By Ben Cubby
The NSW upper house will hold a wide-ranging inquiry into the risks of cancer-linked “forever chemicals” in the state’s drinking water.
The inquiry will examine testing and monitoring practices for per- and polyfluoroalkyl chemicals, also known as PFAS, as well as public disclosure of contamination levels and which communities are affected by tainted water.
A sediment sample containing PFAS chemicals from a waterway near Medlow Dam in the Blue Mountains.Credit: Wolter Peeters
It follows a series of reports in the Herald that established that there was no widespread testing for PFAS in drinking water, and revelations the chemicals were present in a creek flowing into a Blue Mountains dam at over 50 times the level considered safe for drinking water.
Medlow Dam and neighbouring Greaves Creek Dam in the Blue Mountains have now been disconnected from the drinking water supply network while an investigation into the pollution is under way, and the NSW government is helping all water utilities across the state screen for PFAS.
“The community has a right to be concerned about reports of PFAS in our drinking water supplies and that forever chemicals are spreading throughout the state’s waterways,” said the chair of the inquiry, Greens MP Cate Faehrmann.
“This committee will examine the adequacy and extent of monitoring of PFAS levels in our waterways and drinking sources, and the adequacy of reporting and disclosure to the public of any findings of contamination.
“Companies using PFAS have known for decades that these chemicals are toxic to humans yet have continued to suppress these facts while PFAS has continued to spread throughout the environment.”
Water NSW said this week it had tested samples from all “raw water” dams – drinking water storage sites that had not yet passed through a filtration plant – for PFAS in the Sydney, Illawarra and Blue Mountains regions.
While traces of the synthetic “forever chemicals” were detected at low levels in many dams, none were found to be close to breaching Australian drinking water guidelines, except for the elevated levels at the now-closed Medlow and Greaves Creek dams.
“New testing conducted by the state’s dam manager, WaterNSW, has confirmed that raw water in Greater Sydney’s dams – with the exception of the small, publicly inaccessible Medlow Dam – contains negligible PFAS levels,” the agency said in a statement.
“While the drinking water guidelines do not apply to raw, untreated water, these results are consistent with testing first published by Sydney Water in June that show Sydney’s drinking water remains within national guidelines.”
The investigation into PFAS contamination at Medlow Dam has seen over 100 water and soil samples analysed.
“Further testing has highlighted a small creek in the upper reaches of the Medlow catchment that flows into the dam, Adams Creek, as an area for targeted investigations,” Water NSW said.
The source of the contamination is unknown, though one line of inquiry is focused on the past use of firefighting foams at vehicle crash sites along the nearby Great Western Highway at Medlow Bath.
Fire retardant foams have not used PFAS chemicals since a ban in 2007.
US corporate giant 3M made billions from producing PFAS chemicals, which are useful for resisting heat, stains, grease and water. It has been accused of covering up the health risks associated with the products since the 1960s.
The World Health Organisation last year declared some of the PFAS family of chemicals to be carcinogenic.
The upper house inquiry, to be conducted by a committee of three government members, two opposition members and two crossbenchers, is set to report its findings on 20 June 2025.
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