7 Nov 2013

Residents reassured despite land risk

6:13 am on 7 November 2013

People living in Christchurch's Port Hills are being reassured they don't need to leave their homes, despite some houses posing a risk to life if there is a major rain storm or other extreme weather event.

The Christchurch City Council on Wednesday released the first of a series of reports commissioned from Geological and Nuclear Sciences Ltd (GNS) about stability in the Port Hills.

The first report identifies 36 areas containing 700 homes where there could be further land movement as a result of damage caused by earthquakes since 2010.

Some 134 of those properties are in areas including Redcliffs and deemed as Class 1, which means that land movement could lead to the loss of life, and homes and critical infrastructure could be severely damaged.

Many of the most at-risk houses have already been zoned red (are uninhabitable) by the Government, but 53 are in the green zone and people may still be living in them.

John Ryder owns one of the properties in the green zone and says he won't rebuild there because it would be dangerous. He hopes the land will be re-zoned red so he can get paid out for it.

The council said on Wednesday that the threat is not imminent and it has no plans to move anyone out. Its general manager of strategy and planning, Mike Theelan, said there is a geotechnical team monitoring the land.

"At this stage, the information we have tells us there's a potential risk ... but it doesn't suggest to us that there's a level of risk that meets that test that there's an imminent risk of failure in the land."

Mr Theelan said the type of event which could spark land movement could be a large quake, extreme rain, heat, snow storm or leaking pipes.

"The bigger risks that will trigger land and stability issues are things like very wet winters, equally very dry summers where you get some cracking in the land, cracking in the soil, but greater chance for water incursion as well."

Tony Aldridge planned to start rebuilding in Quarry Road in Mt Pleasant at the start of the year, but on Wednesday learned that it is in the Class 1 zone.

"It's been well over a year since we signed for a rebuild. We expected to be building in February this year ... we'll battle a bit longer."

The council said it has been in touch with all affected homeowners.