Nambucca catchment snapshot contamination assessment

Between February and March 2026, the EPA and the NSW Department of Climate Change, Energy, the Environment and Water (DCCEEW) undertook a snapshot assessment of the health of the Nambucca catchment.

While there were some limited exceedances of metals above guideline values, only low levels of pollutants were detected across the river system. Based on the contaminants assessed, this means people can continue using the river for recreational activities.

The Nambucca catchment is within the Nambucca Valley Local Government Area on the mid-north coast of NSW, and includes the townships of Nambucca Heads, Macksville, Taylors Arm, Bowraville, Scotts Head and Valla Beach. The catchment is fed by local groundwater, the Nambucca River, Warrell Creek, Taylors Arm and other smaller tributaries.

The Nambucca area has a deep significance for the Aboriginal community and is under the cultural stewardship of the Gumbaynggirr people, the Nambucca Local Aboriginal Land Council (LALC), Unkya LALC and Bowraville LALC.

Land uses in the catchment include forestry, residential, agricultural, and a range of small to medium commercial and industrial facilities.

Testing approach

Surface water and sediment was collected from 19 sites in the Nambucca River and its tributaries (including Taylors Arm, Warrell Creek and smaller surrounding creeks).

Groundwater was collected from 2 sites and passive samplers were deployed at 7 sites. Passive samplers mimic how contaminants are absorbed and enter the food chain.

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Samples were tested for over 200 urban, agricultural and commercial/ industrial contaminants including:

• metals such as lead, arsenic, copper and zinc
• pesticides such as atrozine, permethrin, and triclosan
• pharmaceuticals and personal care products such as paracetamol and ampicillin
• per- and poly fluoroalkyl substances (PFAS) such as perfluorooctane sulfonic acid (PFOS) perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), and perfluorobutane sulfonic acid (PFBS).

Results

Overall, the assessment showed that contaminant concentrations in the Nambucca catchment were low.

Surface water

Copper and manganese were above the ecological guideline values at 2 sites, although the amounts of these metals that were in a form that could be taken up by plants and animals were below guideline values.

Manganese was above the recreational water quality guideline at 2 other sites.

The presence of copper and manganese are typically related to vehicle wear and tear.

Iron was observed above the ecological guideline value at 3 sites, although the amount of iron that was in a form that could be taken up by plants and animals was below the guideline value.

Iron can be naturally elevated in soils.

Sediment

The sediment quality guideline value was exceeded by arsenic at 2 inland river or stream sites, although the amount of arsenic that was in a form that could be taken up by plants and animals was below the guideline value.

Arsenic levels in soil are naturally high in the area due to the local geology.

Groundwater

Aluminium, cobalt, iron, manganese, nickel and zinc exceeded the aquatic ecosystem guideline values at 1 site.

Copper exceeded the aquatic ecosystem guideline value in groundwater at 1 other site.

Other key results

There were no PFAS detected in any surface water, groundwater or sediment samples above guideline values.

Pesticides and pharmaceuticals and personal care products were not detected in any samples above the limit of reporting for the lab.

Next steps

Results from this sampling program indicate that contaminant concentrations in the Nambucca catchment were low at the time of collection, and unlikely to pose a risk to the local ecosystem or human health.

This study provides important background information on contaminants in the catchment which can be used by EPA and local councils when responding to future pollution events and land use changes in the area.

We will continue to monitor the catchment in response to pollution events and other incidents such as fires to ensure the health of the community and the local environment.

The EPA recognises that this study is limited to a single snapshot in time, and the presence and level of contaminants in the catchment may vary throughout the year depending on rainfall and other factors.