State water minister Rose Jackson has asked the office of the NSW chief scientist and engineer (OCSE) to conduct an independent review of the unprecedented deaths of millions of fish at Menindee.
Ms Jackson said the deaths sent shockwaves around the world and it was essential to better understand the cause and explore strategies to prevent a recurrence.
"We are requesting this independent inquiry to provide the community with certainty that we are thoroughly investigating this matter," Ms Jackson said.
"In this review, the NSW chief scientist and engineer will consider the likely cause of the fish deaths event, its effects, the overall response and then make recommendations on what needs to be done to stop this happening again.
"We anticipate the review will be completed and released by August 31. The findings and recommendations will drive the NSW Government's strategic response to what is undeniably an environmental event of massive proportions."
Millions of fish, including golden perch and cod were killed in the lower Darling-Baaka River near Menindee due to hypoxic blackwater, a naturally occurring phenomenon that causes extremely low dissolved oxygen levels.
The NSW government and local agencies continue to monitor the quality of Menindee's water supply to make sure it remains safe to drink.
Environment minister Penny Sharpe said OCSE had established a strong reputation for providing independent reports that deliver science-based recommendations that have gone on to shape government policy.
"For more than a decade OCSE has been providing an invaluable service to the NSW Government, particularly when impartial advice was needed about contentious issues," Ms Sharpe said.
NSW chief scientist and engineer Professor Hugh Durrant-Whyte said OCSE would be conducting a broad ranging inquiry, under the review's terms of reference.
"There is no doubt the extraordinary number of fish deaths has had a far-reaching effect on Western NSW and beyond," Professor Durrant-Whyte said.
"My office will be consulting broadly to examine the cause of the fish deaths and will seek advice from subject matter experts to shape the recommendations it will make to the NSW Government."
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