Multimillion-dollar beachside homes in Sydney’s north are still at risk of collapse due to storm erosion.

State Emergency Service crews and hundreds of volunteers worked into the night piling up thousands of sandbags to fortify the dozen or so homes and two unit blocks in Collaroy that are on the verge of sliding into the sea.

The properties survived Tuesday night’s high tide that hit just after 10pm, with SES crews still at the scene on Wednesday.

The Collaroy homes were still in danger of collapsing and residents were not allowed to return home, a SES spokesman said.

Boulders would be brought in on Wednesday to strengthen sea defences.

Meanwhile, as hundreds of New South Wales residents continue the mop-up from the weekend’s monster storms, the SES is concerned gales, due to hit coastal regions on Wednesday afternoon, could cause more damage.

Extremely strong winds are expected to hit the NSW coast just after midday and will continue until midnight, an SES spokesman told AAP .

The winds could send debris flying and also bring down trees already loosened by rain.

SES crews continue to assist residents in the state’s storm-hit communities including around Lismore in the north, areas in Sydney’s south-west including Picton, Milperra and Chipping Norton, and in the city’s northern beaches.



But an SES spokeswoman said the cleanup was now more or less the responsibility of councils and recovery agencies.

The professional volunteer organisation had completed about 10,600 jobs since the storm began, most relating to storm damage, leaking and damaged roofs, and fallen trees.

By comparison, there were 20,000 made during the April “super-storm” last year and about the same during the Hunter floods in 2007.

The spokeswoman said this storm’s point of difference was the extent of the affected area, taking in most of the eastern seaboard and some inland areas.

The most affected in NSW were Warringah and Pittwater, Ku-ring-gai, Sutherland and Wollongong.

During visits to Sydney on Tuesday the prime minister, Malcolm Turnbull, and the opposition leader, Bill Shorten, agreed on an open-ended support package for victims as an insurance catastrophe area was expanded to cover the east coast of Victoria and Tasmania’s northern and eastern coastlines.

The Prime Minister thanks NSW SES volunteers in the flood devastated town of Picton. pic.twitter.com/BR7ISi6NG8 — NSW SES (@NSWSES) June 7, 2016

Sydney’s Northern Beaches council says it will work alongside state government and local residents to build a seawall on Collaroy beach after king tides damaged million-dollar beachfront homes, but won’t foot the entire bill.

Up to 12,000 sandbags have been piled up against properties on Pittwater Road overnight in an attempt to reinforce damaged buildings, with residents forced into emergency accommodation until engineers can assess the damage.

“The residents will need to contribute something ... the ratepayers should not necessarily have to foot the total bill for private benefit,” said the Northern Beaches council general manager, Mark Ferguson.

• Australian Associated Press contributed to this report