Sydney homes filled fumes after leak at Camden Valley Way petrol station

For more than a week, residents in Sydney's south-west have been living with the smell of petrol fumes filling their homes.

Concerned for their health, residents of Prestons, near Liverpool, begged local authorities to do something about it.

Using the kitchen and the bathroom caused literal headaches for Michael Andjelkovic.

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"It's coming up through the toilet and the drains - the odours come through here," he told 9News.

The stench of petrol has been coming from the sewer system, leaving him and his neighbours on Dalmeny Drive feeling sick.

"The smell is very overpowering, mostly at night - hits you in the face," local resident Julie said.

With her children suffering respiratory issues, they've had to resort to sealing around their doors with duct tape.

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"As far as I know six streets have been impacted," local resident Julie said.

There are concerns too for the local environment.

"Not far from here is the local water system and playing fields," Member for Leppington Nathan Hagarty said.

"Once we sort out this in the short term, we do have some families with even with a thin line of film across their pool, we need to look at remediation and compensation as well."

Sydney Water identified a petrol station on Camden Valley Way as the source of the problem.

Today the station was closed.

"Sydney Water has blocked off the connection between our service station and the sewer main," Ampol said in a statement.

"We are currently undertaking integrity testing of fuel lines and underground tanks, with results to be available next week."

Work is now beginning to flush the sewer.

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