This article is more than 1 year old

This article is more than 1 year old

The New South Wales Natural Resources Commission has warned the water minister she is “shooting the messenger” over their findings that water management in the Barwon-Darling river had brought on drought conditions in the Lower Darling three years early.

The Sydney Morning Herald has obtained correspondence from the commission in which it strongly refutes the minister’s assertions that its report on management of NSW’s largest river was wrong or tarnished by a conflict of interest by its scientific expert, Professor Fran Sheldon.

“Never in my time as commissioner have I been publicly criticised by a minister for the quality or process of our work,” the chair of the commission, John Keniry wrote in the letter sent to Melinda Pavey, planning minister Rob Stokes and environment minister Matt Kean.

Coalition divided over water policy in wake of damning Barwon-Darling report Read more

“I fear you minister are ‘shooting the messenger’ for the failures of the 2012 water-sharing plan,” Keniry wrote.

The NRC has recommended that the new rules for the Barwon-Darling should raise the cease-to-pump threshold, which would limited the ability of irrigators to pump when the river is low.

The NSW Nationals and senior Liberals responsible for the environment are increasingly in conflict over issues that that the Nationals see as crucial for rural communities.

Pavey told the Sydney Morning Herald: “This is not personal, it is a matter that carries the weight of government decisions which impacts communities and could cost the taxpayer millions of dollars,” she said.

The proposed new rules would have significant impacts for cotton growers around Brewarrina and Bourke, and would likely trigger calls for compensation. The federal government has proposed buying out A-class licences to reduce the extraction demands.

In the case of the Barwon-Darling water-sharing plan, the lion’s share of water entitlements are held by a handful of major agribusinesses that grow cotton. But the same rules have deeply angered graziers in the Lower Darling where the river has ceased to flow.

In earlier correspondence, Pavey had slammed the conduct of the NRC, suggesting it had left itself open to conflicts of interest because Sheldon had been peer-reviewed by scientists she had worked with over the years. She also said Sheldon had not used the latest driver management data.

In her letter to Keniry on Sunday, Pavey wrote she was “seeking a re-evaluation of the data and processes that were undertaken to inform the draft report of the Barwon-Darling ... plan”. She also asked WaterNSW to produce a rapid alternative analysis.

Facebook Twitter Pinterest NSW water minister Melinda Pavey. Photograph: Dean Lewins/AAP

The Barwon-Darling water-sharing plan includes controversial rules on when irrigators can pump during low flows and rules that allow irrigators to take up to 300% of their entitlement in one year if they have sufficient credit in their water accounts.

This has led to irrigators being able to take large amounts of water out of river into private storages in the leadup to the drought.

Guardian Australia has reported that the previous National party water minister Katrina Hodgkinson made these late changes to the plan after it had been signed off by her department and after public exhibition.

The NRC found that the high level of extractions had led to the Lower Darling going into hydrological drought three years early.

Other independent reviews have also expressed concerns about the Barwon-Darling water-sharing plan.

The Murray-Darling Basin water compliance review by the Murray-Darling Basin Authority found the Barwon-Darling water-sharing plan failed to “provide adequate protection for environmental water, particularly during low flows”, potentially inhibiting achievement of the environmental and social outcomes of the basin plan.

The rules were also criticised in the South Australian Murray-Darling Basin royal commission report, which found “the amendments made in October 2012 to the NSW Barwon-Darling water-sharing plan have almost certainly contributed to decreased flows south of Bourke, and an increase in no-flow events, and their duration”.

The Vertessy report was commissioned by the federal government after last summer’s fish kills found that “changes to Barwon–Darling water access arrangements made by NSW just prior to the commencement of the basin plan in 2012 have enhanced the ability of irrigators to access water during low flow periods and during the first flow event immediately after a cease-to-flow period”.

“Whilst we would not assert that excessive water extractions caused the lower Darling fish deaths in 2018-19 per se, it is clear that historic patterns of extractions in the northern basin over the last two decades (and particularly since 2012) have reduced the resilience of riverine ecosystems in the lower Darling … As such, water access and water sharing arrangements in the Barwon–Darling should be reviewed and modified.”