Secret report shows likely source of ‘poo balls’ that closed Sydney’s beaches last summer

A secret report reveals the likely source of the fatberg balls that closed a raft of Sydney beaches last summer – with most coming from the deepwater ocean outfall at Malabar.

The partly redacted scientific report, obtained by Guardian Australia under freedom of information laws, points to a combination of heavy rains and a buildup of fats, oils and greases as the likely cause of the “poo balls” being discharged from outfalls at Malabar, Bondi and North Head.

But the NSW Environment Protection Authority (EPA) said on Friday that subsequent evidence “collected by Sydney Water … narrowed the origin of the debris to within the Malabar system”.

“Sydney Water’s Malabar wastewater treatment system has been identified as the likely source of debris balls that washed up on NSW beaches betwe