By Jessica McSweeney
The substance believed to be behind the sudden appearance of neon green water in Sydney Harbour is a commonly used product for plumbers – but the culprits remain a mystery.
North Sydney Council engineers believe fluorescein, a chemical used in plumbing works, is most likely to blame for the green water that appeared in Kirribilli on Wednesday afternoon.
Neon green water was spotted in the harbour at Kirribilli on Wednesday. Credit: Nine News
Firefighters were called to the bay at Milson Park about 3pm after locals spotted the fluorescent green water flowing from a storm drain into the harbour.
Fire and Rescue NSW tests have so far shown no indications of toxicity.
“Because it is such an old, heavily populated area, it’s probably impossible to find where it started – there are probably thousands of points, like homes and stormwater drains, which lead into the harbour,” superintendent Adam Dewberry said.
“The mind boggles.”
Firefighters have ruled out nearby construction sites as the cause of the pollution. There’s no odour and no signs of corrosiveness.
One line of inquiry is if a prankster is to blame, potentially in a Year 12 muck-up day stunt.
A council spokesperson said the sight was “alarming” but council was reassured the bay was free of major pollutants.
“Spill socks were placed into the stormwater drain channel to stop further pollution from entering the bay. Sydney Water flushed the drainage system and by 6.40pm the drainage network was clear of the green water,” the spokesperson said.
“At this stage our engineers believe the substance is likely to be fluorescein, which is used as a dye for plumbing works. Fluorescein is a non-toxic substance and breaks down with UV light. The green colour is a feature that makes it easy to trace.”
A resident described the scene to Nine News as “green cordial, like radioactive stuff you see in superhero movies”.
Authorities hope Thursday’s deluge will disperse the last of the coloured water and return the bay to its usual hue. Sydney is experiencing widespread rainfall as a cold front moves up from the South Coast.
A hazardous surf warning is in place for Sydney.
“We expect to see widespread rain across much of eastern NSW … we are looking at a widespread 20 to 40 millimetres [of rain] in these areas today,” senior Bureau of Meteorology meteorologist Miriam Bradbury said.
North Sydney Council was contacted for comment.
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