A huge, slow-moving rain system is forecast to continue drenching New South Wales, the Australian Capital Territory and northern Victoria today.
Flooding has forced hundreds of evacuations and dozens of rescues.
Three-quarters of NSW was late yesterday under water or at risk of flooding, major dams in Sydney and Canberra were expected to spill - and there is little hope of relief in the next few days.
"This rain band has been an extraordinary event as we rarely see rain of this magnitude in this part of the state, and we rarely see a low trough hang around for as long as this trough's going to," NSW State Emergency Services spokesman Dieter Geske told ABC radio.
While not of the severity of earlier summer flooding that inundated dozens of towns and isolated entire communities, the sheer scale of the unprecedented rain band has stretched resources.