The Earthquake Commission (EQC) has started sending out notices to Christchurch homeowners to confirm whether their properties are at increased risk of liquefaction.
EQC spokesperson Keith Land said last year more than 8,000 property owners were told their land may be more vulnerable to liquefaction following the Canterbury earthquakes.
He said the land had been assessed and the EQC has confirmed about 4500 of those properties were affected.
It will be making payments to people whose property has lost value as a result of the increased risk.