Towns are cut off and residents have been evacuated in military planes during “the worst flooding Western Australia has ever seen”.
Authorities are working to let remote Aboriginal communities in the Kimberley region know of the danger, to relocate those who want to leave and deliver critical supplies. Derby, Broome and Noonkanbah have already been isolated.
Heavy rain dumped by ex-tropical Cyclone Ellie led to once-in-a-century flooding around Fitzroy Crossing, forcing the evacuation of the remote town as well as dozens of Indigenous communities.
The WA emergency services minister, Stephen Dawson, said on Thursday that the “situation is still changing”.
“It’s proving to be extremely challenging for residents in the region,” he said.
Once the water recedes and the scale of the damage is known, the state is likely to seek more support from the federal government, which is providing financial help as well as three Australian defence force planes to move people and supplies.
Residents were experiencing “the worst flooding WA has ever seen”, Dawson said, adding that it was “deeply distressing” for people who had lost livelihoods or livestock and seen animals injured.
The Bureau of Meteorology’s WA manager, James Ashley, said the water at Fitzroy Crossing peaked on Wednesday at 15.8 metres and was slowly receding – but other places were at risk.
“That peak is moving downstream … there’s a lot of water moving downstream,” he said.
“Winds and rain will increase again across the area. It’s likely to be shorter-lived and the contribution of rainfall to the flooding is likely to be minimal. The system looks like moving out of WA and into the Northern Territory over the weekend.”
The fire and emergency services commissioner, Darren Klemm, said authorities had shown remote Aboriginal communities modelling of what might happen if the water reached 15 metres near them. But he emphasised there would be no mandatory evacuations.
Klemm said elders were being consulted about the cultural needs of anyone who did leave.
“That’s a decision for those people to make,” he said. “We just want to make sure they’re safe, they have food and water and any medication they need.”
Flooding forced authorities to close a 700km section of the Great Northern Highway between Broome and Halls Creek, isolating Derby, a town of about 3,000 people.
The highway is the only road transport route to the north of the state and it is likely to be cut for months after a major bridge suffered significant damage at Fitzroy Crossing.
Damage to the Fitzroy River bridge is still being assessed.
About 60,000 cubic metres of water a second was flowing down the swollen waterway, according to the Bureau of Meteorology. The river snakes its way to the coast at Derby, north of Broome.
Earlier on Thursday, the federal emergency management minister, Murray Watt, said RAAF planes were having difficulty getting to the area.
“In the meantime, the Western Australian government has been able to source some of its own aircraft and relocate people,” he told ABC radio.
Authorities are particularly worried about 50 remote Indigenous communities outside Fitzroy Crossing, comprising several hundred people.
“We’re concerned about the risk of isolation, potentially for weeks, for those communities,” Watt said.
“There will be people who don’t necessarily need to be relocated, but will have some issues obtaining food, vegetables, all sorts of other things and it will be important to make sure that we can resupply those kinds of communities.”
Fitzroy Crossing’s evacuation centre in the town of about 1,500 was at capacity on Wednesday, with plans to open another. The flood waters aren’t expected to fully subside for weeks.
The town’s supermarket and numerous homes have been inundated and only a few streets remain above water, with people, livestock and wildlife clambering for dry ground.
Pastoralists and livestock have also been significantly affected by the flooding, but the extent of the losses won’t be known until the water recedes.
