Map of life expectancy at birth from Global Education Project.

Thursday, September 21, 2017

Oh, oh, Mexico

Unlike James Taylor, I have really been so I do really know.

As with most natural disasters, the disaster part of earthquakes is only partly natural. Apart from tsunamis, earthquakes per se aren't even very dangerous. If you were standing in an open field and experienced the most intense earthquake in history you'd just feel the ground shaking, be weirded out for thirty seconds, and then get on with your business. (Perhaps you would stop to make a sacrifice to the gods.) There's always the chance of a landslide or flooding from a displaced body of water but these are pretty rare.

What kills and injures people in earthquakes, for the most part, is architecture. In California, building codes have gotten more and more stringent over the years as tragic experience has pierced through denial. As the building stock has been replaced and upgraded, the death toll from earthquakes has gone down.

Of course making buildings and viaducts earthquake proof is more expensive, and more expensive is a harder sell in a poorer place. Mexico uses a lot of masonry construction, and a lot of the most dangerous kind, which is unframed masonry. The New York Times has a video of the scene at the collapsed Enrique Rebs├ímen elementary school and sure enough, you can see that it was an unframed masonry building. It consisted of concrete slabs resting on concrete pillars. There is no sign of any steel framing. This is a heart rending tragedy -- at least 40 children are known dead and there be many more.

But you will notice that the other buildings around it did not collapse. Whether the current operators of the school understood the construction or the danger I have no idea. But somebody built it, presumably as a school, and the authorities allowed it to be built and occupied. So no, this is not a natural disaster. We know that earthquakes will occur there, they do so regularly. But the consequences can be mitigated, if there is political will, and no corruption. I don't know how old the building was, whether it was non-compliant with codes when it was built, or anything more about this story than what I could see in the video. But I hope people in Mexico and beyond will learn from this.

BTW there have been similar tragedies in China where school buildings in earthquake prone areas were shoddily constructed. I hope the Chinese are taking this seriously as well.

Update: According to NPR, three quarters of the school, which was built some 40 years ago, remained intact. The part that collapsed was ten years old, built after the last earthquake. Mexico City has stringent building standards, but the problem is enforcement. Evidently the death of all those children was indeed a crime. Let's hope the perpetrators are brought to justice.

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