Investigators are probing how firefighters came to douse parts of a West Australian town in sewage wastewater while battling a bushfire.
Residents in Bullsbrook, about 35km north-east of Perth, have been warned to empty water tanks and not eat anything from their gardens after water bombers drew from the wrong ponds at a wastewater treatment plant on Wednesday when battling a blaze that was threatening homes and schools.
Officials are probing why the ponds were not marked as no-go zones in department logbooks.
“Department of Fire and Emergency Services (Dfes) maintains an extensive log of no-go zones for water sources throughout the state,” a spokesperson said on Friday. “A review of the status of all available water sources in the state will be conducted.”
Dfes said one of the ponds contained a safe water supply “however it was later discovered the two other nearby ponds contained wastewater”.
A Hazmat warning was issued for an area including the local high school which remained closed for cleaning on Friday.
Bullsbrook resident Natalie Bennett said her family was hosing down their roof when they were showered by helicopters passing overhead on Wednesday.
“When they flew over us leaking [water], at the time it felt lovely as it was so hot,” she told Guardian Australia.
Bennett said she was horrified to receive a text on Thursday at 2am local time about potential exposure to hazardous bacteria.
“Regardless of the grossness and possible danger from the Hazmat, we are eternally grateful to all the fireys who saved our homes, the school and the doctor’s surgery. It would not have been possible without the choppers’ fast turnaround.”
The WA health minister, Amber-Jade Sanderson, said the sewage water was not dropped directly on homes and the risk of contamination was “very low”.
“Obviously this is a mistake, it was found early, and an emergency meeting was called and public health have been called in and are involved in remediating that issue,” she said on Thursday.
“There’s a range of advice for people, including if you have a water tank, you should empty that water tank. If you have fruit and vegetables, don’t pick them in the next 48 hours and wash them well.”
The state premier, Roger Cook, said there may have been some drift spray that could have impacted the local community and the department was reacting with an “abundance of caution”.
“Our priority is to keep people safe and get the fires out and in emergency situations sometimes it doesn’t always go to plan, but the water which was contaminated was dropped on a bushland area,” Cook said on Thursday.
Dfes said firefighters had been advised to monitor their health and see a doctor if symptoms developed.
A United Professional Firefighters Union of WA spokesperson said firefighters who were working on the blaze from the ground were not informed of the mistake until 7pm on Wednesday.
“They were already at home having dinner with their families. If it is not a problem, then why have officials put out a Hazmat warning?” the spokesperson said.
The union was investigating if any of its personnel were feeling unwell.
Emergency WA said on Friday afternoon the Bullsbrook bushfire was “contained and controlled”.
