Brown water from the tap: where it comes from and what to do first
Brown water looks alarming, and it is often harmless and short-lived. The trick is working out whether the problem is outside your property or inside it.
Brown water from the tap is usually iron or manganese sediment, stirred up in the mains or in your own pipes. Most of the time it clears within minutes. If it does not, or it keeps coming back, the cause is worth chasing.
Do not drink it or wash clothes in it while it is discoloured. Run a cold tap for a few minutes first and see what happens.
Check the cold tap before anything else
Open a cold tap that is not at the end of a long pipe run, such as the laundry tub or an outside tap. Let it run for two or three minutes. Fill a clear glass and hold it up to the light.
- Brown at first, then clearing. Sediment has been disturbed and is flushing out.
- Brown and staying brown. The source is probably the mains, or rusty pipework on your side of the meter.
- Cold clear, only the hot tap brown. The fault sits in your hot water system. See brown hot water for that case.
Why mains water turns brown
Mains pipes hold a fine layer of iron and manganese deposit. Anything that changes the flow can lift it. That includes a burst main, flushing of the network, firefighting or work on a nearby street.
If your neighbours see the same thing, it is almost certainly the network. Your water authority is the right call, not a plumber. Many authorities publish planned works and outage notices for your area.
Why it can start inside your property
Older galvanised steel pipes rust from the inside. Water that sits unused for weeks, such as in a holiday house, picks up that rust and comes out brown on the first use. A corroded fitting or an old tap can do the same job.
One tap that runs brown while the rest are clear points to that tap's own pipe. Every tap brown, cold and hot, points to the supply or the main pipework.
What to do while it is discoloured
Run the tap until it clears, starting with the one closest to where the water enters the property. Avoid the washing machine and the dishwasher until it is clear, because the sediment can stain clothes and clog filters. Check the water in the toilet cistern too, since that is a common place for rust to settle.
If the water does not clear after a long flush, stop using it for drinking and call your water authority. If only your property is affected, you need a licensed plumber to look at the pipework.
Is it the mains or your pipes? A quick comparison
| What you see | Points to | Next step |
|---|---|---|
| Neighbours have brown water too | The network | Call your water authority |
| Brown for a few minutes, then clear | Sediment stirred up and flushing out | Run a cold tap until it clears |
| Brown after a holiday or long absence | Rust in old galvanised pipes | Flush the line; ask a licensed plumber if it repeats |
| One tap only | That tap's pipe or fitting | Ask a licensed plumber to look |
| Only the hot tap | Your hot water system | Read brown hot water |
| All taps, cold and hot, stay brown | The supply or the main pipework | Stop drinking it and call your water authority |
Who to call about brown water
Call the right person first and you save time.
- Ask your neighbours. If they see it too, the cause is almost certainly the network.
- Check for planned works. Many authorities publish outage notices for your area.
- Call your water authority if it does not clear after a long flush, or if it is widespread.
- Call a licensed plumber if only your property is affected or one tap is always discoloured.
- Keep the sample. A clear glass held up to the light shows the colour when you describe it.
- Hold off on laundry. Sediment can stain clothes and clog filters.
Frequently asked questions
Is brown water from the tap safe to drink?
Do not drink it while it is brown. The discolouration is often harmless iron or manganese, but you cannot tell that by looking. Let it clear, and if it does not, contact your water authority.
Why is my tap water brown after the water was off?
Work on the mains, or a burst pipe, can stir up sediment in the network. Run a cold tap until it clears. If it stays brown, report it to your water authority.
Why is only my hot water brown?
That points at your hot water system rather than the mains. Check the cold tap first, then read our page on brown hot water.
When should I call a plumber?
Call a licensed plumber if the water stays brown after flushing, if only your property is affected, or if one tap is always discoloured.
Sources
What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.
- NHMRC. Australian Drinking Water Guidelines
- Sydney Water. Water supply, wastewater and stormwater services