages over time. It works by measuring changes in the surface area and number of dams across the state.
“We cross-reference these changes with a property’s water entitlements and if we notice anything suspicious, we will commence further investigations.”
Various technologies are used to give the final assessment of water extraction and compliance.
“Although we can use satellite imagery to provide estimates of water volumes in rivers, dams and water bodies, we use them in collaboration with complementary technologies to increase accuracy,” Mr Reinfelds said.
“We also use echo sounders and drones to determine water volumes and capacities of dams that are under investigation.
“River flows are monitored by flow gauging stations, and these provide the best estimates of water volumes in our rivers.”
Data will be stored to create a thorough record of water movements.
“It has a proven record in improving our effectiveness in monitoring water take and controlled activities to ensure compliance with water rules and regulations at NRAR. This is invaluable to our work.”
Fast, frequent satellite imagery
Satellite imagery is collected from a number of different organisations, so the frequency of imagery capture does vary.
A Murray Darling Basin Authority spokesperson said, “the satellite imagery used by the MDBA is from the European Space Agency Sentinel-2 satellites, which visit the same area and take a fresh picture every five days.”
“They can see objects on the ground down to 10 by 10 metres in size.
“The imagery is free and publicly available and can be accessed within a day of it being captured by the satellite.”
This varies from the imagery available from another agency, Sentinel 2.
“Imagery from Sentinel 2 has 10-metre pixel resolution, with one pixel being roughly equivalent to the size of a house,” a Geoscience Australia spokesperson explained.
“Geoscience Australia and our program partners have access to this imagery within 24 hours of it being collected by the satellite, through publicly-available feeds.”
Irrigators react to new technology
So, how are irrigators and other farmers feeling about this massive increase in farm surveillance?
National Irrigators Council chief executive Isaac Jeffery said they welcomes increased surveillance and anyone found stealing water or taking water illegally should be punished with “the full force of the law”.
“They are stealing from the river, from the environment, from communities and from the First Nations people,” Mr Jeffery said.
Meanwhile, the NSW Irrigators Council chief executive, Claire Miller, said they welcomed anything that gives an “accurate and robust picture of what’s happening out there”.
“The vast majority of irrigators do the right thing, we can see the results of that where we have high compliance,” she said.
“It’s great to have this out there to catch the few people that are doing the wrong thing.”
Justin McClure, president of the Australian Floodplain Association and a property owner on the banks of the Darling River, is happy with the NRAR upgrade in surveillance.
“The AFA welcomes measurement of all water diversion,” he said.
“Comprehensive accurate measurement can only aid the return of equity to all communities and the environment in line with the hierarchy of water use spelled out in multiple water acts.”
This Article firstly Publish on www.abc.net.au