Cascade Water Filtration Plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Blackheath |
0.0016 |
0.0012 |
< 0.0001 |
Katoomba |
0.0015 |
0.0013 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
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We regularly test the drinking water produced by our water filtration plants for perfluoroalkyl and polyfluoroalkyl substances (PFAS) and publish the latest results as part of our commitment to water quality. All drinking water samples tested for PFAS are within the current Australian Drinking Water Guidelines (ADWG).
We're in a transition period to lower PFAS levels in the Blue Mountains in readiness for the introduction of the updated ADWG, expected to be finalised and released by the National Health and Medical Research Council (NHMRC) later this year.
We're continuously reviewing and improving our practices around PFAS and drinking water.
We've been monitoring drinking water from the North Richmond Water Filtration Plant since 2019. In June and July 2024, we undertook sampling of treated water from the outlets of all our water filtration plants, and repeated sampling from the Cascade Water Filtration Plant because levels there were slightly higher than at other sites. We recently increased the frequency of monitoring the drinking water from the Cascade and North Richmond water filtration plants to weekly, and all other plants to monthly.
All results have been below the values specified by the Australian Drinking Water Guidelines.
We've conducted weekly testing of treated water at the Cascade Water Filtration Plant since 3 October 2024. Our water systems are dynamic. Residents in the Blue Mountains may receive water from either Cascade or Orchard Hills Water Filtration Plant. The interconnection between the Cascade and Orchard Hills systems varies depending on operational needs and storage capacity.
The PFAS results are trending down. We anticipate that this decline will continue and the results will be consistently below the proposed Australian Drinking Water Guidelines once the new mobile treatment plant and system have stabilised.
Drinking water sampling date | Cascade Water Filtration Plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|---|
29 April 2025 |
Blackheath |
0.0017 |
0.0012 |
< 0.0001 |
29 April 2025 |
Katoomba |
0.0015 |
0.0013 |
< 0.0001 |
22 April 2025 |
Blackheath |
0.0014 |
0.0014 |
< 0.0001 |
22 April 2025 |
Katoomba |
0.0013 |
0.0011 |
< 0.0001 |
15 April 2025 |
Blackheath |
0.0018 |
0.0014 |
< 0.0001 |
15 April 2025 |
Katoomba |
0.0017 |
0.0015 |
0.0001 |
8 April 2025 |
Blackheath |
0.0015 |
0.0014 |
0.0001 |
8 April 2025 |
Katoomba |
0.0014 |
0.0014 |
< 0.0001 |
1 April 2025 |
Blackheath |
0.0015 |
0.0014 |
< 0.0001 |
1 April 2025 |
Katoomba |
0.0015 |
0.0013 |
< 0.0001 |
25 March 2025 |
Blackheath |
0.0014 |
0.0014 |
0.0001 |
25 March 2025 |
Katoomba |
0.0014 |
0.0013 |
0.0001 |
18 March 2025 |
Blackheath |
0.0014 |
0.0012 |
< 0.0001 |
18 March 2025 |
Katoomba |
0.0017 |
0.0015 |
< 0.0001 |
11 March 2025 |
Blackheath |
0.0022 |
0.0018 |
< 0.0001 |
11 March 2025 |
Katoomba |
0.0022 |
0.0019 |
< 0.0001 |
3 March 2025* |
Blackheath |
Not available |
Not available |
Not available |
3 March 2025* |
Katoomba |
Not available |
Not available |
Not available |
