People who swam in Wollongong Harbour last week have been advised to consult their GP should they develop any symptoms associated with exposure to raw sewage.
The NSW Department of Health is still determining the health risk to the public from the sewage detected seeping into Belmore Basin from January 11.
A combined statement from Sydney Water, Wollongong City Council and the Environment Protection Authority yesterday said: "There is a chance that swimmers who used the water prior to Friday [January 17] are at increased risk of health problems.
"It is recommended that anyone who swam in the harbour and develops a stomach upset or skin irritation should see their GP."
The statement said that no reports of swimmers falling ill had been received.
The problem was first reported to Sydney Water on Saturday, January 11, but the harbour was only closed to swimmers on the afternoon of Friday, January 17.
The foul-smelling sewage has been leaking from a sandstone wall near the jetty at the harbour's southern edge.
After being alerted to the problem at 8.30pm on January 11, a Sydney Water crew was on site by 10 o'clock that night and found the leak was coming from a private main rather than one of Sydney Water's pipes.
A Sydney Water spokesperson said the inspectors were able to determine the leak came from a particular parcel of harbourfront land, but were unable to determine the exact source of the leak.
"While the source has not yet been confirmed, some faults in the sewer and wastewater system servicing the Fishermen's Co-op Building adjacent to the harbour have been identified and are being rectified," the combined agencies statement said.
Tests carried out by the property owner - NSW Trade and Investment Division of Crown Lands - confirmed the substance was sewage.
Details of the leak were provided to the EPA on the morning of January 13.
The spokesperson said Sydney Water inspectors returned to the site on January 16 and found the volume of seepage had "significantly reduced".
Sydney Water inspectors were back at the site yesterday, along with representatives from the EPA and Wollongong council, taking water samples from the harbour for further testing.
Dr Brian Morton, chairman of the Council of General Practice for the AMA, said there was a range of health implications from swimming in water contaminated with raw sewage.
"Normally, gut bugs ... and the high risk is swallowing the water, or getting the contaminated water into ears or other orifices," he said.
If a person swallowed a big enough dose of water they could get a stomach illness such as gastroenteritis, Dr Morton said.
Do you have health concerns after swimming in Wollongong Harbour during the past week?
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