Some 225 Christchurch homes are at risk from rockfall following February's earthquake, a geologist warns.
The 6.3-magnitude quake has severly damaged homes and buildings in many parts of the city and caused land to become unstable.
Loose rocks are being removed from cliffs in parts of Bowenvale, Avoca and Heathcote valleys, Redcliffs, Sumner, Lyttelton, Rapaki and Governors Bay Road.
Geologist Mark Yetton expects this work will save all but 50 properties. Those homes will have to be abandoned, given the proximity of the newly discovered active fault-line.
Owners of the other houses should be able to return within eight weeks, Dr Yetton says.
However, he warned that people living near the cliffs would not be allowed to remain in their homes if they were in danger.
Some houses on five streets in Clifton Hill and at Redcliffs, McCormacks Bay and Rapaki may also be susceptible to landslides.
Geologists are assessing these areas.