The damage from huge swells that lashed Sydney and much of the NSW coast at the weekend is expected to cost millions of dollars to repair.

Bondi and Clovelly beaches were flooded over and waves up to seven metres high battered the walls of the beachside Coogee Surf Club early on Saturday.

Inside the harbour near the Manly ferry wharf, boats were ripped from their moorings, with some vessels washed up on the nearby beach.

A sailing vessel was spotted capsized at Bronte beach with emergency services launching a search for potentially missing crew.

The search was cancelled after the boat’s owner came forward to say it had been ripped from its dock south at Gordons Bay due to the heavy seas.

The Bondi Icebergs club was also damaged by the wild seas, with both swimming pools to remain shut for at least three days for repairs. The club also lost a clock to the waves.

“As you may have seen, destructive waves pounded the ‘Bergs – and if anyone has seen a huge missing clock, it’s ours” it posted on Facebook on Monday.

University of Sydney coastal geomorphologist Professor Andrew Short told the Sydney Morning Herald that the weekend’s tides were supercharged by a 50-centimetre storm surge in Sydney and an 80-centimetre surge further north in Port Macquarie. He said it would take  “several months to a year” for beaches to recover.

Professor Short also expected more damaging weather conditions, as long as La Nina persisted and the ocean stayed warm.

The Bureau of Meteorology issued a hazardous surf warning for the NSW coast on Saturday as winds calmed in Sydney after a night of huge gusts, including one at 74km/h inside Sydney Harbour.

Across NSW, State Emergency Service crews made six flood rescues in the 24 hours up to 5am Saturday. There were 468 calls for help in the same timeframe.

Elsewhere in the state, flood victims were picking up the pieces for the second time in little over a month.

Byron Shire’s deputy mayor said locals had little warning about the damaging conditions that flooded the region for the second time in a month last week.

Sarah Ndiaye has praised the support offered so far by the state and federal governments but said the poor preparation was the result of Canberra’s cuts to publicly funded agencies such as the CSIRO and Bureau of Meteorology.

“They [the bureau] removed the flood warning from Mullumbimby and said that the weather had cleared so a lot of our community were caught out,” Cr Ndiaye said.

“That was really a shock to people. It was really hard to take after everything we’ve gone through and there’s been so many conversations about where the system failed us in the first place.”

Tweet from @BOM_NSW

She said the community was both exhausted by the double floods and buoyed by the cooperative spirit between people.

The Mullumbimby high school teacher said the area desperately needed short-term to long-term housing fixes as the Easter holidays approached and flood refugees would be forced out of short-term stays.

Her school would remain open but others across the region would be forced to shut, adding even more disruption to the lives of young students who had already endured two years of COVID-19.

“I’m really worried about my community and how we’re going to fare over the next little while,” Cr Ndiaye said.

-with AAP