Esther Oliver's house backs on to a creek in Brisbane, Australia's third-largest city and the capital of the beleaguered state of Queensland. Last Wednesday, Ms Oliver, a former teacher at a Jewish school in Melbourne who sits on the Queensland Jewish Board of Deputies, looked on anxiously as the flood waters began inching towards her house. When it started flooding her garden, she began to panic.

"I was watching it coming. It was seeping. I fully expected it to flood the house. I expected snakes. I was scared."

Knowing the likelihood of damage, the mother of three moved her furniture upstairs. "The creek came to the house and then stopped. I was so lucky. I have never seen a natural disaster like this one."

She is one of dozens of Jews affected by what has been dubbed "a flood of biblical proportions" that ripped through Queensland last week, killing at least 20 people, with at least 12 others still missing.

The floods - described by Premier Anna Bligh as the "worst natural disaster in our history" - prompted Prime Minister Julia Gillard to deploy the army to aid the rescue effort. More than 75 per cent of Queensland - an area approximately five times the size of the UK - was declared a disaster zone. The Queen and Prince Charles have made private donations and the Pope is holding a special public mass.

On Monday, the Commonwealth Chief Rabbi, Lord Sacks, wrote to David Paratz, former president of Queensland's Jewish community, offering his sympathy. "We share your grief, your trauma, your tears," he wrote. Ari Heber, of Queensland Jewish Community Services, was the contact point for the community's 6,500 Jews. "Now we have a committee dealing with the situation but for the first few days it was just me," he said. "We had a first request today for financial assistance from a family whose apartment was destroyed and who had no insurance. We're expecting that from a few other Jewish people as well. One family living in a rental place is not even bothering going back. Everything is gone, they've lost everything.

"A few families don't want to talk. It's extremely surreal. It's devastation. The roads are covered in brown mud. Everyone's emptied stuff onto the street. Everything is brown and it stinks."

He said post-traumatic stress could be a big problem. "I've started putting together a mental health programme with psychologists and psychiatrists," Heber added.

Queensland Jewish Board of Deputies president Jason Steinberg agreed. "Trauma - that's the thing that will reveal itself over the coming weeks. Once the mud is out of the houses they'll think, where do we start our lives?"

In an email update, he said: "At this stage, we know that seven-plus families have lost their homes and businesses; there are still seven-plus homes without power and there are a few families still isolated in their homes." There was no damage to the Jewish institutions: two Orthodox synagogues, two Progressive temples, a Jewish school and a kindergarten. But the community's most urgent needs were generators, vacant rental accommodation, spare business space and storage space.

"From the Jewish community's perspective a lot of people have great networks. Now the clean-up starts in earnest," said Steinberg, 42, who was plunged into the polluted Yarkon River before the 1997 Maccabiah Games, which killed four Jewish Australians. "From a leadership perspective I was on the bridge that collapsed so I've been involved in that significant disaster and various other crises.

"The really heartwarming thing is the number of Jewish community members who have requested to volunteer."

Among those who are not insured are Howard and Rosa Rother, who live in the small town of Toowoomba, close to the epicentre of the flood, where mass graves are being dug to bury dead livestock. Although they have a house in town, they also own a 500-hectare cotton and corn farm.

"We're OK, the farm was affected more than our house. We could have lost 60-70 per cent of our income," said Howard Rother, who moved from America to Australia in the 1960s. "In my 30 years of farming this is probably the worst in terms of flood damage."

Gary Goldman and his wife Miriam missed the flood because they were in Israel at a barmitzvah. They anxiously watched the events unfold on TV.

"My house backs onto the Brisbane River. It's eight metres up to the house. The water came one metre inside our first storey."

He and his wife's elderly parents helped move belongings upstairs before the flood peaked last Thursday. "Our house is a shattered mess. A lot of people have come to help us. A guy came from the Gold Coast, about 45 minutes drive away. I've never seen him before and probably will never see him again. He just shovelled mud for hours."

Efrat Sudai, 31, an Israeli living in a ground-floor flat in Brisbane, was evacuated. "The water came all the way through the floorboards, the whole place was flooded. We managed to pack most of our stuff and get it out, but there's damage to walls, floorboards, carpets, and a lot of mud and mould."

She said her family in Tel Aviv was "petrified" watching the harrowing images on TV.

Brisbane Hebrew Congregation's Rabbi Levi Jaffe took no chances before the flood peaked. He took four Torah scrolls from the shul and drove them to his house, where he held services last Shabbat. The water came within 50 metres of the 125-year-old synagogue. He also helped a couple evacuate from their high-rise inner-city apartment.

"We're trying make sure we can help everybody who needs help. Hopefully next week we'll be back in business."

Jewish communities around Australia are rallying in support of their compatriots. Rabbi Moshe Loebenstein of the Melbourne-based Chabad of Rural and Regional Australia said he was organising Melbourne and Sydney families to host affected Jewish families and was sending up dry goods, clothing and towels. A Chabad kitchen in Sydney has prepared food packages to send north. The Sydney-based Jewish House Crisis Centre is holding a fundraiser for the community while Jewish Care and other welfare organisations have offered assistance and advice as Executive Council of Australian Jewry president Dr Danny Lamm urged the 110,000-strong Jewish community to "dig deep" to help those in need.

Queensland faces a long road to recovery. But out of the tragedy there is hope. "The atmosphere here is amazing," said Esther Oliver. "There is a mountains of rubbish. There's a rotten food problem, there are rats, people have had snakes going into their homes. I've been helping out on dinners at the Salvation Army feeding strangers.

"But people here have been astonishingly helpful and open-hearted. It's been remarkable to see the spirit of goodwill. It's an unfortunate way to find out how good the Jewish community is."