Losses from the flooding catastrophe in NSW and southeast Queensland have reached $385 million, the Insurance Council of Australia (ICA) estimates as improving conditions allow clean-up and support efforts to accelerate.

ICA says the disaster has resulted in 25,681 claims to date and insurers expect numbers to rise over coming days as more people return to their properties.

IAG CEO Nick Hawkins says the insurer is "working hard providing support to customers and communities affected by flooding”. 

“Our teams are on the ground supporting customers in the worst impacted areas of the NSW Mid North Coast, Western Sydney and south east Queensland, assessing the damage to our customers’ homes, ensuring their properties are safe and arranging temporary accommodation for those who need it,” he said today.

IAG estimates its net cost from the event at approximately $135 million, based on exposure, claims lodged to date and experience with previous similar events. The total is estimated at $200 million pre-quota share arrangements.

The insurer estimates the event will push financial year net natural perils claim costs to about $660-700 million, exceeding the perils allowance of $658 million for the period.

Suncorp said yesterday it will update the market on expected claims costs once numbers stabilise and it can more accurately estimate the ultimate number likely to be lodged.

As of 4pm Wednesday, Suncorp had received just over 5400 claims across NSW, Queensland and Victoria, with 80% of those from NSW. More than 85% of total claims relate to property damage.

CEO Steve Johnston says support teams are being deployed in affected regions as it becomes safe and are helping with arranging emergency repairs, organising temporary accommodation for customers whose homes have been severely damaged and providing cash payments for emergency purchases.

“The next few weeks will be challenging for residents as they return to their homes, assess the damage and start the clean-up,” he said.

The state government says it has established a multi-agency strike force comprising the Australian Defence Force, NSW Rural Fire Service and Fire & Rescue NSW, and is drawing on lessons learned from the bushfires last summer.

“Our priority right now is to ensure roads are accessible, places are safe for people to return, and to assist with washout and clean-up by removing bulk waste,” Deputy Premier John Barilaro said.

The Bureau of Meteorology warns many rivers across NSW remain in flood despite improved weather.

Moderate flooding has continued along the Hawkesbury River at North Richmond and Windsor, while flooding fell below the moderate level at Wisemans Ferry yesterday. Water levels are forecast to continue receding into the weekend.

Over the past seven days nearly 75,000 gigalitres of water has reached the ground in NSW, 150 times the volume of Sydney Harbour, the bureau says.