Sydney Water ordered to clean Malabar treatment plant where fatberg is birthing poo balls | Pollution

Sydney Water has been ordered by the New South Wales Environment Protection Authority to remove fats from its Malabar wastewater treatment plant following the discovery of a large fatberg linked to beach closures last summer.

Fatberg Responsible for Beach Closures

The size of the fatberg is currently unknown, but Sydney Water estimates it could be as large as four Sydney buses. Access to the area where it has accumulated is difficult.

A report obtained through freedom of information laws states that fixing the problem would require shutting down the ocean outfall – which extends 2.3km offshore – and diverting sewage to a “cliff face discharge,” potentially closing Sydney’s beaches for months. The report acknowledges this approach “has never been done” and is “no longer considered an acceptable approach.”

The EPA issued a pollution reduction program on Monday requiring “a range of significant works, including fat removal from the Malabar deep ocean outfall bulkhead area, to reduce the likelihood of further debris balls washing up on the state’s beaches.”

The requirements also include developing a system to capture debris during severe wet weather, a study into the formation of debris balls to improve tracking, and consideration of AI or other technology to monitor their formation.

Steve Beaman, NSW EPA executive director of operations, stated that Sydney Water is “responsible for ensuring it doesn’t pollute our beautiful beaches and this important work is a step towards that.” He added that the EPA will continue to regulate Sydney Water to protect the natural environment.

The August 2025 report suggests the fatberg formed due to “FOG [fats, oils and grease] accumulation in an inaccessible dead zone between the Malabar bulkhead door and the decline tunnel.” The bulkhead door is typically underwater and access is limited to low tide and low flows.

Sydney Water regularly cleans the accessible portion of the outfall, removing 53 tonnes of accumulated FOG and debris balls in April 2025. Debris balls first closed beaches in October 2024.

Initially, Sydney Water stated the debris balls “may have absorbed wastewater discharge” but did not form as a result of it. Subsequent reporting revealed this statement to be inaccurate. Sydney Water’s managing director, Darren Cleary, recently admitted the ocean outfall was likely the source.