Fatberg the size of four buses likely birthed poo balls that closed Sydney beaches – and it can’t be cleared

Exclusive: Secret report suggests fats, oils and grease accumulate in ‘inaccessible dead zone’ at Malabar plant, then dislodge when pumping pressure ‘rapidly increases’

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A giant fatberg, potentially the size of four Sydney buses, within Sydney Water’s Malabar deepwater ocean sewer has been identified as the likely source of the debris balls that washed up on Sydney beaches a year ago.

Sydney Water isn’t sure exactly how big the fatberg is because it can’t easily access where it has accumulated.