Canterbury Earthquake Recovery Minister Gerry Brownlee announced this morning that 121 of the remaining 163 white zone properties would be rezoned red and only five properties would be rezoned green.
All property owners were told of the decisions last night.
A further 37 properties would remain zoned white because mitigation analysis had not been completed.
Mr Brownlee said the decision to rezone 121 properties red was based on the ongoing risk, as well as an analysis of options surrounding mitigation.
"Experts have looked at a number of mitigation options taking into account a wide range of factors, including timeframes for implementation, disruption to residents, and engineering and economic viability.
"It is not considered to be practicable to implement mitigation in these areas, and it should be remembered that nowhere in the world has mitigation for potential rock fall due to earthquakes ever been used," Mr Brownlee said.
