A fire which has been burning in the Warrumbungle National Park in north west New South Wales since Sunday has been declared a catastrophe by the Insurance Council of Australia.

Chief executive Campbell Fuller says the council is sending a taskforce to the nearby town of Coonabarabran today to help people with their insurance claims.

"Their primary goal is to improve coordination between the insurers, state and local governments, emergency services and also local agencies," he said.

Mr Fuller says famers will not be affected if they bury or put down livestock before an assessor can get there.

"Where stock have been injured I'd certainly like to remind residents that they can put down that stock," he said.

"So long as the stock is insured, they notify their insurer beforehand and that they take photographs, collect information about livestock that the insurer may request and record the number and disposal details."

Evacuees were allowed to return home temporarily yesterday.

Local police officer, Mal Unicomb, was among them and says it has been tough to see so many houses destroyed.

"In one word; horrible, many of people are going back to just twisted metal," he said.

"Some have been lucky enough and their houses have escaped the inferno but for many of them, particularly residents out along Timor Road, it's very sad and disheartening."

The Warrumbungle Shire Council says residents will have to wait several weeks before they can begin cleaning up.

Shire Mayor Peter Shinton says police need time to examine the area and prepare a report for the coroner.

"There's going to be issues with asbestos, there's going to be all sorts of things," he said.

"Some houses, the only reason they're there apparently was they got the last dump of retardant put straight on top of the house.

"So that means tanks are going to have to be cleaned out, roofs are going to have to be cleaned, because it's not the sort of thing that you drink, so all that sort of work has got to be done."

He's also warning residents that Coonabarabran's water supply is likely to be contaminated by ash.

"We've got problems with water pumps at our dams, it came over our dam as well," he said.

"We're going to have problems with our water quality as well because the dam now has a skin of ash on it, and soon as we get rainfall, which is predicted for the next couple of days, then we're going to get black water running into the dam as well."

New Danger

The Rural Fire Service says a forecast wind change today could endanger properties south east of the bushfire.

More than 200 firefighters spent another night battling the 42,000 hectare blaze, which has destroyed at least 40 properties.

Paul Best from the RFS says crews will focus on back burning along the fire's edge to protect Coonabarabran's outskirts as well as a telecommunications tower.

"If that does take a run under the coming winds, those isolated properties could come under threat," he said.

"So people in that area should be making preparations, completing their bushfire survival plan and having an idea of what they're going to do over the next few days if that fire does threaten them."

The Bureau of Meteorology says tomorrow's weather conditions are not expected to be as severe as first forecast.

Temperatures are predicted to hit the high 30s and there will be winds of about 25 to 30 kilometres an hour.

Another bushfire burning in the Pilliga Forest, to the north of Coonabarabran, is under control and the Newell Highway has been reopened.