Colombia's Deadliest Earthquake in a Decade: What Happened on 10 August

In Manizales, in the mountainous coffee region, one of the towers of the neo-Gothic cathedral collapsed into the nave, and the city's cable car system was suspended after structural damage. Manizales sits on steep terrain, which introduces landslide risk on top of shaking.

The response, and one notable decision

Colombia declared a national disaster. Rescue operations were activated, and economic emergency measures announced.

International offers of help came from Ecuador, Venezuela, the United States, which pledged 15.5 million dollars, Israel and others. Colombia reportedly declined foreign search and rescue teams while accepting financial support.

That decision will be debated, and it is less unusual than it sounds. Foreign urban search and rescue teams take 24 to 72 hours to arrive and require substantial local coordination, by which point the survival window in collapsed structures has largely closed. Countries with capable domestic capacity often conclude that money and materials help more than more people on the ground. Whether that judgement was right here will depend on what the recovery in Choco looked like, and reporting from the epicentral area was slow because the roads were cut.

Why western Colombia

Colombia sits at one of the more complicated tectonic junctions on earth, where the Nazca, Caribbean and South American plates interact. The Nazca plate subducts beneath the continent, and most large Colombian earthquakes originate in that process.

This one was unusual in occurring inside the descending slab at intermediate depth, in a zone where the rock is cooler than surrounding mantle and can still fracture rather than deform. Colombia has had events like it before, including the intermediate-depth earthquakes felt strongly in Bogota in 2023.

What this tells the rest of the world

Three things, and none of them are about Colombia specifically.

First, building performance decides the toll. A magnitude 7.4 at 110 km depth is survivable almost everywhere with modern construction and lethal wherever construction is old, unreinforced or informal. The earthquake did not choose the 48 buildings that collapsed. Their construction did.

Second, critical facilities need to be built to a higher standard than housing. A hospital that fails in an earthquake fails twice.

Third, this happened without warning of any kind, because that is the only way earthquakes happen. Claims circulating afterwards that someone predicted it deserve the scrutiny we give them in why earthquakes cannot be predicted.

What can be done is preparation, and the practical version of that, drawing on guidance from the Gulf, the United States and Europe, is in our safety guide.