Lifeguards at Coogee Beach made the unusual find on Tuesday afternoon, prompting an immediate closure.
The debris, described as dark, spherical globs, ranges in size from golf balls to tennis balls. Randwick City Council is currently investigating the origin of the material, which they believe could be “tar balls”—a byproduct of oil spills or seepage, formed when oil mixes with debris and seawater.
Samples have been collected by local environmental officers for further testing, and the incident has been reported to the NSW Environment Protection Authority and Beachwatch NSW, a state-run beach water quality monitoring program.
More Sydney beaches closed
Following the closure of Coogee and Gordon’s Bay, Clovelly and part of Maroubra beach were shut to the public on Thursday.
Waverley Council has closed all of its beaches, including Bondi, Bronte, and Tamarama beaches on Thursday.
The beaches will remain closed while investigations are conducted by the NSW Environment Protection Authority (EPA) and other authorities.
“The wellbeing of our community is paramount, which is why we’ve taken the precaution to close our beaches,” said Mayor Will Nemesh.
Meanwhile, a major clean-up continued at Coogee Beach, where workers in Hazmat suits were seen removing potentially hazardous material along the shoreline. Randwick City Council has partnered with the EPA to handle the clean-up and dispose of the mysterious debris.
Preliminary tests indicate the debris is a “hydrocarbon-based pollutant” consistent with the composition of tar balls, which typically form when oil mixes with debris and water, often following oil spills or natural seepage.
Could be tar, or not
CSIRO principal research scientist Sharon Hook explained that tar balls typically come in various shapes, ranging from large, flat pancakes to small spheres. However, she noted that it was unusual for them to be perfectly round, as seen in Sydney.
“While these objects could be tar balls, it’s also possible they are something else,” Hook wrote in an article for *The Conversation* before the debris was identified by the council.
“I haven’t seen them firsthand, but from the images available, they appear to be relatively uniform and perfectly round, which is quite unusual for tar balls—though not impossible.”
The public has been urged to avoid touching the material.
