John Roughan: Faultline runs through risk evaluation

It will be hard to stop the loss of character buildings countrywide if proposed earthquake regulations become law. Photo / APN

Our character buildings may pay unnecessary post-quake price

Every time I drive down the hill to my place I bless a little brick steepled church that is our only building of distinction. It gives the bay the character of a bucolic village, almost as though it was nestled in the real East Coast, not Auckland's.

Somehow in recent decades the church survived amalgamation with a larger parish and the rising value of its real estate. Now I fear it may fall victim to Christchurch's earthquake.

The repercussions of that calamity, two years ago this month, are coming to all corners of the country, transmitted not by geological faults but a human failing: the inability to evaluate risk.

Building Minister Maurice Williamson held a public meeting in Auckland this week to invite views on a proposal from the royal commission of inquiry into the Canterbury quakes and a review of the building code by his ministry. Both recommend amending the Building Act to give owners of unreinforced masonry buildings a deadline to bring them up to a moderate earthquake standard or demolish them.

Exceptions might be made for the odd historic building but not, I imagine, for most of those that lend their character to the likes of Herne Bay, Devonport or Mt Eden, or many of the stately buildings that survive in small towns.

City and district councils would have to make a list of "earthquake-prone" buildings within five years and their owners would have 10 years to upgrade or demolish.

The plan doesn't apply to private houses, which will be a relief to those of us living in brick or unfilled block, and that says something about our view of risk. Privately and individually we have a healthier attitude to it than we express in public and political debate.

If you want to say I'm irresponsible for having a house of unreinforced masonry it's hard to answer the charge. But weighing the likelihood of Auckland receiving a seismic shock against the cost of rebuilding the house, I feel pretty relaxed.

The royal commission thinks city councils are irresponsible for having a "passive approach" to earthquake-prone buildings - requiring them to be strengthened only if and when the owner seeks consent for alterations.

That seems a sensible approach, certainly for Auckland where we're told we're in more danger of a new volcano than an earthquake of destructive magnitude. (Volcanoes have formed in the Auckland field about every 10,000 years and Rangitoto erupted less than 1000 years ago, so we have some time.)

Of course it could happen tomorrow, anything could. Considering the risk of meeting a drunken driver head-on around the next corner, we should never get in a car. The ministry's paper says our risk of dying in a motor accident is one in 10,000. The risk of being killed in an earthquake? One in a million.

That's not to say the country should not take precautions, which it has. Buildings erected since 1976 have had to be designed to withstand a quake of a magnitude likely to occur in their region once in 500 years.

Older buildings are supposed to be strengthened to a third of that standard but councils in seismically quiet regions have been relaxed about it - so relaxed that some have no tally of the buildings likely to be bowled if local discretion is removed and all must meet a deadline of 15 years.

It's worth noting of the 185 who died in Christchurch that terrible day, 133 were in two modern buildings. The remaining toll was remarkably low considering the numbers in the shops that afternoon. It suggests old buildings crumble slowly.

Yet in the wake of Christchurch it is going to be hard to stop their destruction by Government notice. Individually we may take a sensible view of our personal earthquake risk but when it comes to public policy, where we don't face the expense individually, the consensus is likely to be that something should be done.

The "something" need go no further than improving public information. Councils could be required to identify all public and commercial buildings that don't measure up to the stipulated one third of the standard for new construction, and publish the list.

The shops and other buildings defined as earthquake-prone should have to post a notice at their entrance that they wouldn't be safe in a moderate or serious earthquake.

It would be interesting to see how many people would enter them. My guess is nearly everyone. The royal commission calls that risk "optimistic bias". I call it common sense.