24 February 2025 |
Blackheath |
0.0018 |
0.0014 |
< 0.0001 |
24 February 2025 |
Katoomba |
0.0014 |
0.0013 |
< 0.0001 |
17 February 2025 |
Blackheath |
0.0020 |
0.0015 |
0.0001 |
17 February 2025 |
Katoomba |
0.0022 |
0.0018 |
< 0.0001 |
10 February 2025 |
Blackheath |
0.0021 |
0.0014 |
0.0001 |
10 February 2025 |
Katoomba |
0.0021 |
0.0018 |
< 0.0001 |
3 February 2025 |
Blackheath |
0.0038 |
0.0025 |
< 0.0001 |
3 February 2025 |
Katoomba |
0.0027 |
0.0028 |
< 0.0001 |
28 January 2025 |
Blackheath |
0.0028 |
0.0024 |
< 0.0001 |
28 January 2025 |
Katoomba |
0.0030 |
0.0028 |
< 0.0001 |
20 January 2025 |
Blackheath |
0.0036 |
0.0026 |
< 0.0001 |
20 January 2025 |
Katoomba |
0.0043 |
0.0033 |
0.0002 |
13 January 2025 |
Blackheath |
0.0037 |
0.0030 |
< 0.0001 |
13 January 2025 |
Katoomba |
0.0034 |
0.0029 |
< 0.0001 |
6 January 2025 |
Blackheath |
0.0038 |
0.0033 |
< 0.0001 |
6 January 2025 |
Katoomba |
0.0035 |
0.0032 |
0.0002 |
31 December 2024 |
Blackheath |
0.0038 |
0.0037 |
< 0.0001 |
31 December 2024 |
Katoomba |
0.0038 |
0.0038 |
< 0.000 |
23 December 2024 |
Blackheath |
0.0052 |
0.0042 |
0.0003 |
23 December 2024 |
Katoomba |
0.0043 |
0.0037 |
0.0001 |
16 December 2024 |
Blackheath |
0.0056 |
0.0052 |
0.0004 |
16 December 2024 |
Katoomba |
0.0062 |
0.0056 |
0.0003 |
9 December 2024 |
Blackheath |
0.0067 |
0.0056 |
0.0003 |
9 December 2024 |
Katoomba |
0.0061 |
0.0051 |
0.0003 |
2 December 2024 |
Blackheath |
0.0069 |
0.0057 |
0.0003 |
2 December 2024 |
Katoomba |
0.0079 |
0.0068 |
0.0004 |
25 November 2024 |
Blackheath |
0.0081 |
0.0049 |
0.0002 |
25 November 2024 |
Katoomba |
0.0083 |
0.0058 |
0.0001 |
18 November 2024 |
Blackheath |
0.0069 |
0.0084 |
0.0002 |
18 November 2024 |
Katoomba |
0.0071 |
0.0080 |
0.0004 |
12 November 2024 |
Blackheath |
0.0098 |
0.0083 |
0.0006 |
12 November 2024 |
Katoomba |
0.0082 |
0.0097 |
0.0005 |
5 November 2024 |
Blackheath |
0.0079 |
0.0075 |
0.0004 |
5 November 2024 |
Katoomba |
0.0084 |
0.0068 |
0.0003 |
31 October 2024* |
Blackheath |
Not available |
Not available |
Not available |
31 October 2024* |
Katoomba |
Not available |
Not available |
Not available |
22 October 2024 |
Blackheath |
0.0100 |
0.0109 |
0.0006 |
22 October 2024 |
Katoomba |
0.0095 |
0.0104 |
0.0006 |
15 & 16 October 2024 |
Blackheath |
0.0084 |
0.0075 |
0.0005 |
15 & 16 October 2024 |
Katoomba |
0.0110 |
0.0081 |
0.0005 |
9 October 2024 |
Blackheath |
0.0118 |
0.0117 |
0.0006 |
9 October 2024 |
Katoomba |
0.0127 |
0.0147 |
0.0006 |
3 October 2024 |
Blackheath |
0.0089 |
0.0123 |
0.0004 |
3 October 2024 |
Katoomba |
0.0091 |
0.0123 |
0.0006 |
17 September 2024 |
Blackheath |
0.0108 |
0.0133 |
< 0.0010 |
17 September 2024 |
Katoomba |
0.0131 |
0.0139 |
< 0.0010 |
27 August 2024 |
Blackheath |
0.0134 |
0.0130 |
< 0.0001 |
27 August 2024 |
Katoomba |
0.0134 |
0.0143 |
< 0.0001 |
9 July 2024 |
Blackheath |
0.0147 |
0.0191 |
< 0.0001 |
9 July 2024 |
Blackheath (duplicate sample) |
0.0146 |
0.0160 |
< 0.0001 |
9 July 2024 |
Katoomba |
0.0140 |
0.0179 |
< 0.0001 |
25 June 2024 |
Blackheath |
0.0155 |
0.0136 |
< 0.0001 |
25 June 2024 |
Katoomba |
0.0164 |
0.0142 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
* Samples were collected, but results are not available as testing did not comply with our quality control criteria.
