PFAS (per- and poly-fluoroalkyl substances) are a family of man-made chemicals that have been used widely in industrial and consumer products since the 1950s.
PFOS (perfluorooctane sulfonic acid), PFOA (perfluorooctanoic acid) and PFHxS (perfluorohexane sulfonate) belong to this group of chemicals. PFAS are emerging contaminants that are persistent in the environment, and are commonly found in and around populated areas throughout Australia and internationally.
PFAS and drinking water
The quality of treated drinking water supplied by us is tested regularly throughout the water supply system. We ensure that it complies with the Australian Drinking Water Guidelines produced by the National Health and Medical Research Council.
In consultation with NSW Department of Health, we have adopted the ADWG values for PFAS of:
- less than 0.07 micrograms per litre for PFOS and PFHxS (combined); and
- less than 0.56 micrograms per litre for PFOA.
We routinely sample for PFAS in all of our drinking water supply zones, and report detections over 0.002 micrograms per litre, which is our independent laboratory's limit of reporting.
All results available to date show drinking water supplied by us is safe to drink.
Did you know?
We include PFAS results in our monthly Drinking Water Quality Report. View our monthly report.
PFAS and Grahamstown Dam/Tomago Sandbeds
Although Grahamstown Dam is only a few kilometres away from the RAAF Base Williamtown, the source of a local PFAS contamination plume, it is impossible for water to enter Grahamstown Dam from the RAAF Base due to the direction of surface and groundwater flows in the area. Water would need to flow uphill to enter the dam, even in wet conditions. This assessment is based on decades of ongoing hydrological testing and modelling.
Part of the Tomago Sandbeds has been affected by contamination from the RAAF Base Williamtown. We have embargoed, or isolated, two of our bore stations in the Tomago Sandbeds as a precaution while further investigations are undertaken. It is possible that some or all of these bore stations may be able to supply safe drinking water again in the future if appropriate management strategies can be implemented. The remainder of the Tomago Sandbeds is used as a backup water source, and the water is tested for contaminants, including PFAS, before it enters the drinking water supply.
PFAS in our environment
PFAS are emerging contaminants that are persistent in the environment, and are commonly found in and around populated areas throughout Australia and internationally.