Flood levees protecting the Australian state of Queensland's border town of Goondiwindi are being severely tested as the Macintyre River is closing in on its record breaking flood peak, said a senior hydrologist on Friday.
Ian Rocca said that the Macintyre River was at 10.62 meters and rising.
The expected peak is 10.85 meters, less than 15 centimeters from the top of the levees and above the record 1996 flood level of 10.6 meters.
"The peak will be hanging around for a while. It will peak this morning and stay up for a long time," Rocca said.
Evacuations have occurred in Goondiwindi that has a population of about 6,000 people, and over the border in the smaller New South Wales (NSW) settlements of Boggabilla and Toomelah, which have a combined population of less than 1,000.
Goondiwindi mayor Graeme Scheu said he was confident the flood levees would hold.
"The levee bank is designed for 11 meters. We are expecting this to hold but we are in uncharted territory," Scheu said.
Scheu said the river was flowing fast but rising slowly.
Queensland Premier Anna Bligh said the flood would test the structural integrity of the Goondiwindi levees as the river remains at the peak level for more than 24 hours.
"We assure them everything that can be done to predict and to guarantee their safety is being done," Bligh told reporters.
An evacuation center has been set up at the town's showgrounds and 61 patients and residents from the local hospital and nursing home have been airlifted to the nearby towns of Inglewood and Warwick.
About 3,000 people are in evacuation centers across Queensland and 60 schools and almost 90 kindergartens and childcare centers have been severely damaged or are inaccessible.
The death toll from the south-east Queensland floods disaster stands at 15 after three more men were added to the growing list of victims on Thursday.
The toll is predicted to rise further as more bodies are expected to be found on Friday.
Authorities hold grave fears for 12 people - 11 of them missing from the Lockyer Valley community of Murphys Creek, west of Queensland state capital of Brisbane and most of those 11 from just two families.
Overall, 61 people remain missing.
Floodwaters are receding in Brisbane, where 11,900 homes and 2, 500 businesses are flooded and in Ipswich, west of Brisbane, where 3,000 homes and businesses are affected.