In the wake of the Napier earthquake in 1931, a committee was formed that suggested new earthquake-proofing rules that eventually became the 1935 Building Code, which was implemented soon after the First Labour Government came to power.
The Wairapapa quake in 1942 caused damage in Wellington that took a long time to be fixed (due, in no small part, to the war). As a result, the First Labour Government created the Earthquake and War Damage Commission in 1945, as a form of (near) universal, affordable home insurance against force majuere events.
The threat of air raids, gas attacks, invasion, and earthquakes pushed the evolution of civil defence in the inter-war years with Civil Defence finally being founded as part of the country’s reaction to World War 2.
From disasters, we take lessons for the future. What lessons can we learn from the Christchurch earthquake?
I’ve suggested a couple already: making EQC cover truly universal by collecting it along with rates, rather than via insurance, and universal disaster income insurance through a tiny income levy about 1% the size of ACC levies.
It’s becoming clear that building rules will need to be looked at again too. Liquefaction was a major cause of damage in Christchurch (as it was in Napier). As you know by now if you didn’t know before, liquefaction occurs when loose, water-logged soil is shaken violently. The soil is compressed and the water is forced to the surface resulting in a lower ground level and layer of watery mud on top.
The Christchurch Council says that it went to court to try to block some of the worst-hit developments because it was concerned about the danger of liquefaction in a major quake but it was unable to successfully block them. That tells me the rules need strengthening.
We should look to the Netherlands for lessons. They don’t have the earthquake risk we do but virtually their whole country is sandy soil with a very high water table. If anyone knows about stable construction in these conditions, it’s the Dutch. What are their building standards to protect buildings against the risks of sudden settling? I understand that they compress the earth with vibrating machines then drive deep foundations.
Seems like that works against liquefaction too because a few New Zealand bridges and buildings have been built using those practices (ironically, maybe, the Christchurch Council has a very good map of areas exposed to liquefaction and how it can be countered – can’t find the link).
Maybe we need to strengthen the rules to make that kind of liquefaction-proofing a requirement.