Is Bore Water Safe to Drink?
Bore water can be safe to drink. Whether yours actually is depends on where you are, what geology your bore draws from, what's happened on the land above the aquifer, and how recently — if ever — your supply has been tested.
Unlike town water, bore water has no disinfection treatment and no regulatory monitoring. There is no authority checking your supply between tests. What comes out of your tap is untreated groundwater — its chemistry is determined entirely by the aquifer it draws from and the land use above it.
This article covers the main risk categories in Australian bore water supplies, how they vary by state and region, and what testing is required to know whether your bore water is safe to drink.
Why bore water isn't automatically safe
Municipal water supplies in Australia are treated with chlorine or chloramine, continuously monitored, and required to meet the Australian Drinking Water Guidelines (ADWG) at the point of supply. Your bore has none of these protections.
Water entering your bore has percolated through soil and rock over years or decades, dissolving minerals from the surrounding geology and picking up whatever has leached from the land surface above — agricultural chemicals, septic effluent, industrial solvents, and naturally occurring metals and radionuclides.
NSW Health, SA Health, and Queensland Health all explicitly recommend that bore water be tested and confirmed safe before use for drinking, cooking, or watering edible plants. The ADWG itself recommends testing where groundwater is used as a drinking supply.
The main risk categories
Microbiology — the primary concern everywhere
E. coli and Thermotolerant Coliforms are the primary indicators of faecal contamination in drinking water. In bore water, the most common sources are leaking septic systems, animal waste infiltration, compromised bore casings, and surface water intrusion into the aquifer.
Bore water has no chlorine residual to suppress bacterial growth. A casing that was sound when the bore was drilled may have deteriorated over years. Flooding events, nearby septic system failures, and bore disturbance during pump maintenance can all introduce bacterial contamination into previously clean bores.
The ADWG guideline for E. coli is zero detectable organisms per 100 mL. There is no safe threshold — presence at any concentration indicates the water has been in contact with faecal material and is not suitable for drinking without treatment.
Naturally occurring metals and radionuclides
Australian groundwater is chemically diverse, and natural geology is among the most significant sources of contamination in bore water. Key parameters vary significantly by region:
Arsenic — Naturally elevated in granite, sedimentary, and some volcanic geological units across Australia. Documented exceedances of the ADWG guideline of 0.01 mg/L occur in parts of NSW, SA, WA, and QLD. Arsenic has no taste, colour, or odour at concentrations of concern — chronic exposure above guideline values is associated with skin lesions, cardiovascular effects, and increased cancer risk.
Uranium — Leaches naturally from granite and sandstone formations across Australia, including large areas of NSW, SA, WA, and QLD. The ADWG guideline for uranium is 0.017 mg/L. Uranium is among the most commonly exceeded ADWG parameters in Australian groundwater — entirely from natural sources, with no visible sign in the water.
Manganese — Naturally elevated in many Australian aquifers, particularly in reducing conditions where dissolved oxygen is low. The ADWG health guideline for manganese is 0.5 mg/L. Long-term exposure above this level is associated with neurological effects. The aesthetic guideline is 0.1 mg/L — water above this level may stain laundry and fittings.
Iron — Extremely common in Australian bore water, particularly in the iron-rich geology of WA, SA, and coastal QLD. Not a direct health concern at typical bore water concentrations but causes staining and affects taste. Elevated iron often co-occurs with elevated manganese.
Lead — Can enter bore water from geological sources, from bore casing and pump materials, or from historical industrial land use above the aquifer. The ADWG guideline for lead is 0.01 mg/L — no safe threshold exists for lead exposure in children.
Fluoride — Unlike town water, where fluoride is dosed to a controlled level, bore water fluoride is entirely geological. Fluoride concentrations vary dramatically between aquifer systems — from near zero in some formations to well above the ADWG guideline of 1.5 mg/L in many inland NSW, SA, and QLD aquifer systems. Long-term consumption of water above this level is associated with dental and skeletal fluorosis.
Nitrate and nutrient contamination
Nitrate leaches from fertilised agricultural land and septic systems and accumulates in groundwater over time. Unlike surface water contamination which can flush with rainfall, nitrate in groundwater can persist for decades after the source has been removed.
The ADWG health guideline for nitrate is 50 mg/L as NO3. Elevated nitrate is of particular concern for households with infants under three months — at high concentrations it can cause methaemoglobinaemia by interfering with the blood's ability to carry oxygen. This is a serious and potentially fatal condition in very young infants.
Nitrate exceedances in Australian groundwater are most commonly associated with intensive agricultural land use — broadacre cropping, horticulture, and irrigated pasture — and with older septic systems in areas without reticulated sewerage.
PFAS — the emerging groundwater concern
PFAS compounds — per- and polyfluoroalkyl substances — migrate through soil into groundwater and persist indefinitely. They do not break down in the environment or in the body and have no taste, colour, or odour at concentrations above ADWG guideline values.
The primary contamination sources in Australia are defence bases, airports, fire training facilities, and industrial sites where aqueous film-forming foam (AFFF) was historically used. PFAS plumes in groundwater can travel significant distances from the source over years and decades.
The 2025 ADWG substantially tightened PFAS guideline values — PFOS is now limited at 0.00007 mg/L, a reduction of more than 90% from previous guidance. Standard laboratory reporting limits (0.01–0.05 µg/L) are no longer sufficient to assess compliance with these updated values. Trace-level detection at 0.001–0.005 µg/L is required for a meaningful result.
Properties near defence bases, airports, or industrial sites anywhere in Australia should include PFAS in their bore water test panel.
