Drones proposed for red-zone demolition
Remote-controlled machinery, water-blasters, drones and controlled explosives are being considered for the demolition of red-zoned Port Hills properties.
A statement from the Canterbury Earthquake Recovery Authority (Cera) released today revealed a variety of innovative tools were being explored for the complex task of demolishing damaged homes on Christchurch's hills.
Cera chief executive Roger Sutton said the Port Hills work was "very challenging" because of the difficult terrain, access and natural hazards.
Cera was working with the Christchurch City Council, contractors and other experts to find the best way to handle the work.
Potential options included using remote-controlled machinery, large water-blasters and controlled explosives.
Cera was also exploring the option of using drones to collect demolition-specific data.
"In considering the method of demolition for a property on the Port Hills, there is a wide range of criteria - about 100 separate considerations - that much be addressed before approval can be given."
Properties that might look like obvious priorities for demolition, such as homes teetering on cliff edges, were among the most dangerous and required the most work to coordinate, Sutton said.
"We are very mindful of not only the risk posed to those carrying out the demolition but also how it will affect any neighbours and the wider neighbourhoods, and the geological effects."
Insurer-led demolitions were due to begin at red-zoned homes owned by the Crown in Morgans Valley and Avoca Valley roads from Monday.
Contractors would have to manage rockfall hazards at both sites and freight containers would be in place to act as safe zones for workers, Sutton said.
Escape routes would also be identified at each site, and spotters would be watching for any warning signs of impending rockfall.
The Government has purchased 304 Port Hills properties to date, with a further 101 under offer.
Red-zoned property owners have until August 31 to decide whether to accept the buyout offer.