The letter requested WaterNSW investigate the use of two of the Harris' water licences and came almost three months before ABC's Four Corners aired allegations of water theft in the Barwon-Darling, including by the Harris family.
Last week, WaterNSW finally brought a prosecution against the Harris family, alleging water extraction when flow conditions did not permit it, and that they had breached licence and approval conditions. It also prosecuted three members of the Barlow family for similar offences.
Mr Harris said in a statement last week that he had yet to be served evidence: "We look forward to an opportunity to vigorously defend these allegations in a legitimately constituted forum where the rule of law
Mr Harris also said last week's summons "was the first time WaterNSW has raised this matter with us", a stance he re-affirmed when contacted by Fairfax Media through his media advisor.
The Harris comment stands in contrast with WaterNSW's reply on June 19 to EDO's April letter, in which Susi Curtis, the agency's general counsel, said her agency was "actively investigating certain of the matters" and that it anticipated the investigation would "be finalised by November 30, 2017".
A spokesman for WaterNSW declined to comment as "this matter is before the courts". A spokeswoman for Niall Blair, the regional Water Minster, directed inquiries to WaterNSW.
However, the subsequent lack of action by WaterNSW – even after the widespread publicity and public inquiries prompted by the Four Corner program – prompted EDO NSW to initiate civil enforcement action on behalf of the Inland Rivers Network, an environment group.
Mr Harris is also fighting that action.
"We took on this case to protect the health of the Murray-Darling Basin river system, which relies on proper compliance with the law," Elaine Johnson, EDO's principal solicitor, said.
"Since the Four Corners investigation was aired in July, numerous investigations and reports have raised serious questions about failures by the regulator to prosecute water theft in NSW."
The urgency for action was underscored by poor rainfall during the middle of 2017 and an outlook of below-average rain for July-September.
"Ongoing breaches … relating to the illegal over-extraction of water from the Barwon-Darling River System may have significant impacts on the environment, and downstream communities and water users," EDO solicitor Brendan Dobbie wrote in a follow-up letter to Ms Curtis, dated August 18.
WaterNSW's poor enforcement record will likely be highlighted further when the Ombudsman releases his final report, expected to be tabled in June.
"It will examine individual compliance cases as well as make broad observations about the conduct of compliance and enforcement functions," Chris Wheeler, deputy Ombudsman, told Fairfax Media.
The Ombudsman last week tabled a corrective report, highlighting that compliance figures given to it by WaterNSW had been wrong. Instead of 117 penalty infringement notices or prosecutions in the 16 months from July 2016, there were in fact none.
"I'm not aware of any previous [Ombudsman's] report that had to correct the record," Mr Wheeler said.
Much of the Darling River downstream of Bourke currently has blue-green algae alerts and limited or no water flows.
On Thursday, Mr Blair issued an embargo on water extraction action on the Barwon-Darling river system to ensure expected floodwaters from heavy rains in Queensland made it at least as far as the Bourke weir pool.
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.
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