Rosie Crerar Photo: Freddie Bonfanti

An ex-Goldsmiths student was among those fleeing Brisbane as the Queensland city faced its worst floods for 100 years, and tens of thousands were urged to evacuate their homes.

Rosie Crerar, 29, has been travelling in Australia with her boyfriend Freddie Bonfanti, 27, since December 1. The pair arrived in Cairns and were planning to slowly make their way down the 1600-mile stretch of coast towards Sydney.

But their travel plans were disrupted after a cyclone hit the Queensland town they were staying in on December 20. Since then they’ve been driving south, aiming to avoid floodwaters as torrential rain hits Australia’s east coast.

They thought they had avoided the floods by travelling to Brisbane but woke on Tuesday morning, after only two days in the city, to hear that an “inland tsunami” had hit Toowomba, a town 70 miles to the west, killing 12 people and leaving more than 40 missing.

Ms Crerar said “word of mouth had exacerbated things and people were panicking.”

“We left at about midday Tuesday. Crossing the river, you could see how high it was. The rain has been torrential – it’s not British rain, it’s monsoon rain. The big fear is that there are snakes and crocodiles in the floodwater.”

Queensland Premier Anna Bligh declared three-quarters of the state a disaster area yesterday and said the death toll was likely to rise: “We have to face the fact that there will be very grim news as we continue the search and rescue. We must brace ourselves for a significant death toll.”

She said the floods were “the worst natural disaster in our history”, as officials warned that the worst was yet to come.

Julia Gillard, Australia’s Prime Minister, said she was “bracing for further bad news”, calling the devastation wreaked by the floods “shocking” and “mind-boggling”.

Glaswegian Ms Crerar, who studied English and comparative literature at Goldsmiths College and lived in East Dulwich before going to Australia, has now reached Sydney, where she plans to stay for the next year.

“We’re just watching Brisbane on the news now,” she said. “Museums and places that we were in on Monday are completely flooded.”