PFAS and drinking water

What we know about PFAS

We know there's been community concern about the potential for drinking water contamination by PFAS from the Royal Australian Air Force (RAAF) Base Richmond. We've worked with our raw water supplier WaterNSW and consulted with NSW Health to assess any potential risk. NSW Health advised that there's no current evidence that PFAS is an issue. To be certain, Sydney Water has tested the drinking water at North Richmond Water Filtration Plant.

What is PFAS?

PFAS (per and poly fluoroalkyl substances) is a group of manufactured chemicals that include perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS).

Because these chemicals have fire-retardant, waterproofing and stain-resistant qualities, PFAS has been widely used in many industrial and consumer products worldwide. PFAS can be found in food packaging, non-stick cookware, fabric, furniture and carpet stain-protection applications, clothing, and some types of fire-fighting foams.

PFAS consists of very stable chemicals that bioaccumulate, do not easily break down and can persist in the environment for a long time.

What do the guidelines say about PFAS?

There are many types of PFAS. The Australian Drinking Water Guidelines specify limits for PFOS and PFHxS. These limits are:

• perfluorooctane sulphonate (PFOS) and perfluorohexane sulphonate (PFHxS) – a combined total of less than 0.07 micrograms per litre (µg/L)
• perfluorooctanoic acid (PFOA) – less than 0.56 µg/L.

Why test at North Richmond?

The Australian Department of Defence has investigated PFAS contamination at the RAAF Base at Richmond, which is considered a potential source of PFAS contamination in the local area. The North Richmond Water Filtration Plant sources raw water from the Hawkesbury-Nepean River.

The raw water inlet to North Richmond Water Filtration Plant is about 13 kilometres upstream of where water draining from the Richmond RAAF Base enters the river. There were community concerns about the potential for PFAS from the RAAF Base to contaminate the drinking water. To address these concerns, Sydney Water tested the water supply at the plant.

An initial monitoring program commenced in January 2019 and finished in April 2019. To address the specific concerns raised by the community, the program measured PFAS levels:

• in water sourced from the river over a range of tides, including high tide
• upstream and at the treatment plant intake
• in dry weather and after rainfall.

Sydney Water will continue annual testing as part of ongoing water quality monitoring.

What were the PFAS test results?

The results from the monitoring showed that the drinking water at North Richmond Water Filtration Plant meets the requirements of the Australian Drinking Water Guidelines. NSW Health advises that the drinking water supply at North Richmond is safe to drink.

The table below shows the test results for PFAS in the drinking water from North Richmond Water Filtration Plant are all well below the levels in the Australian Drinking Water Guidelines. Also included below are results from a University of Queensland study (Thompson and colleagues, Chemosphere, volume 83). This University of Queensland study in 2011 showed similar trace levels to our 2019 testing.
 

PFAS results in drinking water serviced by North Richmond Water Filtration Plant

• The first testing in January was done after 35–40 mm widespread rain in the area upstream of the North Richmond Water Filtration Plant and in the Richmond area.
• In the second testing triggered by rain, the rain only affected upstream of North Richmond Water Filtration Plant, in the Hawkesbury-Nepean River around Penrith.
• The third testing after rain was in response to a similar distribution of rain to the January rainfall. We tested after these 3 rain events to show if the levels in drinking water rose after local rainfall that might cause run-off from nearby land.
• As part of our ongoing monitoring of the North Richmond Water Filtration Plant, a fourth round of testing was completed in October 2023. It included testing following widespread rain (32 mm in 24 hours) upstream of the plant.

We completed the testing in consultation with NSW Health. Further information about the program is available if required.

Which other studies can we compare results to?

Previous studies have shown that trace levels of PFAS are detectable in drinking water around the world, so the levels found at North Richmond are unsurprising.

The 2011 University of Queensland survey of PFAS levels in drinking water in Australia showed that no levels exceeded the limits in the Australian Drinking Water Guidelines. The survey demonstrated that very low levels of PFAS are detectable in drinking water around Australia. The study also detected PFAS in bottled water.
 
The results from the North Richmond Water Filtration Plant were similar to those found in other areas tested as part of this University of Queensland study.

What about water in other areas?

PFAS is a low risk to Sydney's drinking water supply. Sydney's drinking water complies with the Australian Drinking Water Guidelines and is safe to drink. Since 2015, we've been working with WaterNSW and NSW Health to review the risks from PFAS in the water it supplies. While the understanding of these chemicals is still developing, the risk to drinking water in Sydney is considered low.

We're not currently monitoring other drinking water supplies.