Kit Miyamoto: Death, damage and downtime

AS Christchurch has found, demolition is costly and disruptive. It should be a last resort.

AS Christchurch has found, demolition is costly and disruptive. It should be a last resort.

OPINION: A new report by structural engineer Kit Miyamoto and Deloitte has put a dollar figure on how much a Kaikoura-like quake under Wellington would cost the region and the country in lost economic activity.

At $29 billion, that figure is big.

Consider also the costs of repairing the city, which would almost certainly be far greater than the rebuild bill for Christchurch, and it's fair to assume that rebuilding the capital would be doubtful.

First, let's be clear that protecting lives in an earthquake is, and always should be, the No 1 priority. That's why we have the New Building Standard. For instance, a building that fails to meet 34 per cent of the current NBS is considered earthquake-prone and "likely to collapse causing injury or death, or damage to any other property, during or following a moderate earthquake".

If a building is 100 per cent of the NBS, it is considered that the risk of a building collapsing in a moderate quake, resulting in death, is low.

But as is so often the case when a standard is applied in a real-world situation, the NBS has limitations. Not all buildings are the same and, as we're already seeing in Wellington, sometimes even structural engineering experts can't agree on things in seismic assessments.

The aim of the NBS is to ensure buildings don't collapse and kill people. But what it doesn't do is give us an understanding of how long that building may take to repair, or if it could be repaired at all.  

That means it is possible to have an entire city completely at 100 per cent of code, but much of it unusable after a major earthquake.

Wellingtonians experienced a huge disruption after the Kaikoura quake. That disruption is lingering even now, some six months on. Imagine then, the type of disruption caused if a quake of similar or larger magnitude hit right beneath us.

Wellington is not only New Zealand's second biggest city but also the seat of government and decision-making. It's vital for the entire country that Wellington gets back on its feet as quickly as possible after a quake.

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The cost so far of repairing Christchurch is more than $20 billion, and counting. Even now, the city is far from being back to business as usual. The repair bill for Wellington in a similar scenario would be off the charts. In insurance parlance, the entire city could be a write-off.

The Government appears to recognise the urgency, with consideration of new spending in the upcoming Budget to help Wellington and the lower North Island build "resilience". That is a good thing, though we're yet to see the detail of what this involves.

In the meantime, central government shouldn't be left to do the heavy lifting in Wellington. Nor can local agencies and authorities work on the solutions in isolation. The only way Wellington can really build resilience is to get on quickly with what needs to be done now, driven not only by government but also by the private sector.

Acknowledging that Wellington had a number of weaknesses that had been known about for "many, many years", Finance Minister Steven Joyce said it was time to put "some effort into shorter-term fixes" while dealing with the longer-term issues.

Drawing on our international experience, that's absolutely the correct approach. In my home state of California – one of the most seismically active regions in the world and where I am a commissioner with the California Seismic Safety Commission – we have drawn on past experiences to find better solutions.

The onus is on protecting lives, limiting damage and speeding recovery.

But even after the Canterbury quakes, New Zealand's focus seems still to be on achieving the first outcome. The second and third outcomes rarely rate a mention.

The NBS code does not tell us the likely damage to a building and the cost of repair, or the business interruption caused by the downtime of a damaged building in the event of a major earthquake.

Doing things to limit damage and protect lives is crucial, but so too is ensuring infrastructure such as buildings can be fixed as quickly and cost effectively as possible.

So where should we start? Making Wellington resilient is everyone's responsibility. Government sets the minimum standards, councils facilitate the legislative process, building owners do the work and tenants need to determine the standards they require and if the minimum legislated standard is acceptable.

It must be remembered that the legislative standard is only to prevent death – not damage or downtime.

As tenants and users of the region's buildings, Wellingtonians should decide if they want buildings that can withstand an earthquake and can be quickly and cost-effectively made functional afterwards.

Building owners can and should take the lead, rather than waiting to see what public funding becomes available or what new requirement or deadline is imposed. But this can only be done if Wellington residents demand resilience and are prepared to pay it.

Buildings can never be absolutely quake-proofed. But there are new and proven high-performance engineering solutions available that can be implemented quickly and comparatively more cost effectively. These will protect people and property and reduce the length of time it takes to repair an earthquake damaged building.

Demolishing buildings should be the last resort. In Christchurch, demolition was more often than not the first consideration and we've seen just how disruptive and costly that is. That "knock-it-down" mentality has done more damage than the quakes themselves.

Wellington has the opportunity to act now and avoid the problems Christchurch is still wrestling with.

After all, an ounce of prevention is worth a pound of cure – and costs much, much less.

Kit Miyamoto is chief executive and president of global earthquake structural engineering company Miyamoto International.

 - The Dominion Post


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