Questions raised over decision to let cotton farms harvest first rainfall in years

New South Wales bureaucrats sought urgent advice from major cotton farmers about how recent rainfall might damage their water harvesting infrastructure, in an apparent effort to justify giving them the green light to retain the first rainfall in over a year, rather than letting it flow downstream.

On 7 February the government announced it would restrict the harvesting of overland flows throughout the northern Murray-Darling Basin for the first time, because it was “in the public interest”. But within days, the government had lifted the ban for two valleys and part of a third.

Emails obtained by the Guardian show the NSW Department of Planning, Industry and Environment asked irrigator groups for “urgent” advice on and examples of the sort of damage that their members might incur to levees, pumps and regulators if the water was allowed to flow across their land and then down the Barwon River to the Lower Darling.

But by the time the emails were sent, the NSW government had already given the large cotton growing areas a three-day exemption from the embargo.

That allowed several huge cotton properties between Walgett and Wee Waa, and west of Moree, to take the first flows in years.

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The Guardian understands the department received numerous representations from the cotton industry after the government declared the embargo.

The government rarely uses its public interest powers and so it detailed the reasons for the embargo.

These included “to cope with a water shortage”, to address a “threat to public health and safety” caused by critically low town water supplies and to “manage water for environmental purposes”, noting that the river system health was declining rapidly, putting aquatic biota at risk.

The cotton properties have extensive water harvesting infrastructure such as levees and pumps, which are used to divert overland flows into massive on-farm storages.

There is no information at this stage about how much water was harvested.

However, the proliferation of this infrastructure – only some of which is approved – has had a major impact on how much rainfall reaches the rivers in the northern Basin. Some estimates say historical flows have been reduced to 40% or lower.

The decision has angered farmers and communities in the lower Darling, where extremely dry conditions have led to mass fish deaths. Less water entering the river means it may not flow downstream and will instead seep into the dry riverbeds.

The email was sent at 3.46 pm on 10 February by Dan Connor, manager of the Healthy Floodplains Project, to the heads of the Gwydir Valley irrigators, the Namoi Valley irrigators and and Barwon Darling Irrigators.

“URGENT: requesting further details re: infrastructure risks from temporary FPH restrictions,” the subject line read.

“Could you please provide some examples of properties in your valleys where landholders have reported risks to infrastructure from not being able to take floodplain harvesting?

“Please supply; property name, contact details (if you have them handy) and a quick description of reported at risk infrastructure.”

The email was then forwarded by the irrigator bodies to the cotton growers.

This appears to have been after the exemption had been granted.

A spokesman for the department told the Guardian: “Following concerns during the rain event that the restrictions were exacerbating localised flash flooding, the department decided to take a precautionary approach due to the potential safety and infrastructure risks, and temporarily lifted the embargo in a limited area.”

But the independent NSW MP Justin Field said claims that the decision was taken to reduce the risk to infrastructure didn’t pass the pub test.

“This infrastructure is designed to divert flood water into on-farm storages,” he said.

“The minister has to explain what infrastructure was at risk, on whose request the decision was made, why such a large area was exempted from the embargo and how much water has been diverted,” he said.

A spokeswoman for the minister, Melinda Pavey, said she had not played a role.

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The department said: “We began investigations as soon as practicable, including an aerial review as soon as it could be arranged.”

The Natural Resources Access Regulator (NRAR) said its officers had flown from Tamworth to Walgett after the most recent rainfall/flood event.

“Of the properties observed it appeared that most had managed the volume of water, with limited infrastructure damage,” a spokeswoman said, noting this was not part of NRAR’s normal compliance activities.

“There was limited infrastructure damage to roads, channels, levee banks, and pumps,” she said.

The NSW Department of Primary Industry and previous ministers have come under scrutiny for providing preferential treatment to cotton interests in the past.

In the wake of a Four Corners program in 2017 which revealed a tape of senior NSW bureaucrats offering irrigators information so they could attack the Murray-Darling Basin plan, the head of the water division resigned.

An independent inquiry referred a number of matters to the NSW Independent Commission against Corruption. Despite two years of investigations there have been no findings to date.

The department said it was continuing to monitor river flows. The embargo is now in place for all designated floodplains until 28 February. More rain is expected this weekend.