Tank, Bore and Rainwater: Is Untested Water Safe to Drink?

Rainwater, bore and tank water are not covered by the Australian Drinking Water Guidelines and aren’t treated by a utility — so unlike mains water, their safety depends entirely on you. A well-maintained rainwater tank can supply good drinking water, but bore water and poorly maintained tanks can carry microbes or chemicals, so testing and treatment matter.

How is this different from mains water?

Mains tap water is disinfected, monitored and tested against the Australian Drinking Water Guidelines. Tank, bore and rainwater get none of that automatically — there’s no utility checking them, so the responsibility falls to the household.

Rainwater and tank water

According to the Better Health Channel, rainwater from a well-maintained tank is generally safe to drink if it’s clear, has little taste or smell, and comes from a clean catchment. The main risk is contamination from bird and animal droppings on the roof, which can introduce bacteria and parasites. To keep it safe:

• Keep gutters, roof and tank clean, and screen inlets to keep out leaves, animals and mosquitoes.
• Avoid collecting the first flush after long dry spells where you can.
• Vulnerable people (young children, elderly, pregnant or immune-compromised) may want extra treatment. The Australian Government’s enHealth publishes detailed guidance on rainwater tanks.

Bore and groundwater

Bore water carries more risk because it can be affected by farm runoff, septic leakage or naturally occurring chemicals and metals. Shallow bores in particular should be tested and usually disinfected before drinking. Never assume bore water is safe without testing it.

How to make tank or bore water safer

1. Test it — a lab test tells you what’s actually present (microbes, metals, nitrates).
2. Treat for microbes — boiling or disinfection handles bacteria and parasites.
3. Filter for taste, sediment and chemicals — an activated-carbon filter improves taste and reduces sediment and many chemical contaminants.

Remember: filtering improves taste and reduces many contaminants, but for untested tank or bore water it’s not a substitute for proper testing and disinfection.

Where a tap filter fits in

Filtering is optional rather than essential for safety on Australian mains water. If you do want to cut chlorine taste, sediment and microplastics, a point-of-use activated-carbon filter is one simple, low-cost option. PureFlow is one such tap-mounted filter, but the right choice depends on your water and your household — it is worth comparing the options and deciding what suits you.

Frequently asked questions

Is rainwater safe to drink in Australia?
From a well-maintained tank with a clean catchment, generally yes. Keep the system clean and consider extra treatment for vulnerable people.

Is bore water safe to drink?
Not without testing — bore water can carry microbes, metals or chemicals and usually needs disinfection.

Does boiling make tank water safe?
Boiling kills microbes but won’t remove chemicals or metals. See does boiling make water safer.