A royal commission into Australia’s arguably “worst” fishkill, which resulted in the deaths of millions of fish along the Darling-Baaka River in New South Wales (NSW), has been called on by the NSW Greens as investigators uncover missing crucial measurement equipment as a possible link to its causation.
Authorities estimate up to 20 million fish have died due to depleted oxygen levels in the river following prolonged flooding and repeated heatwaves in recent weeks. This incident has been reported to be worse than the one that occurred near the same location in 2018-2019 during a severe drought, where approximately one million fish were washed up dead.
“This is the worst fish kill on record, but unless we urgently shine a spotlight on the departments that continue to make the same mistakes over and over, it will just be the worst yet,” Faehrmann said.
“The NSW government has ignored scientific advice, manipulated water sharing plans, undermined environmental flows, allowed illegal pumping and meter tampering, and wasted hundreds of millions on ineffective infrastructure projects.
“This fish kill is just the latest in an extended ecological catastrophe caused by decades of mismanagement, incompetence and special treatment of irrigators’ interests by successive NSW governments and their agencies.”
The NSW government’s department of planning and environment has been approached for comment, but The Epoch Times was deferred to the NSW’s Public Information Functional Area Co-ordinator (PIFAC).
Meanwhile, federal water Minister Tanya Plibersek said the Menindee fish kill was devastating for the Menindee community and for the environment. She also criticised the Coalition for not delivering “anything” on the Murray-Darling Basin Plan for the past nine years, saying that were it otherwise, “we would be in a better place now.”
“I have recovered more water towards the additional environmental water target in nine months than you did in nine years,” she said on March 22 during question time in parliament.
Crucial Real-Time River Flow Data Taken Offline for Months
Water gauges along the Darling-Baaka River in the vicinity of Menindee lakes were taken offline in November 2022 due to significant flooding, WaterNSW—whose role it is to operate the lakes—told The Epoch Times in an emailed statement.As such, real-time river flow data was taken offline for months.
“The affected gauges needed to be recalibrated on-site to ensure accuracy before returning to service, a process that was delayed by the widespread flooding across the region, which restricted access to some sites,” a spokesperson for WaterNSW said.
However, the key monitoring gauge at Weir 32—which regulates river flow around the Menindee Lakes system—was only restored on March 13 after a million dead fish washed on the surface of the river.
The Murray-Darling Basin Authority told The Epoch Times that WaterNSW was able to reinstate the reliable flow at 13 March 2023 after hydrographers visited the site and the floodwaters receded.
Maryanne Slattery, a former director of the Murray-Darling Basin Authority, said the missing measurements from the gauge may have contributed to the fish kill.
“So the accusation is that the weir was closed, and the fish couldn’t escape the low-oxygen water; they were all looking to swim upstream.
“Now the data for all the direct measurements is all there on the website, but it doesn’t have the flow rate ... Sometimes you might have a broken gauge, or it didn’t upload, but it is really weird to have all the direct measurements but not the flow rate.”
Lack of Oxygen Leads to Massive Fishkill
Professor of Environmental Science at UNSW, Richard Kingsford told The Epoch Times in an email that because of the engineering structure at Menindee, the fish couldn’t move upstream.“The main reason (for the lack of oxygen) is because of the blackwater—where bacteria and other microbes break down the dead wood and branches in the river and floodplain, and then this went back into the main channel as the floodplain was drying along with the fish,” Kingsford said.
“Over many years, governments have allowed overallocation of the tributary rivers of the Darling River which means the flows are a lot less, and the small and medium floods that keep the river healthy have decreased.
“This means there is more dead wood on the floodplain, and so when there is a large flood like the 2022 one, then a lot more blackwater/or poor oxygenated water enters the river.”
However, in an email to The Epoch Times, a spokesperson for the emergency operation, NSW PIFAC, said it was not possible for the operations of Weir 32 to have caused the fish deaths.
“[Weir 32] is a fixed crest structure—literally a pile of rock. It has no ability to release water or to be opened or closed,” the spokesperson said.
“Weir 32 is also approximately 40 km downstream of the Menindee Weir pool. Most importantly, weir 32 has a fish passage structure to allow upstream migration of fish.”
Kingsford added that oxygen problems on the Murray River had existed previously but nothing to the extent seen recently.
“Many of the other inland rivers are healthy, and so fish can move up and down the rivers,” he said.
In response the oxygen problems, the spokesperson for the emergency operation said that both NSW and Commonwealth government agencies have been monitoring and taking actions to improve dissolved oxygen (DO) levels in the Murray Darling Basin since October last year when the risk of hypoxic blackwater was identified.
“This includes ensuring environmental water releases into the Darling River have the best chance of achieving better dissolved oxygen levels, to reduce the likelihood of further fish kills. However, there is still a large biomass of fish in the river, so there is still a high risk,” the spokesperson said.
“Increased releases of higher quality water from Lake Pamamaroo began flowing to the lower Darling Baaka River in late February as soon as our monitoring detected dissolved oxygen levels approaching those critical to fish health.
“Similar actions were taken to successfully navigate blackwater events in previous years since the drought ended.
“This work has helped to reduce the risk fish kills in other parts of the state; however, these mitigation options are limited, particularly in severe conditions.”
Kingsford said that water buybacks would help more environmental flows back into the river system but said that it would be very costly.
“There will be enough willing sellers for it to buy back water, but the water may be very expensive,” Kingsford said.
“We need to have more environmental flows in the river, the buyback will help to meet the target. We also need to understand how much water is going out at various times so we can manage the system to measure how much water there is at various times in the river.”
Clean Up Begins
Removal of the dead fish carcasses—many of the native bony herring, carp, Murray cod and golden perch varieties—began on March 23 evening after extensive delays in transporting heavy machinery from Sydney.The operation is being led by NSW Police. Specialist contractors have also been called in to help, while Fire and Rescue NSW officers were using booms to move the dead fish to shore for disposal.
NSW Police Assistant Commissioner Brett Greentree said it would take some time to remove the 20 million dead fish.
“It’s an unprecedented scale now and a logistical nightmare,” Greentree told ABC’s RN Breakfast on March 22.
“All I can say is it stinks,” he said. “You wake up through the night, and it is hard to get back to sleep because all you do is smell decaying fish.
“They are all rotten, they are all sinking, and when I turned my pump on yesterday, you could smell it through the water, through the hoses; it stinks, and I think it’s too late.”
NSW police have reassured local residents that their drinking water was safe.
Meanwhile, Barwon MP, Roy Butler, said he supports an independent investigation into the incident, reported The Guardian.
“I think there needs to be an independent investigation to look at what has actually happened and [to] get to the bottom of those causes because there are theories running around that it is other things,” he said.
“[We need to] get to the bottom of what really happened with an independent person and then come up with a series of recommendations if we can to try and avoid this happening again.”
