A missing former boss, a looming class action and forever chemicals in our drinking water

On Sydney’s doorstep lies an ancient landscape of deep eucalypt forests, waterfalls and dramatic sandstone gorges.

The natural bushland of the Blue Mountains, according to UNESCO, is “of high wilderness quality and remains close to pristine”.

The water supply there has an enviable reputation, according to water scientist Ian Wright from Western Sydney University.

“This is the sort of water supply just about any community in Australia would dream of.”

But the discovery of man-made, long-lasting chemicals in the dam water here mid-last year has led to a breakdown of public confidence, and prompted a legal battle led by angry residents who no longer trust what comes out of their taps.

The PFAS found in Medlow Dam is now at the centre of a Water NSW investigation and a New South Wales parliamentary inquiry.

While the forever chemicals are a mystery, so is the sudden departure of Sydney Water’s managing director Roch Cheroux after six years in the job.

When asked by 7.30 Sydney Water gave little away.

The state-owned utility, responsible for supplying tap water, maintains the water in the Blue Mountains is safe to drink and there’s nothing to worry about.

Residents who have since discovered high levels of PFAS in their blood vehemently disagree. 

Shifting the goalposts

The Australian drinking water guidelines set the allowable limit of PFAS in water.

In July last year Water NSW, the body responsible for the state’s dams, found PFAS levels in untreated water in Medlow Dam exceeded those guidelines.

To be precise, 0.09 micrograms per litre, slightly above the acceptable level of 0.07 micrograms.

That prompted authorities to disconnect the dam and the adjoining Greaves Creek Dam as a precaution.

The water from Medlow Dam is filtered and treated before it reaches people’s homes so Sydney Water maintains it was safe to drink.

Sydney Water’s own tests in June last year found the tap water was within the guidelines.

But the guidelines are about to change with tougher standards expected to be revealed this year.

And under the proposed guidelines, the tap water from June last year would have exceeded acceptable limits.

The reason for this is a small change to the calculation for PFOS, which would have been four times higher than allowed under the proposed standards.

7.30 has been told the new guidelines are due to be released after the federal election.

Mystery surrounds managing director’s departure

Since the PFAS levels in Medlow Dam came to light Sydney Water’s mantra has been the tap water is safe to drink, but it has acknowledged it needed to improve its filtration system to comply with the proposed standards.

Now, almost a year since the Medlow Dam results, the tap water is well below the proposed limits after Sydney Water installed a temporary PFAS-filtration unit at its Cascade Filtration Plant at Katoomba.

Sydney Water has faced intense scrutiny at a NSW parliamentary inquiry, examining the extent of PFAS in water supplies across NSW.

In February Mr Cheroux fronted the committee, repeating Sydney Water’s reassurances.

But by March he was gone.

When asked why he left, Mr Plowman told 7.30 “the board made a decision to change the leadership”.

He would not say whether Mr Cheroux resigned or was sacked.

There’s also no explanation in the Minns government’s media release announcing his departure. 

When asked whether Mr Cheroux’s handling of the PFAS issue was a reason he left, Mr Plowman told 7.30, “I don’t believe so.”

“It is really important for everybody to understand that there’s 3,500 people that are absolutely committed to serving and providing essential services 24/7,” he said.

“It doesn’t matter whose hands are on the tiller [sic], the crew knows exactly what they’re doing.”

Residents prepare class action

Blue Mountains resident Jon Dee doesn’t trust the tap water, despite what Sydney Water insists.

He’s installed his own expensive filtration system under his sink.

Mr Dee, the co-founder of Planet Ark, is now leading the STOP PFAS group, which is preparing a class action against the government.

He wants the government to provide free blood testing for Blue Mountains residents, after tests he commissioned found high levels of PFAS in some of them.

One resident had three cancer cases in his family, however, it’s unclear if there’s a direct link between the water and their illness.

NSW Health told 7.30 “there is insufficient scientific evidence for a medical practitioner to be able to tell a person whether their PFAS blood level will make them sick now or later in life, or if any current health problems are related to the PFAS levels found in their blood”.

Water NSW has told 7.30 it has finalised its preliminary investigation into PFAS levels in the Blue Mountains and is consulting with the NSW Environment Protection Authority before it releases the report.

Those findings may shed light on a possible source of the chemicals, which the STOP PFAS group believes was a petrol tanker crash in 1992.

It’s yet another mystery, along with how long PFAS has been in the Blue Mountains water supply.

Both Water NSW and Sydney Water did not test for PFAS in the region prior to mid-2024.

“I think that’s regrettable. We should have done that in terms of due diligence.”

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