In April 2025, we conducted a more detailed and targeted PFAS monitoring program across locations in the Blue Mountains, as part of our commitment to water quality.
Jamieson and Shipley Reservoirs, which are intermittently used and provide very limited supply to customers, returned results that meet the current ADWG. However, they did return results that exceed the proposed new guidelines for PFOS.
Best practice is to repeat a sample if a test result is not typical, and repeat samples were collected from Jamieson and Shipley Reservoirs. The PFOS result for Shipley Reservoir was slightly lower than the first sample. The PFOS result for Jamieson Reservoir was higher than the first sample, but still within the current ADWG. It is not unusual to have some variability between sample results.
Despite the current ADWG requirements being met, we have isolated Jamieson Reservoir from the network while we empty, clean, disinfect and remove any sediment. It will be refilled with water from the Cascade Water Filtration Plant. The new water in Jamieson Reservoir will then be tested to ensure it meets both the current and proposed ADWG before it comes back online.
As part of this process, we will also test any sediment removed from Jamieson Reservoir. It will then be classified to the NSW Environmental Protection Authority's (EPA's) waste classification and disposed of accordingly.
Shipley Reservoir is also being depleted using tankers. It will be refilled with water from the Cascade Water Filtration Plant. The new water in Shipley Reservoir will then be tested to ensure it meets both the current and proposed ADWG.
These are the test results for the Blue Mountains water supply network (29.6 KB, XLSX) taken on 7 and 15 April 2025.
In 2018, the community raised concerns that PFAS from the Royal Australian Air Force (RAAF) Base Richmond could contaminate drinking water. In 2019, we undertook a targeted monitoring program to assess the potential for this to be the case. Our North Richmond Water Filtration Plant sources raw water from the Hawkesbury-Nepean River 13 kilometres upstream of where the water from the RAAF drains into the river. Therefore, the low readings are consistent with expectations.
Following the 2019 study, we conducted an annual monitoring program for the North Richmond plant. This commenced in November 2023. We've conducted weekly testing of treated water at the plant since October 2023.
