Premier Mark McGowan says receding floodwaters in WA’s Kimberley have exposed an “extraordinary” level of damage that could take months to repair.

Roads to badly ravaged Fitzroy Crossing remain cut off by floodwaters up to 50km wide, with only helicopters and small planes able to land at the airstrip.

And the outlook for the summer is grim, with the northern region’s drenching wet season yet to hit full impact in February.

Mr McGowan said the record-breaking flooding had caused extreme destruction.

“The damage to the roads and bridge is extraordinary, and will take a long time to fix,” he said.

“This is an issue we’re going to have to manage for months, if not longer.”

Desperate residents of Fitzroy Crossing have been forced to sleep rough as a sodden runway slows the delivery of essential aid.

“One of the challenges has been the capacity to get the large planes into the airport,” Mark Anderson, Foundation for Indigenous Sustainable Health chief executive, told AAP.

“The airstrip was covered by water for a week … It still looks like an ocean on the edge of the airport.”

The foundation is working with the WA government to deliver non-food essential supplies, like bedding, clothing and cookware to residents who have lost everything.

It’s only been able to get four pallets of goods into the town in two days and was forced to ration supplies in the town, with many people turned away.

“We could only give two towels to each family group and we were getting houses that had 15 people living in them,” Mr Anderson said.

The slow arrival of the aid has meant some families, including children, are forced to sleep on the ground after the floodwaters destroyed their beds.

Others only have the clothes they are wearing.

“This young couple came in with their disabled daughter and the only thing we could give them was one fitted sheet,” he said.

“We didn’t have any mattresses left and they were sleeping on the floor with their little one in a house of more than 10 people.

“There was nothing I could do.”

Mr Anderson said the group had hoped to send 15 pallets of supplies from Broome to Fitzroy Crossing on Tuesday but authorities have said the runway remains too wet to land a large plane.

“We can only get 2.5 pallets in now,” he said.

Prime Minister Anthony Albanese said the disaster relief operation was a “massive logistical challenge”.

“You have places like Fitzroy Crossing but also Derby, as well as a range of other very small, remote communities, being cut off, that the roads aren’t usable,” he told ABC 7.30 on Monday.

“The bridge into Fitzroy Crossing has basically been destroyed, so the only way that goods can be got in at the moment is by air.”

The Australian Defence Force has increased its support to the aid effort with 200 personnel, three fixed-wing aircraft and five helicopters on the ground or set to arrive on Tuesday.

Mr Albanese and Premier Mark McGowan toured the devastation and met with residents at Fitzroy Crossing.

Flood victims can now apply for commonwealth emergency relief payments, with individuals eligible for $200 each, up to $800 per household.

Financial assistance is also available for house repairs and contents replacement up to $10,000.

Emergency Management Minister Murray Watt said the clean-up and rebuild and repair job would take a long time given the remote location and shortage of tradespeople.

“No matter where you are, whether you’re in the middle of Sydney or remote Western Australia, there is a shortage of tradespeople at the moment, but it actually is more complicated, obviously, in remote areas,” he told ABC radio.

The Albanese government opened applications for its Disaster Ready Fund on Tuesday, which will allow state and territory governments to apply for up to $200 million a year in federal funding to assist with disaster mitigation.

“That sort of money could be used for things like evacuation centres, or it could be floods levees, drainage improvements, bushfire breaks,” Mr Watt said.

– AAP