Moving people out of flood-prone areas in north and south Lismore could cost $400 million, and the local council can't afford to pay its share.
Lismore City Council general manager John Walker said state and federal funding would be essential if a strategy of planned retreat was pursued.
"In voluntary buy backs there has traditionally been a requirement for councils to cough up a third of the cost," he said.
"That's just not possible for us."
Building back better?
The council hosted a Building Back Better community meeting this week to get feedback on a discussion paper it released three weeks ago.
A planned retreat option generated the most discussion.
An online survey, to which 91 people responded, showed strong support for the idea of a voluntary land-swap or buy-back scheme that would allow residents in the most flood-prone areas to move to higher ground.
Among those in favour was Berri Drum, whose South Lismore home was inundated just three days after she bought it.
"I'd like to get moved onto high land," she said.
She said she loved her house but didn't want to go through another flood.
Mr Walker told the meeting there was suitable land available, with an estimated 3,500 blocks in the development pipeline.
He said the council was still in the process of community consultation, with a number of other options also on the table.
They included relocating the city's golf course to make way for a new commercial and mixed-use centre, and rezoning new areas for medium-density residential development.
Suitable land has been identified in areas including the North Lismore plateau, Goonellabah and near the Southern Cross University.
Big spend needed for rebuild
Government money has been flowing into the region in the wake of the floods.
NSW Flood Recovery Minister Steph Cooke said more than $3 billion in support, mostly split 50:50 between the Commonwealth and NSW governments, had been announced since the first disaster declarations were made.
Mr Walker said it would make sense for both levels of government to back a one-off land-swap scheme rather than risk similar payouts into the future.
"We saw during the week how the Queensland Government put $700-odd million on the table, and we have a desperate need," he said.
