Since the Sylmar earthquake struck in 1971, Los Angeles officials have been aware of the dangers posed by concrete buildings. Though seismic codes were changed in the aftermath of that quake, owners of buildings built before 1971 have never been required to reinforce their structures. Furthermore, efforts to simply identify which buildings are at risk and label the hazardous ones have been blocked repeatedly.
According to Rong-Gong Lin II, Rosanna Xia and Doug Smith, researchers and reporters have catalogued more than a thousand older concrete buildings across Los Angeles County that could be at risk of collapse in a major earthquake. But without official action, it's up to building owners to investigate and invest in any seismic improvements—a cost many are unwilling to bear voluntarily.
"We know darn well that if a bunch of people die, there will be lots of stories, lots of reports, things will change," said Thomas Heaton, director of Caltech's Earthquake Engineering Research Laboratory. "But the question is, do we have to have lots of people die in order to make this change?"