Agricultural chemicals — pesticides and herbicides
On rural and agricultural properties, bore water can contain residues of pesticides and herbicides that have leached through soil into the aquifer over years. Atrazine and simazine — widely used broadacre herbicides — are among the most consistently detected chemicals in Australian agricultural groundwater. Organochlorine compounds including dieldrin and DDT persist in groundwater long after their agricultural use has ceased.
Detection of agricultural chemicals in bore water is not limited to properties currently under cultivation — historical land use upstream or upgradient of a bore can contribute contamination long after the relevant activity has stopped.
Industrial solvents and volatile organic compounds
Chlorinated solvents including trichloroethylene (TCE) and tetrachloroethylene (PCE) are among the most common groundwater contaminants in Australia. They migrate from historical industrial sites, dry cleaners, and manufacturing facilities through the unsaturated zone into groundwater over decades. Vinyl chloride — a breakdown product of TCE and PCE — has a very low ADWG guideline value and is colourless and odourless at concentrations of concern.
VOC contamination is most relevant for bores near or downgradient of historical industrial land use — manufacturing precincts, dry cleaning facilities, fuel storage sites, and former industrial estates in urban and peri-urban areas.
How bore water risk varies by state and region
The specific risk profile of a bore water supply depends heavily on location. Some general patterns:
Western Australia — The Superficial Aquifer underlying Perth's Swan Coastal Plain is widely used for garden irrigation and, in outer metropolitan and rural areas, for drinking. Iron and manganese are elevated across much of the aquifer. PFAS contamination from RAAF Pearce, Perth Airport, and Jandakot Airport affects surrounding groundwater. Nitrate is elevated in parts of the northern and southern suburbs from historical horticultural activity.
South Australia — Some SA aquifer systems are naturally elevated in arsenic, fluoride, and uranium. The Padthaway and other agricultural regions have documented nitrate elevation from intensive horticulture. PFAS contamination from defence and industrial sites affects groundwater in some areas.
New South Wales — Granite geology across parts of central and western NSW can deliver elevated uranium and arsenic. Agricultural regions including the Liverpool Plains and Murray-Darling Basin have documented nitrate elevation. PFAS from defence bases including RAAF Williamtown and RAAF Richmond affects surrounding groundwater.
Queensland — Bore water is used extensively in rural QLD for both drinking and stock water. Naturally occurring arsenic is documented in some QLD aquifer systems. Agricultural chemicals from broadacre cropping in the Darling Downs and other farming regions can be present in groundwater.
Victoria and Tasmania — Bore water use is less widespread but occurs in rural areas. Similar natural geology risks apply.
The practical implication is that the appropriate test panel for bore water depends on where you are. A rural NSW property near cropping land near a defence base has a different risk profile to a Perth suburban garden bore — but both warrant testing before the water is used for drinking.
What testing is required
A bore water test appropriate for drinking water assessment should include at minimum:
Microbiology — E. coli and Thermotolerant Coliforms, with cold-chain sample transport
Metals and trace elements — a full panel of 22 metals including arsenic, lead, uranium, iron, manganese, and fluoride
Water chemistry — pH, EC, TDS, hardness, alkalinity, sodium, potassium, calcium, magnesium, chloride, sulphate
Nutrients — nitrate, nitrite, ammonia, and total oxidised nitrogen
For properties near PFAS sources, a 30-compound PFAS panel at trace detection level (0.001–0.005 µg/L) should be added. For rural and agricultural properties, a full pesticide, herbicide, and VOC screen is appropriate.
All testing should be conducted by a NATA-accredited laboratory under ISO/IEC 17025, with results compared against the ADWG. For microbiology, cold-chain sample transport is non-negotiable — samples must remain chilled from collection through to laboratory receipt.
How often should bore water be tested
Annual testing is the appropriate baseline for any bore used as a primary drinking supply. You should also test after:
Heavy rainfall following extended dry periods
Any maintenance on the bore, pump, or pressure system
Changes in taste, odour, or colour
Nearby land use changes — new development, changed agricultural activity, reported spill or contamination event
A PFAS advisory or notice for your area
Moving onto a property with an existing bore and no testing history
Groundwater chemistry is not static. A bore that tested clean two years ago may not reflect current conditions — particularly for nitrate, which varies with seasonal irrigation and rainfall recharge patterns.
If your results show an exceedance
A test result showing an exceedance of an ADWG guideline value tells you that a specific parameter is above the recommended level. Common responses:
E. coli or Thermotolerant Coliforms — inspect the bore casing and surrounding area, consider UV disinfection or chlorination, retest after treatment
Elevated arsenic, lead, or uranium — point-of-use reverse osmosis is the most reliable treatment; standard carbon filters do not remove these metals
Elevated nitrate — reverse osmosis or distillation; carbon filters do not remove nitrate
Elevated fluoride — reverse osmosis or activated alumina filtration
PFAS detected — reverse osmosis is the most broadly effective treatment
Treatment decisions should be guided by your specific results. The appropriate response to an arsenic exceedance is different from the appropriate response to a bacterial exceedance — your report results tell you what you are dealing with.
The short answer
Bore water can be safe to drink. The only way to know whether yours is safe right now is to test it. The most serious contaminants — E. coli, arsenic, uranium, nitrate, PFAS, and agricultural chemicals — are invisible, odourless, and tasteless at concentrations that may still exceed ADWG guideline values.
If your bore supply is your primary source of drinking water and it hasn't been tested in the last 12 months, testing is the appropriate next step.
For Perth-specific bore water information, see our Perth bore water drinking water safety guide.
Safe Water Lab provides mail-order bore water testing across Australia using NATA-accredited laboratory analysis. All results are benchmarked against the Australian Drinking Water Guidelines with plain-language explanations of any exceedances. View our bore water testing kits →