But what spared this metropolitan area of 21 million was, at least in part, luck.
The 1985 earthquake was 30 times more powerful than the one on Tuesday. It toppled apartment and office towers, killing more than 10,000 people.
Tuesday’s earthquake, while centered closer to the capital, struck hardest at smaller, less populated buildings, taking fewer lives.
“They were different seismic activities, in magnitude but especially given the distance,” said Dr. Eduardo Reinoso, a researcher specializing in seismic engineering at the National Autonomous University of Mexico. “Because this one was much closer, the shock waves were different. This quake affected shorter houses and buildings, while in 1985 the collapses were mostly high-rises because of the different waves.”
In a 2016 study of a random sample of 150 buildings constructed after 2004, when the new codes were adopted, Mr. Reinoso found that many failed to meet city standards. In many cases, the buildings reviewed did not even have enough necessary paperwork to conduct a full assessment.
As it often goes in Mexico, it is not the law that is problematic, but rather the implementation. Whether because of a lack of political will, the corruption that seethes through the system or the dysfunction of the bureaucracy, one of the deadliest threats that the nation faces has been left unfixed. Once the dust settles, officials will be confronted once more with a choice: whether to truly enforce a public safety imperative or continue with reforms that seem to exist mostly on paper.
“Some developers have their preferred inspectors and they usually hire the same person for their buildings, so that inspector is active, familiar, and always has a ton of work,” said Jorge Ortiz, an engineer and architect who is one of several hundred contract inspectors for the city. “And sometimes if you have several projects, they aren’t there as much or are not present at all phases of construction and that’s when…