The owners of 34 properties in the Bay of Plenty town of Matata will be forced to abandon their homes and land after the local council voted it isn't safe enough for them to stay.

The Whakatāne District Council voted nine to two to go through with the plan to declare the houses unliveable, 12 years after debris flow wrecked the town.

A torrential downpour washed boulders, logs and other debris down the flooded Awatarariki Stream in 2005, destroying homes and racking up a bill of $20 million.

After twelve years, the council decided it's safer to clear the area.

In 2012, property owners were told a debris net would not make the homes sufficiently safe.

Scientific work carried out since then confirmed that there was "considerable risk" to people remaining in their homes.

Mayor Tony Bonne, who cast his vote in favour of the proposal, says it hasn't been an easy decision to make.

Mr Bonne says the Bay of Plenty Regional Council will have to sign off on the decision but he expected it will approve the plan.

He says the council will also work with central government to buy out the affected properties.

Council offers for properties 'ridiculous - homeowner

Marilyn Pearce's home was damaged by debris in 2005.

She told Checkpoint with John Campbell she would have left then if the council had said it could not mitigate future damage.

"The values of the property were actually higher than what the dam was going to cost, so they said 'no, we'll do the dam'," Ms Pearce said.

"They told us we can build, they were going to mitigate the risk."

She said she rebuilt in 2008 after getting council, EQC and insurance approval and thought everything was fine, up until about 2009 when things started to change.

"They were going to mitigate right up until 2012.

"We had already built by then, we were back, we had all our land looking nice, landscaped - everything, we had moved on."

Ms Pearce says in 2012 the decision came down that there was no viable engineering solution.

She has now been offered $600,000 for property and she was not happy.

Ms Pearce said she was not going anywhere, and that she was not the only one.

"Their offers are ridiculous. If they want the land that bad they can pay for it.

"This is not voluntary, this is actually a forced acquisition. We're not red zoned, we've never been red zoned."