Drinking water sampling date | Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|---|
28 April 2025 |
North Richmond |
0.0013 |
0.0024 |
0.0013 |
22 April 2025 |
North Richmond |
0.0012 |
0.0023 |
0.0012 |
15 April 2025 |
North Richmond |
0.0015 |
0.0029 |
0.0013 |
8 April 2025 |
North Richmond |
0.0012 |
0.0022 |
0.0012 |
31 March 2025 |
North Richmond |
0.0018 |
0.0035 |
0.0017 |
26 March 2025 |
North Richmond |
0.0015 |
0.0029 |
0.0015 |
17 March 2025 |
North Richmond |
0.0020 |
0.0031 |
0.0015 |
10 March 2025 |
North Richmond |
0.0018 |
0.0029 |
0.0015 |
3 March 2025 |
North Richmond |
0.0022 |
0.0034 |
0.0016 |
24 February 2025 |
North Richmond |
0.0012 |
0.0021 |
0.0012 |
17 February 2025 |
North Richmond |
0.0015 |
0.0021 |
0.0010 |
10 February 2025 |
North Richmond |
0.0015 |
0.0024 |
0.0013 |
3 February 2025 |
North Richmond |
0.0014 |
0.0016 |
0.0011 |
28 January 2025 |
North Richmond |
0.0014 |
0.0020 |
0.0011 |
20 January 2025 |
North Richmond |
0.0013 |
0.0022 |
0.0012 |
13 January 2025 |
North Richmond |
0.0014 |
0.0026 |
0.0010 |
6 January 2025 |
North Richmond |
0.0018 |
0.0030 |
0.0015 |
31 December 2024 |
North Richmond |
0.0021 |
0.0036 |
0.0012 |
23 December 2024 |
North Richmond |
0.0020 |
0.0027 |
0.0015 |
16 December 2024 |
North Richmond |
0.0024 |
0.0040 |
0.0015 |
9 December 2024 |
North Richmond |
0.0020 |
0.0032 |
0.0014 |
2 December 2024* |
North Richmond |
Not available |
Not available |
Not available |
25 November 2024 |
North Richmond |
0.0031 |
0.0040 |
0.0016 |
18 November 2024 |
North Richmond |
0.0014 |
0.0037 |
0.0012 |
12 November 2024 |
North Richmond |
0.0019 |
0.0034 |
0.0013 |
5 November 2024 |
North Richmond |
0.0019 |
0.0036 |
0.0016 |
31 October 2024* |
North Richmond |
Not available |
Not available |
Not available |
22 October 2024 |
North Richmond |
0.0015 |
0.0031 |
0.0014 |
15 & 16 October 2024 |
North Richmond |
0.0014 |
0.0034 |
0.0010 |
9 October 2024 |
North Richmond |
0.0013 |
0.0043 |
0.0014 |
3 October 2024 |
North Richmond |
0.0009 |
0.0031 |
0.0007 |
25 June 2024 |
North Richmond |
0.0011 |
0.0014 |
< 0.0001 |
15 January 2024 |
North Richmond |
0.0021 |
0.0019 |
< 0.0010 |
6 November 2023 |
North Richmond |
< 0.0020 |
0.0026 |
< 0.0010 |
14 September 2023 |
North Richmond |
< 0.0020 |
0.0019 |
< 0.0010 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
* Samples were collected, but results are not available as testing did not comply with our quality control criteria.
Drinking water sampling date | Weather | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|---|
29 April 2019 |
Dry |
0.0039 |
0.0036 |
0.0037 |
15 April 2019 |
Dry |
0.0041 |
0.0039 |
0.0037 |
4 April 2019 |
Dry |
0.0043 |
0.0031 |
0.0031 |
21 March 2019 |
Dry |
0.0028 |
0.0027 |
0.0017 |
19 March 2019 |
Wet |
0.0027 |
0.0028 |
0.0020 |
15 March 2019 |
Wet |
0.0030 |
0.0025 |
0.0019 |
5 March 2019 |
Dry |
0.0043 |
0.0037 |
0.0030 |
18 February 2019 |
Dry |
0.0036 |
0.0038 |
0.0029 |
23 January 2019 |
Wet |
0.0055 |
0.0042 |
0.0036 |
23 January 2019 |
Wet |
0.0057 |
0.0042 |
0.0038 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Commencing in October 2024, we increased our testing for PFAS at all our plants to monthly (except Cascade and North Richmond, which are tested weekly).
