The Bureau of Meteorology (BOM) has described the floods that hit the New South Wales north coast three weeks ago as a "one in a thousand year event".
BOM has been criticised for failing to warn residents of the magnitude of the flood, but national manager of flood forecasting Jeff Perkins said the bureau could not have done more.
"This was an extraordinary event. It was a record flood at Murwillumbah," he said.
Mr Perkins said despite forecasting much less rain than actually fell, the bureau had put out warnings two days prior.
"We took every step we could to warn the people of the Tweed," he said.
"We started putting out flood watches for the Tweed Valley as far back as Tuesday lunchtime.
"We issued our first warning for the Tweed Valley at 7:00am on that Thursday morning and we issued our first major warning at about noon for the Tweed and for Murwillumbah."
Mr Perkins said the heaviest rainfall had been overnight on the Thursday and Friday, which fell in addition to the 200-400mm that had already been recorded.
"The bureau updated its warnings every three hours and in all the warnings we were saying that we were expecting major flood levels, but higher levels were possible because the rain was still falling," Mr Perkins said.
Farmers concerned about lack of warning
Dairy farmer Pat McDonald watched his milking shed and pasture paddocks flood and was deeply distressed by the lack of advice on the radio about river heights, which many consider the best indicator of a coming flood.
"I've had experience all my life with floods and this year we got caught with insufficient notice, and it's not just my story," he said.
Cane farmer David Bartlett knew the flood was coming, but still got caught by surprise.
"We packed everything up, put our tractors away, did everything we were supposed to do for that sort of flood event," he said.
But he said it was not enough, because the flood was much bigger than had been forecast.
"In the dead of the night people started to realise, there's water where there's never been water before," Mr Bartlett said.
"They got out of bed and put their feet on the ground and the water was already in their bedroom."
Flood caught residents by surprise
There were signs it was going to be a bigger flood event than BOM was forecasting.
On the morning of the flood, SES volunteer Lloyd Martin was plotting the height of the three rivers that flow into the Tweed, and comparing them to previous floods.
"We looked at what the weather bureau was saying … and it was too low … so we gave them a phone call," he said.
"As a result of that they put out an upgraded forecast and it was much closer to the mark."
The flood caught people by surprise partly because it built up overnight in the Tweed River and then, in the early hours of Friday morning, it broke through at a point just outside the town — the Black Strain drain next to the Poinciana Motel.
Mr Bartlett said it had never broken through there before.
"It's taken the Tweed Valley Way out, about two and a half to three metres of bitumen, gravel, solid road, even the sewage main, just wiped the whole lot out," he said.
A wall of water hit many businesses in the south Murwillumbah industrial zone, damaging millions of dollars worth of stock and equipment.
Massive flood losses
Anni Brownjohn runs the Right Food Group and she lost $2.5 million in organic food.
She estimates the flood damage to the businesses in the area would be close to $25 million, and said 500 jobs were at risk if those businesses went under.
She hoped the Government would fund a massive infrastructure plan to prevent that from happening.ABC