Massive fatberg forces Sydney Water into risky clean-up that could divert sewage, close beaches
Sydney Water has been ordered by NSW’s environmental watchdog to clean up oil blocking the Malabar deepwater ocean drain.
The Environmental Protection Authority (EPA) has called for a pollution reduction program to be carried out at the waste management facility, potentially involving “fatbergs” the size of four Sydney buses.
The decision comes a month after Sydney Water was revealed to be the culprit in mysterious sewage balls washing up on NSW beaches in 2024 and 2025.
NSW EPA operations manager Steve Beaman said Sydney Water “has a responsibility to ensure it does not pollute our beautiful beaches and this important work is a step towards that”.
The Sydney Water assessment report in August last year found that poop balls were caused by solids, liquids and grease accumulating in Malabar’s sewer tunnels and chambers.
Repairing the accumulated oil mountain proved to be a challenge, as the only accessible area (the compartment entrance) was underwater and could only be accessed during low tide.
However, no matter how risky the cleaning work is, it is stated that the accessible areas of the Malabar sewage plant are cleaned regularly.
It was reported that 53 tons of accumulated waste in April last year was cleared.
When the sewage plant maintenance system was first designed in the 1980s, waste was diverted to flow over Sydney’s cliff faces and beaches.
However, the report found that such maintenance “was not undertaken at all” and was “no longer considered an acceptable approach”.
The report said the chamber would only be accessible by decommissioning the plant, which would ultimately lead to waste being diverted onto Sydney’s cliff faces, which would block Sydney’s beaches.
He added: “The waste room is not designed to be maintained regularly.”
On Monday, the NSW EPA said Sydney Water’s pollution reduction program would require “a number of significant works, including the removal of oils from the Malabar deep ocean current baffle area, to reduce the likelihood of further balls of debris hitting the state’s beaches”.
A Sydney Water spokesperson said in a statement that the utility would “implement these measures in close collaboration with the EPA” and work closely with the independent Wastewater Expert Panel, local councils, government agencies and the community.
The NSW EPA also ordered Sydney Water to develop “a system to capture debris overflowing from sewers during severe wet weather events” after investigations into the cause revealed a loss of power to the plant in October 2024 stopped raw sewage pumps for four minutes.
This loss of power created a “rapid rise to high flow again” after power was restored, dislodging some of the oil mountain that had accumulated behind the compartment door.
A similar result was created in January last year when the pressure first decreased and then increased “due to rainy weather”.
“The debris pellet is a complex problem and the EPA will continue to regulate Sydney Water to protect our precious natural environment,” Mr Beaman said.
