Learn more about what we’re doing to ensure drinking water for our customers and communities is safe and is of the highest quality.
Our 2024-2025 testing has not detected PFAS in the source water supply (PFOS, PFHxS, PFOA and PFBS were all <2 ng/L). As concentrations of PFAS are below drinking water health-based guideline values, this water is considered safe to drink from a PFAS perspective.
Further information
- What are PFAS?
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PFAS (per- and polyfluoroalkyl substances) are a group of man-made chemicals widely used since the 1950s in various industrial and consumer products, such as
- Firefighting foams
- Non-stick cookware
- Cosmetics and sunscreens
- Fabric treatments, waterproof clothing and food packaging
Nicknamed ‘forever chemicals’ they can persist for a long time in the environment.
- Why we test for PFAS?
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- We comply with the Victorian Safe Drinking Water Act 2003 and follow the Australian Drinking Water Guidelines.
- Testing verifies that the water we harvest from our catchments and supply to your local water retail company is safe to drink.
- PFAS can travel long distances from their sources into waterways used for drinking water supply.
- Health-based guideline values aim to minimise health risks from PFAS over a lifetime .
- Monitoring water supply catchments can detect any rise in PFAS levels early.
- Monitoring for PFAS
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How we test
- We monitor the water harvested from our supply catchments using a risk-based approach for chemicals such as PFAS.
- We test for PFAS, including PFOA (Perfluorooctanoic acid), PFOS (perfluorooctane sulfonic acid), PFHxS (perfluorohexane sulfonic acid) and PFBS (perfluorobutane sulfonic acid), using accredited independent laboratory methods to compare against the current Australian Drinking Water Guideline values.
- All analyses are conducted at an independent, National Association of Testing Authorities- (NATA)-accredited laboratory with strict quality controls.
Where and when we sample
Our 2024-2025 monitoring program includes fortnightly sampling at seven protected and open catchment sites across Greater Melbourne. These include:
- two sites in the Yarra Ranges catchments
- two sites in the Tarago catchment
- one site near the Maroondah catchment
- one site in the mid-Yarra catchment
- one site near the Yan Yean catchment.
Test Limits of Reporting
Testing methods we use can reliably detect PFAS down to as low as 2 ng/L (nanograms per litre).
- Understanding the Numbers
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- A nanogram per litre (ng/L) is equivalent to one part per trillion.
- 1 ng/L is like one drop of water in 20 Olympic-sized swimming pools.
- New Guidelines Values
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The updated NHMRC guideline values (effective 25 June 2025) are now live:
- PFOS: less than 8 ng/L
- PFOA: less than 200 ng/L
- PFHxS: less than 30 ng/L
- PFBS: less than 1,000 ng/L
- These guideline values are very conservative and include wide safety margins, taking into account the latest scientific evidence to protect public health.
- Guideline values indicate the amount of PFAS in drinking water a person can regularly consume over a lifetime with negligible risk to health.
- We use these guideline values to inform our operational decisions and verify that the water we harvest is safe before we supply it to the retail water companies.
- How Our PFAS Monitoring Has Evolved
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- Melbourne Water began testing for PFAS in 2010 in water harvested from our open supply catchments.
- Early methods were still in development, without strict quality control, and tests that were not fully standardised or NATA-accredited, so the smallest PFAS concentrations we could detect at that time ranged from 5 to 30 ng/L.
- In 2018 the first Australian Drinking Water Guidelines for PFOS, PFHxS and PFOA came into effect, replacing earlier interim and draft values.
- Between 2010-11 and 2014-17, we conducted over 1,100 PFAS tests on catchment water; detections were rare, with more than 99% of results below early reporting limits (5-30 ng/L) and any detected levels below the relevant Australian draft guideline values.
- Since then, we have adopted fully-standardised, NATA-accredited methods with strict quality controls that reliably detect PFAS down to 2 ng/L, giving us greater confidence in low-level measurements.
- Next Steps & Transparency
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- If any future sample approaches a guideline value, we’ll investigate the source, consider further management options, and share our findings publicly.
- Melbourne Water is committed to rigorous science, open reporting and ensuring safe water is delivered to your taps.
- Learn More
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Your local water retailer also tests for PFAS in the drinking water supply network. By working together to monitor for PFAS at multiple points in the water supply network, we can verify that the water we supply meets safe limits and continue to provide high-quality drinking water for all our customers. For more information:
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Fact sheet by the Water Services Association of Australia.