Heavy rain soon after bushfires can potentially degrade the quality of your tank water. You may find windblown ash, debris, dead animals or fire retardants have affected your rainwater tank when returning home after a bushfire.

If you haven’t already done so, disconnect the down pipes from your tank. The first rainfall after the fire should be run to waste, if the roof has not been cleaned.

Clean your roof to remove ash and debris, if this can be done safely.

Check your roof and guttering for dead animals and remove if present.

Water testing is usually not necessary, as contamination is obvious.

If the water is contaminated the tank should be drained, cleaned and refilled. Working inside a tank can be very dangerous.Professional tank cleaners are available in some areas.

Filters and other water treatment equipment could be affected by debris. Refer to the manuals for your equipment or seek advice from the supplier on responding to problems.

After drinking water has been captured or delivered, flush taps in the property to bring through the new clean water from the tank.

Your tank water may also be contaminated if:

the tank has been burnt by fire and/or the internal lining material is damaged

the plumbing to or from the tank is damaged

the water level has increased due to water bombing.

The presence of ash and debris in rainwater is unlikely to be a health risk, but could affect the appearance and taste. Fire retardants currently used in Australia are of low toxicity, but may also affect the appearance and taste of rainwater.

Disinfection and filtration of tank water.

To be 100% sure of your water supply we would recommend that the water in each case be tested by a certified laboratory before drinking, including testing for Arsenic and Chromium.

For sediment/ash removal, we suggest a 5 to 20 micron sediment filters, and for smoke smell/taste we would recommend a carbon cartridge.

In addition to filtration we recommend treating your tank water due to potentially increased bacteria in your supply. Odour and discoloration are the main signs you my have bacteria or organic matter in your tank. Davey Acquasafe is a rain tank purifier that can kill up to 99.9% of all germs, bacteria and viruses in your rainwater.

We would also point out that filters may need to be changed more frequently, due to the higher than usual content of contaminants.