A group of Port Hills residents is promising to take legal action to overturn a decision that forces them to abandon their homes.
Earthquake Recovery Minister Gerry Brownlee announced on Friday that 121 out of 163 Christchurch properties will be zoned red because the risk of rockfall in a future earthquake is too great.
Only five properties will be re-zoned green and 37 will remain zoned white - six in the Horotane Valley and 31 on Bridle Path Road until their properties are properly assessed on 14 September.
Karen Theobald is among a group of 30 Port Hill residents who say they will now take the matter to court.
Ms Theobald says the risk to properties from a rockfall is far less than the Canterbury Earthquake Recovery Authority is claiming and believes her home in Morgan's Valley is safe to live in.
"I just know that what's been done is just and I'm not confident that the information they have used and gathered will be robust enough to support their decision."
Christchurch mayor Bob Parker says the decision gives many people who have already left their homes the ability to move on with their lives.
However, he defends the group's right to test the rezoning in court.
"I think what is really important is that people feel that they have exhausted, either successfully or unsuccessfully, the options that they feel are important to them."
Mr Brownlee told Radio New Zealand's Morning Report programme a large number of the properties are already empty.
The minister says he stands by the decision and is prepared to have the matter tested in court.
Information the Canterbury Earthquake Recovery Authority used to make the decision will be released, he says.