Shuddering in Wellington

23:00, Mar 17 2011

Christchurch's deadly quake has shaken Wellington to the core, as people look at buildings and wonder if they too will crash to the ground. As worry mounts, the city council is reviewing its policy on earthquake-prone buildings, but are we moving fast enough? Dave Burgess reports.

There are an estimated 600 earthquake-prone buildings in Wellington that could kill and maim thousands when the big one strikes.

A list of the earthquake-prone buildings in Wellington

A recent report by Greater Wellington regional council spelt out a bleak picture for the capital of the likely consequences of an earthquake similar to the 7.1 magnitude one in Canterbury last September.

It found up to 1500 people would die and 13,000 would suffer injuries. Previous forecasting estimated 300 deaths in Wellington.

Up to 1500 central city buildings would burn as ruptured gas mains caused fires. About 18,000 homes would be destroyed and 50,000 damaged. Wellington's CBD alone could be strewn with 2.25 million tonnes of debris.

Two years ago, Wellington City Council stretched out by five years the time that owners had to re- strengthen their earthquake-prone buildings. But after Canterbury's 7.1 magnitude shake in September, the capital's earthquake-prone policy was reviewed, with the findings due this month. This study has since been extended to consider lessons from last month's killer quake.


The review will not only consider reducing the time owners have to strengthen their buildings, but also whether appropriate heritage rules could be relaxed to allow more latitude and flexibility in strengthening.

It could lead to the replacement of heavy masonry such as parapets or chimneys with replicas built from lighter glass-fibre, timber or carbon-fibre materials.

Rule changes could force building owners who can't afford the strengthening work to remove these heavy and dangerous parapets and chimneys from the roofs and facades of their premises.

There may also be an increase in grant funding to help more owners complete strengthening work.

Wellington Mayor Celia Wade- Brown says the restrengthening timeframes - 10, 15 or 20 years depending on the work required - are maximums. They were imposed, partly, to give building owners time to find money to pay for the work.

"There is nothing to stop a building owner from strengthening their building more quickly or to a higher standard than required by legislation. We would actively encourage it," she says.

"In fact, there is nothing to stop a building owner from assessing and undertaking strengthening work before their building is even assessed by the council."

Some building owners, such as Victoria University, have already taken this approach.

If the review says that all buildings must be strengthened within a short time - say five years - it then throws up the question of who should pay.

But Ms Wade-Brown says the major financial burden should be on building owners. "[They] should take . . . the majority of the cost. After all, if they strengthen then they are able to secure or increase the value of their property and demand higher rentals.

"It is also likely that the insurers will take a dim view of the buildings that are not strengthened."

However, the city council has a history of financially supporting the strengthening of some buildings, especially ones on its heritage list, she says.

Wellington Central MP Grant Robertson says a lot of buildings need work but the recession means money is tight and many building owners would struggle to meet the cost of restrengthening.

"One possibility is there could be some central-local government partnership to do this . . . I will approach the Government about this at an opportune moment after things have settled down in Christchurch."

Ms Wade-Brown dismissed criticism that her council has allowed so many earthquake-prone buildings into the city. "The initial approach in the 1970s was to encourage the wholesale demolition of fragile and dangerous Victorian and Edwardian buildings. That continued into the 1980s.

"Since then, the council has acknowledged the importance of our heritage [and] scores of buildings have been strengthened in the past 20 years. The city is vastly safer than it used to be, and that's because we've always had a much tougher approach to quake- strengthening than anywhere else in the country."

Deputy Mayor Ian McKinnon, speaking as a councillor for the inner-city, says iconic heritage buildings - such as the National War Memorial and the Carillon - should be identified and strengthened. But not all historic buildings should be saved "because the funding won't always be there to ensure its reliability and safety in the case of an earthquake".

"If such buildings have heritage listings but the state, council, and/or the property owner can't afford to maintain them to a standard that will minimise the risk to people in the case of an earthquake, then any proposed heritage listing should be carefully assessed - very simply, life is more important."

Ms Wade-Brown says lessons should also be learned from other quake-prone countries. "I'm keen on the Japanese model, where information is displayed in the entrances to buildings that outlines to occupants and visitors the building's strength and status according to local building codes."

Ohariu's MP, UnitedFuture leader Peter Dunne, has criticised the council for dragging its heels by not providing "proactive and up-to-date information" online about earthquake-prone buildings.

"The council is not just here to take our rates and collect the rubbish. It is not a big ask for them to regularly update their list and put it online."

Ms Wade-Brown pledged to do just that for buildings that have been assessed as earthquake- prone and owners who have been issued a Section 124 notification. That number currently sits at 161.

"We will post the list of Section 124 buildings on our website and keep it accurate and up-to-date."

The council has earmarked central Wellington as a population growth area over the next couple of decades.

Ms Wade-Brown said the fallout from Christchurch's earthquake hasn't changed that view.

"The challenge for the council, and Wellingtonians, is the debate - and ultimate action - over how we deal with our more fragile buildings and whether, for example, the streetscape of Cuba St and Courtenay Place should be retained at all costs."

But the strength of modern Wellington apartments is to a high standard, with all new buildings required to meet current seismic loading standards. In addition, where a building has a change of use - such as conversion to apartments - it is required under the Building Act to be strengthened as near as practicable to 100 per cent of the current new building code, Ms Wade-Brown says.

The Dominion Post