MEDIA RELEASE
Toxic pollution in Sydney’s drinking water catchment surges far beyond approved limits
11th December 2025
The Gardens of Stone Alliance is raising the alarm after extreme pollution levels were recorded yesterday morning in waterways feeding Sydney’s drinking water supply.
WaterNSW real-time monitoring shows that salinity levels in Wangcol Creek and the Coxs River are now up to ten times higher than the maximum levels set for treated mine water and far exceed national water quality guidelines.
Just a month after warnings about dangerous salinity spikes in the Coxs River, new data shows pollution levels have more than doubled, with no meaningful action taken.
Such readings indicate the presence of dissolved toxicants – including heavy metals – at concentrations that are acutely dangerous to aquatic life and pose a growing risk to downstream drinking water supplies.
These spikes follow years of community complaints and formal reports about illegal, unlicensed and excessive discharges from EnergyAustralia’s Mount Piper Power Station and Centennial Coal’s mines near Lithgow – yet the NSW Government has failed to halt the deterioration.
Jacqui Mills from the Nature Conservation Council of NSW, on behalf of the Gardens of Stone Alliance, said:
“This is the latest in a long line of warnings. The system is failing to protect Sydney’s drinking water catchment, and the government cannot keep looking the other way.”
“Every complaint, every dataset, every spike tells the same story: coal operations in Lithgow are polluting Sydney’s drinking water catchment, and government agencies are failing to stop it.”
Background
How the 10 December salinity readings compare to Australian and New Zealand Environment and Conservation Council (ANZECC) guidelines:
Both readings exceed the ANZECC guideline of 350 μS/cm for slightly disturbed ecosystems:
· Wangcol Creek recorded 3,298 μS/cm, over nine times higher
· On 10 November Wangcol Creek recorded 1,378 µS/cm (as noted in the 17 November NCC media release)
· Coxs River recorded 1,389 μS/cm, nearly four times higher
· On 10 November Coxs River recorded 963 uS/cm (as noted in the 17 November NCC media release)
What high salinity means
Salinity is not ‘just salt’ but reflects the total dissolved load of ions and contaminants, which could include:
· Sulphates and chlorides
· Heavy metals
· Other mine-derived toxins harmful to wildlife and water infrastructure
Extreme salinity causes
· Osmotic shock in fish and aquatic invertebrates
· Immediate toxicity at higher levels
· Long-term ecosystem collapse due to the elimination of sensitive species
History of community concerns and complaints
· Local volunteers have monitored creeks for 20 years, documenting repeated extreme pollution events.
· Multiple complaints have been submitted to the EPA and concerns raised with WaterNSW and the Department of Planning regarding unlicensed and non-compliant discharges.
· Today’s high salinity levels were confirmed by readings taken by Lithgow Environment Group and reported to the EPA for action.
Government agencies have repeatedly:
· Declined to impose salinity limits on key discharge points
· Allowed industry claims that contaminated releases count as acceptable ‘environmental flows’
· Failed to act on long-known water quality exceedances
· Allowed strict water quality rules for Sydney’s drinking water to be sidestepped
Image: Water from licensed discharge point LDP001, which flows into Wangcol Creek, photographed on 2 December 2025 when salinity measured 4,250 μS/cm.
Supplied by Lithgow Environment Group and used with permission.
ENDS
Media contact: Madeline Hayman-Reber
E: mhaymanreber@nature.org.au M: 0404 935 157
Note: Spokespeople are available for comment on request