“Excess” upstream irrigation, drought and water releases from the Menindee Lakes created the perfect storm that led to the ecologically disastrous fish kills over summer, according to scientists who prepared a report for Labor on the state of the Murray-Darling Basin.
Labor asked an independent panel of scientists to assess the river system in the wake of the scenes near Menindee in far-west NSW, where fish suffocated as blue-green algae died in the river and sucked up the oxygen.
Decades-old Murray cod were among the casualties.
Using data from NSW Fisheries, the report has found that millions of fish died in three separate events during summer.
“The conditions leading to this event are an interaction between a severe [but not unprecedented] drought and, more significantly, excess upstream diversion of water for irrigation,” the report said.
“Prior releases of water from the Menindee Lakes contributed to lack of local reserves.”
Panel chairman Professor Craig Moritz, director of the Centre for Biodiversity Analysis at the Australian National University, said the summer fish kills awakened people to the extent of the damage to the river system.
“To me, it was like the coral bleaching event for the mainland,” Professor Moritz said.
Our review of the fish kills found there isn’t enough water in the Darling system to avoid catastrophic outcomes.
“This is partly due to the ongoing drought. However, analysis of rainfall and river flow data over decades points to excess water extraction upstream.”
The panel has found “insufficient flows” pose a risk to the viability of the Darling River and the communities that depend on it.
The report also identifies “serious deficiencies in governance and management” which have “eroded” the intention of the 2012 Murray-Darling Basin Plan and the Water Act of 2007.
A six-month plan for urgent action, to reverse the decline, is laid out as part of the report.
Government and opposition studies ‘shared’ data
Opposition Leader Bill Shorten had initially written to the Prime Minister to ask for both political parties to back a combined study.
But after Labor engaged the Australian Academy of Science to do the work, the government announced its own separate scientific study into the fish kill.
That report, conducted by a group of scientists headed by Professor Rob Vertessy, is expected to be delivered to the Government on Wednesday.
However, the Academy of Science review confirms the two scientific panels have been sharing information.
Both panels were briefed by the Murray-Darling Basin Authority and the Commonwealth Environment Water Holder.
They also shared data and will review each other’s findings.
A state royal commission into the Murray-Darling was recently conducted in South Australia, containing damning and explosive findings about the “maladministration” of the river system.
A Productivity Commission report into the basin plan also pointed to conflicts and cost blowouts.
The Greens are calling for a federal royal commission to investigate the allegations. So far, Labor has stopped short of endorsing such a move.
But shadow water spokesman Tony Burke signalled last week that once these two scientific reports have been taken into consideration, that position may change.
“We will soon have four extensive pieces of analysis in to the Murray-Darling Basin – the Productivity Commission review, the South Australian Murray-Darling Basin Royal Commission, the Academy of Sciences review in to the fish kills and the review commissioned by the Minister,” Mr Burke said.
“Action needs to be taken now and the fish kills over summer have made clear just how urgent that action is.
“There may be a point where Labor supports a further royal commission in to this area, but right now we are about to have four significant sets of recommendations in front of us and the rivers need action to be taken urgently.”
Labor has announced it will attempt to overturn the cap on water buybacks as part of its response to the worsening state of the basin.