Know the major contaminants in Australian bore water sources and what the government agencies monitor to ensure that the water you consume is safe. Remediation services are essential for both government-owned and private water bore water sources to ensure that they are devoid of contaminants.
Key Takeaways
- Bore water contamination is unavoidable because these water sources lack natural cleansing processes
- The major contaminants of bore water include microbial contaminants, heavy metals, nitrates, VOCs, and PFAS
- Federal bodies, state EPAs, and government water utilities implement monitoring as per the state and federal laws and regulations
Underground bore water is not free of contaminants. But it is the major source of water for Australians, which led to the need for proper treatment of bore water to make it suitable for consumption. In Australia, more than 30% of groundwater is used for drinking water supply, mining, bottling, irrigation, and livestock. Among this, about 60 to 70% of groundwater use goes to agriculture, making it the largest consumer.
Therefore, it is the duty of the government to make sure that the water is free of contaminants so that it is healthy for consumption. But what are these contaminants? This blog will list those that exist in bore water and help you understand how they are monitored.
Why Bore Water Needs Independent Monitoring
Unlike mains water that is commonly used in urban areas, bore water is unregulated at the source. It is extracted from aquifers and then sent for treatment and filtration, making it unfit for direct consumption. Furthermore, groundwater from bores like the Great Artesian Basin (GAB), Perth Basin, or Murray-Darling Basin lacks natural cleansing processes like aeration and sunlight. This is why contamination persists and needs monitoring.
The 5 Contaminant Categories Agencies Monitor
The following are the major contaminants that are commonly found in bore water all across Australia.
1. Microbial Contaminants
The major microbial contaminants include E.coli, coliform, Legionella, Naegleria fowleri (Brain-eating amoeba), which are found in common bore water. Furthermore, poorly maintained (unchlorinated) bore water in Northern Australia might also contain Burkholderia pseudomallei, which causes melioidosis. In the case of rural bore water, they can even contain norovirus or protozoa. State health departments like NSW Health monitor these under the Public Health Act 2010.
2. Heavy Metals
Heavy metals that are common in bore water include arsenic, lead, manganese, and iron, which come from industrial activity and natural geology. Bore water in Australia also includes cadmium and aluminium in them as well. One study conducted in Western Australia shows that in 67 domestic bore water samples, they found sulphuric materials, including selenium. They also found acid sulphate soil in many locations. These are monitored by EPA agencies in all locations, like the SA EPA (South Australia), EPA NSW (New South Wales), and DWER WA (Western Australia).
3. Nitrates and Agricultural Chemicals
Nitrates, nitrites, and pesticide leaching, including insecticides, from fertilisers also seep through the ground and end up in bore water aquifers. There can also be animal waste or septic system leakage, and these are found in bore waters that are located in agricultural lands. According to the Australian Drinking Water Guidelines, 50 mg-NO₃/L (as nitrate) is set as a safe limit for bottle-fed infants. Alternatively, 100 mg-NO₃/L can be safely consumed by adults and children aged 3 months and older. These contaminants are monitored by the ANZECC/NWQMS trigger values.
4. Volatile Organic Compounds (VOCs) and Hydrocarbons
These contaminants come from underground fuel tanks, industrial solvents, and landfill leachate. These contaminants include chlorinated solvents and benzene that require NATA-accredited testing to ensure that the water is safe to consume. Common VOCs include petroleum hydrocarbons, toluene, xylenes, trichloroethylene, and perchloroethylene. These are monitored by the ASC NEPM (Assessment of Site Contamination Measure) with “Health Screening Levels (HSLs)” for petroleum hydrocarbons and “Groundwater Investigation Levels (GILs)” to manage contamination.
5. PFAS (Per – and Polyfluoroalkyl Substances)
Lastly, the “forever chemicals” are emerging contaminants in Australian bore waters, originating from firefighting foam and industrial waste. NHMRC says that PFAS exposure occurs through multiple pathways, 10% of the total exposure being from drinking tap water. The following are the safe Australian Drinking Water Guideline levels of PFAS*, and consuming more than that can cause health risks.
- PFOS: 8 ng/L (Less than 0.008 micrograms per litre)
- PSHxS: 30 ng/L (Less than 0.03 micrograms per litre)
- PFOA: 200 ng/L (Less than 0.2 micrograms per litre)
- PFBS: 1000 ng/L (Less than 1.0 micrograms per litre)
*as of June 2025
These are monitored by NHMRC, DCCEEW, and the state EPAs. If your bore water exceeds these levels, the water needs advanced treatment before it is deemed suitable for consumption.
