‘Calamity of compounding errors’ cuts off environmental flows in Murray-Darling Basin
In what has been described by one regulator as a “potential calamity of monumental, multiple, compounding errors”, state and federal authorities may have inadvertently stolen or misallocated water throughout the Murray-Darling system, leading the suspension of crucial environmental flows across the basin.
The world-famous Macquarie Marshes depend on closely managed environmental flows.Credit: Nick Moir
The suspension comes after a dispute between irrigators and the two government bodies that hold and release water for the environment – the Commonwealth Environmental Water Holder, and a similar state body housed in the NSW Environment Department – over the extraction of water at Toorale station, a former cropping and grazing operation that is now a national park in the state’s far west.
The environmental impact of cutting off environmental flows could be catastrophic, particularly at this time of year, said Professor Jamie Pittock, a flooding and climate change expert at Australian National University. Over the coming weeks the environmental water holders would begin to release water to mimic spring snowmelt, signalling spawning season to native fish, he said.
During wet years, like this one, they would be seeking to push water into wetlands that are harder to reach and so are infrequently watered. There they sustain not only black box and coolibah floodplain forests, but protect the birds that nest within them from predators.
“For most of those bird species, the chicks will die unless the water level remains constantly under that vegetation,” he said.
The last wheat harvest at Toorale Station in 2008 before it became a National Park.Credit: Michelle Mossop
“[The floodplain forests] rely on this for the resilience they will need to survive the dry years that will inevitably come,” he said. “As a result of the suspension of environmental flows, these ecosystems might now face drought conditions in the midst of a wet year.”
A flow to the Macquarie Marshes floodplain was to begin in the coming fortnight to help build on the resilience of wetland vegetation following the 2019 drought, and support native fish breeding opportunities in the Macquarie/Wambuul River, said Mel Gray, a water campaigner for Nature Conservation Council NSW.
Troy Grant, the federal inspector-general of water compliance and former NSW police minister, said irrigators have been complaining that the environmental water holders had not been complying with water laws and regulations at Toorale, which lies at the junction of the Darling and Warrego Rivers west of Burke.
Grant said that similarly to equipment used in agriculture, infrastructure used at Toorale to extract water from the rivers and divert it into the national park is “constructed, licensed, operated, and utilised by different bodies at state and federal level, and each of them may well have contributed to the potential illegal take of water or over-extraction of environmental water.”
He said it was possible that laws and regulations had been broken in the over-extraction of water, the unlicensed extraction of water, the unmetered extraction of water, and in the inappropriate construction of works to take the water.
It was possible that similar errors had been made at other extraction sites across the Murray-Darling Basin, which sprawls over a million square kilometres, he said.
He said did not believe any laws were deliberately broken, but that various bodies over many years operating in a complex system may have made mistakes.
It was a “potential calamity of monumental, multiple, compounding errors.”
Grant said after the complaints were made the Commonwealth Water Holder “acted professionally” by suspending its contribution to NSW environmental water flows. The NSW environmental water holder has also suspended environmental flows.
The Commonwealth Environment Water Holder, Dr Simon Banks, said in a statement that he had “temporarily paused all environmental watering actions in NSW … due to a recent shift in how held environmental water is interpreted under various NSW water-sharing and policy frameworks.”
The NSW environmental water holder took similar action. “Environmental water holders, in an abundance of caution, have suspended delivery of some environmental water in order to ensure they remain within the law,” said a spokesperson for the NSW Department of Climate Change, Energy, the Environment and Water.
“We have discovered a technical issue in the way the NSW Water Management Act is drafted which we are working to resolve.”
In a separate statement, the department said the government was taking steps to ensure all water is effectively and transparently accounted for and that not all environmental water delivery has stopped.
“Some events can still be delivered this year as planned where this can be done within the current rules. Rainfall and other water releases from dams also mean water will continue to flow in rivers.
“The impacts of missed environmental water deliveries will vary according to the valley and specific environmental requirements.
“We are working closely with multiple agencies and government partners to address the concerns raised by the Commonwealth Environmental Water Holder and expect paused environmental water deliveries will be progressively reinstated throughout the water year.”
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