Effects of bushfires on water quality

How bushfires affect water quality

Bushfires can affect water quality to varying degrees. This depends on factors such as:

• the size and intensity of the fire
• the time between the last fire and a significant rainfall event
• the type of surrounding vegetation and soil

The National Health and Medical Research Council (NHMRC) sets the guidelines for drinking water quality. State and territory governments use these guidelines to regulate the supply of drinking water to Australian communities.

It can be difficult to treat bushfire-affected water so that it’s suitable for human consumption. In some cases, you may need to rely on enhanced treatment or use alternative water sources.

Town water supplies

Drinking water providers regularly monitor town water supplies. Drinking water providers will let you know if your bushfires have affected local drinking water, and what to do about it.

Rainwater tanks

Ash, debris and fire retardants can affect the appearance and taste of rainwater but are unlikely to be a health risk.

Bushfires can also contaminate rainwater tanks. An alternative water source is recommended.

Use an alternative safe water supply for drinking, preparing food or ice and cleaning teeth if:

• your rainwater or other private water source looks or smells unusual
• you suspect it has been contaminated

Bottled water is a good alternative.

You can use tainted water from tanks to irrigate gardens. You should use alternative supplies until your tanks are cleaned and refilled.

Recreational waters

Recreational waters with large amounts of debris may be unsafe for recreational activities and fishing and foraging of molluscs after fires.

You can find further information at:

• Rainwater and Bushfires - NSW Ministry of Health
• Bushfires and Water Quality - Water Quality Australia
• The Environmental Health Standing Committee’s (enHealth) publication page