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
0.0007 |
0.0005 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
0.0003 |
< 0.0001 |
Illawarra |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Nepean |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Orchard Hills |
0.0012 |
0.0009 |
0.0005 |
Prospect |
< 0.0001 |
0.0008 |
0.0004 |
Warragamba |
0.0009 |
0.0008 |
0.0004 |
Woronora |
< 0.0001 |
< 0.0001 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
< 0.0001 |
0.0002 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
0.0002 |
< 0.0001 |
Illawarra |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Nepean |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Orchard Hills |
0.0010 |
0.0007 |
< 0.0001 |
Prospect |
< 0.0001 |
0.0007 |
< 0.0001 |
Warragamba |
0.0010 |
0.0008 |
< 0.0001 |
Woronora |
< 0.0001 |
< 0.0001 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
0.0003 |
< 0.0001 |
Illawarra |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Nepean |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Orchard Hills |
< 0.0001 |
0.0008 |
0.0004 |
Prospect |
< 0.0001 |
0.0008 |
0.0004 |
Warragamba |
0.0010 |
0.0008 |
0.0003 |
Woronora |
< 0.0001 |
0.0003 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
< 0.0001 |
0.0002 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
0.0002 |
< 0.0001 |
Illawarra |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Nepean |
< 0.0001 |
0.0002 |
< 0.0001 |
Orchard Hills |
0.0007 |
0.0006 |
0.0002 |
Prospect |
0.0007 |
0.0006 |
0.0003 |
Warragamba |
0.0008 |
0.0007 |
0.0004 |
Woronora |
0.0004 |
0.0002 |
0.0003 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
PFAS samples for Orchard Hills and Warragamba water filtration plants were resampled on 12 December as testing did not comply with our quality control criteria for samples collected on 2 December.
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Orchard HIlls |
0.0006 |
0.0007 |
0.0005 |
Warragamba |
0.0008 |
0.0006 |
0.0004 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
PFAS samples for Warragamba and Orchard Hills water filtration plants were collected on 2 December. Results are not available as testing did not comply with our quality control criteria. Resampling was conducted on 12 December.
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
< 0.0001 |
0.0003 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
0.0003 |
< 0.0001 |
Illawarra |
< 0.0001 |
< 0.0001 |
0.0003 |
Nepean |
< 0.0001 |
0.0002 |
< 0.0001 |
Prospect |
0.0007 |
0.0008 |
0.0005 |
Woronora |
< 0.0001 |
0.0003 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
PFAS samples for Macarthur, Illawarra and Woronora water filtration plants were resampled on 19 November as testing did not comply with our quality control criteria for samples collected on 4 November.
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
0.0004 |
0.0002 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
0.0002 |
< 0.0001 |
Illawarra |
< 0.0001 |
< 0.0001 |
0.0001 |
Woronora |
< 0.0001 |
< 0.0001 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
PFAS samples for Macarthur, Illawarra and Woronora water filtration plants were collected on 4 November. Results are not available, as testing did not comply with our quality control criteria. The next set of sample results will be published on 29 November.
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Nepean |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Orchard Hills |
< 0.0001 |
0.0008 |
0.0002 |
Prospect |
< 0.0001 |
0.0007 |
0.0002 |
Warragamba |
< 0.0001 |
0.0007 |
0.0002 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Macarthur – Appin |
< 0.0001 |
0.0002 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
< 0.0001 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Illawarra |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Nepean |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Orchard Hills |
< 0.0001 |
0.0008 |
< 0.0001 |
Prospect |
< 0.0001 |
0.0006 |
0.0004 |
Warragamba |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Woronora |
< 0.0001 |
< 0.0001 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
Water filtration plant | PFOS (µg/L) | PFHxS (µg/L) | PFOA (µg/L) |
---|---|---|---|
Illawarra |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Macarthur – Appin |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Macarthur – Campbelltown |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Nepean |
< 0.0001 |
< 0.0001 |
< 0.0001 |
Orchard Hills |
0.0012 |
0.0009 |
< 0.0001 |
Prospect |
< 0.0001 |
0.0008 |
< 0.0001 |
Warragamba |
< 0.0001 |
0.0001 |
< 0.0001 |
Woronora |
< 0.0001 |
< 0.0001 |
< 0.0001 |
ADWG values: PFOS + PFHxS = 0.070 µg/L, PFOA = 0.56 µg/L
We regularly test drinking water at all water filtration plants for a suite of other PFAS compounds, including 42 that don't have a specified PFAS value in the current Australian Drinking Water Guidelines. Download the spreadsheets below for monthly results.