The Canterbury Earthquake Recovery Authority has announced that 251 residential properties bordering the Avon River in Christchurch have been red-zoned.
The properties, which had been in the orange zone, suffered significant liquefaction and permanent land movement as a result of the earthquake on 22 February last year.
Earthquake Recovery Minister Gerry Brownlee says engineering assessments show that remediating the land might not have worked and that replacing seriously damaged infrastructure would be extremely expensive and time-consuming.
Mr Brownlee says the Government will offer to purchase all insured sections in the newly red-zoned areas.
The rezoning annnounced on Friday involves:
- 78 properties in Central City East
- 29 properties in Linwood
- 144 properties in Richmond South
In addition, one large property near the central city has been zoned green.
'Only feasible option' - Brownlee
Mr Brownlee says consultant engineers Tonkin & Taylor have advised that many houses would have to be demolished in order to address the risk of future lateral spreading, regardless of their damage from the quakes.
"Tonkin & Taylor also advise," the minister says, "that such works would cause substantial vibration, causing further damage to already weakened properties in the vicinity.
"On that basis we've decided the only feasible option is to provide residents with some certainty by offering to buy their land and homes."
A decision is yet been made on the viability of rebuilding 401 orange-zoned properties in the New Brighton suburb of Southshore.
Mr Brownlee says engineers are still assessing that, and a conclusion should be reached soon.
'This is totally political' - resident
Some Avonside residents say they suspect the desire for a park running the length of the Avon has influenced the decision to declare 251 homes near the river uninhabitable.
One of them, John West, says there has been little damage to his own home.
"All the marginal stuff that was orange across the river has gone green," he says. "This is totally political. If the land was really bad it would have been red immediately or it would have been green immediately."