Also Read: How Bore Water Testing Supports Sustainable Groundwater Use in Australia
Which Government Agencies Are Responsible for Monitoring?
Understand where your bore water monitoring falls in the jurisdiction and who is responsible for managing it. However, the following do not apply to private bore owners and will be explained separately.
- Federal Bodies: The federal bodies include NHMRC (Australian Drinking Water Guidelines), DCCEEW (that oversees water quality & PFAS NEMP), Australian CDC (supervises public health), and the Bureau of Meteorology (that studies and takes action based on groundwater data).
- State/Territory EPAs: State EPAs include EPA NSW, EPA SA, DWER WA, and EPA Victoria. All these bodies enforce regulation management and contamination reporting laws, as well as the legal requirement to notify upon contaminant discovery.
- Water Utilities: Government bodies include WaterNSW and Water Corporation WA, which are responsible only for the reticulated supply of water from government-owned bores, not private ones.
- Private Bore Owners: Monitoring these contaminants and bore water quality falls outside the government utility oversight. If you are a bore/land owner, you need to monitor them yourself and can only consult with accredited environmental and site remediation services like SERS. We can help you assess, test, and clean bore water sources with our NATA-accredited laboratory procedures.
Summing Up, Here’s What You Should Know Overall
| Contaminant Category | Key Examples | Main Monitoring Body |
|---|---|---|
| Microbial | E. coli, Naegleria fowleri, Legionella |
State Health Departments |
|
Heavy Metals |
Arsenic, lead, iron, and manganese | State EPAs (EPA NSW, DWER WA, EPA SA) |
| PFAS | PFOS, PFOA, GenX chemicals |
NHMRC, DCCEEW, State EPAs |
|
Nitrates & Agricultural Chemicals |
Fertiliser runoff, pesticides, herbicides | ANZECC / NWQMS framework |
| VOCs & Hydrocarbons | Fuel leaks, solvents, landfill leachate |
ASC NEPM / State EPAs |
Table 1: Contaminants and Monitoring Body
How the Monitoring is Conducted
Although it is not required for everyone to know what bore water monitoring involves, this can be useful for people who manage their own bores.
- Field sampling is the first step, where bore water is collected for testing through composite sampling, grab sampling, or automated sampling. Some remediation services also use in-situ probes and real-time telemetry or sampling.
- Laboratory analysis is done through extensive testing in NATA-accredited laboratories.
- Hydrometric services come next for monitoring the hydrological cycle, which affects the aquifer levels, water quality, and water flow. Testing is done either annually or biannually for private bores, usually after noting changes in taste, colour, or odour.
- Data analysis and reporting are the final steps conducted by the remediation services to assess the quality of water and the contaminants present.
Bore Water Needs Proper Assessment and Quality Checks! Hire Remediation Services
Bore water is not inherently unsafe, but it is when it is unmonitored. You will only know the difference between unsafe and unmonitored when the harm is done. So, do not just keep extracting water from the bores. Ensure that the water levels are kept in check alongside the quality and contaminants. Hire SERS to get trusted assessment and monitoring services!
Frequently Asked Questions
1. Does the Depth of My Bore Affect the Level of Water Contamination?
Not really. Usually, shallower bore water is more contaminated because of surface runoff and agricultural chemicals. On the other hand, deeper aquifers, even though they stay protected by thick soil layers from runoffs, have higher levels of naturally occurring minerals or arsenic.
2. Can I Use Home Filtration Systems to Make Contaminated Bore Water Safe for Drinking?
No. Standard jug filters cannot filter the complex heavy metals or PFAS found in Australian groundwater. You can, however, treat the water through specialised systems like reverse osmosis or activated carbon, which should only be installed after professional NATA-accredited testing.
3. Do Seasonal Changes or Heavy Rainfall Impact the Quality of My Bore Water?
Yes. Heavy rain can replenish groundwater but will wash surface pollutants, bacteria, and fertilisers, adding them to the bore water. And during droughts, the concentration of dissolved solids and minerals gets higher as water levels drop, making regular testing essential.
4. Are There Specific Legal Obligations for Businesses Using Bore Water for Commercial Purposes?
Yes, businesses must comply with the General Environmental Duty (GED, applicable to Victoria and Queensland) and similar regulations to prevent harm. Failure to monitor and manage contaminants can lead to significant penalties from the EPA.
