Thousands of dead fish have washed up on Sydney’s shores in “distressing” scenes.
The NSW Environment Protection Authority said it first found dead fish at Haslams Creek at Sydney Olympic Park last Thursday.
“Water quality monitoring indicates low dissolved oxygen in the water was the cause,” the department tweeted.
The low oxygen levels were believed to be a result of organic matter spilling into the waterways after heavy rain.
“Sydney Olympic Park Authority is cleaning up, but dead fish may be observed in the area over the weekend.”
Second fish kill in Parramatta River
The department later tweeted on Monday a second fish kill had been found at Parramatta River in Rydalmere which it also believed was caused by low dissolved oxygen levels in the water.
It called the find “distressing”.
Chris Bahjat, who fishes in the Parramatta River, spoke to the ABC describing the discovery as “disappointing”.
“I've seen a few fish kills but not like this," he said.
"Literally, thousands of thousands of dead fish, everywhere you walk, a metre apart."
The low dissolved oxygen levels causing the fish deaths has since been confirmed to Yahoo News Australia by a spokesperson for the department.
“Preliminary investigations indicate low oxygen levels were most likely due to natural causes,” the department said.
“Observations by EPA Officers indicate low oxygen levels were caused by high intensity storms that washed organic matter into the waterway, which combined with elevated water temperatures, has caused the fish deaths.
“It is difficult to provide exact numbers but EPA officers estimate a few thousand fish have died, potentially up to 4000, in the Parramatta River at Rydalmere.”
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