What have we learned from the Kaikoura Earthquake, 8 months on? Surely, seven years on from the Canterbury quakes, we are saturated with knowledge, experience, and the very latest research, that puts us at the leading edge of helping protect our communities from the impacts of earthquakes. Well yes, and no.
Our technical knowledge has expanded significantly, with design theory proved or disproved, a flood of new materials and techniques, a significant influx of highly skilled and well trained people, and our building industry ready to adopt and even highlight the latest materials and structural systems. That seismic bracing we used to try to hide behind Gib walls is now proudly on display inside and outside new and older buildings (enhanced with pot plants where needed to avoid hitting our heads).
But was our readiness for the Kaikoura earthquakes all it could have been? Just a few observations on human factors:
Confidence. Christchurch was rocked a little, but for longer than we were used to. There was clearly confidence in our building stock six years on, with almost no interruption to occupancy. Even though there may have been some surprise at cracks in new Gib linings, most people are now aware that their structures have been thoroughly assessed and strengthened, so were not too alarmed. To the north, just 20km from the epicentre, the 1935 Hanmer Springs Heritage Hotel (an early reinforced concrete structure) continued to operate. Contrast this with Wellington, where buildings have been evacuated or have concerns following rapid assessments, yet we have had six years of heightened seismic awareness to investigate these risks. Our new Earthquake Prone Buildings legislation (effective 1 July) will help address confidence in our older building stock, but still leaves those newer buildings (>34%NBS) which their owners and occupants could decide to have assessed sooner or more extensively.
Perseverance. Further up the coast the earthquake was much more severe, but the storey was one of quite robust rural buildings, some tough people used to dealing with the rigours of the environment, and efforts more focussed on infrastructure. The scale of effort going in to road and rail repairs is enormous, and will likely result in business as usual about a year later. It has also introduced an new era of smiling, friendly stop/go professionals operating in tough conditions. Perfect to counter the frustrations of the journey – well done!
Plan B. We have always known that Kaikoura is in a high seismic risk area. A major concern is a warning to us about our reliance on a single north/south transport route. As Aucklanders understand with their power supply disruption some time ago, having a plan B in place is a simple and effective way to mitigate risk. Our inland route has needed some rapid upgrades, is much longer and prone to disruptions, but we have dodged a bullet by having that option. We tend to think of risk as a bad thing – but it is only bad if we choose not to deal with it. Maybe it’s time though to think about other areas of concentrated risk in our country, and deal with it sooner rather than later. What about:
- Industry concentrations, such as our wine industry concentrated in Marlborough (high seismic risk area).
- Our government and public sector concentrated in Wellington (high seismic risk area).
- Our largest commercial centre based around the Auckland isthmus (volcanoes).
We shouldn’t be obsessed by earthquake risk, but we are still overdue for the Alpine Fault rupture. Let’s just think about it. We have some talented people and great tools to deal with it.