- Exclusive
- Environment
- Sustainability
- Water
'Treachery': Leaked report reveals low river flow blamed on extraction
The ailing state of the Darling River has been traced to man-made water extraction, according to a leaked report by the agency charged with overseeing its health.
The "hydrologic investigation", dated last November and obtained by Fairfax Media, analysed more than 2000 low-flow events from 1990-2017 on the Barwon-Darling River between Mungindi near the NSW-Queensland border down to Wilcannia in far-western NSW .
Lower Darling pastoralists have faced increasing bouts of dry times - even outside droughts.
The draft report – a version of which is understood to have been sent to the Turnbull government for comment – comes days after WaterNSW issued a red alert for blue-green algae on the Lower Darling River at Pooncarie and Burtundy.
Bourke is among towns also on stage-two water restrictions as the Darling dries up in places.
The paper by Murray-Darling Basin Authority's (MDBA) own scientists found flow behaviour had changed since 2000, particularly in mid-sections of the river such as between the towns of Walgett and Brewarrina.
On that section, low or no-flow periods were "difficult to reconcile with impacts purely caused by climate", the scientists said.
Indeed, dry periods on the river downstream from Bourke were "significantly longer than pre-2000", with the dry spells during the millennium drought continuing afterwards.
Water resource development – also described as "anthropogenic impact" – must also play "a critical role" in the low flows between Walgett and Brewarrina, the report said.
The Darling River is barely flowing south of Menindee Lakes. (The photo was taken on February 18 this year.)
Photo: Katharine McBride'Treachery'
The revelations come after the Senate last month voted to disallow changes to the $13 billion Murray-Darling Basin Plan that would have cut annual environmental water savings by 70 billion litres.
“The report is derived from data which belongs to the public, was prepared for public purpose by servants of the public using taxpayers' money, and should have been made available to the public," Rex Patrick, the Nick Xenophon Team senator, said, adding the information was "highly relevant to the Northern Basin Review debate".
"That it wasn't made available for Parliament's consideration is nothing short of a treachery," Senator Patrick said.
A spokeswoman for the authority said the report was "undergoing quality assurance processes prior to publication", with a formal release on its website likely in coming days.
The MDBA commissioned the internal team to "address some of the specific concerns raised" by its own compliance reviews and those of the Berejiklian government, she said.
Terry Korn, president of the Australian Floodplain Association, said the report confirmed what his group's members had known since the O'Farrell government changed the river's water-sharing plan in 2012 to allow irrigators to pump even during low-flow periods.
Poor policy had been compounded by "totally inadequate monitoring and compliance systems", Mr Korn said.
"Some irrigators have capitalised on this poor management by the NSW government to such an extent that their removal of critical low flows has denied downstream landholders and communities their basic riparian rights to fresh clean water," he said. "This is totally unacceptable."
Niall Blair, the NSW regional water minister, said the government was "aware of this report" but detailed comments would be premature until it was finalised.
"We have provided input to the MDBA to assist in the finalisation and publication of this work," he said.
"This kind of analysis assists the work of the NSW government in providing a robust and sophisticated compliance and enforcement approach in NSW rivers."
Fairfax Media also sought comment from federal Agriculture Minister David Littleproud.
Peter Hannam is Environment Editor at The Sydney Morning Herald. He covers broad environmental issues ranging from climate change to renewable energy for Fairfax Media.
Morning & Afternoon Newsletter
Delivered Mon–Fri.