5000 Auckland buildings could collapse in quake

The Christchurch earthquake has prompted Auckland Council to assess pre-1976 structures over the next four years at a cost of $2.3 million. Photo / Mark Mitchell

Auckland has more than 5000 old buildings that could collapse in a moderate earthquake.

The Auckland Council yesterday disclosed the scale of earthquake-prone buildings throughout the region.

Last month, it issued a preliminary list of 393 in many of the city's old town centres.

Because of the Christchurch earthquakes, the council has drafted an earthquake-prone building policy which indicates that more than 5000 structures built before 1976 will be assessed over the next four years at a cost of up to $2.3 million.

The first buildings checked to see how they will fare in a moderate earthquake are 275 that would be needed in a disaster, such as hospitals, police stations and emergency centres.

They will be assessed by the end of the year and will have to be strengthened within 10 years.

The next priority is 480 buildings used by large crowds, such as airport terminals, schools and cinemas. These will be assessed by the end of next year and require strengthening by 2022.

Council building control manager Bob de Leur said up to 4500 predominantly unreinforced masonry buildings that could be assessed by the end of 2015.

Owners would have until 2045 to strengthen these buildings.

The council was also assessing 11 essential pieces of infrastructure, such as dams, and 131 buildings on reclaimed land in downtown Auckland at risk of liquefaction.

The policy, which will go out for public consultation, aims to balance the cost to building owners against the low risk of an earthquake in Auckland.

In 2006, an Institute of Geological & Nuclear Sciences report said the risk of a serious earthquake in Auckland was low.

Mr de Leur said Auckland would not suffer from a lot of liquefaction like Christchurch because it had different soil types with a large volcanic layer.

The previous list of 393 buildings in the former Auckland City area revealed many hot spots in old town centres built in the late 19th and early 20th centuries, including Mt Eden, Kingsland, Balmoral, Mt Albert, Mt Roskill, Epsom, Remuera, Parnell, Ponsonby, Jervois Rd, Karangahape Rd, Queen St and the central city.

As officers did a field survey to check the accuracy of the seven former territorial councils, 2700 buildings, such as farm buildings, parking buildings and small structures, were identified in lower priority categories.

DANGER LIST

* Essential infrastructure, such as dams: 11

* Emergency services, such as hospitals: 275

* Buildings housing crowds, such as schools: 480

* Other commercial buildings*: 4500

* Total: 5266

*Approximate number