Australia’s failure to regulate flood plain harvesting was “a real embarrassment”, but the practice was unlikely to be illegal, the former chair of South Australia’s royal commission into the Murray-Darling basin plan has told a New South Wales parliamentary committee.
In scathing comments to the inquiry into the NSW government’s plan to licence flood plain harvesting, Bret Walker SC, one of the nation’s most highly regarded lawyers, said the failure of eastern states to address flood plain harvesting over the last 100 years was inconsistent with proper management of a valuable public natural resource.
Flood plain harvesting, done mainly in western NSW, involves farmers capturing flood waters that are flowing across their land into large on-farm storages.
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Modern farming methods, including laser levelling and building levees and channels to capture water, has led to a huge increase in the capture of flood waters, which has been blamed for up to 30% decline in inflows into the Murray-Darling river system.
Walker doubted the practice of capturing flood water flowing across a person’s property was an offence because it was not mentioned in the Water Act 1912, but he said NSW water laws were ridiculously convoluted and warned it might be possible for civil injunctions to be sought to stop the practice.
While most environmental groups agree that licensing flood plain harvesting is important, the lack of accurate data about the extent of water being taken has led to a major dispute over what amount should be licensed.
There is also dispute over how it should be accounted for in the “cap” which governs the amount of water each state can license farmers to extract from rivers under the Murray-Darling basin plan.
The NSW government has urged the upper house to pass the legislation quickly because it has had internal advice that the practice may now be illegal, putting some of the biggest agribusinesses at risk of prosecution. The crossbenchers and Labor blocked a makeshift solution earlier this year.
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Walker was asked to give independent advice to a NSW legislative council committee about whether exisiting flood plain harvesting was now illegal. He said he had actually been asked whether it led to offences and said he did not think so.
But he also stressed that it was not possible to give definitive advice without having facts to fully explore legality of flood plain harvesting.
He said it was not sensible to talk of ownership of H2O molecules, comparing it to the prospect of owning the air. But he also described as “absurd” that flood plain harvesting should be viewed as part of the commons and that people could take as much as they wanted.
The minister for water, Melinda Pavey, said that the advice from Walker was “a seminal moment” and she hoped that the parliament could now get on with the licensing of water.
She said the debate had been muddied by lobbyists with vested interests for too long.
Walker also criticised the Murray-Darling Basin Authority for its view that regulation of flood plain harvesting would not have any impact on the sustainable diversion limits (SDL) – the amount of water that can be extracted by agriculture under the plan.
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The authority says in its 2019 policy on flood plain harvesting: “Any changes to the baseline diversion limits that result from better measurement and certainty around the volume of water taken by flood plain harvesting will not have an impact on the environmentally sustainable limits of take. This is because the updated estimates do not give additional access to water.”
Walker described this view as “very mischievous” which dodged the central question regarding the protection and rehabilitation of the river system and “whether we have been taking too much [water].”
The authority has refused to appear before the NSW inquiry.
The inquiry has previously quizzed NSW water officials about emails which appeared to indicate their awareness of the inadequacy of their modelling on flood plain harvesting.
In a March 2018 email, the chief modeller, Andrew Brown, said that a new model did not have “to be fit for purpose to qualify as best available information”.
Maryanne Slattery, a former basin official who now works as a consultant, claimed the emails suggested the government and the authority were “trying to hoodwink everybody” into allowing caps on water take to be exceeded.Internet Explorer Channel Network