An independent review of the NSW government’s response to the state’s flood crisis will determine what mistakes were made and what can be improved, the emergency services minister says.

“I think we can always do better next time,” Step Cooke told Sydney radio 2GB on Monday.

There are now 8000 Australian Defence Force personnel in NSW ensuring supplies reach communities that are still cut off by floodwaters, as well as helping with the massive clean-up operation.

However, there has been criticism of how long it took to deploy troops to help with the crisis and questions are being asked about who is to blame.

SES commissioner Carlene York has also faced questions about why civilian rescue helicopters were left grounded across the state as floodwaters inundated the Northern Rivers.

Ms Cooke says all aspects of the emergency services response will be examined, adding it’s a complex issue.

The review will determine why it took so long to get troops on the ground in the Northern Rivers to help thousands of people whose homes were inundated with flood waters.

“The deployment of ADF troops is something that will be considered as part of that review,” Ms Cooke said.

“If there are ways that we need to do things differently in the future to ensure that our communities have the maximum amount of notice to prepare and our response is timely and is where it is needed, when it is needed, then that is something that will benefit communities right across NSW.”

Ms York says worse than forecast weather explained why civilian rescue helicopters were not called to help with the crisis.

Emergency crews were only expecting minor to moderate flooding in the region; less than had inundated the north coast last year.

“We resourced appropriately on those levels,” Ms York said on Sunday.

Instead towns were hit with record floods, including in Lismore where waters were two metres above any event recorded.

Helicopters were meanwhile deployed to areas like Cooma, near the Snowy Mountains, to be on standby for floods that never arrived.

Ms York said the worst of the floods in the Northern Rivers had hit at night when rescue crews were restricted in what they could do.

Meanwhile, the SES has determined 3396 homes are uninhabitable and 6708 were inundated as 120 motor homes were last week on their way to the Northern Rivers to deal with a drastic shortage of accommodation as part of a $551 million housing support package.

The NSW government has set up 10 recovery centres to provide access to services while $25 million will be spent on mental health support.

The latest two recovery centres will open to flood-affected communities on the Central Coast at Spencer and The Entrance to help communities transition from response into clean-up and recovery.

Moderate flooding has been recorded at Tuggerah Lake while major flooding remains current in the lower Hawkesbury River.

An evacuation warning remains in place for over 500 people living at Spencer and Gunderman and the SES  is advising residents to take action now to prepare for the floodwaters

The federal government declared a national emergency  NSW late on Friday, which will speed up access to stockpiled resources and financial aid to flow faster.

Residents of a dozen councils area in NSW are eligible for disaster funding, with one-off payments of $1000 per adult and $400 per child available for those affected.

Workers, businesses and farmers who lost income can also apply for 13 weeks’ help.

The Insurance Council of Australia estimates more than 126,000 claims across Queensland and NSW will cost insurers $1.89 billion but concedes further claims are likely.

– AAP